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Kim OV, Litvinov RI, Gagne AL, French DL, Brass LF, Weisel JW. Megakaryocyte-induced contraction of plasma clots: cellular mechanisms and structural mechanobiology. Blood 2024; 143:548-560. [PMID: 37944157 PMCID: PMC11033616 DOI: 10.1182/blood.2023021545] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/17/2023] [Accepted: 11/02/2023] [Indexed: 11/12/2023] Open
Abstract
ABSTRACT Nonmuscle cell contractility is an essential feature underlying diverse cellular processes such as motility, morphogenesis, division and genome replication, intracellular transport, and secretion. Blood clot contraction is a well-studied process driven by contracting platelets. Megakaryocytes (MKs), which are the precursors to platelets, can be found in bone marrow and lungs. Although they express many of the same proteins and structures found in platelets, little is known about their ability to engage with extracellular proteins such as fibrin and contract. Here, we have measured the ability of MKs to compress plasma clots. Megakaryocytes derived from human induced pluripotent stem cells (iPSCs) were suspended in human platelet-free blood plasma and stimulated with thrombin. Using real-time macroscale optical tracking, confocal microscopy, and biomechanical measurements, we found that activated iPSC-derived MKs (iMKs) caused macroscopic volumetric clot shrinkage, as well as densification and stiffening of the fibrin network via fibrin-attached plasma membrane protrusions undergoing extension-retraction cycles that cause shortening and bending of fibrin fibers. Contraction induced by iMKs involved 2 kinetic phases with distinct rates and durations. It was suppressed by inhibitors of nonmuscle myosin IIA, actin polymerization, and integrin αIIbβ3-fibrin interactions, indicating that the molecular mechanisms of iMK contractility were similar or identical to those in activated platelets. Our findings provide new insights into MK biomechanics and suggest that iMKs can be used as a model system to study platelet contractility. Physiologically, the ability of MKs to contract plasma clots may play a role in the mechanical remodeling of intravascular blood clots and thrombi.
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Affiliation(s)
- Oleg V. Kim
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Department of Biomedical Engineering and Mechanics, Fralin Biomedical Research Institute, Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA
| | - Rustem I. Litvinov
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Alyssa L. Gagne
- Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA
| | - Deborah L. French
- Department of Pathology and Laboratory Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA
| | - Lawrence F. Brass
- Division of Hematology and Oncology, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - John W. Weisel
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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2
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Batten L, Sathyapalan T, Palmer TM. Molecular Mechanisms Linking Diabetes with Increased Risk of Thrombosis. Int J Mol Sci 2023; 24:17465. [PMID: 38139295 PMCID: PMC10744197 DOI: 10.3390/ijms242417465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 12/04/2023] [Accepted: 12/10/2023] [Indexed: 12/24/2023] Open
Abstract
This review will provide an overview of what is currently known about mechanisms linking poor glycaemic control with increased thrombotic risk. The leading causes of death in people with diabetes are strokes and cardiovascular disease. Significant morbidity is associated with an increased risk of thrombosis, resulting in myocardial infarction, ischaemic stroke, and peripheral vascular disease, along with the sequelae of these events, including loss of functional ability, heart failure, and amputations. While the increased platelet activity, pro-coagulability, and endothelial dysfunction directly impact this risk, the molecular mechanisms linking poor glycaemic control with increased thrombotic risk remain unclear. This review highlights the complex mechanisms underlying thrombosis prevalence in individuals with diabetes and hyperglycaemia. Post-translational modifications, such as O-GlcNAcylation, play a crucial role in controlling protein function in diabetes. However, the role of O-GlcNAcylation remains poorly understood due to its intricate regulation and the potential involvement of multiple variables. Further research is needed to determine the precise impact of O-GlcNAcylation on specific disease processes.
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Affiliation(s)
- Lucy Batten
- Biomedical Institute for Multimorbidity, Centre for Biomedicine, Hull York Medical School, University of Hull, Hull HU6 7RX, UK;
- Clinical Sciences Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - Thozhukat Sathyapalan
- Clinical Sciences Centre, Hull York Medical School, University of Hull, Hull HU6 7RX, UK
| | - Timothy M. Palmer
- Biomedical Institute for Multimorbidity, Centre for Biomedicine, Hull York Medical School, University of Hull, Hull HU6 7RX, UK;
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3
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Abstract
BACKGROUND We investigated the effects and mechanism of swimming on platelet function in mice fed with a high-fat diet. MATERIAL AND METHODS Mice were randomly divided into the control group (NC), high-fat group (HF), and high-fat diet combined with swimming group (FE). The FE group swam for 60 min a day, 5 days a week, for 8 weeks. RESULTS Compared with the NC group, the HF group had significant weight gain, dyslipidemia, abbreviated bleeding time after tail breakage, increased clot retraction, increased platelet aggregation rate, increased spread of platelets on fibrinogen, and increased pAKT level in platelets. Compared with the HF group, the FE group had lower body weight, improved dyslipidemia, prolonged bleeding time, reduced clot retraction, reduced platelet aggregation rate, decreased spread of platelets on fibrinogen, and decreased pAKT level in platelets. CONCLUSIONS By inhibiting the level of pAKT in platelets, swimming improves platelet dysfunction in mice fed with a high-fat diet.
