Glycine treatment decreases proinflammatory cytokines and increases interferon-γ in patients with Type 2 diabetes

• Published in: Journal of endocrinological investigation Vol. 31; no. 8; pp. 694 - 699
• Main Authors: Cruz, M., Maldonado-Bernal, C., Mondragón-Gonzalez, R., Sanchez-Barrera, R., Wacher, N. H., Carvajal-Sandoval, G., Kumate, J.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2008
• Subjects: Aged; Cytokines - blood; Cytokines - metabolism; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - drug therapy; Diabetes Mellitus, Type 2 - metabolism; Endocrinology; Female; Glycine - administration & dosage; Glycine - pharmacology; Glycine - therapeutic use; Humans; Hypoglycemic Agents - administration & dosage; Inflammation Mediators - blood; Inflammation Mediators - metabolism; Interferon-gamma - blood; Interferon-gamma - metabolism; Interleukin-6 - blood; Male; Medicine; Medicine & Public Health; Metabolic Diseases; Middle Aged; Original Articles; Placebos; Resistin - blood; Type 2 diabetes; glycine treatment; proinflammatory cytokines; A1C; glucose metabolism
• ISSN: 0391-4097; 1720-8386
• DOI: 10.1007/BF03346417

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/m 2 , 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.