Neurobehavioral effects of l-carnitine and its ability to modulate genotoxicity and oxidative stress biomarkers in mice

l-Carnitine, a natural vitamin-like compound supplied to the body by biosynthesis and dietary sources, has been shown to exert beneficial effects in disorders affecting cardiovascular, urinary, and nervous systems. However, the paucity of data on its effects does not guarantee the safe use of l-carnitine as a nutritional supplement, and further pre-clinical studies are required to assess toxicological aspects. The present study evaluated the effects of l-carnitine (10, 50 or, 100 mg/kg) in mice, in the open field test. Also, lipoperoxidation was assessed measuring thiobarbituric acid reactive substances (TBARS) and genotoxic/antigenotoxic activities were evaluated using the comet assay in several tissues. l-Carnitine 50 mg/kg impaired exploration, though with no effects on habituation to a novel environment. l-Carnitine increased TBARS in the brain and liver tissues, but it did not induce genotoxicity in any tissue. In ex vivo comet assay, a decrease in DNA damage in the blood and liver tissues was observed, while the opposite occurred in the brain tissue. In conclusion, l-carnitine may increase lipid peroxidation, though without inducing genotoxic effects, protect DNA against endogenous and induced oxidative damages in blood and liver; however, l-carnitine impaired exploratory behavior and increased the vulnerability of the brain tissue to oxidative stress, suggesting that the excessive consumption of l-carnitine may promote deleterious effects on the central nervous system.