Effect of Xinjikang on signaling pathway and apoptosis of myocardial Toll-like receptor 4-nuclear factor-κB in rats with viral myocarditis

Objective To determine the effect of Xinjikang on signaling pathway and apoptosis of Toll-like receptors 4 (TLR4) -nuclear factor-κB (TLR4-NF-κB) in rats with viral myocarditis (VMC) . Methods Eighty 3-month-old male rats were randomly divided into the model group (n=30) , Xinjikang group (n=30) and normal control group (n=20) . The model group receieved intraperitoneal injection of Coxsackievirus B3 (CVB3) . In addition, the Xinjikang group was injected with Xinjikang decoction (15 g/kg) . The normal group was inoculated intraperitoneally with 0.2 ml virus-free Eagle’s solution. The cardiac index (body weight/cardiac weight) in each group was statistically analyzed. The pathological changes of heart tissues were examined by HE staining. The expression levels of TLR-4 and NF-κB in myocardial tissues were determined by immunohistochemistry. The protein expression levels of TLR-4 and NF-κB in myocardial tissues were determined by Western Blotting. The myocardial cell apoptosis index (AI) was examined by in situ end labeling (TUNEL) method. Results (1) The mortality in the Xinjikang group was significantly lower than that in the model group, whereas the median survival time was significantly longer than that in the model group (P Xinjikang group>normal control group (P Xinjikang group>normal control group (P<0.05) . Conclusion Xinjikang may reduce the mortality of VMC rats, prolong the median survival time, inhibit the expression of TLR4 and NF-κB, and improve the myocardial cell apoptosis. Key words: Myocarditis; TLR4; NF-κB; Apoptosis