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Author Spotlight: In Vivo Assessment of Thyroid Hormone Disruption Using the THAI Mouse Model
Published on: October 6, 2023
Dose-dependent protective effect of L-carnitine on oxidative stress in the livers of hyperthyroid rats
Serap Yildirim1, Abdulkadir Yildirim2, Senol Dane3
1Department of Physiology, Faculty of Medicine, Ataturk University, Erzurum, Turkey.
Objective:
The present study was designed to investigate the dose-dependent protective effect of L-carnitine (LC) on thyroid hormone-induced oxidative stress in rat liver tissue.
Materials And Methods:
Twenty-one male Sprague Dawley rats were divided into four groups: control, hyperthyroidism, hyperthyroidism plus L-carnitine 100, and hyperthyroidism plus L-carnitine 500. Hyperthyroidism was induced in rats by injecting 250 μg of L-thyroxine/kg body weight/day for twenty consecutive days. The activities of catalase (CAT), glutathione peroxidase (GPX) and myeloperoxidase (MPO) and the level of malondialdehyde (MDA) were measured in liver homogenates.
Results:
The liver CAT, GPX and MPO activities were significantly lower in the hyperthyroid rats than in the control group. Treating hyperthyroid rats with both low-dose (100 mg/kg) and high-dose (500 mg/kg) L-carnitine for 10 days resulted in a marked increase in the activities of the antioxidant enzymes in the liver tissue.
Conclusion:
The present study indicates that the low-dose L-carnitine application was sufficient to prevent L-thyroxine-induced oxidative stress in rat livers.
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