Effect of Gualou Xiebai Banxia Tang on Regulating TGF-β1/Smads Signaling Pathway on the Extracellular Matrix Remodeling in Myocardial Ischemia Model Rats

NIU Yun; TAN Yingying; ZHANG Qi

Abstract：Objective To observe the effect of Gualou Xiebai Banxia Tang on the pathological changes of myocardial tissue in rats with myocardial ischemia,and the intervention effect of Gualou Xiebai Banxia Tang on myocardial ECM remodeling.Methods Ten of the 70 SD rats were randomly selected as the control group.After successful modeling,the remaining rats were randomly divided into model group,Gualou Xiebai Banxia Tang low,medium and high dose group and metoprolol group.The treatment continued for 28 days.After the intervention,HE and Masson staining were used to observe the pathological changes and fibrosis degree of myocardial tissue in rats.The positive expression level of α-smooth muscle actin(α-SMA)was detected by immunohistochemistry.The contents of serum creatine kinase(CK),creatine kinase isoenzyme(CK-MB)and lactic dehydrogenase(LDH)were determined by colorimetry.The levels of N-terminal pro-B-type natriuretic peptide(NT-proBNP)and transforming growth factor(TGF)-β1 were detected by ELISA.The relative expression levels of TGF-β1,Smad2 and Smad3 proteins in myocardial tissue were detected by western blot.The expression levels of COL1A1 and FN mRNA were detected by RT-qPCR.Results Compared with the model group,the myocardial histopathology of the high-dose Gualou Xiebai Banxia Tang group showed different degrees of improvement,the myocardial fibers were arranged in an orderly manner,the cell boundaries were clear,there was still a slight widening of the gap,accompanied by a small amount of inflammatory cell infiltration,and collagen volume fraction(CVF)was significantly reduced(P<0.01).The mean optical density(MOD)of α-SMA positive expression was significantly decreased(P<0.01).The levels of serum CK,CK-MB,LDH,NT-proBNP and TGF-β1 were significantly decreased(P<0.01).The expression levels of TGF-β1,Smad2 and Smad3 protein were significantly decreased(P<0.01).The expression levels of COL1A1 and FN mRNA were significantly decreased(P<0.01).Conclusion Gualou Xiebai Banxia Tang significantly reduced the myocardial pathological changes and fibrosis degree of myocardial ischemia model rats,and improved cardiac function.The mechanism may be related to the inhibition of myocardial ECM remodeling by regulating TGF-β1/Smads signaling pathway.