Inhibition of melanogenesis by jineol from Scolopendra subspinipes mutilans via MAP-Kinase mediated MITF downregulation and the proteasomal degradation of tyrosinase

Sci Rep. 2017 Apr 10:7:45858. doi: 10.1038/srep45858.

Abstract

In this study, the authors investigated the anti-melanogenic effects of 3,8-dihydroxyquinoline (jineol) isolated from Scolopendra subspinipes mutilans, the mechanisms responsible for its inhibition of melanogenesis in melan-a cells, and its antioxidant efficacy. Mushroom tyrosinase activities and melanin contents were determined in melan-a cells, and the protein and mRNA levels of MITF, tyrosinase, TYRP-1, and TYRP-2 were assessed. Jineol exhibited significant, concentration-dependent antioxidant effects as determined by DPPH, ABTS, CUPRAC, and FRAP assays. Jineol significantly inhibited mushroom tyrosinase activity by functioning as an uncompetitive inhibitor, and markedly inhibited melanin production and intracellular tyrosinase activity in melan-a cells. In addition, jineol abolished the expressions of tyrosinase, TYRP-1, TYRP-2, and MITF, thereby blocking melanin production and interfering with the phosphorylations of ERK1/2 and p38. Furthermore, specific inhibitors of ERK1/2 and p38 prevented melanogenesis inhibition by jineol, and the proteasome inhibitor (MG-132) prevented jineol-induced reductions in cellular tyrosinase levels. Taken together, jineol was found to stimulate MAP-kinase (ERK1/2 and p38) phosphorylation and the proteolytic degradation pathway, which led to the degradations of MITF and tyrosinase, and to suppress the productions of melanin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arthropods / genetics
  • Arthropods / metabolism
  • Gene Expression Regulation / drug effects
  • Melanins / biosynthesis
  • Melanins / genetics*
  • Melanocytes
  • Mice
  • Microphthalmia-Associated Transcription Factor / genetics*
  • Mitogen-Activated Protein Kinases / genetics
  • Monophenol Monooxygenase / chemistry
  • Monophenol Monooxygenase / genetics*
  • Phosphorylation / drug effects
  • Proteasome Endopeptidase Complex / drug effects
  • Proteolysis / drug effects
  • Signal Transduction / drug effects

Substances

  • Melanins
  • Microphthalmia-Associated Transcription Factor
  • Monophenol Monooxygenase
  • Mitogen-Activated Protein Kinases
  • Proteasome Endopeptidase Complex