Gypenosides Protect Retinal Pigment Epithelium Cells From Oxidative Stress

Food Chem Toxicol. 2018 Feb;112:76-85. doi: 10.1016/j.fct.2017.12.037. Epub 2017 Dec 21.

Abstract

Oxidative stress plays a critical role in the pathogenesis of retinal degeneration. Gypenosides are the major functional components isolated from Gynostemma pentaphyllum. They have been shown to protect against oxidative stress and inflammation and have also demonstrated a protective effect on experimental optic neuritis. In order to determine the protective properties of gypenosides against oxidative stress in human retinal pigment epithelium (RPE) cells, ARPE-19 cells were treated with H2O2 or H2O2 plus gypenosides for 24 h. ARPE-19 cells co-treated with gypenosides had significantly increased cell viability and decreased cell death rate when compared to cells treated with H2O2 alone. The level of GSH, the activities of SOD and catalase, and the expression of NRF2 and antioxidant genes were notably decreased, while there were marked increases in ROS, MDA and pro-inflammatory cytokines in ARPE-19 cells exposed to H2O2; co-treatment with gypenosides significantly counteract these changes. Our study suggests that gypenosides protect RPE cells from oxidative damage and offer therapeutic potential for the treatment of retinal degeneration.

Keywords: ARPE-19; Cell death; Gypenosides; Inflammation; Oxidative stress.

MeSH terms

  • Antioxidants / metabolism
  • Catalase / metabolism
  • Cell Death / drug effects
  • Cell Line
  • Enzyme-Linked Immunosorbent Assay
  • Gene Expression Regulation / drug effects
  • Glutathione / metabolism
  • Gynostemma
  • Humans
  • Hydrogen Peroxide / pharmacology
  • In Situ Nick-End Labeling
  • Inflammation / genetics
  • Malondialdehyde / metabolism
  • NF-E2-Related Factor 2 / genetics
  • NF-E2-Related Factor 2 / metabolism
  • Oxidative Stress / drug effects*
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use
  • Reactive Oxygen Species / metabolism
  • Real-Time Polymerase Chain Reaction
  • Retinal Degeneration / drug therapy
  • Retinal Pigment Epithelium / cytology
  • Retinal Pigment Epithelium / drug effects*
  • Retinal Pigment Epithelium / metabolism
  • Signal Transduction
  • Superoxide Dismutase / metabolism
  • Up-Regulation / drug effects

Substances

  • Antioxidants
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Plant Extracts
  • Reactive Oxygen Species
  • gypenoside
  • Malondialdehyde
  • Hydrogen Peroxide
  • Catalase
  • Superoxide Dismutase
  • Glutathione