ϟ

Chi Xu

Here are all the papers by Chi Xu that you can download and read on OA.mg.
Chi Xu’s last known institution is . Download Chi Xu PDFs here.

Claim this Profile →
DOI: 10.1038/nature17412
2016
Cited 663 times
Potentiating the antitumour response of CD8+ T cells by modulating cholesterol metabolism
Modulating cholesterol metabolism can improve CD8+ T-cell-mediated immunity against tumours; genetic or pharmacological inhibition of the cholesterol esterification enzyme ACAT1 led to higher plasma membrane cholesterol levels, better T-cell receptor clustering and signalling, improved immunological synapse maturation, and enhanced antitumour activity in mice. This study reports a new approach to cancer immunotherapy through the modulation of T cell cholesterol metabolism. Chenqi Xu and colleagues demonstrate that inhibition of the cellular cholesterol esterification pathway in mice, either by genetic ablation or by pharmacological inhibition of acetyl-CoA acetyltransferase 1 (ACAT1) and ACAT2, increases plasma membrane cholesterol levels, T-cell receptor clustering and signalling, and significantly potentiates the antitumour response of CD8+ T cells in mice. To test the potential of ACAT1 as a drug target for cancer immunotherapy, the authors treated melanoma-bearing mice with avasimibe, an ACAT inhibitor that has been used to treat atherosclerosis in clinical trials. An antitumour effect was observed and a combination of avasimibe and anti-PD-1 antibody was more effective than either alone. CD8+ T cells have a central role in antitumour immunity, but their activity is suppressed in the tumour microenvironment1,2,3,4. Reactivating the cytotoxicity of CD8+ T cells is of great clinical interest in cancer immunotherapy. Here we report a new mechanism by which the antitumour response of mouse CD8+ T cells can be potentiated by modulating cholesterol metabolism. Inhibiting cholesterol esterification in T cells by genetic ablation or pharmacological inhibition of ACAT1, a key cholesterol esterification enzyme5, led to potentiated effector function and enhanced proliferation of CD8+ but not CD4+ T cells. This is due to the increase in the plasma membrane cholesterol level of CD8+ T cells, which causes enhanced T-cell receptor clustering and signalling as well as more efficient formation of the immunological synapse. ACAT1-deficient CD8+ T cells were better than wild-type CD8+ T cells at controlling melanoma growth and metastasis in mice. We used the ACAT inhibitor avasimibe, which was previously tested in clinical trials for treating atherosclerosis and showed a good human safety profile6,7, to treat melanoma in mice and observed a good antitumour effect. A combined therapy of avasimibe plus an anti-PD-1 antibody showed better efficacy than monotherapies in controlling tumour progression. ACAT1, an established target for atherosclerosis, is therefore also a potential target for cancer immunotherapy.
DOI: 10.1126/science.287.5452.498
2000
Cited 501 times
A Critical Role for Murine Complement Regulator Crry in Fetomaternal Tolerance
Complement is a component of natural immunity. Its regulation is needed to protect tissues from inflammation, but mice with a disrupted gene for the complement regulator decay accelerating factor were normal. Mice that were deficient in another murine complement regulator, Crry, were generated to investigate its role in vivo. Survival of Crry-/- embryos was compromised because of complement deposition and concomitant placenta inflammation. Complement activation at the fetomaternal interface caused the fetal loss because breeding to C3-/- mice rescued Crry-/- mice from lethality. Thus, the regulation of complement is critical in fetal control of maternal processes that mediate tissue damage.
DOI: 10.1038/nature12058
2013
Cited 337 times
Follicular T-helper cell recruitment governed by bystander B cells and ICOS-driven motility
DOI: 10.1038/cddis.2014.430
2014
Cited 254 times
MicroRNA-30d regulates cardiomyocyte pyroptosis by directly targeting foxo3a in diabetic cardiomyopathy
Diabetic cardiomyopathy is a common cardiac condition in patients with diabetes mellitus, which can result in cardiac hypertrophy and subsequent heart failure, associated with pyroptosis, the pro-inflammatory programmed cell death. MicroRNAs (miRNAs), small endogenous non-coding RNAs, have been shown to be involved in diabetic cardiomyopathy. However, whether miRNAs regulate pyroptosis in diabetic cardiomyopathy remains unknown. Our study revealed that mir-30d expression was substantially increased in streptozotocin (STZ)-induced diabetic rats and in high-glucose-treated cardiomyocytes as well. Upregulation of mir-30d promoted cardiomyocyte pyroptosis in diabetic cardiomyopathy; conversely, knockdown of mir-30d attenuated it. In an effort to understand the signaling mechanisms underlying the pro-pyroptotic property of mir-30d, we found that forced expression of mir-30d upregulated caspase-1 and pro-inflammatory cytokines IL-1β and IL-18. Moreover, mir-30d directly repressed foxo3a expression and its downstream protein, apoptosis repressor with caspase recruitment domain (ARC). Furthermore, silencing ARC by siRNA mimicked the action of mir-30d: upregulating caspase-1 and inducing pyroptosis. These findings promoted us to propose a new signaling pathway leading to cardiomyocyte pyroptosis under hyperglycemic conditions: mir-30d↑→foxo3a↓→ ARC↓→caspase-1↑→IL-1β, IL-18↑→pyroptosis↑. Therefore, mir-30d may be a promising therapeutic target for the management of diabetic cardiomyopathy.
DOI: 10.18632/oncotarget.8063
2016
Cited 175 times
Long noncoding RNA H19 indicates a poor prognosis of colorectal cancer and promotes tumor growth by recruiting and binding to eIF4A3
The overall biological role and clinical significance of long non-coding RNA H19 in colorectal cancer (CRC) remain largely unknown. Here, we firstly report that the lncRNA H19 recruits eIF4A3 and promotes the CRC cell proliferation. We observed higher expression of H19 was significantly correlated with tumor differentiation and advanced TNM stage in a cohort of 83 CRC patients. Multivariate analyses revealed that expression of H19 served as an independent predictor for overall survival and disease-free survival. Further experiments revealed that overexpression of H19 promoted the proliferation of CRC cells, while depletion of H19 inhibited cell viability and induced growth arrest. Moreover, expression profile data showed that H19 upregulated a series of cell-cycle genes. Using bioinformatics prediction and RNA immunoprecipitation assays, we identified eIF4A3 as an RNA-binding protein that binds to H19. We confirmed that combining eIF4A3 with H19 obstructed the recruitment of eIF4A3 to the cell-cycle gene mRNA. Our results suggest that H19, as a growth regulator, could serve as a candidate prognostic biomarker and target for new therapies in human CRC.
DOI: 10.3390/genes9020092
2018
Cited 136 times
Identification of Key Pathways and Genes in the Dynamic Progression of HCC Based on WGCNA
Hepatocellular carcinoma (HCC) is a devastating disease worldwide. Though many efforts have been made to elucidate the process of HCC, its molecular mechanisms of development remain elusive due to its complexity. To explore the stepwise carcinogenic process from pre-neoplastic lesions to the end stage of HCC, we employed weighted gene co-expression network analysis (WGCNA) which has been proved to be an effective method in many diseases to detect co-expressed modules and hub genes using eight pathological stages including normal, cirrhosis without HCC, cirrhosis, low-grade dysplastic, high-grade dysplastic, very early and early, advanced HCC and very advanced HCC. Among the eight consecutive pathological stages, five representative modules are selected to perform canonical pathway enrichment and upstream regulator analysis by using ingenuity pathway analysis (IPA) software. We found that cell cycle related biological processes were activated at four neoplastic stages, and the degree of activation of the cell cycle corresponded to the deterioration degree of HCC. The orange and yellow modules enriched in energy metabolism, especially oxidative metabolism, and the expression value of the genes decreased only at four neoplastic stages. The brown module, enriched in protein ubiquitination and ephrin receptor signaling pathways, correlated mainly with the very early stage of HCC. The darkred module, enriched in hepatic fibrosis/hepatic stellate cell activation, correlated with the cirrhotic stage only. The high degree hub genes were identified based on the protein-protein interaction (PPI) network and were verified by Kaplan-Meier survival analysis. The novel five high degree hub genes signature that was identified in our study may shed light on future prognostic and therapeutic approaches. Our study brings a new perspective to the understanding of the key pathways and genes in the dynamic changes of HCC progression. These findings shed light on further investigations.
DOI: 10.1016/j.aquaculture.2023.740392
2024
Cited 5 times
Comparison of muscle nutritional composition, texture quality, carotenoid metabolites and transcriptome to underling muscle quality difference between wild-caught and pond-cultured Yellow River carp (Cyprinus carpio haematopterus)
The common carp is one of the most important freshwater aquaculture fish. The quality is an emerging concern for aquatic animals, and wild-caught fish is considered to exhibit better quality compared with cultured fish in some species. In present study, muscle nutritional composition, flesh quality index, scale and fins color, carotenoid metabolites, and RNA-sequencing were compared between wild-caught carp (WCC) and pond-cultured carp (PCC) to elucidate their quality difference. Results showed that WCC showed higher moisture, EPA, DHA, and EAA/TAA compared with PCC (P < 0.05). However, PCC showed higher muscle protein and lipid content, and mono-unsaturated fatty acids (MUFA). Hardness, chewiness, and shear force were significantly higher in WCC compared with PCC. The WCC showed higher a* and b*values in back and caudal fin (P < 0.05). Targeted metabolomics of carotenoids analysis showed that 4 carotenoid metabolites in scale and 6 carotenoid metabolites in fins showed significant difference between WCC and PCC. Furthermore, transcriptome analysis showed that a total of 8624 differentially expressed genes (DEGs) were identified in WCC vs. PCC. Gene function enrichment demonstrated that up-regulated DEGs were mainly in response to cell cycle, immunology regulation, and inositol phosphates metabolism, whereas, down-regulation genes were mainly in response in RNA transport, carbohydrate metabolism, protein and lipid metabolism. The study provided a comprehensive view of nutritional and texture difference between WCC and PCC, and which could provide reference for improving nutritional and texture quality in farmed carp.
DOI: 10.4049/jimmunol.160.11.5273
1998
Cited 293 times
Expression of Complement Receptors 1 and 2 on Follicular Dendritic Cells Is Necessary for the Generation of a Strong Antigen-Specific IgG Response
Two mechanisms could account for the impaired humoral immune response found in Cr2-/- mice. The absence of complement receptors 1 and 2 (CR1, CR2) on B cells could affect their activation. Alternatively, impaired Ag trapping by follicular dendritic cells (FDC) could affect B cell maturation into Ig-secreting or memory B cells. To compare the roles of CR1 and CR2 on B cells vs FDC in this abnormal response, bone marrow (BM) chimeric mice were generated and immunized with specific T-dependent Ags. The primary and secondary Ab response was measured. Cr2+/+ animals reconstituted with a Cr2-/- BM generated a diminished but detectable humoral immune response compared with controls. When injected with preformed immune complexes (IC), these mice maintained follicular IC localization. Cr2-/- animals reconstituted with a Cr2+/+ BM had an initial rise in the Ab titer, but were unable to maintain it as shown by a pronounced decrease in the IgG titer. This defect persisted during the secondary immune response. Follicular IC trapping was also impaired. Despite the abnormal Ab response, germinal center formation was retained in all of the chimeric animals. These experiments are the first to demonstrate an absolute requirement for CR1 and CR2 expression on FDC in the generation of a normal humoral immune response.
DOI: 10.1104/pp.112.196048
2012
Cited 153 times
Uncovering Small RNA-Mediated Responses to Cold Stress in a Wheat Thermosensitive Genic Male-Sterile Line by Deep Sequencing
The male sterility of thermosensitive genic male sterile (TGMS) lines of wheat (Triticum aestivum) is strictly controlled by temperature. The early phase of anther development is especially susceptible to cold stress. MicroRNAs (miRNAs) play an important role in plant development and in responses to environmental stress. In this study, deep sequencing of small RNA (smRNA) libraries obtained from spike tissues of the TGMS line under cold and control conditions identified a total of 78 unique miRNA sequences from 30 families and trans-acting small interfering RNAs (tasiRNAs) derived from two TAS3 genes. To identify smRNA targets in the wheat TGMS line, we applied the degradome sequencing method, which globally and directly identifies the remnants of smRNA-directed target cleavage. We identified 26 targets of 16 miRNA families and three targets of tasiRNAs. Comparing smRNA sequencing data sets and TaqMan quantitative polymerase chain reaction results, we identified six miRNAs and one tasiRNA (tasiRNA-ARF [for Auxin-Responsive Factor]) as cold stress-responsive smRNAs in spike tissues of the TGMS line. We also determined the expression profiles of target genes that encode transcription factors in response to cold stress. Interestingly, the expression of cold stress-responsive smRNAs integrated in the auxin-signaling pathway and their target genes was largely noncorrelated. We investigated the tissue-specific expression of smRNAs using a tissue microarray approach. Our data indicated that miR167 and tasiRNA-ARF play roles in regulating the auxin-signaling pathway and possibly in the developmental response to cold stress. These data provide evidence that smRNA regulatory pathways are linked with male sterility in the TGMS line during cold stress.
DOI: 10.1016/j.ultsonch.2014.10.027
2015
Cited 103 times
Anti-metastatic and pro-apoptotic effects elicited by combination photodynamic therapy with sonodynamic therapy on breast cancer both in vitro and in vivo
Sono-Photodynamic therapy (SPDT), a new modality for cancer treatment, is aimed at enhancing anticancer effects by the combination of sonodynamic therapy (SDT) and photodynamic therapy (PDT). In this study, we investigated the antitumor effect and possible mechanisms of Chlorin e6 (Ce6) mediated SPDT (Ce6-SPDT) on breast cancer both in vitro and in vivo. MTT assay revealed that the combined therapy markedly enhanced cell viability loss of breast cancer cell lines (MDA-MB-231, MCF-7 and 4T1) compared with SDT and PDT alone. Propidium iodide/hoechst33342 double staining reflected that 4T1 cells with apoptotic morphological characteristics were significantly increased in groups given combined therapy. Besides, the combined therapy caused obvious mitochondrial membrane potential (MMP) loss at early 1 h post SPDT treatment. The generation of intracellular reactive oxygen species (ROS) detected by flow cytometry was greatly increased in 4T1 cells treated with the combination therapy, and the loss of cell viability and MMP could be effectively rescued by pre-treatment with the ROS scavenger N-acetylcysteine (NAC). Further, Ce6-SPDT markedly inhibited the tumor growth (volume and weight) and lung metastasis in 4T1 tumor-bearing mice, but had no effect on the body weight. Hematoxylin and eosin staining revealed obvious tissue destruction with large spaces in the Ce6-SPDT groups, and TUNEL staining indicated tumor cell apoptosis after treatment. Immunohistochemistry analysis showed that the expression level of VEGF and MMP were significantly decreased in the combined groups. These results indicated that Ce6-mediated SPDT enhanced the antitumor efficacy on 4T1 cells compared with SDT and PDT alone, loss of MMP and generation of ROS might be involved. In addition, Ce6-mediated SPDT significantly inhibited tumor growth and metastasis in mouse breast cancer 4T1 xenograft model, in which MMP-9 and VEGF may play a crucial role.
DOI: 10.1002/adma.202000208
2020
Cited 95 times
Aptamer/Peptide‐Functionalized Genome‐Editing System for Effective Immune Restoration through Reversal of PD‐L1‐Mediated Cancer Immunosuppression
Abstract Effective reversal of tumor immunosuppression is of critical importance in cancer therapy. A multifunctional delivery vector that can effectively deliver CRISPR‐Cas9 plasmid for β‐catenin knockout to reverse tumor immunosuppression is constructed. The multi‐functionalized delivery vector is decorated with aptamer‐conjugated hyaluronic acid and peptide‐conjugated hyaluronic acid to combine the tumor cell/nuclear targeting function of AS1411 with the cell penetrating/nuclear translocation function of TAT‐NLS. Due to the significantly enhanced plasmid enrichment in malignant cell nuclei, the genome editing system can induce effective β‐catenin knockout and suppress Wnt/β‐catenin pathway, resulting in notably downregulated proteins involved in tumor progression and immunosuppression. Programmed death‐ligand 1 (PD‐L1) downregulation in edited tumor cells not only releases the PD‐1/PD‐L1 brake to improve the cancer killing capability of CD8 + T cells, but also enhances antitumor immune responses of immune cells. This provides a facile strategy to reverse tumor immunosuppression and to restore immunosurveillance and activate anti‐tumor immunity.
DOI: 10.1186/s12864-016-3476-6
2017
Cited 78 times
Comprehensive CircRNA expression profile and selection of key CircRNAs during priming phase of rat liver regeneration
Rat liver regeneration (LR) proceeds along a process of highly organized and ordered tissue growth in response to the loss or injury of liver tissue, during which many physiological processes may play important roles. The molecular mechanism of hepatocyte proliferation, energy metabolism and substance metabolism during rat LR had been elucidated. Further, the correlation of circular RNA (circRNA) abundance with proliferation has recently been clarified. However, the regulatory capacity of circRNA in rat LR remains a fascinating topic.To investigate the regulatory mechanism of circRNA during priming phase of rat LR, high-throughput RNA sequencing technology was performed to unbiasedly profile the expression of circRNA during priming phase of rat LR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) biological pathway analysis was conducted to predict the functions of differentially expressed circRNAs and their host linear transcripts. Co-expression networks of circRNA-miRNA were constructed based on the correlation analysis between the differentially expressed LR-related circRNAs and the condition of their miRNA binding sites. To excavate the key circRNAs in the early phase of rat LR, we comprehensively evaluated and integrated the relationship of expression level between the circRNAs and the linear transcripts as well as the distribution of miRNA binding sites in circRNA sequences.This paper is the first to employ the comprehensive circRNA expression profile and to investigate circRNA-miRNA interactions during priming phase of rat LR. Two thousand four hundred twelve circRNAs were detected, and 159 circRNAs deriving from 116 host linear transcripts differentially expressed (p < 0.05). Six significantly changed circRNAs during priming phase of rat LR were screened as key circle molecules, and then were validated by qRT-PCR. This study will lay the foundation for revealing the functional roles of circRNAs during rat LR and help solve the remaining clinical problems.
