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Visualization of Neutrophil Extracellular Traps in Mesenteric Venules After Mesenteric Ischemia-Reperfusion Injury via Intravital Microscopy
07:05

Visualization of Neutrophil Extracellular Traps in Mesenteric Venules After Mesenteric Ischemia-Reperfusion Injury via Intravital Microscopy

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Reperfusion activates metalloproteinases that contribute to neurovascular injury

Aigang Lu1, Joseph F Clark, Joseph P Broderick

  • 1Department of Neurology, University of Cincinnati, Cincinnati, OH 45267-0532, USA.lua@ucmail.uc.edu

Experimental Neurology
|January 12, 2008
PubMed

Insights

Reperfusion after stroke potentiates matrix metalloproteinase (MMP) activation, increasing neurovascular injury. Inhibiting MMPs before reperfusion significantly reduced this damage, highlighting MMPs as therapeutic targets.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Pathology

Background:

  • Matrix metalloproteinases (MMPs) play a role in tissue remodeling and injury.
  • Understanding the role of MMPs during the reperfusion phase of ischemic stroke is crucial for developing effective treatments.

Purpose of the Study:

  • To investigate the effect of reperfusion on matrix metalloproteinase (MMP) activation.
  • To determine the relationship between MMP activation during reperfusion and the extent of neurovascular injury.
  • To evaluate the therapeutic potential of MMP inhibitors in mitigating reperfusion-induced brain damage.

Main Methods:

  • Middle cerebral artery occlusion (MCAO) model in rats to induce ischemia.
  • In situ and gel zymography to assess MMP activation.
  • Immunohistochemistry (EBA, collagen IV) and Cresyl violet staining to evaluate neurovascular and cellular injury.
  • Administration of a broad-spectrum MMP inhibitor (AHA) prior to reperfusion.

Main Results:

  • Reperfusion significantly accelerated and potentiated the activation of MMP-9 and MMP-2 compared to permanent ischemia.
  • Reperfusion led to increased injury of cerebral endothelial cells, basal lamina, neurons, and glial cells.
  • Administration of AHA before reperfusion reduced MMP-9 activation and subsequent neurovascular injury in the ischemic cerebral cortex.

Conclusions:

  • Reperfusion exacerbates neurovascular injury following ischemic stroke, partly through enhanced MMP activation.
  • Targeting MMPs with inhibitors like AHA before reperfusion shows promise in protecting the brain from ischemic damage.

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