Psychopharmacological evaluation of antidepressant‐like activity of ethanol seed extract of grains of paradise (Aframomum melegueta K. Schum.) in mice

The antidepressant‐like activity of ethanol seed extract of Aframomum melegueta (AM) in mice was evaluated in this study. The duration of immobility was measured 30 min after oral administration of AM (25–400 mg/kg) in forced swim test. In the unpredictable chronic mild stress (UCMS) paradigm, mice were treated with AM (25–100 mg/kg) 30 min before exposure to different stressors for 14 days. Thereafter, sucrose preference test, tail suspension test, and test for anxiety were done. The brain concentrations of malondialdehyde and glutathione were estimated spectrophotometrically. Brain histology and population of healthy neurons in cornu ammonis 3 of the hippocampus were also assessed. AM (25 and 50 mg/kg) significantly decreased the duration of immobility in forced swim test and prevented UCMS‐induced anhedonia and anxiety‐like behaviors, suggesting antidepressant potentials. The extract decreased malondialdehyde and increased glutathione concentrations in UCMS‐induced mice. Therefore, AM extract offers protection against UCMS‐induced damage to cornu ammonis 3 hippocampal neuronal cells indicating neuroprotection. Practical applications The seed of Grains of Paradise (Aframomum melegueta) is used in traditional medicine for fatigue and impotence, which are prominent symptoms of major depression. It is also widely chewed for its presumed central nervous system stimulant and endurance promoting effects. The results of this study revealed valuable evidence concerning the possible use of Grains of Paradise as an affordable natural, alternative, and/or complementary therapy with antioxidative and neuroprotective potentials. Consumption of these seeds in the right quantity might provide health benefits as Grains of Paradise exhibited antidepressant‐like effect via inhibition of oxidative stress and neuroprotection.