Peroxynitrite--altered platelet mitochondria--a new link between inflammation and hemostasis.

Abstract

Using porcine blood, we tested the hypothesis that peroxynitrite (ONOO(-)) may affect platelet-fibrin clot formation, clot retraction rate (CRR) and fibrinolysis through the inhibition of platelet energy production. It was found that ONOO(-) reduces CRR and enlarges final clot size in platelet rich plasma (PRP) (IC(50)=100μM) and in whole blood (IC(50)=200μM) dose-dependently. In a reconstituted system (washed platelets+fibrinogen), CRR was inhibited by 5-100nM ONOO(-) (IC(50)=25nM). Concentrations of ONOO(-) reducing CRR in PRP, inhibited platelet oxygen consumption, augmented lactate production and decreased total ATP contents in clots derived from PRP. In washed platelets ONOO(-) (5-20nM) produced a drop of the mitochondrial transmembrane potential (ΔΨ(m)). Blocking of mitochondrial energy production resulted in a reduction of CRR, whereas inhibition of glycolysis failed to affect CRR. ONOO(-), up to 300μM, failed to affect coagulation in platelet free plasma. Fibrinolysis of platelet-fibrin clots was enhanced by ONOO(-) (25-300μM), cytochalasin B and following the reduction of platelet energy production. Fibrinolysis of plasma clots was resistant to ONOO(-) treatment up to a concentration of 500μM. Tromboelastometry (ROTEM) measurements performed in PRP show that inhibition of platelet energy production or treatment with ONOO(-) (100-300μM) diminishes MCF, alpha angle and MCE parameters. Blockage the platelet contractile apparatus by cytochalasin B resulted in reduction of CRR and ROTEM variables (MCF, alpha angle, MCE). We conclude that physiologically relevant ONOO(-) concentrations may inhibit clot retraction, reduce clot stability and accelerate its lysis through the inhibition of platelet mitochondrial energy production.

• Authors: Tomasz Misztal, Katarzyna Przesław, Tomasz Rusak, Marian Tomasiak
• Journal: Thrombosis research (Thromb Res) Vol. 131 Issue 1 Pg. e17-25 (Jan 2013) ISSN: 1879-2472 [Electronic] United States
• PMID: 23200902 (Publication Type: Journal Article)
• Copyright: Copyright © 2012 Elsevier Ltd. All rights reserved.

Chemical References

• Actins
• Platelet Aggregation Inhibitors
• Peroxynitrous Acid
• Lactic Acid
• Adenosine Triphosphate

Topics

• Actins (metabolism)
• Adenosine Triphosphate (blood)
• Animals
• Blood Platelets (drug effects, immunology, metabolism)
• Energy Metabolism (drug effects)
• Female
• Fibrinolysis (drug effects)
• Inflammation (blood, immunology)
• Kinetics
• Lactic Acid (blood)
• Male
• Membrane Potential, Mitochondrial
• Mitochondria (drug effects, immunology, metabolism)
• Oxygen Consumption
• Peroxynitrous Acid (blood)
• Platelet Aggregation Inhibitors (pharmacology)
• Polymerization
• Sus scrofa
• Thrombelastography