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.

Oral L-arginine administration improves anthropometric and biochemical indices associated with cardiovascular diseases in obese patients: A randomized, single blind placebo controlled clinical trial

“…The present study observed a significant decrease in the MDA level. Previous studies have reported similar results with L-arginine supplementation, including improved antioxidant statuses indicated by an increased total antioxidant status (33), glutathione and superoxide dismutase levels, (19) and circulating plasma ascorbic acid levels, all of which have been shown to protect against peroxidative lipid damage (34); therefore, increased cell membrane permeability and decreased lipid oxidation lead to decreased MDA levels (35). We recommend additional clinical trials with larger sample sizes and longer intervention periods to facilitate a better understanding of the role of L-arginine supplementation for weight management in obese people at risk of CVDs.…”

Effect of <i>L</i>-Arginine and Selenium Added to a Hypocaloric Diet Enriched with Legumes on Cardiovascular Disease Risk Factors in Women with Central Obesity: A Randomized, Double-Blind, Placebo-Controlled Trial

“…Studies on the effects of such supplementation in females with central obesity are lacking. Oral consumption of high doses of L -arginine has been shown to reduce abdominal adipose tissue in animal models [4,5,6] and to reduce central obesity in subjects with type 2 diabetes mellitus [7]. …”

Enhancing eNOS activity with simultaneous inhibition of IKKβ restores vascular function in Ins2Akita+/− type-1 diabetic mice

“…25 In STZ-treated type-1 diabetic mice, endothelial cell activation and inflammation was abolished by L-arginine treatment. However, the available literature on the beneficial effects of L-arginine is inconclusive mainly due to inconsistent concentrations of L-arginine used and the duration of treatment.…”