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Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation
Published on: May 23, 2025
Selective triggering of platelet apoptosis, platelet activation or both
Armen V Gyulkhandanyan1, Asuman Mutlu, John Freedman
1Division of Transfusion Medicine, Department of Laboratory Medicine, Keenan Research Centre in the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, ON, Canada.
British Journal of Haematology
|February 13, 2013
Summary
Researchers developed a method to selectively trigger platelet apoptosis or activation. Different stimuli, like ABT-737 and thrombin, induced distinct platelet responses, crucial for hemostasis and clearance.
Area of Science:
- Hematology
- Cell Biology
- Pharmacology
Background:
- Anucleate platelets are vital for hemostasis and clearance.
- Platelet activation and apoptosis are fundamental processes.
- Understanding these processes is key to managing bleeding and clotting disorders.
Purpose of the Study:
- To develop a method for selective and concurrent stimulation of platelet apoptosis and/or activation.
- To investigate the differential mechanisms driving platelet apoptosis and activation.
- To provide a model for studying pharmacological manipulation of platelet responses.
Main Methods:
- Human platelets were treated with BH3 mimetic ABT-737, thrombin, and calcium ionophore A23187.
- Apoptosis was assessed by mitochondrial inner membrane potential (ΔΨm) depolarization.
- Activation was measured by P-selectin exposure.
Main Results:
- ABT-737 predominantly induced apoptosis (77-81% ΔΨm depolarization) in a time- and temperature-dependent manner at 37°C.
- Thrombin primarily induced activation (79-85% P-selectin exposure) within 15-90 min.
- A23187 triggered both apoptosis and activation (73-81%) under various conditions.
Conclusions:
- Platelet apoptosis and activation are distinct phenomena regulated by different mechanisms.
- The choice of stimulus dictates whether platelets undergo apoptosis only, activation only, or both.
- This model facilitates research into differential pharmacological control of platelet responses in hemostasis, thrombosis, and clearance.
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