Effects of vitamin C and L-carnitine on lipid profile and oxidative stress parameters in the brain of fasted and refed rats
The roles of vitamin C and L-carnitine on lipid profile and oxidative stress parameters in the brain of rats during fasting and re-feeding were investigated. Sixty male Sprague-Dawley rats (170-180 g) were divided into four groups of control, fasting, fasting + vitamin C and fasting + L-carnitine. The test groups were further divided into recovery 1 (24 hours following a fast) and recovery 2 (72 hours following a fast). Rats were fasted in individualized cages but were allowed free water intake. The fasted rats were re-fed after the fast and parameters were obtained for indices of lipid profile and oxidative stress on days one and three of recovery. Total Cholesterol levels were increased during fasting in vitamin C and L-carnitine treated rats but these increases were abolished on day three of recovery (p<0.05). Triglycerides and LDL were increased in L-carnitine treated rats on day 1 of recovery while HDL levels were unchanged during fasting but decreased during recovery days 1 and 3 in both fasted and treated rats. There was an increase in MDA levels in the brain samples of fasted rats during fasting. However, no changes in the activity of the oxidative enzymes; SOD, GSH and CAT were found. The findings suggest that oxidative status was slightly perturbed during fasting in fasted rats without supplementation. Also, increased cholesterol levels during fasting in treated rats which was abolished during re-feeding portrays that the increased cholesterol during fasting might be due to the actions of vitamin C and L-carnitine on β-oxidation of fatty acids during fasting.
Keywords: Vitamin C, L-carnitine, Lipid profile, Oxidative stress, Fasting, Re-feeding