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Antonijevic M, Sopkova-de Oliveira Santos J, Dallemagne P, Rochais C. Discovery of a pocket network on the domain 5 of the TrkB receptor - A potential new target in the quest for the new ligands. Mol Inform 2024; 43:e202400043. [PMID: 38619318 DOI: 10.1002/minf.202400043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/06/2024] [Accepted: 03/26/2024] [Indexed: 04/16/2024]
Abstract
The important role that the neurotrophin tyrosine kinase receptor - TrkB has in the pathogenesis of several neurodegenerative conditions such are Alzheimer's disease, Parkinson's disease, Huntington's disease, has been well described. This shouldn't be a surprise, since in the physiological conditions, once activated by brain-derived neurotrophic factor (BDNF) and neurotrophin-4/5 (NT-4/5), the TrkB receptor promotes neuronal survival, differentiation and synaptic function. Considering that the natural ligands for TrkB receptor are large proteins, it is a challenge to discover small molecule capable to mimic their effects. Even though, the surface of receptor that is interacting with BDNF or NT-4/5 is known, there was always a question which pocket and interaction is responsible for activation of it. In order to answer this challenging question, we have used molecular dynamic (MD) simulations and Pocketron algorithm which enabled us to detect, for the first time, a pocket network existing in the interacting domain (d5) of the receptor; to describe them and to see how they are communicating with each other. This new discovery gave us potential new areas on receptor that can be targeted and used for structure-based drug design approach in the development of the new ligands.
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Enkavi G, Girych M, Moliner R, Vattulainen I, Castrén E. TrkB transmembrane domain: bridging structural understanding with therapeutic strategy. Trends Biochem Sci 2024; 49:445-456. [PMID: 38433044 DOI: 10.1016/j.tibs.2024.02.001] [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: 10/30/2023] [Revised: 01/19/2024] [Accepted: 02/09/2024] [Indexed: 03/05/2024]
Abstract
TrkB (neuronal receptor tyrosine kinase-2, NTRK2) is the receptor for brain-derived neurotrophic factor (BDNF) and is a critical regulator of activity-dependent neuronal plasticity. The past few years have witnessed an increasing understanding of the structure and function of TrkB, including its transmembrane domain (TMD). TrkB interacts with membrane cholesterol, which bidirectionally regulates TrkB signaling. Additionally, TrkB has recently been recognized as a binding target of antidepressant drugs. A variety of different antidepressants, including typical and rapid-acting antidepressants, as well as psychedelic compounds, act as allosteric potentiators of BDNF signaling through TrkB. This suggests that TrkB is the common target of different antidepressant compounds. Although more research is needed, current knowledge suggests that TrkB is a promising target for further drug development.
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Affiliation(s)
- Giray Enkavi
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Mykhailo Girych
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Rafael Moliner
- Neuroscience Center/HiLIFE, University of Helsinki, Helsinki, Finland
| | - Ilpo Vattulainen
- Department of Physics, University of Helsinki, Helsinki, Finland.
| | - Eero Castrén
- Neuroscience Center/HiLIFE, University of Helsinki, Helsinki, Finland.
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3
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Dejanovic B, Sheng M, Hanson JE. Targeting synapse function and loss for treatment of neurodegenerative diseases. Nat Rev Drug Discov 2024; 23:23-42. [PMID: 38012296 DOI: 10.1038/s41573-023-00823-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2023] [Indexed: 11/29/2023]
Abstract
Synapse dysfunction and loss are hallmarks of neurodegenerative diseases that correlate with cognitive decline. However, the mechanisms and therapeutic strategies to prevent or reverse synaptic damage remain elusive. In this Review, we discuss recent advances in understanding the molecular and cellular pathways that impair synapses in neurodegenerative diseases, including the effects of protein aggregation and neuroinflammation. We also highlight emerging therapeutic approaches that aim to restore synaptic function and integrity, such as enhancing synaptic plasticity, preventing synaptotoxicity, modulating neuronal network activity and targeting immune signalling. We discuss the preclinical and clinical evidence for each strategy, as well as the challenges and opportunities for developing effective synapse-targeting therapeutics for neurodegenerative diseases.
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Affiliation(s)
| | - Morgan Sheng
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jesse E Hanson
- Department of Neuroscience, Genentech, South San Francisco, CA, USA.
