Oxidative and nitrosative stress in kidney disease: a case for cyclosporine A

Area of Science:

• Vascular Biology
• Immunopharmacology
• Oxidative Stress

Background:

• Cyclosporine A (CsA) is linked to endothelial dysfunction and atherosclerosis.
• Vascular dysfunction mediators include nitric oxide deficiency, TGFb-1, endothelin-1, reactive oxygen species (ROS), reactive nitrogen species (RNS), and vasoconstrictor eicosanoids.

Purpose of the Study:

• To investigate the mechanisms of CsA-induced endothelial damage.
• To explore the role of peroxynitrite and tyrosine nitration in CsA-mediated vascular dysfunction.

Main Methods:

• Treatment of Bovine Aortic Endothelial Cells (BAEC) with CsA.
• Measurement of reactive oxygen and nitrogen species.
• Assessment of peroxynitrite formation and tyrosine nitration.
• Identification of nitrated proteins, including manganese superoxide dismutase (MnSOD).

Main Results:

• CsA treatment increased intracellular reactive oxygen and nitrogen intermediates in BAEC.
• This increase led to peroxynitrite formation, mediating tyrosine nitration.
• Superoxide anion was identified as the limiting factor for peroxynitrite generation.
• CsA treatment resulted in the nitration of specific proteins like MnSOD.

Conclusions:

• Peroxynitrite formation and subsequent tyrosine nitration are key mechanisms of CsA-induced endothelial damage.
• Increased superoxide anion generation contributes to peroxynitrite formation in CsA-treated cells.
• These findings suggest potential therapeutic targets for mitigating CsA-associated vascular complications.