The activation of PPARγ by 2,4,6-Octatrienoic acid protects human keratinocytes from UVR-induced damages

Sci Rep. 2017 Aug 23;7(1):9241. doi: 10.1038/s41598-017-09578-3.

Abstract

Increasing attention is addressed to identify products able to enhance skin photoprotection and to prevent skin carcinogenesis. Several studies have demonstrated that the α-melanocyte stimulating hormone (αMSH), acting on a functional MC1R, provides a photoprotective effect by inducing pigmentation, antioxidants and DNA repair. We discovered a link between αMSH and the nuclear receptor Peroxisome Proliferator-Activated Receptor-γ (PPARγ), suggesting that some of the αMSH protective effects may be dependent on PPARγ transcriptional activity. Moreover, we demonstrated that the activation of PPARγ by the parrodiene 2,4,6-octatrienoic acid (Octa) induces melanogenesis and antioxidant defence in human melanocytes and counteracts senescence-like phenotype in human fibroblasts. In this study, we demonstrate that the activation of PPARγ by Octa exerts a protective effect against UVA- and UVB-induced damage on normal human keratinocytes (NHKs), the major target cells of UV radiation. Octa promotes the antioxidant defence, augments DNA repair and reduces the induction of proteins involved in UV-induced DNA damage response. Our results contribute to deepen the analysis of the αMSH/PPARγ connection and suggest perspectives for the development of new molecules and formulations able to prevent cutaneous UV damage by acting on the different skin cell populations through PPARγ activation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antioxidants / metabolism
  • Cells, Cultured
  • DNA Damage / drug effects
  • DNA Damage / radiation effects
  • Enzyme Activation / drug effects
  • Fatty Acids, Unsaturated / pharmacology*
  • Gene Expression Regulation / drug effects
  • Humans
  • Keratinocytes / drug effects*
  • Keratinocytes / enzymology*
  • Keratinocytes / pathology
  • Keratinocytes / radiation effects*
  • PPAR gamma / agonists*
  • PPAR gamma / genetics
  • PPAR gamma / metabolism
  • Radiation-Protective Agents / pharmacology*
  • Receptor, Melanocortin, Type 1 / genetics
  • Receptor, Melanocortin, Type 1 / metabolism
  • Ultraviolet Rays / adverse effects*
  • alpha-MSH / metabolism

Substances

  • Antioxidants
  • Fatty Acids, Unsaturated
  • MC1R protein, human
  • PPAR gamma
  • Radiation-Protective Agents
  • Receptor, Melanocortin, Type 1
  • alpha-MSH
  • octa-2,4,6-trienoic acid