肠三叶因子对坏死性小肠结肠炎新生鼠肠组织中P-ATK及P-BAD的影响及意义

Effect and Significance of Intestinal Trefoil Factor on p-AKT and p-BAD in Neonatal Rats with Necrotizing Enterocolitis

目的观察肠三叶因子(ITF)对新生鼠坏死性小肠结肠炎(NEC)模型磷酸化丝氨酸-苏氨酸蛋白激酶(p-AKT)及磷酸化BAD(p-BAD)蛋白水平的影响,探讨ITF对NEC的保护作用。方法新生鼠50只,随机分为5组,每组10只。建立NEC模型,A组腹腔注射生理盐水0.2 ml;B组腹腔注射ITF 0.2 mg;C组腹腔内注射渥漫青霉素0.1 mg/kg;D组腹腔内注射ITF 0.2 mg+渥漫青霉素0.1 mg/kg;E组为正常对照组。实验第4天断头处死大鼠,取近回盲部肠道组织做病理学检查,分别采用免疫组化方法及免疫印迹法检测肠组织中p-AKT及p-BAD蛋白表达水平。结果 5组肠组织中p-AKT及p-BAD蛋白表达水平比较,差异有统计学意义(P均<0.05),B组p-AKT、p-BAD蛋白表达水平高于其他4组(P均<0.05),A组高于E组(P均<0.05),C组p-AKT最低(P<0.05)。各组大鼠肠损伤病理评分比较,差异有统计学意义(P<0.05),A、C、D组肠损伤病理评分高于B组(P<0.05)。结论 ITF可减轻新生鼠NEC的肠道炎症反应,其机制可能是使AKT活化为p-AKT,其作用于下游靶点p-BAD,抑制BAD的促凋亡作用。

Objective To observe the effects of intestinal trefoil factor（ITF） on the levels of p-AKT and p-BAD in the necrotizing enterocolitis（ NEC） model of neonatal rat,and to investigate the protective effect of ITF on NEC.Methods Fifty neonatal rats were randomly divided into 5 groups,with 10 rats in each group. The NEC model of neonatal rats was established. Group A was given intraperitoneal injection of normal saline（0. 2 ml）,group B was given intraperitoneal injection of ITF（0. 2 mg）,group C was given intraperitoneal injection of wortmannin（0. 1 mg /kg）,group D was given intraperitoneal injection of ITF（0. 2 mg） and wortmannin（0. 1 mg /kg）,and group E as normal control group. All the subjects were put to death on the 4th day after experiment. The intestinal tissues located at the boundary of ileum and cecum were obtained to observe histological changes. Immunohistochemical method and Western Blot were used to detect the levels of p-AKT and p-BAD in intestinal tissues. Results There were significant differences in the levels of p-AKT and p-BAD in intestinal tissues among 5 groups（P〈0. 05）. The levels of p-AKT and p-BAD in group B were higher than those in other four groups（all P〈0. 05）. The levels of p-AKT and p-BAD in group A were higher than those in group E（all P〈0. 05）. The level of p-AKT was the weakest in group C（P〈0. 05）. There was significant difference in the pathology score of intestinal injury among groups（P〈0. 05）. The pathology score of intestinal injury in group A,group C and group D was higher than that in group B（P〈0. 05）. Conclusion ITF might relieve the intestinal inflammation of neonatal rats with NEC by AKT activation to p-AKT. It might play a role in p-BAD,and suppress the apoptosis-promoting effect of BAD.