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Zagrebelsky M, Korte M. Are TrkB receptor agonists the right tool to fulfill the promises for a therapeutic value of the brain-derived neurotrophic factor? Neural Regen Res 2024; 19:29-34. [PMID: 37488840 PMCID: PMC10479861 DOI: 10.4103/1673-5374.374138] [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: 12/06/2022] [Revised: 02/20/2023] [Accepted: 03/27/2023] [Indexed: 07/26/2023] Open
Abstract
Brain-derived neurotrophic factor signaling via its receptor tropomyosin receptor kinase B regulates several crucial physiological processes. It has been shown to act in the brain, promoting neuronal survival, growth, and plasticity as well as in the rest of the body where it is involved in regulating for instance aspects of the metabolism. Due to its crucial and very pleiotropic activity, reduction of brain-derived neurotrophic factor levels and alterations in the brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling have been found to be associated with a wide spectrum of neurological diseases. However, because of its poor bioavailability and pharmacological properties, brain-derived neurotrophic factor itself has a very low therapeutic value. Moreover, the concomitant binding of exogenous brain-derived neurotrophic factor to the p75 neurotrophin receptor has the potential to elicit several unwanted and deleterious side effects. Therefore, developing tools and approaches to specifically promote tropomyosin receptor kinase B signaling has become an important goal of translational research. Among the newly developed tools are different categories of tropomyosin receptor kinase B receptor agonist molecules. In this review, we give a comprehensive description of the different tropomyosin receptor kinase B receptor agonist drugs developed so far and of the results of their application in animal models of several neurological diseases. Moreover, we discuss the main benefits of tropomyosin receptor kinase B receptor agonists, concentrating especially on the new tropomyosin receptor kinase B agonist antibodies. The benefits observed both in vitro and in vivo upon application of tropomyosin receptor kinase B receptor agonist drugs seem to predominantly depend on their general neuroprotective activity and their ability to promote neuronal plasticity. Moreover, tropomyosin receptor kinase B agonist antibodies have been shown to specifically bind the tropomyosin receptor kinase B receptor and not p75 neurotrophin receptor. Therefore, while, based on the current knowledge, the tropomyosin receptor kinase B receptor agonists do not seem to have the potential to reverse the disease pathology per se, promoting brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling still has a very high therapeutic relevance.
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Affiliation(s)
- Marta Zagrebelsky
- Division of Cellular Neurobiology, Zoological Institute, TU Braunschweig, Braunschweig, Germany
| | - Martin Korte
- Division of Cellular Neurobiology, Zoological Institute, TU Braunschweig, Braunschweig, Germany
- Helmholtz Centre for Infection Research, AG NIND, Braunschweig, Germany
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5
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Roussel-Gervais A, Sgroi S, Cambet Y, Lemeille S, Seredenina T, Krause KH, Jaquet V. Genetic knockout of NTRK2 by CRISPR/Cas9 decreases neurogenesis and favors glial progenitors during differentiation of neural progenitor stem cells. Front Cell Neurosci 2023; 17:1289966. [PMID: 38161998 PMCID: PMC10757602 DOI: 10.3389/fncel.2023.1289966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/22/2023] [Indexed: 01/03/2024] Open
Abstract
The tropomyosin receptor kinase B (TrkB) is encoded by the NTRK2 gene. It belongs to the family of transmembrane tyrosine kinases, which have key roles in the development and maintenance of the nervous system. Brain-derived neurotrophic factor (BDNF) and the neurotrophins NT3 and NT4/5 have high affinity for TrkB. Dysregulation of TrkB is associated to a large spectrum of diseases including neurodegeneration, psychiatric diseases and some cancers. The function of TrkB and its role in neural development have mainly been decrypted using transgenic mouse models, pharmacological modulators and human neuronal cell lines overexpressing NTRK2. In this study, we identified high expression and robust activity of TrkB in ReNcell VM, an immortalized human neural progenitor stem cell line and generated NTRK2-deficient (NTRK2-/-) ReNcell VM using the CRISPR/Cas9 gene editing technology. Global transcriptomic analysis revealed major changes in expression of specific genes responsible for neurogenesis, neuronal development and glial differentiation. In particular, key neurogenic transcription factors were massively down-regulated in NTRK2-/- cells, while early glial progenitor markers were enriched in NTRK2-/- cells compared to NTRK2+/+. This indicates a previously undescribed inhibitory role of TrkB on glial differentiation in addition to its well-described pro-neurogenesis role. Altogether, we have generated for the first time a human neural cell line with a loss-of-function mutation of NTRK2, which represents a reproducible and readily available cell culture system to study the role of TrkB during human neural differentiation, analyze the role of TrkB isoforms as well as validate TrkB antibodies and pharmacological agents targeting the TrkB pathway.
