Huoxin Pill(活心丸)Attenuates Cardiac Fibrosis by Suppressing TGF-β1/Smad2/3 Pathway in Isoproterenol-Induced Heart Failure Rats

Objective:To evaluate the effects of Huoxin Pill(活心丸,HXP)on cardiac fibrosis and heart failure(HF)in isoproterenol(ISO)-induced HF rats.Methods:Thirty Wistar rats were randomly divided into 5 groups including control,HF,isosorbide mononitrate(ISMN),HXP low(HXP-L),and HXP high(HXP-H)groups(n=6 for each group)according to the complete randomization method.Rats were pretreated with ISMN(5 mg/kg daily),low concentration of HXP(10 mg/kg daily)or high concentration of HXP(30 mg/kg daily)or equal volume of saline by intragastric administration for 1 week,followed by intraperitoneal injection of ISO(10 mg/kg,14 days),and continually intragastric administrated with above medicines or saline for additional 6 weeks.The effects of HXP treatment on the cardiac function,heart weight index(HWI),pathological changes,and collagen content were further assessed.Moreover,the role of HXP on activation of transforming growth factor-β1(TGF-β1)/Smads pathway was further explored using immunohistochemistry(IHC)and Westernblot assay.Results:HXP treatment significantly alleviated the decrease of ejection fraction(EF)and fractional shortening(FS),while decreased the elevation of left ventricular end-systolic volume(LVESV)in ISO-induced HF rats(P<0.05).Moreover,HXP treatment obviously attenuated the increase of HWI and serum level of creatine kinase MB(CK-MB,P<0.05),as well as pathological changes in ISO-induced HF rats.Further determination indicated that HXP treatment alleviated the elevation of collagenⅠand collagenⅢprotein expression in cardiac tissues of ISO-induced HF rats.Furthermore,HXP treatment significantly down-regulated the increase of TGF-β1 and p-Smad2/3 protein expression in cardiac tissues of HF rats(P<0.05),while did not affect the expression of total Smad2/3.Conclusions:HXP attenuated heart failure and cardiac fibrosis in ISO-induced HF rats by suppression of TGF-β1/Smad2/3 pathway.