Doxorubicin toxicity can be ameliorated during antioxidant L-carnitine supplementation

Doxorubicin is an antibiotic broadly used in treatment of different types of solid tumors. The present study investigates whether L-carnitine, antioxidant agent, can reduce the hepatic damage induced by doxorubicin. Male Wistar albino rats were divided into six groups: group 1 was intraperitoneal injected with normal saline for 10 consecutive days; group 2, 3 and 4 were injected every other day with doxorubicin (3 mg/kg, i.p.), to obtain treatments with cumulative doses of 6, 12 and 18 mg/kg. The fifth group was injected with L-carnitine (200 mg/kg, i.p.) for 10 consecutive days and the sixth group was received doxorubicin (18 mg/kg) and L-carnitine (200 mg/kg). High cumulative dose of doxorubicin (18 mg/kg) significantly increases the biochemical levels of alanine transaminase, alkaline phosphatase, total bilirubin, thiobarbituric acid reactive substances (TBARs), total nitrate/nitrite (NOx) p < 0.05 and decrease in glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione-s-transferase (GST), glutathione reductase (GR) and catalase (CAT) activity p < 0.05. The effect of doxorubicin on the activity of antioxidant genes was confirmed by real time PCR in which the expression levels of these genes in liver tissue were significantly decrease compared to control p < 0.05. Interestingly, L-carnitine supplementation completely reversed the biochemical and gene expression levels induced by doxorubicin to the control values. In conclusion, data from this study suggest that the reduction of antioxidant defense during doxorubicin administration resulted in hepatic injury could be prevented by L-carnitine supplementation by decreasing the oxidative stress and preserving both the activity and gene expression level of antioxidant enzymes.