Protective effect of resveratrol on rat cardiomyocyte H9C2 cells injured by hypoxia/reoxygenation by regulating mitochondrial autophagy PTEN-induced putative kinase protein 1/Parkinson disease protein 2 signaling pathway.

Objective: To investigate the protective effect of resveratrol on cardiomyocytes after hypoxia/ reoxygenation intervention based on PTEN-induced putative kinase protein 1/Parkinson disease protein 2 (PINK1/PARKIN) signaling pathway.

Methods: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenylte-trazolium bromide was used to detect the effect of resveratrol on the viability of H9C2 cells; the hypoxia/ reoxygenation (H/R) model was established in tri-gas incubator; 2', 7'-Dichlorofluorescin diacetate staining was used to measure the content of reactive oxygen species (ROS); the changes of mitochondrial membrane potential was determined by 5,5',6,6'-Tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide staining; the changes of mitochondrial respiratory chain complex activity was evaluated by enzyme activity kits; flow cytometry was used to detect the ratio of apoptotic cells; transmission electron microscope was used to observe the ultrastructure of H9C2 cells; Western blot was used to detect the protein changes of mitochondrial 20 kDa outer membrane protein (TOM20), translocase of inner mitochondrial membrane 23 (TIM23), presenilins associated rhomboid-like protein (PARL), PINK1, PARKIN and mitofusin 1 (Mfn1), mitofusin 2 (Mfn2), phosphotyrosine independent ligand for the Lck SH2 domain of 62 kDa (P62), microtubule-associated protein 1 light chain 3 beta (LC3B); the mRNA levels of PINK1 and PARKIN was detected by quantitative polymerase chain reaction; immunoprecipitation assay was used to detect the interaction between PARKIN and Ubiquitin.

Results: Resveratrol could inhibit the proliferation of H9C2 cells in a time- and concentration- dependent manner; however, pretreatment with low cytotoxic resveratrol could reduce the H/R-induced increase in cellular ROS levels, alleviate the loss of mitochondrial membrane potential induced by H/R, inhibit H/R-induced apoptosis of H9C2 cells, and protect the mitochondrial structure and respiratory chain of H9C2 cells from H/R damage. Resveratrol could further increase the levels of p62, PINK1, PARKIN protein, the expression of PINK1, PARKIN mRNA and the ratio of LC3BⅡ/LC3BⅠin H/R-induced H9C2 cells, inhibit the interaction between PARKIN and Ubiquitin in H/R-induced H9C2 cells, and further reduce the expression of TOM20,TIM23, PARL, Mfn1 and Mfn2 protein in H/R-induced H9C2 cells. The effect of resveratrol is consistent with that of autophagy activator on H/R-induced H9C2 cells.

Conclusions: Resveratrol can protect H9C2 cells from H/R injury, which may be related to resveratrol promoting mitochondrial autophagy by activating PINK1/PARKIN signaling pathway.