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Zhao C, Zhou T, Li M, Liu J, Zhao X, Pang Y, Liu X, Zhang J, Ma L, Li W, Yao X, Feng S. Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway. Neural Regen Res 2024; 19:434-439. [PMID: 37488908 PMCID: PMC10503625 DOI: 10.4103/1673-5374.375345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 12/28/2022] [Accepted: 03/29/2023] [Indexed: 07/26/2023] Open
Abstract
Argatroban is a synthetic thrombin inhibitor approved by U.S. Food and Drug Administration for the treatment of thrombosis. However, whether it plays a role in the repair of spinal cord injury is unknown. In this study, we established a rat model of T10 moderate spinal cord injury using an NYU Impactor Moder III and performed intraperitoneal injection of argatroban for 3 consecutive days. Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord. RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway, which is involved in astrogliosis and glial scar formation. Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway. Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord. Taken together, these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway, thereby promoting the recovery of neurological function after spinal cord injury.
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Affiliation(s)
- Chenxi Zhao
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Tiangang Zhou
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Ming Li
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Jie Liu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Xiaoqing Zhao
- Orthopedic Research Center of Shandong University, Cheeloo College of Medicine, Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong Province, China
| | - Yilin Pang
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Xinjie Liu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Jiawei Zhang
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Lei Ma
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Wenxiang Li
- Orthopedic Research Center of Shandong University, Cheeloo College of Medicine, Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong Province, China
| | - Xue Yao
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- Orthopedic Research Center of Shandong University, Cheeloo College of Medicine, Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong Province, China
| | - Shiqing Feng
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
- Orthopedic Research Center of Shandong University, Cheeloo College of Medicine, Department of Orthopedics, Qilu Hospital of Shandong University, Jinan, Shandong Province, China
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Shlobin NA, Har-Even M, Itsekson-Hayosh Z, Harnof S, Pick CG. Role of Thrombin in Central Nervous System Injury and Disease. Biomolecules 2021; 11:562. [PMID: 33921354 PMCID: PMC8070021 DOI: 10.3390/biom11040562] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/04/2021] [Accepted: 04/07/2021] [Indexed: 12/16/2022] Open
Abstract
Thrombin is a Na+-activated allosteric serine protease of the chymotrypsin family involved in coagulation, inflammation, cell protection, and apoptosis. Increasingly, the role of thrombin in the brain has been explored. Low concentrations of thrombin are neuroprotective, while high concentrations exert pathological effects. However, greater attention regarding the involvement of thrombin in normal and pathological processes in the central nervous system is warranted. In this review, we explore the mechanisms of thrombin action, localization, and functions in the central nervous system and describe the involvement of thrombin in stroke and intracerebral hemorrhage, neurodegenerative diseases, epilepsy, traumatic brain injury, and primary central nervous system tumors. We aim to comprehensively characterize the role of thrombin in neurological disease and injury.
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Affiliation(s)
- Nathan A. Shlobin
- Department of Neurological Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Meirav Har-Even
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
- Sylvan Adams Sports Institute, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Ze’ev Itsekson-Hayosh
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel;
- Department of Neurology and Joseph Sagol Neuroscience Center, The Chaim Sheba Medical Center, Tel HaShomer 5262000, Israel
| | - Sagi Harnof
- Department of Neurosurgery, Beilinson Hospital, Rabin Medical Center, Tel Aviv University, Petah Tikva 4941492, Israel;
| | - Chaim G. Pick
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
- Sylvan Adams Sports Institute, Tel Aviv University, Tel Aviv 6997801, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
- Center for Biology of Addictive Diseases, Tel Aviv University, Tel Aviv 6997801, Israel
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3
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Rohatgi T, Sedehizade F, Reymann KG, Reiser G. Protease-Activated Receptors in Neuronal Development, Neurodegeneration, and Neuroprotection: Thrombin as Signaling Molecule in the Brain. Neuroscientist 2016; 10:501-12. [PMID: 15534036 DOI: 10.1177/1073858404269955] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Protease-activated receptors (PARs) belong to the superfamily of seven transmembrane domain G protein-coupled receptors. Four PAR subtypes are known, PAR-1 to -4. PARs are highly homologous between the species and are expressed in a wide variety of tissues and cell types. Of particular interest is the role which these receptors play in the brain, with regard to neuroprotection or degeneration under pathological conditions. The main agonist of PARs is thrombin, a multifunctional serine protease, known to be present not only in blood plasma but also in the brain. PARs possess an irreversible activation mechanism. Binding of agonist and subsequent cleavage of the extracellular N-terminus of the receptor results in exposure of a so-called tethered ligand domain, which then binds to extracellular loop 2 of the receptor leading to receptor activation. PARs exhibit an extensive expression pattern in both the central and the peripheral nervous system. PARs participate in several mechanisms important for normal cellular functioning and during critical situations involving cellular survival and death. In the last few years, research on Alzheimer’s disease and stroke has linked PARs to the pathophysiology of these neurodegenerative disorders. Actions of thrombin are concentration-dependent, and therefore, depending on cellular function and environment, serve as a double-edged sword. Thrombin can be neuroprotective during stress conditions, whereas under normal conditions high concentrations of thrombin are toxic to cells.
