【Animal modeling】-The effect of glutamine combined with umbilical cord blood mesenchymal stem cell transplantation on intestinal ischemia-reperfusion injury in rats

  Objective: To investigate the effect of glutamine combined with cord blood mesenchymal stem cells (MSCs) transplantation on intestinal ischemia-reperfusion injury in rats.

  Methods: The umbilical cord blood mesenchymal stem cells were recovered and cultured in vitro before transplantation, and the fate of the umbilical cord blood mesenchymal stem cells after CM-DiI fluorescent labeling was observed. Eighty SD rats were randomly divided into normal control group, ischemia-reperfusion injury group, glutamine group, MSCs transplantation group and combination group, 15 in each group. The control group was given normal saline enema, and the injury group was given TNB (S ethanol dilution) enema. One hour after TNBS modeling, the glutamine group received 0.45 g/kg of glutamine into the tail vein, and the MSCs transplantation group received 1 hour of glutamine into the tail vein. ×1010/L umbilical cord blood mesenchymal stem cell suspension, in the combined group, 0.45 g/kg of glutamine + 1×1010/L umbilical cord blood mesenchymal stem cell suspension was infused into the tail vein. The contents of intestinal fatty acid binding protein (IFABP), interleukin-6 (IL-6) and superoxide dismutase (SOD) in the serum of rats in each group were detected by ELISA; Intestinal tissue water content; RT-PCR and Western blot were used to observe the mRNA and protein expressions of caspase-3, NF-kB and Bcl-2 in rat intestinal mucosal epithelial cells after glutamine combined with MSCs transplantation.

  RESULTS: Transplanted MSCs were observed to distribute in the intestinal mucosal lymphoid tissue and between glandular epithelial cells by fluorescence tracing, indicating that MSCs may be involved in the repair process of intestinal ischemia-reperfusion injury. Comparison of the changes of SOD, IFABP and IL-6 content in serum of rats in each group, the content of IFABP and IL-6 in serum of the injury group was significantly increased compared with the control group, while the glutamine group, the MSCs transplantation group and the combined group were compared with those in the glutamine group. Compared with the control group, the serum SOD content of the injury group was significantly reduced, while the glutamine group, the MSCs transplantation group and the combined group were significantly increased, and the combined group increased more than the control group. Significant (P<0.05). 1="" 3="" reperfusion="" p="">0.05). Compared with the control group, the mRNA and protein expressions of caspase-3 and NF-kB in intestinal mucosal epithelial cells in the injury group were significantly up-regulated, and the mRNA and protein expressions of Bcl-2 were significantly down-regulated (P<0.05). Compared with the glutamine group and the combination group, the mRNA and protein expressions of caspase-3 and NF-kB were significantly down-regulated, and the mRNA and protein expressions of Bcl-2 were significantly up-regulated (P<0.05). there="" was="" no="" difference="" between="" the="" glutamine="" group="" and="" mscs="" transplantation="" group.="" statistical="" p="">0.05), but the two groups were compared with the combined group, the difference was significant (P<0.05).

  Conclusion: Glutamine group and MSCs transplantation can significantly reduce the degree of intestinal ischemia-reperfusion injury in rats, which may reduce intestinal mucosal ischemia-reperfusion injury by inhibiting the expression of caspase-3 and NF-kB and promoting the expression of Bcl-2.