Neuroprotective effects of Aframomum melegueta on lithium–pilocarpine-induced prefrontal cortical damage in Wistar rats

Epileptic seizures are linked to significant neurochemical, oxidative, inflammatory, and structural changes in the brain, especially within the prefrontal cortex, a region essential for cognition and behaviour. Oxidative stress and neuroinflammation are essential factors in seizure-induced neurodegeneration. Aframomum melegueta, a medicinal plant abundant in bioactive phytochemicals, has exhibited antioxidant and neuroprotective activities; nevertheless, its impact on prefrontal cortical damage subsequent to epilepsy is little defined. This study assessed the impact of Aframomum melegueta on behavioural, biochemical, neurochemical, histological, and inflammatory alterations in the prefrontal cortex of Wistar rats with epilepsy caused by lithium chloride and pilocarpine.

Twenty-four male Wistar rats were randomly allocated into four groups: control, lithium-pilocarpine (LP), LP treated with Aframomum melegueta (400 mg/kg), and LP treated with carbamazepine (100 mg/kg). Seizures were elicited with the administration of lithium chloride, succeeded by pilocarpine. Behavioural evaluations were performed via the open field and Y-maze assessments. Prefrontal cortical tissues were examined for neurotransmitters (GABA and glutamate), oxidative stress indicators (malondialdehyde and superoxide dismutase), and the inflammatory cytokine (IL-6). Histological and immunohistochemical assessments were conducted utilising haematoxylin and eosin, Cresyl fast violet, Luxol fast blue, and GFAP staining techniques.

Lithium-pilocarpine induction resulted in considerable behavioural abnormalities, an imbalance of excitatory and inhibitory neurotransmitters, heightened lipid peroxidation, diminished antioxidant activity, raised IL-6 levels, and pronounced neuronal degeneration, demyelination, and astrogliosis in the prefrontal cortex. Treatment with Aframomum melegueta markedly improved behavioural deficits, decreased glutamate and IL-6 concentrations, bolstered antioxidant defences, maintained neuronal and myelin integrity, and mitigated astrocytic activation, exhibiting results akin to carbamazepine.

Aframomum melegueta demonstrates considerable neuroprotective properties against lithium-pilocarpine-induced damage in the prefrontal cortex, presumably via antioxidant, anti-inflammatory, and neuromodulatory pathways. The results endorse its potential as an adjunctive treatment agent in the management of epilepsy.