This study aimed to investigate the effect and underlying mechanism of a purified Laminaria japonica polysaccharide (LJP61A) on preventing vascular calcification (VC). In the adenine-induced chronic renal failure (CRF) mice VC model and the β-glycerophosphate (β-GP)-induced vascular smooth muscle cells (VSMC) calcification model, LJP61A was found to significantly inhibit VC phenotypes as determined by biochemical analysis and von Kossa, alizarin red, and immunohistochemical staining. Meanwhile, LJP61A remarkably up-regulated the mRNA levels of VSMC related markers and down-regulated the mRNA levels of sodium-dependent phosphate cotransporter Pit-1. In addition, LJP61A could significantly decrease the protein levels of core-binding factor-1, osteocalcin, bone morphogenetic protein 2, and receptor activator for nuclear factor-κB ligand, and it can increase the protein levels of osteoprotegerin and matrix gla protein. These results indicated that LJP61A ameliorated VC both in vivo and in vitro via preventing osteoblastic differentiation of VSMC, suggesting LJP61A might be a potential therapeutic agent for VC in CRF patients.
Keywords: chronic renal failure; laminaria japonica; osteoblastic differentiation; polysaccharide; vascular calcification.