Beneficial effects of a long-term oral l-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patients

Pietro Lucotti, Emanuela Setola, Lucilla D. Monti, Elena Galluccio, Sabrina Costa, Emilia P. Sandoli, Isabella Fermo, Giovanni Rabaiotti, Roberto Gatti, PierMarco Piatti
2006 American Journal of Physiology. Endocrinology and Metabolism  
eficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulinresistant type 2 diabetic patients. Because chronic L-arginine supplementation improves insulin sensitivity and endothelial function in nonobese type 2 diabetic patients, the aim of this study was to evaluate the effects of a long-term oral L-arginine therapy on adipose fat mass (FM) and muscle free-fat mass (FFM) distribution, daily glucose levels, insulin
more » ... ity, endothelial function, oxidative stress, and adipokine release in obese type 2 diabetic patients with insulin resistance who were treated with a combined period of hypocaloric diet and exercise training. Thirty-three type 2 diabetic patients participated in a hypocaloric diet plus an exercise training program for 21 days. Furthermore, they were divided into two groups in randomized order: the first group was also treated with L-arginine (8.3 g/day), and the second group was treated with placebo. Although in the placebo group body weight, waist circumference, daily glucose profiles, fructosamine, insulin, and homeostasis model assessment index significantly decreased, L-arginine supplementation further decreased FM (P Ͻ 0.05) and waist circumference (P Ͻ 0.0001), preserving FFM (P Ͻ 0.03), and improved mean daily glucose profiles (P Ͻ 0.0001) and fructosamine (P Ͻ 0.03). Moreover, change in area under the curve of cGMP (second messenger of nitric oxide; P Ͻ 0.001), superoxide dismutase (index of antioxidant capacity; P Ͻ 0.01), and adiponectin levels (P Ͻ 0.02) increased, whereas basal endothelin-1 levels (P Ͻ 0.01) and leptin-to-adiponectin ratio (P Ͻ 0.05) decreased in the L-arginine group. Long-term oral L-arginine treatment resulted in an additive effect compared with a diet and exercise training program alone on glucose metabolism and insulin sensitivity. Furthermore, it improved endothelial function, oxidative stress, and adipokine release in obese type 2 diabetic patients with insulin resistance. obesity; type 2 diabetes; endothelium; lean body mass; L-arginine TYPE 2 DIABETES AND OBESITY are frequently clustered with other metabolic conditions such as insulin resistance, hypertriglyceridemia, low HDL cholesterol, hypertension, visceral obesity, and deregulated adipokine release, characterizing the metabolic syndrome with a high risk for the development of cardiovascular disease (19) . In this context, an exercise pro-
doi:10.1152/ajpendo.00002.2006 pmid:16772327 fatcat:g72iqckbsbc3bequmflqktc3mi