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Affiliation(s)
- Xinyong Su
- Department of Physical Education, Binzhou Medical University, Yantai, China
| | - Xiao Yu
- Department of Physical Education, Binzhou Medical University, Yantai, China
| | - Ruzhuan Chen
- Department of Physical Education, Harbin University of Science and Technology Rongcheng Campus, Weihai, China
| | - Weihua Bian
- Department of Cell Biology, Binzhou Medical University, Yantai, China
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4
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Litvinov RI, Weisel JW. Blood clot contraction: Mechanisms, pathophysiology, and disease. Res Pract Thromb Haemost 2023; 7:100023. [PMID: 36760777 PMCID: PMC9903854 DOI: 10.1016/j.rpth.2022.100023] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/09/2022] [Accepted: 11/17/2022] [Indexed: 01/18/2023] Open
Abstract
A State of the Art lecture titled "Blood Clot Contraction: Mechanisms, Pathophysiology, and Disease" was presented at the International Society on Thrombosis and Haemostasis (ISTH) Congress in 2022. This was a systematic description of blood clot contraction or retraction, driven by activated platelets and causing compaction of the fibrin network along with compression of the embedded erythrocytes. The consequences of clot contraction include redistribution of the fibrin-platelet meshwork toward the periphery of the clot and condensation of erythrocytes in the core, followed by their deformation from the biconcave shape into polyhedral cells (polyhedrocytes). These structural signatures of contraction have been found in ex vivo thrombi derived from various locations, which indicated that clots undergo intravital contraction within the blood vessels. In hemostatic clots, tightly packed polyhedrocytes make a nearly impermeable seal that stems bleeding and is impaired in hemorrhagic disorders. In thrombosis, contraction facilitates the local blood flow by decreasing thrombus obstructiveness, reducing permeability, and changing susceptibility to fibrinolytic enzymes. However, in (pro)thrombotic conditions, continuous background platelet activation is followed by platelet exhaustion, refractoriness, and impaired intravital clot contraction, which is associated with weaker thrombi predisposed to embolization. Therefore, assays that detect imperfect in vitro clot contraction have potential diagnostic and prognostic values for imminent or ongoing thrombosis and thrombotic embolism. Collectively, the contraction of blood clots and thrombi is an underappreciated and understudied process that has a pathogenic and clinical significance in bleeding and thrombosis of various etiologies. Finally, we have summarized relevant new data on this topic presented during the 2022 ISTH Congress.
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Affiliation(s)
- Rustem I Litvinov
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - John W Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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5
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Baumann J, Sachs L, Otto O, Schoen I, Nestler P, Zaninetti C, Kenny M, Kranz R, von Eysmondt H, Rodriguez J, Schäffer TE, Nagy Z, Greinacher A, Palankar R, Bender M. Reduced platelet forces underlie impaired hemostasis in mouse models of MYH9-related disease. SCIENCE ADVANCES 2022; 8:eabn2627. [PMID: 35584211 PMCID: PMC9116608 DOI: 10.1126/sciadv.abn2627] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
MYH9-related disease patients with mutations in the contractile protein nonmuscle myosin heavy chain IIA display, among others, macrothrombocytopenia and a mild-to-moderate bleeding tendency. In this study, we used three mouse lines, each with one point mutation in the Myh9 gene at positions 702, 1424, or 1841, to investigate mechanisms underlying the increased bleeding risk. Agonist-induced activation of Myh9 mutant platelets was comparable to controls. However, myosin light chain phosphorylation after activation was reduced in mutant platelets, which displayed altered biophysical characteristics and generated lower adhesion, interaction, and traction forces. Treatment with tranexamic acid restored clot retraction in the presence of tPA and reduced bleeding. We verified our findings from the mutant mice with platelets from patients with the respective mutation. These data suggest that reduced platelet forces lead to an increased bleeding tendency in patients with MYH9-related disease, and treatment with tranexamic acid can improve the hemostatic function.
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Affiliation(s)
- Juliane Baumann
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | - Laura Sachs
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Oliver Otto
- Zentrum für Innovationskompetenz—Humorale Immunreaktionen bei Kardiovaskulären Erkrankungen, University Greifswald, Greifswald, Germany
- Deutsches Zentrum für Herz-Kreislauf-Forschung e. V., Standort Greifswald, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Ingmar Schoen
- School of Pharmacy and Biomolecular Sciences, Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Peter Nestler
- Zentrum für Innovationskompetenz—Humorale Immunreaktionen bei Kardiovaskulären Erkrankungen, University Greifswald, Greifswald, Germany
| | - Carlo Zaninetti
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
- University of Pavia, Pavia, Italy
| | - Martin Kenny
- School of Pharmacy and Biomolecular Sciences, Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Ruth Kranz
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | | | - Johanna Rodriguez
- Institute of Applied Physics, University of Tübingen, Tübingen, Germany
| | | | - Zoltan Nagy
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | - Andreas Greinacher
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Raghavendra Palankar
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
- Corresponding author. (M.B.); (R.P.)
| | - Markus Bender
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
- Corresponding author. (M.B.); (R.P.)
