1
|
Dysregulated Hemostasis and Immunothrombosis in Cerebral Cavernous Malformations. Int J Mol Sci 2022; 23:ijms232012575. [PMID: 36293431 PMCID: PMC9604397 DOI: 10.3390/ijms232012575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/17/2022] Open
Abstract
Cerebral cavernous malformation (CCM) is a neurovascular disease that affects 0.5% of the general population. For a long time, CCM research focused on genetic mutations, endothelial junctions and proliferation, but recently, transcriptome and proteome studies have revealed that the hemostatic system and neuroinflammation play a crucial role in the development and severity of cavernomas, with some of these publications coming from our group. The aim of this review is to give an overview of the latest molecular insights into the interaction between CCM-deficient endothelial cells with blood components and the neurovascular unit. Specifically, we underscore how endothelial dysfunction can result in dysregulated hemostasis, bleeding, hypoxia and neurological symptoms. We conducted a thorough review of the literature and found a field that is increasingly poised to regard CCM as a hemostatic disease, which may have implications for therapy.
Collapse
|
2
|
Abstract
Platelet-derived polyphosphates (polyP), stored in dense granule and released upon platelet activation, have been claimed to enhance thrombin activation of coagulation factor XI (FXI) and to activate FXII directly. The latter claim is controversial and principal results leading to these conclusions are probably influenced by methodological problems. It is important to consider that low-grade contact activation is initiated by all surfaces and is greatly amplified by the presence of phospholipids simulating the procoagulant membranes of activated platelets. Thus, proper use of inhibitors of the contact pathway and a careful choice of materials for plates and tubes is important to avoid artefacts. The use of phosphatases used to degrade polyP has an important drawback as it also degrades the secondary activators ADP and ATP, which are released from activated platelets. In addition, the use of positively charged inhibitors, such as polymyxin B, to inhibit polyP in platelet-rich plasma and blood is problematic, as polymyxin B also slows coagulation in the absence of polyP. In conclusion we hope awareness of the above caveats may improve research on the physiological roles of polyP in coagulation.
Collapse
|
3
|
FXIa and platelet polyphosphate as therapeutic targets during human blood clotting on collagen/tissue factor surfaces under flow. Blood 2015; 126:1494-502. [PMID: 26136249 DOI: 10.1182/blood-2015-04-641472] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/18/2015] [Indexed: 11/20/2022] Open
Abstract
Factor XIIa (FXIIa) and factor XIa (FXIa) contribute to thrombosis in animal models, whereas platelet-derived polyphosphate (polyP) may potentiate contact or thrombin-feedback pathways. The significance of these mediators in human blood under thrombotic flow conditions on tissue factor (TF) -bearing surfaces remains inadequately resolved. Human blood (corn trypsin inhibitor treated [4 μg/mL]) was tested by microfluidic assay for clotting on collagen/TF at TF surface concentration ([TF]wall) from ∼0.1 to 2 molecules per μm(2). Anti-FXI antibodies (14E11 and O1A6) or polyP-binding protein (PPXbd) were used to block FXIIa-dependent FXI activation, FXIa-dependent factor IX (FIX) activation, or platelet-derived polyP, respectively. Fibrin formation was sensitive to 14E11 at 0 to 0.1 molecules per µm(2) and sensitive to O1A6 at 0 to 0.2 molecules per µm(2). However, neither antibody reduced fibrin generation at ∼2 molecules per µm(2) when the extrinsic pathway became dominant. Interestingly, PPXbd reduced fibrin generation at low [TF]wall (0.1 molecules per µm(2)) but not at zero or high [TF]wall, suggesting a role for polyP distinct from FXIIa activation and requiring low extrinsic pathway participation. Regardless of [TF]wall, PPXbd enhanced fibrin sensitivity to tissue plasminogen activator and promoted clot retraction during fibrinolysis concomitant with an observed PPXbd-mediated reduction of fibrin fiber diameter. This is the first detection of endogenous polyP function in human blood under thrombotic flow conditions. When triggered by low [TF]wall, thrombosis may be druggable by contact pathway inhibition, although thrombolytic susceptibility may benefit from polyP antagonism regardless of [TF]wall.
Collapse
|
4
|
Zakharova NV, Artemenko EO, Podoplelova NA, Sveshnikova AN, Demina IA, Ataullakhanov FI, Panteleev MA. Platelet surface-associated activation and secretion-mediated inhibition of coagulation factor XII. PLoS One 2015; 10:e0116665. [PMID: 25688860 PMCID: PMC4331558 DOI: 10.1371/journal.pone.0116665] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 12/11/2014] [Indexed: 01/23/2023] Open
Abstract
Coagulation factor XII (fXII) is important for arterial thrombosis, but its physiological activation mechanisms are unclear. In this study, we elucidated the role of platelets and platelet-derived material in fXII activation. FXII activation was only observed upon potent platelet stimulation (with thrombin, collagen-related peptide, or calcium ionophore, but not ADP) accompanied by phosphatidylserine exposure and was localised to the platelet surface. Platelets from three patients with grey platelet syndrome did not activate fXII, which suggests that platelet-associated fXII-activating material might be released from α-granules. FXII was preferentially bound by phosphotidylserine-positive platelets and annexin V abrogated platelet-dependent fXII activation; however, artificial phosphotidylserine/phosphatidylcholine microvesicles did not support fXII activation under the conditions herein. Confocal microscopy using DAPI as a poly-phosphate marker did not reveal poly-phosphates associated with an activated platelet surface. Experimental data for fXII activation indicates an auto-inhibition mechanism (ki/ka = 180 molecules/platelet). Unlike surface-associated fXII activation, platelet secretion inhibited activated fXII (fXIIa), particularly due to a released C1-inhibitor. Platelet surface-associated fXIIa formation triggered contact pathway-dependent clotting in recalcified plasma. Computer modelling suggests that fXIIa inactivation was greatly decreased in thrombi under high blood flow due to inhibitor washout. Combined, the surface-associated fXII activation and its inhibition in solution herein may be regarded as a flow-sensitive regulator that can shift the balance between surface-associated clotting and plasma-dependent inhibition, which may explain the role of fXII at high shear and why fXII is important for thrombosis but negligible in haemostasis.
Collapse
Affiliation(s)
- Natalia V. Zakharova
- National Research Center for Hematology, Moscow, Russia
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - Elena O. Artemenko
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - Nadezhda A. Podoplelova
- National Research Center for Hematology, Moscow, Russia
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - Anastasia N. Sveshnikova
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Irina A. Demina
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - Fazly I. Ataullakhanov
- National Research Center for Hematology, Moscow, Russia
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
- Faculty of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Mikhail A. Panteleev
- National Research Center for Hematology, Moscow, Russia
- Center for Theoretical Problems of Physicochemical Pharmacology, Moscow, Russia
- Federal Research and Clinical Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
- Faculty of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- * E-mail:
| |
Collapse
|