Effects of baicalin against UVA-induced photoaging in skin fibroblasts

Am J Chin Med. 2014;42(3):709-27. doi: 10.1142/S0192415X14500463.

Abstract

Ultraviolet A (UVA) radiation contributes to skin photoaging. Baicalin, a plant-derived flavonoid, effectively absorbs UV rays and has been shown to have anti-oxidant and anti-inflammatory properties that may delay the photoaging process. In the current study, cultured human skin fibroblasts were incubated with 50 μg/ml baicalin 24 hours prior to 10 J/cm(2) UVA irradiation. In order to examine the efficacy of baicalin treatment in delaying UVA-induced photoaging, we investigated aging-related markers, cell cycle changes, anti-oxidant activity, telomere length, and DNA damage markers. UVA radiation caused an increased proportion of β-Gal positive cells and reduced telomere length in human skin fibroblasts. In addition, UVA radiation inhibited TGF-β1 secretion, induced G1 phase arrest, reduced SOD and GSH-Px levels, increased MDA levels, enhanced the expression of MMP-1, TIMP-1, p66, p53, and p16 mRNA, reduced c-myc mRNA expression, elevated p53 and p16 protein expression, and reduced c-myc protein expression. Baicalin treatment effectively protected human fibroblasts from these UVA radiation-induced aging responses, suggesting that the underlying mechanism involves the inhibition of oxidative damage and regulation of the expression of senescence-related genes, including those encoding for p53, p66(Shc) and p16.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents, Non-Steroidal
  • Antioxidants
  • Cell Cycle / drug effects
  • Cells, Cultured
  • Cellular Senescence / genetics*
  • Cellular Senescence / radiation effects*
  • Cyclin-Dependent Kinase Inhibitor p16
  • DNA Damage / drug effects
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • Fibroblasts / radiation effects*
  • Flavonoids / pharmacology*
  • Gene Expression / drug effects
  • Gene Expression / radiation effects
  • Humans
  • Neoplasm Proteins / metabolism
  • Shc Signaling Adaptor Proteins / metabolism
  • Skin / cytology*
  • Skin / radiation effects*
  • Skin Aging / genetics*
  • Skin Aging / radiation effects*
  • Src Homology 2 Domain-Containing, Transforming Protein 1
  • Telomere Homeostasis / drug effects
  • Transforming Growth Factor beta1 / metabolism
  • Tumor Suppressor Protein p53 / metabolism
  • Ultraviolet Rays / adverse effects*

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • Antioxidants
  • CDKN2A protein, human
  • Cyclin-Dependent Kinase Inhibitor p16
  • Flavonoids
  • Neoplasm Proteins
  • SHC1 protein, human
  • Shc Signaling Adaptor Proteins
  • Src Homology 2 Domain-Containing, Transforming Protein 1
  • Transforming Growth Factor beta1
  • Tumor Suppressor Protein p53
  • baicalin