Yasuhiko Iwamoto

Diabetes mellitus is a group of diseases associated with various metabolic disorders, the main feature of which is chronic hyperglycemia due to insufficient insulin action. Its pathogenesis involves both genetic and environmental factors. The long-term persistence of metabolic disorders can cause susceptibility to specific complications and also foster arteriosclerosis. Diabetes mellitus is associated with a broad range of clinical presentations, from being asymptomatic to ketoacidosis or coma, depending on the degree of metabolic disorder. CLASSIFICATION TABLES 1 AND 2 AND FIGURE 1: [Table: see text] [Table: see text] Figure 1 A scheme of the relationship between etiology (mechanism) and patho-physiological stages (states) of diabetes mellitus. Arrows pointing right represent worsening of glucose metabolism disorders (including onset of diabetes mellitus). Among the arrow lines, indicates the condition classified as 'diabetes mellitus'. Arrows pointing left represent improvement in the glucose metabolism disorder. The broken lines indicate events of low frequency. For example, in type 2 diabetes mellitus, infection can lead to ketoacidosis and require temporary insulin treatment for survival. Also, once diabetes mellitus has developed, it is treated as diabetes mellitus regardless of improvement in glucose metabolism, therefore, the arrow lines pointing left are filled in black. In such cases, a broken line is used, because complete normalization of glucose metabolism is rare.imageThe classification of glucose metabolism disorders is principally derived from etiology, and includes staging of pathophysiology based on the degree of deficiency of insulin action. These disorders are classified into four groups: (i) type 1 diabetes mellitus; (ii) type 2 diabetes mellitus; (iii) diabetes mellitus due to other specific mechanisms or diseases; and (iv) gestational diabetes mellitus. Type 1 diabetes is characterized by destruction of pancreatic β-cells. Type 2 diabetes is characterized by combinations of decreased insulin secretion and decreased insulin sensitivity (insulin resistance). Glucose metabolism disorders in category (iii) are divided into two subgroups; subgroup A is diabetes in which a genetic abnormality has been identified, and subgroup B is diabetes associated with other pathologic disorders or clinical conditions. The staging of glucose metabolism includes normal, borderline and diabetic stages depending on the degree of hyperglycemia occurring as a result of the lack of insulin action or clinical condition. The diabetic stage is then subdivided into three substages: non-insulin- requiring, insulin-requiring for glycemic control, and insulin-dependent for survival. The two former conditions are called non-insulin-dependent diabetes and the latter is known as insulin-dependent diabetes. In each individual, these stages may vary according to the deterioration or the improvement of the metabolic state, either spontaneously or by treatment. DIAGNOSIS TABLES 3–7 AND FIGURE 2: [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] Figure 2 Flow chart outlining steps in the clinical diagnosis of diabetes mellitus. *The value for HbA1c (%) is indicated with 0.4% added to HbA1c (JDS) (%).imageCategories of the State of Glycemia: Confirmation of chronic hyperglycemia is essential for the diagnosis of diabetes mellitus. When plasma glucose levels are used to determine the categories of glycemia, patients are classified as having a diabetic type if they meet one of the following criteria: (i) fasting plasma glucose level of ≥126 mg/dL (≥7.0 mmol/L); (ii) 2-h value of ≥200 mg/dL (≥11.1 mmol/L) in 75 g oral glucose tolerance test (OGTT); or (iii) casual plasma glucose level of ≥200 mg/dL (≥11.1 mmol/L). Normal type is defined as fasting plasma glucose level of <110 mg/dL (<6.1 mmol/L) and 2-h value of <140 mg/dL (<7.8 mmol/L) in OGTT. Borderline type (neither diabetic nor normal type) is defined as falling between the diabetic and normal values. According to the current revision, in addition to the earlier listed plasma glucose values, hemoglobin A1c (HbA1c) has been given a more prominent position as one of the diagnostic criteria. That is, (iv) HbA1c≥6.5% is now also considered to indicate diabetic type. The value of HbA1c, which is equivalent to the internationally used HbA1c (%) (HbA1c [NGSP]) defined by the NGSP (National Glycohemoglobin Standardization Program), is expressed by adding 0.4% to the HbA1c (JDS) (%) defined by the Japan Diabetes Society (JDS). Subjects with borderline type have a high rate of developing diabetes mellitus, and correspond to the combination of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) noted by the American Diabetes Association (ADA) and WHO. Although borderline cases show few of the specific complications of diabetes mellitus, the risk of arteriosclerosis is higher than those of normal type. When HbA1c is 6.0-6.4%, suspected diabetes mellitus cannot be excluded, and when HbA1c of 5.6-5.9% is included, it forms a group with a high risk for developing diabetes mellitus in the future, even if they do not have it currently. Clinical Diagnosis: 1 If any of the criteria for diabetic type (i) through to (iv) is observed at the initial examination, the patient is judged to be 'diabetic type'. Re-examination is conducted on another day, and if 'diabetic type' is reconfirmed, diabetes mellitus is diagnosed. However, a diagnosis cannot be made only by the re-examination of HbA1c alone. Moreover, if the plasma glucose values (any of criteria [i], [ii], or [iii]) and the HbA1c (criterion [iv]) in the same blood sample both indicate diabetic type, diabetes mellitus is diagnosed based on the initial examination alone. If HbA1c is used, it is essential that the plasma glucose level (criteria [i], [ii] or [iii]) also indicates diabetic type for a diagnosis of diabetes mellitus. When diabetes mellitus is suspected, HbA1c should be measured at the same time as examination for plasma glucose.2 If the plasma glucose level indicates diabetic type (any of [i], [ii], or [iii]) and either of the following conditions exists, diabetes mellitus can be diagnosed immediately at the initial examination.• The presence of typical symptoms of diabetes mellitus (thirst, polydipsia, polyuria, weight loss)• The presence of definite diabetic retinopathy3 If it can be confirmed that the above conditions 1 or 2 existed in the past, diabetes mellitus can be diagnosed or suspected regardless of the current test results.4 If the diagnosis of diabetes cannot be established by these procedures, the patient is followed up and re-examined after an appropriate interval.5 The physician should assess not only the presence or absence of diabetes, but also its etiology and glycemic stage, and the presence and absence of diabetic complications or associated conditions. Epidemiological Study: For the purpose of estimating the frequency of diabetes mellitus, 'diabetes mellitus' can be substituted for the determination of 'diabetic type' from a single examination. In this case, HbA1c≥6.5% alone can be defined as 'diabetes mellitus'. Health Screening: It is important not to misdiagnose diabetes mellitus, and thus clinical information such as family history and obesity should be referred to at the time of screening in addition to an index for plasma glucose level. Gestational Diabetes Mellitus: There are two hyperglycemic disorders in pregnancy: (i) gestational diabetes mellitus (GDM); and (ii) diabetes mellitus. GDM is diagnosed if one or more of the following criteria is met in a 75 g OGTT during pregnancy: 1 Fasting plasma glucose level of ≥92 mg/dL (5.1 mmol/L)2 1-h value of ≥180 mg/dL (10.0 mmol/L)3 2-h value of ≥153 mg/dL (8.5 mmol/L) However, diabetes mellitus that is diagnosed by the clinical diagnosis of diabetes mellitus defined earlier is excluded from GDM. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00074.x, 2010).

In 1995, the Japan Diabetes Society (JDS) appointed the Committee for the Classification and Diagnosis of Diabetes Mellitus. The Committee presented a final report in May 1999 in Japanese. This is the English version with minor modifications for readers outside Japan.Concept of diabetes mellitus: Diabetes mellitus represents a group of diseases of heterogeneous etiology, characterized by chronic hyperglycemia and other metabolic abnormalities, which are due to deficiency of insulin effect. After a long duration of metabolic derangement, specific complications of diabetes (retinopathy, nephropathy, and neuropathy) may occur. Arteriosclerosis is also accelerated. Depending on the severity of the metabolic abnormality, diabetes may be asymptomatic, or may be associated with symptoms (thirst, polyuria, and weight loss), or may progress to ketoacidosis and coma.Classification (cf. Tables 1 and 2 and Fig. 1): Both etiological classification and staging of pathophysiology by the degree of deficiency of insulin effect need to be considered. The etiological classification of diabetes and related disorders of glycemia includes, (1) type 1; (2) type 2; (3) those due to specific mechanisms and diseases; and (4) gestational diabetes mellitus. Type 1 is characterized by destructive lesions of pancreatic β cells either by an autoimmune mechanism or of unknown cause. Type 2 diabetes is characterized by combinations of decreased insulin secretion and decreased insulin sensitivity (insulin resistance). Category (3) includes two subgroups; subgroup A is diabetes in which specific mutations have been identified as a cause of genetic susceptibility, while subgroup B is diabetes associated with other pathologic conditions or diseases. The staging of glucose metabolism includes normal, borderline and diabetic stages. The diabetic stage is further classified into three substages; non-insulin requiring, insulin-requiring for glycemic control, and insulin-dependent (ID) for survival. In each individual, these stages may vary according to the deterioration or the improvement of the metabolic state, either spontaneously or by treatment.Diagnosis (cf. Tables 3 and 4): The confirmation of chronic hyperglycemia is a prerequisite for the diagnosis of diabetes mellitus. The state of glycemia may be classified within three categories, diabetic type; borderline type; and normal type. Diabetic type is defined when fasting plasma glucose (FPG) is 7.0 mmol/l (126 mg/dl) or higher, and/or plasma glucose 2 h after 75 g glucose load (2hPG) is 11.1 mmol/l (200 mg/dl) or higher. A casual plasma glucose (PG) ≥11.1 mmol/l (200 mg/dl) also indicates diabetic type. Normal type is defined when FPG is below 6.1 mmol/l (110 mg/dl) and 2hPG below 7.8 mmol/l (140 mg/dl). Borderline type includes those who are neither diabetic nor normal types. These cutoff values are for venous PG measurements. The persistence of ‘diabetic type’ in a subject indicates that he or she has diabetes. For children, a dose of 1.75 g/kg (maximum, 75 g) is used for oral glucose tolerance test (OGTT). The procedure for clinical diagnosis is as follows. 1Diabetes mellitus is diagnosed when hyperglycemia meeting the criteria for ‘diabetic type’ is shown on two or more occasions examined on separate days. 2Diabetes can be diagnosed by a single PG test of ‘diabetic type’ if one of the following three conditions co-exists, (1) typical symptoms of diabetes mellitus; (2) HbA1c ≥6.5% by a standardized method; or (3) unequivocal diabetic retinopathy. 3If the above conditions ((1) or (2)) have been present in the past and well documented, the subject is diagnosed either to have diabetes or to be suspected of diabetes, even if the present level of glycemia does not reach that of ‘diabetic type’. 4If the diagnosis of diabetes cannot be established by these procedures, re-testing of PG is recommended after an appropriate interval. 5The physician should assess not only the presence or absence of diabetes, but also its etiology and glycemic stage, and the presence and absence of diabetic complications or associated conditions. Epidemiological aspects and screening: In order to determine the prevalence of diabetes in a population, ‘diabetic type’ may be regarded as ‘diabetes’. The use of 2hPG cutoff level of ≥11.1 mmol/l (200 mg/dl) is recommended. If this is difficult, the FPG cutoff level of ≥7.0 mmol/l (126 mg/dl) can be used, but is likely to lead to under-ascertainment. For screening, the most important point is not to overlook ‘diabetes’. In addition to parameters of hyperglycemia, clinical information such as family history, obesity etc., should be regarded as indications for further testing.Normal type and borderline type: Only FPG and 2hPG are adopted as cutoff values, but in clinical situations, it is recommended to measure PG also at 30 and 60 min during 75 g OGTT. Among people with normal type, those with 1hPG higher than 10.0 mmol/l (180 mg/dl) are at higher risk to develop diabetes than those with lower 1hPG. When OGTT is performed, the borderline type corresponds to the sum of impaired fasting glycemia (IFG) plus impaired glucose tolerance (IGT) according to the new WHO report. Subjects in this category are at higher risk of developing diabetes than those with ‘normal type’. Those with low insulinogenic index (the ratio of increment of plasma insulin to that of PG at 30 min during OGTT) are at particularly high risk to develop diabetes. Microvascular complications are rare but arteriosclerotic complications are fairly frequent in this category.Gestational diabetes mellitus (GDM): The current definition of GDM is ‘ any glucose intolerance developed or detected during pregnancy’. We adopt the proposal of the Japan Society of Gynecology and Obstetrics for the diagnosis of GDM (1984). GDM is defined when two or more values during a 75 g OGTT are higher than the following cutoff levels; FPG ≥5.5 mmol/l (100 mg/dl), 1hPG ≥10.0 mmol/l (180 mg/dl) and 2hPG ≥8.3 mmol/l (150 mg/dl). As a screening test, subjects with casual PG ≥5.5 mmol/l (100 mg/dl) are recommended for further testing. Patients who have had documented glucose intolerance before pregnancy, and who present as ‘diabetic type’ should be under closer supervision than those who develop GDM during pregnancy for the first time.HbA1c: There is a large overlap in the distribution of HbA1c between groups with ‘normal type’ and ‘borderline type’ and mild ‘diabetic type’. Therefore, HbA1c is not a suitable parameter to detect mild glucose intolerance. HbA1c higher than 6.5% suggests diabetes, but HbA1c below 6.5% alone should not be taken as evidence against the diagnosis of diabetes.Comparison with reports of American Diabetes Association (ADA) in 1997 and WHO in 1999: The present report is unique in the following points when compared with those of the ADA ‘Diabetes Care 20 (1997) 1183’ and WHO ‘Report of a WHO Consultation (1999)’. (1) Diabetes due to specific mechanisms and diseases is divided into two subgroups; diabetes in which genetic susceptibility is clarified at the DNA level and diabetes associated with other diseases or conditions. (2) Cutoff PG levels are the same as those of ADA and WHO, but a term ‘type’ is added to each glycemic category, because a single coding of ‘diabetic type’ hyperglycemia does not define diabetes. Diabetes is diagnosed when ‘diabetic type’ hyperglycemia is shown on two or more occasions. (3) A single ‘diabetic type’ hyperglycemia is considered sufficient for the diagnosis of diabetes, if the patient has typical symptoms, HbA1c ≥6.5%, or diabetic retinopathy. (4) OGTT is recommended for those with mild hyperglycemia, because FPG criteria alone would overlook many subjects with ‘diabetic type’ in Japan. High 1hPG without elevation of FPG and 2hPG is also considered to be a risk factor for future diabetes. (5) Borderline type in the present report corresponds to the sum of IFG and IGT by WHO when OGTT is performed. (6) New criteria for GDM by OGTT are proposed.

To assess the prevalence of non-alcoholic fatty liver disease (NAFLD) and its association with impaired glucose metabolism in Japanese subjects.One thousand, nine hundred and fifty subjects enrolled in a general health examination programme from September 2002 to February 2003 were recruited. NAFLD was diagnosed if a person showed 'fatty liver' on ultrasonography, and his/her alcohol consumption, estimated by questionnaire, was < 40 gram/week. A general linear model was used for the comparison of estimated means of metabolic variables adjusted for age and body mass index (BMI) between subjects with NAFLD and those without fatty liver. Multivariate regression with fasting plasma glucose (FPG) as the dependent variable was performed in 1547 non-diabetic individuals after adjusting for age, gender, BMI and NAFLD.NAFLD was found in 566 of the 1950 health-check examinees (29%). Its prevalence increased with increasing FPG levels: 27% in the subgroup with normal fasting glucose, 43% in impaired fasting glucose and 62% in newly diagnosed diabetes. Adjusted means of FPG, HbA1c, triglyceride, total protein, albumin, AST and ALT were all significantly higher, while adjusted means of HDL cholesterol and AST/ALT ratio were significantly lower in subjects with NAFLD than those without fatty liver. Multivariate regression analysis showed that NAFLD was independently associated with increasing FPG in non-diabetic individuals.The prevalence of NAFLD was 29% in apparently healthy middle-aged Japanese adults and NAFLD was independently associated with impaired glucose metabolism.

To report the age- and sex-specific prevalence of diabetes and impaired glucose regulation (IGR) according to revised World Health Organization criteria for diabetes in Asian populations.We performed 11 studies of 4 countries, comprising 24,335 subjects (10,851 men and 13,484 women) aged 30-89 years who attended the 2-h oral glucose tolerance test and met the inclusion criteria for data analysis.The prevalence of diabetes increased with age and reached the peak at 70-89 years of age in Chinese and Japanese subjects but peaked at 60-69 years of age followed by a decline at the 70 years of age in Indian subjects. At 30-79 years of age, the 10-year age-specific prevalence of diabetes was higher in Indian than in Chinese and Japanese subjects. Indian subjects also had a higher prevalence of IGR in the younger age-groups (30-49 years) compared with that for Chinese and Japanese subjects. Impaired glucose tolerance was more prevalent than impaired fasting glycemia in all Asian populations studied for all age-groups.Indians had the highest prevalence of diabetes among Asian countries. The age at which the peak prevalence of diabetes was reached was approximately 10 years younger in Indian compared with Chinese and Japanese subjects. Diabetes and IGR will be underestimated in Asians based on the fasting glucose testing alone.

Diabetes mellitus is a group of diseases associated with various metabolic disorders, the main feature of which is chronic hyperglycemia due to insufficient insulin action. Its pathogenesis involves both genetic and environmental factors. The long-term persistence of metabolic disorders can cause susceptibility to specific complications and also foster arteriosclerosis. Diabetes mellitus is associated with a broad range of clinical presentations, from being asymptomatic to ketoacidosis or coma, depending on the degree of metabolic disorder.

