Dioscin Derived from Solanum melongena L. "Usukawamarunasu" Attenuates α-MSH-Induced Melanogenesis in B16 Murine Melanoma Cells via Downregulation of Phospho-CREB and MITF

• Published in: Journal of food science Vol. 80; no. 10; pp. H2354 - H2359
• Main Authors: Nishina, Atsuyoshi, Ebina, Kodai, Ukiya, Motohiko, Fukatsu, Makoto, Koketsu, Mamoru, Ninomiya, Masayuki, Sato, Daisuke, Kimura, Hirokazu
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-10-2015
• Subjects: alpha-MSH - metabolism; Animals; Attenuation; Binding; cAMP-responsive element binding protein 1 transcription factors; Cyclic AMP Response Element-Binding Protein - metabolism; dioscin; Diosgenin - analogs & derivatives; Diosgenin - pharmacology; Down-Regulation - drug effects; Extracellular Signal-Regulated MAP Kinases - genetics; Hormones; Inhibition; Intramolecular Oxidoreductases - metabolism; Kinases; Melanins - biosynthesis; melanogenesis; Melanoma, Experimental - metabolism; Membrane Glycoproteins - metabolism; Mice; Microphthalmia-Associated Transcription Factor - metabolism; microphthalmia-related transcription factor; Monophenol Monooxygenase - metabolism; Oxidoreductases - metabolism; Phosphorylation; Plant Extracts - pharmacology; Reduction; Solanum melongena - chemistry; Solanum melongena L; Tyrosinase; melanogenesis; cAMP-responsive element binding protein 1 transcription factors; dioscin; Solanum melongena L; microphthalmia-related transcription factor
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/1750-3841.13068

This study aimed to chemically isolate and explore an antimelanogenesis inducer in extracts of Solanum melongena L. “Usukawamarunasu” eggplant. We successfully identified dioscin ([25R]‐Spirost‐5‐en‐3β‐yl) 2‐O‐(6‐deoxy‐α‐l‐mannopyranosyl) ‐ 4‐O‐(6‐deoxy‐α‐l‐mannopyranosyl)‐β‐d‐glucopyranoside] in the plant, and examined the effects of α‐melanocyte‐stimulating hormone (MSH)–induced melanogenesis in B16 murine melanoma cells by this plant‐derived dioscin. Immunoblot analysis suggested that dioscin reduced the expression of tyrosinase, tyrosinase‐related protein‐1 (TRP‐1), and TRP‐2, resulting in inhibition of intracellular production of melanin. In addition, dioscin caused reduction of phosphorylated cAMP‐responsive element binding protein 1 transcription factors (CREB), which led to a reduction of microphthalmia‐related transcription factor (MITF) in α‐MSH‐stimulated cells, but did not affect phosphorylation of extracellular signal‐regulated kinase. Furthermore, dioscin significantly downregulated the expression of tyrosinase, TRP‐1, and TRP‐2, which led to the reduction of α‐MSH–induced melanogenesis in B16 cells. These results suggest that dioscin may decrease the level of MITF via inhibition of phosphorylation of CREB in α‐MSH–induced melanogenesis in B16 cells.