Manna Prasenjit, Das Joydeep, Sil Parames C
Department of Pediatrics, Louisiana State University Health Sciences Center, Shreveport, LA 71103, USA.
Curr Diabetes Rev. 2013 May;9(3):237-48. doi: 10.2174/1573399811309030005.
Amino acid supplementation is gaining acceptance as an important adjuvant therapy in the treatment of diabetes and its associated complications. Numerous studies in the literature report the impaired amino acid metabolism in diabetes and the beneficial effects of amino acids are positively correlated with the increase in plasma levels of those amino acids. Oxidative stress is known to play a major role in diabetic pathophysiology. Sulfur containing compounds are well known in the treatment of oxidative stress induced pathological disorders. Methionine, cysteine, and homocysteine are the three common sulfur containing amino acids. In addition, taurine, a sulfonic acid containing an amino group (amino sulfonic acid), is found in substantial amounts in mammalian tissues. Both experimental and clinical studies reported the modulatory effects of cysteine, N-acetyl cysteine, or compounds having cysteine moiety in the regulation of insulin secretion and plasma glucose levels. Taurine supplementation has been found to prevent the onset of diabetes mellitus in experimental models of both insulin dependent and insulin independent pathways. Recent reports suggest that the beneficial role of cysteine or taurine is mediated via their ability in reducing glycooxidation and preventing the generation of intracellular reactive intermediates. Studies with methionine or S-adinosyl methionine has been shown to increase mitochondrial DNA density in skeletal muscle, improve insulin sensitivity and prevent body weight gain. Homocysteine, on the other hand, is an emerging risk factor for cardiovascular disease and diabetic patients have higher levels of this sulfur containing amino acid. Supplementation with cysteine or taurine, however, was found to be effective in reducing plasma homocysteine levels. This review will discuss the role of sulfur containing amino acids in the regulation of hyperglycemia and in the development of its associated pathological dysfunctions.
补充氨基酸作为糖尿病及其相关并发症治疗中的一种重要辅助疗法正逐渐被接受。文献中的大量研究报告了糖尿病患者氨基酸代谢受损，且氨基酸的有益作用与这些氨基酸血浆水平的升高呈正相关。已知氧化应激在糖尿病病理生理过程中起主要作用。含硫化合物在治疗氧化应激诱导的病理紊乱方面广为人知。蛋氨酸、半胱氨酸和同型半胱氨酸是三种常见的含硫氨基酸。此外，牛磺酸是一种含氨基的磺酸（氨基磺酸），在哺乳动物组织中大量存在。实验和临床研究均报道了半胱氨酸、N-乙酰半胱氨酸或含有半胱氨酸部分的化合物在调节胰岛素分泌和血糖水平方面的调节作用。在胰岛素依赖和非胰岛素依赖途径的实验模型中，已发现补充牛磺酸可预防糖尿病的发生。最近的报告表明，半胱氨酸或牛磺酸的有益作用是通过它们降低糖氧化和防止细胞内反应性中间体产生的能力介导的。对蛋氨酸或S-腺苷蛋氨酸的研究表明，它们可增加骨骼肌中线粒体DNA密度，改善胰岛素敏感性并防止体重增加。另一方面，同型半胱氨酸是心血管疾病的一个新出现的危险因素，糖尿病患者体内这种含硫氨基酸水平较高。然而发现补充半胱氨酸或牛磺酸可有效降低血浆同型半胱氨酸水平。本综述将讨论含硫氨基酸在调节高血糖及其相关病理功能障碍发展中的作用。
