补中益气汤对高原低氧大鼠肠道屏障的保护作用研究

Protective effect of Buzhong Yiqi Decoction on intestinal barrier in rats with high altitude hypoxia

目的评价补中益气汤对高原低氧暴露大鼠小肠黏膜损伤的调控作用。方法选用7周龄雄性Wistar大鼠18只,适应性饲养7天后采用随机数字表法分成对照组、低氧暴露组、补中益气汤干预组,每组6只。各组动物预先灌胃7天后,除对照组大鼠外,其余采用低压氧舱模拟海拔高度6000米进行高原低氧暴露诱导肠黏膜损伤。记录大鼠体质量和摄食量的变化;苏木精—伊红染色观察空肠组织形态变化,生化法检测大鼠血清髓过氧化物酶(myeloperoxidase,MPO)和二胺氧化酶(diamine oxidase,DAO)活性,酶联免疫吸附法检测胃泌素(gastrin,GAS)水平;二氢乙啶(dihydroethidium,DHE)染色检测空肠组织活性氧(reactive oxygen species,ROS)水平;硫代巴比妥酸法和比色法检测血清超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-PX)和丙二醛(malondialdehyde,MDA)水平;通过免疫蛋白印迹实验检测空肠组织中紧密连接蛋白闭锁蛋白、闭锁小带-1蛋白及闭合蛋白的表达情况。结果与对照组相比,低氧暴露组大鼠体质量和摄食量明显减少(P<0.01),空肠绒毛高度和隐窝深度的比值显著下降(P<0.01);大鼠血清中肠道屏障损伤指标DAO和MPO水平显著增高及GAS分泌降低(P<0.01);大鼠血清中脂质过氧化水平(MDA)升高,抗氧化能力(SOD、GSH-PX)显著降低(P<0.01);空肠组织紧密连接蛋白闭锁蛋白、闭锁小带-1蛋白及闭合蛋白表达水平降低(P<0.05)。与低氧暴露组相比,补中益气汤组绒毛长度和隐窝深度有所恢复(P<0.01);大鼠血清中的DAO和MPO含量显著降低,GAS分泌增加(P<0.01);大鼠血清中的SOD、GSH-PX含量明显升高,MDA水平降低(P<0.01);大鼠空肠组织紧密连接蛋白表达水平显著升高,差异均有统计学意义(P<0.01)。结论补中益气汤可显著改善高原低氧暴露导致的肠黏膜损伤,其可能与改善机体氧化应激损伤,提高肠黏膜紧密连接蛋白的表达有关。

Objective To observe the effect of Buzhong Yiqi Decoction on alleviating intestinal mucosal injury in rats exposed to hypoxia at high altitude.Methods Eighteen 7-weeks-old male Wistar rats were randomly divided into the control group,the hypoxia-exposed group and the Buzhong Yiqi Decoction intervention group,with 6 rats in each group.After gavage for 7 days,all the animals in each group were exposed plateau hypoxia at high altitude to induce intestinal mucosal injury in a low pressure oxygen chamber at an altitude of 6,000 meters,except the rats in the control group.The changes of body mass and food intake of rats were recorded.Hematoxylin-eosin(HE)staining was used to observe the morphological changes of jejunum,the levels of myeloperoxidase(MPO)and diamine oxidase(DAO)in serum of rats were detected by biochemical method,and the level of gastrin(GAS)was detected by enzyme-linked immunosorbent assay.The level of reactive oxygen species(ROS)in jejunum was detected by Dihydroethidium(DHE)staining.The levels of serum superoxide dismutase(SOD),glutathione peroxidase(GSH-PX)and malondialdehyde(MDA)were detected by TBA and colorimetry.Western blot(WB)was used to detect the protein expressions of tight junction proteins Claudin-1,zona atresia-1(ZO-1)and Occludin in jejunum.Results Compared with the control group,the weight and food intake of rats in the hypoxia-exposed group were decreased significantly(P<0.05),and the ratio of jejunum villi height and the depth of crypt were decreased significantly(P<0.05).The levels of DAO and MPO,the indexes of intestinal barrier injury,in serum of rats were significantly increased and the secretion of GAS was decreased(P<0.05).The level of lipid peroxidation(MDA)in serum of rats were increased,and the antioxidant capacity(SOD,GSH-PX)were decreased significantly(P<0.05).The expression levels of Claudin-1,Occludin and ZO-1 in jejunum were decreased(P<0.05).Compared with the hypoxia-exposed group,the villi length and crypt depth of the Buzhong Yiqi Decoction intervention group were recovered(P<0.05).The contents of DAO and MPO in serum of rats were decreased significantly,while the secretion of GAS was increased(P<0.05).The contents of SOD and GSH-PX in serum of rats were significantly increased,while the level of MDA was decreased(P<0.05).The expression level of tight junction protein in rat jejunum increased significantly,and the differences were statistically significant(P<0.05).Conclusion Buzhong Yiqi Decoction can significantly improve intestinal mucosal injury caused by low pressure and Hypoxia exposure at high altitude,which may be related to improving oxidative stress injury and increasing the expression of tight junction protein in intestinal mucosa.