Caffeic acid phenethyl ester inhibits alpha-melanocyte stimulating hormone-induced melanin synthesis through suppressing transactivation activity of microphthalmia-associated transcription factor

J Nat Prod. 2013 Aug 23;76(8):1399-405. doi: 10.1021/np400129z. Epub 2013 Jul 22.

Abstract

Caffeic acid phenethyl ester (1), a natural compound found in various plants and propolis, is a well-known anti-inflammatory, immunomodulatory, and cytotoxic agent. The present study aimed to investigate the molecular events underlying the antimelanogenic activity of 1 in alpha-melanocyte stimulating hormone (α-MSH)-stimulated B16-F10 melanoma cells. In this investigation, 1 effectively reduced α-MSH-stimulated melanin synthesis by suppressing expression of melanogenic enzymes such as tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2), although this compound did not directly inhibit tyrosinase enzyme activity. On the other hand, the expression and nuclear translocation of microphthalmia-associated transcription factor (MITF) as a key transcription factor for tyrosinase expression regulating melanogenesis were not affected by treatment with 1. The upstream signaling pathways including cAMP response element-binding protein (CREB), glycogen synthase kinase-3β (GSK-3β), and Akt for activation and expression of MITF were also not influenced by 1. Interestingly, 1 inhibited transcriptional activity of a tyrosinase promoter by suppressing the interaction of MITF protein with an M-box containing a CATGTG motif on the tyrosinase promoter. Given the important role of MITF in melanogenesis, suppression of 1 on the function of MITF to transactivate tyrosinase promoter may present a novel therapeutic approach to treat hyperpigmentation disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Caffeic Acids / pharmacology*
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • Glycogen Synthase Kinase 3 / metabolism
  • Glycogen Synthase Kinase 3 beta
  • Interferon Type I
  • Intramolecular Oxidoreductases / metabolism
  • Levodopa / metabolism
  • Melanins / biosynthesis
  • Melanins / metabolism
  • Mice
  • Microphthalmia-Associated Transcription Factor / genetics*
  • Microphthalmia-Associated Transcription Factor / metabolism
  • Molecular Structure
  • Monophenol Monooxygenase / metabolism
  • Oxidoreductases / metabolism*
  • Phenylethyl Alcohol / analogs & derivatives*
  • Phenylethyl Alcohol / pharmacology
  • Pregnancy Proteins
  • Transcriptional Activation
  • alpha-MSH / genetics
  • alpha-MSH / metabolism

Substances

  • Caffeic Acids
  • Cyclic AMP Response Element-Binding Protein
  • Interferon Type I
  • Melanins
  • Microphthalmia-Associated Transcription Factor
  • Pregnancy Proteins
  • interferon tau
  • Levodopa
  • alpha-MSH
  • Oxidoreductases
  • tyrosinase-related protein-1
  • Monophenol Monooxygenase
  • Glycogen Synthase Kinase 3 beta
  • Gsk3b protein, mouse
  • Glycogen Synthase Kinase 3
  • Intramolecular Oxidoreductases
  • dopachrome isomerase
  • caffeic acid phenethyl ester
  • Phenylethyl Alcohol