Rutin alleviates hypoxia/reoxygenation-induced injury in myocardial cells by up-regulating SIRT1 expression

Rutin possesses multiple pharmacological activities, including the cardioprotective effect. The present study aimed to evaluate the protective effects of rutin on hypoxia/reoxygenation (H/R)-induced myocardial injury and its underlying mechanism involved. H9c2 cells were pretreated with 50 μM rutin or combined with 1 μM silent information regulator 1 (SIRT1) inhibitor (EX-527) for 1 h, and subjected to hypoxia for 6 h, followed by reoxygenation for 24 h. SIRT1 expression was detected by qRT-PCR and western blot. The effects of rutin or combined with EX-527 on cell viability, myocardial injury, apoptotic rate, and oxidative stress in H/R-stimulated H9c2 cells were assayed. The results showed that rutin elevated SIRT1 expression in H9c2 cells, as well as H/R-stimulated H9c2 cells. Rutin increased cell viability in H9c2 cells exposed to H/R. H/R stimulation induced myocardial injury, as evidenced by the increased levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and aspartate transaminase (AST), which were abolished in the presence of rutin. Rutin attenuated H/R-induced increase of apoptotic rate and caspase-3 activity in H/R-treated cells. Moreover, H/R-induced decrease in the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), and increase in malondialdehyde (MDA) content were reversed by rutin treatment. The presence of EX-527 abolished these protective effects of rutin. In conclusion, rutin protected H9c2 cells against H/R injury through increasing SIRT1 expression. Our findings suggested that rutin might be a potential therapeutic agent for the treatment of myocardial H/R injury.