Anti-Psychotic Drug Induced Tardive Dyskinesia: A Role for the Anti-Apoptotic Molecule Curcumin

Abstract

<p>Anti-psychotic drug (APD) administration can induce movement disorders including tardive dyskinesia (TD), characterized by abnormal movements of the oro-facial region and occasionally the trunk and limbs. The most widely accepted model of TD is the APD-induced vacuous chewing movement (VCM). While the mechanism of induction of TD remains unclear, there are two prevailing hypothesis: oxidative stress and dopamine supersensitivity. Currently available APDs antagonize dopamine D2 receptors (D2R) which can result in excessive dopamine accumulation and oxidation which was demonstrated to induce striatal neurodegeneration and increased oxidative stress. The dopamine supersensitivity hypothesis proposes that APD treatment causes an up-regulation of high affinity D2Rs to compensate for D2R antagonism. Curcumin, a derivative of turmeric, has been demonstrated to affect dopamine levels and hold significant anti-apoptotic potential. Thus, the goal of this study was to investigate curcumin’s potential to prevent haloperidol-induced behavioural and biochemical abnormalities. Four groups of rats were treated daily: control; haloperidol (at 2mg/kg intra-peritoneally); curcumin (at 200mg/kg orally in jello) and curcumin plus haloperidol. VCMs, catalepsy and locomotor activity were assessed. Animals were sacrificed and tissues removed for qPCR, immunoblot, receptor binding, and UPLC assessments. At day14 there was a significant increase in VCMs and catalepsy following haloperidol treatment, which was prevented by curcumin treatment. However, curcumin did not alter locomotor activity. Curcumin was demonstrated to increase the expression of the anti-apoptotic molecule BclXL and to increase striatal D2Rs. These investigations support the potential of curcumin in the prevention of TD and provide insight into the complex pathophysiology of this disorder.</p>