Thymoquinone Ameliorates Chemotherapy-induced Cognitive Impairment (Chemobrain) by Inhibiting Oxidative Stress, Inflammatory Response in the Brain of Rat

The aim of this study was to investigate the therapeutic efficacy of antioxidant thymoquinone (TQ) treatment on neuroinflammation against the negative effects of Doxorubicin (DOX) used in cancer treatment on learning and memory by behavioural and molecular mechanisms. Forty male Wistar rats were divided into four groups: Control, DOX, TQ and DOX+TQ. DOX and DOX+TQ groups were injected with 3 mg/kg (i.p.) DOX for 4 weeks. TQ and DOX+TQ groups received 10 mg/kg TQ by gavage. Learning, locomotor activity, oxidative stress and inflammatory levels were evaluated. In behavioural experiments data, a significant decrease was observed in DOX group compared to Control group, while a significant increase was observed in DOX+TQ group compared to DOX group. Compared to the control group, TOC, IL-1β, IL-6 and TNF-α levels increased, while TAC level decreased in the DOX group. With TQ treatment, a significant decrease was observed in TOC, IL-1β, IL-6 and TNF-α levels in the TQ and DOX+TQ groups compared to the DOX group, while significant increases were observed in TAC level. In our study, DOX toxicity increased oxidative stress and neuroinflammation and caused learning and memory loss, while TQ decreased oxidative stress and neuroinflammation and improved learning and memory disorders.