The Study On Regulating Effects And Mechanism Of Laminaria Japonica On Serum Lipid Of Experimental Hyperlipenmia

Objective To investigate the regulating effects and mechanism of Laminaria japonica (L. japonica) on serum lipid of experimental hyperlipenmia in rats.Methods Sixy healthy female Wistar rats were used to establish hyperlipemia models by feeding fat-rich forage, and the L. japonica was applied as raw materials for potential marine drugs. The levels of serum lipid including the triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL) were detected by biochemical assay. The concentrations of lipid perioxide malondialdehyde (MDA) in serum and hepatic tissue were respectively measured by thiobarbituric acid (TBA) assay, nitric oxide (NO) by nitrate reductase assay. The activity of superoxide dismutase (SOD) in serum and hepatic tissue were determined by oxidase assay. The activities of glutathione peroxidase (GSH-Px), lipoprotein lipase (LPL) and hepatic lipase (HL) in serum and hepatic tissue were determined by chemical colormetry. The levels of ox-LDL, HMG-CoA and the activity of HMG-CR and Lectithin cholesterol acyl transferase (LCAT) in serum and hepatic tissue were respectively determined by the typical ELISA assay. The concentration of protein in hepatic tissue was determined by the BCA assay kit. The expressions of SOD and iNOS in hepatic tissue were deteced by immunohistochemical assay.Results After modelling, the levels of serum TG, TC and LDL in model control group were increased significantly than those in normal control group, while the levels of HDL were increased significantly than those in normal control group, it indicated that the model were succeed. After treatment, the levels of serum TG,TC and LDL in all treated groups decreased significantly than those in model control group, while the levels of HDL were increased significantly than those in model control group (P<0.05). The levels of LPL, HL and LCAT in all treated groups were significantly higher than those in the normal control and model control group (P<0.05). The levels of MDA and NO in treated group were markedly lower than model control group (P<0.05), while the activities of SOD and GSH-Px markedly higher than model control group (P<0.05). The levels of ox-LDL in treated group were markedly higher than model control group (P<0.05), while the activities of HMG-CR were markedly lower than model control group (P<0.05).The iNOS down-expressed and the SOD up-expressed while the granular and fatty degenerative hepatocytes reduced significantly than those in the model control group (P<0.05).Conclusion L. japonica might enable the activities of LPL, HL and LCAT, and then advanced the catabolism of TG, LDL and TC, or it might inhibition the activities of HMG-CR then reduced the synthesis levels of TC, and then affect the synthesis of LDL. Otherwise, the kelp has been certified having anti-oxidation, so that it maybe release the symptom of hyperlipidemia. The results of our study indicate that the midille nose was better than another two noses. But the concrete mechanism was needed further research in order to provide original evidence for the study of the marine drugs.