Background The increased prevalence of type 2 diabetes mellitus is a major concern for health providers. We therefore assessed whether voglibose, an α-glucosidase inhibitor, could prevent the development of type 2 diabetes in high-risk Japanese individuals with impaired glucose tolerance. Methods 1780 eligible patients on a standard diet and taking regular exercise with impaired glucose tolerance were randomly assigned to oral voglibose 0·2 mg three times a day (n=897) or placebo (n=883) in a multicentre, double-blind, parallel group trial. Treatment was continued until participants developed type 2 diabetes (primary endpoint) or normoglycaemia (secondary endpoint), or for a minimum of 3 years, subject to the findings of an interim analysis. Analysis was by full analysis set. This trial is registered with the University Hospital Medical Information Network (UMIN) clinical trials registry, number UMIN 000001109. Findings In the interim analysis, voglibose was better than placebo (p=0·0026) in individuals treated for an average of 48·1 weeks (SD 36·3). Patients treated with voglibose had a lower risk of progression to type 2 diabetes than did those on placebo (50 of 897 vs 106 of 881; hazard ratio 0·595, 95% CI 0·433–0·818; p=0·0014). More people in the voglibose group achieved normoglycaemia than did those in the placebo group (599 of 897 vs 454 of 881; 1·539, 1·357–1·746; p<0·0001). 810 (90%) of 897 patients in the voglibose group had adverse events versus 750 (85%) of 881 in the placebo group. Serious adverse events (all one each) in the voglibose group were cholecystitis, colonic polyp, rectal neoplasm, inguinal hernia, liver dysfunction, and subarachnoid haemorrhage, and in the placebo group were cerebral infarction and cholecystitis. Interpretation Voglibose, in addition to lifestyle modification, can reduce the development of type 2 diabetes in high-risk Japanese individuals with impaired glucose tolerance. Funding Takeda.

In recent years, several oral antidiabetic drugs with new mechanisms of action have become available, expanding the number of treatment options. Sodium/glucose cotransporter-2 (SGLT2) inhibitors are a new class of oral antidiabetic drugs with an insulin-independent mechanism promoting urinary glucose excretion. We report the results of a combined Phase 2 and 3 clinical study (Japic CTI-101349) of the SGLT2 inhibitor tofogliflozin (CSG452, RG7201) in Japanese patients with type 2 diabetes mellitus.The efficacy and safety of tofogliflozin were assessed in this multicenter, placebo-controlled, randomized, double-blind parallel-group study involving 230 patients with type 2 diabetes mellitus with inadequate glycemic control on diet/exercise therapy. Between 30 October 2010 and 28 February 2012, patients at 33 centers were randomized to either placebo (n = 56) or tofogliflozin (10, 20, or 40 mg; n = 58 each) orally, once daily for 24 weeks. The primary efficacy endpoint was the change from baseline in HbA1c at week 24.Overall, 229 patients were included in the full analysis set (placebo: n = 56; tofogliflozin 10 mg: n = 57; tofogliflozin 20 and 40 mg: n = 58 each). The least squares (LS) mean change (95% confidence interval) from baseline in HbA1c at week 24 was -0.028% (-0.192 to 0.137) in the placebo group, compared with -0.797% (-0.960 to -0.634) in the tofogliflozin 10 mg group, -1.017% (-1.178 to -0.856) in the tofogliflozin 20 mg group, and -0.870% (-1.031 to -0.709) in the tofogliflozin 40 mg group (p < 0.0001 for the LS mean differences in all tofogliflozin groups vs placebo). There were also prominent decreases in fasting blood glucose, 2-h postprandial glucose, and body weight in all tofogliflozin groups compared with the placebo group. The main adverse events were hyperketonemia, ketonuria, and pollakiuria. The incidence of hypoglycemia was low. Furthermore, most adverse events were classified as mild or moderate in severity.Tofogliflozin 10, 20, or 40 mg administered once daily as monotherapy significantly decreased HbA1c and body weight, and was generally well tolerated in Japanese patients with type 2 diabetes mellitus. Phase 3 studies were recently completed and support the findings of this combined Phase 2 and 3 study.This study was registered in the JAPIC clinical trials registry (ID: Japic CTI-101349).

The allele frequencies for a Pro12-->Ala substitution in peroxisome proliferator-activated receptor-gamma differ among ethnic groups, and its relationship with diabetes and associated diseases is controversial. The prevalence of this polymorphism and its effects on clinical characteristics have now been evaluated with a large number of Japanese individuals with type 2 diabetes (n = 2,201) and normal control subjects (n = 1,212) recruited by 10 institutions located in seven different cities in Japan. The allele frequency for the Ala12 variant was significantly lower in the type 2 diabetic group than in the control group (2.39 vs. 4.13%, P = 0.000054). However, compared with subjects without the Ala12 variant, the diabetic subjects with this variant exhibited a significantly higher serum concentration of total cholesterol (P = 0.001), manifested a reduced capacity for insulin secretion as evaluated by homeostasis model assessment (P = 0.007), and tended to possess a higher level of HbA1c. These data suggest that the Ala12 variant is associated with a reduced risk for the development of diabetes in the general population, but that it may be also a risk factor for insulin deficiency and disease severity in individuals with type 2 diabetes.

To date, evidence for long-term renoprotection with angiotensin receptor blockers (ARBs) has come almost exclusively from Caucasian patients (1–3), despite Japanese people being at high risk of diabetic nephropathy and very susceptible to end-stage renal disease (4–6). We conducted the INNOVATION Study (Incipient to Overt: Angiotensin II Blocker, Telmisartan, Investigation on Type 2 Diabetic Nephropathy) to evaluate the efficacy of an ARB in preventing transition from microalbuminuria to overt nephropathy in Japanese patients (7). This study is the first large-scale clinical study to investigate prevention of overt diabetic nephropathy using an ARB in normotensive and hypertensive Japanese patients with type 2 diabetes. The randomized, multicenter, double-blind, placebo-controlled trial was performed in patients aged from 30 to 74 years with type 2 diabetes and urinary albumin-to-creatinine ratio (UACR) 100–300 mg/g and serum creatinine <1.5 mg/dl (men) and <1.3 mg/dl (women). Exclusion criteria included type 1 diabetes, age of diabetes onset <30 years, seated systolic blood pressure (SBP)/diastolic blood pressure (DBP) ≥180/100 mmHg, and definable chronic kidney disease …

To search for a gene(s) conferring susceptibility to diabetic nephropathy (DN), we genotyped over 80,000 gene-based single nucleotide polymorphisms (SNPs) in Japanese patients and identified that the engulfment and cell motility 1 gene (ELMO1) was a likely candidate for conferring susceptibility to DN, in view of the significant association of an SNP in this gene with the disease (intron 18+9170, GG vs. GA+AA, chi(2) = 19.9, P = 0.000008; odds ratio 2.67, 95% CI 1.71-4.16). In situ hybridization (ISH) using the kidney of normal and diabetic mice revealed that ELMO1 expression was weakly detectable mainly in tubular and glomerular epithelial cells in normal mouse kidney and was clearly elevated in the kidney of diabetic mice. Subsequent in vitro analysis revealed that ELMO1 expression was elevated in cells cultured under high glucose conditions (25 mmol/l) compared with cells cultured under normal glucose conditions (5.5 mmol/l). Furthermore, we identified that the expression of extracellular matrix protein genes, such as type 1 collagen and fibronectin, were increased in cells that overexpress ELMO1, whereas the expression of matrix metalloproteinases was decreased. These results indicate that ELMO1 is a novel candidate gene that both confers susceptibility to DN and plays an important role in the development and progression of this disease.

Higher incidence of diabetic nephropathy in type 2 than in type 1 diabetes in early-onset diabetes in Japan.BackgroundWhether the type of diabetes, race, and year and age of diagnosis affect the incidence of diabetic vascular complications is unknown. That both type 1 and type 2 diabetes occur in the young Japanese population prompted us to investigate whether the type of diabetes and the year of diagnosis are related to the incidence of nephropathy.MethodsOf the 17,256 diabetic patients who visited the outpatient clinic at our diabetes center between 1965 and 1990, 1578 (9.1%) had early-onset diabetes (diagnosed before the age of 30); of these, 620 (39%) had type 1, and 958 (61%) had type 2 diabetes. The incidence of nephropathy was analyzed in the patients according to postpubertal duration and year of diagnosis.ResultsThe cumulative incidence of nephropathy after 30 years of postpubertal diabetes was significantly higher (P < 0.0001) in type 2 diabetic patients (44.4%, 95% CI, 37.0 to 51.8%) than in type 1 diabetic patients (20.2%, 95% CI, 14.9 to 25.8%). The incidence of nephropathy among type 1 diabetic patients has declined during the past two decades, whereas it has not among type 2 diabetic patients. The rate ratio for type 2 diabetic patients diagnosed between 1980 and 1984 relative to type 1 diabetic patients diagnosed in the same period was 2.74 (95% CI, 1.17 to 6.41).ConclusionsThe incidence of nephropathy has declined in Japanese patients with type 1 but not in those with type 2 diabetes. In young Japanese patients, because of the higher incidence of nephropathy in type 2 diabetes and the higher prevalence of type 2 than type 1 diabetes, type 2 diabetes is likely the major cause of diabetic nephropathy. Higher incidence of diabetic nephropathy in type 2 than in type 1 diabetes in early-onset diabetes in Japan. Whether the type of diabetes, race, and year and age of diagnosis affect the incidence of diabetic vascular complications is unknown. That both type 1 and type 2 diabetes occur in the young Japanese population prompted us to investigate whether the type of diabetes and the year of diagnosis are related to the incidence of nephropathy. Of the 17,256 diabetic patients who visited the outpatient clinic at our diabetes center between 1965 and 1990, 1578 (9.1%) had early-onset diabetes (diagnosed before the age of 30); of these, 620 (39%) had type 1, and 958 (61%) had type 2 diabetes. The incidence of nephropathy was analyzed in the patients according to postpubertal duration and year of diagnosis. The cumulative incidence of nephropathy after 30 years of postpubertal diabetes was significantly higher (P < 0.0001) in type 2 diabetic patients (44.4%, 95% CI, 37.0 to 51.8%) than in type 1 diabetic patients (20.2%, 95% CI, 14.9 to 25.8%). The incidence of nephropathy among type 1 diabetic patients has declined during the past two decades, whereas it has not among type 2 diabetic patients. The rate ratio for type 2 diabetic patients diagnosed between 1980 and 1984 relative to type 1 diabetic patients diagnosed in the same period was 2.74 (95% CI, 1.17 to 6.41). The incidence of nephropathy has declined in Japanese patients with type 1 but not in those with type 2 diabetes. In young Japanese patients, because of the higher incidence of nephropathy in type 2 diabetes and the higher prevalence of type 2 than type 1 diabetes, type 2 diabetes is likely the major cause of diabetic nephropathy.

Objective To study the effects of CS-045, a newly developed thiazolidine analogue, on glucose tolerance and insulin response to oral glucose load in patients with non-insulin-dependent diabetes mellitus (NIDDM). Research Design and Methods Nineteen NIDDM patients (mean ± SD age 48.9 ± 9.4 yr) whose previous glycemic control on diet and/or sulfonylurea (SU) therapy was judged stable but unsatisfactory (&amp;gt; 7.8 mM) were selected for this study. CS-045 (400 mg/day p.o.) was given alone or together with the previous SU drugs for 12 wk. A 75-g oral glucose tolerance test (OGTT) was performed before and after CS-045 treatment. Results The following results were found after CS-045 treatment. 1) Fasting plasma glucose (FPG) and HbA1c decreased (n = 19, FPG, 11.0 ± 2.4 vs. 8.4 ± 2.7 mM [before vs. after], P &amp;lt; 0.001; HbA1c, 8.0 ± 1.1 vs. 7.4 ± 1.3%, P &amp;lt; 0.005), and glucose tolerance markedly improved. 2) Fasting insulin (immunoreactive insulin [IRI]) and insulin response during OGTT decreased (n = 19, fasting IRI, 77.4 ± 49.8 vs. 56.5 ± 24.6 pM [before vs. after], P &amp;lt; 0.05; area under the curve of IRI, 540.3 ± 350.5 vs. 426.4 ± 216.3 pM.h, P &amp;lt; 0.05). Conclusions CS-045 is effective in improving glucose tolerance without stimulation of insulin secretion in NIDDM, suggesting an effect in improving insulin sensitivity.

The American Diabetes Association recommended that only a single fasting plasma glucose of greater than or equal to 7.0 mmol/l should be used for diagnosing diabetes in epidemiological studies and did not recommend using a 2-h oral glucose tolerance test. We evaluated the effect of diagnostic changes on the prevalence of diabetes and on the choice of subjects diagnosed with diabetes.Existing epidemiological data collected from Asian people between 30 and 89 years of age, was re-analysed separately in 11 population-based studies (n = 17,666), 6 pre-selected hyperglycaemic cohorts (n = 12,221) and one suspected diabetic cohort (n = 8382).Among the 11 population-based studies, the new fasting glucose criteria resulted in an overall reduction of 1.8% in the prevalence of diabetes, which ranged from a reduction of 4.8% to an increase of 1.7% in the different studies. Of 1215 subjects diagnosed with diabetes by either criteria, only 449 met both criteria, a concordance of 37%. More than half of the diabetic subjects had isolated post-challenge hyperglycaemia and three quarters of the subjects with impaired glucose tolerance, according to the 2-h glucose criteria, were normal according to the fasting glucose criteria. Subjects diagnosed as diabetic based only on the 2-h glucose criteria were, on average, older than those with diabetes according to the fasting criteria.The fasting and the 2-h glucose criteria diagnose different groups of subjects. It would therefore be inappropriate to use the fasting glucose criteria alone for screening diabetes in Asian populations.

OBJECTIVE To investigate the clinical efficacy of troglitazone, a newly developed oral hypoglycemic agent, in patients with NIDDM. RESEARCH DESIGN AND METHODS There were 284 NIDDM patients (20–82 years of age) whose glycemic control while on a diet was judged stable but was judged unsatisfactory (fasting plasma glucose [FPG] ≥ 8.3 mmol/l) when entered into a multicenter and double-blind study with parallel groups study. They were randomly allocated into two groups, the troglitazone group (the T group: 400 mg/day p.o.) and the placebo group (the P group), and were treated with test drugs for 12 weeks. RESULTS We evaluated efficacy in 136 patients of the T group and 126 patients of the P group. There was no significant difference in any of baseline characteristics between the T and P groups. In the T group, FPG and HbA1c decreased significantly after treatment (before versus after, FPG 10.1 ± 1.6 vs. 8.8 ± 1.9 mmol/l, P &amp;lt; 0.001; HbA1c: 8.6 ± 1.5 vs 8.1 ± 1.7%, P &amp;lt; 0.001). FPG and HbA1c did not change after treatment in the P group (before versus after, FPG 10.1 ± 1.8 vs. 9.9 ± 2.1 mmol/l; HbA1c 8.5 ± 1.5 vs. 8.6 ± 1.6%). Of 136 patients in the T group, 62 (45.6%) were classified as responders. Serum triglyceride level also decreased in the T group but not in the P group. Body weight increased slightly only in the T group. There were no differences in changes in blood pressure between the two groups. No serious adverse events occurred in either group. CONCLUSIONS Troglitazone at 400 mg/day decreased FPG and HbA1c significantly in NIDDM patients who had failed to respond to diet therapy. Troglitazone, developed as a drug to enhance insulin action, can be a useful hypoglycemic agent for the treatment of NIDDM.

Adriamycin, carminomycin, and daunorubicin inhibit the coenzyme Q10-enzymes, succinoxidase and NADH-oxidase. Adriamycin 14-octanoate, which is more lipoidal than adriamycin, was the most effective inhibitor of the anthracyclines for both enzymes, and was 1/12 as effective as the standard inhibitor, 6-ω-cyclohexylpentyl-5-hydroxy-2,3-dimethoxy-1,4-benzoquinone, of coenzyme Q10 for NADH-oxidase. Lapachol and dichloroallyl lawsone inhibited succinoxidase, and the latter of all quinones was second only to the standard for inhibition. These data indicate that the antitumor activities of adriamycin could possibly be partly due to inhibition of CoQ10-enzymes in electron transfer processes of cell respiration in addition to intercalation within DNA helices.

The transcription factor 7-like 2 gene (TCF7L2) has been shown to be strongly associated with an increased risk of type 2 diabetes in white populations. To further investigate the involvement of TCF7L2 in conferring susceptibility to type 2 diabetes, we examined the association of TCF7L2 polymorphisms with type 2 diabetes in a Japanese population.We analysed four SNPs (rs12255372, rs7903146, rs7901695 and rs11196205) and one tetranucleotide repeat polymorphism (DG10S478) in 1,630 Japanese subjects with type 2 diabetes and 1,064 control subjects.All investigated polymorphisms were significantly associated with type 2 diabetes, and rs12255372 showed the strongest association (T vs G, chi2 = 9.20, p = 0.0024, odds ratio = 1.70, 95% CI = 1.20-2.41), although the frequency of the risk allele in our population was much lower than that in white populations. The microsatellite polymorphism showed an almost complete linkage disequilibrium to rs1255372 when the alleles with longer repeats (+8, +12) were considered as minor alleles and showed an association with type 2 diabetes (chi2 = 5.34, p = 0.021, odds ratio = 1.50, 95% CI = 1.06-2.12).These results indicate that TCF7L2 might be a strong candidate for conferring susceptibility to type 2 diabetes across different ethnicities.

Abstract Background: In Europeans and populations of European origin, several groups have recently identified novel type 2 diabetes susceptibility genes, including FTO, SLC30A8, HHEX, CDKAL1, CDKN2B, and IGF2BP2, none of which were in the list of functional candidates. Objective and Design: The aim of this study was to replicate in a Japanese population previously identified associations of single nucleotide polymorphisms (SNPs) within 10 candidate loci with type 2 diabetes using a relatively large sample size: 1921 subjects with type 2 diabetes and 1622 normal controls. Results: A total of 15 SNPs were genotyped. Eight SNPs in five loci were found to be associated with type 2 diabetes: rs3802177 [odds ratio (OR) = 1.16 (95% confidence interval (CI) 1.05–1.27); P = 4.5 × 10−3] in SLC30A8; rs1111875 [OR = 1.27 (95% CI 1.14–1.40); P = 1.4 × 10−5] and rs7923837 [OR = 1.27 (95% CI 1.13–1.43); P = 1.0 × 10−4] in HHEX; rs10811661 [OR = 1.27 (95% CI 1.15–1.40); P = 1.9 × 10−6] in CDKN2B; rs4402960 [OR = 1.23 (95% CI 1.11–1.36); P = 8.1 × 10−5] and rs1470579 [OR = 1.18 (95% CI 1.07–1.31); P = 8.3 × 10−4] in IGF2BP2; and rs7754840 [OR = 1.28 (95% CI 1.17–1.41); P = 4.5 × 10−7] and rs7756992 [OR = 1.27 (95% CI 1.15–1.40); P = 9.8 × 10−7] in CDKAL1. The first and second strongest associations were found at variants in CDKAL1 and CDKN2B, both of which are involved in the regenerative capacity of pancreatic β-cells. Conclusion: Some of these variants represent common type 2 diabetes-susceptibility genes in both Japanese and Europeans.

