Effect of Endoplasmic Reticulum Stress on Resveratrol-Induced Cardioprotection

Abstract

To investigate if resveratrol prevent the mitochondrial permeability transition pore (mPTP) opening through inhibition of endoplasmic reticulum stress (ERS). Methods: Rat heart tissue-derived cardiac H9c2 myoblast cell line was cultured. Fluorescence images of mitochondrial membrane potential were obtained with confocal microscopy. Western blotting analyzes the ERS marker protein GRP78 expression. Transmission electron microscopy detects the subcellular structure. Results: Exposure of cardiac H9c2 cells to 100 μM 2-DG, the ERS inducer, for 20 min caused a marked decrease in mitochondrial specific tetramethylrhodamine ethyl ester (TMRE) fluorescence. Resveratrol significantly prevented the loss of TMRE fluorescence. Western blotting revealed that resveratrol decreased GRP78 expression. Experiments with transmission electron microscopy revealed that resveratrol prevented 2-DG-induced swelling of endoplasmic reticulum and mitochondrial damages. Conclusions: These data suggest that inhibition of ERS leads to the prevention of mPTP opening. Resveratrol prevents the mPTP opening through inhibition of ERS.