The role of nitric oxide in anticonvulsant effects of lycopene supplementation on pentylenetetrazole-induced epileptic seizures in rats

Abstract

Recent studies have shown that natural antioxidant compounds have positive effects on the nervous system. Lycopene, the red pigment in tomatoes, is one of the potent natural antioxidants, and is used as supplementation because of its well-known health benefits. However, its effect on epileptic seizures and underlying mechanisms are still unclear. In this study, it was aimed to investigate the effect of lycopene on pentylenetetrazole-induced epileptic seizures in rats and to elucidate the nitric oxide pathway in this effect. In this study, thirty male Wistar albino rats were used. Animals were divided into five groups (n = 6 for each group) as control, saline (1 mL/kg/day serum physiologic), positive control (2 mg/kg/day diazepam), and lycopene (5 and 10 mg/kg/day) for ten days. Pentylenetetrazole (45 mg/kg) was given to induce a seizure in the tenth day except for the control. Passive avoidance test was carried out to evaluate memory function. Inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and nitric oxide (NO) levels were measured in the cortex and hippocampal brain regions using the ELISA kits. Lycopene supplementation prolonged epileptic seizure onset times and reduced seizure stages. Besides, lycopene supplementation improved memory impairment after seizures. Moreover, lycopene significantly reduced the level of iNOS, nNOS, and NO in the brain. Lycopene supplementation significantly alleviated seizures and memory impairment. Its anticonvulsive effect could be associated with the nitric oxide pathway. Lycopene supplementation could be useful as a supportive therapeutic agent in epileptic patients.

Keywords: Epilepsy; Lycopene; Nitric oxide; Pentylenetetrazole; Rats.