Effects of Yulangsan Extracts on Enzymes of Lipoprotein Metabolism and Fatty Liver in Hyperlipidemic Rats Induced by High Fat Diet

Objective: To explore the effects of the Yulangsan(YLS) extracts(YLS flavonoids,polysaccharide and aqueous extract) on enzymes of lipoprotein metabolism and fatty liver in the hyperlipidemic rats induced by high fat diet.Method: Eighty healthy SD rats were raised by hyper-fatty feed for 6 weeks to induce the hyperlipidemia rat model.Then the rats were divided into 8 groups randomly according to their serum TC: model group,high dose group of YLS flavonoids(YFH),low dose group of YLS flavonoids(YFL),high dose group of YLS polysaccharide(YPH),low dose group of YLS polysaccharide(YPL),high dose group of YLS aqueous extract(YAH),low dose group of YLS aqueous extract(YAL) and lovastatin group.Model group and blank control group were given with vehicles(15 g·kg-1·d-1),lovastatin group was given with lovastatin solution(3.0 mg·kg-1·d-1),YFH and YFL groups were given with YLS flavonoids(0.1 g·kg-1·d-1 and 0.025 g·kg-1·d-1 respectively),YPH and YPL groups were given with YLS polysaccharide(0.15 g·kg-1·d-1 and 0.037 5 g·kg-1·d-1 respectively),YAH and YAL groups were given with YLS aqueous extract(15.00 g·kg-1·d-1 and 3.75 g·kg-1·d-1 respectively).Serum lipoprotein level,lipoprotein lipase(LPL),hepatic lipase(HL),superoxide dismutase(SOD) and malondialdehyda(MDA) were tested after treated with corresponding drugs once per day for 14 days,and the changes of pathomorphology of liver tissue were observed by HE dye.Result:Compared with the model group,the levels of the serum TC,TG,LDL-C,and MDA were decreased significantly,while HDL-C,LPL,HL and SOD were increased significantly(P0.05 or P0.01).In all treated groups,the liver weight,liver coefficient decreased significantly,and the liver adipose degeneration was ameliorated in some degree after the treatment with YLS extracts.High-and low-dose groups of YLS flavonoids had especially the most obvious improved effects.Conclusion:The lipid metabolic disorder and the liver adipose degeneration in hyperlipidemia rats were improved significantly after the treatment with YLS extracts,which may be related with the increase on enzyme activity of lipoprotein metabolism and SOD.