ABSTRACT
Objective To study the mechanism of cucurbitacin B (CuB) underlying pressure over load-induced myocardial fibrosis.Methods Sixty C57 mice were divided into sham operation group,CuB treatment group,aorta ligation group,CuB+aorta ligation group (15 in each group).The animals received intragastric gavage (0.2 mg/kg · 2 d) one week after operation and a myocardial fibrosis model of mice was induced by aorta ligation 4 weeks after operation.Microvascular density (MVD) was detected with immunohistochemical staining.Expressions of α-SMA,CD31,CD34,vimentin and endothelial-mesenchymal transition (EndMT) were detected by Western blot with immunofluorescence staining.Results No significant difference was found in cardiac MVD,and expression level of α-SMA,vimentin,CD31 and CD34 between sham operation group and CuB group 4 weeks after operation (P＞0.05).The cardiac MVD and expression level of CD31 and CD34 were significantly lower while the expression level of α-SMA and vimentin was significantly higher in aorta ligation group than in sham operation group 4 weeks after operation (P＜0.05).The cardiac MVD and expression level of CD31 and CD34 were significantly higher while the expression level of α-SMA and vimentin was significantly lower in CuB+aorta ligation group than in aorta ligation group 4 weeks after operation (P＜0.05).Conclusion CuB can attenuate cardiac fibrosis by regulating EndMT.