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6
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Xu Y, Yu G, Nie R, Wu Z. Microfluidic systems toward blood hemostasis monitoring and thrombosis diagnosis: From design principles to micro/nano fabrication technologies. VIEW 2022. [DOI: 10.1002/viw.20200183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Yi Xu
- Soft Intelligence Lab State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China
| | - Guang Yu
- Experimental Medicine Center Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China
| | - Ruqiong Nie
- Department of Cardiology Sun Yat‐Sen Memorial Hospital Sun Yat‐Sen University Guangzhou China
| | - Zhigang Wu
- Soft Intelligence Lab State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China
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7
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ROCK Inhibition as Potential Target for Treatment of Pulmonary Hypertension. Cells 2021; 10:cells10071648. [PMID: 34209333 PMCID: PMC8303917 DOI: 10.3390/cells10071648] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/17/2021] [Accepted: 06/23/2021] [Indexed: 02/07/2023] Open
Abstract
Pulmonary hypertension (PH) is a cardiovascular disease caused by extensive vascular remodeling in the lungs, which ultimately leads to death in consequence of right ventricle (RV) failure. While current drugs for PH therapy address the sustained vasoconstriction, no agent effectively targets vascular cell proliferation and tissue inflammation. Rho-associated protein kinases (ROCKs) emerged in the last few decades as promising targets for PH therapy, since ROCK inhibitors demonstrated significant anti-remodeling and anti-inflammatory effects. In this review, current aspects of ROCK inhibition therapy are discussed in relation to the treatment of PH and RV dysfunction, from cell biology to preclinical and clinical studies.
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8
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George MJ, Litvinov J, Aroom K, Spangler LJ, Caplan H, Wade CE, Cox CS, Gill BS. Microelectromechanical System Measurement of Platelet Contraction: Direct Interrogation of Myosin Light Chain Phosphorylation. Int J Mol Sci 2021; 22:ijms22126448. [PMID: 34208643 PMCID: PMC8234414 DOI: 10.3390/ijms22126448] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/11/2021] [Accepted: 06/12/2021] [Indexed: 12/16/2022] Open
Abstract
Myosin Light Chain (MLC) regulates platelet contraction through its phosphorylation by Myosin Light Chain Kinase (MLCK) or dephosphorylation by Myosin Light Chain Phosphatase (MLCP). The correlation between platelet contraction force and levels of MLC phosphorylation is unknown. We investigate the relationship between platelet contraction force and MLC phosphorylation using a novel microelectromechanical (MEMS) based clot contraction sensor (CCS). The MLCK and MLCP pair were interrogated by inhibitors and activators of platelet function. The CCS was fabricated from silicon using photolithography techniques and force was validated over a range of deflection for different chip spring constants. The force of platelet contraction measured by the clot contraction sensor (CCS) was compared to the degree of MLC phosphorylation by Western Blotting (WB) and ELISA. Stimulators of MLC phosphorylation produced higher contraction force, higher phosphorylated MLC signal in ELISA and higher intensity bands in WB. Inhibitors of MLC phosphorylation produced the opposite. Contraction force is linearly related to levels of phosphorylated MLC. Direct measurements of clot contractile force are possible using a MEMS sensor platform and correlate linearly with the degree of MLC phosphorylation during coagulation. Measured force represents the mechanical output of the actin/myosin motor in platelets regulated by myosin light chain phosphorylation.
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Affiliation(s)
- Mitchell J. George
- Department of Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (K.A.); (C.E.W.); (C.S.C.J.); (B.S.G.)
- Correspondence:
| | - Julia Litvinov
- Department of Pediatric Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (J.L.); (H.C.)
| | - Kevin Aroom
- Department of Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (K.A.); (C.E.W.); (C.S.C.J.); (B.S.G.)
| | | | - Henry Caplan
- Department of Pediatric Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (J.L.); (H.C.)
| | - Charles E. Wade
- Department of Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (K.A.); (C.E.W.); (C.S.C.J.); (B.S.G.)
| | - Charles S. Cox
- Department of Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (K.A.); (C.E.W.); (C.S.C.J.); (B.S.G.)
- Department of Pediatric Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (J.L.); (H.C.)
| | - Brijesh S. Gill
- Department of Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (K.A.); (C.E.W.); (C.S.C.J.); (B.S.G.)
- Department of Pediatric Surgery, McGovern Medical School at The University of Texas Health Science Center, Houston, TX 77030, USA; (J.L.); (H.C.)