DOI: 10.1002/hep.32332
2022
Cited 37 times
Notch‐triggered maladaptation of liver sinusoidal endothelium aggravates nonalcoholic steatohepatitis through endothelial nitric oxide synthase
Although NASH can lead to severe clinical consequences, including cirrhosis and hepatocellular carcinoma, no effective treatment is currently available for this disease. Increasing evidence indicates that LSECs play a critical role in NASH pathogenesis; however, the mechanisms involved in LSEC-mediated NASH remain to be fully elucidated.In the current study, we found that LSEC homeostasis was disrupted and LSEC-specific gene profiles were altered in methionine-choline-deficient (MCD) diet-induced NASH mouse models. Importantly, Notch signaling was found to be activated in LSECs of NASH mice. To then investigate the role of endothelial Notch in NASH progression, we generated mouse lines with endothelial-specific Notch intracellular domain (NICD) overexpression or RBP-J knockout to respectively activate or inhibit Notch signaling in endothelial cells. Notably, endothelial-specific overexpression of the NICD accelerated LSEC maladaptation and aggravated NASH, whereas endothelial cell-specific inhibition of Notch signaling restored LSEC homeostasis and improved NASH phenotypes. Furthermore, we demonstrated that endothelial-specific Notch activation exacerbated NASH by inhibiting endothelial nitric oxide synthase (eNOS) transcription, whereas administration of the pharmacological eNOS activator YC-1 alleviated hepatic steatosis and lipid accumulation resulting from Notch activation. Finally, to explore the therapeutic potential of using Notch inhibitors in NASH treatment, we applied two gamma-secretase inhibitors-DAPT and LY3039478-in an MCD diet-induced mouse model of NASH, and found that both inhibitors effectively ameliorated hepatic steatosis, inflammation, and liver fibrosis.Endothelial-specific Notch activation triggered LSEC maladaptation and exacerbated NASH phenotypes in an eNOS-dependent manner. Genetic and pharmacological inhibition of Notch signaling effectively restored LSEC homeostasis and ameliorated NASH progression.
DOI: 10.1016/j.esr.2022.100911
2022
Cited 36 times
Impacts of industrial structure adjustment, upgrade and coordination on energy efficiency: Empirical research based on the extended STIRPAT model
This paper first estimates the energy efficiency of 13 cities and 30 key industries in the Beijing-Tianjin-Hebei (BTH) region between 2008 and 2017 using the super-efficiency slacks-based measure (SBM) model. Structural deviation, Moore index, and coupling coordination degree quantify the cities' industrial restructuring, upgrading, and coordination. Afterward, the extended STIRPAT model reveals the relationship between energy efficiency and industrial structure. Finally, a coupling coordination degree model measures the coupling between energy efficiency and industrial advanced development coefficients in key industries. The results show a wide variation in energy efficiency between cities, with most cities experiencing a decline in energy efficiency. Industrial structure adjustment and upgrading are on the rise, and coordination is on the wane, with the most significant changes occurring in the cities around Beijing. In most cities, industrial structure adjustment, upgrading, and coordination on energy efficiency are negative, positive, and negative. The coupling imbalance of energy efficiency and industrial advanced development coefficients is the most apparent feature of the key sectors, and this feature is not improving.
DOI: 10.1080/19490976.2021.2013764
2022
Cited 34 times
Microbial hydrogen economy alleviates colitis by reprogramming colonocyte metabolism and reinforcing intestinal barrier
With the rapid development and high therapeutic efficiency and biosafety of gas-involving theranostics, hydrogen medicine has been particularly outstanding because hydrogen gas (H2), a microbial-derived gas, has potent anti-oxidative, anti-apoptotic, and anti-inflammatory activities in many disease models. Studies have suggested that H2-enriched saline/water alleviates colitis in murine models; however, the underlying mechanism remains poorly understood. Despite evidence demonstrating the importance of the microbial hydrogen economy, which reflects the balance between H2-producing (hydrogenogenic) and H2-utilizing (hydrogenotrophic) microbes in maintaining colonic mucosal ecosystems, minimal efforts have been exerted to manipulate relevant H2-microbe interactions for colonic health. Consistent with previous studies, we found that administration of hydrogen-rich saline (HS) ameliorated dextran sulfate sodium-induced acute colitis in a mouse model. Furthermore, we demonstrated that HS administration can increase the abundance of intestinal-specific short-chain fatty acid (SCFA)-producing bacteria and SCFA production, thereby activating the intracellular butyrate sensor peroxisome proliferator-activated receptor γ signaling and decreasing the epithelial expression of Nos2, consequently promoting the recovery of the colonic anaerobic environment. Our results also indicated that HS administration ameliorated disrupted intestinal barrier functions by modulating specific mucosa-associated mucolytic bacteria, leading to substantial inhibition of opportunistic pathogenic Escherichia coli expansion as well as a significant increase in the expression of interepithelial tight junction proteins and a decrease in intestinal barrier permeability in mice with colitis. Exogenous H2 reprograms colonocyte metabolism by regulating the H2-gut microbiota-SCFAs axis and strengthens the intestinal barrier by modulating specific mucosa-associated mucolytic bacteria, wherein improved microbial hydrogen economy alleviates colitis.
DOI: 10.1002/anie.202208757
2022
Cited 34 times
Chiral Nanozymes for Enantioselective Biological Catalysis
As a neat combination of the characteristics of enzymatic activity and nanomaterials, nanozymes have attracted much attention. Although tremendous effort has been devoted to developing nanozymes with high catalytic activity, substrate selectivity is often overlooked in the construction of nanozymes. With their subtly evolving structures, natural enzymes generally possess high selectivity for chiral substrates which play important roles in biosynthesis and biomedical applications. However, the rational construction of nanozymes with high enantioselectivity remains a significant challenge. In this Minireview, we provide an overview of recent advances in strategies for the synthesis of chiral nanozymes and their enantioselective biological catalysis. We further focus on current challenges, potential solutions, and future developing trends of chiral nanozyme-based enantioselective biological catalysis. There is plenty of room to explore. This Minireview will provide new insights into the development of chiral nanozymes and their applications.
DOI: 10.1016/j.xinn.2022.100235
2022
Cited 28 times
Can the “10-year fishing ban” rescue biodiversity of the Yangtze River?
Rivers and their lakes are among the world’s most important ecosystems supporting high biodiversity and providing various services through connections with vast landscapes. Reconciling exploitation with sustainability remains one of the world’s greatest challenges to maintain and/or recover the health of river ecosystems and hence their biodiversity and ecosystem services.1 As one of the major national initiatives toward building “ecological civilization” and an extensive protection of the Yangtze River in China, a “10-year fishing ban” plan (TYFB) was launched from January 2021.
DOI: 10.1146/annurev-biodatasci-020722-120642
2023
Cited 14 times
Decoding Aging Hallmarks at the Single-Cell Level
Organismal aging exhibits wide-ranging hallmarks in divergent cell types across tissues, organs, and systems. The advancement of single-cell technologies and generation of rich datasets have afforded the scientific community the opportunity to decode these hallmarks of aging at an unprecedented scope and resolution. In this review, we describe the technological advancements and bioinformatic methodologies enabling data interpretation at the cellular level. Then, we outline the application of such technologies for decoding aging hallmarks and potential intervention targets and summarize common themes and context-specific molecular features in representative organ systems across the body. Finally, we provide a brief summary of available databases relevant for aging research and present an outlook on the opportunities in this emerging field.
DOI: 10.1016/j.jhazmat.2023.132640
2024
Cited 4 times
Identification and analysis of microplastics in human lower limb joints
Microplastics (MPs) have been detected in various human tissues, including the liver, placenta, and blood. However, studies about MPs in the human locomotor system are limited. This study evaluated the presence of MPs in the synovium of 45 patients undergoing hip or knee arthroplasty using micro-Fourier transform infrared spectroscopy, scanning electron microscopy, and Raman microscopy and investigated their association with clinical indicators and local cellular responses. A total of 343 MPs of nine common types were identified, with a mean abundance of 5.24 ± 2.07 particles/g and ranging from 1.16 to 10.77 particles/g. Although there was no clear correlation between MP abundance and demographics, MP abundance was higher in hip samples than in knee samples. In addition, a potential association was observed between MP abundance and specific clinical diagnoses. Transcriptomic analysis revealed that a three-fold increase in MP abundance corresponded to enhanced local cellular stress responses, particularly heat shock protein reactions. Our findings demonstrate the presence of MPs in human joints and suggest that further studies are needed to explore the intricate associations between MPs and anatomical location, clinical diagnosis, and local cellular responses.
DOI: 10.1046/j.1432-1033.2003.03645.x
2003
Cited 136 times
Calcium and polyamine regulated calcium‐sensing receptors in cardiac tissues
Activation of a calcium-sensing receptor (Ca-SR) leads to increased intracellular calcium concentration and altered cellular activities. The expression of Ca-SR has been identified in both nonexcitable and excitable cells, including neurons and smooth muscle cells. Whether Ca-SR was expressed and functioning in cardiac myocytes remained unclear. In the present study, the transcripts of Ca-SR were identified in rat heart tissues using RT-PCR that was further confirmed by sequence analysis. Ca-SR proteins were detected in rat ventricular and atrial tissues as well as in isolated cardiac myocytes. Anti-(Ca-SR) Ig did not detect any specific bands after preadsorption with standard Ca-SR antigens. An immunohistochemistry study revealed the presence of Ca-SR in rat cardiac as well as other tissues. An increase in extracellular calcium or gadolinium induced a concentration-dependent sustained increase in [Ca2+]i in isolated ventricular myocytes from adult rats. Spermine (1-10 mm) also increased [Ca2+]i. Pre-treatment of cardiac myocytes with thapsigargin or U73122 abolished the extracellular calcium, gadolinium or spermine-induced increase in [Ca2+]i. The blockade of Na+/Ca2+ exchanger or voltage-dependent calcium channels did not alter the extracellular calcium-induced increase in [Ca2+]i. Finally, extracellular calcium, gadolinium and spermine all increased intracellular inositol 1,4,5-triphosphate (IP3) levels. Our results demonstrated that Ca-SR was expressed in cardiac tissue and cardiomyocytes and its function was regulated by extracellular calcium and spermine.
DOI: 10.1016/j.foodchem.2010.04.029
2010
Cited 97 times
Effects of pulsed electric field treatment on a bovine serum albumin–dextran model system, a means of promoting the Maillard reaction
Effects of pulsed electric field treatment on browning intensity, antioxidant activity, protein patterns and chemical structure of the bovine serum albumin–dextran copolymer were investigated. Results showed Maillard reaction between bovine serum albumin and dextran was significantly accelerated when the electric field intensity was higher than 10 kV/cm, which was proved by changes in A294, browning, antioxidant activity and electrophoresis tests. At the same time, pronounced changes of chemical structure were found by circular dichroism test. The α-helix, β-sheet, β-turns and random coil were changed from approximately 42.6%, 1.9%, 17.5% and 33.9% to 14.5%, 33.0%, 21.2% and 30.2%, respectively, after treatment at 20 kV/cm for 7.35 ms. All data indicated that pulsed electric field was a means to promote Maillard-based copolymerisation.
DOI: 10.7863/jum.2010.29.1.61
2010
Cited 92 times
Antitumor Effect of Docetaxel-Loaded Lipid Microbubbles Combined With Ultrasound-Targeted Microbubble Activation on VX2 Rabbit Liver Tumors
Objective. The purpose of the study was to explore the antitumor effect of docetaxel-loaded lipid microbubbles combined with ultrasound-targeted microbubble activation (UTMA) on VX2 rabbit liver tumors. Methods. Docetaxel-loaded lipid microbubbles were made by a mechanical vibration technique. VX2 liver tumor models were established in 90 rabbits, which were randomly divided into 6 groups, including control, docetaxal-loaded lipid microbubbles alone, docetaxal alone, docetaxal combined with ultrasound, pure lipid microbubbles combined with ultrasound, and docetaxel-loaded lipid microbubbles combined with ultrasound (DOC+MB/US). The tumor volume and inhibition rate (IR) of tumor growth were calculated and compared. Apoptosis was detected by terminal deoxyuridine nick end labeling. Proliferating cell nuclear antigen and matrix metalloproteinase 2 (MMP2) protein expression was detected by immunohistochemistry. Caspase 3 and MMP2 messenger RNA (mRNA) expression was detected by in situ hybridization histochemistry. The tumor metastasis rate and survival time of the animals were compared. Results. The IR and apoptotic index of the DOC+MB/US group were the highest among all groups, and the proliferating labeling index was the lowest. Matrix metalloproteinase 2 protein and mRNA expression in the DOC+MB/US group was the lowest among all groups, and caspase 3 mRNA expression in the DOC+MB/US group was the highest. The extensive metastasis rate in the DOC+MB/US group was the lowest, and the survival time of the animals in the DOC+MB/US group was the longest. Conclusions. Docetaxel-loaded lipid microbubbles combined with UTMA could inhibit the growth of VX2 rabbit liver tumors by deferring proliferation and promoting apoptosis, which may provide a novel targeted strategy for chemotherapy of liver carcinoma.
DOI: 10.1016/j.yjmcc.2011.12.004
2012
Cited 71 times
Increased neointimal formation in cystathionine gamma-lyase deficient mice: Role of hydrogen sulfide in α5β1-integrin and matrix metalloproteinase-2 expression in smooth muscle cells
The physiological and pathological roles of hydrogen sulfide (H(2)S) in the regulation of cardiovacular functions have been recognized. Vascular smooth muscle cells (SMCs) express cystathionine gamma-lyase (CSE) and produce significant amount of H(2)S. Although growing evidence demonstated the anti-atherosclerotic effect of H(2)S, less is known about the contribution of the endogenous CSE/H(2)S pathway to the development of vascular remodeling. This study investigated the roles of the CSE/H(2)S pathway on SMC migration and neoimtimal formation by using CSE knockout (KO) mice. SMCs and aortic explants isolated from CSE KO mice exhibited more migration and outgrowth compared with that from wild-type (WT) mice, and exogenously applied NaHS (a H(2)S donor) at 100 μM significantly inhibited SMC migration and outgrowth. SMCs became more elongated and spread in the absence of CSE, and fibronectin significantly stimulated adhesion and migration of SMCs from CSE KO mice (KO-SMCs) in comparison with SMCs from WT mice (WT-SMCs). The expressions of α5- and β1-integrins were significantly higher in KO-SMCs, and functional blocking of α5β1-integrin effectively abrogated KO-SMC migration. CSE deficiency also enhanced matrix metalloproteinase-2 (MMP-2) expression, and the selective blocking of MMP-2 decreased KO-SMC migration. NaHS treatment decreased both the expressions of α5- and β1-integrins and MMP-2. We further found that the expressions of α5- and β1-integrins as well as MMP-2, were stimulated by fibronectin, and that the blockage of α5β1-integrin reduced but overexpression of α5β1-integrin induced MMP-2 expression in both WT-SMCs and KO-SMCs. We also noticed that CSE deficiency in mice led to increased neointima formation in carotid arteries 4 weeks after ligation, which were attenuated by NaHS administration. In conclusion, inhibition of SMC migration by H(2)S may be a novel target for the treatment of vascular occlusive disorder.
DOI: 10.1186/s13578-016-0099-1
2016
Cited 69 times
Hydrogen sulfide decreases high glucose/palmitate-induced autophagy in endothelial cells by the Nrf2-ROS-AMPK signaling pathway
Excessive autophagy induced by extravagant oxidative stress is the main reason for diabetes-induced vascular endothelial cells dysfunction. Hydrogen sulfide (H2S) has anti-oxidative effects but its regulation on excessive autophagy of vascular endothelial cells is unclear. In this study, aorta of db/db mice (28 weeks old) and rat aortic endothelial cells (RAECs) treated with 40 mM glucose and 500 μM palmitate acted as type II diabetic animal and cellular models, respectively, and 100 μMNaHS was used as an exogenous H2S donor. The apoptosis level was measured by terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) staining and Hoechst 33342/PI staining. The activities of SOD, CAT and respiratory complexes were also measured. The mRNA levels of SOD and CAT were detected by real-time PCR. AMPK-siRNA was used to detect the effect of AMPK on autophagy. Western blotting was used to detected the protein level. H2S production was decreased (p < 0.05, p < 0.01) both in vitro and in vivo; NaHS treatment rescued this impairment (p < 0.05, p < 0.01). The expression of adhesive proteins was increased (p < 0.05, p < 0.01) both in vitro and in vivo; NaHS attenuated (p < 0.05, p < 0.01) these alterations. NaHS could protect endothelial cells against apoptosis induced by type II diabetes (p < 0.05, p < 0.01). Furthermore, the expressions and activities of SOD and CAT were impaired (p < 0.05, p < 0.01) in endothelial cells of diabetes II; NaHS treatment attenuated (p < 0.05) this impairment. NaHS also increased ATP production (p < 0.05) and activities of respiratory complexes (p < 0.05), and the ratio of p-AMPK to AMPK was also decreased by NaHS (p < 0.01). The level of autophagy in endothelial cells was also decreased (p < 0.05, p < 0.01) by NaHS treatment and AMPK-siRNA treatment. The expression of Nrf2 in the nuclei was increased (p < 0.05) by NaHS treatment. Exogenous H2S might protect arterial endothelial cells by suppressing excessive autophagy induced by oxidative stress through the Nrf2-ROS-AMPK signaling pathway.
