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.

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.

Insulin resistance and endothelial function are improved after folate and vitamin B12 therapy in patients with metabolic syndrome: relationship between homocysteine levels and hyperinsulinemia.

Objective: The purpose of this study was (a) to study whether a folate and vitamin B12 treatment, aimed at decreasing homocysteine levels, might ameliorate insulin resistance and endothelial dysfunction in patients with metabolic syndrome according to the National Cholesterol Education Program-Adult Treatment Panel-III criteria and (b) to evaluate whether, under these metabolic conditions, there is a relationship between hyperhomocysteinemia and insulin resistance.

Design And Methods: A double-blind, parallel, identical placebo-drug, randomized study was performed for 2 months in 50 patients. Patients were randomly allocated to two groups.

Myocardial insulin resistance associated with chronic hypertriglyceridemia and increased FFA levels in Type 2 diabetic patients.

We evaluated the influence of chronic hypertriglyceridemia and endothelial dysfunction on myocardial glucose uptake (MGU) in Type 2 diabetic patients without coronary heart disease. Patients were divided into two groups according to fasting triglyceride (TG) levels: 5.4 +/- 1.

Alterations in nitric oxide/cyclic-GMP pathway in nondiabetic siblings of patients with type 2 diabetes.

In this study, we have compared resistance to insulin-mediated glucose disposal and plasma concentrations of nitric oxide (NO) and cyclic-GMP in healthy volunteers with (n = 35) or without (n = 27) at least one sibling and one parent with type 2 diabetes. The 62 volunteers were further divided into groups of those with normal glucose tolerance or impaired glucose tolerance. Insulin-mediated glucose disposal was quantified by determining the insulin sensitivity index (ISI) in response to a low-dose, constant infusion of insulin (25 mU/kg x h) and glucose (4 mg/kg x min) for 150 min.

Effects of endothelin-1 and nitric oxide on glucokinase activity in isolated rat hepatocytes.

To test the hypothesis that endothelin-1 (ET-1) and nitric oxide (NO) influence glucokinase (GK) activity in an opposite manner, we evaluated the effects of ET-1, L-NAME, an inhibitor of NO synthase, and L-arginine, a substrate for NO synthase, on GK activity and glycogen content in isolated rat hepatocytes. Moreover, to understand the receptor involved in the process, the effects of BQ 788, a specific antagonist of ETB receptor, and PD 142893, an antagonist of ETA-ETB receptors, were also evaluated. GK activity, cyclic guanosine monophosphate (cGMP), and glycogen intracellular content were measured on isolated hepatocytes, while glucose levels and NO as NO2-/NO3- were determined in the medium.