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9
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Duan H, Khan GJ, Shang LJ, Peng H, Hu WC, Zhang JY, Hua J, Cassandra A, Rashed MM, Zhai KF. Computational pharmacology and bioinformatics to explore the potential mechanism of Schisandra against atherosclerosis. Food Chem Toxicol 2021; 150:112058. [DOI: 10.1016/j.fct.2021.112058] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/29/2021] [Accepted: 02/08/2021] [Indexed: 12/13/2022]
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10
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Pénzes M, Túrós D, Máthé D, Szigeti K, Hegedűs N, Rauscher AÁ, Tóth P, Ivic I, Padmanabhan P, Pál G, Dobolyi Á, Gyimesi M, Málnási-Csizmadia A. Direct myosin-2 inhibition enhances cerebral perfusion resulting in functional improvement after ischemic stroke. Theranostics 2020; 10:5341-5356. [PMID: 32373216 PMCID: PMC7196296 DOI: 10.7150/thno.42077] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 02/03/2020] [Indexed: 12/29/2022] Open
Abstract
Acute ischemic stroke treatment faces an unresolved obstacle as capillary reperfusion remains insufficient after thrombolysis and thrombectomy causing neuronal damage and poor prognosis. Hypoxia-induced capillary constriction is mediated by actomyosin contraction in precapillary smooth muscle cells (SMCs) therefore smooth muscle myosin-2 could be an ideal target with potentially high impact on reperfusion of capillaries. Methods: The myosin-2 inhibitor para-aminoblebbistatin (AmBleb) was tested on isolated human and rat arterioles to assess the effect of AmBleb on vasodilatation. Transient middle cerebral artery occlusion (MCAO) was performed on 38 male Wistar rats followed by local administration of AmBleb into the ischemic brain area. Development of brain edema and changes in cerebrovascular blood flow were assessed using MRI and SPECT. We also tested the neurological deficit scores and locomotor asymmetry of the animals for 3 weeks after the MCAO operation. Results: Our results demonstrate that AmBleb could achieve full relaxation of isolated cerebral arterioles. In living animals AmBleb recovered cerebral blood flow in 32 out of the 65 affected functional brain areas in MCAO operated rats, whereas only 8 out of the 67 affected areas were recovered in the control animals. Animals treated with AmBleb also showed significantly improved general and focal deficit scores in neurological functional tests and showed significantly ameliorated locomotor asymmetry. Conclusion: Direct inhibition of smooth muscle myosin by AmBleb in pre-capillary SMCs significantly contribute to the improvement of cerebral blood reperfusion and brain functions suggesting that smooth muscle myosin inhibition may have promising potential in stroke therapies as a follow-up treatment of physical or chemical removal of the occluding thrombus.
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11
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Obenaus AM, Mollica MY, Sniadecki NJ. (De)form and Function: Measuring Cellular Forces with Deformable Materials and Deformable Structures. Adv Healthc Mater 2020; 9:e1901454. [PMID: 31951099 PMCID: PMC7274881 DOI: 10.1002/adhm.201901454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/04/2019] [Indexed: 12/29/2022]
Abstract
The ability for biological cells to produce mechanical forces is important for the development, function, and homeostasis of tissue. The measurement of cellular forces is not a straightforward task because individual cells are microscopic in size and the forces they produce are at the nanonewton scale. Consequently, studies in cell mechanics rely on advanced biomaterials or flexible structures that permit one to infer these forces by the deformation they impart on the material or structure. Herein, the scientific progression on the use of deformable materials and deformable structures to measure cellular forces are reviewed. The findings and insights made possible with these approaches in the field of cell mechanics are summarized.
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Affiliation(s)
- Ava M Obenaus
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Molly Y Mollica
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Nathan J Sniadecki
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, USA
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98195, USA
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12
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Sachs L, Denker C, Greinacher A, Palankar R. Quantifying single-platelet biomechanics: An outsider's guide to biophysical methods and recent advances. Res Pract Thromb Haemost 2020; 4:386-401. [PMID: 32211573 PMCID: PMC7086474 DOI: 10.1002/rth2.12313] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/10/2019] [Accepted: 01/07/2020] [Indexed: 01/30/2023] Open
Abstract
Platelets are the key cellular components of blood primarily contributing to formation of stable hemostatic plugs at the site of vascular injury, thus preventing excessive blood loss. On the other hand, excessive platelet activation can contribute to thrombosis. Platelets respond to many stimuli that can be of biochemical, cellular, or physical origin. This drives platelet activation kinetics and plays a vital role in physiological and pathological situations. Currently used bulk assays are inadequate for comprehensive biomechanical assessment of single platelets. Individual platelets interact and respond differentially while modulating their biomechanical behavior depending on dynamic changes that occur in surrounding microenvironments. Quantitative description of such a phenomenon at single-platelet regime and up to nanometer resolution requires methodological approaches that can manipulate individual platelets at submicron scales. This review focusses on principles, specific examples, and limitations of several relevant biophysical methods applied to single-platelet analysis such as micropipette aspiration, atomic force microscopy, scanning ion conductance microscopy and traction force microscopy. Additionally, we are introducing a promising single-cell approach, real-time deformability cytometry, as an emerging biophysical method for high-throughput biomechanical characterization of single platelets. This review serves as an introductory guide for clinician scientists and beginners interested in exploring one or more of the above-mentioned biophysical methods to address outstanding questions in single-platelet biomechanics.
