The Protective Effect of a Metallic Selenopeptide with Superoxide Dismutase and Glutathione Peroxidase Activities Against Alcohol Induced Injury in Hepatic L02 Cells

A 65-mer peptide (Se-CuZn-65P) is an enzyme mimic with antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPX). The metallic selenopeptide imitate was obtained through a single protein production system and cysteine auxotrophic expression technique, and it enters cells in the assistance of the trans-activator of transcription peptide. Because Se-CuZn-65P was provided with the antioxidant activities of SOD and GPX, it can be a potential drug for the prevention of alcoholic liver diseases. Therefore, the protective effects of Se-CuZn-65P on ethanol-induced L02 cells were evaluated in vitro. Our results revealed that Se-CuZn-65P significantly protected the hepatocytes against ethanol-induced cell cytotoxicity which displayed by increase of cell viability, migration and decrease of reactive oxygen species (ROS), malondialdehyde (MDA), lactate dehydrogenase (LDH), aspartate aminotransferase (AST). Furthermore, the experiments of TUNEL assay, flow cytometry assay, expression levels determination of apoptosis-related gene (Bad, Bax, Bcl-xL, Bcl-2) and protein (pro-caspase3, PARP cleavage) indicated that Se-CuZn-65P inhibited ethanol-induced L02 cell apoptosis. Mechanically, Se-CuZn-65P could attenuate the oxidative damage of mitochondria in ethanol-induced L02 cells. Se-CuZn-65P prevented ethanol-triggered ROS and MDA generation in L02 cells and inhibited the release of the AST and LDH. Se-CuZn-65P also restored the equilibrium of proapoptotic and antiapoptotic genes including Bad, Bax, Bcl-xL, and Bcl-2. And the reduction of procaspase-3 and the cleavages of PARP were attenuated by Se-CuZn-65P. Thereby, the L02 cell apoptosis were significantly prevented by treatment with Se-CuZn-65P, mainly due to attenuation of oxidative stress. In summary, Se-CuZn-65P could prevent ethanol-induced liver injury through enhancing hepatocyte antioxidant abilities in intracellular.