有氧运动补充枸杞多糖通过调节Foxp3/RORγT平衡影响非酒精性脂肪肝大鼠的肠道免疫屏障功能

Aerobic exercise supplementation of Lyciumbarbarum polysaccharide affects intestinal immune barrier function in rats with nonalcoholic fatty liver by regulating RORγt/Foxp3 balance

目的探讨有氧运动补充枸杞多糖对NAFLD大鼠肠黏膜免疫屏障的保护作用。方法选取健康8周龄SD大鼠46只,自适应喂养1周后,将大鼠随机分为2组,分别为对照组(n=11)和高脂组(n=35)。第12周末2组各随机选取3只大鼠,判断造模情况。第13周开始干预,高脂组随机分为4组(每组8只),高脂模型组(HFD组)喂养高脂肪饲料,枸杞多糖组(LBP组)喂养高脂肪饮食和枸杞多糖,有氧运动组(AE组)喂养高脂肪饮食并进行中强度有氧运动,枸杞多糖联合有氧运动组(LBP+AE组)喂养高脂肪饮食和枸杞多糖并进行中强度有氧运动,共干预9周。收集其结肠组织及血清,采用蛋白印迹法测定大鼠结肠组织中RORγT、Foxp3、STAT3、STAT5蛋白的表达情况;采用酶联免疫法(ELISA)检测大鼠血清中IL-17及SIgA的含量;采用AB-PAS染色,观察大鼠结肠组织切片中杯状细胞的变化。结果与对照组相比,HFD组的Foxp3蛋白的表达水平及Foxp3/RORγT显著降低(P<0.05);RORγT蛋白表达水平显著增高(P<0.05)。与HFD组相比,有氧运动补充枸杞多糖能够显著增加Foxp3蛋白表达水平及Foxp3/RORγT相对比值,降低RORγT蛋白表达水平。与对照组相比,HFD组的STAT3蛋白表达水平显著增高,LBP组、AE组以及LBP+AE组的STAT3蛋白表达较HFD组显著降低(P<0.05);HFD组的STAT5蛋白表达水平显著降低,且明显低于LBP组、AE组和LBP+AE组(P<0.05)。与对照组相比,HFD组中血清分泌性免疫球蛋白A(SIgA)含量减少,而LBP组、AE组及LBP+AE组血清中SIgA显著高于HFD组(P<0.05);AB-PAS染色结果显示,与对照组相比HFD组结肠杯状细胞数量明显减少,而LBP组、AE组及LBP+AE组中杯状细胞数量显著增加(P<0.05)。结论有氧运动补充枸杞多糖能够通过调节Foxp3/RORγT平衡,对NAFLD大鼠肠道免疫屏障功能发挥一定的保护作用。

Objective To investigate the protective effect of aerobic exercise supplementation of Lycium barbarum polysaccharide on intestinal mucosal immune barrier in rats with NAFLD.Methods Forty-six healthy 8-week-old SD rats were selected and randomly divided into two groups:control group(n=11)and high fat group(n=35)after adaptive feeding for one week.At the end of the 12th week,3 rats in each group were randomly selected to judge the modeling situation.At the 13th week,the high fat group was randomly divided into 4 groups(n=8).The high fat model group(HFD)was fed high fat diet,and the lycium barbarum polysaccharide(LBP group)was fed high fat diet and lycium barbarum polysaccharide.The aerobic exercise group(AE group)was fed high fat diet and performed moderate intensity aerobic exercise,while the lycium barbarum polysaccharide combined with aerobic exercise group(LBP+AE group)was fed high fat diet and lycium barbarum polysaccharide and performed moderate intensity aerobic exercise,with a total intervention of 9w.The expressions of RORγt,Foxp3,STAT3 and STAT5 in the colonic tissues of rats were detected by western blotting.The contents of IL-17 and slgA in serum of rats were determined by enzyme-linked immunoassay(ELISA).The changes of goblet cells in colonic slices of rats were observed by AB-PAS staining.Results Compared with the control group,Foxp3 protein expression level and Foxp3/RORγt in HFD group were significantly decreased(P<0.05);the expression level of RORγT protein was significantly increased(P<0.05).Compared with HFD group,aerobic exercise supplementation of Lycium barbarum polysaccharide significantly increased Foxp3 protein expression level and Foxp3/RORγt relative ratio(P<0.05),decreased the expression level of RORγT protein(P<0.05).Compared with the control group,STAT3 protein expression level in HFD group was significantly increased(P<0.05),the expression level of STAT5 protein was significantly decreased(P<0.05);compared with HFD group,and significantly higher than LBP group,AE group and LBP+AE group(P<0.05).Compared with the control group,STAT5 protein expression was significantly decreased in HFD group(P<0.05),and significantly lower than that in LBP group,AE group and LBP+AE group(P<0.05).Compared with the control group,serum secretory immunoglobulin A(sIgA)content was decreased in HFD group(P<0.05),and serum sIgA in LBP,AE and LBP+AE groups was significantly higher than that in HFD group(P<0.05);AB-PAS staining showed that the number of goblet cells in colon decreased significantly in HFD group compared with control group,while the number of goblet cells in LBP,AE and LBP+AE intervention groups increased significantly(P<0.05).Conclusion Lycium barbarum polysaccharide supplementation with aerobic exercise can regulate Foxp3/RORγt balance,and it plays a protective role in intestinal immune barrier function of NAFLD rats.