B vitamins attenuate haloperidol-induced orofacial dyskinesia in rats: possible involvement of antioxidant mechanisms.

Tardive dyskinesia (TD) is a serious motor disorder related to antipsychotic therapy, whose pathophysiology is associated to oxidative stress. Treatments that maintain antipsychotic efficacy while reducing TD risk are awaited. Haloperidol (HAL), a typical antipsychotic, is used as a putative murine model of TD. Here, we evaluated the protective role of vitamins B1, B6, and B12 alone or in combination (vitamin B cocktail) in preventing the HAL-induced orofacial dyskinesia (OD), based on their antioxidant properties. HAL (1 mg/kg) administered intraperitoneally to Wistar rats for 21 days caused OD and increased catalepsy time. The daily administration of B vitamins (B1 : B6 : B12 at 60 : 60 : 0.6 mg/kg) alone or the vitamin B cocktail, along with HAL, prevented the development of OD. Catalepsy time reduced in all groups treated with B vitamins, but to a lesser extent than OD. The participation of oxidative stress was assessed by the determination of reduced glutathione (GSH) levels and lipid peroxide formation in the striatum. HAL significantly decreased GSH levels and enhanced lipid peroxidation, whereas B1, B12, and vitamin B cocktail prevented the decrease in GSH levels. All groups treated with B vitamins presented a decrease in lipid peroxide formation. The data suggest a promising role for B vitamins in the prevention of OD.