DOI: 10.1016/j.ijcard.2016.06.200
2016
Cited 67 times
Involvement of exogenous H2S in recovery of cardioprotection from ischemic post-conditioning via increase of autophagy in the aged hearts
Background Hydrogen sulfide (H2S), which is a member of the gasotransmitter family, plays an important physiological and pathological role in cardiovascular system. Ischemic post-conditioning (PC) provides myocardial protective effect in the young hearts but not in the aged hearts. Exogenous H2S restores PC-induced cardioprotection by inhibition of mitochondrial permeability transition pore (mPTP) in the aged hearts. However, whether H2S contributes to the recovery of PC-induced cardioprotection via up-regulation of autophagy in the aged hearts is unclear. Methods The isolated aged rat hearts (24-months-old, 450–500 g) and aged cardiomyocytes-induced by d-galactose were exposed to an ischemia/reperfusion (I/R) and PC protocol. Results We found PC lost cardioprotection in the aged hearts and cardiomyocytes. NaHS (a H2S donor) significantly restored cardioprotection of PC through decreasing myocardial damage, infarct size, and apoptosis, improving cardiac function, increasing cell viability and autophagy in the aged hearts and cardiomyocytes. 3-MA (an autophagy inhibitor) abolished beneficial effect of NaHS in the aged hearts. In addition, in the aged cardiomyocytes, NaHS up-regulated AMPK/mTOR pathway, and the effect of NaHS on PC was similar to the overexpression of Atg 5, treatment of AICAR (an AMPK activator) or Rapamycin (a mTOR inhibitor, an autophagy activator), respectively. Conclusions These results suggest that exogenous H2S restores cardioprotection from PC by up-regulation of autophagy via activation of AMPK/mTOR pathway in the aged hearts and cardiomyocytes.
DOI: 10.1126/sciimmunol.aau6598
2018
Cited 67 times
Intrinsic properties of human germinal center B cells set antigen affinity thresholds
Protective antibody responses to vaccination or infection depend on affinity maturation, a process by which high-affinity germinal center (GC) B cells are selected on the basis of their ability to bind, gather, and present antigen to T follicular helper (Tfh) cells. Here, we show that human GC B cells have intrinsically higher-affinity thresholds for both B cell antigen receptor (BCR) signaling and antigen gathering as compared with naïve B cells and that these functions are mediated by distinct cellular structures and pathways that ultimately lead to antigen affinity- and Tfh cell-dependent differentiation to plasma cells. GC B cells bound antigen through highly dynamic, actin- and ezrin-rich pod-like structures that concentrated BCRs. The behavior of these structures was dictated by the intrinsic antigen affinity thresholds of GC B cells. Low-affinity antigens triggered continuous engagement and disengagement of membrane-associated antigens, whereas high-affinity antigens induced stable synapse formation. The pod-like structures also mediated affinity-dependent antigen internalization by unconventional pathways distinct from those of naïve B cells. Thus, intrinsic properties of human GC B cells set thresholds for affinity selection.
DOI: 10.1016/j.colsurfb.2018.07.008
2018
Cited 57 times
Aptamer-functionalized albumin-based nanoparticles for targeted drug delivery
Proteins have been extensively explored as versatile nanocarriers for drug delivery due to their complete biocompatibility, ease of surface modification, and lack of toxicity and immunogenicity. In this study, a facile strategy was used to construct aptamer-functionalized albumin-based nanoparticles for effective drug delivery and targeted cancer therapy. A hydrophobic drug, doxorubicin (DOX) was employed to trigger the self-assembly of bovine serum albumin (BSA) to from stable nanoparticles via hydrophobic interaction, and then a tumor targeting aptamer AS1411 was incorporated to the surface of DOX loaded BSA. Due to the specific recognition between AS1411 and its receptor over-expressed on tumor cells, the aptamer-modified nanoparticles show higher cellular uptake and stronger cell inhibitory efficacy against cancerous MCF-7 cells as compared with the nanoparticles without aptamer modification. In addition, DOX loaded aptamer-functionalized nanoparticles can induce more significant down-regulation of Bcl-2 and PCNA as well as up-regulation of pRB, PARP and Bax in MCF-7 cells compared with unmodified nanoparticles, indicating the aptamer modification can induce cell apoptosis more effectively. Besides, aptamer-modified nanoparticles exhibit a significantly improved capability in up-regulating p16, p21 and E-cadherin, and down-regulating EpCAM, vimentin, Snail, MMP-9, CD44 and CD133, implying the favorable effects of drug delivery on the prevention of tumor progression and metastasis.
DOI: 10.1039/c8nr05294h
2018
Cited 53 times
A multi-functional macrophage and tumor targeting gene delivery system for the regulation of macrophage polarity and reversal of cancer immunoresistance
A macrophage and tumor targeting delivery system of pDNA IL-12 can effectively regulate macrophage polarity and reverse cancer immunoresistance.
DOI: 10.1021/acs.biomac.8b00511
2018
Cited 52 times
A Dual-Targeting Delivery System for Effective Genome Editing and In Situ Detecting Related Protein Expression in Edited Cells
One of critical steps in genome editing by CRISPR-Cas9 is to deliver the CRISPR-Cas9 system into targeted cells. In this study, we developed a dual-targeting delivery system based on polymer/inorganic hybrid nanoparticles to realize highly efficient genome editing in targeted tumor cells as well as in situ detection on the related protein expression in edited cells. The CRISPR-Cas9 plasmid for CDK11 knockout was encapsulated in the core of the delivery system composed of protamine sulfate, calcium carbonate, and calcium phosphate by coprecipitation, and functional derivatives of carboxymethyl chitosan (biotinylated carboxymethyl chitosan with biotin ligands and aptamer-incorporated carboxymethyl chitosan with AS1411 ligands) were decorated on the nanovector surface by electrostatic interactions to form the dual-targeting delivery system. On the basis of the tumor cell targeting capability of biotin and AS1411 ligands as well as the nuclear targeting of AS1411, the dual-targeting system can deliver the CRISPR-Cas9 plasmid into the nuclei of tumor cells to realize highly efficient genome editing, resulting in a dramatic decrease (>90%) in CDK11 protein together with the significant downregulation of other proteins involved in tumor development, including an ∼90% decrease in MMP-9, >40% decrease in VEGF, and ∼70% decrease in survivin. Using the same vector, molecular beacons can be easily delivered to edited cell nuclei to in situ detect the mRNA level of related proteins (p53 and survivin as typical examples) and mRNA distribution in subcellular organelles. Our strategy can realize effective genome editing and in situ detection on related protein expression simultaneously.
DOI: 10.1021/acsami.9b11263
2019
Cited 52 times
Multifunctional Albumin-Based Delivery System Generated by Programmed Assembly for Tumor-Targeted Multimodal Therapy and Imaging
To enhance the treatment efficiency in tumor therapy, we developed a tumor-targeting protein-based delivery system, DOX&ICG@BSA-KALA/Apt, to efficiently integrate multimodal therapy with tumor imaging and realize synchronous photodynamic therapy/photothermal therapy/chemotherapy. In the delivery system, a chemotherapeutic drug (doxorubicin, DOX) and an optotheranostic agent (indocyanine green, ICG) were co-loaded in bovine serum albumin (BSA) via a hydrophobic-interaction-induced self-assembly to form stable DOX&ICG@BSA nanoparticles. After the decoration of a surface layer composed of a tumor-targeting aptamer (AS1411) and a cell-penetrating peptide (KALA), the obtained DOX&ICG@BSA-KALA/Apt nanoparticles exhibit a significantly improved multimodal cancer therapeutic efficiency due to the enhanced cancer cellular uptake mediated by AS1411 and KALA. In vitro and in vivo studies show that the multimodal theranostic system can efficiently inhibit tumor growth. In addition, the near-infrared fluorescent/photothermal dual-mode imaging enables accurate visualization of the therapeutic action in tumor sites. This study provides a facile strategy to construct self-assembled multimodal theranostic systems, and the functional protein-based theranostic system prepared holds great promise in multimodal cancer therapeutics.
DOI: 10.1073/pnas.1716300115
2018
Cited 51 times
Large-scale comparative epigenomics reveals hierarchical regulation of non-CG methylation in <i>Arabidopsis</i>
Genome-wide characterization by next-generation sequencing has greatly improved our understanding of the landscape of epigenetic modifications. Since 2008, whole-genome bisulfite sequencing (WGBS) has become the gold standard for DNA methylation analysis, and a tremendous amount of WGBS data has been generated by the research community. However, the systematic comparison of DNA methylation profiles to identify regulatory mechanisms has yet to be fully explored. Here we reprocessed the raw data of over 500 publicly available Arabidopsis WGBS libraries from various mutant backgrounds, tissue types, and stress treatments and also filtered them based on sequencing depth and efficiency of bisulfite conversion. This enabled us to identify high-confidence differentially methylated regions (hcDMRs) by comparing each test library to over 50 high-quality wild-type controls. We developed statistical and quantitative measurements to analyze the overlapping of DMRs and to cluster libraries based on their effect on DNA methylation. In addition to confirming existing relationships, we revealed unanticipated connections between well-known genes. For instance, MET1 and CMT3 were found to be required for the maintenance of asymmetric CHH methylation at nonoverlapping regions of CMT2 targeted heterochromatin. Our comparative methylome approach has established a framework for extracting biological insights via large-scale comparison of methylomes and can also be adopted for other genomics datasets.
DOI: 10.1016/j.bbrc.2018.02.102
2018
Cited 51 times
Inhibition of HMGB1 mediates neuroprotection of traumatic brain injury by modulating the microglia/macrophage polarization
Microglia/Macrophages have a double-edged role in secondary brain damage after traumatic brain injury (TBI) depending on polarization toward proinflammatory M1 or anti-inflammatory M2 phenotypes. Recently, high-mobility group box 1 (HMGB1) was found to influence the polarization of macrophages. In this study, glycyrrhizin (GL), an inhibitor of HMGB1, was used to investigate whether the inhibition of HMGB1 could modulate microglia/macrophage polarization after TBI. The results showed that treatment with GL improved the neurological function recovery, reduced the lesion volume, and inhibited the release and expression of HMGB1 after TBI. In addition, the administration of GL suppressed M1 phenotype activation and promoted M2 phenotype activation of microglia/macrophages. In conclusion, the results suggested that GL attenuated TBI by inhibiting M1 phenotype while inducing M2 phenotype activation of microglia/macrophages, at least partly through inhibiting HMGB1. Also, targeting HMGB1 to modulate the microglia/macrophage polarization should be one potential therapeutic approach for TBI.
DOI: 10.2147/ndt.s212328
2019
Cited 48 times
&lt;p&gt;Comparative diagnostic accuracy of ACE-III and MoCA for detecting mild cognitive impairment&lt;/p&gt;
The aim of this study was to validate the reliability of the Chinese version of Addenbrooke's Cognitive Examination III (ACE-III) for detecting mild cognitive impairment. Furthermore, the present study compares the diagnostic accuracy of ACE-III with that of Montreal Cognitive Assessment (MoCA).One hundred and twenty patients with MCI and 136 healthy controls were included in the study. All patients were evaluated by the Chinese version of ACE-III, MoCA and MMSE.Subjects in the control group showed better performance in ACE-III total score and its subdomain scores than those in the MCI group. There was a significantly positive correlation between ACE-III total score and MoCA score. Meanwhile, there was also a significantly positive correlation between ACE-III total score and MMSE score. For ACE-III total score, a cut-off point of 85 yielded a sensitivity of 97.3% and a specificity of 90.7%. The AUC for ACE-III total score was 0.978. For MoCA, a cut-off point of 23 yielded a sensitivity of 86.5% and a specificity of 97.7%. The AUC for MoCA was 0.961. There were no significant differences in diagnostic accuracy between ACE-III and MoCA.The present findings support that both ACE-III and MoCA are useful for detecting MCI in early stages.
DOI: 10.1016/j.redox.2020.101514
2020
Cited 39 times
Exogenous spermine attenuates rat diabetic cardiomyopathy via suppressing ROS-p53 mediated downregulation of calcium-sensitive receptor
Diabetic cardiomyopathy (DCM) is a severe complication of type 1 diabetic (T1D) patients, manifested as combined diastolic and systolic dysfunction. DCM is associated with impaired calcium homeostasis secondary to decreased calcium-sensitive receptor (CaSR) expression. Spermine, a direct agonist of CaSR, was found deficient in cardiomyocytes of T1D rats. However, the role of spermine in DCM was unclear. Here, we examined the cardioprotective effect of exogenous spermine on DCM in streptozotocin (STZ) induced-T1D rats and high-glucose (HG)-incubated neonatal rat cardiomyocytes. Exogenous spermine significantly attenuated cardiac dysfunction in T1D rats, characterized by improved echocardiography, less fibrosis, reduced myocardial endoplasmic reticulum (ER) stress and oxidative stress, and increased expression of myocardial membrane CaSR. In cultured neonatal rat cardiomyocytes, exogenous spermine attenuated myocardial injury induced by HG treatment, demonstrated by restored cellular glucose uptake capacity, reduced expression of apoptotic markers, lowered level of oxidative stress, ER stress and unfolded protein response, and upregulated cell membrane CaSR. Mechanistically, the cardioprotective effect of spermine appeared dependent upon effective elimination of reactive oxygen species (ROS) and up-regulation of CaSR expression by suppressing the Nrf2-ROS-p53-MuRF1 axis. Taken together, these results suggest that exogenous spermine protects against DCM in vivo and in vitro, partially via suppressing ROS and p53-mediated downregulation of cell membrane CaSR.
DOI: 10.1021/acs.jmedchem.0c00280
2020
Cited 39 times
Pyridine-Embedded Phenothiazinium Dyes as Lysosome-Targeted Photosensitizers for Highly Efficient Photodynamic Antitumor Therapy
Development of new photosensitizers (PSs) with high photodynamic efficacy and minimal side effects is of great interest in photodynamic therapy (PDT). In this work, we reported several pyridine-embedded phenothiazinium (pyridophenothiazinium) dyes, which could be conveniently synthesized in a few short steps and acted as highly efficient and potent PSs to selectively localize to lysosomes and photosensitively kill cancer cells. Among them, compound 5, which possessed the ability of promoting intracellular reactive oxygen species (ROS) upon light irradiation by almost 40-fold higher than that of methylene blue (MB, a general phenothiazinium-based PS), exhibited a remarkable phototherapeutic index (PI = 53.8) against HT29 cancer cells, leading to eradication of large solid tumors (∼300 mm3) in a xenograft mouse model without apparent side effects. These results suggest that the pyridophenothiazinium dyes developed herein, especially compound 5, may serve as promising lysosome-targeted PSs for efficient photodynamic antitumor therapy.
DOI: 10.1016/j.jcmgh.2022.01.019
2022
Cited 20 times
Notch-Regulated c-Kit–Positive Liver Sinusoidal Endothelial Cells Contribute to Liver Zonation and Regeneration
Liver sinusoidal endothelial cells (SECs) promote the proliferation of hepatocytes during liver regeneration. However, the specific subset of SECs and its mechanisms during the process remain unclear. In this study, we investigated the potential role of c-kit+ SECs, a newly identified subset of SECs in liver regeneration.Partial hepatectomy mice models were established to induce liver regeneration. Hepatic c-kit expression was detected by quantitative reverse-transcription polymerase chain reaction, immunofluorescent staining, and fluorescence-activated cell sorting. VE-cadherin-cyclization recombinase-estrogen receptor (Cdh5-Cre-ERT) Notch intracellular domain and Cdh5-Cre recombination signal binding protein Jκfloxp mice were introduced to mutate Notch signaling. c-Kit+ SECs were isolated by magnetic beads. Single-cell RNA sequencing was performed on isolated SECs. Liver injuries were induced by CCl4 or quantitative polymerase chain reaction injection.Hepatic c-kit is expressed predominantly in SECs. Liver resident SECs contribute to the increase of c-kit during partial hepatectomy-induced liver regeneration. Isolated c-kit+ SECs promote hepatocyte proliferation in vivo and in vitro by facilitating angiocrine. The distribution of c-kit shows distinct spatial differences that are highly coincident with the liver zonation marker wingless-type MMTV integration site family, member2 (Wnt2). Notch mutation reshapes the c-kit distribution and liver zonation, resulting in altered hepatocyte proliferation. c-Kit+ SECs were shown to regulate hepatocyte regeneration through angiocrine in a Wnt2-dependent manner. Activation of the Notch signaling pathway weakens liver regeneration by inhibiting positive regulatory effects of c-kit+ SECs on hepatocytes. Furthermore, c-kit+ SEC infusion attenuates toxin-induced liver injuries in mice.Our results suggest that c-kit+ SECs contributes to liver zonation and regeneration through Wnt2 and is regulated by Notch signaling, providing opportunities for novel therapeutic approaches to liver injury in the future. Transcript profiling: GEO (accession number: GSE134037).
