Effect of oral L-carnitine administration on insulin sensitivity and lipid profile in type 2 diabetes mellitus patients

Aim: It was the aim of this study to evaluate the effect of oral L-carnitine administration on insulin sensitivity and lipid profile in subjects with type 2 diabetes mellitus. Subjects and Methods: A randomized, double-blind, placebo-controlled clinical trial was carried out in 12 subjects with type 2 diabetes. Six subjects received L-carnitine 1 g orally 3 times a day before meals for a period of 4 weeks. Six other individuals took a placebo for the same period of time, as the control group. Before and after the intervention, insulin sensitivity and the lipid profile were estimated. To assess insulin sensitivity, the euglycemic-hyperinsulinemic clamp technique was performed. Wilcoxon's signed rank and the Mann-Whitney U test were used for the statistical analyses. Results: There were no significant differences in basal clinical characteristics between the 2 groups. Insulin sensitivity and the basal lipid profile were similar. There were no significant changes in either group after the intervention in insulin sensitivity (3.2 +/- 1.2 vs. 4.5 +/- 1.7 mg/kg/min, p = 0.115, and 3.5 +/- 0.6 vs. 3.5 +/- 0.4 mg/kg/min, p = 0.917, for the placebo and L-carnitine groups, respectively) and in lipid profile. Conclusion: L-Carnitine orally administered for a period of 4 weeks did not modify insulin sensitivity or the lipid profile. Copyright (C) 2008 S. Karger AG, Basel.