Using both human and murine cell lines, we show that malignant cells are able to invade through basement membrane and also secrete elevated amounts of collagenase IV, an enzyme implicated in the degradation of basement membranes. Using serine proteinase inhibitors and antibodies to plasminogen activators as well as a newly described collagenase inhibitor we demonstrate that a protease cascade leads to the activation of an enzyme(s) that cleaves collagen IV. Inhibition at each step reduces the invasion of the tumor cells through reconstituted basement membrane in vitro. Treatment with a collagenase inhibitor reduced the incidence of lung lesions in mice given i.v. injections of malignant melanoma cells.

Insulin degludec (IDeg) is an ultra-long-acting basal insulin with a consistent action profile of >42 h. This trial compared the efficacy and safety of IDeg with insulin glargine (IGlar) in insulin-naïve Asian patients with type 2 diabetes.In this multinational, 26-week, open-label, treat-to-target trial, 435 participants (202 females, 233 males; mean age 58.6 years; mean body mass index 25 kg/m(2); mean glycated hemoglobin [HbA1c] 8.5%) were randomized (2:1) to IDeg or IGlar, each administered once daily with ≥1 oral antidiabetic drug(s) (OAD).After 26 weeks, HbA1c had decreased by 1.24 and 1.35% in the IDeg and IGlar groups, respectively (treatment difference [IDeg - IGlar] 0.11%, 95% confidence interval [CI] -0.03 to 0.24), confirming non-inferiority. Rates of overall confirmed hypoglycemia were similar for IDeg and IGlar during the full trial period (3.0 vs 3.7 episodes/patient-year of exposure [PYE]; rate ratio [RR] 0.82, 95% CI 0.60 to 1.11, P = 0.20), but significantly lower (by 37%) for IDeg during the maintenance period (from week 16 onward; RR 0.63, 95% CI 0.42 to 0.94, P = 0.02). No significant difference in the rate of nocturnal confirmed hypoglycemia was found between IDeg and IGlar in the full trial period (0.8 vs 1.2 episodes/PYE; RR 0.62, 95% CI 0.38 to 1.04, P = 0.07) or maintenance period (RR 0.52, 95% CI 0.27 to 1.00, P = 0.05). Adverse event rates were similar between treatments.Initiating insulin therapy with IDeg in Asian patients with type 2 diabetes, inadequately controlled with OADs, provides similar improvements in long-term glycemic control to IGlar, but at a significantly lower rate of overall confirmed hypoglycemia once stable glycemic control and insulin dosing are achieved. This trial was registered with www.clinicaltrials.gov (no. NCT01059799).

Recent reports have suggested that WNT signaling is an important regulator for adipogenesis or insulin secretion and might be involved in the pathogenesis of type 2 diabetes. To investigate possible roles of the WNT genes in conferring susceptibility to type 2 diabetes, we examined the association of the genes that encode members of the WNT family with type 2 diabetes in the Japanese population. First, 40 single-nucleotide polymorphism (SNP) loci within 11 WNT genes were analyzed in 188 subjects with type 2 diabetes (case-1) and 564 controls (control-1). Among them, six SNP loci exhibited a significant difference (P<.05) in the allele and/or genotype distributions between case and control subjects. These SNP loci were further analyzed in another set of case (case-2; n=733) and control (control-2; n=375) subjects to confirm their statistical significance. As a result, one SNP locus in the WNT5B gene was strongly associated with type 2 diabetes (χ2=15.6; P=.00008; odds ratio=1.74; 95% confidence interval 1.32–2.29). Expression of the WNT5B gene was detectable in several tissues, including adipose, pancreas, and liver. Subsequent in vitro experiments identified the fact that expression of the Wnt5b gene was increased at an early phase of adipocyte differentiation in mouse 3T3-L1 cells. Furthermore, overexpression of the Wnt5b gene in preadipocytes resulted in the promotion of adipogenesis and the enhancement of adipocytokine-gene expression. These results indicate that the WNT5B gene may contribute to conferring susceptibility to type 2 diabetes and may be involved in the pathogenesis of this disease through the regulation of adipocyte function. Recent reports have suggested that WNT signaling is an important regulator for adipogenesis or insulin secretion and might be involved in the pathogenesis of type 2 diabetes. To investigate possible roles of the WNT genes in conferring susceptibility to type 2 diabetes, we examined the association of the genes that encode members of the WNT family with type 2 diabetes in the Japanese population. First, 40 single-nucleotide polymorphism (SNP) loci within 11 WNT genes were analyzed in 188 subjects with type 2 diabetes (case-1) and 564 controls (control-1). Among them, six SNP loci exhibited a significant difference (P<.05) in the allele and/or genotype distributions between case and control subjects. These SNP loci were further analyzed in another set of case (case-2; n=733) and control (control-2; n=375) subjects to confirm their statistical significance. As a result, one SNP locus in the WNT5B gene was strongly associated with type 2 diabetes (χ2=15.6; P=.00008; odds ratio=1.74; 95% confidence interval 1.32–2.29). Expression of the WNT5B gene was detectable in several tissues, including adipose, pancreas, and liver. Subsequent in vitro experiments identified the fact that expression of the Wnt5b gene was increased at an early phase of adipocyte differentiation in mouse 3T3-L1 cells. Furthermore, overexpression of the Wnt5b gene in preadipocytes resulted in the promotion of adipogenesis and the enhancement of adipocytokine-gene expression. These results indicate that the WNT5B gene may contribute to conferring susceptibility to type 2 diabetes and may be involved in the pathogenesis of this disease through the regulation of adipocyte function.

We investigated whether serum levels of N-(carboxymethyl)lysine (CML), non-CML advanced glycation endproducts (AGEs), or pentosidine are associated with severity of diabetic microvascular complications in patients with Type 1 diabetes. Serum levels of CML, non-CML AGE, and pentosidine were measured by an enzyme-linked immunosorbent assay in 38 males and 47 females aged 31+/-8 years (mean+/-S.D.) with Type 1 diabetes for 18.7+/-7.0 years. There was a significant correlation between serum levels of CML or non-CML AGE and current HbA(1c) level (P<.01 and P<.05, respectively). The serum levels of non-CML AGE, but not CML or pentosidine, were significantly increased as normal renal status advanced to microalbuminuria, clinical nephropathy, and hemodialysis (P<.0001) and were positively correlated with urinary albumin excretion (UAE) in patients with Type 1 diabetes (P<.0001). A significant elevation of serum non-CML AGE was found in association with the severity of diabetic retinopathy (P<.0001). We found in the present study that CML levels were also increased in the stage of simple retinopathy, the early stage of clinically evident retinopathy (P<.05). Serum levels of non-CML AGE were significantly associated with the severity of diabetic nephropathy and retinopathy, suggesting a role of non-CML AGE in the progression of microvascular complications in patients with Type 1 diabetes. Since serum levels of CML were significantly increased in patients with simple retinopathy, CML may participate in the initiation of diabetic retinopathy.

The effects of sex hormones on the in vitro chemotaxis of polymorphonuclear leukocytes (PMNs) and monocytes were investigated using fMLP as the chemoattractant. PMNs, monocytes, and plasma were obtained from heparinized peripheral blood of healthy adults. Chemotaxis of PMNs or monocytes treated with sex hormones were tested using 48-well chemotaxis microchambers. The correlation between sex hormone levels in plasma and the chemotactic ability of PMNs from the same donor was also investigated. The chemotaxis of PMNs was enhanced by progesterone, while it was reduced by estradiol. Random migration of PMNs was also enhanced by progesterone and reduced by estradiol. The effect of estradiol on PMN chemotaxis was inhibited by addition of antiestrogens or progesterone. Testosterone did not have a measurable effect on PMN chemotaxis. A significant positive correlation was found between the concentration of progesterone in plasma of females and PMN chemotactic ability in vitro. For males, there was no significant relationship between plasma levels of sex hormones and PMN chemotactic ability. Estradiol and testosterone levels in plasma did not correlate with PMN chemotactic ability. Sex hormones had no effect on the chemotaxis of monocytes. These results suggest that the altered PMN chemotaxis associated with gingival inflammation may be due to the effects of sex hormones.

Although HLA-DQB1 alleles encoding aspartic acid at position 57 (Asp-57) are protective against Type 1 (insulin-dependent) diabetes mellitus in Caucasians, most Japanese Type 1 diabetic patients carry at least one Asp-57 DQB1 allele. We analysed the DRB1, DQA1 and DQB1 genes of 99 Japanese patients and 86 control subjects with polymerase chain reaction and sequence-specific oligonucleotide hybridization. We found that (1) the DQA1*0301 allele was significantly increased in Type 1 diabetic patients (RR7.8, pc less than 0.0001); (2) the DRB1*0405 (Dw15) allele, which is a subtype of DR4 haplotype, was significantly increased in DR4-positive patients (RR 12.0, pc less than 0.001); and (3) although the DRw8-DQw8 haplotype was positively associated with Type 1 diabetes, the DRB1*0406-DQw8 haplotype was decreased in the diabetic patients. These data indicate that DRB1 and DQA1 genes also confer susceptibility to Type 1 diabetes in Japanese.

We measured the health-related quality of life (HRQL) of diabetes mellitus patients using the Japanese version of EQ-5D, and examined the relationship between clinical condition and health status.A study was conducted on 220 patients with type 2 diabetes mellitus at a hospital in Saitama Prefecture on the day of their visit from November 17 to December 24, 1998. Patients evaluated their health status using five dimensions (5D) and a visual analog scale (VAS). The EQ-5D score was calculated based on the 5D responses using the Japanese version of the value set.There were no responses of "extreme problem." The frequency of "some problem" was significantly higher in patients with complications than in those without for mobility (27.4% and 14.4%) and anxiety/depression (25.7% and 13.5%). The mean EQ-5D score was 0.846 (95% confidence interval [CI] 0.817-0.874) in patients with complications versus 0.884 (95% CI 0.855-0.914) in those without complications. There was no statistically significant difference between VAS scores according to the presence or absence of diabetic complications, but a significant difference in VAS scores was seen according to the presence or absence of retinopathy.These findings suggest the value of measuring health status in diabetes mellitus patients, because it is able to comprehensively evaluate the patient's health condition, and add another dimension to the subjective symptoms and laboratory data.

To compare the efficacy and safety of sitagliptin (a dipeptidyl peptidase-4 inhibitor) and voglibose (an alpha-glucosidase inhibitor) monotherapy in Japanese patients with type 2 diabetes who have inadequate glycaemic control (HbA1c > or =6.5% and <10.0%) on diet and exercise.In a multi-center, randomized, double-blind, parallel-group study, 319 patients were randomized (1:1) to 12-week treatment with sitagliptin 50 mg once daily or voglibose 0.2 mg thrice daily before meals. The primary analysis assessed whether sitagliptin was non-inferior to voglibose in lowering HbA1c.After 12 weeks, sitagliptin was non-inferior to voglibose for HbA1c-lowering efficacy. Furthermore, sitagliptin was superior to voglibose, providing significantly greater reductions in HbA1c from baseline [least squares mean changes in HbA1c [95% confidence intervals (CI)] = -0.7% (-0.8 to -0.6) and -0.3% (-0.4 to -0.2), respectively; between-group difference = -0.4% (-0.5 to -0.3), p < 0.001]. Sitagliptin was also superior to voglibose on other key efficacy endpoints, including change from baseline in 2-h postmeal glucose (-2.8 mmol/l vs. -1.8 mmol/l, p < 0.001) and fasting plasma glucose (-1.1 mmol/l vs. -0.5 mmol/l, p < 0.001). After 12 weeks, the incidences of clinical adverse experiences (AEs), drug-related AEs and gastrointestinal AEs in the sitagliptin group (48.5, 10.4 and 18.4%, respectively) were significantly (p < 0.05) lower than those in the voglibose group (64.7, 26.3 and 34.6%, respectively). The incidences of hypoglycaemia, serious AEs and discontinuations due to AEs were low and similar in both groups.In Japanese patients with type 2 diabetes, once-daily sitagliptin monotherapy showed greater efficacy and better tolerability than thrice-daily voglibose over 12 weeks.

Sitagliptin is an oral, potent, highly selective, once-daily DPP-4 inhibitor indicated for the treatment of type 2 diabetes mellitus (T2DM). To assess the dose-ranging efficacy and safety/tolerability profile of once-daily sitagliptin 25, 50, 100, and 200 mg in Japanese patients with T2DM. In this randomized, double-blind, placebo-controlled study, 363 Japanese patients with inadequate glycemic control (HbA(1c)=6.5-10%; FPG< or =270 mg/dL) were randomized (1:1:1:1:1) to placebo, sitagliptin 25, 50, 100, or 200 mg q.d. for 12 weeks. The primary endpoint was change from baseline in HbA(1c) at Week 12. At Week 12, treatment with sitagliptin at all doses tested provided significant (p<0.001) reductions in HbA(1c) (-0.69 to -1.04%) from baseline (7.49 to 7.65%) relative to placebo. Sitagliptin significantly (p<0.001) reduced fasting plasma glucose (FPG; -15.9 to -23.2 mg/dL) and 2-hour postprandial glucose (2-hr PPG; -40.3 to -65.0 mg/dL) relative to placebo, in a dose-dependent manner. At doses > or =50 mg, differences in HbA(1c), FPG, and 2-hr PPG between the sitagliptin groups were not statistically significant. Sitagliptin was generally well tolerated with a low and similar incidence of hypoglycemia and minimal weight gain relative to placebo. Treatment with sitagliptin for 12 weeks provided significant and clinically meaningful reductions in HbA(1c), FPG, and 2-hr PPG across the dose range studied and was generally well tolerated in Japanese patients with T2DM.

It has been suggested that genetic susceptibility plays an important role in the pathogenesis of diabetic nephropathy. A large-scale genotyping analysis of gene-based single nucleotide polymorphisms (SNPs) in Japanese patients with type 2 diabetes identified the gene encoding acetyl-coenzyme A carboxylase beta (ACACB) as a candidate for a susceptibility to diabetic nephropathy; the landmark SNP was found in the intron 18 of ACACB (rs2268388: intron 18 +4139 C > T, p = 1.4x10(-6), odds ratio = 1.61, 95% confidence interval [CI]: 1.33-1.96). The association of this SNP with diabetic nephropathy was examined in 9 independent studies (4 from Japan including the original study, one Singaporean, one Korean, and two European) with type 2 diabetes. One case-control study involving European patients with type 1 diabetes was included. The frequency of the T allele for SNP rs2268388 was consistently higher among patients with type 2 diabetes and proteinuria. A meta-analysis revealed that rs2268388 was significantly associated with proteinuria in Japanese patients with type 2 diabetes (p = 5.35 x 10(-8), odds ratio = 1.61, 95% Cl: 1.35-1.91). Rs2268388 was also associated with type 2 diabetes-associated end-stage renal disease (ESRD) in European Americans (p = 6 x 10(-4), odds ratio = 1.61, 95% Cl: 1.22-2.13). Significant association was not detected between this SNP and nephropathy in those with type 1 diabetes. A subsequent in vitro functional analysis revealed that a 29-bp DNA fragment, including rs2268388, had significant enhancer activity in cultured human renal proximal tubular epithelial cells. Fragments corresponding to the disease susceptibility allele (T) had higher enhancer activity than those of the major allele. These results suggest that ACACB is a strong candidate for conferring susceptibility for proteinuria in patients with type 2 diabetes.

<h2>Abstract</h2> Although insulin autoimmune syndrome (IAS) was found to be strongly related with methimazole, rapidly increasing numbers of cases with alpha lipoic acid-induced IAS have been confirmed to be reported since 2003. As alpha lipoic acid has gained popularity as a supplement for dieting and anti-aging, a warning should be issued.

Organic cation transporter 1 (OCT1; SLC22A1) seems to play a role in the efficacy and disposition of the widely used antidiabetic drug metformin. Genetic variants in OCT1 have been identified largely in European populations. Metformin is increasingly being used in Asian populations where the incidence of type 2 diabetes (T2D) is on the rise. The goal of this study is to identify genetic variants of OCT1 in Chinese and Japanese populations, which may potentially modulate response to metformin. We used recent data from the 1000 Genomes Project (Chinese and Japanese) and direct sequencing of selected amplicons of OCT1 in 66 DNA samples from Japanese patients with T2D. A total of six nonsynonymous variants were identified. Three of them (Q97K, P117L, and R206C) had not been functionally characterized previously and had allele frequencies of 0.017, 0.023 and 0.008, respectively. The uptake of metformin in cells expressing Q97K, P117L, and R206C was significantly reduced relative to the OCT1 reference (62 ± 4.3, 55 ± 6.8, and 22 ± 1.5% for Q97K, P117L, and R206C, respectively). Kinetic studies indicated that P117L and R206C exhibited a reduced V(max), whereas Q97K showed an increased K(m). The green fluorescent protein (GFP)-tagged Q97K and P117L variants localized to the plasma membrane, whereas the GFP-tagged R206C was retained mainly in the endoplasmic reticulum. Replacement of the highly conserved R206 with different amino acids modulated the subcellular localization and function of the transporter. This study suggests that nonsynonymous variants of OCT1 in Chinese and Japanese populations may affect the differential response to metformin.