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Affiliation(s)
- Tanuja Rohatgi
- Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Magdeburg, Germany
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The Importance of Thrombin in Cerebral Injury and Disease. Int J Mol Sci 2016; 17:ijms17010084. [PMID: 26761005 PMCID: PMC4730327 DOI: 10.3390/ijms17010084] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 12/28/2015] [Accepted: 12/30/2015] [Indexed: 12/31/2022] Open
Abstract
There is increasing evidence that prothrombin and its active derivative thrombin are expressed locally in the central nervous system. So far, little is known about the physiological and pathophysiological functions exerted by thrombin in the human brain. Extra-hepatic prothrombin expression has been identified in neuronal cells and astrocytes via mRNA measurement. The actual amount of brain derived prothrombin is expected to be 1% or less compared to that in the liver. The role in brain injury depends upon its concentration, as higher amounts cause neuroinflammation and apoptosis, while lower concentrations might even be cytoprotective. Its involvement in numerous diseases like Alzheimer’s, multiple sclerosis, cerebral ischemia and haemorrhage is becoming increasingly clear. This review focuses on elucidation of the cerebral thrombin expression, local generation and its role in injury and disease of the central nervous system.
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Mirante O, Price M, Puentes W, Castillo X, Benakis C, Thevenet J, Monard D, Hirt L. Endogenous protease nexin-1 protects against cerebral ischemia. Int J Mol Sci 2013; 14:16719-31. [PMID: 23949634 PMCID: PMC3759934 DOI: 10.3390/ijms140816719] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 07/31/2013] [Accepted: 08/01/2013] [Indexed: 11/16/2022] Open
Abstract
The serine protease thrombin plays a role in signalling ischemic neuronal death in the brain. Paradoxically, endogenous neuroprotective mechanisms can be triggered by preconditioning with thrombin (thrombin preconditioning, TPC), leading to tolerance to cerebral ischemia. Here we studied the role of thrombin’s endogenous potent inhibitor, protease nexin-1 (PN-1), in ischemia and in tolerance to cerebral ischemia induced by TPC. Cerebral ischemia was modelled in vitro in organotypic hippocampal slice cultures from rats or genetically engineered mice lacking PN-1 or with the reporter gene lacZ knocked into the PN-1 locus PN-1HAPN-1-lacZ/HAPN-1-lacZ (PN-1 KI) exposed to oxygen and glucose deprivation (OGD). We observed increased thrombin enzyme activity in culture homogenates 24 h after OGD. Lack of PN-1 increased neuronal death in the CA1, suggesting that endogenous PN-1 inhibits thrombin-induced neuronal damage after ischemia. OGD enhanced β-galactosidase activity, reflecting PN-1 expression, at one and 24 h, most strikingly in the stratum radiatum, a glial cell layer adjacent to the CA1 layer of ischemia sensitive neurons. TPC, 24 h before OGD, additionally increased PN-1 expression 1 h after OGD, compared to OGD alone. TPC failed to induce tolerance in cultures from PN-1−/− mice confirming PN-1 as an important TPC target. PN-1 upregulation after TPC was blocked by the c-Jun N-terminal kinase (JNK) inhibitor, L-JNKI1, known to block TPC. This work suggests that PN-1 is an endogenous neuroprotectant in cerebral ischemia and a potential target for neuroprotection.
