葛仙米对高脂血症小鼠氧化应激的保护作用

Protective Effect of Nostoc sphaeroids Kütz on Oxidative Stress in Hyperlipidemic Mice

大多数与衰老相关的健康问题,如皱纹、心脏病和阿尔茨海默氏症,都是由体内过度的氧化应激引起的。高脂饮食(HFD)引起的高脂血症会导致机体脂质代谢紊乱、氧化应激等,为探究葛仙米对饮食诱导的小鼠高脂血症的保护作用,实验选用6周龄C57BL/6J雄性小鼠,先喂饲高脂饲料(HFD)4周,然后在高脂饲料中添加不同剂量的葛仙米饲喂6周。结果表明,高脂饮食可导致小鼠高脂血症和明显的血脂异常。高脂饮食中添加葛仙米可降低血清甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C),升高高密度脂蛋白胆固醇(HDL-C),能显著降低肝指数和丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)活性。2.5%和7.5%葛仙米组小鼠肝组织丙二醛(MDA)含量显著降低,总抗氧化能力(T-AOC)、肝组织超氧化物歧化酶(SOD)和谷胱甘肽(GSH)含量显著升高(P<0.05)。此外,葛仙米还能显著增加肝组织低密度脂蛋白受体、CYP7a1和LXR-α的表达(P<0.05)。综上,葛仙米对高脂饲料喂养的小鼠具有降脂作用,其机制可能与提高LDLR和CYP7a1的抗氧化活性及基因表达有关。

Most health problems associated with aging,such as wrinkles,heart disease and Alzheimer’s disease were caused by excessive oxidative stress in the body.Hyperlipidemia caused by high-fat diet(HFD)would lead to lipid metabolism disorder,oxidative stress and so on.The purpose of this study was to investigate the protective effect of Nostoc sphaeroids Kütz(NSK)on diet-induced hyperlipidemia in mice.In the experiment,six-week-old C57 BL/6 j male mice were fed with high-fat diet(HFD)for 4 weeks,and then fed with high-fat diet supplemented with different doses of NSK for 6 weeks.Results showed that:High-fat diet could lead to hyperlipidemia and obvious dyslipidemia in mice.The addition of NSK to high-fat diet decreased serum triglyceride(TG),serum total cholesterol(TC),low density lipid cholesterol(LDL-C),while high density lipid cholesterol(HDL-C)increased significantly(P<0.05).It could also significantly reduce the liver index and the enzyme activities of alanine transaminase(ALT)and aspartate transaminase(AST).Through the results of this experiment,it was found that the level of malondialdehyde(MDA)in the liver tissue of 2.5%and 7.5%NSK group decreased,while total antioxidant capacity(T-AOC),hepatic superoxide dismutase(SOD)and glutathione(GSH)increased,and the difference was statistically significant(P<0.05).Furthermore,the expression of LDLR,CYP7 a1 and LXR-αin liver tissue of mice supplemented with NSK in HFD significantly increased(P<0.05).In conclusion,NSK hadlipid-lowering effect on HFD-fed mice and it might be related to increase the antioxidant activity and gene expression of LDLR and CYP7 a1.