Effect of cardiac contractility modulation on TGFβ1/Smad/CTGF signaling pathway / 中华老年心脑血管病杂志

ABSTRACT

Objective To study the effect of cardiac contractility modulation (CCM) on TGFβ1/Smad/CTGF signaling pathway.Methods A rabbit heart failure (HF) model was established by ligating the ascending aortic root.Thirty rabbits were divided into sham operation group (n=10),HF group (n=10) and CCM group (n=10).Myocardial tissue collagen Ⅰ and collagen Ⅲ were analyzed with Sirius red staining,myocardial tissue hydroxyproline level was measured by chromometry,and expressions of TGFβ1,Smad3,Smad7,CTGF were detected by Western blot in 3 groups.Results Collagen Ⅰ,collagen Ⅲ and hydroxyproline content were highcr in HF group than in sham operation group,while collagen Ⅰ,collagen Ⅲ and hydroxyproline conten were lower in CCM group than in sham operation group (0.69±0.05 μg/mg vs 0.98±0.04 μg/mg,P＜0.05).The expression levels of TGFβ1,Smad3,CTGF were higher while those of Smad7 were lower in HF group than in sham operation group (P＜0.05).The expression levels of TGFβ1,Smad3,CTGF were lower while those of Smad7 were higher in CCM group than in HF group (0.49±0.03 vs 0.67±0.04,0.43±0.06 vs 0.59±0.06,0.45±0.08 vs 0.75±0.09,P＜0.05;0.43±0.08vs 0.26±0.04,P＜0.05).Conclusion CCM can improve the myocardial fibrosis in HF rabbits by downregulating the expression of TGFβ1,Smad3,CTGF and upregulating the expression of Smad7.