Glibenclamide ameliorates cerebral edema and improves outcomes in a rat model of status epilepticus

Neuropharmacology. 2017 Jul 15:121:1-11. doi: 10.1016/j.neuropharm.2017.04.016. Epub 2017 Apr 13.

Abstract

Glibenclamide (GBC), a sulfonylurea receptor 1 blocker, emerges recently as a promising neuron protectant in various neurological disorders. This study aimed to determine whether GBC improves survival and neurological outcome of status epilepticus (SE). Male Sprague-Dawley rats successfully undergoing SE for 2.5 h (n = 134) were randomly assigned to GBC or vehicle group. Rats in the GBC group received a loading dose of 10 μg/kg of GBC, followed by 1.2 μg/6 h for 3 days, while same dose of vehicle was used as control. The 28-day survival rate in the GBC group (11/23) was significantly higher than that in the vehicle group (8/36). In addition, the frequency and duration of spontaneous recurrent seizures in SE rats were profoundly reduced by GBC but not by vehicle treatment. Moreover, cognitive impairment was observed in the SE rats at day 28, which was reversed by GBC treatment. Meanwhile, cerebral edema, as well as neuronal loss, was decreased in several brain areas in the GBC group. Additionally, on the molecular basis, the subunits of sulfonylurea receptor 1/transient receptor potential M4 (SUR1-TRPM4) heterodimer were both strongly upregulated after SE but partly suppressed by GBC treatment. Furthermore, gene knockdown of Trpm4 in SE rats reduced BBB disruption and neuronal loss, similar to the inhibitory effects with GBC treatment. Taken together, GBC treatment markedly improved survival and neurologic outcomes after SE. The salutary effects of GBC were correlated to the alleviation of cerebral edema and reduction in neurological injury via down-regulation of SUR1-TRPM4 channel.

Keywords: Cerebral edema; Glibenclamide; Pilocarpine; Status epilepticus; Sulfonylurea receptor 1-transient receptor potential M4 channel.

MeSH terms

  • Animals
  • Blood-Brain Barrier / drug effects
  • Brain / drug effects
  • Brain / metabolism
  • Brain Edema / drug therapy*
  • Brain Edema / etiology*
  • Cognition Disorders / drug therapy
  • Cognition Disorders / etiology
  • Disease Models, Animal
  • Gene Expression Regulation / drug effects
  • Glyburide / therapeutic use*
  • Hypoglycemic Agents / therapeutic use*
  • Male
  • Maze Learning / drug effects
  • Muscarinic Agonists / toxicity
  • Phosphopyruvate Hydratase / metabolism
  • Pilocarpine / toxicity
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Spatial Learning / drug effects
  • Status Epilepticus / chemically induced
  • Status Epilepticus / complications*
  • Sulfonylurea Receptors / metabolism
  • TRPM Cation Channels / genetics
  • TRPM Cation Channels / metabolism

Substances

  • Abcc8 protein, rat
  • Hypoglycemic Agents
  • Muscarinic Agonists
  • RNA, Small Interfering
  • Sulfonylurea Receptors
  • TRPM Cation Channels
  • TRPM4 protein, rat
  • Pilocarpine
  • Phosphopyruvate Hydratase
  • Glyburide