Objective: To evaluate long-term safety and efficacy of tofogliflozin in Japanese patients with type 2 diabetes as monotherapy or in combination with other oral antidiabetic agents, we conducted 52-week, open-label, randomized controlled trials. Research design and methods: The single-agent trial included patients with inadequate glycemic control on diet and exercise, whereas the add-on trial included those uncontrolled with any of the oral antidiabetic agents. In both trials, patients were randomly assigned to receive tofogliflozin 20 or 40 mg once daily orally for 52 weeks. Main outcome measures: Safety assessments. Results: A total of 194 patients (65, 20-mg group; 129, 40-mg group) were enrolled into the single-agent trial, whereas 602 (178 and 424, respectively) were enrolled into the add-on trial. Tofogliflozin was well tolerated for 52 weeks in both trials with < 6% of treatment discontinuation because of adverse events in each treatment group. It also reduced hemoglobin A1c. In the single-agent trial, mean reductions at 52 weeks were 0.67 and 0.66% in the 20- and 40-mg groups, respectively. In the add-on trial, mean reductions ranged from 0.71 to 0.93% across the subgroups by dose and background therapy. Conclusion: Tofogliflozin was well tolerated and showed sustained efficacy in both trials.

OBJECTIVE To investigate the association between aortic stiffness and incident albuminuria and the decline in estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS We investigated 461 Japanese type 2 diabetic patients, comprising 199 women and 262 men, with a mean age of 59 ± 11 years. Patients were divided into two groups according to the median value of carotid-femoral pulse wave velocity (cf-PWV), which was used to evaluate aortic stiffness. The end point was defined as the transition from normo- to microalbuminuria or micro- to macroalbuminuria. The Cox proportional hazard model was used to calculate the hazard ratio (HR) and 95% CI. The correlation between cf-PWV and rate of change in eGFR was also determined by linear regression analysis. RESULTS The baseline mean (± SD) cf-PWV was 9.6 ± 2.4 m/s. During a median follow-up period of 5.9 years (range 0.3–8.6), progression of albuminuria was observed in 85 patients. The 5-year cumulative incidence of the end point in patients with cf-PWV below and above the median was 8.5 and 19.4%, respectively (P = 0.002, log-rank test). cf-PWV was significantly associated with incident albuminuria (HR 1.23, 95% CI 1.13–1.33, P &amp;lt; 0.001) by multivariate Cox regression analysis. A significant association between cf-PWV and annual change in eGFR was also suggested by multiple linear regression analysis (standardized estimate −0.095, P = 0.031). CONCLUSIONS Aortic stiffness is associated with incident albuminuria and the rate of decline in glomerular filtration rate in type 2 diabetic patients.

To identify genetic elements that might confer susceptibility to diabetic nephropathy, we performed a genome-wide analysis of gene-based single nucleotide polymorphisms (SNPs) in a large cohort of Japanese patients with diabetes. In case-control association studies, patients with type 2 diabetes were divided into two groups, one having retinopathy as well as overt nephropathy and the other (the control group) having diabetic retinopathy but with no signs of renal involvement. Genotyping of these patients at >55,000 SNP loci indicated a gene encoding solute carrier family 12 member 3 (SLC12A3) to be a good candidate for the susceptibility to diabetic nephropathy, in view of a significant association of one landmark SNP located in the 24th intron (chi(2) = 15.4, P = 0.000087, odds ratio = 2.53 [95% CI 1.57-4.09]). Subsequent analysis of additional genetic variations in this gene identified several SNPs that were significantly associated with nephropathy, especially one in exon 23 (+78 G to A: Arg913Gln, chi(2) = 18.5, P = 0.00002, odds ratio = 2.53 [95% CI 1.64-3.90]). The results implicated that substitution of Arg913 to Gln in the SLC12A3 gene might reduce the risk to develop diabetic nephropathy and suggested that the gene product might be a potential target for the prevention or treatment of this disease.

OBJECTIVE Because early-onset Japanese NIDDM patients (diagnosed before age 30 years) can develop diabetic end-stage renal failure (ESRF) in their thirties, this study was performed to elucidate the incidence and determinants for the development of diabetic nephropathy. RESEARCH DESIGN AND METHODS The incidence of diabetic nephropathy and its relationship to baseline characteristics and long-term metabolic control were determined in 426 early-onset Japanese NIDDM patients who were followed for a mean of 6.8 years. RESULTS Of these 426 patients, 41 developed diabetic nephropathy manifested by persistent proteinuria (incidence rate [95%CI]/1,000 person-years; 14.1 [10.4–19.1]). Among patients whose mean HbA1c (measured by a high-performance chromatography method that is standardized and comparable to the one used in the Diabetes Control and Complications Trial study) was around 7% or less, few developed nephropathy. The incidence of nephropathy increased with increasing mean HbA1c level in a dose-dependent manner (χ2 trend = 49.9, P &amp;lt; 0.0001). Diastolic blood pressure and duration of diabetes at entry had significant predictive effects independent of metabolic control. CONCLUSIONS The incidence rate of diabetic nephropathy in early-onset Japanese NIDDM patients is potentially high, similar to or higher than that in Pima Indian NIDDM or Caucasian IDDM patients of comparable age. Diabetic nephropathy in NIDDM patients aged in their thirties or forties is likely to be an early feature that leads to ESRF, and this would contribute to the marked increase in the number of new patients with diabetic ESRF in Japan. NIDDM is a serious disease if near-normal glycemia is not achieved.

Although genetic susceptibility plays an important role in the pathogenesis of type 2 diabetes, most of the genes that influence susceptibility to type 2 diabetes have yet to be identified. Krüppel-like transcription factors are known to play important roles in development and cell differentiation, and have recently been implicated in the pathogenesis of type 2 diabetes. The present study aimed to examine the associations of single nucleotide polymorphisms (SNPs) in genes encoding members of the Krüppel-like-factor (KLF) family with type 2 diabetes in a large cohort of Japanese subjects.We genotyped 33 SNP loci found in 12 KLF genes in subjects with type 2 diabetes and in subjects from the general population using the PCR-Invader assay. We also examined the effects of the overexpression of KLF7 on adipogenesis in 3T3-L1 cells.We identified a significant association between an SNP in KLF7 and type 2 diabetes (A vs C: p=0.004 after Bonferroni's correction, odds ratio=1.59, 95% CI 1.27-2.00). The expression of Klf7 decreased in response to the differentiation of 3T3-L1 adipocytes, and the overexpression of KLF7 resulted in significant inhibition of adipogenesis in 3T3-L1 cells.These results indicate that the gene encoding KLF7 is a novel candidate for conferring genetic susceptibility to type 2 diabetes.

Transcription factor 7-like 2 (TCF7L2) has been shown to be associated with type 2 diabetes mellitus in multiple ethnic groups. Regarding the Asian population, Horikoshi et al. (Diabetologia 50:747–751, 2007) and Hayashi et al. (Diabetologia 50:980–984, 2007) reported that single nucleotide polymorphisms (SNPs) in TCF7L2 were associated with type 2 diabetes in the Japanese population, while contradictory results were reported for Han Chinese populations. The aim of this study was to investigate the associations of the TCF7L2 gene with type 2 diabetes using a relatively large sample size: 2,214 Japanese individuals with type 2 diabetes and 1,873 normal controls. The minor alleles of rs7903146, rs11196205, and rs12255372 showed significant associations with type 2 diabetes (OR = 1.48, P = 2.7 × 10−4; OR = 1.39, P = 4.6 × 10−4; OR = 1.70, P = 9.8 × 10−5, respectively) in the combined sample sets. However, neither rs11196218 nor rs290487 showed a significant association. These results indicate that TCF7L2 is an important susceptibility gene for type 2 diabetes in the Japanese population.

Abstract Objective: To investigate which features of eating disorders are associated with retinopathy and nephropathy in Type 1 diabetic females with clinical eating disorders. Method: Participants were 109 Type 1 diabetic females with clinical eating disorders diagnosed by the structured clinical interview for DSM‐IV (bulimia nervosa [ n = 70], binge‐eating disorder [ n = 28], anorexia nervosa [ n = 7], and eating disorder not otherwise specified [ n = 4]). Retinopathy and nephropathy were screened and demographic, medical, and eating disorder related factors were investigated. To identify the factors associated with each complication, logistic regression analysis was done. Results: Duration of severe insulin omission and duration of Type 1 diabetes were significantly associated with retinopathy (odds ratios = 1.35 and 1.23, respectively) and nephropathy (odds ratio = 1.35 and 1.21, respectively) in multivariate regression analyses. Conclusion: Of the various problematic behavioral factors related to eating disorders, the duration of severe insulin omission was the factor most closely associated with the retinopathy and nephropathy of Type 1 diabetic females with clinical eating disorders by multivariate analysis. This finding may help patients who deliberately omit insulin become aware of medical risk of insulin omission. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord, 2008

We evaluated the prevalence and risk factors for erectile dysfunction (ED) and interest in ED treatment among Japanese men being treated for type 2 diabetes mellitus. Patients (40-79 years; n=1118) completed the 5-item version of the International Index of Erectile Function (IIEF-5), and questions related to interest in ED pharmacotherapy, subjective symptoms of diabetes, and general quality of life. A separate survey completed by physicians examined the relationships between age, diabetic treatments (insulin or oral), symptoms of diabetes (poor glycemic control, microangiopathy), complications of diabetes (hypertension, ischemic heart disease, cerebrovascular disease), and ED. The prevalence of ED in patients with diabetes was 90%, a rate double that of non-diabetic individuals. Multivariate analyses revealed that age, insulin therapy, microangiopathy, hypertension, history of cerebrovascular or cardiovascular disease, leg dysesthesia, dysuria, insomnia, and anorexia all represented significant risk factors for ED. Half of all respondents were interested (29%) or would consider pharmacotherapy for ED (21%). These findings suggest that ED is a significant problem in Japanese men with diabetes, and that specific risk factors increase the prevalence of ED. Furthermore, the survey results expose national attitudes toward treatment of ED.

Aim: To confirm the efficacy of vildagliptin in patients with type 2 diabetes (T2D) by testing the hypothesis that glycosylated haemoglobin (HbA1c) reduction with vildagliptin is superior to that with voglibose after 12 weeks of treatment. Methods: In this 12‐week, randomized, double‐blind, active‐controlled, parallel‐group study, the efficacy and safety of vildagliptin (50 mg bid, n = 188) was compared with that of voglibose (0.2 mg tid, n = 192) in patients with T2D who were inadequately controlled with diet and exercise. Results: The characteristics of two groups were well matched at baseline. The mean age, body mass index (BMI) and HbA1c were 59.1 years, 24.9 kg/m 2 and 7.6%, respectively. At baseline, fasting plasma glucose (FPG) and 2‐h postprandial glucose (PPG) were 9.01 mmol/l (162.2 mg/dl) and 13.57 mmol/l (244.3 mg/dl), respectively. The adjusted mean change in HbA1c from baseline to endpoint was −0.95 ± 0.04% in the vildagliptin‐treated patients and −0.38 ± 0.04% in those receiving voglibose (between‐group change = 0.57 ± 0.06%, 95% confidence interval (CI) (−0.68 to −0.46%), p &lt; 0.001), showing that vildagliptin was superior to voglibose. Endpoint HbA1c ≤ 6.5% was achieved in 51% vildagliptin‐treated patients compared with 24% patients who were on voglibose (p &lt; 0.001). Vildagliptin also exhibited significantly (p &lt; 0.001) greater reduction compared with voglibose in both FPG [1.34 vs. 0.43 mmol/l (24.1 vs. 7.8 mg/dl)] and 2‐h PPG [2.86 vs. 1.1 mmol/l (51.5 vs. 19.8 mg/dl)]. Overall adverse events (AEs) were lower in the vildagliptin‐treated patients compared with that in the voglibose‐treated patients (61.2 vs. 71.4%), with no incidence of hypoglycaemia and serious adverse events with vildagliptin. Gastrointestinal AEs were significantly lower with vildagliptin compared with that of the voglibose (18.6 vs. 32.8%; p = 0.002). Conclusions: Vildagliptin (50 mg bid) showed superior efficacy and better tolerability compared with voglibose in Japanese patients with T2D.

Prediction of the disease status is one of the most important objectives of genetic studies. To select the genes with strong evidence of the association with type 2 diabetes mellitus, we validated the associations of the seven candidate loci extracted in our earlier study by genotyping the samples in two independent sample panels. However, except for KCNQ1, the association of none of the remaining seven loci was replicated. We then selected 11 genes, KCNQ1, TCF7L2, CDKAL1, CDKN2A/B, IGF2BP2, SLC30A8, HHEX, GCKR, HNF1B, KCNJ11 and PPARG, whose associations with diabetes have already been reported and replicated either in the literature or in this study in the Japanese population. As no evidence of the gene-gene interaction for any pair of the 11 loci was shown, we constructed a prediction model for the disease using the logistic regression analysis by incorporating the number of the risk alleles for the 11 genes, as well as age, sex and body mass index as independent variables. Cumulative risk assessment showed that the addition of one risk allele resulted in an average increase in the odds for the disease of 1.29 (95% CI=1.25-1.33, P=5.4 x 10(-53)). The area under the receiver operating characteristic curve, an estimate of the power of the prediction model, was 0.72, thereby indicating that our prediction model for type 2 diabetes may not be so useful but has some value. Incorporation of data from additional risk loci is most likely to increase the predictive power.

OBJECTIVE To assess the relationship between albuminuria, including elevation within the normal range, and decline in glomerular filtration rate (GFR) in diabetic patients. RESEARCH DESIGN AND METHODS A total of 5,449 Japanese diabetic patients were categorized according to sex and urinary albumin-to-creatinine ratio (ACR; <5, 5-9, 10-29, 30-99, 100-299, 300-999, 1,000-2,999, and > or =3,000 mg/g) and followed for at least 5 years. The rate of change in estimated GFR (eGFR) adjusted for age and baseline eGFR was compared among ACR categories. RESULTS A higher baseline ACR predicted a faster decline in eGFR for both sexes. Even within the normal range (<30 mg/g), ACR > or =10 mg/g in women and > or =5 mg/g in men was associated with a significantly greater rate of decline in eGFR relative to subjects with ACR <5 mg/g. CONCLUSIONS Elevated ACR, even within the normal range, is associated with a faster decline in eGFR in diabetic patients.

Sirtuin is a member of the nicotinamide adenine dinucleotide (NAD)-dependent deacetylases, and has been reported to play a pivotal role in energy expenditure, mitochondrial function and pathogenesis of metabolic diseases, including aging kidneys. In this study, we focused on the genes encoding sirtuin families, and examined the association between single nucleotide polymorphisms (SNPs) within genes encoding sirtuin families and diabetic nephropathy.We examined 52 SNPs within the SIRT genes (11 in SIRT1, 7 in SIRT2, 14 in SIRT3, 7 in SIRT4, 9 in SIRT5, and 4 in SIRT6) in 3 independent Japanese populations with type 2 diabetes (study 1: 747 cases (overt proteinuria), 557 controls; study 2: 455 cases (overt proteinuria) and 965 controls; study 3: 300 cases (end-stage renal disease) and 218 controls). The associations between these SNPs were analyzed by the Cochran-Armitage trend test, and results of the 3 studies were combined with a meta-analysis. We further examined an independent cohort (195 proteinuria cases and 264 controls) for validation of the original association.We identified 4 SNPs in SIRT1 that were nominally associated with diabetic nephropathy (P < 0.05), and subsequent haplotype analysis revealed that a haplotype consisting of the 11 SNPs within SIRT1 locus had a stronger association (P = 0.0028).These results indicate that SIRT1 may play a role in susceptibility to diabetic nephropathy in Japanese subjects with type 2 diabetes.

Objective Insulin is recommended as an appropriate treatment in type 2 diabetes patients with suboptimal glycemic control; however, its initiation is often delayed. We therefore conducted the DAWN (Diabetes Attitudes, Wishes and Needs) JAPAN study in an attempt to identify specific patient- and physician-related factors which contribute to delay of insulin initiation among Japanese patients with diabetes. In this report, we explored barriers for physicians which prevent timely insulin initiation. Methods The DAWN JAPAN study is a multicenter, questionnaire-based survey, conducted between 2004 and 2005. Participating physicians were categorized as follows based on their expertise: Japan Diabetes Society (JDS) certified specialists (n = 77), JDS-affiliated physicians (n = 30), and non-JDS-affiliated physicians (n = 27). To assess physician barriers to insulin initiation, we have used a newly developed 27- item questionnaire. Results The mean age of patients (n = 11,656) treated by participating physicians was 64.1 years. The mean duration of diabetes was 121.6 months, and their mean HbA1c was 7.5%. Insulin was used in 27.4% of total patients. With regard to physician barriers to insulin initiation, the biggest differences in concerns expressed by JDS-certified specialists and non-JDS-affiliated physicians were observed in the following items with statistical significance: “I do not have staff (nurse, pharmacists) who can assist with explanations” (1.3% vs 55.5%, respectively), “I have concerns about the use of insulin therapy in elderly patients” (38.1% vs 81.5%), and “It is difficult to provide guidance and education on insulin injection to patients” (16.9% vs 55.5%). The mean HbA1c at which physicians responded they would recommend insulin to their patients was 8.7%; however, they would reduce this level to 8.2% if they themselves required insulin. Conclusions Our results demonstrated that physicians have concerns about insulin use, and suggested that their concerns can lead to delay of insulin initiation.

