Activation of autophagy in rats with plateau stress-induced intestinal failure

Hypobaric hypoxia may damage the intestinal mucosa, which may induce multiple organ dysfunction. However, little work has been done regarding whether high altitude hypoxia is associated with failure of the intestinal mucosal barrier. The aim of this study was to investigate the change of the autophagy after the intestinal failure in rats acutely exposed to plateau stress. Fifty Wistar rats were randomly divided into five groups: the plain group, plateau for 6 h, 12 h, 24 h, and 48 h (n = 10 in each group). The acute exposure to plateau was established at a simulated altitude of 4767 meters (m) in a decompression chamber. Intestinal injury was verified by light microscopy. The autophagosomes in the intestinal epithelial cells were observed by transmission electron microscopy (TEM). The protein expression of Beclin1 and LC3B in the intestinal epithelial cells were analyzed by immunohistochemistry. Compared with the plain group, acute exposure to plateau led to a time-dependent damage of the intestinal epithelium. The autophagosome was observed after the intestinal failure following acute exposure to high altitude for 6 h. The expression of Beclin1 and LC3B protein in the rats exposed to acute plateau for 6 h, 12 h, 24 h and 48 h were significantly higher than those in the plain group. The expression of autophagy also showed a significant increase in rats with intestinal failure following acute exposure to plateau stress.