Dose-dependent lipotropic effect of carnitine in chronic alcoholic rats

The objective of this study was to determine if the lipotropic effect of supplementary DL-carnitine was dose dependent. Male Sprague-Dawley rats were fed for 45 d a liquid ethanol diet in which 36% of the total energy was derived from ethanol. The ethanol diet, containing 1.27 g L-carnitine per g of the diet, was fed as such or was supplemented with 0.1%, 0.4%, 0.8%, 1.2%, or 1.6% (wt/wt) DL-carnitine. Results showed a definite inverse relationship between the concentrations of lipids and those of carnitine fractions in both plasma and liver. The concentrations of total lipids and triglycerides were significantly lower with increasing levels of supplementary carnitine, whereas those of carnitine fractions were significantly higher than in controls up to 0.8% supplemental carnitine. The changes in the plasma and hepatic concentrations of various classes of lipid and carnitine were inversely related and were found to be progressive up to 0.8% DL-carnitine supplementation. Therefore, it was concluded that the lipotropic effect of dietary carnitine is dose dependent, and that the optimal supplementary level is 0.8% DL-carnitine.