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Affiliation(s)
- Laura Sachs
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
| | | | - Andreas Greinacher
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
| | - Raghavendra Palankar
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
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13
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George MJ, Aroom KR, Wade CE, Cox CS, Gill BS. A Novel Platelet Function Assay for Trauma. J Surg Res 2019; 246:605-613. [PMID: 31668435 DOI: 10.1016/j.jss.2019.09.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 09/02/2019] [Accepted: 09/20/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND Platelet function tests such as thrombelastography platelet mapping and impedance aggregometry have demonstrated universal platelet dysfunction in trauma patients. In this study, we introduce the measurement of platelet contraction force as a test of platelet function. We hypothesize that force will correlate with established coagulation tests such as thrombelastography, demonstrate significant differences between healthy subjects and trauma patients, and identify critically ill trauma patients. METHODS Blood samples were prospectively collected from level 1 trauma patients at initial presentation, assayed for force of and time to contraction and compared with thrombelastography. Blood from healthy subjects was assayed to establish a reference range. Results from trauma patients were compared with healthy controls and trauma patients that died. RESULTS The study includes one hundred trauma patients with mean age 45 y, 74% were male, and median injury severity score of 14 ± 12. Patients that survived (n = 90) demonstrated significantly elevated platelet contraction force compared with healthy controls (n = 12) (6390 ± 2340 versus 4790 ± 470 μN, P = 0.043) and trauma patients that died (n = 10) (6390 ± 2340 versus 2860 ± 1830 μN, P = 0.0001). Elapsed time to start of platelet contraction was faster in trauma patients that survived compared with healthy controls (660 ± 467 versus 1130 ± 140 s, P = 0.0022) and those that died (660 ± 470 versus 1460 ± 1340 s, P < 0.0001). CONCLUSIONS In contrast with all existing platelet function tests reported in the literature, which report platelet dysfunction in trauma patients, contractile force demonstrates hyperfunction in surviving trauma patients and dysfunction in nonsurvivors. Platelet contraction reflects platelet metabolic reserve and thus may be a potential biomarker for survival after trauma. Contractile force warrants further investigation to predict mortality in severely injured trauma patients.
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Affiliation(s)
- Mitchell J George
- Department of Surgery, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas.
| | - Kevin R Aroom
- Department of Pediatric Surgery, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas
| | - Charles E Wade
- Department of Surgery, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas
| | - Charles S Cox
- Department of Pediatric Surgery, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas
| | - Brijesh S Gill
- Department of Surgery, McGovern Medical School, The University of Texas Health Science Center, Houston, Texas
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14
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Abstract
The vasculature is a dynamic environment in which blood platelets constantly survey the endothelium for sites of vessel damage. The formation of a mechanically coherent hemostatic plug to prevent blood loss relies on a coordinated series of ligand-receptor interactions governing the recruitment, activation, and aggregation of platelets. The physical biology of each step is distinct in that the recruitment of platelets depends on the mechanosensing of the platelet receptor glycoprotein Ib for the adhesive protein von Willebrand factor, whereas platelet activation and aggregation are responsive to the mechanical forces sensed at adhesive junctions between platelets and at the platelet-matrix interface. Herein we take a biophysical perspective to discuss the current understanding of platelet mechanotransduction as well as the measurement techniques used to quantify the physical biology of platelets in the context of thrombus formation under flow.
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Affiliation(s)
- Caroline E Hansen
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Children's Healthcare of Atlanta/Emory University School of Medicine, Atlanta, Georgia 30332, USA; .,Wallace H. Coulter Department of Biomedical Engineering and Institute for Electronics and Nanotechnology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
| | - Yongzhi Qiu
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Children's Healthcare of Atlanta/Emory University School of Medicine, Atlanta, Georgia 30332, USA; .,Wallace H. Coulter Department of Biomedical Engineering and Institute for Electronics and Nanotechnology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
| | - Owen J T McCarty
- Department of Cell, Developmental, and Cancer Biology, Oregon Health & Science University, Portland, Oregon 97239, USA.,Division of Hematology and Medical Oncology and Department of Biomedical Engineering, School of Medicine, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Wilbur A Lam
- Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Children's Healthcare of Atlanta/Emory University School of Medicine, Atlanta, Georgia 30332, USA; .,Wallace H. Coulter Department of Biomedical Engineering and Institute for Electronics and Nanotechnology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
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15
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Chen Y, Li Z, Ju LA. Tensile and compressive force regulation on cell mechanosensing. Biophys Rev 2019; 11:311-318. [PMID: 31073958 DOI: 10.1007/s12551-019-00536-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/25/2019] [Indexed: 12/14/2022] Open
Abstract
Receptor-mediated cell mechanosensing plays critical roles in cell spreading, migration, growth, and survival. Dynamic force spectroscopy (DFS) techniques have recently been advanced to visualize such processes, which allow the concurrent examination of molecular binding dynamics and cellular response to mechanical stimuli on single living cells. Notably, the live-cell DFS is able to manipulate the force "waveforms" such as tensile versus compressive, ramped versus clamped, static versus dynamic, and short versus long lasting forces, thereby deriving correlations of cellular responses with ligand binding kinetics and mechanical stimulation profiles. Here, by differentiating extracellular mechanical stimulations into two major categories, tensile force and compressive force, we review the latest findings on receptor-mediated mechanosensing mechanisms that are discovered by the state-of-the-art live-cell DFS technologies.
