Raloxifene potentiates the effect of fluoxetine against maximal electroshock induced seizures in mice

Eur J Pharm Sci. 2020 Apr 15:146:105261. doi: 10.1016/j.ejps.2020.105261. Epub 2020 Feb 13.

Abstract

The evidence to guide clinicians regarding rationale polytherapy with current antiepileptic drugs (AEDs) is lacking, and current practice recommendations are largely empirical. The excessive drug loading with combinatorial therapies of existing AEDs are associated with escalated neurotoxicity, and that emergence of pharmacoresistant seizures couldn't be averted. In pursuit of judicious selection of novel AEDs in combinatorial therapies with mechanism based evidences, standardized dose of raloxifene, fluoxetine, bromocriptine and their low dose combinations, were experimentally tested for their impact on maximal electroshock (MES) induced tonic hind limb extension (THLE) in mice. Hippocampal neuropeptide Y (NPY) levels, oxidative stress and histopathological studies were undertaken. The results suggest the potentiating effect of 4 mg/kg raloxifene on 14 mg/kg fluoxetine against MES induced THLE, as otherwise monotherapy with 4 mg/kg raloxifene was unable to produce an effect. The results also depicted better efficacy than carbamazepine (20 mg/kg), standard AED. Most profoundly, MES-induced significant (P < 0.001) reduction in hippocampal NPY levels, that were escalated insignificantly with the duo-drug combination, suggesting some other mechanism in mitigation of electroshock induced seizures. These results were later corroborated with assays to assess oxidative stress and neuronal damage. In conclusion, the results demonstrated the propitious therapeutic benefit of duo-drug low dose combination of drugs; raloxifene and fluoxetine, with diverse mode of actions fetching greater effectiveness in the management of generalized tonic clonic seizures (GTCS).

Keywords: Dopamine; Epilepsy; Generalized tonic clonic seizures; Neurodegeneration; Neurological disorders; Neuropeptide Y; Seizures; Serotonin.

MeSH terms

  • Animals
  • Anticonvulsants / therapeutic use*
  • Bromocriptine / administration & dosage
  • Bromocriptine / pharmacology
  • Bromocriptine / therapeutic use
  • Disease Models, Animal
  • Drug Synergism
  • Drug Therapy, Combination
  • Electroshock / adverse effects*
  • Fluoxetine / administration & dosage
  • Fluoxetine / pharmacology
  • Fluoxetine / therapeutic use*
  • Glutamic Acid / metabolism
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Mice
  • Neuropeptide Y / metabolism
  • Oxidative Stress / drug effects
  • Raloxifene Hydrochloride / administration & dosage
  • Raloxifene Hydrochloride / pharmacology
  • Raloxifene Hydrochloride / therapeutic use*
  • Receptors, Dopamine / metabolism
  • Receptors, Serotonin / metabolism
  • Seizures / etiology
  • Seizures / prevention & control*
  • Signal Transduction / drug effects

Substances

  • Anticonvulsants
  • Neuropeptide Y
  • Receptors, Dopamine
  • Receptors, Serotonin
  • Fluoxetine
  • Bromocriptine
  • Glutamic Acid
  • Raloxifene Hydrochloride