The Effect Of Corilagin On TGF-β1/Smad Signaling Pathway In Chronic Venous Insufficiency

Objective: Chronic venous insufficiency(CVI)is a clinical syndrome caused by venous stasis and reflux,which usually occurs in the lower extremities.Due to the complicated etiology of CVI,the pathogenesis of CVI has not been fully understood,and few drugs can effectively suppress the pathophysiological progression of CVI.Transforming Growth Factor-β 1(TGF-β1),as one of the key factors mediating vascular fibrosis,has attracted much attention in CVI.TGF-β1 exhibits its effects of anti-fibrosis and regulating extracellular matrix remodeling through TGF-β1/Smad pathway,which is one of the central signaling pathways in CVI.Corilagin is a major active ingredient of some herbs such as Phyllanthus.Researches confirmed that it has many pharmacological effects,such as anti-oxidation,anti-inflammation,hepatoprotection,anti-tumor,anti-fibrosis and so on.Our study aims to explore the inhibitory effect of Corilagin on vascular fibrosis through TGF-β1/Smad signaling pathway.And we hope to provide a novel sight for the drug treatment of CVI.Methods: The great saphenous venous specimens of CVI patients were collected as tissue sections.The extent of vascular fibrosis was observed by HE and Masson staining and immunohistochemistry.The m RNA and protein expressions of CTGF,COL1A1,Smad2,p-Smad2 and MMP9 cytokines were determined by real-time q PCR,Western Blot and other experimental techniques.Human Umbilical Vein Endothelial Cell(HUVEC)stimulated by recombinant TGF-β1 was used as cell model.Cellular functional experimental methods like CCK8,wounding healing assay were used for studying the function of Corilagin on the cell model.The m RNA and protein expression of Smad2/3,ERK,JNK,CTGF,collagen I,MMP-9,TIMP-1 and other related cytokines was measured with the treatment of Corilagin after TGF-β1stimulation.Furthermore,the effects of Corilagin were tested when TGF-β1/Smad signaling pathway was inhibited.The above methods were used to determine the effect and mechanism of Corilagin on the targets of TGF-β1/Smad signaling pathway,vascular fibrosis and abnormal distribution of extracellular matrix in cell line.Results: Obvious inflammatory cells infiltration and collagen deposition were observed in the venous sections of CVI patients.The expression of COL1A1 and MMP9 was significantly increased in immunohistochemistry.The transcription and translation levels of TGF-β1/Smad pathway-related molecules and fibrosis markers in the CVI group were significantly higher than those in the control group.In in vitro experiment,the transcription and translation levels of TGF-β1/Smad signaling pathway-related molecules and fibrosis markers in HUVEC were significantly decreased after the treatment with different concentrations of Corilagin,which indicated that Corilagin could significantly inhibit the TGF-β1/Smad signaling pathway.Moreover,this inhibitory effect of Corilagin showed a significant dose-dependentmanner(p < 0.05).In addition,the anti-fibrotic effect of Corilagin was significantly interfered while the TGF-β1 signal pathway inhibitorwas utilized.Conclusion: TGF-β1/Smad signaling pathway can mediate vascular fibrosis,excessive deposition and abnormal distribution of extracellular matrix in the pathogenesis and progression of chronic venous insufficiency.Corilagin can alleviate the process of fibrosis by inhibiting TGF-β1/Smad signaling pathway,which provides a novel sight for drug treatment of chronic venous insufficiency.