DOI: 10.1016/j.biocon.2023.109905
2023
Cited 7 times
Detecting wildlife trafficking in images from online platforms: A test case using deep learning with pangolin images
E-commerce has become a booming market for wildlife trafficking, as online platforms are increasingly more accessible and easier to navigate by sellers, while still lacking adequate supervision. Artificial intelligence models, and specifically deep learning, have been emerging as promising tools for the automated analysis and monitoring of digital online content pertaining to wildlife trade. Here, we used and fine-tuned freely available artificial intelligence models (i.e., convolutional neural networks) to understand the potential of these models to identify instances of wildlife trade. We specifically focused on pangolin species, which are among the most trafficked mammals globally and receiving increasing trade attention since the COVID-19 pandemic. Our convolutional neural networks were trained using online images (available from iNaturalist, Flickr and Google) displaying both traded and non-traded pangolin settings. The trained models showed great performances, being able to identify over 90 % of potential instances of pangolin trade in the considered imagery dataset. These instances included the showcasing of pangolins in popular marketplaces (e.g., wet markets and cages), and the displaying of commonly traded pangolin parts and derivates (e.g., scales) online. Nevertheless, not all instances of pangolin trade could be identified by our models (e.g., in images with dark colours and shaded areas), leaving space for further research developments. The methodological developments and results from this exploratory study represent an advancement in the monitoring of online wildlife trade. Complementing our approach with other forms of online data, such as text, would be a way forward to deliver more robust monitoring tools for online trafficking.
DOI: 10.1016/j.jece.2023.109645
2023
Cited 7 times
The characteristic evolution and formation mechanism of hybrid microalgae biofilm and its application in mariculture wastewater treatment
DOI: 10.3389/pore.2023.1611577
2024
Clinical and pathological observation of conversion therapy for malignant peritoneal mesothelioma: a case report and literature review
Background: Malignant mesothelioma (MM) is a tumor originating from the pleura, peritoneum, or pericardial cavity. It is divided into diffuse and localized malignant mesothelioma, with four subtypes in diffuse MM: epithelioid, sarcomatoid, desmoplastic, and biphasic, with biphasic being less common. The onset of this tumor is insidious, and the prognosis is extremely poor in some cases, with a median survival of 6-18 months and no standard treatment options in the past. Aims: We report a case of peritoneal malignant mesothelioma that was successfully treated with transformative therapy. We also review the literature in the hope of providing reference for the treatment and pathological diagnosis of such patients. Methods: The case of the peritoneal malignant mesothelioma was processed and reported in the routine manner for biopsy specimens at different stages. Results and conclusion: We report a case of a malignant tumor originating in the hepatorenal recess, which was diagnosed as biphasic malignant mesothelioma through a biopsy. Immunohistochemical testing showed PD-L1 expression. After multidisciplinary discussion, the patient received transformative treatment, including a trial of combined immunotherapy. The tumor significantly shrank, and the patient obtained a chance for curative surgical resection. Microscopic examination showed significant collagenization in the lesion area, with almost no residual tumor. After 19 months of comprehensive treatment, the patient developed multiple fluffy opacities under the pleura of both lungs. Transthoracic core needle biopsy under CT guidance, the pathology showed organizing pneumonia, considering it as delayed interstitial pneumonitis due to immunotherapy based on previous treatment history. Successful comprehensive treatment was achieved for this case of peritoneal malignant mesothelioma, and the patient has been alive without evidence of disease for 33 months, with long-term follow-up. In this process, the pathologist had three opportunities for pathological diagnosis, which required understanding the patient's medical history, being attentive to the clinical purpose of the specimen, and providing accurate responses to morphological changes at different stages, along with corresponding descriptions and diagnoses to provide effective information for clinical treatment.
DOI: 10.1016/j.redox.2024.103100
2024
IL-13 facilitates ferroptotic death in asthmatic epithelial cells via SOCS1-mediated ubiquitinated degradation of SLC7A11
Th2-high asthma is characterized by elevated levels of type 2 cytokines, such as interleukin 13 (IL-13), and its prevalence has been increasing worldwide. Ferroptosis, a recently discovered type of programmed cell death, is involved in the pathological process of Th2-high asthma; however, the underlying mechanisms remain incompletely understood. In this study, we demonstrated that the serum level of malondialdehyde (MDA), an index of lipid peroxidation, positively correlated with IL-13 level and negatively correlated with the predicted forced expiratory volume in 1 s (FEV1%) in asthmatics. Furthermore, we showed that IL-13 facilitates ferroptosis by upregulating of suppressor of cytokine signaling 1 (SOCS1) through analyzing immortalized airway epithelial cells, human airway organoids, and the ovalbumin (OVA)-challenged asthma model. We identified that signal transducer and activator of transcription 6 (STAT6) promotes the transcription of SOCS1 upon IL-13 stimulation. Moreover, SOCS1, an E3 ubiquitin ligase, was found to bind to solute carrier family 7 member 11 (SLC7A11) and catalyze its ubiquitinated degradation, thereby promoting ferroptosis in airway epithelial cells. Last, we found that inhibiting SOCS1 can decrease ferroptosis in airway epithelial cells and alleviate airway hyperresponsiveness (AHR) in OVA-challenged wide-type mice, while SOCS1 overexpression exacerbated the above in OVA-challenged IL-13-knockout mice. Our findings reveal that the IL-13/STAT6/SOCS1/SLC7A11 pathway is a novel molecular mechanism for ferroptosis in Th2-high asthma, confirming that targeting ferroptosis in airway epithelial cells is a potential therapeutic strategy for Th2-high asthma.
DOI: 10.4049/jimmunol.165.6.3119
2000
Cited 93 times
Impaired Affinity Maturation in<i>Cr2</i>−/− Mice Is Rescued by Adjuvants Without Improvement in Germinal Center Development
Cr2-/- mice have an impairment in humoral immunity, as shown by the decrease in the Ab titers against T cell-dependent Ags and abnormalities in germinal center formation. Germinal centers are present, but they are decreased in size and number, indicating problems in their development. In this study, we investigated whether this abnormality in germinal center development is associated with problems in the establishment of optimal affinity maturation and the generation of memory B cells, processes closely related to the germinal center reaction. We immunized the Cr2-/- animals with different Ags with or without adjuvants. We showed that, when immunized without adjuvants, complement receptors are absolutely required for optimal affinity maturation. Although limited affinity maturation is elicited in the Cr2-/- Ab response, it is decreased as compared with normal animals. Memory B cell generation is also impaired. In the presence of adjuvants, germinal center development in the Cr2-/- mice is still abnormal, as demonstrated by their decreased size and number. Surprisingly, adjuvants establish optimal affinity maturation and partially restore the amount of Ab produced during the primary response and memory B cell generation. However, adjuvants cannot improve the ability of follicular dendritic cells to retain Ags in the form of immune complexes. These observations indicate that immunization with inflammatory Ags offset some of the immunological abnormalities found in the Cr2-/- mice and show that optimal affinity maturation in the Cr2-/- mice can be achieved in the absence of normal germinal centers.
DOI: 10.1007/s12033-010-9274-5
2010
Cited 69 times
Reference Gene Selection for Real-Time RT-PCR in Eight Kinds of Rat Regenerating Hepatic Cells
DOI: 10.1002/ptr.3206
2010
Cited 62 times
Antiarrhythmic effects and ionic mechanisms of oxymatrine from <i>Sophora flavescens</i>
Abstract Accumulating evidence indicates that oxymatrine may exert protective effects on the cardiovascular system. This study was designed to evaluate the antiarrhythmic effects as well as the electrophysiological properties of oxymatrine. The antiarrhythmic activity of oxymatrine was observed in a rat model of arrhythmia induced by coronary ligation. Action potential duration (APD), L‐type calcium current (I Ca‐L ), transient outward potassium current (I to ) and inward rectifier potassium current (I K1 ) in rat ventricular myocytes were recorded by utilizing the whole cell patch‐clamp technique. The results showed that administration of oxymatrine significantly delayed the onset of ventricular arrhythmia, decreased the duration of ventricular arrhythmia and reduced the arrhythmia score of arrhythmic rats. The beneficial effects of oxymatrine may be related to the shortening of APD through reduction of I Ca‐L , enhancement of I to and inhibition of I K1 . Copyright © 2010 John Wiley &amp; Sons, Ltd.
DOI: 10.1016/j.ultras.2010.11.005
2011
Cited 59 times
Apoptosis of ovarian cancer cells induced by methylene blue-mediated sonodynamic action
The present study aims to investigate apoptosis of ovarian cancer cells induced by methylene blue (MB)-mediated sonodynamic therapy (SDT). The MB concentration was kept constant at 100 μM and ovarian cancer HO-8910 cells were exposed to ultrasound therapy for 5 s with an intensity of 0.46 W/cm2. The cytotoxicity was investigated 24 h after MB-mediated sonodynamic action. Apoptosis was analyzed using a flow cytometer with Annexin V-FITC and propidium iodine (PI) staining as well as fluorescence microscopy with Hoechst 33258 staining. Intracellular reactive oxygen species (ROS) level was measured by flow cytometer with 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) staining. The cytotoxicity of MB-mediated SDT on HO-8910 cells after MB-mediated SDT was significantly higher than those of other treatments including ultrasound alone, MB alone and sham treatment. Flow cytometric analysis showed a significant increase in the early and late apoptotic cell populations by MB-mediated SDT of HO-8910 cells. Nuclear condensation and increased ROS levels were also found in HO-8910 cells treated by MB-mediated SDT. Our findings demonstrated that MB-mediated sonodynamic action significantly induced apoptosis of HO-8910 cells and an increase in intracellular ROS level. This indicates that apoptosis is an important mechanism of cell death induced by MB-mediated SDT. Thus, MB-mediated SDT might be a potential therapeutic strategy for combating ovarian cancer.
DOI: 10.1186/s13578-015-0003-4
2015
Cited 50 times
Mediation of exogenous hydrogen sulfide in recovery of ischemic post-conditioning-induced cardioprotection via down-regulating oxidative stress and up-regulating PI3K/Akt/GSK-3β pathway in isolated aging rat hearts
The physiological and pathological roles of hydrogen sulfide (H2S) in the regulation of cardiovascular functions have been recognized. Cystathionine gamma-lyase (CSE) is a major H2S-producing enzyme in cardiovascular system. Ischemic post-conditioning (PC) provides cadioprotection in young hearts but lost in the aging hearts. The involvement of H2S in the recovery of PC-induced cardioprotection in the aging hearts is unclear. In the present study, we demonstrated that ischemia/reperfusion (I/R) decreased H2S production rate and CSE expression, aggravated cardiomyocytes damage, apoptosis and myocardial infarct size, reduced cardiac function, increased the levels of Bcl-2, caspase-3 and caspase-9 mRNA, enhanced oxidative stress in isolated young and aging rat hearts. I/R also increased the release of cytochrome c and down-regulated the phosphorylation of PI3K, Akt and GSK-3β in the aging rat hearts. We further found that PC increased H2S production rate and CSE expressions, and protected young hearts from I/R-induced cardiomyocytes damage, all of which were disappeared in the aging hearts. Supply of NaHS not only increased PC-induced cardioprotection in the young hearts, but also lightened I/R induced-myocardial damage and significantly recovered the cardioprotective role of PC against I/R induced myocardial damage in the aging hearts. LY294002 (a PI3K inhibitor) abolished but N-acetyl-cysteine (NAC, an inhibitor of reactive oxygen species, ROS) further enhanced the protective role of H2S against I/R induced myocardial damage in the aging hearts. In conclusion, these results demonstrate that exogenous H2S recovers PC-induced cardioprotection via inhibition of oxidative stress and up-regulation of PI3K-Akt-GSK-3β pathway in the aging rat hearts. These findings suggested that H2S might be a novel target for the treatment of aging cardiovascular diseases.
DOI: 10.1159/000430322
2015
Cited 49 times
Calhex231 Ameliorates Cardiac Hypertrophy by Inhibiting Cellular Autophagy in Vivo and in Vitro
Intracellular calcium concentration ([Ca2+]i) homeostasis, an initial factor of cardiac hypertrophy, is regulated by the calcium-sensing receptor (CaSR) and is associated with the formation of autolysosomes. The aim of this study was to investigate the role of Calhex231, a CaSR inhibitor, on the hypertrophic response via autophagy modulation.Cardiac hypertrophy was induced by transverse aortic constriction (TAC) in 40 male Wistar rats, while 10 rats underwent a sham operation and served as controls. Cardiac function was monitored by transthoracic echocardiography, and the hypertrophy index was calculated. Cardiac tissue was stained with hematoxylin and eosin (H&E) or Masson’s trichrome reagent and examined by transmission electron microscopy. An angiotensin II (Ang II)-induced cardiomyocyte hypertrophy model was established and used to test the involvement of active molecules. Intracellular calcium concentration ([Ca2+]i) was determined by the introduction of Fluo-4/AM dye followed by confocal microscopy. The expression of various active proteins was analyzed by western blot.The rats with TAC-induced hypertrophy had an increased heart size, ratio of heart weight to body weight, myocardial fibrosis, and CaSR and autophagy levels, which were suppressed by Calhex231. Experimental results using Ang II-induced hypertrophic cardiomyocytes confirmed that Calhex231 suppressed CaSR expression and downregulated autophagy by inhibiting the Ca2+/calmodulin-dependent-protein kinase-kinase-β (CaMKKβ)– AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) pathway to ameliorate cardiomyocyte hypertrophy.Calhex231 ameliorates myocardial hypertrophy induced by pressure-overload or Ang II via inhibiting CaSR expression and autophagy. Our results may support the notion that Calhex231 can become a new therapeutic agent for the treatment of cardiac hypertrophy.
DOI: 10.1159/000350091
2013
Cited 49 times
Role of the Calcium-Sensing Receptor in Cardiomyocyte Apoptosis via the Sarcoplasmic Reticulum and Mitochondrial Death Pathway in Cardiac Hypertrophy and Heart Failure
Aims: Alterations in calcium homeostasis in the intracellular endo/sarcoplasmic reticulum (ER/SR) and mitochondria of cardiomyocytes cause cell death via the SR and mitochondrial apoptotic pathway, contributing to ventricular dysfunction. However, the role of the calcium-sensing receptor (CaR) in cardiac hypertrophy and heart failure has not been studied. This study examined the possible involvement of CaR in the SR and mitochondrial apoptotic pathway in an experimental model of heart failure. Methods and Results: In Wistar rats, cardiac hypertrophy and heart failure were induced by subcutaneous injection of isoproterenol (Iso). Calindol, an activator of CaR, and calhex231, an inhibitor of CaR, were administered by caudal vein injection. Cardiac remodeling and left ventricular function were then analyzed in these rats. After 2, 4, 6 and 8 weeks after the administration of Iso, the rats developed cardiac hypertrophy and failure. The cardiac expression of ER chaperones and related apoptotic proteins was significantly increased in the failing hearts. Furthermore, the expression of ER chaperones and the apoptotic rate were also increased with the administration of calindol, whereas the expression of these proteins was reduced with the treatment of calhex231. We also induced cardiac hypertrophy and failure via thoracic aorta constriction (TAC) in mice. After 2 and 4 weeks of TAC, the expression of ER chaperones and apoptotic proteins were increased in the mouse hearts. Furthermore, Iso induced ER stress and apoptosis in cultured cardiomyocytes, while pretreatment with calhex231 prevented ER stress and protected the myocytes against apoptosis. To further investigate the effect of CaR on the concentration of intracellular calcium, the calcium concentration in the SR and mitochondria was determined with Fluo-5N and x-rhod-1 and the mitochondrial membrane potential was examined with JC-1 using laser confocal microscopy. After treatment with Iso for 48 hours, activation of CaR reduced [Ca2+]SR, increased [Ca2+]m, decreased the mitochondrial membrane potential, increased the expression of ER stress chaperones and related apoptotic proteins, and induced the release of cytochrome c from the mitochondria. Conclusions: Our results demonstrated that CaR activation caused Ca2+ release from the SR into the mitochondria and induced cardiomyocyte apoptosis through the SR and mitochondrial apoptotic pathway in failing hearts.
DOI: 10.1111/jcmm.12293
2014
Cited 48 times
Overexpression of miR‐483‐5p/3p cooperate to inhibit mouse liver fibrosis by suppressing the <scp>TGF</scp>‐β stimulated <scp>HSC</scp>s in transgenic mice
The transition from liver fibrosis to hepatocellular carcinoma (HCC) has been suggested to be a continuous and developmental pathological process. MicroRNAs (miRNAs) are recently discovered molecules that regulate the expression of genes involved in liver disease. Many reports demonstrate that miR-483-5p and miR-483-3p, which originate from miR-483, are up-regulated in HCC, and their oncogenic targets have been identified. However, recent studies have suggested that miR-483-5p/3p is partially down-regulated in HCC samples and is down-regulated in rat liver fibrosis. Therefore, the aberrant expression and function of miR-483 in liver fibrosis remains elusive. In this study, we demonstrate that overexpression of miR-483 in vivo inhibits mouse liver fibrosis induced by CCl4 . We demonstrate that miR-483-5p/3p acts together to target two pro-fibrosis factors, platelet-derived growth factor-β and tissue inhibitor of metalloproteinase 2, which suppress the activation of hepatic stellate cells (HSC) LX-2. Our work identifies the pathway that regulates liver fibrosis by inhibiting the activation of HSCs.
