Astilbin protects diabetic rat heart against ischemia-reperfusion injury via blockade of HMGB1-dependent NF-κB signaling pathway

Astilbin, a flavonoid compound was isolated from the rhizome of Smilax china L In this study, we investigated the anti-myocardial ischemia and reperfusion (I/R) injury effect of Astilbin on diabetic rats in vivo and elucidated the potential mechanism in vitro. The results showed that Astilbin significantly attenuated hypoxia-induced cell injury in a concentration-dependent manner. Treatment of H9c2 cells with Astilbin at 15 mu M blocked nuclear factor kappaB (NF-kappa B) phosphorylation by blocking High-mobility group box protein 1 (HMGB1) expression. Treatment of diabetic rats with Astilbin by intravenous injection (i.v.) at a single dose of 50 mg/kg protected the rats from myocardial IIR injury as indicated by decreasing infarct volume, improving hemodynamics and reducing myocardial damage, and also lowered serum levels of pro-inflammatory factors, reduced HMGB1 and phosphorylated NF-kappa B expression in ischemic myocardial tissue from diabetic rats. Additionally, treatment of diabetic rats with Astilbin at dose of 50 mg/1