Investigation Of Shear-sensitive Signalling Pathways In Human Platelets
Funder
National Health and Medical Research Council
Funding Amount
$196,527.00
Summary
Platelets are extremely important cells that control bleeding by sticking to injured blood vessels to form a blood clot. Excessive clotting can lead to fatal vascular events such as heart attacks and strokes. On the other hand, defects in blood clotting can result in life threatening bleeding problems. Platelets stick to the wall of a blood vessel when receptors on the surface of these cells interact with materials (ligands) that are exposed when the vessel wall is injured. The stickiness or adh ....Platelets are extremely important cells that control bleeding by sticking to injured blood vessels to form a blood clot. Excessive clotting can lead to fatal vascular events such as heart attacks and strokes. On the other hand, defects in blood clotting can result in life threatening bleeding problems. Platelets stick to the wall of a blood vessel when receptors on the surface of these cells interact with materials (ligands) that are exposed when the vessel wall is injured. The stickiness or adhesive behaviour of platelets is controlled by many proteins (enzymes) which are contained inside these cells. These enzymes transmit messages from platelet receptors on the surface into the cell interior, thereby controlling platelet behaviour. We are in the process of identifying several types of enzymes which are responsible for controlling platelet stickiness. Our research will provide a better understanding of the complicated pathways regulating platelet stickiness and clot formation. The knowledge gained from these studies may ultimately asssist in the design of specific drugs for the prevention and-or treatment of heart attacks and strokes.Read moreRead less
Investigating The Link Between Oxidative Stress And Biomechanical Integrin Activation In Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$653,742.00
Summary
Diabetes represents a serious healthcare problem globally. A large proportion of deaths associated with diabetes can be attributed to the development of blood clots in the circulation of the heart and brain (heart attack/stroke). The blood clotting mechanism is ‘hyperactive’ in diabetes, although the reason for this is not well defined. In this proposal we will investigate a new mechanism promoting blood clots, and will investigate innovative approaches to reduce this clotting mechanism.
Regulation Of Receptors That Control Platelet Function Under Shear Stress
Funder
National Health and Medical Research Council
Funding Amount
$507,273.00
Summary
Specialized human blood cells that control blood loss and clotting (platelets) are currently difficult to test in the clinical laboratory, meaning patients are at risk of excessive bleeding or serious clot formation during disease or treatment. The aim of this proposal is to use our new reagents and assays to develop more reliable methods for evaluating relative bleeding or clotting risk in individuals.
Identification Of A Novel Adhesion Mechanism Regulating Platelet-endothelial Interactions.
Funder
National Health and Medical Research Council
Funding Amount
$501,691.00
Summary
Platelets are important blood cells, stopping bleeding in the event of blood vessel injury. However, platelets can also interact with the blood vessel lining (endothelium) to regulate and in some cases promote inflammation. We have identified a new structure platelets use to stick to endothelium, which under disease states (enhanced oxidative stress), can promote inflammation. We will investigate how tractopods form, and examine their role in the setting of elevated oxidative stress and inflamma ....Platelets are important blood cells, stopping bleeding in the event of blood vessel injury. However, platelets can also interact with the blood vessel lining (endothelium) to regulate and in some cases promote inflammation. We have identified a new structure platelets use to stick to endothelium, which under disease states (enhanced oxidative stress), can promote inflammation. We will investigate how tractopods form, and examine their role in the setting of elevated oxidative stress and inflammatory disease.Read moreRead less
Ligand Interactions Of Platelet Glycoprotein Ib-IX-V In Thrombosis
Funder
National Health and Medical Research Council
Funding Amount
$363,098.00
Summary
The transition of circulating blood platelets from a fluid-phase, non-adherent state to an adherent, activated and aggregated state (thrombus formation) is critical in the normal haemostatic response to blood vessel injury and in thrombotic diseases such as heart attack and stroke. One unique platelet receptor, the glycoprotein Ib-IX-V complex, is of particular interest, because it initiates platelet aggregate or thrombus formation at high fluid shear stress in flowing blood, including the patho ....The transition of circulating blood platelets from a fluid-phase, non-adherent state to an adherent, activated and aggregated state (thrombus formation) is critical in the normal haemostatic response to blood vessel injury and in thrombotic diseases such as heart attack and stroke. One unique platelet receptor, the glycoprotein Ib-IX-V complex, is of particular interest, because it initiates platelet aggregate or thrombus formation at high fluid shear stress in flowing blood, including the pathological shear stress that occurs in a sclerotic coronary artery. Our published and preliminary results show how GPIb-dependent interaction of platelets with von Willebrand factor, the major adhesive ligand for GPIb-IX-V, is dependent on the level of shear stress. Using a cross-species (human to canine) homology-swap approach, where human sequence is replaced by the corresponding canine sequence within discrete structural domains, a sequence of GPIb has been identified which becomes increasingly important as hydrodynamic shear stress increases. It is proposed to further define the interactive surface of GPIb that recognizes von Willebrand factor at increasing shear, and to define the relationship between the shear-dependent alteration of GPIb conformation and its ability to interact with other pro-thrombotic or pro-inflammatory binding partners.Read moreRead less
The Role Of The Platelet Glycoprotein Ib Alpha Cytoplasmic Domain In Thrombosis
Funder
National Health and Medical Research Council
Funding Amount
$600,230.00
Summary
Our studies aim to provide a better understanding of the factors that make platelets sticky, because this is important not only for normal blood clot formation but also in the development of harmful blood clots (thrombosis). Improving our understanding of these processes will add significantly to our knowledge of how blood clotting is controlled. This information is relevant to many human diseases including heart attack and stroke and will help us to develop drugs to prevent these diseases.
Investigating A Potential New Treatment For Stroke
Funder
National Health and Medical Research Council
Funding Amount
$878,522.00
Summary
Blood clots blocking blood flow to the brain (stroke) are a major cause of death and disability. Safety concerns limit approved therapies to a small subset of patients, highlighting an urgent need for safer, more effective drugs. Our studies show that inhibitors of the enzyme PI3Kbeta increase blood clot permeability, increasing clot ‘dissolvability’, without increased bleeding. This raises the possibility that PI3Kbeta inhibitors may represent a safe and effective adjuvant therapy for stroke.