DOI: 10.1016/j.ultras.2015.05.003
2015
Cited 45 times
Sonodynamic action of curcumin on foodborne bacteria Bacillus cereus and Escherichia coli
Bacterial contamination is an important cause of foodborne diseases. The present study aimed to investigate sonodynamic action of curcumin on foodborne bacteria Bacillus cereus (B. cereus) and Escherichia coli (E. coli). The uptake of curcumin was measured for optimizing the concentration incubation time before ultrasound sonication, and colony forming units (CFU) were counted after ultrasound treatment. The chromosomal DNA fragmentation of bacteria was analyzed and the effect of hypoxic condition on the antibacterial efficacy of sonodynamic action of curcumin was also assessed in this study. The results showed that the maximum uptake of curcumin in B. cereus and E. coli occurred in 50min after curcumin incubation. Curcumin had sonodynamic bactericidal activity in a curcumin dose-dependent manner, and 5.6-log reduction in CFU of B. cereus was observed after curcumin treatment (2.0μM), however, only 2-log reduction in CFU of E. coli after 40μM curcumin treatment. No significant change in chromosomal DNA was found after the combined treatment of curcumin and ultrasound. The survival of B. cereus and E. coli after sonodynamic treatment in hypoxic group was significantly higher than that in normal oxygen group. These findings indicated that sonodynamic action of curcumin had significant inactivation effect on foodborne bacteria, and B. cereus was more sensitive to sonodynamic treatment of curcumin than E. coli. Sonodynamic antibacterial activity of curcumin might be dependent on the oxygen environment.
DOI: 10.1016/j.bbrc.2016.06.051
2016
Cited 44 times
miR-483-3p regulates hyperglycaemia-induced cardiomyocyte apoptosis in transgenic mice
Diabetic cardiomyopathy represents severe heart complications, and is the leading cause of morbidity and mortality among patients with diabetes. Although a few microRNAs (miRNAs) have been implicated in diabetes-related complications, a functional association between miRNAs and cardiac dysfunction in diabetic cardiomyopathy remains to be demonstrated. Our results show that miR-483-3p is upregulated in streptozotocin-induced diabetic mice, and cultured cardiomyocytes mimicking hyperglycemia. Overexpressing miR-483-3p in transgenic mice with diabetes mellitus (DM) exacerbated cardiomyocyte apoptosis by transcriptionally repressing insulin growth factor 1 (IGF1). Therefore, we have uncovered a novel signaling pathway, involving miR-483-3p-IGF1, that promotes myocardial cell apoptosis under high blood-glucose condition. Further, our study indicates that miR-483-3p could be a potential therapeutic target for managing diabetes-associated heart complications.
DOI: 10.1007/s00109-017-1616-3
2018
Cited 44 times
Exogenous H2S switches cardiac energy substrate metabolism by regulating SIRT3 expression in db/db mice
DOI: 10.1152/ajpheart.00245.2016
2017
Cited 43 times
The interaction of estrogen and CSE/H<sub>2</sub>S pathway in the development of atherosclerosis
Both estrogen and hydrogen sulfide (H 2 S) have been shown to inhibit the development of atherosclerosis. We previously reported that cystathionine γ-lyase knockout (CSE-KO) male mice develop atherosclerosis earlier than male wild-type (WT) mice. The present study investigated the interaction of CSE/H 2 S pathway and estrogen on the development of atherosclerosis in female mice. Plasma estrogen levels were significantly lower in female CSE-KO mice than in female WT mice. NaHS treatment had no effect on plasma estrogen levels in both WT and CSE-KO female mice. After CSE-KO and WT female mice were fed with atherogenic diet for 12 wk, plasma lipid levels were significantly increased and triglyceride levels decreased compared with those of control diet-fed mice. Atherogenic diet induced more atherosclerotic lesion, oxidative stress, intracellular adhesion molecule-1 (ICAM-1), and NF-κB in CSE-KO mice than in WT mice. Estrogen treatment of atherogenic diet-fed WT mice attenuated hypercholesterolemia, oxidative stress, ICAM-1 expression, and NF-κB in WT mice but not in atherogenic diet-fed CSE-KO mice. Furthermore, H 2 S production in both the liver and vascular tissues was enhanced by estrogen in WT mice but not in CSE-KO mice. It is concluded that the antiatherosclerotic effect of estrogen is mediated by CSE-generated H 2 S. This study provides new insights into the interaction of H 2 S and estrogen signaling pathways on the regulation of cardiovascular functions. NEW &amp; NOTEWORTHY Female cystathionine γ-lyase (CSE)-knockout mice have significantly lower plasma estrogen levels and more severe early atherosclerotic lesion than female wild-type mice. H 2 S production in liver and vascular tissues is enhanced by estrogen via its stimulatory effect on CSE activity. The antiatherosclerotic effect of estrogen is mediated by CSE-generated H 2 S.
DOI: 10.1021/acsami.8b11699
2018
Cited 42 times
Design of an Amphiphilic iRGD Peptide and Self-Assembling Nanovesicles for Improving Tumor Accumulation and Penetration and the Photodynamic Efficacy of the Photosensitizer
Photodynamic therapy (PDT) is a minimally invasive treatment for many diseases, including infections and tumors. Nevertheless, clinical utilization of PDT is severely restricted due to the shortcomings of the photosensitizers, especially their low water solubility and poor tumor selectivity. iRGD (internalizing RGD, CRGDKGPDC), a nine-unit cyclic peptide, was applied as an active ligand to realize tumor homing and tissue penetration. Herein, we innovatively fabricated a novel OFF-ON mode iRGD-based peptide amphiphile (PA) to self-assemble into spherical nanovesicles to enhance the tumor-targeting and tumor-penetrating efficacy of PDT. To introduce the self-assembling feature into iRGD, a hydrophilic arginine-rich sequence and hydrophobic alkyl chains were sequentially linked to the iRGD motif. A short proline sequence was selected to control the morphology of the self-assembled aggregates. Next, the photosensitizer hypocrellin B (HB) was encapsulated into PA vesicles with a high loading efficiency. The aggregation-caused quenching effect inactivated HB in the PA vesicles; however, the iRGD-peptide-based material was able to be selectively degraded in tumor cells. Thus, the HB fluorescence was recovered to achieve tumor-targeted imaging. This approach endows HB-loaded PA vesicles (HB-PA) with tumor-targeted activation, preferable tumor accumulation, and deep tumor penetration, thus leading to an excellent fluorescence-imaging-guided photodynamic efficacy both in vitro and in vivo. These amphiphilic iRGD aggregates provide a novel strategy for improving the accumulation, penetration, and imaging-guided photodynamic efficacy of photosensitizers.
DOI: 10.1002/cbin.11360
2020
Cited 30 times
Exogenous spermine attenuates myocardial fibrosis in diabetic cardiomyopathy by inhibiting endoplasmic reticulum stress and the canonical Wnt signaling pathway
Abstract Myocardial fibrosis is one of the main pathological manifestations of diabetic cardiomyopathy (DCM). Spermine (SPM), a product of polyamine metabolism, plays an important role in many cardiac diseases including hypertrophy, ischemia, and infarction, but its role in diabetic myocardial fibrosis has not been clarified. This study aimed to investigate the role of polyamine metabolism, specifically SPM, in diabetic myocardial fibrosis and to explore the related mechanisms. We used intraperitoneal injection of streptozotocin (STZ, 60 mg/kg) in Wistar rats and high glucose (HG, 40 mM) stimulated cardiac fibroblasts (CFs) to established a type 1 diabetes (T1D) model in vivo and in vitro, which were pretreated with exogenous SPM (5 mg/kg per day and 5 μM). The results showed that hyperglycemia induced the expression of the key polyamine synthesis enzyme ornithine decarboxylase (ODC) decreased and the key catabolic enzyme spermidine/spermine N 1 ‐acetyltransferase (SSAT) increased compared with those in the control group. The body weight, blood insulin level, and cardiac ejection function were decreased, while blood glucose, heart weight, the ratio of heart weight to body weight, myocardial interstitial collagen deposition, and endoplasmic reticulum stress (ERS)‐related protein (glucose‐regulated protein‐78, glucose‐regulated protein‐94, activating transcription factor‐4, and C/EBP homology protein) expression in the T1D group were all significantly increased. HG also caused an increased expression of Wnt3, β‐catenin (in cytoplasm and nucleus), while Axin2 and phosphorylated β‐catenin decreased. Exogenous SPM improved the above changes caused by polyamine metabolic disorders. In conclusion, polyamine metabolism disorder occurs in the myocardial tissue of diabetic rats, causing myocardial fibrosis and ERS. Exogenous SPM plays a myocardial protective role via inhibiting of ERS and the canonical Wnt/β‐catenin signaling pathway.
DOI: 10.1038/s43587-022-00348-z
2022
Cited 17 times
Age-related liver endothelial zonation triggers steatohepatitis by inactivating pericentral endothelium-derived C-kit
Aging leads to systemic metabolic disorders, including steatosis. Here we show that liver sinusoidal endothelial cell (LSEC) senescence accelerates liver sinusoid capillarization and promotes steatosis by reprogramming liver endothelial zonation and inactivating pericentral endothelium-derived C-kit, which is a type III receptor tyrosine kinase. Specifically, inhibition of endothelial C-kit triggers cellular senescence, perturbing LSEC homeostasis in male mice. During diet-induced nonalcoholic steatohepatitis (NASH) development, Kit deletion worsens hepatic steatosis and exacerbates NASH-associated fibrosis and inflammation. Mechanistically, C-kit transcriptionally inhibits chemokine (C-X-C motif) receptor (CXCR)4 via CCAAT enhancer-binding protein α (CEBPA). Blocking CXCR4 signaling abolishes LSEC-macrophage-neutrophil cross-talk and leads to the recovery of C-kit-deficient mice with NASH. Of therapeutic relevance, infusing C-kit-expressing LSECs into aged mice or mice with diet-induced NASH counteracts age-associated senescence and steatosis and improves the symptoms of diet-induced NASH by restoring metabolic homeostasis of the pericentral liver endothelium. Our work provides an alternative approach that could be useful for treating aging- and diet-induced NASH.
DOI: 10.1016/j.cej.2022.136794
2022
Cited 16 times
An engineered, self-propelled nanozyme as reactive oxygen species scavenger
BPQDs modified Janus Pt/SiO 2 nanomotors were constructed as self-propelled nanozymes, where asymmetric distributed Pt nanoparticles were the active centres to catalytically decomposing H 2 O 2 , O 2 - and OH. The nanozymes achieved more efficient self-diffusiophoretic motion under physiological concentration of H 2 O 2 as well as enhanced ability of eliminating OH and O 2 - , which greatly enhanced the ROS scavenging efficiency. • Introducing the concept of nanomotors into the field of nanozymes. • Systematic explores of the relationship between the motion and ROS scavenging activities of the self-propelled nanozymes. • Realized efficient motion of fuel-propelled nanomotors under physiological concentration of H 2 O 2. • The antioxidant ability of BPQDs for scavenging O 2 - and OH was exploited for the first time. The development of enzyme-mimicking nanomaterials (nanozymes) with excellent reactive oxygen species (ROS)-scavenging abilities and low biotoxicity is desired for clinical translation. The use of nanomotors as nanozymes for active ROS elimination is a novel strategy that involves rapid ROS diffusion through autonomous movement. Here, we report an engineered, self-propelled nanozyme based on a Janus Pt/SiO 2 nanomotor with Pt nanoparticle active centers, which possess GPx-like, CAT-like and SOD-like enzyme activities as well as ∙ OH scavenging ability. Nanozymes modified with black phosphorous quantum dots (BPQDs) achieved efficient self-diffusiophoretic motion under physiological concentrations of H 2 O 2 , independent of a fuel source. Moreover, the OH and O 2 - removal ability of BPQDs further improved antioxidant ability of this nanozyme. We hope that such strategy involving self-propulsion will facilitate the development of nanozymes and expand biomedical applications of nanomotors.
DOI: 10.1016/j.jallcom.2023.172622
2024
Effects of He and Ni ion irradiation on the ZrO2/Cr composite coating on Zr1Nb alloy
ZrO2/Cr composite coating has been irradiated by 2.8 MeV He and 38 MeV Ni ions at 350 °C. Similar extents of grain-growth and partial healing of microcracks have been identified in the ZrO2 layer of both irradiated samples. The monoclinic to tetragonal transformation of ZrO2 and the formation of an amorphous (Zr,Cr)O phase at the ZrO2/Cr interface is identified in the Ni-irradiated sample. Large amounts of dislocation loops and small cavities are observed in the Cr layer while significantly less loops are found in the ZrO2 layer in both samples. The irradiation processes also cause significant growth of surface Cr oxides.
DOI: 10.1016/j.porgcoat.2023.108204
2024
Synthesis, UV-curing behaviors and general properties of acrylate-urethane resins prepared from castor oil-based polyols
Castor oil-based polyols with high OH values are synthesized through the low odor thiol-ene reaction and then are used for preparing UV-curable acrylate-urethane resins (AUCORs). The structure of the AUCORs is confirmed by 1H NMR and IR. The AUCORs based resins containing diluents can rapidly form cured films under UV light irradiation in air, with a very high gel ratio of over 95 %. The UV-curing dynamics shows that polymerization rate and final acrylate conversion under the N2 atmosphere both depend on CC bond content, but they are reduced under air due to oxygen inhibition effect. All the cured films have good heat stability with an initial decomposition temperature over 300 °C. The cured films can display different Tg within the region of 55–85 °C depending on the crosslink density tuned by the acrylate/urethane content. The urethane content/diluter can affect some general properties of the coating films, for instance water absorption ability, wettability, hardness and adhesion force. Interestingly, the cured films have a very good light transmittance in the visible light region, as high as that of glass slides.
DOI: 10.53388/imd202408003
2024
Integration of network pharmacology and bone marrow mesenchymal stem cells experimental research to reveal the molecular mechanisms for Hai Honghua medicinal liquor against osteoporosis
DOI: 10.1038/s41467-024-45156-8
2024
A nanoparticle-based sonodynamic therapy reduces Helicobacter pylori infection in mouse without disrupting gut microbiota
Infection by Helicobacter pylori, a prevalent global pathogen, currently requires antibiotic-based treatments, which often lead to antimicrobial resistance and gut microbiota dysbiosis. Here, we develop a non-antibiotic approach using sonodynamic therapy mediated by a lecithin bilayer-coated poly(lactic-co-glycolic) nanoparticle preloaded with verteporfin, Ver-PLGA@Lecithin, in conjunction with localized ultrasound exposure of a dosage permissible for ultrasound medical devices. This study reveals dual functionality of Ver-PLGA@Lecithin. It effectively neutralizes vacuolating cytotoxin A, a key virulence factor secreted by H. pylori, even in the absence of ultrasound. When coupled with ultrasound exposure, it inactivates H. pylori by generating reactive oxygen species, offering a potential solution to overcome antimicrobial resistance. In female mouse models bearing H. pylori infection, this sonodynamic therapy performs comparably to the standard triple therapy in reducing gastric infection. Significantly, unlike the antibiotic treatments, the sonodynamic therapy does not negatively disrupt gut microbiota, with the only major impact being upregulation of Lactobacillus, which is a bacterium widely used in yogurt products and probiotics. This study presents a promising alternative to the current antibiotic-based therapies for H. pylori infection, offering a reduced risk of antimicrobial resistance and minimal disturbance to the gut microbiota.
DOI: 10.1016/j.tranon.2024.101895
2024
Revealing underlying regulatory mechanisms of LINC00313 in Osimertinib-resistant LUAD cells by ceRNA network analysis
Osimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), is the preferred treatment for EGFR-mutated lung cancer. However, acquired resistance inevitably develops. While non-coding RNAs have been implicated in lung cancer through various functions, the molecular mechanisms responsible for osimertinib resistance remain incompletely elucidated.RNA-sequencing technology was employed to determine differentially expressed lncRNAs (DE-lncRNAs) and mRNAs (DE-mRNAs) between H1975 and H1975OR cell lines. Starbase 2.0 was utilized to predict DE-lncRNA and DE-mRNA interactions, constructing ceRNA networks. Subsequently, functional and pathway enrichment analysis were performed on target DE-mRNAs to identify pathways associated with osimertinib resistance. Key target DE-mRNAs were then selected as potential risk signatures for lung adenocarcinoma (LUAD) prognostic modeling using multivariate Cox regression analyses. The Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and immunohistochemistry staining were used for result validation.Functional analysis revealed that the identified DE-mRNAs primarily enriched in EGFR-TKI resistance pathways, especially in the PI3K/Akt signaling pathway, where their concerted actions may lead to osimertinib resistance. Specifically, upregulation of LINC00313 enhanced COL1A1 expression by acting as a miR-218-5p sponge, triggering an upstream response that activates the PI3K/Akt pathway, potentially contributing to osimertinib resistance. Furthermore, the expressions of LINC00313 and COL1A1 were validated by qRT-PCR, and the activation of the PI3K/Akt pathway was confirmed by immunohistochemistry staining.Our results suggest that the LINC00313/miR-218-5p/COL1A1 axis potentially contributes to osimertinib resistance through the PI3K/Akt signaling pathway, providing novel insights into the molecular mechanisms underlying acquired osimertinib resistance in LUAD. Additionally, our study may aid in the identification of potential therapeutic targets for overcoming resistance to osimertinib.
