Comorbidity between epilepsy and depression: role of hippocampal interleukin-1beta

Neurobiol Dis. 2010 Feb;37(2):461-7. doi: 10.1016/j.nbd.2009.11.001. Epub 2009 Nov 10.

Abstract

Depression is a frequent comorbidity of temporal lobe epilepsy (TLE); however, its mechanisms remain poorly understood and effective therapies are lacking. Augmentation of hippocampal interleukin-1beta (IL-1beta) signaling may be a mechanistic factor of both TLE and clinical depression. We examined whether pharmacological blockade of hippocampal interleukin-1 receptor exerts antidepressant effects in an animal model of comorbidity between TLE and depression, which developed in Wistar rats following pilocarpine status epilepticus (SE). In post-SE animals, depression-like state was characterized by behavioral equivalents of anhedonia and despair; dysregulation of the hypothalamo-pituitary-adrenocortical axis; compromised raphe-hippocampal serotonergic transmission. Two-week long bilateral intrahippocampal infusion of human recombinant Interleukin-1 receptor antagonist (IL-1ra) improved all of the examined depressive impairments, without modifying spontaneous seizure frequency and without affecting normal parameters in naïve rats. These findings implicate hippocampal IL-1beta in epilepsy-associated depression and provide a rationale for the introduction of IL-1beta blockers in the treatment of depression in TLE.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antidepressive Agents / pharmacology
  • Behavior, Animal / drug effects
  • Behavior, Animal / physiology
  • Comorbidity
  • Convulsants / pharmacology
  • Depressive Disorder / drug therapy
  • Depressive Disorder / immunology
  • Depressive Disorder / physiopathology*
  • Disease Models, Animal
  • Epilepsy / complications*
  • Epilepsy / immunology
  • Epilepsy / physiopathology*
  • Hippocampus / immunology
  • Hippocampus / metabolism*
  • Hippocampus / physiopathology*
  • Hypothalamo-Hypophyseal System / physiopathology
  • Interleukin 1 Receptor Antagonist Protein / pharmacology
  • Interleukin-1beta / antagonists & inhibitors
  • Interleukin-1beta / metabolism*
  • Male
  • Neural Pathways / physiopathology
  • Pilocarpine / pharmacology
  • Pituitary-Adrenal System / physiopathology
  • Raphe Nuclei / physiopathology
  • Rats
  • Rats, Wistar
  • Receptors, Interleukin-1 / antagonists & inhibitors
  • Receptors, Interleukin-1 / metabolism
  • Status Epilepticus / chemically induced
  • Status Epilepticus / complications
  • Status Epilepticus / physiopathology

Substances

  • Antidepressive Agents
  • Convulsants
  • Interleukin 1 Receptor Antagonist Protein
  • Interleukin-1beta
  • Receptors, Interleukin-1
  • Pilocarpine