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Inducible nitric oxide synthase mediates hippocampal caspase-3 activation in pneumococcal meningitis

Johann Braun1

  • 1Department of Neurology, Charite University Medicine, Berlin, Germany. johann.braun@charite.de

The International Journal of Neuroscience
|February 21, 2009
PubMed

Insights

Nitric oxide (NO), produced by inducible nitric oxide synthase (iNOS), contributes to brain damage in bacterial meningitis. Inactivating iNOS significantly reduced neuronal damage in mice with pneumococcal meningitis.

Area of Science:

  • Neuroscience
  • Immunology
  • Infectious Diseases

Background:

  • Bacterial meningitis, particularly pneumococcal meningitis, causes significant neuronal damage.
  • The role of nitric oxide (NO) in meningitis-induced brain injury remains unclear.

Purpose of the Study:

  • To investigate the role of inducible nitric oxide synthase (iNOS) in neuronal damage during experimental pneumococcal meningitis.

Main Methods:

  • Utilized a murine model of pneumococcal meningitis.
  • Compared neuronal damage in wild-type mice versus iNOS knockout mice.

Main Results:

  • Genetic inactivation of iNOS markedly reduced caspase-3-mediated neuronal damage in the hippocampus.
  • Protection in iNOS knockout mice was not due to altered bacterial growth, but host inflammatory mediators.

Conclusions:

  • NO produced by iNOS plays a crucial role in hippocampal caspase-3 activation and neuronal damage during pneumococcal meningitis.
  • Targeting iNOS may offer a therapeutic strategy to mitigate brain injury in bacterial meningitis.

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