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Affiliation(s)
- Audrey Roussel-Gervais
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Stéphanie Sgroi
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Yves Cambet
- READS Unit, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Sylvain Lemeille
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Tamara Seredenina
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Karl-Heinz Krause
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vincent Jaquet
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- READS Unit, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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6
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Ateaque S, Merkouris S, Barde YA. Neurotrophin signalling in the human nervous system. Front Mol Neurosci 2023; 16:1225373. [PMID: 37470055 PMCID: PMC10352796 DOI: 10.3389/fnmol.2023.1225373] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 06/20/2023] [Indexed: 07/21/2023] Open
Abstract
This review focuses on neurotrophins and their tyrosine kinase receptors, with an emphasis on their relevance to the function and dysfunction in the human nervous system. It also deals with measurements of BDNF levels and highlights recent findings from our laboratory on TrkB and TrkC signalling in human neurons. These include ligand selectivity and Trk activation by neurotrophins and non-neurotrophin ligands. The ligand-induced down-regulation and re-activation of Trk receptors is also discussed.
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Affiliation(s)
- Sarah Ateaque
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Spyros Merkouris
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Yves-Alain Barde
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
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7
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Yanpallewar S, Fulgenzi G, Tomassoni-Ardori F, Barrick C, Tessarollo L. Delayed onset of inherited ALS by deletion of the BDNF receptor TrkB.T1 is non-cell autonomous. Exp Neurol 2020; 337:113576. [PMID: 33359475 DOI: 10.1016/j.expneurol.2020.113576] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 12/04/2020] [Accepted: 12/21/2020] [Indexed: 12/18/2022]
Abstract
The pathophysiology of Amyotrophic Lateral Sclerosis (ALS), a disease caused by the gradual degeneration of motoneurons, is still largely unknown. Insufficient neurotrophic support has been cited as one of the causes of motoneuron cell death. Neurotrophic factors such as BDNF have been evaluated in ALS human clinical trials, but yielded disappointing results attributed to the poor pharmacokinetics and pharmacodynamics of BDNF. In the inherited ALS G93A SOD1 animal model, deletion of the BDNF receptor TrkB.T1 delays spinal cord motoneuron cell death and muscle weakness through an unknown cellular mechanism. Here we show that TrkB.T1 is expressed ubiquitously in the spinal cord and its deletion does not change the SOD1 mutant spinal cord inflammatory state suggesting that TrkB.T1 does not influence microglia or astrocyte activation. Although TrkB.T1 knockout in astrocytes preserves muscle strength and co-ordination at early stages of disease, its specific conditional deletion in motoneurons or astrocytes does not delay motoneuron cell death during the early stage of the disease. These data suggest that TrkB.T1 may limit the neuroprotective BDNF signaling to motoneurons via a non-cell autonomous mechanism providing new understanding into the reasons for past clinical failures and insights into the design of future clinical trials employing TrkB agonists in ALS.
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Affiliation(s)
| | - Gianluca Fulgenzi
- Neural Development Section, Mouse Cancer Genetics Program, CCR, NCI, NIH, USA
| | | | - Colleen Barrick
- Neural Development Section, Mouse Cancer Genetics Program, CCR, NCI, NIH, USA
| | - Lino Tessarollo
- Neural Development Section, Mouse Cancer Genetics Program, CCR, NCI, NIH, USA.
