[Extracts of Poria cocos polysaccharides improves alcoholic liver disease in mice via CYP2E1 and NF-κB inflammatory pathways].

The present study investigated the effect of extract of Poria cocos polysaccharides(PCP) on cytochrome P450 2 E1(CYP2 E1) and nuclear factor κB(NF-κB) inflammatory signaling pathways in alcoholic liver disease(ALD) mice and explored its protective effect and mechanism. Sixty male C57 BL/6 N mice of SPF grade were randomly divided into a control group, a model group, a positive drug group(bifendate, 200 mg·kg~(-1)), and high-(200 mg·kg~(-1)) and low-dose(50 mg·kg~(-1)) PCP groups. Gao-binge mo-del was induced and the mice in each group were treated correspondingly. Liver morphological and pathological changes were observed and organ index was calculated. Serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were detected. Malondialdehyde(MDA) and superoxide dismutase(SOD) in liver tissues were detected by assay kits. The levels of interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by ELISA. The activation of macrophages was observed by immunofluorescence staining and protein expression of CYP2 E1, Toll-like receptor 4(TLR4), NF-κB p65, and phosphorylated NF-κB p65(p-NF-κB p65) were analyzed by Western blot. The ALD model was properly induced. Compared with the model group, the PCP groups significantly improved the pathological injury of liver tissues. Immunofluorescence staining revealed that compared with the model group, the groups with drug intervention showed decreased macrophages in liver tissues. Additionally, the PCP groups showed reduced ALT, AST, MDA, IL-6, and TNF-α(P<0.05), and potentiated activity of SOD(P<0.01). PCP extract has the protective effect against alcoholic liver injury in mice, and the underlying mechanism may be related to the regulation of the expression of CYP2 E1 and inhibition of TLR4/NF-κB inflammatory signaling pathway to reduce oxidative stress and inflammatory injury, thereby inhibiting the development of ALD.

Poria cocos polysaccharide prevents alcohol-induced hepatic injury and inflammation by repressing oxidative stress and gut leakiness.

Alcoholic liver disease (ALD) is a major worldwide chronic liver disease accompanied by hepatic inflammation, gut leakiness, and abnormal oxidative stress. Our previous study demonstrated substantial hepatoprotective activity of the active Poria cocos polysaccharide (PCP-1C). The present study explored whether PCP-1C protects against ALD among hepatic inflammation, gut leakiness, and abnormal oxidative stress. The results showed that PCP-1C significantly improved alcohol-induced liver injury by decreasing serum biochemical parameters, alleviating hepatic steatosis, and reducing lipid accumulation caused by ALD. Moreover, PCP-1C treatment reduced hepatic inflammation by inhibiting the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway and also improved hepatocyte apoptosis by inhibiting the cytochrome P450 2E1 (CYP2E1)/reactive oxygen species (ROS)/mitogen-activated protein kinases (MAPKs) signaling pathway. Regarding intestinal protection, PCP-1C could repair the intestinal barrier and reduce lipopolysaccharide (LPS) leakage. Generally, PCP-1C exerts a positive therapeutic effect on ALD, which may play a pivotal of decreasing inflammatory factor release, inhibiting oxidative stress and apoptosis, and improving intestinal barrier injury.

Structural characterization and hepatoprotective activity of a galactoglucan from Poria cocos.

To find the polysaccharide with hepatoprotective activity from Poria cocos and clarify its structure, a galactoglucan (PCP-1C) with a molecular weight of 17 kDa was purified from the Poria cocos sclerotium by column chromatography and activity evaluation in the present work. It was composed of galactose, glucose, mannose, and fucose in a molar percentage of 43.5: 24.4: 17.4: 14.6. Structural characterization showed that PCP-1C has a backbone consisted of 1,6-α-D-Galp, which branches composed of 1,3-ß-D-Glcp, 1,4-ß-D-Glcp, 1,6-ß-D-Glcp, T-ß-D-Glcp, T-α-D-Manp, T-α-L-Fucp and 1,3-α-L-Fucp. In vivo experiments found that PCP-1C can apparently improve the damage of liver tissue in CCl4-treated mice and relieve oxidative stress and inflammation. PCP-1C also reduced the expression of CAR and CYP2E1 in the liver. These findings indicated strong hepatoprotective effect of PCP-1C, which was attributed to the reduction of CCl4 metabolism via inhibiting the CAR/CYP2E1 signal pathway.