Fibrinolysis in a lipid environment: modulation through release of free fatty acids
| Autor: | Raymund Machovich, Balázs Váradi, Colin Longstaff, Péter Sótonyi, F. Timár, Gyöngyi Rábai, V. Kristóf, Krasimir Kolev |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Proteases
Plasmin medicine.medical_treatment Reteplase Fatty Acids Nonesterified In Vitro Techniques 030204 cardiovascular system & hematology Fatty Acid-Binding Proteins Fibrin Fatty acid-binding protein 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Fibrinolysis medicine Animals Humans tissue-type plasminogen activator plasmin Fluorescent Dyes 030304 developmental biology 0303 health sciences biology reteplase Plasminogen Thrombosis Hematology Lipid Metabolism Recombinant Proteins Kinetics Oleic acid oleic acid Biochemistry chemistry biology.protein Cattle Plasminogen activator medicine.drug |
| Zdroj: | Journal of Thrombosis and Haemostasis |
| ISSN: | 1538-7836 |
| Popis: | Summary. Background: Thrombolysis is conventionally regarded as dissolution of the fibrin matrix of thrombi by plasmin, but the structure of clots in vivo includes additional constituents (proteins, phospholipids) that modulate their solubilization. Objective: We examined the presence of free fatty acids in thrombi and their effects on distinct stages of fibrinolysis (plasminogen activation, plasmin activity). Methods and Results: Using the fluorescent probe acrylodated intestinal fatty acid-binding protein, variable quantities (up to millimolar concentrations) of free fatty acids were demonstrated in surgically removed human thrombi. Oleic acid at relevant concentrations reversibly inhibits more than 90% of the amidolytic activity of plasmin on a synthetic substrate (Spectrozyme PL), but only partially inhibits its fibrinolytic activity measured using turbidimetry. Chromogenic assays detecting the generated plasmin activity show that plasminogen activation by tissue-type plasminogen activator (t-PA) is completely blocked by oleic acid in the fluid phase, but is accelerated on a fibrin matrix. A recombinant derivative of t-PA (reteplase) develops higher fibrin specificity in the presence of oleic acid, because both the inhibition of plasminogen activation in free solution and its enhancement on fibrin template are stronger than with wild-type t-PA. Conclusion: Through the stimulation of plasminogen activation on a fibrin template and the inhibition of plasminogen activators and plasmin in the fluid phase, free fatty acids confine the action of fibrinolytic proteases to the site of clotting, where they partially oppose the thrombolytic barrier function of phospholipids. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text