Ameliorative effect of allopurinol on cisplatin-induced memory impairment in male Wistar rat

Neurotoxicity is an adverse effect of chemotherapy drugs on the central nervous system. Many studies havedemonstrated that xanthine oxidase inhibitors prevent the formation of reactive oxygen species (ROS). The presentstudy aimed to investigate the effects of allopurinol as an oxidase inhibitor on the learning and memory impairmentinduced by cisplatin. This study was conducted on 40 male Wistar rats, which were randomly divided into fivegroups, as follows: 1) control injected with saline (1 ml/kg/i.p); 2) cisplatin (5 mg/kg/once a week; i.p.); 3) allopurinol(ALP; 50 mg/kg/once a week; P.O.); 4) Cis+ALP 50 (cisplatin 5 mg/kg/i.p and allopurinol50 mg/kg/once a week;P.O.) and 5) Cis+ALP 100 (cisplatin 5 mg/kg/i.p and allopurinol100 mg/kg/once a week; P.O.). Drugs wereadministered for five weeks in all groups. The interval between administrations of drugs were half an hour. Morriswater maze (MWM) was used to evaluate the memory and learning of the animals. The tissue brain concentrationsof malondialdehyde (MDA), thiol, and superoxide dismutase (SOD) were measured using biochemical tests.According to the results, the cisplatin group had longer escape latency and shorter time spent and traveled pathwayin the target quadrant compared to the control group. On the other hand, allopurinol treatment significantly reversedthe results of the spatial memory test. The biochemical data indicated that cisplatin increased MDA concentrationbut decreased thiol and SOD activity compared to the control group. Administration of allopurinol decreased theMDA level but increased the thiol levels in the cortex and hippocampus tissues. Therefore, it was concluded thatallopurinol could improve cisplatin-induced memory impairment by affecting the oxidative status of the brain tissue.