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Jia Y, Liu Y, Wang P, Liu Z, Zhang R, Chu M, Zhao A. NTRK2 Promotes Sheep Granulosa Cells Proliferation and Reproductive Hormone Secretion and Activates the PI3K/AKT Pathway. Animals (Basel) 2024; 14:1465. [PMID: 38791682 PMCID: PMC11117346 DOI: 10.3390/ani14101465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/04/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Neurotrophin receptor B (NTRK2), also named TRKB, belongs to the neurotrophic factor family. Previous studies have shown that NTRK2 is associated with high fertility in mammals. However, the molecular mechanism and regulatory pathway of this neurotrophic factor remain unclear. In this study, NTRK2 overexpression and NTRK2-siRNA were constructed to detect the effects of NTRK2 on the proliferation and hormone secretion of the ovarian granulosa cells (GCs) of sheep. We successfully isolated follicular phase granulosa cells in vitro from the ovaries of sheep in simultaneous estrus, and the immunofluorescence results confirmed that NTRK2 was expressed in the collected cells. Subsequently, the effect of NTRK2 on the proliferation of sheep granulosa cells was examined via cell transfection experiments. The results showed that the expression of CDK4 and CyclinD2 was significantly increased after NTRK2 overexpression, while the opposite trend was observed after the inhibition of NTRK2 expression (p < 0.05). The EdU and CCK-8 assays showed that the proliferation rate of sheep GCs was significantly increased after NTRK2 overexpression, while the opposite trend was observed after the inhibition of NTRK2 expression (p < 0.05). Moreover, NTRK2 significantly increased the expression of steroidogenesis-related genes, including steroidogenic acute regulatory protein (STAR) and hydroxy-δ-5-steroid dehydrogenase (HSD3B1), and cytochrome P450 family 19 subfamily A member 1 (CYP19A1). The ELISA results showed that the secretion levels of E2 and P4 significantly increased after NTRK2 overexpression, while the opposite trend was observed after the inhibition of NTRK2 expression (p < 0.05). Previous studies had confirmed that NTRK2 gene belongs to the PI3K-AKT signaling pathway and participates in the signaling of this pathway. This was demonstrated by protein-protein interaction analysis and NTRK2 belongs to the PI3K-AKT pathway. The modification of PI3K and AKT, markers of the PI3K-AKT pathway, via phosphorylation was increased after NTRK2 overexpression in the sheep GCs, while the opposite trend was observed after the inhibition of NTRK2 expression (p < 0.05). Overall, these results suggest that the NTRK2 gene regulates the proliferation of GCs and the secretion of steroid hormones in sheep, and that it influences the phosphorylation level of the PI3K/AKT signaling pathway. These findings provided a theoretical basis and new perspectives for exploring the regulation of NTRK2 gene in the development of ovine follicles.
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Affiliation(s)
- Yuhang Jia
- College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Hangzhou 311300, China;
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Yufang Liu
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Peng Wang
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Ziyi Liu
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Runan Zhang
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Mingxing Chu
- State Key Laboratory of Animal Biotech Breeding, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (Y.L.); (P.W.); (Z.L.); (R.Z.)
| | - Ayong Zhao
- College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Hangzhou 311300, China;
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2
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Stepanova OV, Fursa GA, Karsuntseva EK, Andretsova SS, Chadin AV, Voronova AD, Shishkina VS, Semkina AS, Reshetov IV, Chekhonin VP. Features of Remyelination after Transplantation of Olfactory Ensheathing Cells with Neurotrophic Factors into Spinal Cord Cysts. Bull Exp Biol Med 2024; 176:666-671. [PMID: 38727956 DOI: 10.1007/s10517-024-06088-x] [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: 12/05/2022] [Indexed: 05/18/2024]
Abstract
This paper shows for the first time that co-transplantation of human olfactory ensheathing cells with neurotrophin-3 into spinal cord cysts is more effective for activation of remyelination than transplantation of cells with brain-derived neurotrophic factor and a combination of these two factors. The studied neurotrophic factors do not affect proliferation and migration of ensheathing cells in vitro. It can be concluded that the maximum improvement of motor function in rats receiving ensheathing cells with neurotrophin-3 is largely determined by activation of remyelination.
