The Protective Effect of L-carnitine on Ionizing Radiation-induced Free Oxygen Radicals

Abstract

Ionizing radiation is known to generate reactive oxygen species (ROS) that can be removed by antioxidants.  L-carnitine, a natural component of mammalian tissue, is a necessary factor in the utilization of long-chain  fatty acids to produce energy. Furthermore it has been shown that L-carnitine is an antioxidant which has  a scavenger effect on ROS and a stabilizing effect on damaged cell membranes. The aim of the study was  to evaluate the potential protective effect of L-carnitine on radiation-induced free radicals in hamsters. Lcarnitine  was given by gavage at a dose of 50 mg/kg for 15 consecutive days before irradiation with a single  dose of 8 Gy. 24 h after radiation exposure, the hamsters were sacrificed and samples were taken from  blood and tissues, and the biochemical and histopatological determinations were carried out. In the irradiated  group, there were significant increases in plasma and liver malondialdehyde (MDA) with marked  reduction in glutathione (GSH) levels in the liver, compared with controls. In red blood cells, superoxide  dismutase (SOD) and catalase activities were also reduced. All these effects were reversed by L-carnitine.  In conclusion, L-carnitine with its antioxidant and free radical scavenging properties could play a modulatory  role against the cellular damage produced by free radicals induced by ionizing radiation.