DOI: 10.1016/j.bbrc.2006.06.176
2006
Cited 68 times
Involvement of calcium-sensing receptor in ischemia/reperfusion-induced apoptosis in rat cardiomyocytes
The calcium-sensing receptor (CaR) is a seven-transmembrane G-protein coupled receptor, which activates intracellular effectors, for example, it causes inositol phosphate (IP) accumulation to increase the release of intracellular calcium. Although intracellular calcium overload has been implicated in the cardiac ischemia/reperfusion (I/R)-induced apoptosis, the role of CaR in the induction of apoptosis has not been fully understood. This study tested the hypothesis that CaR is involved in I/R cardiomyocyte apoptosis by increasing [Ca2+]i. The isolated rat hearts were subjected to 40-min ischemia followed by 2 h of reperfusion, meanwhile GdCl3 was added to reperfusion solution. The expression of CaR increased at the exposure to GdCl3 during I/R. By laser confocal microscopy, it was observed that the intracellular calcium was significantly increased and exhibited a Deltapsim, as monitored by 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolcarbocyanine iodide (JC-1) during reperfusion with GdCl3. Furthermore, the number of apoptotic cells was significantly increased as shown by TUNEL assay. Typical apoptotic cells were observed with transmission electron microscopy in I/R with GdCl3 but not in the control group. The expression of cytosolic cytochrome c and activated caspase-9 and caspase-3 was significantly increased whereas the expression of mitochondrial cytochrome c significantly decreased in I/R with GdCl3 in comparison to the control. In conclusion, these results suggest that CaR is involved in the induction of cardiomyocyte apoptosis during ischemia/reperfusion through activation of cytochrome c-caspase-3 signaling pathway.
DOI: 10.1016/j.bbrc.2006.09.142
2006
Cited 61 times
Calcium-sensing receptor induces rat neonatal ventricular cardiomyocyte apoptosis
The calcium-sensing receptor (CaSR) exists in many tissues, and its expression has been identified in rat cardiac tissue. However, the physiological importance and pathophysiological involvement of CaSR in homeostatic regulation of cardiac function are unclear. To investigate the relation of CaSR and apoptosis in cardiomyocytes, we examined the role of the CaSR activator gadolinium chloride (GdCl(3)) in rat neonatal ventricular cardiomyocytes. Expression of the CaSR protein was observed by Western blot. The apoptotic ratio of rat neonatal ventricular cardiomyocytes was measured with flow cytometry and immunofluorescence techniques. A laser scan confocal microscope was used to detect the intracellular concentration of calcium ([Ca(2+)](i)) in rat neonatal ventricular cardiomyocytes using the acetoxymethyl ester of fluo-3 (fluo-3/(AM)) as a fluorescent dye. The results showed that GdCl(3) increased the phosphorylation of extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal protein kinases (JNK), and p38. GdCl(3) also activated caspase 9 and increased apoptosis in myocyte by increasing [Ca(2+)](i). In conclusion, these results suggest that CaSR promotes cardiomyocyte apoptosis in rat neonatal ventricular cardiomyocytes through activation of mitogen-activated protein kinases and caspase 9 signaling pathways.
DOI: 10.1186/1423-0127-18-18
2011
Cited 52 times
Role of dopamine D2 receptors in ischemia/reperfusion induced apoptosis of cultured neonatal rat cardiomyocytes
Myocardial ischemia/reperfusion injury is the major cause of morbidity and mortality for cardiovascular diseases. Dopamine D2 receptors are expressed in cardiac tissues. However, the roles of dopamine D2 receptors in myocardial ischemia/reperfusion injury and cardiomyocyte apoptosis are unclear. Here we investigated the effects of both dopamine D2 receptors agonist (bromocriptine) and antagonist (haloperidol) on apoptosis of cultured neonatal rat ventricular myocytes induced by ischemia/reperfusion injury.Myocardial ischemia/reperfusion injury was simulated by incubating primarily cultured neonatal rat cardiomyocytes in ischemic (hypoxic) buffer solution for 2 h. Thereafter, these cells were incubated for 24 h in normal culture medium.Treatment of the cardiomyocytes with 10 μM bromocriptine significantly decreased lactate dehydrogenase activity, increased superoxide dismutase activity, and decreased malondialdehyde content in the culture medium. Bromocriptine significantly inhibited the release of cytochrome c, accumulation of [Ca2+]i, and apoptosis induced by ischemia/reperfusion injury. Bromocriptine also down-regulated the expression of caspase-3 and -9, Fas and Fas ligand, and up-regulated Bcl-2 expression. In contrast, haloperidol (10 μM) had no significant effects on the apoptosis of cultured cardiomyocytes under the aforementioned conditions.These data suggest that activation of dopamine D2 receptors can inhibit apoptosis of cardiomyocytes encountered during ischemia/reperfusion damage through various pathways.
DOI: 10.1007/s11010-010-0450-5
2010
Cited 49 times
Post-conditioning protects cardiomyocytes from apoptosis via PKCε-interacting with calcium-sensing receptors to inhibit endo(sarco)plasmic reticulum–mitochondria crosstalk
DOI: 10.1007/s11010-013-1686-7
2013
Cited 46 times
Exogenous hydrogen sulfide prevents cardiomyocyte apoptosis from cardiac hypertrophy induced by isoproterenol
DOI: 10.1016/j.brainres.2014.05.019
2014
Cited 43 times
Angiotensin-(1-7) improves cognitive function in rats with chronic cerebral hypoperfusion
Chronic cerebral hypoperfusion (CCH) is associated with cognitive decline in aging, vascular dementia and Alzheimer׳s disease. Recently, angiotensin-(1-7) (Ang-(1-7)), one of the physiological constituents of the brain, was found to protect against cognitive dysfunction and brain ischemia. However, the effects of Ang-(1-7) on CCH-induced cognitive deficits remained unknown. In the present study, Ang-(1-7) significantly alleviated CCH-induced cognitive deficits in rats subjected to permanent bilateral occlusion of the common carotid arteries (a model of CCH). This neuroprotective effect was associated with increased nitric oxide generation, attenuated neuronal loss and suppressed astrocyte proliferation in the hippocampus. These findings demonstrate that Ang-(1-7) is a promising therapeutic agent for CCH-induced cognitive deficits.
DOI: 10.1016/j.ultras.2011.11.007
2012
Cited 43 times
Hypocrellin B-mediated sonodynamic action induces apoptosis of hepatocellular carcinoma cells
The present study aims to investigate apoptosis of hepatocellular carcinoma cells induced by hypocrellin B-mediated sonodynamic action. The hypocrellin B concentration was kept constant at 2.5 μM and cells from the hepatocellular carcinoma HepG2 cell line were exposed to ultrasound with an intensity of 0.46 W/cm2 for 8 s. Cell cytotoxicity was quantified using an MTT assay 24 h after sonodynamic therapy (SDT) of hypocrellin B. Apoptosis was investigated using a flow cytometry with Annexin V-FITC and propidium iodine staining. Intracellular reactive oxygen species (ROS) levels were detected using a flow cytometry with 2,7-dichlorodihydrofluorecein diacetate (DCFH-DA) staining. The cytotoxicity of hypocrellin B-mediated sonodynamic action on HepG2 cells was significantly higher than those of other treatments including ultrasound alone, hypocrellin B alone and sham treatment. Flow cytometry showed that hypocrellin B-induced sonodynamic action markedly enhanced the apoptotic rate of HepG2 cells. Increased ROS was observed in HepG2 cells after being treated with hypocrellin B-mediated sonodynamic action. Our data demonstrated that hypocrellin B-mediated sonodynamic action remarkably induced apoptosis of HepG2 cells, suggesting that apoptosis is an important mechanism of cell death induced by hypocrellin B-mediated SDT.
DOI: 10.1016/j.molimm.2012.09.010
2013
Cited 39 times
Expression of the calcium sensing receptor in human peripheral blood T lymphocyte and its contribution to cytokine secretion through MAPKs or NF-κB pathways
The calcium-sensing receptor (CaSR) has been reported to play an important role in many tissues and organs. However, studies about the expression and function of CaSR in T lymphocytes are still not very lucid. In this study, we investigated the above-mentioned issues using RT-PCR, immunofluorescence staining, Western blotting, and the ELISA techniques. We found that the CaSR protein was expressed, and mainly located in the membrane in the normal human peripheral blood T lymphocytes. GdCl3 (an agonist of CaSR) increased the dose-dependency of the CaSR expression, which was abolished by NPS2390 (an inhibitor of CaSR). GdCl3 and Ca2+ increased the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 (one subgroup of MAPKs) and P65 (subunit of NF-κB),but, they had no significant effects on the JNK and P38 subgroups of MAPKs. Meantime, GdCl3 and Ca2+ stimulated both the IL-6 and TNF-β releases and their mRNA expressions. However, these effects of GdCl3 and Ca2+ were inhibited by NPS2390, U0126 (MAPKs pathway inhibitor) or Bay-11-7082 (NF-κB pathway inhibitor). These results suggested that CaSR was functionally expressed in the T cells, and the activated CaSR contributed to the cytokine secretion through the partial MAPK and NF-κB pathways.
DOI: 10.1152/ajpendo.00196.2016
2017
Cited 39 times
Exogenous H<sub>2</sub>S regulates endoplasmic reticulum-mitochondria cross-talk to inhibit apoptotic pathways in STZ-induced type I diabetes
The upregulation of reactive oxygen species (ROS) is a primary cause of cardiomyocyte apoptosis in diabetes cardiomyopathy (DCM). Mitofusin-2 (Mfn-2) is a key protein that bridges the mitochondria and endoplasmic reticulum (ER). Hydrogen sulfide (H 2 S)-mediated cardioprotection is related to antioxidant effects. The present study demonstrated that H 2 S inhibited the interaction between the ER and mitochondrial apoptotic pathway. This study investigated cardiac function, ultrastructural changes in the ER and mitochondria, apoptotic rate using TUNEL, and the expression of ER stress-associated proteins and mitochondrial apoptotic proteins in cardiac tissues in STZ-induced type I diabetic rats treated with or without NaHS (donor of H 2 S). Mitochondria of cardiac tissues were isolated, and MPTP opening and cytochrome c (cyt C) and Mfn-2 expression were also detected. Our data showed that hyperglycemia decreased the cardiac function by ultrasound cardiogram, and the administration of exogenous H 2 S ameliorated these changes. We demonstrated that the expression of ER stress sensors and apoptotic rates were elevated in cardiac tissue of DCM and cultured H9C2 cells, but the expression of these proteins was reduced following exogenous H 2 S treatment. The expression of mitochondrial apoptotic proteins, cyt C, and mPTP opening was decreased following treatment with exogenous H 2 S. In our experiment, the expression and immunofluorescence of Mfn-2 were both decreased after transfection with Mfn-2-siRNA. Hyperglycemia stimulated ER interactions and mitochondrial apoptotic pathways, which were inhibited by exogenous H 2 S treatment through the regulation of Mfn-2 expression.
DOI: 10.1159/000358634
2014
Cited 38 times
Calcium Sensing Receptor Promotes Cardiac Fibroblast Proliferation and Extracellular Matrix Secretion
Calcium-sensing receptor (CaR) acts as a G protein coupled receptor that mediates the increase of the intracellular Ca(2+) concentration. The expression of CaR has been confirmed in various cell types, including cardiomyocytes, smooth muscle cells, neurons and vascular endothelial cells. However, whether CaR is expressed and functions in cardiac fibroblasts has remained unknown. The present study investigated whether CaR played a role in cardiac fibroblast proliferation and extracellular matrix (ECM) secretion, both in cultured rat neonatal cardiac fibroblasts and in a model of cardiac hypertrophy induced by isoproterenol (ISO).Immunofluorescence, immunohistochemistry and Western blot analysis revealed the presence of CaR in cardiac fibroblasts. Calcium and calindol, a specific activator of CaR, elevated the intracellular calcium concentration in cardiac fibroblasts. Pretreatment of cardiac fibroblasts with calhex231, a specific inhibitor of CaR, U73122 and 2-APB attenuated the calindol- and extracellular calcium-induced increase in intracellular calcium ([Ca(2+)]i). Cardiac fibroblast proliferation and migration were assessed by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), cell count and the cell scratch assay. ECM production was detected by expression of matrix metalloproteinase-3 and -9 (MMP-3 and -9). Activation of CaR promoted cardiac fibroblast proliferation and migration and ECM secretion. More importantly, calhex231, suppressed cardiac fibroblast proliferation and migration and MMP-3 and -9 expression. To further investigate the effect of CaR on cardiac fibrosis, a model of ISO-induced cardiac hypertrophy was established. Pretreatment with calhex231 prevented cardiac fibrosis and decreased the expression of MMP-3 and -9 expression.Our results are the first report that CaR plays an important role in Ca(2+) signaling involved in cardiac fibrosis through the phospholipase C- inositol 3,4,5 phosphate (PLC-IP3) pathway.
DOI: 10.1016/j.pdpdt.2016.07.006
2016
Cited 38 times
Palmatine hydrochloride mediated photodynamic inactivation of breast cancer MCF-7 cells: Effectiveness and mechanism of action
Breast cancer is one of the commonest malignant tumors threatening to women. The present study aims to investigate the effect of photodynamic action of palmatine hydrochloride (PaH), a naturally occurring photosensitizer isolated from traditional Chinese medicine (TCM), on apoptosis of breast cancer cells. Firstly, cellular uptake of PaH in MCF-7 cells was measured and the cytotoxicity of PaH itself on breast cancer MCF-7 cells was estimated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Subcellular localization of PaH in MCF-7 cells was observed using confocal laser scanning microscopy (CLSM). For photodynamic treatment, MCF-7 cells were incubated with PaH and then irradiated by visible light (470nm) from a LED light source. Photocytotoxicity was investigated 24h after photodynamic treatment using MTT assay. Cell apoptosis was analyzed 18h after photodynamic treatment using flow cytometry with Annexin V/PI staining. Nuclear was stained using Hoechst 33342 and observed under a fluorescence microscope. Intracellular production of reactive oxygen species (ROS) was studied by measuring the fluorescence of 2, 7-dichlorofluorescein (DCF) using a flow cytometry. Results showed that PaH treatment alone had no or minimum cytotoxicity to MCF-7 cells after incubation for 24h in the dark. After incubation for 40min, the cellular uptake of PaH reached to the maximum, and PaH mainly located in mitochondria and endoplasmic reticulum of MCF-7 cells. Photodynamic treatment of PaH demonstrated a significant photocytotoxicity on MCF-7 cells, induced remarkable cell apoptosis and significantly increased intracellular ROS level. Our findings demonstrated that PaH as a naturally occurring photosensitizer induced cell apoptosis and significantly killed MCF-7 cells.
DOI: 10.3390/ijms18091958
2017
Cited 38 times
Thioredoxin 2 Offers Protection against Mitochondrial Oxidative Stress in H9c2 Cells and against Myocardial Hypertrophy Induced by Hyperglycemia
Mitochondrial oxidative stress is thought to be a key contributor towards the development of diabetic cardiomyopathy.Thioredoxin 2 (Trx2) is a mitochondrial antioxidant that, along with Trx reductase 2 (TrxR2) and peroxiredoxin 3 (Prx3), scavenges H 2 O 2 and offers protection against oxidative stress.Our previous study showed that TrxR inhibitors resulted in Trx2 oxidation and increased ROS emission from mitochondria.In the present study, we observed that TrxR inhibition also impaired the contractile function of isolated heart.Our studies showed a decrease in the expression of Trx2 in the high glucose-treated H9c2 cardiac cells and myocardium of streptozotocin (STZ)-induced diabetic rats.Overexpression of Trx2 could significantly diminish high glucose-induced mitochondrial oxidative damage and improved ATP production in cultured H9c2 cells.Notably, Trx2 overexpression could suppress high glucose-induced atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) gene expression.Our studies suggest that high glucose-induced mitochondrial oxidative damage can be prevented by elevating Trx2 levels, thereby providing extensive protection to the diabetic heart.
DOI: 10.1038/cr.2014.65
2014
Cited 37 times
No receptor stands alone: IgG B-cell receptor intrinsic and extrinsic mechanisms contribute to antibody memory
Acquired immunological memory is a striking phenomenon. A lethal epidemic sweeps through a naïve population, many die but those who survive are never "attacked twice - never at least fatally", as the historian Thucydides observed in 430 BCE. Antibody memory is critical for protection against many human infectious diseases and is the basis for nearly all current human vaccines. Antibody memory is encoded, in part, in isotype-switched immunoglobulin (Ig)G-expressing memory B cells that are generated in the primary response to antigen and give rise to rapid, high-affinity and high-titered antibody responses upon challenge with the same antigen. How IgG-B-cell receptors (BCRs) and antigen-induced IgG-BCR signaling contribute to memory antibody responses are not fully understood. In this review, we summarize exciting new advances that are revealing the cellular and molecular mechanisms at play in antibody memory and discuss how studies using different experimental approaches will help elucidate the complex phenomenon of B-cell memory.
DOI: 10.1016/j.carbpol.2014.06.059
2014
Cited 37 times
Investigation of inclusion complex of honokiol with sulfobutyl ether-β-cyclodextrin
This study aimed to prepare and characterize an inclusion complex of honokiol (HNK) with sulfobutyl ether-β-cyclodextrin (SB-β-CD). The inclusion complex (HNK/CD COMP) was prepared utilizing a freeze-drying method. Phase-solubility curves were employed to obtain stability constants and thermodynamic parameters. The phase-solubility diagram showed a typical A(L)-type, indicating that the 1:1 (HNK:SB-β-CD) inclusion complex was formed. The solid inclusion complex was then characterized by differential scanning calorimetry and Fourier transform infrared spectroscopy. Results showed that HNK/CD COMP exhibited a higher drug release rate than free HNK in vitro. A comparative study of the pharmacokinetics between HNK/CD COMP and free HNK was also performed in rats. In vivo results indicated that AUC0-t and Cmax of HNK/CD COMP increased by approximately 158% and 123% compared with those of the free HNK, respectively. These results suggest that SB-β-CD will be potentially useful in the delivery of poorly soluble drugs, such as HNK.
