Poly(ADP-ribose) polymerase-1 protects from oxidative stress induced endothelial dysfunction

Area of Science:

• Vascular Biology
• Oxidative Stress Research
• Enzymology

Background:

• Reactive oxygen species (ROS) are central to vascular disease pathogenesis.
• Poly (ADP-ribose) polymerase-1 (PARP-1), a nuclear enzyme, is activated by oxidative stress.

Purpose of the Study:

• To investigate the role of PARP-1 in protecting against acute intracellular oxidative stress-induced endothelial dysfunction.
• To elucidate the mechanisms by which PARP-1 influences vascular responses to oxidative insults.

Main Methods:

• Utilized PARP-1 knockout (PARP-1(-/-)) and wild-type (PARP-1(+/+)) mice subjected to paraquat (PQ) administration to induce oxidative stress.
• Assessed vascular function by measuring isometric tension in isolated aortic rings.
• Evaluated endothelium-dependent and independent relaxations, and the effects of antioxidants and enzyme inhibitors.

Main Results:

• Paraquat significantly impaired endothelium-dependent relaxations to acetylcholine in PARP-1(-/-) mice but not in PARP-1(+/+) mice.
• Endothelium-independent relaxations to sodium nitroprusside were unaffected by paraquat in either genotype.
• Antioxidants (PEG-superoxide dismutase and PEG-catalase) and indomethacin ameliorated the PQ-induced endothelial dysfunction in PARP-1(-/-) mice, suggesting a role for ROS and prostanoids.

Conclusions:

• PARP-1 plays a protective role against acute intracellular oxidative stress-induced endothelial dysfunction.
• The protective effect of PARP-1 involves the inhibition of ROS-induced production of vasoconstrictor prostanoids.
• Targeting PARP-1 or related pathways may offer therapeutic potential for vascular diseases associated with oxidative stress.