Anthocyanins from Black Soybean Seed Coats Inhibit UVB-Induced Inflammatory Cylooxygenase-2 Gene Expression and PGE₂ Production through Regulation of the Nuclear Factor-κB and Phosphatidylinositol 3-Kinase/Akt Pathway

Ultraviolet (UV) radiation can cause inflammatory changes and may further contribute to skin carcinogenesis. Anthocyanins are known to be powerful antioxidants that help protect plants from UV damage. Recently, we isolated anthocyanins from black soybean [Glycine max (L.) Merr] seed coats. Thus, we investigated the protective effect of anthocyanins from black soybean seed coats on UVB radiation-induced inflammatory responses and the molecular mechanism responsible for regulation of apoptosis and inflammatory responses. Anthocyanins inhibited UVB-induced cylooxygenase-2 (COX-2) and PGE 2 production through a nuclear factor-kappaB-dependent pathway and regulation of the PI3 kinase/Akt pathway activated by UVB in a human keratinocyte cell line, HaCaT. Topical application of anthocyanins prior to UVB irradiation of hairless mice also inhibited induction of COX-2 and PGE 2. In conclusion, it is suggested that anthocyanins from the seed coat of black soybeans can be used as a useful drug to modulate oxidative disorders including UVB-induced inflammation.