保元汤合苓桂术甘汤加减对心肌梗死后心衰大鼠心肌线粒体损伤及NLRP3/GSDMD介导的细胞焦亡的影响OA

Objective:To investigate the therapeutic effects of modified Baoyuantang combined with Linggui Zhugantang on post-myocardial infarction heart failure in rats and its influence on NOD-like receptor pyrin domain-containing protein 3(NLRP3)/gasdermin D(GSDMD)-mediated pyroptosis.Methods:Sixty male SD rats were randomized into sham,model,low-,medium-,and high-dose(2.52,5.04,10.08 g·kg-1,respectively)modified Baoyuantang combined with Linggui Zhugantang,and sacubitril/valsartan sodium(0.021 g·kg-1)groups,with 10 rats in each group.Except the sham group,the other groups underwent left anterior descending coronary artery ligation for the modeling of myocardial infarction.The treatment groups were administrated with corresponding drugs by gavage,and the sham and model groups received an equal volume of normal saline.Administration began on the first day after successful modeling,once daily,for 4 weeks.Echocardiography was used to measure left ventricular ejection fraction(LVEF),left ventricular fractional shortening(LVFS),left ventricular end-diastolic and end-systolic diameters(LVIDd and LVIDs),left ventricular posterior wall thicknesses at end-diastole and end-systole(LVPWd,LVPWs),and left ventricular volumes at end-diastole and end-systole(LV Vold and LV Vols).Cardiac mass index and heart weight-to-tibia length ratio were calculated.Hematoxylin-eosin(HE)staining and Sirius Red staining were performed to observe myocardial morphology and collagen deposition.Immunohistochemistry was employed to detect the expression of type Ⅰ collagen(Collagen Ⅰ),NLRP3,GSDMD,and interleukin-1β(IL-1β).Transmission electron microscopy was used to observe the mitochondrial ultrastructure.Tetramethylrhodamine methyl ester(TMRM)staining was conducted to assess mitochondrial membrane potential(MMP)in cardiomyocytes.Real-time PCR was used to quantify the mRNA levels of NLRP3,cysteinyl aspartate-specific proteinase-1(Caspase-1),IL-1β,GSDMD,and interleukin-18(IL-18)in the myocardial tissue.Western blotting was employed to determine the protein levels of NLRP3,Caspase-1,GSDMD,IL-1β,IL-18,nuclear factor kappa-B(NF-κB)p50,and NF-κB p65 in the myocardial tissue.Enzyme-linked immunosorbent assay(ELISA)was adopted to measure the serum levels of tumor necrosis factor-α(TNF-α),IL-1β,and IL-6.Results:Compared with the sham group,the model group showed increased LVIDd,LVIDs,LV Vold,LV Vols,cardiac mass index,and heart weight-to-tibia length ratio(P<0.05),decreased LVPWs,LVEF,LVFS,and MMP(P<0.05),evident myocardial inflammation,fibrosis,and mitochondrial damage,upregulated expression of NLRP3,Caspase-1,GSDMD,IL-1β,IL-18,NF-κB p50,and NF-κB p65,and elevated serum levels of TNF-α,IL-1β,and IL-6(P<0.05).Compared with the model group,modified Baoyuantang combined with Linggui Zhugantang reduced the LVIDd,LVIDs,LV Vols,cardiac mass index,and heart weight-to-tibia length ratio(P<0.05),increased the LVPWs,LVEF,LVFS,and MMP(P<0.05),alleviated myocardial inflammation and fibrosis,improved the mitochondrial structure and function,downregulated the expression of NLRP3,Caspase-1,GSDMD,IL-1β,IL-18,NF-κB p50,and NF-κB p65(P<0.05),and reduced the serum levels of TNF-α,IL-1β,and IL-6(P<0.05).Conclusion:Modified Baoyuantang combined with Linggui Zhugantang can ameliorate post-myocardial infarction ventricular remodeling and improve the cardiac function by reducing mitochondrial damage and inhibiting NLRP3/GSDMD-mediated pyroptosis.