目的:探讨银耳多糖(Tremella fuciformis polysaccharides,TFP)对小鼠力竭运动性氧化损伤的影响,并分析其机制.方法:采用TFP处理L6细胞 48 h,CCK-8法检测L6的活力;L6细胞设置 3组,包括对照组、H2O2 组、H2O2+TFP组,孵育 48 h,生化分析仪检测乳酸(Lactic Acid,LA)水平,Western blot实验检测Nrf2、NQO1和HO-1 蛋白水平;将C57BL/6小鼠随机分为 4组(每组n=10),包括模型组、模型+TFP组(50、100、200 mg/kg),模型+TFP组连续灌胃TFP,模型组灌胃相同剂量的蒸馏水,每天1次,连续2周.末次给药30 min后进行力竭运动,记录力竭游泳运动时间,采用酶联免疫吸附试验(ELISA)检测肝糖原(LG)、骨骼肌糖原(MG);ELISA法检测血尿素氮(BUN)、LA、ROS、丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)、TNF-α、IL-6、NF-κBp65水平.Western blot实验检测Nrf2、NQO1、HO-1蛋白水平.结果:H2O2 组L6细胞的LA水平极显著(P<0.01)高于对照组,Nrf2、NQO1、HO-1蛋白水平极显著(P<0.01)低于对照组,TFP极显著(P<0.01)降低培养基中LA水平,极显著(P<0.01)上调L6细胞中Nrf2、NQO1、HO-1表达.TFP显著延长力竭游泳时间(P<0.05,P<0.01),极显著降低 LA(P<0.01)、BUN(P<0.05,P<0.01)水平,显著增加肝糖原(P<0.05,P<0.01)和肌糖原(P<0.05,P<0.01)水平,极显著上调 SOD(P<0.01)、GSH-Px(P<0.01),显著下调MDA(P<0.05,P<0.01)、ROS(P<0.01)水平,极显著(P<0.01)降低血清中TNF-α、IL-6、NF-κBp65的水平;与模型组比较,TFP显著增加Nrf2(P<0.05,P<0.01)、HO-1(P<0.05,P<0.01)、NQO-1(P<0.05,P<0.01)蛋白表达水平.结论:TFP通过抑制氧化应激、炎症改善力竭游泳运动引起的氧化损伤,其机制与调节Nrf2/HO-1信号通路相关.
Objective:To investigate the effect of Tremella fuciformis polysaccharides(TFP)on oxidative damage induced by exhaustive exercise in mice and analyze its mechanism.Methods:L6 cells were treated with TFP for 48 hours,and the activity of L6 was detected by CCK-8 method.L6 cells were divided into three groups,including the control,H2O2,and H2O2+TFP groups,and incubated for 48 hours.LA levels were measured by a biochemical analyzer,and Nrf2,NQO1,and HO-1 protein levels were detected by Western blot assay.C57BL/6 mice were randomly divided into four groups(n=10 for each group),including model group and model+TFP group(50,100,200 mg/kg).The model+TFP groups were continuously gavaged with TFP,while the model group was gavaged with the same dose of distilled water once a day for two consecutive weeks.Exhaustive exercise was performed 30 minutes after the last administration,the duration of exhaustive swimming exercise was recorded,and enzyme-linked immunosorbent assay(ELISA)was used to detect liver glycogen(LG)and skeletal muscle glycogen(MG).ELISA was used to detect blood urea nitrogen(BUN),lactic acid(LA),ROS,malondialdehyde(MDA),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),TNF-α,IL-6 and NF-κBp65 levels.Western blot assay was used to detect the levels of Nrf2,NQO1,and HO-1 proteins.Results:The LA levels of L6 cells in the H2O2 group were significantly(P<0.01)higher than those in the control group,while the protein levels of Nrf2,NQO1,and HO-1 were significantly(P<0.01)lower than those in the control group.TFP could significantly(P<0.01)reduce the LA levels in the culture medium and upregulate the expression of Nrf2,NQO1,HO-1 in L6 cells.TFP could significantly prolong exhaustive swimming time(P<0.01),reduce LA(P<0.01)and BUN(P<0.05,P<0.01)levels,increase liver and muscle glycogen levels(P<0.05,P<0.01),upregulate SOD(P<0.01)and GSH-Px(P<0.01),downregulate MDA(P<0.05,P<0.01)and ROS(P<0.01)levels,and reduce TNF-α(P<0.01),IL-6(P<0.01)and NF-κBp65(P<0.01).Compared with the model group,TFP could significantly increase Nrf2(P<0.05,P<0.01),HO-1(P<0.05,P<0.01)and NQO-1(P<0.05,P<0.01)protein expression levels.Conclusion:TFP improved oxidative damage caused by exhaustive swimming by inhibiting oxidative stress and inflammation,and its mechanism was related to regulating the Nrf2/HO-1 signaling pathway.