Li Y S, Li J S, Jiang J W, Liu F N, Li N, Qin W S, Zhu H
Department of Surgery, Jinling Hospital, Nanjing, 210002, China.
J Surg Res. 1999 Mar;82(1):106-11. doi: 10.1006/jsre.1998.5525.
Improvements in immunosuppression, operative procedure, and posttransplant management have made clinical small bowel transplantation (SBT) feasible. Ischemia and reperfusion injury, total parenteral nutrition (TPN), and devoidment of enteral feeding lead to graft atrophy, gut barrier dysfunction, and bacterial translocation. Glutamine (Gln) is the principal fuel for the enterocyte. The influence of Gln dipeptide-supplemented TPN, especially long-term TPN, on intestinal graft permeability and bacterial translocation is not clear following SBT in the large animal model. Therefore, we studied the effect of glutamine dipeptide, glycyl-glutamine (Gly-Gln), on bacterial translocation following SBT in the pig, which has a physiology similar to humans.
The outbred pigs underwent segmental small bowel autotransplantation and were divided into two groups. In the STPN group (n = 5), the animal received standard TPN devoid of Gly-Gln for 28 days. In the GTPN group (n = 5), the animal received isonitrogenous (0.3 g/kg.day) and isocaloric (33 kcal/kg.day) TPN solution with 2% Gly-Gln for 28 days.
At the end of the experiment, Gly-Gln-enriched TPN could maintain the plasma Gln level, graft mucosal Gln and protein concentrations, and skeletal muscle Gln and protein concentrations. Gly-Gln-enriched TPN significantly decreased the bacterial number of mesenteric lymph nodes in the liver and spleen and intestinal permeability to 99mTc-DTPA. There were no significant differences in body weight gain.
The Gly-Gln-enriched long-term TPN may maintain the plasma Gln level, mucosal and muscle Gln, and protein concentrations and attenuate the intestinal permeability to 99mTc-DTPA and bacterial translocation following small bowel transplantation in the pig.
免疫抑制、手术操作及移植后管理的改善已使临床小肠移植(SBT)成为可能。缺血再灌注损伤、全胃肠外营养(TPN)及缺乏肠内营养会导致移植物萎缩、肠屏障功能障碍及细菌易位。谷氨酰胺(Gln)是肠上皮细胞的主要能量来源。在大型动物模型中,补充谷氨酰胺二肽的TPN,尤其是长期TPN,对小肠移植后肠道移植物通透性及细菌易位的影响尚不清楚。因此,我们在生理机能与人类相似的猪身上研究了谷氨酰胺二肽(甘氨酰谷氨酰胺,Gly-Gln)对小肠移植后细菌易位的影响。
选用远交群猪进行节段性小肠自体移植,并分为两组。在标准TPN组(n = 5)中,动物接受不含Gly-Gln的标准TPN 28天。在甘氨酰谷氨酰胺TPN组(n = 5)中,动物接受含2% Gly-Gln的等氮(0.3 g/kg·天)和等热量(33 kcal/kg·天)TPN溶液28天。
实验结束时,富含Gly-Gln的TPN可维持血浆Gln水平、移植物黏膜Gln和蛋白质浓度以及骨骼肌Gln和蛋白质浓度。富含Gly-Gln的TPN显著降低了肝脏、脾脏肠系膜淋巴结的细菌数量以及肠道对99mTc-DTPA的通透性。体重增加方面无显著差异。
富含Gly-Gln的长期TPN可能维持血浆Gln水平、黏膜和肌肉中的Gln及蛋白质浓度,并减轻猪小肠移植后肠道对99mTc-DTPA的通透性和细菌易位。