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Affiliation(s)
- O V Stepanova
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
- E. I. Chazov National Medical Research Center of Cardiology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - G A Fursa
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - E K Karsuntseva
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia.
| | - S S Andretsova
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
- M. V. Lomonosov Moscow State University, Moscow, Russia
| | - A V Chadin
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - A D Voronova
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - V S Shishkina
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - A S Semkina
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
- Pirogov Russian National Research Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - I V Reshetov
- University Clinical Hospital, I. M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation (Sechenov University), Moscow, Russia
| | - V P Chekhonin
- V. P. Serbsky National Medical Research Centre of Psychiatry and Narcology, Ministry of Health of the Russian Federation, Moscow, Russia
- Pirogov Russian National Research Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
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3
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Kim J, He MJ, Widmann AK, Lee FS. The role of neurotrophic factors in novel, rapid psychiatric treatments. Neuropsychopharmacology 2024; 49:227-245. [PMID: 37673965 PMCID: PMC10700398 DOI: 10.1038/s41386-023-01717-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 07/11/2023] [Accepted: 07/26/2023] [Indexed: 09/08/2023]
Abstract
Neurotrophic factors are a family of growth factors that modulate cellular growth, survival, and differentiation. For many decades, it has been generally believed that a lack of neurotrophic support led to the decreased neuronal synaptic plasticity, death, and loss of non-neuronal supportive cells seen in neuropsychiatric disorders. Traditional psychiatric medications that lead to immediate increases in neurotransmitter levels at the synapse have been shown also to elevate synaptic neurotrophic levels over weeks, correlating with the time course of the therapeutic effects of these drugs. Recent advances in psychiatric treatments, such as ketamine and psychedelics, have shown a much faster onset of therapeutic effects (within minutes to hours). They have also been shown to lead to a rapid release of neurotrophins into the synapse. This has spurred a significant shift in understanding the role of neurotrophins and how the receptor tyrosine kinases that bind neurotrophins may work in concert with other signaling systems. In this review, this renewed understanding of synaptic receptor signaling interactions and the clinical implications of this mechanistic insight will be discussed within the larger context of the well-established roles of neurotrophic factors in psychiatric disorders and treatments.
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Affiliation(s)
- Jihye Kim
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Michelle J He
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Alina K Widmann
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Francis S Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, 10065, USA.
- Department of Pharmacology, Weill Cornell Medicine, New York, NY, 10065, USA.
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4
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Danelon V, Garret-Thomson SC, Almo SC, Lee FS, Hempstead BL. Immune activation of the p75 neurotrophin receptor: implications in neuroinflammation. Front Mol Neurosci 2023; 16:1305574. [PMID: 38106879 PMCID: PMC10722190 DOI: 10.3389/fnmol.2023.1305574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/10/2023] [Indexed: 12/19/2023] Open
Abstract
Despite structural similarity with other tumor necrosis factor receptor superfamily (TNFRSF) members, the p75 neurotrophin receptor (p75NTR, TNFR16) mediates pleiotropic biological functions not shared with other TNFRs. The high level of p75NTR expression in the nervous system instead of immune cells, its utilization of co-receptors, and its interaction with soluble dimeric, rather than soluble or cell-tethered trimeric ligands are all characteristics which distinguish it from most other TNFRs. Here, we compare these attributes to other members of the TNFR superfamily. In addition, we describe the recent evolutionary adaptation in B7-1 (CD80), an immunoglobulin (Ig) superfamily member, which allows engagement to neuronally-expressed p75NTR. B7-1-mediated binding to p75NTR occurs in humans and other primates, but not lower mammals due to specific sequence changes that evolved recently in primate B7-1. This discovery highlights an additional mechanism by which p75NTR can respond to inflammatory cues and trigger synaptic elimination in the brain through engagement of B7-1, which was considered to be immune-restricted. These observations suggest p75NTR does share commonality with other immune co-modulatory TNFR family members, by responding to immunoregulatory cues. The evolution of primate B7-1 to bind and elicit p75NTR-mediated effects on neuronal morphology and function are discussed in relationship to immune-driven modulation of synaptic actions during injury or inflammation.
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Affiliation(s)
- Victor Danelon
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, NY, United States
| | | | - Steven C. Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, United States
| | - Barbara L. Hempstead
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, NY, United States
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5
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Morano NC, Smith RS, Danelon V, Schreiner R, Patel U, Herrera NG, Smith C, Olson SM, Laerke MK, Celikgil A, Garforth SJ, Garrett-Thomson SC, Lee FS, