Abstract: To characterize the polysaccharide structure of Irpex lacteus and screen active polysaccharides with antiproliferation effect on glomerular mesangial cells (GMC),the effects of active polysaccharides on abnormal GMC proliferation and extracellular matrix secretion were studied.Crude polysaccharide (PC) was extracted by alkali extraction and alcohol precipitation method,and PCP1 and PCP2 were obtained by purification by ion exchange chromatography column and separation by sephadex g50 gel column.The physical and chemical properties,methylation and IR analysis of the polysaccharides were determined by phenol sulfuric acid method and BCA method.MTT assay was used to investigate the effect on the proliferation of glomerular mesangial cells (GMC).As a result,the total sugar content of PCP1 and Pc2 was 98.05% and 96.92%,respectively.PCP1 is mainly composed of Man,Glc and Gal,and the Gal content is the highest.While PCP2 only consists of Glc,the homopolysaccharide with antiGMC proliferative activity is PCP1,which can protect the GMC valueadded induced by LPS and reduce the release of LN and FN proteins.

Key words: Irpex lacteus, polysaccharide, active site, glomerular mesangial cell