title: Hypopigmentary effects of ethyl P-methoxycinnamate isolated from Kaempferia galanga.
abstract: We isolated crystals from the chloroform fraction of an ethanol extract of Kaempferia galanga and identified it as ethyl p-methoxycinnamate through nuclear magnetic resonance analysis. In the present study, we found that ethyl p-methoxycinnamate significantly decreased melanin synthesis in B16F10 murine melanoma cells stimulated with α-melanocyte stimulating hormone (α-MSH). In a cell-free system, however, ethyl p-methoxycinnamate did not directly inhibit tyrosinase, the rate-limiting enzyme of melanogenesis. Instead, it inhibited tyrosinase activity in B16F10 cells in a dose-dependent manner. Furthermore, Western blot analysis showed that ethyl p-methoxycinnamate decreased microphthalmia-associated transcription factor and tyrosinase levels in α-MSH-stimulated B16F10 cells. These results indicate that the pigment-inhibitory effect of ethyl p-methoxycinnamate results from downregulation of tyrosinase. Ethyl p-methoxycinnamate isolated from K. galanga could be developed as a skin whitening agent to treat hyperpigmentary disorders.
authors.affiliation: Department of Biochemistry, Chung-Ang University College of Medicine, 221 Heukseok-dong, Dongjak-gu, Seoul, 156-756, Korea.
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Ko
authors.forename: Hae Jong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Su Yeon
authors.initials: SY
authors.lastname: Kim
authors.forename: Hye-Young
authors.initials: HY
authors.lastname: Yun
authors.forename: Kwang Jin
authors.initials: KJ
authors.lastname: Baek
authors.forename: Nyoun Soo
authors.initials: NS
authors.lastname: Kwon
authors.lastname: Wan Kyun Whang
authors.forename: Hye-Ryung
authors.initials: HR
authors.lastname: Choi
authors.forename: Kyoung-Chan
authors.initials: KC
authors.lastname: Park
authors.forename: Dong-Seok
authors.initials: DS
authors.lastname: Kim
mesh_terms: D000818:Animals; D057886:Bleaching Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D002474:Cell-Free System; D002934:Cinnamates / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects* / Q000378:metabolism; D008546:Melanoma, Experimental / Q000378:metabolism; D051379:Mice; D051739:Microphthalmia-Associated Transcription Factor / Q000235:genetics / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D030521:Zingiberaceae / Q000737:chemistry*; D000521:alpha-MSH
chemical_list: D057886:Bleaching Agents; D002934:Cinnamates; D008543:Melanins; D051739:Microphthalmia-Associated Transcription Factor; D010936:Plant Extracts; C531364:ethyl 4-methoxycinnamate; D000521:alpha-MSH; D014442:Monophenol Monooxygenase
keywords: Kaempferia galanga; ethyl p-methoxycinnamate; melanin; skin whitening