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Background: Amino acids have been shown to stimulate insulin secretion and decrease glycated hemoglobin (A1C) in patients with Type 2 diabetes. In vitro, glycine reduces tumor necrosis factor (TNF)-α secretion and increases interleukin-10 secretion in human monocytes stimulated with lipopolysaccharide. The aim of this study was to determine whether glycine modifies the proinflammatory profiles of patients with Type 2 diabetes. Materials/subjects and methods: Seventy-four patients, with Type 2 diabetes were enrolled in the study. The mean age was 58.5 yr, average age of diagnosis was 5 yr, the mean body mass index was 28.5 kg/m2, the mean fasting glucose level was 175.5 mg/dl and the mean A1C level was 8%. They were allocated to one of two treatments, 5 g/d glycine or 5 g/d placebo, po tid, for 3 months. Results: A1 C levels of patients given glycine were significantly lower after 3 months of treatment than those of the placebo group. A significant reduction in TNF-receptor I levels was observed in patients given glycine compared with placebo. There was a decrease of 38% in the interferon (IFN)-γ level of the group treated with placebo, whereas that of the group treated with glycine increased up to 43%. These data showed that patients treated with glycine had a significant decrease in A1C and in proinflammatory cytokines and also an important increase of IFN-γ. Conclusion: Treatment with glycine is likely to have a beneficial effect on innate and adaptive immune responses and may help prevent tissue damage caused by chronic inflammation in patients with Type 2 diabetes.

A family‐based study has recently reported that a variant located in intron 10 of the gene MGEA5increases susceptibility to Type 2 Diabetes (T2D). We evaluated the distribution of this SNP in a sample of T2D patients (N= 271) and controls (N= 244) from Mexico City. The frequency of the T allele was higher in the cases (2.6%) than in the controls (1.8%). After adjusting for age, sex, BMI, education, and individual ancestry the odds ratio was 1.60 but the 95% confidence interval was wide and overlapped 1 (0.52–4.86, P‐value : 0.404). In order to characterize the distribution of the MGEA5‐14 polymorphism in the relevant parental populations, we genotyped this variant in European (and European Americans), West African, and Native American samples. The T‐allele was present at a frequency of 2.3% in Spain, 4.2% in European Americans, and 13% in Western Africans, but was absent in two Native American samples from Mexico and Peru. Given the low frequency of the T‐allele, further studies using large sample sizes will be required to confirm the role of this variant in T2D. Am. J. Hum. Biol. 19:593–596, 2007. © 2007Wiley‐Liss, Inc.