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-GB 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 beta-1,6-D-Glcp as its main chain. The results of in vivo experiments show that in comparison with the MG, WABM-A significantly reduced the scrum levels of TC, TG, and LDL-C, increased the serum levels of HDL-C (P< 0.01), and upregulated the liver expression of PPAR gamma, LXR alpha, 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 PPAk gamma, LXR alpha, 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 PPAR-gamma/LXR alpha/ABCA1/ABCG1 cholesterol metabolism pathway. This is the first time that the hypolipidemic effect of Agaricus blazei Morrill acidic polysaccharides has been reported. (C) 2020 Elsevier B.V. All rights reserved.