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Affiliation(s)
- Yunfeng Chen
- Department of Molecular Medicine, MERU-Roon Research Center on Vascular Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Zhiyong Li
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Lining Arnold Ju
- Heart Research Institute, Sydney, Australia. .,School of Aerospace, Mechanical and Mechatronic Engineering, Darlington, Australia. .,Charles Perkins Centre, The University of Sydney, Camperdown, NSW, 2006, Australia.
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16
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Qiu Y, Myers DR, Lam WA. The biophysics and mechanics of blood from a materials perspective. NATURE REVIEWS. MATERIALS 2019; 4:294-311. [PMID: 32435512 PMCID: PMC7238390 DOI: 10.1038/s41578-019-0099-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Cells actively interact with their microenvironment, constantly sensing and modulating biochemical and biophysical signals. Blood comprises a variety of non-adherent cells that interact with each other and with endothelial and vascular smooth muscle cells of the blood vessel walls. Blood cells are further experiencing a range of external forces by the hemodynamic environment and they also exert forces to remodel their local environment. Therefore, the biophysics and material properties of blood cells and blood play an important role in determining blood behaviour in health and disease. In this Review, we discuss blood cells and tissues from a materials perspective, considering the mechanical properties and biophysics of individual blood cells and endothelial cells as well as blood cell collectives. We highlight how blood vessels provide a mechanosensitive barrier between blood and tissues and how changes in vessel stiffness and flow shear stress can be correlated to plaque formation and exploited for the design of vascular grafts. We discuss the effect of the properties of fibrin on blood clotting, and investigate how forces exerted by platelets are correlated to disease. Finally, we hypothesize that blood and vascular cells are constantly establishing a mechanical homeostasis, which, when imbalanced, can lead to hematologic and vascular diseases.
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Affiliation(s)
- Yongzhi Qiu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - David R. Myers
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Wilbur A. Lam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Corresponding author,
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17
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Abstract
Platelet contraction provides a minimally invasive source for physiologic information. In this article, we describe a device that directly measures the kinetics of platelet contraction. Whole blood is injected between acrylic plates and an adherent clot forms. The bottom plate is fixed, and the top plate is attached to a wire cantilever. Platelet contraction drives deflection of the wire cantilever which is captured by a camera. Force generated by the clot with time is derived using beam equations. Force derivations were verified using a microelectromechanical (MEMS) force sensor. Kinetics of clot contraction were defined, including maximum contraction force (FMAX), lift-off time (TLIFTOFF), and contraction rate (CR). Metrics were compared with optical aggregometry and thromboelastography. FMAX correlates with optical aggregometry maximal amplitude with a Spearman's rho of 0.7904 and p = 0.0195 and thromboelastography maximal amplitude with a Spearman's rho of 0.8857 and p = 0.0188. Lift-off time correlates with optical aggregometry lag time with a Spearman's rho of 0.9048 and p = 0.002. This preliminary study demonstrates the repeatability of a useful platelet contraction device and its correlation with thromboelastography and optical aggregometry, the gold standard platelet function test.
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18
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Contractile forces in platelet aggregates under microfluidic shear gradients reflect platelet inhibition and bleeding risk. Nat Commun 2019; 10:1204. [PMID: 30867419 PMCID: PMC6416331 DOI: 10.1038/s41467-019-09150-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 02/13/2019] [Indexed: 12/21/2022] Open
Abstract
Platelets contract forcefully after their activation, contributing to the strength and stability of platelet aggregates and fibrin clots during blood coagulation. Viscoelastic approaches can be used to assess platelet-induced clot strengthening, but they require thrombin and fibrin generation and are unable to measure platelet forces directly. Here, we report a rapid, microfluidic approach for measuring the contractile force of platelet aggregates for the detection of platelet dysfunction. We find that platelet forces are significantly reduced when blood samples are treated with inhibitors of myosin, GPIb-IX-V, integrin αIIbβ3, P2Y12, or thromboxane generation. Clinically, we find that platelet forces are measurably lower in cardiology patients taking aspirin. We also find that measuring platelet forces can identify Emergency Department trauma patients who subsequently require blood transfusions. Together, these findings indicate that microfluidic quantification of platelet forces may be a rapid and useful approach for monitoring both antiplatelet therapy and traumatic bleeding risk. Platelet aggregates generate contractile forces that contribute to their cohesion and adhesion. Here, Ting et al. develop a microfluidic device to measure contractile forces generated by platelet aggregates, and find it can detect the response of platelets to pharmacological agents and predict bleeding risk in trauma patients.
