Protective effect of phosphorylated Athyrium multidentatum (Doll.) Ching polysaccharide on vascular endothelial cells in vitro and in vivo

Abstract

Abstract The purpose of this study was to prepare phosphorylated Athyrium multidentatum (Doll.) Cing polysaccharide (PPS) and investigate its protective effect on vascular endothelial cells (VECs) in vitro and in vivo and the underlying mechanisms. Sodium tripolyphosphate (STPP) and sodium trimetaphosphate (STMP) were used as phosphorylation reagents and PPS was characterized by Fourier transform infrared (FT-IR), 13C nuclear magnetic resonance (13C NMR) and 31P nuclear magnetic resonance (31P NMR) spectra. Chemical analysis demonstrated that PPS was composed of mannose, glucosamine, rhamnose, glucuronic acid, galacturonic acid, galactosamine, glucose, galactose, xylose, arabinose and fucose with a molar ratio of 11.36:0.42:4.03:1.12:1.81:0.26:33.25:24.12:6.85:14.46:2.32 and a molecular weight of 28837 Da. Results from in vitro and in vivo assays revealed that PPS protected human umbilical vein endothelial cells (HUVECs) against H2O2-induced oxidative injury and attenuated VECs damage in mice treated with D-galactose. RNA sequencing (RNA-seq) analysis disclosed that PPS down- or up-regulated the expression of eighteen differentially expressed genes (DEGs) involved in the functions of vascular endothelium repairment, cell growth and proliferation, cell survival and apoptosis, inflammation, angiogenesis and antioxidant in mice abdominal aorta, implying that these biological processes might play crucial roles in the protective actions of PPS on VECs.