Glutamine and the bowel
Glutamine and the bowel
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DOI：
10.1093/jn/131.9.2505s
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发表时间：
2001-09-01
影响因子：
4.2
通讯作者：
Burrin, DG
中科院分区：
文献类型：
--
作者：
Reeds, PJ;Burrin, DG
自从Windmueller和Spaeth的开创性工作以来，谷氨酰胺对支持肠粘膜代谢功能的重要性已被普遍接受。然而，这一作用背后的机制仍然不清楚。本文探讨了以下几个问题：1）谷氨酰胺对肠道功能是必需的吗？2)这在多大程度上与其中间代谢有关？3)谷氨酰胺作为生物合成前体的重要性是什么？4)补充谷氨酰胺的营养混合物是否对患者的代谢或临床有益？作为该探索性研究的结果，得出了以下一般性结论：1）存在许多提示性的生化和生理证据，表明谷氨酰胺，尤其是全身性谷氨酰胺，支持肠粘膜系统的功能。2)尽管这种氨基酸在肠组织中广泛代谢，但大多数证据表明，如果谷氨酰胺确实在肠中发挥生理作用，则它与其中间代谢无关。3)另一方面，有证据表明粘膜细胞不仅利用细胞外谷氨酰胺，而且合成氨基酸。鉴于谷氨酰胺合成的抑制抑制粘膜细胞培养物的增殖和分化，这表明一些更微妙的调节作用。这一观点得到了谷氨酰胺将激活粘膜中与细胞周期进展相关的许多基因的证明的支持。4)尽管积累了大量的证据，谷氨酰胺的作用机制以及补充谷氨酰胺是否均匀有益于粘膜健康的问题充其量仍然是模棱两可的。
Since the pioneering work of Windmueller and Spaeth, the importance of glutamine to the support of intestinal mucosal metabolic function has become generally accepted. Nevertheless, the mechanisms underlying this role still remain obscure. This paper explores a number of questions: 1) Is glutamine essential for intestinal function? 2) To what extent does this relate to its intermediary metabolism? 3) What is the importance of glutamine as a biosynthetic precursor? 4) Is glutamine supplementation of the nutrient mixture presented to patients of any metabolic or clinical benefit? As a result of this exploratory exercise, the following general conclusions were reached: 1) Much suggestive biochemical and physiologic evidence exists that implies that glutamine, especially systemic glutamine, supports the function of the intestinal mucosal system. 2) Despite the extensive metabolism of this amino acid by the intestinal tissues, most evidence suggests that if glutamine does play a physiologic role in the bowel, it is not compellingly related to its intermediary metabolism. 3) There is, on the other hand, evidence that the mucosal cells not only utilize extracellular glutamine but synthesize the amino acid. Given that inhibition of glutamine synthesis inhibits both proliferation and differentiation of mucosal cell cultures, this suggests some more subtle regulatory role. This notion is supported by the demonstration that glutamine will activate a number of genes associated with cell cycle progression in the mucosa. 4) Despite the accumulated evidence, the mechanisms underlying glutamine's function and the question whether glutamine supplementation uniformly benefits mucosal health remain equivocal at best.