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19
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Hanke J, Ranke C, Perego E, Köster S. Human blood platelets contract in perpendicular direction to shear flow. SOFT MATTER 2019; 15:2009-2019. [PMID: 30724316 DOI: 10.1039/c8sm02136h] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In their physiological environment, blood platelets are permanently exposed to shear forces caused by blood flow. Within this surrounding, they generate contractile forces that eventually lead to a compaction of the blood clot. Here, we present a microfluidic chamber that combines hydrogel-based traction force microscopy with a controlled shear environment, and investigate the force fields platelets generate when exposed to shear flow in a spatio-temporally resolved manner. We find that for shear rates between 14 s-1 to 33 s-1, the general contraction behavior in terms of force distribution and magnitude does not differ from no-flow conditions. The main direction of contraction, however, does respond to the externally applied stress. At high shear stress, we observe an angle of about 90° between flow direction and main contraction axis. We explain this observation by the distribution of the stress acting on the adherent cell: the observed angle provides the most stable situation for the cell experiencing the shear flow, as supported by a finite element method simulation of the stresses along the platelet boundary.
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Affiliation(s)
- Jana Hanke
- Institute for X-Ray Physics, University of Goettingen, 37077 Göttingen, Germany.
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20
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21
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Williams EK, Oshinowo O, Ravindran A, Lam WA, Myers DR. Feeling the Force: Measurements of Platelet Contraction and Their Diagnostic Implications. Semin Thromb Hemost 2018; 45:285-296. [PMID: 30566972 DOI: 10.1055/s-0038-1676315] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In addition to the classical biological and biochemical framework, blood clots can also be considered as active biomaterials composed of dynamically contracting platelets, nascent polymeric fibrin that functions as a matrix scaffold, and entrapped blood cells. As platelets sense, rearrange, and apply forces to the surrounding microenvironment, they dramatically change the material properties of the nascent clot, increasing its stiffness by an order of magnitude. Hence, the mechanical properties of blood clots are intricately tied to the forces applied by individual platelets. Research has also shown that the pathophysiological changes in clot mechanical properties are associated with bleeding and clotting disorders, cancer, stroke, ischemic heart disease, and more. By approaching the study of hemostasis and thrombosis from a biophysical and mechanical perspective, important insights have been made into how the mechanics of clotting and the forces applied by platelets are linked to various diseases. This review will familiarize the reader with a mechanics framework that is contextualized with relevant biology. The review also includes a discussion of relevant tools used to study platelet forces either directly or indirectly, and finally, concludes with a summary of potential links between clotting forces and disease.
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Affiliation(s)
- Evelyn Kendall Williams
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Aflac Cancer Center and Blood Disorders Service, Children's Healthcare of Atlanta, Emory University School of Medicine, Emory University, Atlanta, Georgia.,Winship Cancer Institute of Emory University, Emory University, Atlanta, Georgia.,Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia
| | - Oluwamayokun Oshinowo
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Aflac Cancer Center and Blood Disorders Service, Children's Healthcare of Atlanta, Emory University School of Medicine, Emory University, Atlanta, Georgia.,Winship Cancer Institute of Emory University, Emory University, Atlanta, Georgia.,Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia
| | - Abhijit Ravindran
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Aflac Cancer Center and Blood Disorders Service, Children's Healthcare of Atlanta, Emory University School of Medicine, Emory University, Atlanta, Georgia.,Winship Cancer Institute of Emory University, Emory University, Atlanta, Georgia.,Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia
| | - Wilbur A Lam
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Aflac Cancer Center and Blood Disorders Service, Children's Healthcare of Atlanta, Emory University School of Medicine, Emory University, Atlanta, Georgia.,Winship Cancer Institute of Emory University, Emory University, Atlanta, Georgia.,Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia
| | - David R Myers
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Aflac Cancer Center and Blood Disorders Service, Children's Healthcare of Atlanta, Emory University School of Medicine, Emory University, Atlanta, Georgia.,Winship Cancer Institute of Emory University, Emory University, Atlanta, Georgia.,Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia.,Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia
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22
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Rauscher AÁ, Gyimesi M, Kovács M, Málnási-Csizmadia A. Targeting Myosin by Blebbistatin Derivatives: Optimization and Pharmacological Potential. Trends Biochem Sci 2018; 43:700-713. [PMID: 30057142 DOI: 10.1016/j.tibs.2018.06.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 06/08/2018] [Accepted: 06/11/2018] [Indexed: 11/28/2022]
Abstract
Blebbistatin is a widely used inhibitor of myosin 2 that enables the study of a broad range of cytoskeleton-related processes. However, blebbistatin has several limitations hindering its applicability: it is fluorescent, poorly water soluble, cytotoxic, and prone to (photo)degradation. Despite these adverse effects, being the only available myosin 2-specific inhibitor, blebbistatin is rather a choice of necessity. Blebbistatin has been modified to improve its properties and some of the new compounds have proven to be useful replacements of the original molecule. This review summarizes recent results on blebbistatin development. We also discuss the pharmacological perspectives of these efforts, as myosins are becoming promising drug target candidates for a variety of conditions ranging from neurodegeneration to muscle disease, wound healing, and cancer metastasis.