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Affiliation(s)
- Osvaldo Mirante
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Melanie Price
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Wilfredo Puentes
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Ximena Castillo
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Corinne Benakis
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Jonathan Thevenet
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
| | - Denis Monard
- Friedrich Miescher Institute for Biomedical Research, Basel 4058, Switzerland; E-Mail:
| | - Lorenz Hirt
- Stroke Laboratory, Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and Lausanne University, Lausanne 1011, Switzerland; E-Mails: (O.M.); (M.P.); (W.P.); (X.C.); (C.B.); (J.T.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +41-21-314-12-68; Fax: +41-21-314-12-90
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Wlodarczyk J, Mukhina I, Kaczmarek L, Dityatev A. Extracellular matrix molecules, their receptors, and secreted proteases in synaptic plasticity. Dev Neurobiol 2012; 71:1040-53. [PMID: 21793226 DOI: 10.1002/dneu.20958] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neural cells secrete diverse molecules, which accumulate in the extracellular space and form the extracellular matrix (ECM). Interactions between cells and the ECM are well recognized to play the crucial role in cell migration and guidance of growing axons, whereas formation of mature neural ECM in the form of perineuronal nets is believed to restrict certain forms of developmental plasticity. On the other hand, major components of perineuronal nets and other ECM molecules support induction of functional plasticity, the most studied form of which is long-term potentiation. Here, we review the underlying mechanisms by which ECM molecules, their receptors and remodeling proteases regulate the induction and maintenance of synaptic modifications. In particular, we highlight that activity-dependent secretion and activation of proteases leads to a local cleavage of the ECM and release of signaling proteolytic fragments. These molecules regulate transmitter receptor trafficking, actin cytoskeleton, growth of dendritic spines, and formation of dendritic filopodia.
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Thevenet J, Angelillo-Scherrer A, Price M, Hirt L. Coagulation factor Xa activates thrombin in ischemic neural tissue. J Neurochem 2009; 111:828-36. [PMID: 19719823 DOI: 10.1111/j.1471-4159.2009.06369.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thrombin is involved in mediating neuronal death in cerebral ischemia. We investigated its so far unknown mode of activation in ischemic neural tissue. We used an in vitro approach to distinguish the role of circulating coagulation factors from endogenous cerebral mechanisms. We modeled ischemic stroke by subjecting rat organotypic hippocampal slice cultures to 30-min oxygen (5%) and glucose (1 mmol/L) deprivation (OGD). Perinuclear activated factor X (FXa) immunoreactivity was observed in CA1 neurons after OGD. Selective FXa inhibition by fondaparinux during and after OGD significantly reduced neuronal death in the CA1 after 48 h. Thrombin enzyme activity was increased in the medium 24 h after OGD and this increase was prevented by fondaparinux suggesting that FXa catalyzes the conversion of prothrombin to thrombin in neural tissue after ischemia in vitro. Treatment with SCH79797, a selective antagonist of the thrombin receptor protease-activated receptor-1 (PAR-1), significantly decreased neuronal cell death indicating that thrombin signals ischemic damage via PAR-1. The c-Jun N-terminal kinase (JNK) pathway plays an important role in excitotoxicity and cerebral ischemia and we observed activation of the JNK substrate, c-Jun in our model. Both the FXa inhibitor, fondaparinux and the PAR-1 antagonist SCH79797, decreased the level of phospho-c-Jun Ser73. These results indicate that FXa activates thrombin in cerebral ischemia, which leads via PAR-1 to the activation of the JNK pathway resulting in neuronal death.
