Potential of nafimidone derivatives against co-morbidities of epilepsy: In vitro, in vivo, and in silico investigations

Nafimidone is known for its clinical antiepileptic effects and alcohol derivatives of nafimidone were reported be potent anticonvulsants. These compounds are structurally similar to miconazole, which is known to inhibit cholinesterases, protect neurons, and ameliorate cognitive decline. Herein, we aimed to reveal the potential of three nafimidone alcohol esters (5 g, 5i, and 5 k), which were previously reported for their anticonvulsant effects, against co-morbidities of epilepsy such as inflammatory and neuropathic pain, cognitive and behavioral deficits, and neuron death, and understand their roles in related pathways such as gamma-butyric acid type A (GABA(A)) receptor and cholinesterases using in vitro, in vivo and in silico methods. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used for cytotoxicity evaluation, hippocampal slice culture assay for neuroprotection, formalin test for acute and inflammatory pain, sciatic ligation for neuropathic pain, Morris water maze and open field locomotor tasks for cognitive and behavioral deficits, radioligand binding for GABA(A) receptor affinity, spectrophotometric methods for cholinesterase inhibition in vitro, and molecular docking in silico. The compounds were non-toxic to fibroblast cells. 5 k was neuroprotective against kainic acid-induced neuron death. 5i reduced pain response of mice in both the acute and the inflammatory phases. 5i improved survival upon status epilepticus. The compounds showed no affinity to GABA(A) receptor but inhibited acetylcholinesterase, 5 k also inhibited butyrylcholinesterase. The compounds were predicted to interact mainly with the peripheric anionic site of cholinesterase enzymes. The title compounds showed neuroprotective, analgesic, and cholinesterase inhibitory effects, thus they bear promise against certain co-morbidities of epilepsy with neurological insults.

Automated summary

This study investigated the potential of three nafimidone alcohol esters against comorbidities of epilepsy, such as inflammatory and neuropathic pain, cognitive and behavioral deficits, and neuron death. The compounds demonstrated neuroprotective, analgesic, and cholinesterase inhibitory effects.