Volume 2 Supplement 1

Abstracts of the 51st Workshop for Pediatric Research

Open Access

Neuroprotection after infection-sensitized neonatal hypoxic-ischemic brain injury

  • Hemmen Sabir1,
  • Damjan Osredkar2,
  • Elke Maes2,
  • Thomas Wood2 and
  • Marianne Thoresen2
Molecular and Cellular Pediatrics20152(Suppl 1):A11

DOI: 10.1186/2194-7791-2-S1-A11

Published: 1 July 2015

Background

Therapeutic hypothermia (HT) is standard treatment after perinatal hypoxic-ischemic (HI) injury. However, around 50% of asphyxiated newborns still suffer poor outcome, some of which may have been exposed to perinatal infection prior to HI, as infection may increase vulnerability to HI injury.

Aims

To develop an infection-sensitized newborn animal model of HI injury and to investigate whether HT is neuroprotective in this setting.

Methods

Seven day old rat pups were injected either with vehicle (NaCl 0.9%) or E.coli lipopolysaccharide (LPS). Subsequently, they were exposed to left carotid ligation followed by global hypoxia inducing a unilateral HI injury. Pups were randomized to the following treatments: 1) Vehicle treated HI-pups receiving normothermia treatment (NT) (Veh-NT); 2) LPS treated HI-pups receiving NT treatment (LPS-NT); 3) vehicle treated HI-pups receiving HT treatment (Veh-HT); or 4) LPS treated HI-pups receiving HT treatment (LPS-HT). Relative area loss of the left/right hemisphere and the areas of hippocampi were measured after one-week survival.

Results

Mean brain area loss in the Veh-NT group was 11.2%±14%. The brain area loss in LPS-NT pups was 29.8%±17%, being significantly higher than in the Veh-NT group (p = 0.002). The Veh-HT group had a significantly smaller brain area loss (5.4%±6%) when compared to Veh-NT group (p = 0.043). The LPS-HT group showed a brain area loss of 32.5%±16%, being significantly higher than in the Veh-HT group (p < 0.001). LPS-HT group also had significantly smaller size of the left hippocampus. LPS-sensitization significantly decreased the sizes of the right, unligated-hemispheres, independent of post-HI treatment.

Conclusions

Therapeutic hypothermia is not neuroprotective in this infection-sensitized HI brain injury model. Lack of neuroprotection was particularly seen in the hippocampus. The exact mechanisms remain unclear and further investigation is needed to explain why a neuroprotective therapy loses its efficacy and how hypothermia may be optimized.

Authors’ Affiliations

(1)
Department of General Pediatrics, Neonatology and Pediatric Cardiology, Children's Hospital, Heinrich-Heine University Düsseldorf
(2)
Department of Physiology, Institute of Basic Medical Sciences, University of Oslo

Copyright

© Sabir et al. 2015

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.