DOI: 10.1186/s13578-015-0035-9
2015
Cited 37 times
Exogenous hydrogen sulfide restores cardioprotection of ischemic post-conditioning via inhibition of mPTP opening in the aging cardiomyocytes
The physiological and pathological roles of hydrogen sulfide (H2S) in the regulation of cardiovascular functions have been recognized. H2S protects against the hypoxia/reoxygenation (H/R)-induced injury and apoptosis of cardiomyocytes, and ischemic post-conditioning (PC) plays an important role in cardioprotection from H/R injury in neonatal cardiomyocytes but not in aging cardiomyocytes. Whether H2S is involved in the recovery of PC-induced cardioprotection in aging cardiomyocytes is unclear. In the present study, we found that both H/R and PC decreased cystathionine-γ-lyase (CSE) expression and the production rate of H2S. Supplementation of NaHS protected against H/R-induced apoptosis, the expression of cleaved caspase-3 and cleaved caspase-9, the release of cytochrome c (Cyt c), and mPTP opening. The addition of NaHS also counteracted the reduction of cell viability caused by H/R and increased the phosphorylation of ERK1/2, PI3K, Akt, GSK-3β and mitochondrial membrane potential. Additionally, NaHS increased Bcl-2 expression, promoted PKC-ε translocation to the cell membrane, and activated mitochondrial ATP-sensitive K channels (mitoKATP). PC alone did not provide cardioprotection in H/R-treated aging cardiomyocytes, which was significantly restored by the supplementation of NaHS. In conclusion, our results suggest that exogenous H2S restores PC-induced cardioprotection via the inhibition of mPTP opening by the activation of the ERK1/2-GSK-3β, PI3K-Akt-GSK-3β and PKC-ε-mitoKATP pathways in aging cardiomyocytes. These findings provide a novel target for the treatment of aging ischemic cardiomyopathy.
DOI: 10.1159/000438648
2016
Cited 37 times
Spermine inhibits Endoplasmic Reticulum Stress - induced Apoptosis: a New Strategy to Prevent Cardiomyocyte Apoptosis
Background/Aims: Endoplasmic reticulum stress (ERS) plays an important role in the progression of acute myocardial infarction (AMI), in part by mediating apoptosis. Polyamines, including putrescine, spermidine, and spermine, are polycations with anti-oxidative, anti-aging, and cell growth-promoting activities. This study aimed to determine the mechanisms by which spermine protects against ERS-induced apoptosis in rats following AMI. Methods and Results: AMI was established by ligation of the left anterior descending coronary artery (LAD) in rats, and exogenous spermine was administered by intraperitoneal injection (2.5 mg/ml daily for 7 days pre-AMI). Spermine treatment limited infarct size, attenuated cardiac troponin I and creatinine kinase-MB release, improved cardiac function, and decreased ERS and apoptosis related protein expression. Isolated cardiomyocytes subjected to hypoxia showed significant increase in reactive oxygen species (ROS) and the expression of apoptosis and ERS related proteins; these effects occurred through PERK and eIF2α phosphorylation. The addition of spermine attenuated cardiomyocyte apoptosis, suppressed the production of ROS, and inhibited ERS related pathways. Conclusions: Spermine was an effective pre-treatment strategy to attenuate cardiac ERS injury in rats, and the cardioprotective mechanism occurring through inhibition of ROS production and down regulation of the PERK-eIF2α pathway. These findings provide a novel target for the prevention of apoptosis in the setting of AMI.
DOI: 10.1038/cddis.2017.380
2017
Cited 35 times
Exogenous H2S facilitating ubiquitin aggregates clearance via autophagy attenuates type 2 diabetes-induced cardiomyopathy
Abstract Diabetic cardiomyopathy (DCM) is a serious complication of diabetes. Hydrogen sulphide (H 2 S), a newly found gaseous signalling molecule, has an important role in many regulatory functions. The purpose of this study is to investigate the effects of exogenous H 2 S on autophagy and its possible mechanism in DCM induced by type II diabetes (T2DCM). In this study, we found that sodium hydrosulphide (NaHS) attenuated the augment in left ventricular (LV) mass and increased LV volume, decreased reactive oxygen species (ROS) production and ameliorated H 2 S production in the hearts of db/db mice. NaHS facilitated autophagosome content degradation, reduced the expression of P62 (a known substrate of autophagy) and increased the expression of microtubule-associated protein 1 light chain 3 II. It also increased the expression of autophagy-related protein 7 (ATG7) and Beclin1 in db/db mouse hearts. NaHS increased the expression of Kelch-like ECH-associated protein 1 (Keap-1) and reduced the ubiquitylation level in the hearts of db/db mice. 1,4-Dithiothreitol, an inhibitor of disulphide bonds, increased the ubiquitylation level of Keap-1, suppressed the expression of Keap-1 and abolished the effects of NaHS on ubiquitin aggregate clearance and ROS production in H9C2 cells treated with high glucose and palmitate. Overall, we concluded that exogenous H 2 S promoted ubiquitin aggregate clearance via autophagy, which might exert its antioxidative effect in db/db mouse myocardia. Moreover, exogenous H 2 S increased Keap-1 expression by suppressing its ubiquitylation, which might have an important role in ubiquitin aggregate clearance via autophagy. Our findings provide new insight into the mechanisms responsible for the antioxidative effects of H 2 S in the context of T2DCM.
DOI: 10.1002/jcp.28400
2019
Cited 33 times
TRIM72 contributes to cardiac fibrosis via regulating STAT3/Notch‐1 signaling
Cardiac fibrosis is a pathophysiological process characterized by excessive deposition of extracellular matrix. We developed a cardiac hypertrophy model using transverse aortic constriction (TAC) to uncover mechanisms relevant to excessive deposition of extracellular matrix in mouse myocardial cells. TAC caused upregulation of Tripartite motif protein 72 (TRIM72), a tripartite motif-containing protein that is critical for proliferation and migration. Importantly, in vivo silencing of TRIM72 reversed TAC-induced cardiac fibrosis, as indicated by markedly increased left ventricular systolic pressure and decreased left ventricular end-diastolic pressure. TRIM72 knockdown also attenuated deposition of fibrosis marker collagen type I and α-smooth muscle actin (α-SMA). In an in vitro study, TRIM72 was similarly upregulated in cardiac fibroblasts. Knockdown of TRIM72 markedly suppressed collagen type I and α-SMA expression and significantly decreased the proliferation and migration of cardiac fibroblasts. However, TRIM72 overexpression markedly increased collagen type I and α-SMA expression and increased the proliferation and migration of cardiac fibroblasts. Further study demonstrated that TRIM72 increased phosphorylated STAT3 in cardiac fibroblasts. TRIM72 knockdown in cardiac fibroblasts resulted in increased expression of Notch ligand Jagged-1 and its downstream gene and Notch-1 intracellular domain. Inhibition of Notch-1 abrogated sh-TRIM72-induced cardiac fibrosis. Together, our results support a novel role for TRIM72 in maintaining fibroblast-to-myofibroblast transition and suppressing fibroblast growth by regulating the STAT3/Notch-1 pathway.
DOI: 10.1021/acs.analchem.9b04596
2019
Cited 30 times
Facile Strategy To Enhance Specificity and Sensitivity of Molecular Beacons by an Aptamer-Functionalized Delivery Vector
To enhance the specificity and sensitivity of molecular beacons (MBs) in detecting mRNA in living tumor cells, we introduced an aptamer (AS1411) to the delivery system of MBs to form an aptamer-decorated nanoprobe (ANP), which was prepared through self-assembly between AS1411-conjugated carboxymethyl chitosan (ACMC) with protamine sulfate (PS)/CaCO3/MB cores. Owing to the specific binding of AS1411 to nucleolin, which is overexpressed in tumor cell membranes and nuclei, an AS1411-decorated MB-delivery system leads to dramatically increased cell uptake of MBs for probing survivin mRNA and thus induces strong intracellular fluorescence emission in targeted tumorous cells and cell nuclei. Furthermore, we demonstrate that ANP can efficiently detect survivin mRNA in mitochondria. In other words, the effective delivery of MBs ensures the precise detection of mRNA distribution in diverse organelles. In addition, we evaluated the efficiency of ANP in probing tumor cells in simulated blood as well as in peripheral blood from a healthy donor and found that the nanoprobe can specifically deliver MBs to tumor cells and identify tumor cells in blood. The targeting delivery system we constructed holds promising applications in precise detection of subcellular distribution of mRNA in living tumor cells as well as in fluorescence-guided cancer detection in liquid biopsy technology. This study provides a facile strategy to effectively improve the specificity and sensitivity of conventional molecular beacons.
DOI: 10.3389/fimmu.2021.753929
2021
Cited 20 times
Identification and Clinical Validation of Key Extracellular Proteins as the Potential Biomarkers in Relapsing-Remitting Multiple Sclerosis
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) mediated by autoimmunity. No objective clinical indicators are available for the diagnosis and prognosis of MS. Extracellular proteins are most glycosylated and likely to enter into the body fluid to serve as potential biomarkers. Our work will contribute to the in-depth study of the functions of extracellular proteins and the discovery of disease biomarkers.MS expression profiling data of the human brain was downloaded from the Gene Expression Omnibus (GEO). Extracellular protein-differentially expressed genes (EP-DEGs) were screened by protein annotation databases. GO and KEGG were used to analyze the function and pathway of EP-DEGs. STRING, Cytoscape, MCODE and Cytohubba were used to construct a protein-protein interaction (PPI) network and screen key EP-DEGs. Key EP-DEGs levels were detected in the CSF of MS patients. ROC curve and survival analysis were used to evaluate the diagnostic and prognostic ability of key EP-DEGs.We screened 133 EP-DEGs from DEGs. EP-DEGs were enriched in the collagen-containing extracellular matrix, signaling receptor activator activity, immune-related pathways, and PI3K-Akt signaling pathway. The PPI network of EP-DEGs had 85 nodes and 185 edges. We identified 4 key extracellular proteins IL17A, IL2, CD44, IGF1, and 16 extracellular proteins that interacted with IL17A. We clinically verified that IL17A levels decreased, but Del-1 and resolvinD1 levels increased. The diagnostic accuracy of Del-1 (AUC: 0.947) was superior to that of IgG (AUC: 0.740) with a sensitivity of 82.4% and a specificity of 100%. High Del-1 levels were significantly associated with better relapse-free and progression-free survival.IL17A, IL2, CD44, and IGF1 may be key extracellular proteins in the pathogenesis of MS. IL17A, Del-1, and resolvinD1 may co-regulate the development of MS and Del-1 is a potential biomarker of MS. We used bioinformatics methods to explore the biomarkers of MS and validated the results in clinical samples. The study provides a theoretical and experimental basis for revealing the pathogenesis of MS and improving the diagnosis and prognosis of MS.
DOI: 10.1016/j.jconrel.2022.02.012
2022
Cited 12 times
A targeting delivery system for effective genome editing in leukemia cells to reverse malignancy
Therapy resistance associated with relapse is a main cause of death in acute myeloid leukemia (AML). To address this issue, a dual-targeting CRISPR-Cas9 genome editing nanosystem was constructed for CXCR4 knockout to reverse the malignancy of leukemia cells. The surface of the dual-targeting nanosystem is composed of MUC1 specific aptamer incorporated alginate (MUC1 aptamer-alginate) and T22-NLS peptide with T22 sequence targeting CXCR4; the core of the nanosystem consists of protamine complexed with CRISPR-Cas9 plasmid. The in vitro study shows that the nanosystem mediated genome editing induces cell apoptosis, cell cycle arrest, as well as inhibited cell migration and adhesion in edited THP-1 cells after CXCR4 knockout. Further, the unprocessed peripheral blood from acute myeloid leukemia (AML) patients was directly used to carry out ex vivo study. The results show the genome editing nanosystem can effectively knock out CXCR4 in leukemia cells, leading to attenuated CXCR4 protein as studied by antibody labeling and reduced CXCR4 mRNA as probed by a molecular beacon delivery system. In addition to developing a promising delivery vector for gene therapy on AML, this study also provides an effective strategy to evaluate the therapeutic efficiency of particular treatments by peripheral blood-based ex vivo studies.
DOI: 10.1088/1402-4896/acb242
2023
Cited 5 times
Optimal design of broadband acoustic metasurface absorbers
Abstract The absorption of low-frequency noise has always been limited by structural thickness, but the novel physical properties of sound-absorbing metamaterials provide a solution to this problem. Based on genetic algorithm, an acoustic metasurface absorber (AMA) composed of micro-perforated plates (MPPs) and impedance matching coiled-up cavities (IMCCs) is proposed. Different from previously reported metamaterials, this structure can easily provide flexible and accurate broadband sound absorption in different target frequency bands. The theoretical model behind the algorithm is established, and two optimal structures (AMA I/AMA II) are obtained for low and mid-high frequency bands. Broadband sound absorption is realized with a thickness of only 71 mm (about 1/13 of the relevant wavelength at 369 Hz), and an average sound absorption coefficient of 0.931 is achieved in the low-frequency band of 350–1000 Hz. Furthermore, by changing the frequency band of the quasi-perfect absorber to 500–2000 Hz, the average sound absorption coefficient exceeds 0.945 with a thickness of only 55 mm (about 1/11 of the relevant wavelength at 563 Hz). The reflection coefficient in the complex plane and theoretical impedance analysis are utilized to reveal the underlying mechanism of the absorption and the acoustic characteristics of the two structures, which show excellent broadband absorption performance in the low and mid-high frequency bands. This work provides a method of arbitrarily modulating surface acoustic impedance in broadband and a reference for broadband noise control.
DOI: 10.20517/cs.2023.08
2023
Cited 5 times
Nanodiamond derived N-doped sp3@sp2 hybrid carbocatalysts for the aerobic oxidative synthesis of 2-substituted benzoxazoles
Carbocatalysts, as a member of metal-free catalysts, have shown promising potentials in many catalytic transformations in the past few decades. Nitrogen doping has been identified as an effective way to tailor the properties of carbocatalysts and render their potential use for various applications. It is also important to fabricate unique surface compositions or properties for the N species to enhance their intrinsic catalytic activities. Hybrid sp3@sp2 nanocarbons, from this perspective, could enhance catalytic activity by tuning the electronic structure of the active sites. Herein, N-doped sp3@sp2 hybrids were prepared from nanodiamonds (NDs) and (NH4)2CO3 as starting N precursor to dope the NDs and tune their sp3/sp2. The N-doped sp3@sp2 hybrid nanocarbons were studied in the oxidative catalytic synthesis of a broad series of drug-related compounds (23 examples of 2-substituted benzoxazoles, benzothiazoles and benzimidazoles). These catalysts show high catalytic activity and reusability in mild conditions. Their performances are comparable to homogeneous/heterogeneous metal-based catalysts. The pyridinic N species determine the enhancement in the catalytic performance. The mechanistic results indicate that the N-doped sp3@sp2 hybrid activates oxygen molecules to form O2•- as reactive oxygen species, which abstracts the proton attached on the catalyst's surface. This study provides an attractive and useful methodology for applying ND-derived carbocatalysts to synthesise 2-substituted benzoxazoles and more complex drug targets.
DOI: 10.3389/fnut.2023.1171830
2023
Cited 5 times
Causal effect of vitamin D on myasthenia gravis: a two-sample Mendelian randomization study
Observational studies suggest that vitamin D supplementation may be effective in preventing myasthenia gravis (MG). However, the causal relationship between circulating vitamin D levels and MG remains unclear. This study aimed to examine the genetic causality of circulating vitamin D and MG using data from large population-based genome-wide association studies (GWAS).SNPs (single nucleotide polymorphisms) strongly associated with exposure were selected. Two-sample Mendelian Randomization (MR) was performed with inverse variance weighting (IVW), MR-Egger (Mendelian randomization-Egger), weight median and MR-PRESSO (Mendelian randomization pleiotropy residual sum and outlier) methods. Heterogeneity was tested via IVW and MR-Egger. Pleiotropy was tested using MR-Egger intercept test and MR-PRESSO method. MR-PRESSO was also used to detect outliers. Leave-one-out analysis was used to identify SNPs with potential effect. Reverse MR analysis was also performed.In IVW, circulating vitamin D levels had no causal effect on MG [OR = 0.91 (0.67-1.22), p = 0.532] and MG had no causal effect on circulating vitamin D [OR = 1.01 (099-1.02), p = 0.663]. No heterogeneity or pleiotropy was observed (p > 0.05). Other MR methods also agreed with IVW results.This study provides the causal relationship between genetically predicted circulating vitamin D levels and MG and provides new insights into the genetics of MG.