OBJECTIVE The aim was to investigate the relationships between skin autofluorescence (AF) and the impact of past glycemic control and microvascular complications in Japanese patients with type 1 diabetes. RESEARCH DESIGN AND METHODS Two hundred forty-one patients and 110 controls were enrolled. Advanced glycation end product accumulation was measured with AF reader. Three monthly HbA1c levels during the past 20 years were determined from medical records, and the HbA1c area under the curve (AUC) was calculated. We performed multivariate regression analyses to examine the associations between the severity of diabetes complications and various variables. RESULTS Skin AF values increased with increasing the severity of retinopathy (P &amp;lt; 10−11, linear regression analysis) and nephropathy (P &amp;lt; 10−5 for chronic kidney disease stage; P &amp;lt; 10−5 for albuminuria-based stage). HbA1c AUC values over the past 15 years were significantly correlated with skin AF values (past 5 years: R = 0.35, P &amp;lt; 0.0001; past 10 years: R = 0.36, P &amp;lt; 0.0001; past 15 years: R = 0.55, P &amp;lt; 0.0001; past 20 years: R = 0.22, P = 0.13). HbA1c AUC values over the past 3, 5, 10, and 15 years were significantly associated with the severity of both nephropathy and retinopathy. Multivariate analyses in which HbA1c AUC value was removed from the independent variables indicated that only skin AF was independently associated with nephropathy, whereas age at registration, age at onset of diabetes, and skin AF were independently associated with retinopathy. CONCLUSIONS Skin AF reflects past long-term glycemic control and may serve as a surrogate marker for the development of microvascular complications in place of HbA1c AUC value.

Heterozygous mutations in the transcription factors hepatocyte nuclear factor (HNF)-1 alpha, HNF-1 beta, and HNF-4 alpha are associated with maturity-onset diabetes of the young (MODY) and are believed to cause this form of diabetes by impairing pancreatic beta-cell function. The HNFs also play a central role in the tissue-specific regulation of gene expression in liver and kidney, suggesting that patients with MODY due to a mutation in HNF-1 alpha, HNF-1 beta, or HNF-4 alpha may exhibit abnormal liver or kidney function. Here, we have examined liver and kidney function in a series of Japanese patients with HNF-4 alpha/MODY1, HNF-1 alpha/MODY3, and HNF-1 beta/MODY5 diabetes.Clinical and biochemical data were obtained from Japanese subjects with HNF-1 alpha, HNF-1 beta, and HNF-4 alpha diabetes. The clinical data included information on BMI, age at diagnosis, current treatment, and the presence and nature of any complications. The biochemical studies examined liver and kidney function and included measures of alanine and aspartate aminotransferase, gamma-glutamyl transpeptidase, blood urea nitrogen, creatinine, uric acid, total and HDL cholesterol, triglycerides, and 17 serum proteins.The present age and duration of diabetes were similar in patients with HNF-1 alpha, HNF-1 beta, or HNF-4 alpha diabetes, as was the age at diagnosis of diabetes in the youngest generation. All subjects were lean. Of the subjects with HNF-1 alpha and HNF-4 alpha diabetes, 50% were treated with insulin, as were all three subjects with HNF-1 beta diabetes. Retinopathy was present in patients with each form of diabetes. None of the subjects with HNF-4 alpha diabetes had evidence of nephropathy, whereas 36% of the patients with HNF-1 alpha diabetes and 100% of those with HNF-1 beta diabetes showed diminished kidney function. The three subjects with HNF-1 beta diabetes also had abnormally high serum creatinine, uric acid, and blood urea nitrogen levels, which are consistent with impaired kidney function, and one of seven subjects with HNF-1 alpha diabetes had a mild elevation in creatinine and blood urea nitrogen levels. These values were within the normal range in the three patients with HNF-4 alpha diabetes. Although the HNFs play a role in regulating the expression of the genes for most, if not all, serum proteins, there was no decrease in the levels of any of the 17 serum proteins examined, and most were within or slightly above the normal range. Lipoprotein(a) [Lp(a)] levels were elevated in the three patients with HNF-4 alpha diabetes and in one patient with HNF-1 beta diabetes, and in a second patient with HNF-1 beta diabetes, Lp(a) was at the upper limit of normal.The results indicate that as in white patients, MODY resulting from mutations in the HNF-1 alpha, HNF-1 beta, and HNF-4 alpha genes in Japanese patients may be a severe disease similar to classic type 2 diabetes. In addition, they suggest that patients with HNF-1 beta diabetes may be characterized by diminished kidney function and perhaps abnormal liver function. Further studies are needed to determine whether tests of liver and kidney function will be useful in the diagnosis and subclassification of MODY.

Hepatocyte nuclear factor-4α (HNF-4α) is a member of the nuclear receptor superfamily, a class of ligand-activated transcription factors. A nonsense mutation in the gene encoding this transcription factor was recently found in a white family with one form of maturity-onset diabetes of the young, MODY1. Here, we report the exonintron organization and partial sequence of the human HNF-4α gene. In addition, we have screened the 12 exons, flanking introns and minimal promoter region for mutations in a group of 57 unrelated Japanese subjects with early-onset NIDDM/MODY of unknown cause. Eight nucleotide substitutions were noted, of which one resulted in the mutation of a conserved arginine residue, Argl27 (CGG)→Trp (TGG) (designated R127W), located in the T-box, a region of the protein that may play a role in HNF-4α dimerization and DNA binding. This mutation was not found in 214 unrelated nondiabetic subjects (53 Japanese, 53 Chinese, 51 white, and 57 African-American). The R127W mutation was only present in three of five diabetic members in this family, indicating that it is not the only cause of diabetes in this family. The remaining seven nucleotide substitutions were located in the proximal promoter region and introns. They are not predicted to affect the transcription of the gene or mRNA processing and represent polymorphisms and rare variants. The results suggest that mutations in the HNF-4α gene may cause early-onset NIDDM/MODY in Japanese but they are less common than mutations in the HNF-1α/MODY3 gene. The information on the sequence of the HNF-4α gene and its promoter region will facilitate the search for mutations in other populations and studies of the role of this gene in determining normal pancreatic β-cell function.

To compare cross‐cultural differences of dental health behavior, 376 dental students in Japan and 213 in Australia were surveyed using a twenty‐item Hiroshima University‐Dental Behavior Inventory (HU‐DBI) questionnaire (in Japanese and English versions respectively). The mean DBI score of Year 1 Australian students was significantly greater than that of their Japanese peers (Australian 6.56, Japanese 5.57; P &lt; 0.001), which suggested a higher level of dental health awareness in Australian students on entry. Only 7 percent of the Japanese students had been told by their dentist that they were performing a high level of plaque control, as contrasted with 50 percent of the Australian students. Furthermore, while only a small proportion of the Australian students (8 percent) reported a belief that they may eventually require dentures, 37 percent of the Japanese students held this belief (P &lt; 0.001). The mean HU‐DBI score of the Japanese students was lower than that of the Australian students until Year 4. Differences between the genders were not a major feature.

Interleukin-1 (IL-1) is a potent mediator of inflammation and is known to induce bone resorption. We studied the effects of sex hormones on the function of human monocytes and demonstrated that prostaglandin E2 (PGE2) production was enhanced by progesterone and estradiol. As PGE2 has been shown to suppress the production of IL-1 by monocytes, it was speculated that sex hormones also modify the production of IL-1 by regulating PGE2 production. Thus, the effects of sex hormones on the production of IL-1 from human peripheral monocytes and the influence of PGE2 were investigated.Mononuclear leukocytes were obtained from 22 healthy adults. Progesterone, 17-beta estradiol (estradiol), and testosterone were used as representative sex hormones. Monocytes were incubated at 37 degrees C in air with 5% CO2 for 24 hours in RPMI 1640 medium with sex hormones at the designated concentrations. LPS (Salmonella typhimurium) was used to stimulate the monocytes at a concentration of 10 microg/ml. The concentrations of IL-1alpha and IL-1beta in the medium were determined by enzyme-linked immunosorbent assay kits. The concentration of PGE2 was determined using a direct radio-immunoassay kit. Indomethacin was used to inhibit the synthesis of PGE2 and eliminate its effect on the production of IL-1.Estradiol at concentrations of 0.04 ng/ml or more significantly reduced both IL-1alpha and IL- 1beta production. Progesterone also reduced IL-1alpha and IL-1beta production significantly at concentrations of 0.1 ng/ml or more and 0.02 ng/ml or more, respectively. The reductions in IL- 1alpha and IL-1beta production by sex hormones were not affected by addition of indomethacin.Estradiol and progesterone inhibited the production of IL-1 from human peripheral monocytes. The inhibition was not the result of enhanced production of PGE2. Under conditions in which sex hormone levels are low, monocytes produce IL- more readily in response to stimulation by LPS than high levels of such hormones. Low concentrations of sex hormones may be considered as one of the risk factors for periodontitis.

The relationship between the geographic distribution of susceptibility genes to insulin autoimmune syndrome (IAS) and the incidence of insulin autoimmune syndrome was investigated in order to examine the distribution of the genetic background to susceptibility to certain diseases. The HLA-DR4 allele, DRB1*0406, is associated with increased susceptibility to IAS among Japanese, while the DRB1*0403 and DRB1*0407 alleles are not (the odds ratio of which are 1.6 and 1.1, respectively). The worldwide geographic distribution of the three DR*04 alleles showed that the distribution of DRB1*0403 encompassed that of DRB1*0406 and DRB1*0407. Taken together with the findings that Glu at position 74 in the DRB1 molecule is shared by the three DRB1*04 alleles, there are only a few differences between the DRB1 molecule-nucleotide sequences of DRB1*0403, DRB1*0406 and DRB1*0407, and that all the three DRB1*04 alleles are carried by the same class II haplotype, DQA1*0301/DQB1*0302, it may be considered that DRB1*0403 is the ancestral allele of DRB1*0406 and DRB1*0407. Therefore, populations with a higher prevalence of DRB1*0406 have a higher risk of developing IAS. The extremely low prevalence of IAS among Caucasians can be explained by the low prevalence of DRB1*0406 in this population. This is a good example of the association between the predisposition to risk of development of certain diseases and the evolution of susceptibility genes.

To search a gene(s) conferring susceptibility to type 2 diabetes mellitus, we genotyped nearly 60,000 gene-based SNPs for Japanese patients and found evidence that the gene at chromosome 6p12 encoding transcription-factor-activating protein 2beta (TFAP2B) was a likely candidate in view of significant association of polymorphism in this gene with type 2 diabetes. Extensive analysis of this region identified that several variations within TFAP2B were significantly associated with type 2 diabetes [a variable number of tandem repeat locus: chi(2)=10.9, P=0.0009; odds ratio=1.57, 95% CI 1.20-2.06, intron 1+774 (G/T); chi(2)=11.6, P=0.0006; odds ratio=1.60, 95% CI 1.22-2.09, intron 1+2093 (A/C); chi(2)=12.2, P=0.0004; odds ratio=1.61, 95% CI 1.23-2.11]. The association of TFAP2B with type 2 diabetes was also observed in the UK population. These results suggest that TFAP2B might be a new candidate for conferring susceptibility to type 2 diabetes and contribute to the pathogenesis of type 2 diabetes.

The HLA-DQ β-chain (DQB1) genes of 72 Japanese patients with insulin-dependent diabetes mellitus (IDDM) and 85 control subjects were studied with polymerase chain-reaction (PCR) amplification and allele-specific oligonucleotide hybridization. DQw4 (DQBBIank) and DQw9 (DQB3.3) were increased in IDDM patients compared with the control subjects, and DQB1.2, DQB1.9, and DQw7 (DQB3.1) were decreased. Thirty-five (48.6%) IDDM patients had both alleles carrying an aspartic acid at position 57 of the DQ β-chain (Asp 57), 35 (48.6%) were Asp 57/non-Asp 57 heterozygous, and 2 (2.8%) had non-Asp 57 alleles only. Of 85 control subjects, the respective values for these three genotypes were 49 (57.6%), 29 (34.1%), and 7 (8.2%), respectively. The high frequency of Asp 57 alleles in both IDDM and control subjects contrasts with data for Whites. Therefore, the Asp 57 hypothesis that the presence of an aspartic acid at position 57 of DQ β-chain provides protection against developing IDDM is not tenable for Japanese IDDM patients. The DRB1 gene, particularly position 57 of the DR β-chain, may contribute to IDDM susceptibility in Japanese.

AbstractPrevious results of our cDNA microarray analysis to look for genes whose expression level correlates well with in vitro tubulogenesis by NP31 endothelial cells revealed the transcription factor ATF3 known to be responsive to stress such as reactive oxygen species (ROS). Anti-ATF3 small interfering RNA gave an inhibitory influence on tube formation by NP31 cells expressing an activated form of the vascular endothelial growth factor receptor 1 (VEGFR-1) kinase. When expression of ATF3 was regulated under the control of tetracycline system in NP31 cells, they acquired the tubulogenic ability upon ATF3 induction. While ATF3 failed to induce expressions of VEGF and VEGFR, it regulated those of CDK2, CDK4, p8, plasminogen activator inhibitor 1, integrin α1, subunit and matrix metalloprotease MMP13. In H2O2-stimulated NP31 cells as well as endothelial cells of glomerulus and aorta of Otsuka-Long-Evans-Tokushima-Fatty diabetic model rats, concomitantly enhanced expressions of ATF3, PAI-1, and p8 were observed. Given the proposed hypothesis of the close linkage between diabetic angiopathy and ROS, those data suggest that ROS-associated diabetic complication may involve ATF3-mediated pathological angiogenesis. We thank O. N. Witte at the University of California—Los Angeles for the Tet constructs, Otsuka Pharmaceutical Co. for the OLETF animals, and S. Kobayashi for technical help. We also thank S. Fujii at Hokkaido University for providing PAI-1 promoter constructs and S. Morikawa for technical help in confocal microscopy.This work is supported by a grant-in-aid for scientific research on metal sensors (no. 12147210) from the Japanese government.

Interactions between advanced glycation endproducts (AGE) and the receptor for AGE (RAGE) have been implicated in the development of diabetic vascular complications. RAGE has two N-glycosylation sites in and near the AGE-binding domain, and G82S mutation in the second N-glycosylation motif was recently reported in human. In this study, we examined whether de-N-glycosylation or G82S of RAGE affect its ability to bind AGE and cellular response to AGE. Recombinant wild-type, de-N-glycosylation and G82S RAGE proteins were produced in COS-7 cells, purified and assayed for ligand-binding abilities. De-N-glycosylation at N81 and G82S mutation decreased Kd for glycolaldehyde-derived AGE to three orders of magnitude lower levels compared with wild-type. AGE-induced upregulation of VEGF mRNA was significantly augmented in endothelial cell-derived ECV304 cells expressing de-N-glycosylated and G82S RAGE when compared with wild-type expressor. Exposure to low glucose resulted in the appearance of RAGE proteins of deglycosylated size in wild-type RAGE-expressing cells and significantly enhanced glycolaldehyde-derived AGE-induced VEGF mRNA expression. De-N-glycosylation or G82S mutation of RAGE increases affinity for AGE ligands, and may sensitize cells or conditions with it to AGE.

We recently identified a naturally occurring soluble form of RAGE (the receptor for advanced glycation endproducts, receptor for AGE) in cultured human vascular cells, and named it endogenous secretory RAGE (esRAGE). esRAGE is generated by alternative RNA splicing and is able to capture AGE, and exerts protection against AGE-induced endothelial cell injury. In the present study, the presence of esRAGE in human circulation was demonstrated for the first time, and a highly sensitive and specific sandwich ELISA system for esRAGE was developed to see whether esRAGE could be related to an individual resistance to the development of diabetic vascular complications. Sera from 47 type 1 diabetic subjects without clinical nephropathy (urinary albumin excretion <300mg/g creatinine) and 55 healthy controls were analyzed by the ELISA. Circulating esRAGE concentrations in diabetic patients with simple and proliferative retinopathy (0.09+/-0.02ng/mL, n=16 and 0.08+/-0.02ng/mL, n=8, respectively) were significantly lower than in those without retinopathy (0.13+/-0.06ng/mL, n=23). The results indicate that esRAGE can be a useful biomarker to indicate individual variations in susceptibility to diabetic retinopathy.

Anaemia has been suggested to be an independent risk factor for subsequent progression of advanced diabetic nephropathy; however, the relationship between haemoglobin levels and progression of nephropathy in patients without clinical albuminuria is unknown. We conducted this prospective hospital-based cohort study of 464 type 2 diabetic patients (149 women and 315 men, 55±13 [mean±SD] years of age) with serum creatinine <177 μmol/l (2.00 mg/dl) and urinary albumin : creatinine ratio <300 mg/g creatinine. GFR was estimated using the equation formulated by the Modification of Diet in Renal Disease Study group, refitted for Japanese individuals. Most patients had haemoglobin concentrations in the normal range (144±15 g/l), only modest renal impairment (GFR: 74.8±14.5 ml min−1 1.73 m−2), and normal urinary albumin levels (81.5/18.5% with normo-/microalbuminuria). The primary outcome measurement was the rate of change in GFR determined by regression analysis with GFR as a function of time. Patients were followed up for a mean observation period of 5.0±0.9 (range: 2.5 to 6.2) years. Univariate and multiple regression analyses yielded a significant association between the rate of change in GFR and baseline haemoglobin concentration. After adjusting for covariates, the rate of decline in GFR was significantly greater in patients in the lowest haemoglobin quartile (−3.27 ml min−1 1.73 m−2 year−1) than in the third (−2.71 ml min−1 1.73 m−2 year−1, p=0.024) and highest quartiles (−2.78 ml min−1 1.73 m−2 year−1, p=0.046). Lower haemoglobin concentrations in type 2 diabetic patients without clinical albuminuria may be a significant predictor of subsequent decline in GFR.

The Incipient to Overt: Angiotensin II Blocker, Telmisartan, Investigation on Type 2 Diabetic Nephropathy (INNOVATION) study previously showed that treatment with telmisartan, an angiotensin II receptor blocker, effectively reduced the transition from incipient to overt nephropathy in Japanese type 2 diabetic patients. However, that large study included both normotensive and hypertensive patients. In the present post hoc analysis, we aimed to assess whether or not telmisartan elicits beneficial effects on the progression of microalbuminuria in normotensive patients. We randomized 163 microalbuminuric (urinary albumin-to-creatinine ratio: UACR of 100 to 300 mg/g creatinine) normotensive type 2 diabetic patients to treatment with telmisartan (40 or 80 mg once daily) or placebo over 52 weeks. The patients treated with either dose of telmisartan showed lower transition rates from microalbuminuria to overt nephropathy compared to the placebo group. In addition, more patients on telmisartan reverted to normoalbuminuria (UACR<30 mg/g creatinine): 15.5% of the 40 mg group, 19.6% of the 80 mg group, and 1.9% of the placebo group. In normotensive patients treated with telmisartan, changes in UACR were not significantly correlated with changes in blood pressure. Side effects did not differ among the groups. The present study demonstrates that telmisartan prevents the progression of microalbuminuria (in some cases induces remission of albuminuria) in normotensive Japanese patients with type 2 diabetes. Telmisartan is shown to be safe and well tolerated in these patients.

