Sido Bernd, Seel Cornelia, Hochlehnert Achim, Breitkreutz Raoul, Dröge Wulf
Department of Surgery, Ruprecht-Karls University, Heidelberg, Germany.
Dig Dis Sci. 2006 Dec;51(12):2170-9. doi: 10.1007/s10620-006-9473-x. Epub 2006 Nov 1.
Intestinal glutamine utilization is integral to mucosal regeneration. We analyzed the systemic and intestinal glutamine status in Crohn's disease (CD) and evaluated the therapeutic effect of glutamine supplementation in an animal model of ileitis. In CD, glutamine concentrations were decreased systemically and in noninflamed and inflamed ileal/colonic mucosa. Mucosal glutaminase activities were depressed in the ileum independent of inflammation but were not different from controls in the colon. In experimental ileitis, oral glutamine feeding prevented macroscopic inflammation, enhanced ileal and colonic glutaminase activities above controls, and normalized the intestinal glutathione redox status. However, glutamine supplementation enhanced myeloperoxidase activity along the gastrointestinal tract and potentiated lipid peroxidation in the colon. In conclusion, glutamine metabolism is impaired in CD. In experimental ileitis, glutamine supplementation prevents inflammatory tissue damage. In the colon, however, which does not use glutamine as its principal energy source, immune enhancement of inflammatory cells by glutamine increases oxidative tissue injury.
肠道谷氨酰胺利用对于黏膜再生至关重要。我们分析了克罗恩病（CD）患者的全身及肠道谷氨酰胺状态，并在回肠炎动物模型中评估了补充谷氨酰胺的治疗效果。在CD患者中，全身以及未发炎和发炎的回肠/结肠黏膜中的谷氨酰胺浓度均降低。回肠黏膜谷氨酰胺酶活性不受炎症影响而降低，但结肠中的酶活性与对照组无差异。在实验性回肠炎中，口服谷氨酰胺可预防肉眼可见的炎症，使回肠和结肠谷氨酰胺酶活性高于对照组，并使肠道谷胱甘肽氧化还原状态恢复正常。然而，补充谷氨酰胺会增强胃肠道的髓过氧化物酶活性，并加剧结肠中的脂质过氧化。总之，CD患者的谷氨酰胺代谢受损。在实验性回肠炎中，补充谷氨酰胺可预防炎症组织损伤。然而，在不以谷氨酰胺作为主要能量来源的结肠中，谷氨酰胺增强炎症细胞的免疫反应会增加氧化组织损伤。
