全胃肠外营养对幼鼠肠道炎症损伤作用研究

Study on the effect of total parenteral nutrition on intestinal inflammatory injury in young rats

摘要:

目的 探讨全胃肠外营养对幼鼠肠道炎症损伤的作用及机制。方法 选取18只6～8周龄雄性SD幼鼠，随机分为正常组、对照组和观察组，每组6只。观察组幼鼠行右颈静脉置管后给予全胃肠外营养治疗，并禁食、水；对照组幼鼠行右颈静脉置管后给予生理盐水治疗；正常组不予以置管。正常组和对照组幼鼠均喂食标准鼠粮和水，14 d后处死幼鼠，获取肠道组织。采用HE染色观察各组幼鼠肠道组织的病理变化，TUNEL染色观察各组幼鼠小肠上皮细胞凋亡情况，实时荧光定量聚合酶链反应（qRT-PCR）和Western blotting检测各组幼鼠肠道组织中的肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）和白细胞介素-10（IL-10）、Occludin和ZO-1的mRNA和蛋白表达，免疫组织化学检测各组幼鼠肠道组织中的Occludin、ZO-1的表达。结果 观察组幼鼠的肠道组织均出现不同程度的损伤；与正常组和对照组比较，观察组肠上皮细胞凋亡率升高（P <0.05），TNF-α、IL-1β的mRNA和蛋白表达升高（P <0.05），而IL-10、Occludin、ZO-1的mRNA和蛋白表达降低（P <0.05）；免疫组织化学结果显示，Occludin、ZO-1表达下降（P <0.05）。结论 持续2周的全胃肠外营养可导致幼鼠肠道功能受损，促炎因子增加，肠道机械屏障功能受损，尽可能恢复肠内营养对于减少肠道并发症具有重要意义。

Abstract:

Objectives To investigate the effect and mechanism of intestinal inflammatory damage caused by total parenteral nutrition (TPN).Methods Eighteen male 6- to 8-week-old Sprague-Dawley young rats were randomly divided into three groups of six each: the control group, and the TPN group. The right jugular vein was catheterized to provide TPN to rats in the TPN group, who were also placed in abrosia and given water. Rats in the control group were catheterized through the right jugular vein and continuously infused with normal saline, while rats in the normal group were not catheterized. Rats in normal group and control group were fed standard rat food and water, and rats were sacrificed after 14 days to obtain intestinal tissue. The pathological changes in the intestinal tissues of rats were observed using HE staining, the apoptosis of small intestinal epithelial cells was observed using TUNEL staining, the mRNA and protein expression of TNF-α, IL-1β, IL-10, Occludin, ZO-1 were detected in the intestinal tissues of each group using qRT-PCR and Western blotting, and the expression of Occludin and ZO-1 in the intestinal tissues of rats in each group, and both Occludin and ZO-1 expression in the intestinal tissues of each group of young rats was detected by immunohistochemistry.Results Rats in the TPN group suffered varied degrees of damage to their intestinal tissues. When compared to the normal group and the control group, the TPN group's intestinal epithelial cells had a significantly higher rate of apoptosis (P < 0.05), higher levels of TNF-α and IL-1β mRNA and protein expression (P < 0.05), and lower levels of IL-10, Occludin, and ZO-1 mRNA and protein expression (P < 0.05). The expression of Occludin and ZO-1 dramatically decreased, according to the immunohistochemistry findings (P < 0.05).Conclusion TPN for more than two weeks can cause rats to have compromised intestinal function, elevated pro-inflammatory factors, and compromised intestinal mechanical barrier function; therefore, it is crucial to restore enteral nutrition as much as possible to minimize intestinal problems.