Effect of 3-month L-arginine supplementation on insulin resistance and tumor necrosis factor activity in patients with visceral obesity.

K Musialik, J Suliburska, P Bogdanski, K Grabanska, A Cieslewicz, A Skoluda, A Jablecka

Journal: European review for medical and pharmacological sciences 2012;16(6):816-23

PMID: 22913215

Abstract

BACKGROUND

The role of tumor necrosis factor alpha (TNF-alpha), one of the adipose tissue products, in the pathogenesis of insulin resistance is well-documented. Many recent studies have shown beneficial influence of L-arginine supplementation on cardiovascular system. However, molecular mechanisms of its positive actions are not fully elucidated.

AIM

The aim of the study was to evaluate the influence of L-arginine supplementation on tumor necrosis factor alpha, insulin resistance and selected anthropometric and biochemical parameters in patients with visceral obesity.

PATIENTS AND METHODS

60 patients with visceral obesity were randomly assigned to either receive 9 g of L-arginine or placebo for 3 months. 20 healthy lean subjects were used as control. Selected anthropometrical measurements and blood biochemical analyses were performed at baseline and after 3-months. TNF-alpha and its soluble receptor 2 (sTNFR2) were assessed in both treated groups. Insulin resistance in the participants was evaluated according to the homeostasis model assessment-insulin resistance (HOMA-IR) protocol.

RESULTS

The concentration of insulin, TNF-a and sTNFR2 and HOMA-IR level in both obese groups significantly exceeded these observed in the control. Basal TNF-alpha and sTNFR2 concentrations were positively correlated with basal body mass index (BMI), waist circumference, percent of body fat and HOMA-IR. We found that 3-month L-arginine supplementation resulted in significant decrease of HOMA-IR and insulin concentration. Only insignificant tendency to decrease of TNF-alpha and sTNFR2 was observed.

CONCLUSIONS

Our results confirm TNF-alpha role in the complex pathogenesis of insulin resistance in patients with visceral obesity. 3-months L-arginine supplementation in a dose of 9 g improves insulin sensitivity in patients with visceral obesity with no impact on tumor necrosis factor alpha concentration.

Address: Department of Internal Medicine, Metabolic Disorders and Hypertension, Poznan University of Medical Sciences, Poznan, Poland. [email protected]

MeSH Terms: Adult, Arginine, Blood Pressure, Dietary Supplements, Female, Humans, Insulin, Insulin Resistance, Male, Middle Aged, Obesity, Abdominal, Receptors, Tumor Necrosis Factor, Type II, Tumor Necrosis Factor-alpha