Immunomodulatory effect of Celecoxib on HMGB1/TLR4 pathway in a recurrent seizures model in immature rats

Pharmacol Biochem Behav. 2018 Jul:170:79-86. doi: 10.1016/j.pbb.2018.05.007. Epub 2018 May 26.

Abstract

Epileptic seizures constitute an important problem in pediatric neurology during the developmental period. The frequency and nosological significance of seizures, as well as their association with epileptogenesis, may be related to underlying mechanisms such as neuroinflammation. Those mechanisms of response activate inflammatory molecules induced in the neurons, activated glial cells and endothelial cells via the key HMGB1/TLR4 pathway. In this study, the drug celecoxib (CCX) was used as a blocker of the cyclooxygenase 2 (COX-2) and HMGB1/TLR-4 pathways. The experimental model was implemented in 10-day-old neonatal Sprague Dawley rats to induce recurrent seizures with kainic acid (KA, 1.4 mg/kg). Data were evaluated at early (14 PND) and late (30 PND) time points. The results showed that the CCX and CCX + pentobarbital (PB) groups exhibited a protective effect by significantly increasing the time latency of seizures compared to the KA group at both early (p < 0.01) and late (p < 0.001) times. When the CCX group was compared to the KA group, there was also a significant decrease in the number of HMGB1 and TLR-4 transcripts (p < 0.05) and in COX-2 protein expression (p < 0.05) in the most important areas for seizure generation (the hippocampus and cortex) at both the early and late time points. These results demonstrated that CCX treatment after epileptic seizures has a neuroprotective effect due to the inhibition of proinflammatory proteins and associated signaling pathways and reduces seizure susceptibility. Additionally, the timely intervention of inflammatory pathways will reduce the risk of developing epilepsy in adulthood.

Keywords: Celecoxib; Early seizures; HMGB1; Inflammation; Kainic acid; TLRs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Celecoxib / pharmacology*
  • Cyclooxygenase 2 / genetics
  • Female
  • HMGB1 Protein / genetics
  • HMGB1 Protein / physiology*
  • Hippocampus / metabolism
  • Immunologic Factors / pharmacology*
  • Kainic Acid / pharmacology
  • Neuroprotective Agents / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time
  • Recurrence
  • Seizures / drug therapy*
  • Seizures / immunology
  • Signal Transduction / drug effects*
  • Toll-Like Receptor 4 / genetics
  • Toll-Like Receptor 4 / physiology*

Substances

  • HMGB1 Protein
  • Hbp1 protein, rat
  • Immunologic Factors
  • Neuroprotective Agents
  • Tlr4 protein, rat
  • Toll-Like Receptor 4
  • Cyclooxygenase 2
  • Celecoxib
  • Kainic Acid