Aims We examined whether glycated hemoglobin (HbA1C) levels of Japanese diabetic patients showed seasonal fluctuations. Methods Subjects included 2511 diabetic patients who regularly visited a single diabetic outpatient clinic for 10 years. A total of 253,477 HbA1C measurements, as well as sex, age, BMI, type of diabetes, and mode of therapy were extracted from a hospital-based database. For the cross-sectional and longitudinal analyses, average monthly HbA1C values of subjects and amplitudes of seasonal fluctuations were calculated. For the time-series analysis, seasonal adjustment factors of each subject were classified as complete, incomplete, or no fluctuation. Results Subjects showed a clear seasonal fluctuation of HbA1C levels, with highest levels in March (7.69%) and lowest levels in August (7.46%; p < 0.001). The amplitudes of the seasonal fluctuations were associated with the mean HbA1C levels. The time-series analysis showed that 78.3% of patients had complete or incomplete seasonal fluctuations. HbA1C levels were highest in winter–spring and lowest in summer–autumn in most patients; however, some patients showed a reverse pattern. Conclusions Seasonal fluctuations of HbA1C levels were recognized in most of the Japanese diabetic patients. Physiological or metabolic factors related to temperature may be the main cause of seasonal fluctuations in HbA1C levels.

Insulin receptors and several biological effects of insulin were measured in H35 and HTC cells, two rat hepatoma lines in permanent cell culture that have been employed previously to study glucocorticoid action. In H35 cells, insulin at concentrations as low as 1 pM both enhanced tyrosine amino-transferase activity and stimulated [3H]uridine incorporation into RNA. In this cell line, the binding of approximately 10 molecules of insulin/cell was sufficient to elicit these two biological responses. In contrast, in HTC cells, much higher concentrations of insulin (3 nM or greater) were needed to stimulate both tyrosine aminotransferase activity and other biological functions. When insulin receptors were measured, both cell types had a major insulin-binding site with a Kd of approximately 20 nM. H35 cells, however, had approximately 6 times more receptors per cell than HTC cells. In both cell types, insulin degradation was minimal. These findings indicate that several biological functions in H35 cells are extremely sensitive to insulin in vitro. In contrast, HTC cells are much less sensitive to the hormone. This lack of sensitivity in HTC cells most likely reflects a decrease in the number of insulin receptors present. In addition, the very large differences in responsiveness suggest that postreceptor alterations are also operative.

Genetic factors are believed to contribute to the development and progression of diabetic nephropathy. Recently, a genome-wide association study for diabetic nephropathy revealed four novel candidate loci in European American subjects with type 1 diabetes. In this study, we determined the association of the four loci with diabetic nephropathy in Japanese subjects with type 2 diabetes.We genotyped 11 singlenucleotide polymorphisms (SNPs) in four distinct loci (rs39059 and rs39075 in the CPVL/CHN2, rs1888747 and rs10868025 in FRMD3, rs739401 and rs451041 in CARS, and rs1041466, rs1411766, rs6492208, rs7989848, and rs9521445 in a chromosome 13q locus) in four independent Japanese populations.Six SNPs were nominally associated with diabetic nephropathy in one of the four Japanese populations (P < 0.05; rs451041 in study 1; rs39059 and rs1888747 in study 3; rs1411766 in studies 1 and 4; and rs7989848 and rs9521445 in study 4); however, no significant association was observed for any SNP after correction for multiple testing errors in the individual populations. Nevertheless, a meta-analysis performed for the data obtained from all four populations revealed that one SNP (rs1411766) in chromosome 13q was significantly associated with diabetic nephropathy in the Japanese populations (nominal P = 0.004, corrected P = 0.04, odds ratio 1.26 [95% CI = 1.07-1.47]).Our results suggest that the rs1411766 locus may be commonly involved in conferring susceptibility to diabetic nephropathy among subjects with type 1 or type 2 diabetes across different ethnic groups.

Recent advances in genome research have enabled the identification of new genomic variations that are associated with type 2 diabetes mellitus (T2DM). Via fine mapping of SNPs in a candidate region of chromosome 21q, the current study identifies potassium inwardly-rectifying channel, subfamily J, member 15 (KCNJ15) as a new T2DM susceptibility gene. KCNJ15 is expressed in the β cell of the pancreas, and a synonymous SNP, rs3746876, in exon 4 (C566T) of this gene, with T allele frequency among control subjects of 3.1%, showed a significant association with T2DM affecting lean individuals in three independent Japanese sample sets (p = 2.5 × 10−7, odds ratio [OR] = 2.54, 95% confidence interval [CI] = 1.76–3.67) and with unstratified T2DM (p = 6.7 × 10−6, OR = 1.76, 95% CI = 1.37–2.25). The diabetes risk allele frequency was, however, very low among Europeans in whom no association between this variant and T2DM could be shown. Functional analysis in human embryonic kidney 293 cells demonstrated that the risk allele of the synonymous SNP in exon 4 increased KCNJ15 expression via increased mRNA stability, which resulted in the higher expression of protein as compared to that of the nonrisk allele. We also showed that KCNJ15 is expressed in human pancreatic β cells. In conclusion, we demonstrated a significant association between a synonymous variant in KCNJ15 and T2DM in lean Japanese patients with T2DM, suggesting that KCNJ15 is a previously unreported susceptibility gene for T2DM among Asians. Recent advances in genome research have enabled the identification of new genomic variations that are associated with type 2 diabetes mellitus (T2DM). Via fine mapping of SNPs in a candidate region of chromosome 21q, the current study identifies potassium inwardly-rectifying channel, subfamily J, member 15 (KCNJ15) as a new T2DM susceptibility gene. KCNJ15 is expressed in the β cell of the pancreas, and a synonymous SNP, rs3746876, in exon 4 (C566T) of this gene, with T allele frequency among control subjects of 3.1%, showed a significant association with T2DM affecting lean individuals in three independent Japanese sample sets (p = 2.5 × 10−7, odds ratio [OR] = 2.54, 95% confidence interval [CI] = 1.76–3.67) and with unstratified T2DM (p = 6.7 × 10−6, OR = 1.76, 95% CI = 1.37–2.25). The diabetes risk allele frequency was, however, very low among Europeans in whom no association between this variant and T2DM could be shown. Functional analysis in human embryonic kidney 293 cells demonstrated that the risk allele of the synonymous SNP in exon 4 increased KCNJ15 expression via increased mRNA stability, which resulted in the higher expression of protein as compared to that of the nonrisk allele. We also showed that KCNJ15 is expressed in human pancreatic β cells. In conclusion, we demonstrated a significant association between a synonymous variant in KCNJ15 and T2DM in lean Japanese patients with T2DM, suggesting that KCNJ15 is a previously unreported susceptibility gene for T2DM among Asians.

Non-alcoholic fatty liver disease (NAFLD) is a common condition, in which abnormal amounts of triglycerides accumulate in hepatocytes and is closely related to cardiovascular diseases and diabetes. Dietary fats contribute 15% of fat accumulation in the liver and regulate hepatic lipid metabolism. The supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) improves NAFLD. The aim of this study is to assess the cross-sectional association between dietary n-3 PUFAs and NAFLD in Japanese men and women.Participants were middle-aged, apparently healthy, 296 men and 496 women, who did not drink alcohol and who participated in a general health check-up program. Dietary information from the previous month was obtained by the brief-type self-administered diet history questionnaire. NAFLD was diagnosed if abdominal ultrasonography revealed the presence of fatty liver.The prevalence of NAFLD was 45.3% in men and 17.5% in women. In comparison with the first tertile, multivariate adjusted odds ratios (95% confidence intervals) for the presence of NAFLD in the second and third tertiles for men taking eicosapentaenoic acid (EPA) were 0.59 (0.31-1.14) and 0.45 (0.23-0.90), respectively, (P for linear trend=0.024), and the multivariate adjusted odds ratios (95% confidence intervals) for the presence of NAFLD in the second and third tertiles for men taking EPA+docosahexaenoic acid (DHA) were 0.44 (0.23-0.86) and 0.48 (0.24-0.95), respectively, (P for linear trend=0.035). However, there was no significant relation between NAFLD and each of these nutrients in women.Dietary EPA and EPA+DHA may be independent and preventive nutrients for NAFLD in Japanese men.

We collated and analysed data from hospital records regarding the cause of death of 18,385 patients with diabetes who died in 282 medical institutions throughout Japan over the 10-year period between 1991 and 2000. Autopsy was carried out in 1750 cases. The most frequent cause of death in all 18,385 cases was malignant neoplasia, accounting for 34.1% of cases, followed by vascular diseases (including diabetic nephropathy, ischemic heart diseases and cerebrovascular diseases) in 26.8%, infections in 14.3%, and then diabetic coma in 1.2%. The most common malignancy was liver cancer, accounting for 8.6% of all the deaths. Of the deaths from vascular diseases, diabetic nephropathy was the cause of death in 6.8% of cases, and the frequency as cause of death for ischemic heart diseases and cerebrovascular diseases were similar at 10.2% and 9.8%, respectively. Myocardial infarction accounted for almost all the deaths from ischemic heart diseases, whereas deaths from cerebral infarction were 2.2-fold as common as those from cerebral hemorrhage. In the analyses of the relationship between age and causes of death in diabetic patients who underwent autopsy, the overall mortality rate as a result of vascular diseases increased with age, although the mortality rates from diabetic nephropathy and cerebrovascular diseases increased little from the fifth decade of life. The mortality rate from ischemic heart diseases increased with age, however, and was higher than the other forms of vascular diseases from the sixth decade of life, accounting for approximately 50% of vascular deaths in the eighth decade. Malignant neoplasia was the most frequent cause of death from the fifth decade of life, and was extremely common in the seventh decade, accounting for 46.3% of all the deaths. The mortality rate from infections varied little between age groups from the fifth decade of life. In the analyses of glycemic control and the age at the time of death, lifespans were 2.5 years shorter in males, and 1.6 years shorter in female diabetics with poor glycemic control than in those with good or fair glycemic control. This difference was greater for deaths as a result of infections and vascular diseases, particularly diabetic nephropathy, than for malignant neoplasia. Analysis of the relationship between glycemic control and the duration of diabetes and deaths as a result of vascular diseases showed no correlation between the level of glycemic control and death from diabetic nephropathy, ischemic heart diseases or cerebrovascular diseases. In diabetics with disease durations of less than 10 years, the mortality rate from macroangiopathy was higher than that as a result of diabetic nephropathy, a form of microangiopathy. Treatment for diabetes comprised of diet alone in 21.5%, oral hypoglycemic agents in 29.5%, and insulin with or without oral hypoglycemic agents in 44.2%, which was the most common. In particular, 683/1170 (58.4%) diabetics who died from diabetic nephropathy were on insulin therapy, a higher proportion than the 661/1687 (39.2%) who died from ischemic heart diseases, or the 659/1622 (40.6%) who died from cerebrovascular diseases. The average age at the time of death in the survey population was, 68 years for males and 71.6 years for females. These were 9.6 and 13 years, respectively, short of the average life expectancy for the Japanese general population. In comparison with the previous survey (1981-1990), the average age at the time of death had increased 1.5 years for males, and 3.2 years for females. The average life expectancy for the Japanese general population had also increased 1.7 and 2.7 years, respectively, over that period, showing that advances in the management and treatment of diabetes have not led to any improvement in patients' life expectancies. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00019.x, 2010).

We explored whether visit-to-visit variability in both glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) simultaneously predicted the development of microalbuminuria and retinopathy, and whether the predictive ability of these measurements changed according to mean HbA1c and SBP levels in people with type 2 diabetes.A retrospective observational cohort study was conducted on 243 type 2 diabetes patients with normoalbuminuria and 486 without retinopathy at the first visit and within 1year thereafter. The two cohorts were followed up from 1995 until 2012. Multivariate and stratified analyses were performed using Cox proportional hazard models.Microalbuminuria developed in 84 patients and retinopathy in 108. Hazard ratios (HRs) for the development of microalbuminuria associated with the coefficient of variation (CV) and variation independent of mean (VIM) of both HbA1c and SBP significantly increased. In participants with a mean SBP <130mmHg, the HRs for the development of retinopathy associated with CV and VIM of HbA1c were abruptly elevated and significant compared with those with a mean SBP ≥130mmHg.Visit-to-visit variability in both HbA1c and SBP simultaneously predict the development of microalbuminuria. HbA1c variability may predict the development of retinopathy when the mean SBP is normal (<130mmHg).

The effects of sex hormones on the vitro production of prostaglandin (PG) E2 by monocytes were investigated. Monocytes were obtained from heparinized peripheral blood of healthy adults and incubated for 24 hours with lipopolysaccharide (LPS) and sex hormones. After incubation, the medium was assayed for PGE2 by means of radioimmunoassay. PGE2 production by monocytes was enhanced by progesterone. Estradiol reduced PGE2 production at 0.4 ng/ml, but enhanced it at 20 ng/ml. Testosterone reduced PGE2 production. The reduced PGE2 production by monocytes treated with 0.4 ng/ml of estradiol was restored to the control level by addition of progesterone at 20 ng/ml. These results suggest that sex hormones may modulate gingival inflammation mediated by PGE2.

CS-045, (+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramkethylchroman-2- ylmethoxy)benzyl]-2,4-thiazolidinedione, lowers plasma glucose in several animal models of non-insulin dependent diabetes mellitus (NIDDM) presumably by increasing insulin sensitivity. Little adverse effect was found in a phase 1 study on healthy male subjects. In order to test its efficacy in lowering plasma glucose in NIDDM in man, a pilot multi-center clinical trial of CS-045 was carried out in 146 patients with NIDDM whose glycemic control was inadequate (FPG greater than 140 mg/dl) on diet and/or other oral hypoglycemic agents. CS-045 was given orally in a daily dose of 200 mg or 400 mg for 12 weeks in addition to the previous treatment. The mean fasting plasma glucose (FPG) and fructosamine began to decrease within 2 weeks and the mean HbA1c within 8 weeks. After 12 weeks, the FPG fell from 192 +/- 41 to 155 +/- 45 mg/dl (P less than 0.01), fructosamine from 3.7 +/- 0.6 to 3.3 +/- 0.6 (P less than 0.01), and HbA1c from 8.9 +/- 1.5 to 8.1 +/- 1.5% (P less than 0.01). The drug was effective in 39% of patients in that FPG fell by more than 20% of the initial value. This rate of efficacy was the same when CS-045 was given alone or together with other oral hypoglycemic agents. The drug was more effective in a dosage of 400 mg than with 200 mg (the rate of efficacy 46% vs 25%) and more effective in obese patients than in lean patients (46% vs 25%).(ABSTRACT TRUNCATED AT 250 WORDS)

To investigate the mechanism of the cellular insulin insensitivity of diabetic rats, insulin binding, glucose transport, and glucose oxidation were studied in adipocytes from streptozotocin-diabetic rats. Increased insulin binding was found in cells from diabetic rats, and this was due to an increased number of insulin receptors rather than a change in receptor affinity. Basal and insulin-stimulated glucose oxidation was decreased in adipocytes from diabetic rats when the data are expressed in absolute terms or as percent increased above basal. Although the absolute rate of basal and insulin-stimulated glucose transport was decreased in adipocytes from diabetic rats, the percent increase above basal of insulin-stimulated glucose transport was not decreased. In conclusion, although the cellular insulin insensitivity exists in adipocytes from diabetic rats, the number of insulin receptors was increased, coupling between insulin receptors and the glucose transport system is intact in adipocytes from diabetic rats, and a defect in intracellular glucose metabolism rather than glucose transport plays a major role in the insulin insensitivity of adipocytes from diabetic rats.

In the present study, we have used isolated mouse pancreatic acini to investigate the relationship between 125I-insulin binding and its degradation in order to probe the nature and cellular localization of the degradative process. In these cells, the proteolysis of 125I-insulin was dependent on time and cell concentration, and was saturated by unlabeled insulin with a Km of 290 nM. Since this value was much higher than the Kd for insulin binding to its receptor (1.1 nM), the data indicated that 125I-insulin degradation by acini occurred primarily via nonreceptor mechanisms. Several lines of evidence suggested that insulin was being degraded by the neutral thiol protease, insulin degrading enzyme (IDE). First, insulin degradation was inhibited by thiolreacting agents such as N-ethylmaleimide and p-chloromercuribenzoate. Second, the Km for degradation in acini was similar to the reported Km for IDE in other tissues. Third, the enzyme activity had a relative mol wt of approximately 130,000 by gel filtration, a value similar to that reported for purified IDE. Fourth, the degrading activity was removed with a specific antibody to IDE. Other lines of evidence suggested that enzymes located on the cell surface played a role in insulin degradation by acini. First, the nonpenetrating sulfhydryl reacting agent 5,5′dithiobis-2-nitrobenzoic acid blocked 125I-insulin degradation. Second, a specific antibody to IDE identified the presence of the enzyme on the cell surface. Third, chloroquine, leupeptin and antipain, agents that inhibit lysosomal function, did not influence 125I-insulin degradation. Fourth, highly purified pancreatic plasma membranes degraded 125I-insulin.