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Fan F, Tang Y, Dai H, Cao Y, Sun P, Chen Y, Chen A, Lin C. Blockade of BDNF signalling attenuates chronic visceral hypersensitivity in an IBS-like rat model. Eur J Pain 2020; 24:839-850. [PMID: 31976585 PMCID: PMC7154558 DOI: 10.1002/ejp.1534] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 12/14/2022]
Abstract
Background Irritable bowel syndrome (IBS) is a common functional disease characterized by chronic abdominal pain and changes in bowel movements. Effective therapy for visceral hypersensitivity in IBS patients remains challenging. This study investigated the roles of brain‐derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB) and the effect of ANA‐12 (a selective antagonist of TrkB) on chronic visceral hypersensitivity in an IBS‐like rat model. Methods An IBS‐like rat model was established through neonatal maternal separation (NMS), and visceral hypersensitivity was assessed by electromyographic (EMG) responses of the abdominal external oblique muscles to colorectal distention (CRD). Different doses of ANA‐12 were injected intrathecally to investigate the effect of that drug on visceral hypersensitivity, and the open field test was performed to determine whether ANA‐12 had side effects on movement. Thoracolumbar spinal BDNF, TrkB receptor and Protein kinase Mζ (PKMζ) expression were measured to investigate their roles in chronic visceral hypersensitivity. Whole‐cell recordings were made from thoracolumbar superficial dorsal horn (SDH) neurons of lamina II. Results The expression of BDNF and TrkB was enhanced in the thoracolumbar spinal cord of the NMS animals. ANA‐12 attenuated visceral hypersensitivity without side effects on motricity in NMS rats. PKMζ expression significantly decreased after the administration of ANA‐12. The frequency of spontaneous excitatory postsynaptic currents (sEPSCs) increased in the thoracolumbar SDH neurons of lamina II in NMS rats. The amplitude and frequency of sEPSCs were reduced after perfusion with ANA‐12 in NMS rats. Conclusions Neonatal maternal separation caused visceral hypersensitivity and increased synaptic activity by activating BDNF‐TrkB‐PKMζ signalling in the thoracolumbar spinal cord of adult rats. PKMζ was able to potentiate AMPA receptor (AMPAR)‐mediated sEPSCs in NMS rats. ANA‐12 attenuated visceral hypersensitivity and synaptic activity by blocking BDNF/TrkB signalling in NMS rats. Significance ANA‐12 attenuates visceral hypersensitivity via BDNF‐TrkB‐PKMζ signalling and reduces synaptic activity through AMPARs in NMS rats. This knowledge suggests that ANA‐12 could represent an interesting novel therapeutic medicine for chronic visceral hypersensitivity.
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Affiliation(s)
- Fei Fan
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China.,Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Medical University, Fuzhou, China
| | - Ying Tang
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Hengfen Dai
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China.,Affiliated Fuzhou First Hospital of Fujian Medical University, Fuzhou, China
| | - Yang Cao
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Pei Sun
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Yu Chen
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Aiqin Chen
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Chun Lin
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
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9
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Szobota S, Mathur PD, Siegel S, Black K, Saragovi HU, Foster AC. BDNF, NT-3 and Trk receptor agonist monoclonal antibodies promote neuron survival, neurite extension, and synapse restoration in rat cochlea ex vivo models relevant for hidden hearing loss. PLoS One 2019; 14:e0224022. [PMID: 31671109 PMCID: PMC6822712 DOI: 10.1371/journal.pone.0224022] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 10/03/2019] [Indexed: 12/21/2022] Open
Abstract
Neurotrophins and their mimetics are potential treatments for hearing disorders because of their trophic effects on spiral ganglion neurons (SGNs) whose connections to hair cells may be compromised in many forms of hearing loss. Studies in noise or ototoxin-exposed animals have shown that local delivery of NT-3 or BDNF has beneficial effects on SGNs and hearing. We evaluated several TrkB or TrkC monoclonal antibody agonists and small molecules, along with BDNF and NT-3, in rat cochlea ex vivo models. The TrkB agonists BDNF and a monoclonal antibody, M3, had the greatest effects on SGN survival, neurite outgrowth and branching. In organotypic cochlear explants, BDNF and M3 enhanced synapse formation between SGNs and inner hair cells and restored these connections after excitotoxin-induced synaptopathy. Loss of these synapses has recently been implicated in hidden hearing loss, a condition characterized by difficulty hearing speech in the presence of background noise. The unique profile of M3 revealed here warrants further investigation, and the broad activity profile of BDNF observed underpins its continued development as a hearing loss therapeutic.
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Affiliation(s)
- Stephanie Szobota
- Otonomy, Inc., San Diego, California, United States of America
- * E-mail:
| | | | - Sairey Siegel
- Otonomy, Inc., San Diego, California, United States of America
| | | | - H. Uri Saragovi
- Lady Davis Institute-Jewish General Hospital, McGill University, Montreal, Quebec, Canada
| | - Alan C. Foster
- Otonomy, Inc., San Diego, California, United States of America
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10
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TrkB agonistic antibodies superior to BDNF: Utility in treating motoneuron degeneration. Neurobiol Dis 2019; 132:104590. [PMID: 31470106 DOI: 10.1016/j.nbd.2019.104590] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 08/18/2019] [Accepted: 08/26/2019] [Indexed: 12/13/2022] Open
Abstract
While Brain-derived Neurotrophic Factor (BDNF) has long been implicated in treating neurological diseases, recombinant BDNF protein has failed in multiple clinical trials. In addition to its unstable and adhesive nature, BDNF can activate p75NTR, a receptor mediating cellular functions opposite to those of TrkB. We have now identified TrkB agonistic antibodies (TrkB-agoAbs) with several properties superior to BDNF: They exhibit blood half-life of days instead of hours, diffuse centimeters in neural tissues instead millimeters, and bind and activate TrkB, but not p75NTR. In addition, TrkB-agoAbs elicit much longer TrkB activation, reduced TrkB internalization and less intracellular degradation, compared with BDNF. More importantly, some of these TrkB-agoAbs bind TrkB epitopes distinct from that by BDNF, and work cooperatively with endogenous BDNF. Unlike BDNF, the TrkB-agoAbs exhibit a half-life of days/weeks and diffused readily in nerve tissues. We tested one of TrkB-agoAbs further and showed that it enhanced motoneuron survival in the spinal-root avulsion model for motoneuron degeneration in vivo. Thus, TrkB-agoAbs are promising drug candidates for the treatment of neural injury.
