NEUROMODULATORY EFFECTS OF THYMOQUINONE IN EXTENUATING OXIDATIVE STRESS IN CHLORPROMAZINE TREATED RATS.

The present study was undertaken to evaluate the possible protective effect of thymoquinone on chlorpromazine induced catalepsy, locomotor activity and cerebral oxidative stress in rats. The rats were divided into four groups, each group containing eight animals. The animals were evaluated after repeated administration of chlorpromazine (CPZ) 30 min before the administration of thymoquinone (TQ) for 21 days. Catalepsy was assessed using block method whereas the locomotor activity was assessed using acceleratory rotarod and actophotometer. Markers of oxidative stress parameters (LPO, GSH, GPx, GR, GST and CAT) were evaluated in the brain of rats. The cataleptic scores were significantly increased in CPZ treated rats when compared with normal control rats. Oral administration of TQ (5 and 10 mg/kg) significantly decreased cataleptic scores when compared with chlorpromazine (CPZ) treated rats. The muscle coordination and spontaneous locomotor activity was significantly decreased in CPZ treated rats when compared with normal control rats. Treatment with TQ significantly improved the muscle coordination and spontaneous locomotor activity when compared with CPZ treated rats. TQ treated rats significantly reduced the elevated levels of lipid peroxidation (LPO), increased levels of antioxidant enzymes i.e., reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and catalase (CAT) when compared with CPZ treated rats. The results clearly suggest that supplementation with TQ can be used to preclude CPZ induced extrapyramidal side effects and may find a role in reducing the oxidative stress.