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.

Abstract

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 sensitivity, 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 < 0.05) and waist circumference (P < 0.0001), preserving FFM (P < 0.03), and improved mean daily glucose profiles (P < 0.0001) and fructosamine (P < 0.03). Moreover, change in area under the curve of cGMP (second messenger of nitric oxide; P < 0.001), superoxide dismutase (index of antioxidant capacity; P < 0.01), and adiponectin levels (P < 0.02) increased, whereas basal endothelin-1 levels (P < 0.01) and leptin-to-adiponectin ratio (P < 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.

• Authors: Pietro Lucotti, Emanuela Setola, Lucilla D Monti, Elena Galluccio, Sabrina Costa, Emilia P Sandoli, Isabella Fermo, Giovanni Rabaiotti, Roberto Gatti, PierMarco Piatti
• Journal: American journal of physiology. Endocrinology and metabolism (Am J Physiol Endocrinol Metab) Vol. 291 Issue 5 Pg. E906-12 (Nov 2006) ISSN: 0193-1849 [Print] United States
• PMID: 16772327 (Publication Type: Journal Article, Randomized Controlled Trial)

Chemical References

• Blood Glucose
• Insulin
• Triglycerides
• Fructosamine
• Arginine

Topics

• Administration, Oral
• Arginine (administration & dosage)
• Blood Glucose (metabolism)
• Blood Pressure
• Body Weight (drug effects)
• Combined Modality Therapy
• Diabetes Mellitus, Type 2 (diet therapy, drug therapy)
• Diet, Reducing
• Energy Intake
• Exercise
• Female
• Fructosamine (blood)
• Humans
• Insulin (blood)
• Insulin Resistance
• Male
• Middle Aged
• Obesity (diet therapy, drug therapy)
• Triglycerides (blood)