Effects of different doses of tilmicosin on some biochemical parameters and antioxidant status in serum and cardiac tissues in mice

The objective of this study was to evaluate effects of different doses of tilmicosin on serum and cardiac creatine kinase (CK), creatine kinase-MB (CK-MB), total sialic acid (TSA), and antioxidant status, including the levels of glutathione (GSH) and malondialdehyde (MDA), to determine its cardiotoxic effects and alterations in antioxidant status. Fifty Balb/C mice were divided into 5 groups. The control group received saline. Groups 2, 3, 4, and 5, were injected with a single dose of tilmicosin at 10, 30, 50, and 70 mg/kg, respectively. No differences was found in serum CK and CKMB activities as well as TSA, GSH, and MDA concentrations at doses of 10 and 30 mg/kg of tilmicosin compared to control. However, doses of 50 and 70 mg/kg of the antibiotic resulted in a significant increase in serum CK and CK-MB activities, TSA and MDA concentrations, with significant decrease in GSH level compared to control group and groups 2 and 3. Increased cardiac MDA, and decreased GSH concentrations were found in groups 4 and 5, compared to other groups, whereas there was dose dependent-increase in CK, CK-MB, and TSA level at 30 mg/kg, and higher doses compared to control and group 2. Tilmicosin administration at doses of 50 and 70 mg/kg appears to alter selected cardiac enzymes and TSA concentration indicating its cardiotoxic and strong prooxidant effect in mice.