Effect of orlistat on lipid peroxidation, Na+, K+ ATPase, glutathione and serotonin in rat brain.

The aim of this study was to evaluate the effect of orlistat, a drug used in weight loss, on 5-HT and indicators of oxidative stress in rat brain. Orlistat, 12 mg/kg was administered to Wistar rats as single dose or successive doses on 3 consecutive days. Blood glucose and oxidative stress indicators were detected by measurement of lipid peroxidation, Na+, K+ ATPase, glutathione and serotonin levels using previous validated methods. The levels of glucose decreased in rats receiving successive doses. The activity of Na+, K+ ATPase and total ATPase was reduced in rats receiving successive doses, while the level of lipid peroxidation increased slightly in both groups. Glutathione underwent significant reduction in the successive doses group (p < 0.05). 5-HT increased significantly after single dose treatment (p < 0.05). Orlistat can induce pro-oxidant effects in the brain due to alteration of serotonergic metabolism and the reduction of glutathione.