Resveratrol Differentially Interacts with Oxidants to Protect against Oxidant-induced Stress in Human RPE cells

Abstract

Purpose : Age-related macular degeneration (AMD) is associated with loss of retinal pigment epithelial (RPE) cell function, in part related to oxidative stress. Although several different oxidants are used to model AMD, many studies often rely upon a single oxidant to induce RPE cell injury and do not account for oxidant effect variation. Previously, we reported that resveratrol (Res) protected against hydroquinone (HQ)-induced damage in RPE cells. Herein, we investigated how HQ, hydrogen peroxide (H₂O₂), and tert-butyl hydroperoxide (t-BHP) in the presence or absence of (Res) affect Akt, MAP Kinases (MAPKs) signaling, and downstream actin cytoskeleton dynamics in human RPE cells.

Methods : Cultured human RPE cells were treated with HQ (125-150μM), H₂O₂ (700μM), or t-BHP (500μM) in the presence or absence of Res (30μM) for various times. Akt, Erk1/2, and p38 protein phosphorylation levels were evaluated by Western blot. HQ-induced F-actin aggregate formation was evaluated with immunohistochemical staining and quantified using Image J Fiji software.

Results : HQ, H₂O₂, and t-BHP in the presence or absence of Res had varying effects on Akt, Erk1/2, and p38 phosphorylation (Table 1). F-actin aggregation was significantly increased by HQ (P<0.01) and significantly reduced in the presence of Res (P<0.01).

Conclusions : RPE cell stress induced by HQ, H₂O₂, and t-BHP elicited varied Akt and MAPKs responses. Res demonstrated protection in a mechanistically complex manner, suggesting different targets to therapeutically treat the pathogenesis of AMD depending upon the type of RPE cell injury.

This is a 2020 ARVO Annual Meeting abstract.

 

Effects on Akt, Erk1/2, and p38 phosphorylation after HQ(150μM), H₂O₂(700μM), or t-BHP(500μM) +/- Res(30μM) treatments for 1 hour.