Abstract: Objective To investigate the therapy effect of fermented cordyceps powder on diabetic cardiomyopathy, and the effect on expressions of NLRP3, Caspase-1 and interleukin (IL)-1β in myocardium of diabetic rats. Methods A total of 45 male SD rats were randomly divided into normal control group (group CON), diabetes group (group DM) and fermented cordyceps powder administration group (group CS, 1 g·kg- 1·d- 1). Diabetes rat model was induced by tail vein injection with streptozotocin (45 mg/kg) in group DM and group CS. The rats in group CS were given fermented cordyceps powder solution by gavage at a single dose of 1 g·kg-1·d-1 for 18 weeks. Rats of group CON and group DM were given 0.9% NaCl in the same way. All rats were sacrificed after 18 weeks. The pathological changes in myocardium were observed by HE staining and electron microscope. The expression of NLRP3 in myocardium was detected by Western blotting. The expression levels of NLRP3, Caspase-1 and IL-1β in myocardium were detected by immunohistochemistry. Results (1) Myocardial necrosis and fibrosis and mitochondrial damages were observed under electron microscope in group DM. The above-mentioned pathological changes were improved in the group CS. (2) The result of Western blotting showed that the expression of NLRP3 in myocardium was significantly increased in group DM and group CS than that in group CON, and the expression of NLRP3 was significantly lower in group CS than that in group DM. (3) The result of immunohistochemistry showed that, compared with the group CON, the expressions of NLRP3, Caspase- 1 and IL- 1β in myocardium were significantly increased in group DM and group CS, and which were significantly lower in group CS than those in group DM. Conclusion Fermented cordyceps powder can improve diabetic cardiomyopathy through decreasing the expressions of NLRP3, Caspase-1 and IL-1β in myocardium.

Key words: diabetes complications, caspase- 1, interleukin- 1beta, diabetic cardiomyopathy, fermented cordyceps powder, NLRP3