Background Aspartame (ASP) is used for treatment of obesity and diabetes mellitus. This study was designed to illustrate the biochemical responses and histopathological alterations besides the genotoxicity of ASP alone or with l-carnitine (LC) in the liver of rats. Methods Animals were separated into six groups: control, lower dose of ASP (ASP-LD; 75 mg/kg), higher dose of ASP (ASP-HD; 150 mg/kg), l-carnitine (LC; 10 mg/kg), ASP-LD plus LC, and ASP-HD plus LC. Treatment was carried out orally for 30 consecutive days. Results ASP raised the activity of some enzymes of liver markers and disturbed the lipid profile levels. The hepatic reduced glutathione (GSH) levels, the marker enzymes of antioxidant activities, were obviously diminished, and, possibly, the lipid peroxidation, C-reactive protein, and interleukins levels were increased. ASP significantly increased the DNA deterioration in comparison with the control in a dose-dependent manner. LC prevented ASP-induced liver damage as demonstrated by the enhancement of all the above parameters. Results of histopathological and electron microscopic examination proved the biochemical feedback and the improved LC effect on liver toxicity. Conclusions The co-treatment of LC showed different improvement mechanisms against ASP-induced liver impairment. So, the intake of ASP should be regulated and taken with LC when it is consumed in different foods or drinks to decrease its oxidative stress, histopathology, and genotoxicity of liver.
Keywords: DNA; antioxidant enzymes; aspartame; histology; l-carnitine; oxidative biomarkers; transmission electron microscopy.