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11
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Han F, Guan X, Guo W, Lu B. Therapeutic potential of a TrkB agonistic antibody for ischemic brain injury. Neurobiol Dis 2019; 127:570-581. [DOI: 10.1016/j.nbd.2019.04.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/04/2019] [Accepted: 04/10/2019] [Indexed: 12/20/2022] Open
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12
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Abstract
Human induced pluripotent stem (hiPS) cell-derived neurons promise to provide better model cells for drug discovery in the context of neurodegenerative and neuropsychiatric diseases. The neuronal differentiation protocol described encompasses a cellular amplification phase for hiPS-derived neural progenitor (NP) cells. Thus, the combination of growth factor-driven expansion and inhibition of notch (GRINCH) enabled the scalable production of neurons in sufficient numbers to meet the immense material needs of a high-throughput screening (HTS) campaign. These GRINCH cells matured in 384-well microplates display neuronal markers and electrophysiological activity. The differentiation protocol was applicable to various human hiPS cell clones. In a finding and profiling campaign for modulators of the tropomyosin receptor kinase B (TrkB), the GRINCH neurons were shown to be suitable for measuring the phosphorylation and downstream signaling of the endogenously expressed TrkB. The employed techniques in the amplified luminescent proximity homogeneous assay (Alpha) and the high-throughput reverse transcription polymerase chain reaction (RT-PCR) format are transferable to other pharmaceutical drug targets. Together with the GRINCH neurons, these detection technologies open new experimental routes with tremendous potential for early drug discovery.
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Affiliation(s)
| | - Ralf Heilker
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany.
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13
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Merkouris S, Barde YA, Binley KE, Allen ND, Stepanov AV, Wu NC, Grande G, Lin CW, Li M, Nan X, Chacon-Fernandez P, DiStefano PS, Lindsay RM, Lerner RA, Xie J. Fully human agonist antibodies to TrkB using autocrine cell-based selection from a combinatorial antibody library. Proc Natl Acad Sci U S A 2018; 115:E7023-E7032. [PMID: 29987039 PMCID: PMC6065019 DOI: 10.1073/pnas.1806660115] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The diverse physiological roles of the neurotrophin family have long prompted exploration of their potential as therapeutic agents for nerve injury and neurodegenerative diseases. To date, clinical trials of one family member, brain-derived neurotrophic factor (BDNF), have disappointingly failed to meet desired endpoints. Contributing to these failures is the fact that BDNF is pharmaceutically a nonideal biologic drug candidate. It is a highly charged, yet is a net hydrophobic molecule with a low molecular weight that confers a short t1/2 in man. To circumvent these shortcomings of BDNF as a drug candidate, we have employed a function-based cellular screening assay to select activating antibodies of the BDNF receptor TrkB from a combinatorial human short-chain variable fragment antibody library. We report here the successful selection of several potent TrkB agonist antibodies and detailed biochemical and physiological characterization of one such antibody, ZEB85. By using a human TrkB reporter cell line and BDNF-responsive GABAergic neurons derived from human ES cells, we demonstrate that ZEB85 is a full agonist of TrkB, comparable in potency to BDNF toward human neurons in activation of TrkB phosphorylation, canonical signal transduction, and mRNA transcriptional regulation.
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Affiliation(s)
- Spyros Merkouris
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | - Yves-Alain Barde
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | - Kate E Binley
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | - Nicholas D Allen
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | - Alexey V Stepanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Nicholas C Wu
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
| | - Geramie Grande
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
| | - Chih-Wei Lin
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
| | - Meng Li
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | - Xinsheng Nan
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, United Kingdom
| | | | | | | | - Richard A Lerner
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037;
| | - Jia Xie
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037;
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