title: Melanogenesis-inhibitory activity of aromatic glycosides from the stem bark of Acer buergerianum.
abstract: A new benzyl glucoside, 3-O-demethylnikoenoside (1), along with eleven known compounds, including seven aromatic glycosides, 2-8, three lignans, 9-11, and one cyclitol, 12, were isolated from the BuOH-soluble fraction of a MeOH extract of Acer buergerianum stem bark. The structures of the new compound were elucidated on the basis of extensive spectroscopic analyses and comparison with literature. Upon evaluation of compounds 1-12 on melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), three compounds, i.e., hovetrichoside B (8), pinoresinol 4-O-β-D-glucopyranoside (9), and pinoresinol 4-O-β-D-apiofuranosyl-(1→2)-β-D-glucopyranoside (10), have been found to exhibit inhibitory effects with 41-49% melanin content compared to the control at 100 μM and low cytotoxicity to the cells (81-92% cell viability at 100 μM). Western blot analysis showed that compound 8 reduced the protein levels of MITF (=microphtalmia-associated transcription factor) and tyrosinase, in a concentration-dependent manner, suggesting that 8 inhibits melanogenesis in α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase. On the other hand, upon Western blotting, compound 9 was found to reduce the protein levels of tyrosinase and TRP-2, while it increased MITF and TRP-1 (=tyrosine-related protein 1), in a concentration-dependent manner, indicating that 9 inhibits melanogenesis in α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of tyrosinase and TRP-2.
authors: College of Science and Technology, Nihon University, 1-8-14 Kanda Surugadai, Tokyo 101-8308, Japan. akihisa.toshihiro@nihon-u.ac.jp
authors: Toshihiro
authors: T
authors: Akihisa
authors: Masashi
authors: M
authors: Orido
authors: Hiroyuki
authors: H
authors: Akazawa
authors: Akitomo
authors: A
authors: Takahashi
authors: Ayako
authors: A
authors: Yamamoto
authors: Eri
authors: E
authors: Ogihara
authors: Makoto
authors: M
authors: Fukatsu
mesh_terms: D031002:Acer / Q000737:chemistry*; D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D008543:Melanins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008546:Melanoma, Experimental / Q000188:drug therapy / Q000378:metabolism*; D051379:Mice; D051739:Microphthalmia-Associated Transcription Factor / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000378:metabolism; D024301:Plant Bark / Q000737:chemistry*; D000521:alpha-MSH / Q000378:metabolism
chemical_list: D006027:Glycosides; D008543:Melanins; D051739:Microphthalmia-Associated Transcription Factor; D000521:alpha-MSH; D014442:Monophenol Monooxygenase