Pancreatic acini were prepared from rats rendered diabetic with streptozotocin. In this tissue, insulin stimulated [3H]leucine incorporation into protein. The full effects of insulin on this function were not immediate but increased linearly with time for up to 2 h of incubation. Insulin had a detectable effect on l eucine incorporation at 50 pM, a half-maximal effect at 0.7 nM, and a maximal effect at 30 nM. Desdipeptide proinsulin was only 10% as potent as native insulin in stimulating [3H]leucine incorporation, whereas proinsulin and desoctapeptide insulin were only 1% as potent. Insulin also increased the incorporation of [3H]valine and [35S]methionine into protein but did not increase the influx of either [14C]cycloleucine or alpha-[3H]aminoisobutyric acid. These observations suggested that the increased incorporation of labeled amino acid into protein reflected stimulation of protein synthesis rather than stimulation of amino acid transport. Furthermore, insulin at 1.67 nM significantly increased the acinar cell concentration of amylase. The present findings are consistent therefore with the concept that insulin regulates pancreatic exocrine functions, including protein and enzyme synthesis.

Diabet. Med. 27, 1017–1023 (2010) Abstract Aims The relationship between type of diabetes and risk of chronic kidney disease has not been studied in detail. We conducted this study to determine the prevalence of chronic kidney disease in Japanese adults with diabetes, with a particular emphasis on the comparison of Type 1 and Type 2 diabetes. Methods We studied 3,575 Japanese patients with diabetes, 504 with Type 1 (mean ± SD age 38 ± 13 years; 350 women and 154 men) and 3071 with Type 2 diabetes (60 ± 13 years; 1187 women and 1884 men). Prevalence rates of albuminuria [urinary albumin/creatinine ratio (≥ 30 mg/g], decreased estimated glomerular filtration rate (eGFR &lt; 60 ml/min/1.73 m 2 ) and chronic kidney disease (defined as albuminuria and/or decreased eGFR) were compared between the two diabetic groups. Results The prevalence of albuminuria was higher in Type 2 than Type 1 diabetic patients by both Fisher’s exact test (36.1 vs. 15.9%, P &lt; 0.001) and multivariate logistic regression analysis [adjusted odds ratio (OR) = 1.482, 95% confidence interval (CI) = 1.050–2.091, P = 0.025]. The prevalence of decreased eGFR was also higher in Type 2 diabetic patients (25.2 vs. 7.9%, P &lt; 0.001); however, the statistical significance disappeared after adjusting for covariates, including age (OR = 0.656, 95% CI = 0.395–1.088, P = 0.102). The prevalence of chronic kidney disease was also higher in Type 2 diabetic patients (46.0 vs. 19.1%, P &lt; 0.001); however, the statistical significance disappeared in the multivariate analysis. Conclusions Type 2 diabetic patients are more than twice as likely as Type 1 diabetic patients to have chronic kidney disease due to an age‐independent higher prevalence of albuminuria and age‐dependent decreased eGFR.

It is unclear whether albuminuria and reduced glomerular filtration rate (GFR) independently increase the risk of incident stroke and coronary artery disease (CAD) in Japanese patients with diabetes. We investigated the independent effects of albuminuria and estimated GFR (eGFR) on the first occurrence of stroke and CAD in patients with type 2 diabetes mellitus (T2DM). We studied 1002 T2DM patients with eGFR (ml min⁻¹ per 1.73 m²) ≥15 and had no previous cardiovascular disease (CVD) history. GFR was estimated using the modified three-variable equation for the Japanese. Patients were divided into four eGFR categories: ≥90, 60-89, 30-59 and 15-29. The end point was an incident stroke and CAD events. The Cox proportional hazard model was used to calculate hazard ratio and 95% confidence interval. During a mean follow-up period of 5.2±2.1 years, 72 episodes of stroke and 90 of CAD were observed. Multivariate Cox analysis revealed no significant association between the eGFR category and incident stroke. The stroke hazard ratio (95% confidence interval) in reference to patients with an eGFR ≥90 was 0.78 (0.40-1.56) for patients with an eGFR of 60-89, 1.47 (0.70-3.10) for patients with an eGFR of 30-59 and 1.14 (0.39-3.35) for patients with an eGFR of 15-29. Reduced eGFR was a significant risk factor for CAD, with hazard ratios (95% confidence interval) for patients with an eGFRs of 60-89, 30-59 and 15-29 at 1.81 (1.01-3.57), 2.03 (1.04-4.40) and 3.01 (1.13-8.02), respectively. Reduced eGFR is independently associated with incident CAD but not stroke in Japanese patients with T2DM.

The aim of the present study was to investigate the specific relationship between hepatic steatosis and insulin resistance in the early stage of obesity. Among general health examinees who received an ultrasound scanning, 131 subjects without fatty liver (non-FL group) and 142 subjects with fatty liver (FL group) were selected so that both groups were matched for age, sex, body mass index, and % body fat. The FL group was then subdivided into 2 groups according to the severity of steatosis by ultrasound. Insulin resistance was assessed by homeostasis model assessment for insulin resistance, serum high-molecular-weight (HMW) adiponectin, and insulin-like growth factor binding protein 1 concentrations. Unexpectedly, the non-FL group showed higher waist circumference than the FL group. Nevertheless, homeostasis model assessment for insulin resistance as well as conventional insulin resistance indexes such as serum insulin, free fatty acid, and triglyceride levels demonstrated a stepwise increase, and HMW adiponectin and insulin-like growth factor binding protein 1 demonstrated a stepwise decrease with increasing degree of hepatic steatosis. Overall, insulin resistance markers correlated with obesity indexes, but only HMW adiponectin no longer showed any meaningful correlation in the presence of fatty liver. The prevalence of BP, fasting serum glucose, and high-density lipoprotein cholesterol above or below cutoff points and subjects having 2 or more metabolic syndrome components were higher in the moderate to severe FL group compared to the non-FL group. In conclusion, these results in nondiabetic and relatively normal–body mass index subjects suggest that hepatic steatosis is independently associated with insulin resistance regardless of extrahepatic adiposity and might be the earliest event in pathogenesis of the metabolic syndrome.

Potassium inwardly rectifying channel, subfamily J, member 15 (KCNJ15) is a type 2 diabetes–associated risk gene, and Kcnj15 overexpression suppresses insulin secretion in rat insulinoma (INS1) cells. The aim of the current study was to characterize the role of Kcnj15 by knockdown of this gene in vitro and in vivo. Human islet cells were used to determine the expression of KCNJ15. Expression of KCNJ15 mRNA in islets was higher in subjects with type 2 diabetes. In INS1 cells, Kcnj15 expression was induced by high glucose–containing medium. Regulation of Kcnj15 by glucose and its effect on insulin secretion were analyzed in INS1 cells and in normal mice and diabetic mice by the inactivation of Kcnj15 using small interfering RNA. Knockdown of Kcnj15 increased the insulin secretion in vitro and in vivo. KCNJ15 and Ca2+-sensing receptor (CsR) interact in the kidney. Binding of Kcnj15 with CsR was also detected in INS1 cells. In conclusion, downregulation of Kcnj15 leads to increased insulin secretion in vitro and in vivo. The mechanism to regulate insulin secretion involves KCNJ15 and CsR.

Background Some patients with diabetes have advanced diabetic glomerular lesions and progressive kidney function decline even if urinary albumin levels are in the normal range. Therefore, another prognostic marker for diabetic kidney disease needs to be identified. We aimed to clarify whether urinary type IV collagen is associated with the progression of kidney function decline in patients with type 1 diabetes. Study Design Hospital-based observational cohort study. Setting & Participants 231 normo- and microalbuminuric patients with type 1 diabetes who were younger than 40 years at the start of the study. Predictor & Measurements Urinary type IV collagen, determined using a 1-step sandwich enzyme immunoassay. Outcome The primary outcome measurement was rate of change in estimated glomerular filtration rate (eGFR). Results Mean follow-up was 7.4 ± 1.3 (standard deviation) years. Urinary type IV collagen-creatinine ratio (T4C) was associated significantly with rate of change in eGFR in both univariate (r = −0.169; P = 0.01) and multivariate regression analyses (standardized estimate = −0.131; P = 0.03). In the sensitivity analysis limited to patients with normoalbuminuria (n = 213), T4C, but not urinary albumin-creatinine ratio (ACR), was associated significantly with rate of change in eGFR (standardized estimate = −0.12; P = 0.03). The interaction between logarithmically transformed ACR and logarithmically transformed T4C on eGFR decline was not significant (P for interaction = 0.2). We compared the adjusted rate of change in eGFR among 4 groups classified according to normal or increased T4C and ACR values and found that the rate of decline in eGFR in patients with increased T4C and normal ACR values was significantly faster than that in patients with normal T4C and ACR values (−4.3 and −3.0 mL/min/1.73 m2/y; P = 0.004, analysis of covariance). Limitations Study size was relatively small. Conclusions T4C is associated with progression of kidney function decline in young patients with type 1 diabetes. Some patients with diabetes have advanced diabetic glomerular lesions and progressive kidney function decline even if urinary albumin levels are in the normal range. Therefore, another prognostic marker for diabetic kidney disease needs to be identified. We aimed to clarify whether urinary type IV collagen is associated with the progression of kidney function decline in patients with type 1 diabetes. Hospital-based observational cohort study. 231 normo- and microalbuminuric patients with type 1 diabetes who were younger than 40 years at the start of the study. Urinary type IV collagen, determined using a 1-step sandwich enzyme immunoassay. The primary outcome measurement was rate of change in estimated glomerular filtration rate (eGFR). Mean follow-up was 7.4 ± 1.3 (standard deviation) years. Urinary type IV collagen-creatinine ratio (T4C) was associated significantly with rate of change in eGFR in both univariate (r = −0.169; P = 0.01) and multivariate regression analyses (standardized estimate = −0.131; P = 0.03). In the sensitivity analysis limited to patients with normoalbuminuria (n = 213), T4C, but not urinary albumin-creatinine ratio (ACR), was associated significantly with rate of change in eGFR (standardized estimate = −0.12; P = 0.03). The interaction between logarithmically transformed ACR and logarithmically transformed T4C on eGFR decline was not significant (P for interaction = 0.2). We compared the adjusted rate of change in eGFR among 4 groups classified according to normal or increased T4C and ACR values and found that the rate of decline in eGFR in patients with increased T4C and normal ACR values was significantly faster than that in patients with normal T4C and ACR values (−4.3 and −3.0 mL/min/1.73 m2/y; P = 0.004, analysis of covariance). Study size was relatively small. T4C is associated with progression of kidney function decline in young patients with type 1 diabetes.

To investigate the association between long-term visit-to-visit variability in glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) and the incidence of cardiovascular disease (CVD) in patients with type 2 diabetes.We retrospectively enrolled 632 patients with type 2 diabetes and no history of CVD who first visited our hospital between 1995 and 1996, were followed-up for ≥1 year, attended at least 4 clinic visits and had at least 1 visit per year. Patients were followed until June 2012 at the latest, and mailed questionnaires.During the median follow-up period (15.4 years), 81 patients developed CVD. Multivariate analysis revealed that the coefficient of variation (CV) and the variation independent of mean (VIM) for HbA1c and SBP were significant predictors of CVD incidence independent of mean HbA1c and SBP. Patients were classified into 4 groups by median HbA1cCV and SBPCV values and by median HbA1cVIM and SBPVIM values. Among these groups, the HRs were highest in the high-HbA1cCV/high-SBPCV and high-HbA1cVIM/high-SBPVIM groups and were significantly higher compared with those in the low-HbA1cCV/low-SBPCV and low-HbA1cVIM/low-SBPVIM groups, respectively. Among patients with mean SBP≥130 mm Hg, the HRs associated with HbA1cCV and HbA1cVIM were drastically elevated compared with those with mean SBP<130 mm Hg (interaction p<0.05).Long-term visit-to-visit variability in HbA1c and SBP represented a combined and additive risk for CVD incidence in patients with type 2 diabetes. It is suggested that a synergistic effect exists between HbA1c variability and mean SBP levels for CVD incidence.

Abstract Aims/Introduction We evaluated the impact of postprandial hyperglycemia at clinic visits on the incidence of cardiovascular diseases ( CVD ) and all‐cause mortality independently of mean glycosylated hemoglobin in type 2 diabetes patients in a real‐world setting. Materials and Methods The present retrospective observational cohort study included 646 type 2 diabetes patients. All of the participants had their initial consultations at the Institute for Diabetes Care and Research, Asahi Life Foundation affiliated Marunouchi Hospital, Tokyo, Japan, during the period from 1995 to 1996, visited the clinic ≥4 times, had their 2‐h post‐breakfast blood glucose (2h‐ PBBG ) levels measured and were followed up for ≥1 year. The 646 patients were followed up for survival. Of the 646 patients, 618 had no history of CVD at the first visit and had measured 2h‐ PBBG until the first CVD onset or censorings. These two cohorts were followed up through June 2012, and subsequently questionnaires were mailed. Multivariate Cox proportional hazard models were used to evaluate the risk of CVD incidence and death. Results CVD occurred in 78 patients, and 56 patients died. The median follow‐up periods of the CVD cohort and the mortality cohort were 15.6 and 15.9 years, respectively. The mean 2h‐ PBBG is a significant predictor of the CVD incidence and all‐cause mortality after adjusting for the mean glycosylated hemoglobin, the number of 2h‐ PBBG measurements, age, sex and classical risk factors. Conclusions Postprandial hyperglycemia represented by the mean level of 2h‐ PBBG at clinic visits is associated with CVD incidence and all‐cause mortality independently of the mean glycosylated hemoglobin level in type 2 diabetes patients. Prospective interventional trials are warranted to confirm the present findings.

We have carried out an autosomal genome scan for genes contributing to the development of type 2 diabetes and affecting BMI in the Japanese population (164 families, 256 affected sib-pairs). We found 12 regions that showed nominally significant multipoint evidence of linkage with type 2 diabetes (i.e. logarithm of odds [LOD] score >0.59, P < 0.05): chromosome 1 29.9 cM; chromosome 2 169.6 and 236.8 cM; chromosome 4 104.9 cM; chromosome 5 114.8 cM; chromosome 6 42.3 cM; chromosome 8 15.3 and 93.3 cM; chromosome 9 140.0 cM; chromosome 11 131.6 cM; chromosome 17 36.1 cM; and chromosome 21 48.0 cM. Twelve regions showed nominal multipoint evidence for linkage with log-transformed BMI (lnBMI): chromosome 2 167.9 and 210.5 cM; chromosome 3 185.7 cM; chromosome 4 118.9 and 145.6 cM; chromosome 5 131.9 cM; chromosome 7 7.4 cM; chromosome 10 70.0 cM; chromosome 15 12.8 cM; chromosome 16 30.0 cM; and chromosome 17 47.8 and 100.2 cM. Although none of the regions achieved genome-wide levels of significance, simulation studies showed that we observed more linkage signals than expected if there were no loci contributing to type 2 diabetes or BMI. Eight of the regions showing nominal evidence for linkage with type 2 diabetes have been reported in other genome scans, and seven of the regions showing linkage with lnBMI have shown linkage with BMI and BMI-related traits in other studies. Thus, our results may replicate findings in other studies. They may also indicate new regions of the genome that are involved in the regulation of blood glucose levels or body weight.

To describe an "integrated inpatient therapy" for type 1 diabetic patients with recurrent binge eating and to assess its effectiveness for females with bulimia nervosa (BN).At the first visit to our outpatient clinic for treatment of an eating disorder and diabetes, type 1 diabetic females with BN underwent single session "outpatient counseling." All patients then returned to the referring physician for further treatment and observation. None of the BN patients had the minimum expected 1% fall in HbA1c and all were therefore encouraged to undergo our "integrated inpatient therapy." However, only patients accepting inpatient treatment on their own volition were admitted. An "INPATIENT" group (n=9) consisted of those who underwent inpatient therapy and had a 3-year follow-up period after discharge. The clinical course was assessed by the HbA1c and BMI course and by comparison of psychological/behavioral factors between baseline and follow-up. For reference, the clinical course of a "NON-INPATIENT" group (n=10), who did not have the inpatient therapy for at least 2 years after first visit, was also assessed.The "INPATIENTs" had significantly lower HbA1c; lower psychological test scores related to eating disorder psychopathology, depressiveness, and anxiety-proneness; a reduced frequency and amount of binge eating; and fewer patients exhibited purging behaviors at follow-up than at first visit. At follow-up, seven (78%) "INPATIENTs" no longer fulfilled any criterion for clinical or subclinical eating disorders. The "NON-INPATIENTs" had no significant improvement.The findings give interesting insights into the possibilities of "integrated inpatient therapy" as an effective treatment for type 1 diabetic females with BN.

Spontaneously hypertensive rats (SHR) are the most extensively used animal model for genetic hypertension, increased stroke damage, and insulin resistance syndromes; however, the identification of target genes has proved difficult.SHR show elevated sympathetic nerve activity, and stimulation of the central blood pressure control centers with glutamate or nicotine results in exaggerated blood pressure responses, effects that appear to be genetically determined.Kynurenic acid, a competitive glutamate antagonist and a non-competitive nicotinic antagonist, can be synthesized in the brain by the enzyme kynurenine aminotransferase-1 (KAT-1).We have previously shown that KAT-1 activity is significantly reduced in SHR compared with normotensive Wistar Kyoto rats (WKY).Here we show that KAT-1 contains a missense mutation, E61G, in all the strains of SHR examined but not in any of the WKY or outbred strains.Previous studies on F2 rats from a cross of stroke-prone SHR and WKY have shown a suggestive level of linkage between elevated blood pressure and the KAT-1 locus on chromosome 3.In addition, the mutant enzyme expressed in Escherichia coli displays altered kinetics.This mutation may explain the enhanced sensitivity to glutamate and nicotine seen in SHR that may be related to an underlying mechanism of hypertension and increased sensitivity to stroke.

