Structural characterization and protective effect against myocardial fibrosis of polysaccharide from Stellariae Radix (Stellaria dichotoma L. var. lanceolata Bge.)

Abstract

Abstract Cardiovascular disease is characterized by thedevelopment of myocardial fibrosis, Stellariae Radix is a traditional Chinese medicine. A novel polysaccharide named SRP-1 from Stellariae Radix was structurally identified and its effect against myocardial fibrosis was explored. SRP-1 was extracted from Stellariae Radix and purified by DEAE-52 cellulose chromatography. According to physicochemical methods and monosaccharide composition analysis, SRP-1 was found to be mainly composed of galactose, glucose, xylose, fructose, mannose, and rhamnose, and its weight average molecular weight (Mw) was 31,309 Da. Tests of activity against myocardial fibrosis indicated marked downregulation of the expression of Col I, Col III, α-SMA, and proteins related to the TGF-β/Smad signaling pathway, which were induced by TGF-β1, in mouse cardiac fibroblasts pretreated with SRP-1. In addition, SRP-1 restrained the abnormal growth of cardiac fibroblasts cells and the expression of Snail 1, Snail 2, Twist 1, and Slug mRNA in vitro. SRP-1 can reduce the expression of TGF-β/Smad signaling pathway related proteins induced by TGF-β1. Taken together,SRP-1 can protect CFs from myocardial fibrosis induced by TGF-β1 by inhibiting TGF-β/Smad signaling. These results indicate that Stellariae Radix polysaccharide may warrant further analysis as a novel therapeutic agent for cardiovascular diseases.