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Affiliation(s)
- Anna Á Rauscher
- Motor Pharmacology Research Group, Department of Biochemistry, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Máté Gyimesi
- Motor Pharmacology Research Group, Department of Biochemistry, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Mihály Kovács
- Motor Pharmacology Research Group, Department of Biochemistry, Eötvös Loránd University, H-1117 Budapest, Hungary.
| | - András Málnási-Csizmadia
- Motor Pharmacology Research Group, Department of Biochemistry, Eötvös Loránd University, H-1117 Budapest, Hungary.
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23
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Finite Element Analysis of Tricuspid Valve Deformation from Multi-slice Computed Tomography Images. Ann Biomed Eng 2018; 46:1112-1127. [PMID: 29663193 DOI: 10.1007/s10439-018-2024-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 04/07/2018] [Indexed: 12/26/2022]
Abstract
Despite the growing clinical interest in the tricuspid valve (TV), there is an incomplete understanding of TV biomechanics which is important in normal TV function and successful TV repair techniques. Computational models with patient-specific human TV geometries can provide a quantitative understanding of TV biomechanic. Therefore, this study aimed to develop finite element (FE) models of human TVs from multi-slice computed tomography (MSCT) images to investigate chordal forces and leaflet stresses and strains. Three FE models were constructed for human subjects with healthy TVs from MSCT images and incorporated detailed leaflet geometries, realistic nonlinear anisotropic hyperelastic material properties of human TV, and physiological boundary conditions tracked from MSCT images. TV closure from diastole to systole was simulated. Chordal lengths were iteratively adjusted until the simulated TV geometries were in good agreement with the "true" geometries reconstructed from MSCT images at systole. Larger chordal forces were found on the strut (or basal) chords than on the rough zone chords and the total forces applied on the anterior papillary muscles by the strut chords were higher than those on the posterior or septal papillary muscles. At peak systolic pressure, the average maximum stress on the middle sections of the leaflets ranged from 30 to 90 kPa, while the average maximum principal strain values ranged from 0.16 to 0.30. The results from healthy TVs can serve as baseline biomechanical metrics of TV mechanics and may be used to inform TV repair device design. The computational approach developed could be one step towards developing computational models that may support pre-operative planning in complex TV repair procedures in the future.
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24
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George MJ, Burchfield J, MacFarlane B, Wang YWW, Cardenas JC, White NJ, Gill BS, Wade CE. Multiplate and TEG platelet mapping in a population of severely injured trauma patients. Transfus Med 2017; 28:224-230. [PMID: 28913856 DOI: 10.1111/tme.12473] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 08/17/2017] [Accepted: 08/21/2017] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The objectives of this study were to compare thromboelastography platelet mapping (TEG PM) with impedance aggregometry (Multiplate, MP) in a single trauma population and relate their results clinically. BACKGROUND Platelet function as measured by thromboelastography and impedance aggregometry demonstrates significant reductions that persist for days following traumatic injury. However, no study compares these devices and the correlation between them is not known. METHODS In level 1 trauma patients, TEG PM and MP were conducted at their initial presentation to the emergency department. Within-device repeatability and between-device association were determined using correlation analyses. Demographic variables, Injury Severity Score, blood product transfusion, laboratory test results and mortality rate were recorded. RESULTS Ninety-two patients were enrolled. Within-device repeatability was high for TEG PM and MP for arachidonic acid (AA) and adenosine diphosphate (ADP) activation pathways. When comparing TEG PM with MP, results correlated poorly in the ADP pathway (Spearman's rho = 0·11, P = 0·44) and moderately in the AA pathway (Spearman's rho = 0·56, P < 0·0001). TEG PM was predictive of blood product transfusion and correlated with increased base deficit, whereas MP was only predictive of mortality. CONCLUSIONS Intra-device variability was low for TEG PM and MP, but the two point-of-care devices measuring platelet function correlate poorly with each other in injured trauma patients. Each device also had different clinical associations.
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Affiliation(s)
- M J George
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - J Burchfield
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - B MacFarlane
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Y-W W Wang
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - J C Cardenas
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - N J White
- Department of Emergency Medicine, University of Washington, Seattle, Washington, USA
| | - B S Gill
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - C E Wade
- Center for Translational Injury Research, University of Texas Health Science Center at Houston, Houston, Texas, USA
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