Takii M, Uchigata Y, Kishimoto J, Morita C, Hata T, Nozaki T, Kawai K, Iwamoto Y, Sudo N, Kubo C. The relationship between the age of onset of type 1 diabetes and the subsequent development of a severe eating disorder by female patients. Objectives: To determine the age of onset of type 1 diabetes that is most closely related to the subsequent development of a severe eating disorder such as anorexia nervosa (AN) or bulimia nervosa (BN). Methods: Participants were 53 female type 1 diabetes patients with AN or BN referred to our outpatient clinic from the Diabetes Center of Tokyo Women's Medical University. Forty-nine female type 1 diabetes patients who regularly visited the Diabetes Center and had no eating disorder-related problems constituted the ‘direct control’ group, whereas 941 female patients who for the first time visited the Diabetes Center constituted the ‘historical control’ group. The kernel function method was used to generate a density estimation of the onset age of each group and the chi-square test was used to compare the distribution. Results: The control groups had similar density shapes for the onset age of type 1 diabetes, but both differed from the ‘eating disorder’ group. For onset age 7–18 yr, the density of the ‘eating disorder’ group was higher than those of the control groups, but for the younger and older onset ages the densities were lower. The ‘eating disorder’ group developed type 1 diabetes significantly more frequently than the ‘historical control’ group between 7 and 18 yr of age (χ2 = 9.066, p < 0.011). Conclusion: The development of type 1 diabetes in preadolescence or adolescence seems to place girls at risk for the subsequent development of AN or BN. Careful attention should be paid to these high-risk patients.

After the iv injection of 2 micrograms isoproterenol, peripheral plasma insulin and C-peptide concentrations were measured in 16 nonobese normal subjects and 53 maturity-onset diabetic subjects. Basal insulin (P < 0.01) and C-peptide (P < 0.05) levels were increased in obese diabetic subjects compared to nonobese normal subjects. Isoproterenol-stimulated insulin (P < 0.01) and C-peptide (P < 0.05) increments were increased in obese diabetic subjects compared to nonobese diabetic subjects. Hepatic insulin extraction, measured by comparing the ratios of insulin increment to C-peptide increment after isoproterenol injection, was decreased in both nonobese and obese diabetics compared to normals (P < 0.05). No significant differences in the ratios were found between nonobese and obese diabetics or between patients on diet or sulfonylurea therapy. Age, sex, duration of disease, familial predisposition to diabetes, and diabetic retinopathy did not influence the ratios. Isoproterenol-stimulated C-peptide increments (P < 0.05) and fasting blood glucose levels (P < 0.05) were decreased in diabetics showing decreased hepatic insulin extraction compared to diabetics with normal hepatic insulin extraction. Isoproterenol-stimulated insulin increments in diabetics showing decreased hepatic insulin extraction were higher than in normals (P < 0.05). These studies indicate that hepatic insulin extraction decreases in nonobese and obese diabetic subjects. It might be postulated that the lesser amount of secreted insulin is able to show biological activities more efficiently in diabetics with decreased hepatic insulin extraction.

Aims/Introduction: To reveal whether visit-to-visit variability in HbA1c is associated with higher risk of cardiovascular disease (CVD) in patients with type 2 diabetes. The study was conducted on 689 Japanese patients with type 2 diabetes [295 women, 394 men; mean (±standard deviations (SD)) age 65 ± 11 years]. Variability in HbA1c was evaluated as the intrapersonal SD of serial measurements of HbA1c during the follow-up period for at least 12 months. Patients were divided into quartiles according to the SD of HbA1c, and the primary endpoint was defined as incident CVD. Cox's proportional hazards model was used to calculate hazard ratios (HR) and 95% confidence intervals (CI). During a median follow-up period of 3.3 years (range 1.0-6.3 years), 26 ± 14 measurements of HbA1c were obtained per patient and 61 episodes of incident CVD were recorded. The 5-year cumulative incidence of CVD in patients across the first, second, third, and fourth quartiles of SD in HbA1c was 4.9, 8.7, 17.1, and 26.2%, respectively (P < 0.001, log-rank test). Multivariate Cox regression analysis revealed that the incidence of CVD was significantly higher in patients in the fourth quartile of SD in HbA1c compared with those in the first quartile (HR 3.38; 95% CI 1.07-10.63; P = 0.039), independent of mean HbA1c and other traditional cardiovascular risk factors. Variability of HbA1c may be a potent predictor of incident CVD in Japanese patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00155.x, 2011).

Background.The impact of serum lipid abnormalities on the progression of diabetic kidney disease (DKD) remains conflicting. Furthermore, gender differences in the association between dyslipidaemia and outcome of DKD are largely unknown. We therefore conducted this single-centre observational cohort study to clarify gender differences in the association between serum lipid profiles and the progression of DKD.

To better understand patient resistance to initiation of insulin therapy, this study examined the perception gap concerning initiation of insulin therapy between individuals with type 2 diabetes and their physicians by using data from the DAWN Japan study.The DAWN Japan study is a multi-center, questionnaire-based survey, conducted between 2004-2005. Patients recommended to start insulin therapy (n = 148) answered a questionnaire by rating degree of agreement with 16 statements concerning insulin therapy on a 5-point scale (1: strongly disagree to 5: strongly agree). Ratings of 1 and 2 were categorized as 'disagree' with a statement, and 3, 4, and 5 as 'agree'. Their attending physicians (n = 68) selected statements which could be associated with patient's concerns about insulin therapy.Nearly all the patients agreed with the statements 'I don't want to inject myself for the rest of my life' (95%), and 'I don't want to be bothered with doing injections' (90%); fewer than half agreed with 'My friendships may suffer' (46%), and 'I don't understand why insulin is necessary for me' (45%). Estimation by the physicians and the actual perceptions patients reported differed significantly for 13 statements. Physicians seemed to particularly under-estimate the impact associated with social aspects of insulin use (e.g., 'I don't want to be different from others', 55% patients vs 7% physicians). On the contrary, the statement 'Injections are painful' was the only concern over-estimated by the physicians.It was demonstrated that differences in perceptions regarding insulin therapy exist between physicians and patients, particularly in terms of social impacts. The data, obtained in 2004, may not precisely reflect the present situation, but still represents a barrier to insulin therapy widely held by patients and physicians. These results suggest that appropriate understanding of patients' concerns about insulin therapy is important to encourage timely insulin initiation.

We aimed to study the relationships among the copper (Cu)/zinc (Zn) ratio, inflammatory biomarkers, and the prevalence of diabetic kidney disease (DKD) in patients with type 2 diabetes.A cross-sectional study was performed on 651 patients with type 2 diabetes. DKD was defined as a urinary albumin-to-creatinine ratio of ≥30 mg/g creatinine and/or an estimated glomerular filtration rate using cystatin C of < 60 mL/min/1.73 m2 . Areas under the curves (AUCs), cutoff values, and thresholds for detecting DKD were determined for the Cu/Zn ratio, soluble tumor necrosis factor-α receptor 1 (sTNFαR1), and high-sensitivity C-reactive protein (hsCRP). Patients were categorized by each cutoff value of sTNFαR1 and the Cu/Zn ratio. Odds ratios (ORs) and biological interactions for the prevalence of DKD were determined.DKD was identified in 220 patients. AUC/optimal cutoff values were 0.777/1300 pg/mL for sTNFαR1, 0.603/1.1648 for the Cu/Zn ratio, and 0.582/305 ng/mL for hsCRP. The ORs for DKD were higher, but not significantly, in the sTNFαR1 < 1300 and Cu/Zn ≥ 1.1648 group, significantly higher in the sTNFαR1 ≥ 1300 and Cu/Zn < 1.1648 group (P < 0.0001), and further synergistically elevated in the sTNFαR1 ≥ 1300 and Cu/Zn ≥ 1.1648 group (P < 0.0001) compared with the sTNFαR1 < 1300 and Cu/Zn < 1.1648 group after multivariable adjustment. Levels of sTNFαR1 were significantly higher in the sTNFαR1 ≥ 1300 and Cu/Zn ≥ 1.1648 group than in the sTNFαR1 ≥ 1300 and Cu/Zn < 1.1648 group (P = 0.0006).Under an inflammatory initiation signal of elevated serum sTNFαR1 levels, an increase in the Cu/Zn ratio may further exacerbate inflammation and is synergistically associated with a high prevalence of DKD in patients with type 2 diabetes.

To investigate the association of oxidized low-density lipoprotein (ox-LDL) with the development of diabetic nephropathy, plasma levels of ox-LDL were measured in 70 patients with type 2 diabetes mellitus. A sandwich enzyme-linked immunoadsorbent assay (ELISA) using the mouse monoclonal antibody FOH1a/DLH3, which specifically recognizes oxidized phosphatidylcholine, and a horseradish peroxidase (HRP)-labeled goat anti-human apolipoprotein B IgG was used to measure ox-LDL levels. The mean age of the patients was 57.0+/-1 3.4 years, and the mean duration of diabetes was 13.4+/-8.5 years. Plasma ox-LDL levels were similar in patients with normoalbuminuria (13.7+/-3.9 U/ml), patients with microalbuminuria (12.8+/-3.9 U/ml), and normal controls (12.5+/-4.2 U/ml). However, the plasma ox-LDL level in patients with macroalbuminuria (16.8+/-7.5 U/ml) was significantly higher than those in the other groups (P<0.05). Hemoglobin A1c (HbA1c) levels were similar in diabetic patients with normoalbuminuria (8.2+/-2.2%), microalbuminuria (7.8+/-1.3%), or macroalbuminuria (7.2+/-1.4%). There was no significant correlation between the ox-LDL level and the HbA1c level. The significantly elevated plasma ox-LDL levels in patients with macroalbuminuria suggest that ox-LDL may play an important role in the progression of diabetic nephropathy.

Abstract Background Regenerating gene (Reg) product, Reg, acts as an autocrine/paracrine growth factor for beta‐cell regeneration. The presence of autoimmunity against REG may affect the operative of the regenerative mechanisms in beta cells of Type 1 and Type 2 diabetes patients. We screened sera from Type 1 and Type 2 diabetes subjects for anti‐REG autoantibodies, searched for correlations in the general characteristics of the subjects with the presence of anti‐REG autoimmunity, and tested the attenuation of REG‐induced beta‐cell proliferation by the autoanitibodies. Material and methods We examined the occurrence of anti‐REG autoantibodies in patients’ sera (265 Type 1, 368 Type 2 diabetes patients, and 75 unrelated control subjects) by Western blot analysis, and evaluated inhibitory effects of the sera on REG‐stimulated beta‐cell proliferation by a 5′‐Bromo‐2′‐deoxyuridine (BrdU) incorporation assay in vitro . Results Anti‐REG autoantibodies were found in 24·9% of Type 1, 14·9% of Type 2 and 2·7% of control subjects ( P = 0·0004). There were significant differences between the autoantibody positive and negative groups in the duration of disease in the Type 1 subjects ( P = 0·0035), and the age of onset in the Type 2 subjects ( P = 0·0274). The patient sera containing anti‐REG autoantibodies significantly attenuated the BrdU incorporation by REG (35·6 ± 4·06% of the control), whereas the nondiabetic sera without anti‐REG autoantibodies scarcely reduced the incorporation (88·8 ± 5·10%). Conclusion Anti‐REG autoantibodies, which retard beta‐cell proliferation in vitro , are found in some diabetic patients. Thus, autoimmunity to REG may be associated with the development/acceleration of diabetes in at least some patients.

Patients with type 2 diabetes are known to have abnormalities in their remnant metabolism and low density lipoprotein (LDL) subfraction pattern, with a preponderance of small dense LDL. The effects of pitavastatin, a newly synthesized 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, on lipoprotein profiles in patients with type 2 diabetes were determined. Thirty-three patients were treated with pitavastatin with a daily dose of 2 mg for 8 weeks. After treatment, triglyceride, total and LDL cholesterol were significantly reduced by 28.7 +/- 36.7%, 25.2 +/- 14.3% and 36.1 +/- 14.3%, respectively. Remnant-like particle cholesterol (RLP-C), an independent risk factor for CAD which is known to be elevated in diabetic patients, was also significantly reduced (-30.9 +/- 30.5%) by the treatment and this decrease correlated well with the decrease in triglyceride level. The proportion of small dense LDL, which is known for its atherogenisity, decreased from 29.9 +/- 26.2% to 19.7 +/- 22.7% and the mean LDL particle size significantly increased from 26.36 +/- 1.13 nm to 27.10 +/- 1.36 nm. Pitavastatin, which is known to improve triglyceride levels and cholesterol levels, also improves RLP-C level and LDL subfraction profiles, and this in turn may reduce the cardiovascular risk in patients with type 2 diabetes and dyslipidemia.

A mitochondrial tRNA Leu(UUR) mutation at nucleotide 3,243 is known to be found in most patients with MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes) and has also been identified in several families with maternally inherited diabetes mellitus and hearing loss. We report here audiologic features in patients with hearing loss associated with the mutation. Four patients without and five with MELAS were studied. Most of the patients had bilateral progressive sensorineural hearing loss. The most common shape of the audiogram was sloping, while cases in the advanced stages had flat audiograms. Speech discrimination scores were generally poor and did not parallel the degree of hearing loss. The present study suggests that the lesion for hearing loss could include both cochlear and retrocochlear involvement, but does not demonstrate a significant difference in the audiologic findings between patients with and without MELAS.

The evaluation of iron status in dialysis patients provides information essential to the planning of adequate recombinant human erythropoietin (rHuEPO) treatment. Iron status of the patients can be determined from the recently available measurement of content of reticulocyte hemoglobin (CHr).In this study, to clarify the accuracy of CHr in diagnosing iron deficiency in hemodialysis (HD) patients, we initially compared CHr with such conventional iron parameters as serum ferritin levels, transferrin saturation and serum soluble transferrin receptor levels. Secondly, we investigated the changes in CHr during iron supplementation for iron-deficient patients to determine whether this marker is a prospective and reliable indicator of iron sufficiency. The participants in this study were 149 hemodialysis (HD) patients and 53 age-matched healthy subjects. Iron deficiency was defined as having a TSAT of less than 20% and serum ferritin of less than 100 ng/ml. Conventional parameters of red blood cells and CHr were measured by an ADVIA120 autoanalyzer.Mean CHr was 32.3 +/- 2.2 pg in the patients undergoing hemodialysis treatment. CHr significantly correlated with iron parameters in the dialysis patients. Logistic regression analysis was performed to determine the relationship between CHr and each outcome measure, and CHr was the significant multivariate predictor of iron deficiency. Iron supplements given to the patients with low CHr and hematocrit (Hct) significantly increased Hct, resulting in a decrease in the weekly dosage of rHuEPO.CHr, measured simultaneously with Hct, is a sensitive and specific marker of iron status in dialysis patients.

Tubulointerstitial damage plays a crucial role in the progression of kidney diseases, including diabetic nephropathy (1). Among several distinct types of fatty acid–binding protein (FABP), liver-type FABP (l-FABP) is abundantly expressed in hepatocytes and constitutively expressed in proximal tubular cells of the kidney (2). l-FABP incorporates albumin-bound free fatty acids (FFAs) that are filtered through the glomeruli into proximal tubular cells and transports FFAs from the cytosol to the nucleus (3). In transgenic mice expressing human l-FAPB, protein overload, resulting in massive proteinuria, upregulated renal l-FABP expression and increased its urinary excretion (4), suggesting that urinary l-FABP may reflect tubulointerstitial damage. Recently, in patients with nondiabetic glomerular disease, urinary excretion of l-FABP increased in parallel with the severity of tubulointerstitial injury and correlated with proteinuria and the rate of progression of renal disease, suggesting that l-FABP may be a useful indicator for the progression of nondiabetic kidney disease (4,5). To determine the clinical significance of l-FABP in patients with diabetic nephropathy, we conducted a cross-sectional study comparing urinary l-FABP excretion in diabetic patients with serial stages of kidney disease. Adult patients with type 2 diabetes were recruited from the outpatient clinic of the Division of Nephrology and Hypertension, Diabetes Center, Tokyo Women’s Medical University …

This study was performed to examine whether patients with type 2 diabetes have cognitive deficits associated with the prefrontal cortex (PFC).Twenty-seven middle-aged patients with newly diagnosed type 2 diabetes and 27 healthy controls underwent physical measurements and neuropsychological tasks. Response inhibition, reward prediction, and executive function were assessed by the Go/NoGo task, the reversal and extinction tasks, and the Wisconsin Card Sorting Test (WCST). To examine the interactions of being overweight with diabetes on cognitive performance, performance data were analysed by two-way ANCOVA with diabetes and overweight as factors and age as a covariate.Patients with type 2 diabetes showed significantly decreased response inhibition in the Go/NoGo task (discriminability index: P = 0.001). There was an interaction of being overweight with diabetes on reaction time in the Go trials of the Go/NoGo task (P = 0.009). Being overweight was related to retained responses to the presentiment of reward in the extinction task (P = 0.029). The four groups showed normal cognitive performance in the WCST.Our results showed that middle-aged, newly diagnosed and medication-free patients with type 2 diabetes have a particular neuropsychological deficit in inhibitory control of impulsive response, which is an independent effect of diabetes apart from being overweight.

In 169 Japanese patients with type 2 diabetes mellitus with blood glucose levels that were inadequately controlled with diet and exercise therapy alone, or with diet and exercise therapy plus a sulfonylurea (SU) drug, we evaluated the safety and efficacy of global standard dose metformin given up to a maximum daily dose of 2250 mg for 54 weeks. The changes in HbA1c from baseline to the final evaluation visit were -1.32 ± 0.76% for metformin monotherapy and -1.29 ± 0.81% for metformin plus SU, both significantly lower than baseline. The incidences of adverse events and adverse drug reactions were 91.1% (154/169 patients) and 67.5% (114/169 patients), respectively. The most common adverse events were gastrointestinal symptoms, and most of the gastrointestinal symptoms were considered by investigators to be related to metformin treatment. An increased blood lactic acid level was observed in three subjects (1.8%); however, no clinical symptoms were reported, and there was no increase in mean lactic acid concentration throughout the evaluation period. Symptoms of hypoglycemia were reported in 16 patients, all receiving metformin plus SU, but none received metformin monotherapy. There was a decrease in mean body weight. Global standard dose metformin may be useful for maintaining good blood glucose control over the long term in the treatment of type 2 diabetes mellitus in Japanese patients.