Ockenga J, Borchert K, Stüber E, Lochs H, Manns M P, Bischoff S C
Department of Gastroenterology, Hepatology and Endocrinology, Medical School of Hannover, Germany.
Eur J Clin Nutr. 2005 Nov;59(11):1302-9. doi: 10.1038/sj.ejcn.1602243.
Studies in animal models of inflammatory bowel disease (IBD) suggest that supplementation of total parenteral nutrition with glutamine (gln), a conditionally essential amino acid in catabolic conditions, increases gln plasma concentrations, reduces intestinal damage, improves nitrogen balance and may improve the course of the disease. However, human data supporting this assumption are missing.
A total of 24 consecutive patients with an acute exacerbation of IBD (19 Crohn's disease; five ulcerative colitis) and scheduled for total parenteral nutrition (TPN) (>7 days) were randomised. Parallel to a standardised anti-inflammatory therapy, the patients received either a TPN with 1.5 g/kg body weight of a standard amino acid or an isonitrogenic, isocaloric TPN with 1.2 g/kg body weight of a standard amino acid and 0.3 g/kg L-alanine-L-glutamine. Primary end points were gln plasma concentrations and intestinal permeability assessed by urinary lactulose and D-xylose ratio.
Gln plasma levels did not differ significantly in either group throughout the study. Intestinal permeability did not change within 7 days either with or without gln supplementation (Delta-lactulose/xylose ratio: 0.01+/-0.05 (gln+) vs 0.02+/-0.1 (gln-)). The observed changes in inflammatory and nutritional parameters, and also disease activity, length of TPN and hospital stay, were independent of glutamine substitution. Five (41%) patients in the gln+ group and three (25%) patients in the gln- group needed surgical intervention.
Although limited by the sample size, these results do not support the hypothesis that glutamine substitution has an obvious biochemical or clinical benefit in patients with active IBD scheduled for total parenteral nutrition.
炎症性肠病（IBD）动物模型研究表明，在分解代谢状态下作为条件必需氨基酸的谷氨酰胺（gln）补充到全肠外营养中，可提高血浆谷氨酰胺浓度，减轻肠道损伤，改善氮平衡，并可能改善疾病进程。然而，缺乏支持这一假设的人体数据。
共有24例连续的IBD急性加重期患者（19例克罗恩病；5例溃疡性结肠炎）计划接受全肠外营养（TPN）（>7天）并被随机分组。在标准化抗炎治疗的同时，患者接受含1.5 g/kg体重标准氨基酸的TPN或含1.2 g/kg体重标准氨基酸和0.3 g/kg L-丙氨酰-L-谷氨酰胺的等氮、等热量TPN。主要终点是通过尿乳糖和D-木糖比率评估的血浆谷氨酰胺浓度和肠道通透性。
在整个研究过程中，两组的血浆谷氨酰胺水平均无显著差异。无论是否补充谷氨酰胺，肠道通透性在7天内均未改变（乳糖/木糖比率变化：谷氨酰胺补充组为0.01±0.05，未补充组为0.02±0.1）。观察到的炎症和营养参数变化以及疾病活动度、TPN时长和住院时间均与谷氨酰胺替代无关。谷氨酰胺补充组有5例（41%）患者和未补充组有3例（25%）患者需要手术干预。
尽管受样本量限制，但这些结果不支持谷氨酰胺替代对计划接受全肠外营养的活动性IBD患者有明显生化或临床益处这一假设。
