Sal B Alleviates Myocardial Ischemic Injury by Inhibiting TLR4 and the Priming Phase of NLRP3 Inflammasome

Salvianolic acid B is one of the main water-soluble components of Salvia miltiorrhiza Bge. Many reports have shown that it has significant anti-myocardial ischemia effect. However, the underlying mechanism remains unclear. Our present study demonstrated that Sal B could alleviate myocardial ischemic injury by inhibiting the priming phase of NLRP3 inflammasome. In vivo, serum c-troponin I (cTn), lactate dehydrogenase (LDH) levels, the cardiac function and infract size were examined. We found that Sal B could notably reduce the myocardial ischemic injury caused by ligation of the left anterior descending coronary artery. In vitro, Sal B down-regulated the TLR4/NF-κB signaling cascades in lipopolysaccharide (LPS)-stimulated H9C2 cells. Furthermore, Sal B reduced the expression levels of IL-1β and NLRP3 inflammasome in a dose-dependent manner. In short, our study provided evidence that Sal B could attenuate myocardial ischemic injury via inhibition of TLR4/NF-κB/NLRP3 signaling pathway. And in an upstream level, MD-2 may be the potential target.