Mechanism of Tongxinluo Capsules in Treating Radiation-Induced Heart Disease by Regulating the TGF-β1/Smad Signaling Pathway
LU Yujie
JIA Yongsen
YANG Huan
SUN Xinyu
LIU Zhilong
CHU Zhanhong
XIAO Li
BAI Guanglei
WU Chao
SUN Yunchuan
Abstract：Objective To explore the ameliorative effect of Tongxinluo Capsules on myocardial fibrosis in rats with radiation-induced heart disease(RIHD)via the transforming growth factor-β1(TGF-β1)/Smad signaling pathway.Method Forty-eight 8-week-old male SPF-grade SD rats were randomly divided into the following groups:blank control group,model group,low-dose Tongxinluo group(0.14 g/kg),medium-dose Tongxinluo group(0.28 g/kg),high-dose Tongxinluo group(0.56 g/kg),and atorvastatin calcium group(0.90 mg/kg),8 per group.Except for the blank control group,the remaining five groups received radiotherapy.Starting from the day after irradiation,the blank control group and model group were administered 0.9%sodium chloride solution by gavage,while the other drug groups received their respective medications by gavage,once daily for 12 weeks.Cardiac ultrasound was used to measure left ventricular ejection fraction(LVEF)and left ventricular shortening fraction(LVFS).Serum levels of cardiac troponin I(cTnI)and creatine kinase-MB(CK-MB)were detected by enzyme-linked immunosorbent assay.Histopathological changes in myocardial tissue were observed using hematoxylin-eosin staining and Masson's trichrome staining.Western blotting was employed to detect the protein expression of TGF-β1,Smad3,p-Smad3,Smad2,p-Smad2,and Smad7 in cardiac tissue.Results Compared with the blank control group,the model group showed decreased LVEF and LVFS at weeks 6 and 12 after administration(P<0.05);increased serum cTnI and CK-MB levels(P<0.05);HE staining revealed significant myocardial cell edema with extensive inflammatory infiltration and elevated pathological scores(P<0.05);Masson staining showed marked myocardial fibrosis and increased collagen volume fraction(CVF)(P<0.05);cardiac tissue exhibited increased expression of TGF-β1,p-Smad3,and p-Smad2 proteins(P<0.05),while Smad7 protein expression was decreased(P<0.05).Compared with the model group,the low-,medium-,and high-dose Tongxinluo groups and the atorvastatin calcium group showed increased LVEF and LVFS at weeks 6 and 12(P<0.05);decreased serum cTnI and CK-MB levels(P<0.05);myocardial cell morphology returned to normal with regular arrangement,inflammatory infiltration was significantly reduced,fibrosis was alleviated,and pathological scores and CVF were decreased(P<0.05);cardiac tissue showed decreased expression of TGF-β1,p-Smad3,and p-Smad2 proteins(P<0.05),while Smad7 protein expression was increased(P<0.05).Conclusion Tongxinluo Capsules ameliorate cardiac injury and reduce myocardial fibrosis in RIHD rats by regulating the TGF-β1/Smad signaling pathway.
Keywords：cardiac injuryradiationTongxinluo capsulesfibrosisTGF-β1/Smad signaling pathway
Publication Date：2026-01-20
Online Publishing Date：2026-01-24(First online date of this platform, not the publication date of the document)
Pages：7( 141-147 )