Li Bo, Zani Augusto, Lee Carol, Zani-Ruttenstock Elke, Zhang Ziyi, Li Xinpei, Ip Wan, Gonska Tanja, Pierro Agostino
Division of General and Thoracic Surgery, Physiology and Experimental Medicine Program, The Hospital for Sick Children, Toronto, ON, Canada.
Department of Pediatrics and Gastroenterology, The Hospital for Sick Children, Toronto, ON, Canada.
J Pediatr Surg. 2016 Jun;51(6):1001-4. doi: 10.1016/j.jpedsurg.2016.02.073. Epub 2016 Mar 2.
Maternal separation (MS) leads to intestinal barrier dysfunction in neonatal mice. Endoplasmic reticulum (ER) stress is associated with apoptosis and pro-inflammatory response induction. We hypothesized that MS induced gut damage is associated with ER stress and that administration of an ER stress inhibitor protects gut damage.
C57BL/6 mice received intraperitoneal PBS (n=10) or Salubrinal (1mg/kg/day, n=10). MS was performed soon after treatment for 3h daily between P5 and P9. Ten untreated neonatal mice served as control. The colon was harvested on P9 and analyzed for ER stress markers (BiP, CHOP), apoptosis (CC3), goblet cell number per crypt and crypt length (Alcian blue, hematoxylin/eosin), and transcellular permeability (Ussing chamber). Groups were compared using one-way ANOVA with Bonferroni post-test.
Compared to controls, MS mice had higher relative protein expression of ER stress and apoptosis markers (p<0.05) and reduced goblet cell number per crypt and crypt length (p<0.001). In comparison to PBS mice, Salubrinal treated mice had higher goblet cell number (p<0.05), crypt length (p<0.001), and lower transcellular permeability (p<0.05).
Maternal separation induces ER stress and causes colon damage, but ER stress inhibitor protects morphology and permeability. This provides insights on bowel pathogenesis and potential novel treatments for diseases such as necrotizing enterocolitis.
母体分离（MS）会导致新生小鼠肠道屏障功能障碍。内质网（ER）应激与细胞凋亡和促炎反应诱导有关。我们推测，MS诱导的肠道损伤与ER应激有关，并且给予ER应激抑制剂可保护肠道损伤。
C57BL/6小鼠腹腔注射磷酸盐缓冲液（PBS，n = 10）或Salubrinal（1mg/kg/天，n = 10）。在出生后第5天至第9天，每天治疗后不久进行3小时的MS操作。10只未治疗的新生小鼠作为对照。在出生后第9天收获结肠，分析ER应激标志物（结合免疫球蛋白重链结合蛋白、C/EBP同源蛋白）、细胞凋亡（半胱天冬酶3）、每个隐窝的杯状细胞数量和隐窝长度（阿尔新蓝、苏木精/伊红染色）以及跨细胞通透性（尤斯灌流小室）。使用单因素方差分析和Bonferroni事后检验对各组进行比较。
与对照组相比，MS小鼠的ER应激和细胞凋亡标志物相对蛋白表达更高（p<0.05），每个隐窝的杯状细胞数量和隐窝长度减少（p<0.001）。与PBS处理的小鼠相比，Salubrinal处理的小鼠杯状细胞数量更多（p<0.05），隐窝长度更长（p<0.001），跨细胞通透性更低（p<0.05）。
母体分离诱导ER应激并导致结肠损伤，但ER应激抑制剂可保护形态和通透性。这为肠道发病机制以及坏死性小肠结肠炎等疾病的潜在新治疗方法提供了见解。
