Effects Of Sanguis Draconis Flavones On Myocardial Pyroptosis And Expression Of NLRP3 Inflammasome In Rats With Myocardial Ischemia-reperfusion Injury

Objective: To investigate the effects of Sanguis Draconis flavones(SDF)on myocardial pyroptosis and expression of NLRP3 inflammasome in rats with myocardial ischemia-reperfusion injuryMethods: A total of 60 SD rats were randomly divided into 6 groups: Normal group,Sham operation group,MIRI model group and low-dose,medium-dose and high-dose intervention groups of sanguis draconis flavones with 10 rats in each group.The doses of SDF were 90mg·kg-1,180mg·kg-1 and 360mg·kg-1,respectively.After 14 days of continuous intragastric administration,the rat model of myocardial ischemia reperfusion was established after the last administration.Serum Creatine kinase-MB(CK-MB)and Lactate Dehydrogenase(LDH)were detected by automatic biochemical analyzer.Pathological characteristics of myocardial injury were observed by hematoxylin-eosin(HE)staining.Myocardial infarct size was measured by TTC staining.The pyroptosis rate of cardiomyocytes were determined using Nucleotidyl transferase mediated Nick end labeling(TUNEL).The m RNA expressions of NLRP3,Caspase-1,apoptosis-associated speck-like protein containing a CARD(ASC)and interleukin-1β(IL-1β)in myocardial tissue were detected by Real-time Fluorescent Quantitative Polymerase Chain Reaction(q-PCR).Results: Compared with the Normal group and Sham group,the contents of CK-MB and LDH,myocardial infarction area,pyroptosis rate of myocardial cells,m RNA expression levels of NLRP3,ASC,Caspase-1 and IL-1β in the MIRI group were significantly increased(P < 0.01).Compared with MIRI model group,the contents of CK-MB and LDH,myocardial infarction area,pyroptosis rate of myocardial cells,m RNA expression levels of NLRP3,ASC,Caspase-1 and IL-1β in SDF intervention groups with different doses were significantly decreased(P < 0.05 or P < 0.01).The results of HE staining showed that SDF could significantly improve the pathological damage of myocardial tissue caused by reperfusion injury in rats,and the effect was more obvious in the medium-dose and high-dose groups.Conclusion: SDF can significantly reduce myocardial pathological injury and inflammation,myocardial infarction and pyroptosis,and thus exert an effective protective effect against MIRI,which may be related to the inhibition of myocardial cell pyrotosis and the expression of NLRP3 inflammasome.