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Affiliation(s)
- Jonathan Thevenet
- Neurology Laboratory, Neurology Service, CHUV (Centre Hospitalier Universitaire Vaudois) and Lausanne University, Lausanne, Switzerland
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Laskowski A, Reiser G, Reymann KG. Protease-activated receptor-1 induces generation of new microglia in the dentate gyrus of traumatised hippocampal slice cultures. Neurosci Lett 2007; 415:17-21. [PMID: 17324513 DOI: 10.1016/j.neulet.2006.12.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 11/29/2006] [Accepted: 12/11/2006] [Indexed: 10/23/2022]
Abstract
The protease thrombin is not only known as a major component in the blood coagulation cascade but is also involved in proinflammatory processes in the central nervous system (CNS). Here we used an in vitro model, to investigate the effect of thrombin and protease-activated receptor-1 (PAR-1) on proliferation and microgliosis after traumatic injury. A 5-day exposure to thrombin after cutting the Schaffer collaterals induced a proliferation and microgliosis in the dentate gyrus of organotypic slice cultures. This effect is at least partially mediated by PAR-1 since the selective peptide agonist TRag shows similar effects. Thus, thrombin effects after injury might involve microglial proliferation.
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Affiliation(s)
- Alexandra Laskowski
- Leibniz Institut für Neurobiologie, Brennecke Str. 6, 39118 Magdeburg, Germany
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Xue M, Balasubramaniam J, Parsons KAL, McIntyre IW, Peeling J, Del Bigio MR. Does thrombin play a role in the pathogenesis of brain damage after periventricular hemorrhage? Brain Pathol 2005; 15:241-9. [PMID: 16196391 PMCID: PMC8096014 DOI: 10.1111/j.1750-3639.2005.tb00527.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Neonatal periventricular hemorrhage (PVH) is a devastating complication of prematurity in the human infant. Based upon observations made primarily in adult rodents and the fact that the immature brain uses proteolytic systems for cell migration and growth, we hypothesized that thrombin and plasmin enzyme activities contribute to the brain damage after PVH. The viability of mixed brain cells derived from newborn rat periventricular region was suppressed by whole blood and thrombin, but not plasmin. Following injection of autologous blood into the periventricular region of newborn rat brain, proteolytic activity was detected in a halo around the hematoma using membrane overlays impregnated with thrombin and plasmin fluorogenic substrates. Two-day old rats received periventricular injection of blood, thrombin, and plasminogen. After 2 days, thrombin and blood were associated with significantly greater damage than saline or plasminogen. Two-day old mice received intracerebral injections of blood in combination with saline or the proteolytic inhibitors hirudin, alpha2macroglobulin, or plasminogen activator inhibitor-1. After 2 days, hirudin significantly reduced brain cell death and inflammation. Two-day-old mice then received low and high doses of hirudin mixed with blood after which behavioral testing was conducted repeatedly. At 10 weeks there was no statistically significant evidence for behavioral or structural brain protection. These results indicate that thrombin likely plays a role in neonatal periventricular brain damage following PVH. However, additional factors are likely important in the recovery from this result.
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Affiliation(s)
- Mengzhou Xue
- Departments of Pathology, University of Manitoba, Winnipeg, Canada
- Manitoba Institute of Child Health, Winnipeg, Canada
| | - Janani Balasubramaniam
- Departments of Pathology, University of Manitoba, Winnipeg, Canada
- Manitoba Institute of Child Health, Winnipeg, Canada
| | | | | | - James Peeling
- Departments of Radiology, University of Manitoba, Winnipeg, Canada
| | - Marc R. Del Bigio
- Departments of Pathology, University of Manitoba, Winnipeg, Canada
- Manitoba Institute of Child Health, Winnipeg, Canada
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Abstract
A number of molecules have been postulated to be involved in long-term potentiation, an experimental model for learning and short-term memory. Although the molecular mechanisms of the long-term potentiation have been considerably well understood, it is not yet known why and how real memory can last very long with outstanding stability. A mechanical change of synaptic morphology at acquisition, consolidation and retention of memory is hypothesized to explain long-lasting memory. Changes in the synaptic morphology may be due, at least in part, to local extracellular proteolysis of cell adhesion and extracellular matrix molecules. Some extracellular serine proteases of the Clan PA family may modulate synaptic adhesion and associate with long-term potentiation and learning behavior. In the present review, candidate proteases that are involved in the hippocampal memory are overviewed.
