title: Hot-water extracts from adzuki beans (Vigna angularis) stimulate not only melanogenesis in cultured mouse B16 melanoma cells but also pigmentation of hair color in C3H mice.
abstract: A hot-water extract of adzuki was obtained by boiling beans of adzuki (Vigna angularis). This hot-water extract was fractionated using HP-20 column chromatography. Its distilled water fraction (WEx) was found to stimulate tyrosinase activity in cultured mouse B16 melanoma cells and hair color pigmentation in C3H mice. At concentrations of 1-3 mg/ml, WEx stimulated melanogenesis without inhibiting cell growth. During this effect, WEx activated tyrosinase-inducing activity in the cells, but did not activate tyrosinase, which exists at an intracellular level. In this study, WEx increased cyclic adenosine-3',5'-monophospate (cAMP) content in the cells and protein kinase A (PKA) activity, and stimulated translocation of cytosolic protein kinase C (PKC) to the membrane-bound PKC. These results suggest that the addition of WEx activates the adenylcyclase and protein kinase pathways and, as a result, stimulates melanogenesis. WEx was found to have pigmentation activity on hair color in C3H mice. It might be useful in anti-graying, protecting human skin from irradiation.
authors.affiliation: Imuraya Confectionary Co., Ltd., Mie, Japan. chuken@imuraya.co.jp
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Itoh
authors.forename: Yukio
authors.initials: Y
authors.lastname: Furuichi
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae / Q000737:chemistry*; D006200:Hair Color / Q000187:drug effects*; D008543:Melanins / Q000096:biosynthesis*; D008546:Melanoma, Experimental / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology
chemical_list: D008543:Melanins; D010936:Plant Extracts