Improvement of insulin resistance via increase of GLUT4 and PPARγ in metabolic syndrome-induced rats treated with omega-3 fatty acid or l-carnitine

Abstract

Background: Frequent consumption of fructose and saturated fatty acids increase risk of metabolic syndrome (MS). Features of MS include insulin resistance, dyslipidemia, visceral obesity, and hypertension. The aim of this study was to investigate the role of omega-3 and l-carnitine in ameliorating features of MS.

Methods: MS was induced in rats by high-fructose high-fat fed diet for 8 weeks. They were randomly divided into five groups: normal control, MS control group treated with saline, MS groups given omega-3 (260 mg/kg), l-carnitine (200 mg/kg), or metformin (100 mg/kg) daily for 4 weeks. Body weight, relative organ weight, glucose, insulin, adiponectin, and lipid profiles were estimated. Also glucose transporter 4 (GLUT4) content and peroxisome proliferator-activated receptor-gamma (PPARγ) protein expressions were determined.

Results: Omega-3 and l-carnitine caused decrease in both MS-induced increase in body weight and glucose similar to metformin. They reduced insulin level and resistance with increased adiponectin, and correction of MS-induced hyperlipidemia. Drugs also increased GLUT4 and PPARγ protein expression compared with MS control group.

Conclusion: Omega-3 and l-carnitine improve features of MS via increased GLUT4 and PPARγ expression.

Keywords: insulin resistance; l-carnitine; lipid; metabolic syndrome; omega-3.