Experimental Study Of Lethariella Cladonioides And Polysaccharide Effect In Decreasing Blood Lipid And Protecting Liver

Objective:To extract and analysis of the polysaccharide content in Lethariella cladonioides. Study the lipid-lowering and protecting liver effects of Lethariella cladonioides extract and polysaccharide on nonalcoholic fatty liver disease (NAFLD) in rats and discussing its possible mechanisms.Methods:Part I:The polysaccharide was obtained with the water extraction and alcohol precipitation and dialysis method,proteins were removed by protease. Polysaccharide content of the extraction was determined by the Phenol-sulfuric acid method and3,5-Dinitrosalicylic acid method. Part II: Forty male rats were randomly divided into six groups:normal control group,model control group,high dose group,middle dose group,low dose group and dongbaogaitai group. All of the groups were fed with high glucose and fatty diet except the nomal control group,meanwhile the rats were administered intragastrically with HXC(0.9、2.7、4.5g·kg-1·d-1)and dongbaogantai(1.2g·kg-1·d-1). Levels of ALT, AST、TG、TC、LDL-C and HDL-C in serum, and TC、TG、MDA and SOD in hepatic tissue were detected and the pathological changes of liver were observed under light microscope after six weeks. Part Ⅲ: Forty eight male rats were randomly divided into six groups:normal control group, model group, high dose group, middle dose group, low dose group and dongbaogaitai group. All of the groups were fed with high glucose and fatty diet except the nomal control group,meanwhile, the rats were administered intragastrically with LCP (0.1、0.3、0.5g·kg-1·d-1) and dongbaogantai(1.2g`kg-1·d-1) for six weeks. Afterwards, biochemical indicators levels in serum and hepatic tissue were detected, the pathological changes of liver were observed under microscope and evaluated by NAS.Results:Part I:The polysaccharide content in LCP was82.6%,8.811%equivalent to the content of polysaccharide in Lethariella cladonioides. Part II: Compared with model group,HXC could obviously reduce liver weight and liver index, serum levels of TC, TG, LDL-C and TC、TG、MDA in hepatic tissue were significantly decreased,serum ALT and AST decreased and serum HDL-C、 hepatic SOD significantly increased (P<0.05or P<0.01). Steatosis and hydropic degeneration is remarkably relieved. Part III:The middle dose of LCP (0.3g·kg-1·d-1) significantly reduced wet liver weight and liver index(P<0.01); lowered ALT(P<0.05).Serum levels of TC, TG, LDL-C and TC. TG、MDA in hepatic tissue were significantly decreased (P<0.01), alternatively, hepatic SOD(P<0.05) and GSH (P<0.01) were obviously increased. The steatosis degeneration and hepatocyte ballooning of hepatocellular is remarkably relieved.Conclusion:1.Polysaccharide content of the extraction was determined by the Phenol-sulfuric acid method and3,5-Dinitrosalicylic acid method which determination of the polysaccharide in Lethariella cladonioides is fast, stability, sensitive and reproducible.2. Lethariella cladonioides has effectively protective and therapeutic effects on NAFLD in rats fed with high glucose and fatty diet, whose mechanism might be related to lowering blood lipid and liver lipid level improving hepatic anti-oxidative capability and inhibiting of lipid peroxidation.3. Lethariella cladonioides polysaccharide obviously protected liver and reduced lipid and enzyme on hyperlipidemic fatty liver of rats. Blood lipid, liver lipid and enzyme levels were lowered remarkably by LCP(0.3g·kg-1·d-1). Lethariella cladonioides polysaccharide can also effectively protect liver by improving anti-oxidative capability, inhibiting lipid peroxidation and eliminating the oxide free radical of the body.