Blockade of store-operated calcium entry alleviates ethanol-induced hepatotoxicity via inhibiting apoptosis

Extracellular Ca2+ influx has been suggested to play a role in ethanol-induced hepatocyte apoptosis and necrosis. Previous studies indicated that store-operated Ca2+ entry (SOCE) was involved in liver injury induced by ethanol in HepG2 cells. However, the mechanisms underlying liver injury caused by SOCE remain unclear. We aimed to investigate the effects and mechanism of SOCE inhibition on liver injury induced by ethanol in BRL cells and Sprague–Dawley rats. Our data demonstrated that ethanol (0–400mM) dose-dependently increased hepatocyte injury and 100mM ethanol significantly upregulated the mRNA and protein expression of SOC for at least 72h in BRL cells. Blockade of SOCE by pharmacological inhibitors and sh-RNA knockdown of STIM1 and Orai1 attenuated intracellular Ca2+ overload, restored the mitochondrial membrane potential (MMP), decreased cytochrome C release and inhibited ethanol-induced apoptosis. STIM1 and Orai1 expression was greater in ethanol-treated than control rats, and the SOCE inhibitor corosolic acid ameliorated the histopathological findings and alanine transaminase and aspartate transaminase activity as well as decreased cytochrome C release and inhibited alcohol-induced cell apoptosis. These findings suggest that SOCE blockade could alleviate alcohol-induced hepatotoxicity via inhibiting apoptosis. SOCE might be a useful therapeutic target in alcoholic liver diseases.