Isolation and purification of acidic polysaccharides from Agaricus blazei Murill and evaluation of their lipid-lowering mechanism.

Polysaccharides are important active constituents of Agaricus blazei Morrill. In the present study, WABM-A was isolated from WABM using DEAE-cellulose, and subsequently purified using sepharose CL-6B to obtain the acidic polysaccharide WABM-A-b. WABM-A-b is mainly composed of Glc dextran, with a molecular weight of 10 KDa and β-1,6-D-Glc p as its main chain. The results of in vivo experiments show that in comparison with the MG, WABM-A significantly reduced the serum levels of TC, TG, and LDL-C, increased the serum levels of HDL-C (P < 0.01), and upregulated the liver expression of PPARγ, LXRα, ABCA1, and ABCG1 in rats with hyperlipidemia (P < 0.05). The results of in vitro experiments show that in comparison with the MG group, WABM-A-b-H significantly reduced the levels of TC and TG in HepG2 cells induced by oleic acid (P < 0.01), and significantly upregulated the protein expression of PPARγ, LXRα, ABCA1, and ABCG1 (P < 0.05). The present study demonstrates that WABM-A-b is an acidic glucan with lipid-lowering activity. The lipid-lowering mechanism of WABM-A-b is via the activation of the PPARγ/LXRα/ABCA1/ABCG1 cholesterol metabolism pathway. This is the first time that the hypolipidemic effect of Agaricus blazei Morrill acidic polysaccharides has been reported. • Agaricus Blazei Murill acidic polysaccharide (WABM-A) is purified from Agaricus blazei Murrill. • WABM-A has a lipid-lowering effect in vivo. • WABM-A-b is isolated and purified from WABM-A. • WABM-A-b is mainly composed of Glc dextran, with a molecular weight of 10 KDa and β-1,6-D-Glc p as its main chain. • WABM-A-b, as a lipid-lowering β-glucan, activates the PPARγ/LXRα/ABCA1/ABCG1 cholesterol metabolism pathway in vitro. [ABSTRACT FROM AUTHOR]