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Affiliation(s)
- Sadao Shiosaka
- Division of Structural Cell Biology, Nara Institute of Science and Technology, Ikoma, Nara, Japan.
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Medina MG, Ledesma MD, Domínguez JE, Medina M, Zafra D, Alameda F, Dotti CG, Navarro P. Tissue plasminogen activator mediates amyloid-induced neurotoxicity via Erk1/2 activation. EMBO J 2005; 24:1706-16. [PMID: 15861134 PMCID: PMC1142582 DOI: 10.1038/sj.emboj.7600650] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2004] [Accepted: 03/24/2005] [Indexed: 11/09/2022] Open
Abstract
Tissue plasminogen activator (tPA) is the main activator of plasminogen into plasmin in the brain where it may have beneficial roles but also neurotoxic effects that could be plasmin dependent or not. Little is known about the substrates and pathways that mediate plasmin-independent tPA neurotoxicity. Here we show in primary hippocampal neurons that tPA promotes a catalytic-independent activation of the extracellular regulated kinase (Erk)1/2 signal transduction pathway through the N-methyl-D-aspartate receptor, G-proteins and protein kinase C. This results in GSK3 activation in a process that requires de novo synthesis of proteins, and leads to tau aberrant phosphorylation, microtubule destabilization and apoptosis. Similar effects are produced by amyloid aggregates in a tPA-dependent manner, as demonstrated by pharmacological treatments and in wt and tPA-/- mice neurons. Consistently, in Alzheimer's disease (AD) patients' brains, high levels of tPA colocalize with amyloid-rich areas, activated Erk1/2 and phosphorylated tau. This is the first demonstration of an intracellular pathway by which tPA triggers kinase activation, tau phosphorylation and neurotoxicity, suggesting a key role for this molecule in AD pathology.
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Affiliation(s)
- Manel G Medina
- Unitat de Biologia Cel.lular i Molecular, IMIM, Barcelona, Spain
| | - Maria Dolores Ledesma
- Cavalieri Ottolenghi Scientific Institute, Universita degli Studi di Torino, Orbassano (Turin), Italy
| | | | | | - Delia Zafra
- IRBB-Parc Científic, Universitat de Barcelona, Barcelona, Spain
| | - Francesc Alameda
- Departament Anatomia Patológica, Hospital del Mar, Barcelona, Spain
| | - Carlos G Dotti
- Cavalieri Ottolenghi Scientific Institute, Universita degli Studi di Torino, Orbassano (Turin), Italy
| | - Pilar Navarro
- Unitat de Biologia Cel.lular i Molecular, IMIM, Barcelona, Spain
- Unitat Biologia Cel.lular i Molecular, Institut Municipal d'Investigació Mèdica, Dr Aiguader, 80, 08003 Barcelona, Spain. Tel.: +34 93 2211009; Fax: +34 93 2213237; E-mail:
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12
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Abstract
Tissue plasminogen activator (tPA) is the only FDA-approved treatment of thrombotic stroke and is a major parenchymal serine protease in the brain. However, it has been implicated in a plethora of brain pathologies, raising concern about its use as a safe therapeutic. tPA is thought to regulate physiological processes that entail tissue remodeling and plasticity, purportedly due to its ability to initiate the degradation of extracellular matrix proteins and possibly other substrates. Understanding the physiological role(s) of tPA promises to both elucidate important aspects of brain function and improve the available therapies for neurological disease. In this context, the effects of tPA on glial cells, mainly microglial cells, but also astrocytes and Schwann cells, appear to be of particular importance, given the increasing awareness of the significance of glia in brain physiology and pathology
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Affiliation(s)
- Iordanis Gravanis
- Program in Molecular and Cellular Pharmacology and Department of Pharmacological Sciences, University Medical Center at Stony Brook, Stony Brook, New York 11794-8651, USA
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