Thymoquinone reduces methotrexate-induced heart damage: a histopathological study in rats

Purpose: The study aimed to evaluate the effect of thymoquinone on cardiac tissue in MTX-induced cardiac toxicity in rats with various parameters. Materials and Methods: Group I (n:8) was administered intraperitoneal saline for 10 days. Intraperitoneal olive oil was applied to Group II (n:8) for 10 days. Group III (n:8) was administered a single dose of 20 mg/kg Methotrexate (MTX) (500 mg/20 ml) intraperitoneally on the 1st day of the experiment. Since Methotrexate was in liquid form, no solvent was used. Group IV (n:8) received 10 mg/kg Thymoquinone (THQ) intraperitoneally for 10 days. Group V (n:8) (MTX: (20 mg/kg single dose intraperitoneally on the 1st day); THQ: 10mg/kg i.p. administered for 10 days. At the end of the experimental period, the rats were sacrificed for analysis of heart tissue. The structure of heart tissue was evaluated by haematoxylin-eosin staining. Immunohistochemically, connexin-43, HSP90, and HIF-1α antibodies were stained. The results were analysed statistically. Results: According to our results, thymoquinone has a positive effect on the expression of Cx43, one of the proteins providing transmission in the intercalary discs, HSP90, one of the chaperones in the cell, and HIF-1α expression against MTX toxicity and provides a significant improvement by showing a cardioprotective effect histopathologically. Conclusion: THQ could be considered a crucial cardioprotective phytochemical against MTX cardiotoxicity