title: Epigallocatechin gallate (EGCG) prevents H2O2-induced oxidative stress in primary rat retinal pigment epithelial cells.
abstract: OBJECTIVE
  To determine whether the green tea polyphenol epigallocatechin gallate (EGCG) could prevent H(2)O(2)-induced oxidative stress in primary rat retinal pigment epithelial cells.
  
  
  METHODS
  Primary cultures of retinal pigment epithelium (RPE) cells were established from Long-Evans newborn rats. RPE cells were pretreated with various concentrations of EGCG for 24 h before being exposed to hydrogen peroxide (H(2)O(2)) for 2 h to induce oxidative stress. Cell metabolic activity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell death was quantified by flow cytometry using propidium iodide (PI).
  
  
  RESULTS
  Treatment of RPE cells with EGCG alone does not affect the cell viability up to 50 µM. Exposure of RPE cells to 600 µM H(2)O(2) caused a significant decrease in cell viability; whereas pretreatment with 10, 25, and 50 µM EGCG significantly reduced this decrease in a dose-dependent manner. The proportion of PI-positive cells increased significantly in cultures treated with H(2)O(2) alone; whereas pretreatment of RPE cells with 50 µM EGCG significantly reduced H(2)O(2)-induced RPE cell death.
  
  
  CONCLUSIONS
  Our study shows that EGCG pretreatment can protect primary rat RPE cells from H(2)O(2)-induced death. This suggests potential effect of EGCG in the prevention of retinal diseases associated with H(2)O(2)-induced oxidative stress.
authors.affiliation: UMR INSERM 1107, Equipe Biophysique Neurosensorielle, UFR Pharmacie, Clermont Université , Clermont-Ferrand , France and.
authors.forename: David
authors.initials: D
authors.lastname: Cia
authors.forename: Juliette
authors.initials: J
authors.lastname: Vergnaud-Gauduchon
authors.forename: Nathalie
authors.initials: N
authors.lastname: Jacquemot
authors.forename: Michel
authors.initials: M
authors.lastname: Doly
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006861:Hydrogen Peroxide / Q000633:toxicity*; D016877:Oxidants / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D020318:Rats, Long-Evans; D055213:Retinal Pigment Epithelium / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology
chemical_list: D000975:Antioxidants; D016877:Oxidants; D002392:Catechin; D006861:Hydrogen Peroxide; C045651:epigallocatechin gallate
keywords: Age-related macular degeneration; epigallocatechin gallate; hydrogen peroxide; oxidative stress; primary retinal pigment epithelial cell