A heteropolysaccharide, l-fuco-d-manno-1,6-α-d-galactan extracted from Grifola frondosa and antiangiogenic activity of its sulfated derivative

The tumor growth and metastasis are angiogenesis dependent, thus blockade of angiogenesis is a promising approach for treatment of cancer. Herein we reported the structural and biological features of a novel water-soluble polysaccharide named GFPW from the fruit body of Grifola frondosa. Chemical and spectral analysis revealed that GFPW with an average molecular weight of 15.7 kDa, possessed a backbone consisting of α-1,6-linked galactopyranosyl residues, with branches attached to O-2 of α-1,3-linked fucose residues and α-terminal mannose. By the chlorosulfonic acid–pyridine method, we prepared a sulfated derivative of GFPW, Sul-GFPW, with a substitution degree of 0.33. According to the 13C NMR spectrum, the substitution position was deduced at C-2 and C-3. The angiogenesis assays in vitro showed that Sul-GFPW significantly inhibited endothelial cell proliferation in a dose- and time-dependent manner, and reduced endothelial cell migration and tube formation as well.