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Hyperglycemia and reactive oxygen species mediate apoptosis in aortic endothelial cells through Janus kinase 2

Amany Tawfik1, Liming Jin, Amy K L Banes-Berceli

  • 1Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912, USA.

Vascular Pharmacology
|November 1, 2005
PubMed

Insights

Activation of Janus kinase 2 (JAK2) is crucial in mediating endothelial cell apoptosis caused by reactive oxygen species (ROS) and high glucose. Inhibiting JAK2 prevents cell death, highlighting its role in oxidative stress responses.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Reactive oxygen species (ROS) contribute to endothelial dysfunction and cell death.
  • The precise signaling pathways involved in ROS-mediated endothelial cell responses remain unclear.

Purpose of the Study:

  • To investigate the role of Janus kinase 2 (JAK2) activation in the aortic endothelial cell (EC) response to ROS.
  • To test the hypothesis that JAK2 activation mediates EC apoptosis induced by oxidative stress.

Main Methods:

  • Exposure of ECs to high glucose (HG) or hydrogen peroxide (H2O2) to induce oxidative stress.
  • Assessment of EC apoptosis, JAK2 tyrosine phosphorylation, and caspase-3/PARP cleavage.
  • Inhibition of JAK2 using AG-490 or a dominant-negative JAK2 mutant.

Main Results:

  • HG and H2O2 exposure led to decreased cell density, apoptosis, and JAK2 phosphorylation in ECs.
  • JAK2 inhibition by AG-490 or dominant-negative JAK2 prevented apoptosis.
  • Inhibitors of Jun kinase, MAP kinase, Src kinase, and PI-3 kinase had no significant effect on apoptosis.

Conclusions:

  • JAK2 activation is a key mediator of EC apoptosis induced by oxidative stress (HG and H2O2).
  • Targeting JAK2 may offer a therapeutic strategy for conditions involving endothelial cell damage due to oxidative stress.

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