DOI: 10.1016/j.ejphar.2007.01.096
2007
Cited 52 times
Role of polyamines in myocardial ischemia/reperfusion injury and their interactions with nitric oxide
Polyamines (putrescine, spermidine, and spermine) are present in all higher eukaryotic cells and are essential for cell growth, differentiation and apoptosis. Sharing common precursor with polyamines, nitric oxide (NO) is associated with myocardial ischemia/reperfusion injury by the generation of peroxynitrite. Although polyamines have been implicated in tissue ischemia injury, their metabolism and interactions with NO in myocardial ischemia/reperfusion injury have not been fully understood. In our experiment, when Langendorff perfused rat hearts were subjected to 40 min ischemia without reperfusion, both ornithine decarboxylase (ODC) and Spermidine/spermine N(1)-acetyltransferase (SSAT) activities were up-regulated and putrescine accumulated. While after reperfusion, ODC activity decreased and SSAT activity increased, resulting in putrescine accumulation and decreased spermidine and spermine. Meanwhile NO content was increased. In addition, sodium nitroprusside (SNP, a NO donor) decreased ODC activity in cardiac tissue homogenate but increased SSAT activity in a dose-dependent manner. Pre-treatment of isolated heart with N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME, an inhibitor of NO synthase) increased ODC activity. Exogenous spermine (1 mM) administration prior to ischemia prevented spermine decrease, reduced cardiac myocyte necrosis and apoptosis, and promoted the recovery of cardiac function after ischemia/reperfusion. These results suggest that acute heart ischemia activates myocardial polyamine stress response characterized by increased ODC and SSAT activities and accumulation of putrescine. Ischemia/reperfusion disturbs polyamine metabolism, and the loss of spermine might be associated with NO increase and thereby influences myocardial cell viability. Exogenous spermine may protect the hearts from myocardial ischemia/reperfusion injury.
DOI: 10.1016/j.bbrc.2008.02.053
2008
Cited 45 times
Involvement of calcium-sensing receptor in cardiac hypertrophy-induced by angiotensinII through calcineurin pathway in cultured neonatal rat cardiomyocytes
Cardiac hypertrophy is a common pathological change accompanying cardiovascular disease. Recently, some evidence indicated that calcium-sensing receptor (CaSR) expressed in the cardiovascular tissue. However, the functional involvement of CaSR in cardiac hypertrophy remains unclear. Previous studies have shown that CaSR caused accumulation of inositol phosphate to increase the release of intracellular calcium. Moreover, Ca2+-dependent phosphatase calcineurin (CaN) played a vital role in the development of cardiac hypertrophy. Therefore, we investigated the expression of CaSR in cardiac hypertrophy-induced by angiotensin II (AngII) and the effects of CaSR activated by GdCl3 on the related signaling transduction pathways. The results showed that AngII induced cardiac hypertrophy and up-regulated the expression of CaSR, meanwhile increased the intracellular calcium concentration ([Ca2+]i) and activated CaN hypertrophic signaling pathway. Compared with AngII alone, the above changes were further obvious when adding GdCl3. But the effects of GdCl3 on the cardiac hypertrophy were attenuated by CsA, a specific inhibitor of CaN. In conclusion, these results suggest that CaSR is involved in cardiac hypertrophy-induced by AngII through CaN pathway in cultured neonatal rat cardiomyocytes.
DOI: 10.1016/j.ultrasmedbio.2009.09.007
2010
Cited 42 times
Hypocrellin B Enhances Ultrasound-Induced Cell Death of Nasopharyngeal Carcinoma Cells
Hypocrellin B, a natural pigment from a traditional Chinese herb, has been attracting extensive attention. The present study aims to investigate whether hypocrellin B can enhance cell death induced by ultrasound sonification on nasopharyngeal carcinoma cells in vitro. The sonodynamic action of hypocrellin B was investigated on nasopharyngeal carcinoma cell line CNE2 cells as tumor model cells. In the experiments, the hypocrellin B concentration was kept constant at 2.5 μM and the cells were subject to ultrasound exposure for 15 s at an intensity of 0.65 W/cm2. Cytotoxicity was investigated 24 h after ultrasound sonification. Apoptosis was evaluated using flow cytometry with annexin V-FITC and propidium iodine staining and nuclear staining with Hoechst 33258. Cell ultrastructure morphology was observed using transmission electron microscopy (TEM). No significant dark cytotoxicity of hypocrellin B in the CNE2 cells was observed at the concentration of 2.5 μM. The cell death rate induced by ultrasound sonification was significantly higher in the presence of hypocrellin B than in the absence of hypocrellin B. Flow cytometry showed that ultrasound exposure in the presence of hypocrellin B significantly increased the early and late apoptotic rate, 18.64% and 22.57%, respectively, compared with the controls. Nuclear condensation was observed in the nuclear staining and swollen mitochondria and more vacuolar and broken cell membrane were found in TEM after the treatment of hypocrellin B and ultrasound. Our findings demonstrated that the presence of hypocrellin B significantly enhanced the cytotoxicity of ultrasound radiation in CNE2 cells, suggesting that hypocrellin B is a novel sonosensitizer and hypocrellin B-mediated sonodynamic therapy is a potential therapeutic modality in the management of malignant tumors. (E-mail: [email protected] or [email protected])
DOI: 10.1016/j.toxlet.2010.08.021
2010
Cited 41 times
Angiotensin-(1–7) ameliorates myocardial remodeling and interstitial fibrosis in spontaneous hypertension: Role of MMPs/TIMPs
Angiotensin-(1–7) displays antihypertensive and antiproliferative properties although its effect on cardiac remodeling and hypertrophy in hypertension has not been fully elucidated. The present study was designed to examine the effect of chronic angiotensin-(1–7) treatment on myocardial remodeling, cardiac hypertrophy and underlying mechanisms in spontaneous hypertension. Adult male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were treated with or without angiotensin-(1–7) or the angiotensin-(1–7) antagonist A-779 for 24 weeks. Mean arterial pressure, left ventricular geometry, expression of the hypertrophic markers ANP and β-MHC, collagen contents (type I and III), collagenase (MMP-1), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of MMPs-1 (TIMP-1) were evaluated in WKY and SHR rats with or without treatment. Our data revealed that chronic angiotensin-(1–7) treatment significantly suppressed hypertension, left ventricular hypertrophy, expression of ANP and β-MHC as well as myocardial fibrosis in SHR rats, the effects of which were nullified by the angiotensin-(1–7) receptor antagonist A-779. In addition, angiotensin-(1–7) treatment significantly counteracted hypertension-induced changes in the mRNA expression of MMP-2 and TIMP-1 and collagenase activity, the effects of which were blunted by A-779. In vitro study revealed that angiotensin-(1–7) directly increased the activity of MMP-2 and MMP-9 while decreasing the content of TIMP-1 and TIMP-2. Taken together, our results revealed a protective effect of angiotensin-(1–7) against cardiac hypertrophy and collagen deposition, which may be related to concerted changes in MMPs and TIMPs levels. These data indicated the therapeutic potential of angiotensin-(1–7) in spontaneous hypertension-induced cardiac remodeling.
DOI: 10.1016/j.bbrc.2010.03.096
2010
Cited 41 times
Calcium-sensing receptor activation contributed to apoptosis stimulates TRPC6 channel in rat neonatal ventricular myocytes
Capacitative calcium entry (CCE) refers to the influx of calcium through plasma membrane channels activated on depletion of endoplasmic sarcoplasmic/reticulum (ER/SR) Ca2+ stores, which is performed mainly by the transient receptor potential (TRP) channels. TRP channels are expressed in cardiomyocytes. Calcium-sensing receptor (CaR) is also expressed in rat cardiac tissue and plays an important role in mediating cardiomyocyte apoptosis. However, there are no data regarding the link between CaR and TRP channels in rat heart. In this study, in rat neonatal myocytes, by Ca2+ imaging, we found that the depletion of ER/SR Ca2+ stores by thapsigargin (TG) elicited a transient rise in cytoplasmic Ca2+ ([Ca2+]i), followed by sustained increase depending on extracellular Ca2+. But, TRP channels inhibitor (SKF96365), not L-type channels or the Na+/Ca2+ exchanger inhibitors, inhibited [Ca2+]i relatively high. Then, we found that the stimulation of CaR with its activator gadolinium chloride (GdCl3) or by an increased extracellular Ca2+([Ca2+]o) increased the concentration of intracelluar Ca2+, whereas, the sustained elevation of [Ca2+]i was reduced in the presence of SKF96365. Similarly, the duration of [Ca2+]i increase was also shortened in the absence of extracellular Ca2+. Western blot analysis showed that GdCl3 increased the expression of TRPC6, which was reversed by SKF96365. Additionally, SKF96365 reduced cardiomyocyte apoptosis induced by GdCl3. Our results suggested that CCE exhibited in rat neonatal myocytes and CaR activation induced Ca2+-permeable cationic channels TRPCs to gate the CCE, for which TRPC6 was one of the most likely candidates. TRPC6 channel was functionally coupled with CaR to enhance the cardiomyocyte apoptosis.
DOI: 10.1111/j.1742-7843.2010.00639.x
2010
Cited 38 times
The Calcium-Sensing Receptor Mediates Hypoxia-Induced Proliferation of Rat Pulmonary Artery Smooth Muscle Cells Through MEK1/ERK1,2 and PI3K Pathways
Activation of the calcium-sensing receptor (CaSR) leads to an increase of intracellular calcium concentration and alteration of cellular activities. High level of intracellular calcium is involved in hypoxia-induced proliferation of pulmonary arterial smooth muscle cells (PASMCs). However, whether the CaSR is expressed in PAMSCs and is related to the hypoxia-induced proliferation of PASMCs is unclear. In this study, the expression and distribution of CaSRs were detected by RT-PCR, western blotting and immunofluorescence; the intracellular concentration of free calcium ([Ca(2+) ](i) ) was determined by confocal laser scanning microscopy; cell proliferation was tested using an MTT and BrdU incorporation assay; cell cycle analysis was carried out using a flow cytometric assay; and the expression of proliferating cell nuclear antigen (PCNA), extracellular signal-regulated protein kinase 1,2 (ERK1,2) and AKT were analysed by western blotting. We observed that both CaSR mRNA and protein were expressed in rat PASMCs. Lowering of oxygen from 21% to 2.5% led to increased [Ca(2+) ](i) and CaSR expression. This condition of hypoxia also stimulated PASMCs proliferation accompanying with increased phosphorylation of ERK1,2 and AKT. GdCl(3) (an agonist of CaSR) or NPS2390 (an antagonist of CaSR) amplified or weakened the effect of hypoxia, respectively. PD98059 (a MEK1 inhibitor) or LY294002 (a PI3K inhibitors) decreased the up-regulation of PCNA expression and the increase of the cell proliferation index induced by hypoxia and GdCl(3) in PASMCs. Our results suggest that CaSR is expressed in rat PASMCs, and that CaSR activation through MEK1/ERK1,2 and PI3 kinase pathways is involved in hypoxia-induced proliferation of PASMCs.
DOI: 10.1002/lapl.200910095
2010
Cited 38 times
Light-activated hypericin induces cellular destruction of nasopharyngeal carcinoma cells
Hypericin from Hypericum perforatum plants shows an important promise in the photodynamic therapy on malignant tumor. The present study investigated that light-activated hypericin induced the cellular destruction of nasopharyngeal carcinoma cells. The result showed that hypericin resulted in a drug- and light-dose dependent cytotoxicity in the CNE-2 cells, meaning the photocytotoxicity of hypericin depends on both of the drug concentration (0 – 2.5 μM) and light-doses (1 – 8 J/cm2). We further investigated the apoptosis of the CNE-2 cells 8 hours after photosensitization of hypericin using fluorescence microscopy with Hoechst 33258 staining. Flow cytometry with annexin V-FITC and PI staining was used to analyze early and late apoptosis. These data demonstrated that light-activated hypericin could significantly lead to the cellular destruction of the CNE-2 cells and induce early apoptosis as a prominent mode of cell death.
DOI: 10.1007/s00709-012-0386-6
2012
Cited 37 times
Organization of actin cytoskeleton during meiosis I in a wheat thermo-sensitive genic male sterile line
DOI: 10.1007/s11010-012-1312-0
2012
Cited 35 times
Increased expression of calcium-sensing receptors in atherosclerosis confers hypersensitivity to acute myocardial infarction in rats
DOI: 10.1007/s11010-012-1435-3
2012
Cited 34 times
Exogenous hydrogen sulfide attenuates diabetic myocardial injury through cardiac mitochondrial protection
DOI: 10.1016/j.diabres.2011.11.007
2012
Cited 34 times
Decrease in calcium-sensing receptor in the progress of diabetic cardiomyopathy
To observe the dynamic expression of calcium-sensing receptor (CaSR) in myocardium of diabetic rats and explore its role in diabetic cardiomyopathy (DCM), 40 male Wistar rats were randomly divided into 4 groups including control, diabetic-4 weeks, diabetic-8 weeks and spermine treatment groups (240 μM of spermine in drinking water). The type 2 Diabetes mellitus (DM) models were established by intraperitoneal injection of streptozotocin (STZ, 30 mg/kg) after high-fat and high-sugar diet for one month. The echocardiographic parameters were measured, cardiac morphology was observed by electron microscope and HE staining. The intracellular calcium concentration ([Ca2+]i) was detected by laser-scanning confocal microscope. Western blot analyzed the expression of CaSR, protein kinase C α(PKC-α) and calcium handling regulators, such as phospholamban (PLN), Ca2+-ATPase (SERCA), and ryanodine receptor (RyR). Compared with control group, [Ca2+]i and the expression of CaSR, RyR and SERCA/PLN were decreased, while PKC-α and PLN were significantly increased in a time-dependent manner in diabetic groups. Meanwhile diabetic rats displayed abnormal cardiac structure and systolic and diastolic dysfunction, and spermine (CaSR agonist) could prevent or slow its progression. These results indicate that the CaSR expression of myocardium is reduced in the progress of DCM, and its potential mechanism is related to the impaired intracellular calcium homeostasis.
DOI: 10.1007/s11010-014-2145-9
2014
Cited 34 times
Involvement of calcium-sensing receptors in hypoxia-induced vascular remodeling and pulmonary hypertension by promoting phenotypic modulation of small pulmonary arteries
DOI: 10.1155/2014/457429
2014
Cited 33 times
Exercise Training Preserves Ischemic Preconditioning in Aged Rat Hearts by Restoring the Myocardial Polyamine Pool
Ischemic preconditioning (IPC) strongly protects against myocardial ischemia reperfusion (IR) injury. However, IPC protection is ineffective in aged hearts. Exercise training reduces the incidence of age-related cardiovascular disease and upregulates the ornithine decarboxylase (ODC)/polyamine pathway. The aim of this study was to investigate whether exercise can reestablish IPC protection in aged hearts and whether IPC protection is linked to restoration of the cardiac polyamine pool.Rats aging 3 or 18 months perform treadmill exercises with or without gradient respectively for 6 weeks. Isolated hearts and isolated cardiomyocytes were exposed to an IR and IPC protocol.IPC induced an increase in myocardial polyamines by regulating ODC and spermidine/spermine acetyltransferase (SSAT) in young rat hearts, but IPC did not affect polyamine metabolism in aged hearts. Exercise training inhibited the loss of preconditioning protection and restored the polyamine pool by activating ODC and inhibiting SSAT in aged hearts. An ODC inhibitor, α-difluoromethylornithine, abolished the recovery of preconditioning protection mediated by exercise. Moreover, polyamines improved age-associated mitochondrial dysfunction in vitro.Exercise appears to restore preconditioning protection in aged rat hearts, possibly due to an increase in intracellular polyamines and an improvement in mitochondrial function in response to a preconditioning stimulus.
DOI: 10.3892/mmr.2015.3941
2015
Cited 32 times
Diagnostic and therapeutic research on ultrasound microbubble/nanobubble contrast agents (Review)
The contrast enhanced imaging function of ultrasound contrast agents (UCAs) has been extensively investigated using physical acoustic signatures. It has a number of novel applications, including tissue‑specific molecular imaging and multi‑modal imaging. In addition there are numerous other therapeutic applications of UCAs, for example as vehicles for drug or gene delivery. These uses are discussed, as well as the acoustically‑induced biological effects, including ultrasound targeted microbubble destruction (UTMD). This review also explores the considerations for the safe use of UCA from an acoustic standpoint. The scope of the application of UCA has markedly expanded in recent years, and it is a rapidly growing field of medical research. The current article reviews recent advances in the diagnostic and therapeutic applications of ultrasound microbubble/nanobubble contrast agents.
DOI: 10.1016/j.molimm.2014.08.007
2015
Cited 32 times
Calcium-sensing receptor in the T lymphocyte enhanced the apoptosis and cytokine secretion in sepsis
Calcium-sensing receptor (CaSR) is a member of the G protein-coupled receptor superfamily that existed in lymphocytes and promoted cytokine secretion. Lymphocytes are also involved in sepsis. However, the role of CaSR in lymphocytes in sepsis is unclear. In this study, we want to examine whether the CaSR in lymphocytes in sepsis is involved in the cytokine secretions and apoptosis and make clear the relationship between NF-κB and MAPK signal transduction pathways. We investigated the issues mentioned earlier using Western blotting, ELISA, and Flow Cytometry. The sepsis was remodeled by cecal ligation and puncture (CLP). We found that CaSR protein expression increased in the peripheral blood T lymphocytes in CLP rats. The calcimimetic R568 (NPS R568) promoted, whereas the calcilytic NPS 2143 attenuated, signaling pathways proteins P65 (subunit of NF-κB), ERK1/2, and JNK (one subgroup of MAPKs) phosphorylation. However, P-P38 and P-JAKs exhibit no significant changes. Furthermore, the production TNF-α and IL-4 was greater in CLP rats than in normal rats, and NPS R568 promoted secretion of these cytokines. Simultaneously, the apoptotic ratio of T cells in CLP increased, and NPS R 568 exacerbated the apoptosis degree. However, these effects could also be inhibited by U0126 or SP600125 (MAPKs pathway inhibitor) or Bay-11-7082 or (NF-κB pathway inhibitor). From these results, we can conclude that, in the sepsis, CaSR activation promoted T-cell apoptosis and the secretion of pro-inflammatory cytokine TNF-α and anti-inflammatory cytokines IL-4 probably through NF-κB and partial MAPK signal transduction pathways.