Characterization of the anticonvulsant effect of dapsone on metabolic activity assessed by [18F]FDG -PET after kainic acid-induced status epilepticus in rats

Brain Res. 2023 Mar 15:1803:148227. doi: 10.1016/j.brainres.2022.148227. Epub 2022 Dec 30.

Abstract

Background: Development of effective drugs for epilepsy are needed, as nearly 30 % of epileptic patients, are resistant to current treatments. This study is aimed to characterize the anticonvulsant effect of dapsone (DDS), in the kainic acid (KA)-induced Status Epilepticus (SE) by recording the brain metabolic activity with an [18F]FDG-PET analysis.

Methods: Wistar rats received KA (10 mg/kg, i.p., single dose) to produce sustained seizures. [18F]FDG-PET and electroencephalographic (EEG) studies were then performed. DDS or vehicle were administered 30 min before KA. [18F]FDG uptake and EEG were evaluated at baseline, 2 and 25 h after KA injection. Likewise, caspase-8, 3 hippocampal activities and Fluoro-Jade B neuronal degeneration and Hematoxylin-eosin staining were measured 25 h after KA.

Results: PET data evaluated at 2 h showed hyper-uptake of [18F]FDG in the control group, which was decreased by DDS. At 25 h, hypo-uptake was observed in the control group and higher values due to DDS effect. EEG spectral power was increased 2 h after KA administration in the control group during the generalized tonic-clonic seizures, which was reversed by DDS, correlated with [18F]FDG-PET uptake changes. The values of caspases-8 activity decreased 48 and 43 % vs control group in the groups treated with DDS (12.5 y 25 mg/kg respectively), likewise; caspase-3 activity diminished by 57 and 53 %. Fewer degenerated neurons were observed due to DDS treatments.

Conclusions: This study pinpoints the anticonvulsant therapeutic potential of DDS. Given its safety and effectiveness, DDS may be a viable alternative for patients with drug-resistant epilepsy.

Keywords: Caspases 8 and 3; Dapsone; EEG; Fluoro-Jade B; Status epilepticus; [(18)F]FDG (-)PET.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anticonvulsants / pharmacology
  • Anticonvulsants / therapeutic use
  • Dapsone / pharmacology
  • Epilepsy* / metabolism
  • Fluorodeoxyglucose F18 / metabolism
  • Hippocampus / metabolism
  • Kainic Acid / pharmacology
  • Rats
  • Rats, Wistar
  • Seizures / metabolism
  • Status Epilepticus* / chemically induced
  • Status Epilepticus* / diagnostic imaging
  • Status Epilepticus* / drug therapy

Substances

  • Anticonvulsants
  • Kainic Acid
  • Fluorodeoxyglucose F18
  • Dapsone