Effects Of L-Carnitine On Liver Injury In Rats And Its Impact On Blood Lipids

Objective: To explore mechanisms of anti oxidant activity of L-carnitine on liver injury and the impact of L-carnitine on serum lipid levels in rats. Methods: Ninty normal male Wister rats were selected and randomly classified into the blank control group (n=30), the placebo group (n=30) and the L-carnitine group (n=30). The rats in the L-carnitine group and the placebo group were intraperitoneally injected with endotoxin lipopolysaccharide at 0.1 mg/kg. Apart from that, those in the L-carnitine group also received concomitant L-carnitine at 1 g/kg by an intragastric route, while those in the placebo group were given equal amounts of normal saline by an intragastric route. Those in the blank control group were administered equal amounts of normal saline. The rats in the three groups were compared in the liver injury indicators, antioxidant-related indicators, inflammatory cytokines, and serum lipid content. Results: Compared with the blank control group, the serum aspartate aminotransferase (AST), alanine transaminase (ALT), malonialdehyde (MDA), low-density lipoprotein cholesterol (LDL-C), tetracycline (TC) and triglyceride (TG) levels in rats of the L-carnitine group and the placebo group were significantly elevated. Serum high-density lipoprotein cholesterol (HDL-C), superoxide dismutase (SOD), and and glutathione peroxidase (GSH-Px) levels were reduced. Nitric oxide (NO) content, nitric oxide synthase (NOS) activity, interleukine-6 (IL-6), interleukine-1 beta (IL-1 beta), and tumor necrosis factor-alpha (TNF-alpha) levels in hepatic tissue were markedly enhanced in rats of the L-carnitine group and the placebo group (all P<0.001). Compared to the rats in the placebo group, those in the L-carnitine group showed significantly lower serum AST, ALT, MDA, LDL-C, TC, and TG levels, considrably elevated serum HDL-C, SOD, and GSH-px levels, and reduced NO contents, NOS activity, IL-6, IL-1 beta, and TNF-alpha levels in hepatic tissue (all P<0.001). Conclusion: L-carnitine exerts a protective effect on endotoxin lipopolysaccharide-induced liver injury, and its protective mechanisms are associated with its anti-oxidant activity and reduced levels of inflammatory cytokines.