Peptide-mediated inactivation of recombinant and platelet plasminogen activator inhibitor-1 in vitro
| Autor: | David Ginsburg, Joseph D. Shore, William P. Fay, Steven T. Olson, Daniel T. Eitzman, Ann Marie Francis-Chmura, Daniel A. Lawrence |
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| Předmět: |
Blood Platelets
Time Factors medicine.medical_treatment Molecular Sequence Data Peptide chemistry.chemical_compound In vivo Fibrinolysis Plasminogen Activator Inhibitor 1 medicine Humans Amino Acid Sequence Peptide sequence Reactive center Blood Coagulation chemistry.chemical_classification Binding Sites biology General Medicine Molecular biology Peptide Fragments Recombinant Proteins Kinetics chemistry Plasminogen activator inhibitor-1 biology.protein Vitronectin Plasminogen activator Research Article Protein Binding |
| Zdroj: | Scopus-Elsevier |
| Popis: | Plasminogen activator inhibitor-1 (PAI-1), the primary inhibitor of tissue-type plasminogen activator (t-PA) and urokinase plasminogen activator, is an important regulator of the blood fibrinolytic system. Elevated plasma levels of PAI-1 are associated with thrombosis, and high levels of PAI-1 within platelet-rich clots contribute to their resistance to lysis by t-PA. Consequently, strategies aimed at inhibition of PAI-1 may prove clinically useful. This study was designed to test the hypothesis that a 14-amino acid peptide, corresponding to the PAI-1 reactive center loop (residues 333-346), can rapidly inhibit PAI-1 function. PAI-1 (0.7 microM) was incubated with peptide (55 microM) at 37 degrees C. At timed intervals, residual PAI-1 activity was determined by addition of reaction mixture samples to t-PA and chromogenic substrate. The T1/2 of PAI-1 activity in the presence of peptide was 4 +/- 3 min compared to a control T1/2 of 98 +/- 18 min. The peptide also inhibited complex formation between PAI-1 and t-PA as demonstrated by SDS-PAGE analysis. However, the capacity of the peptide to inhibit PAI-1 bound to vitronectin, a plasma protein that stabilizes PAI-1 activity, was markedly attenuated. Finally, the peptide significantly enhanced in vitro lysis of platelet-rich clots and platelet-poor clots containing recombinant PAI-1. These results indicate that a 14-amino acid peptide can rapidly inactivate PAI-1 and accelerate fibrinolysis in vitro. These studies also demonstrate that PAI-1 function can be directly attenuated in a physiologic setting and suggest a novel approach for augmenting fibrinolysis in vivo. |
| Databáze: | OpenAIRE |
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