Neonatal Escherichia coli K1 meningitis causes learning and memory impairments in adulthood

J Neuroimmunol. 2014 Jul 15;272(1-2):35-41. doi: 10.1016/j.jneuroim.2014.05.003. Epub 2014 May 10.

Abstract

Neonatal Escherichia coli meningitis continues to be an important cause of mortality and morbidity in newborns worldwide. The aim of this study was to investigate the cytokines/chemokines, brain-derived neurotrophic factor (BDNF) levels, blood-brain barrier integrity in neonatal rats following E. coli K1 experimental meningitis infection and subsequent behavioural parameters in adulthood. In the hippocampus, interleukin increased at 96 h, IL-6 at 12, 48 and 96 h, IL-10 at 96 h, cytokine-induced neutrophil chemoattractant-1 at 6, 12, 24, 48 and 96 h, and BDNF at 48 and 96 h. In the cerebrospinal fluid, tumour necrosis factor alpha levels increased at 6, 12, 24, 48 and 96 h. The BBB breakdown occurred at 12 h in the hippocampus, and at 6h in the cortex. We evaluated behavioural parameters in adulthood: habituation to the open-field, step-down inhibitory avoidance, object recognition, continuous multiple-trials step-down inhibitory avoidance and forced swimming tasks. In adulthood, the animals showed habituation and aversive memory impairment. The animals needed a significant increase in the number of training periods to learn and not had depressive-like symptoms.

Keywords: Chemokines; Cytokines; Escherichia coli; Memory; Neonatal meningitis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology
  • Blood-Brain Barrier / physiopathology
  • Brain-Derived Neurotrophic Factor / metabolism
  • Ceftriaxone / pharmacology
  • Ceftriaxone / therapeutic use
  • Cytokines / metabolism
  • Disease Models, Animal
  • Escherichia coli Infections / complications*
  • Escherichia coli Infections / drug therapy
  • Gene Expression Regulation, Bacterial / drug effects
  • Gene Expression Regulation, Bacterial / physiology*
  • Learning Disabilities / etiology*
  • Male
  • Memory Disorders / etiology*
  • Meningitis, Bacterial* / complications
  • Meningitis, Bacterial* / etiology
  • Meningitis, Bacterial* / microbiology
  • Rats
  • Rats, Wistar
  • Reaction Time / drug effects
  • Recognition, Psychology / drug effects
  • Recognition, Psychology / physiology
  • Time Factors

Substances

  • Anti-Bacterial Agents
  • Brain-Derived Neurotrophic Factor
  • Cytokines
  • Ceftriaxone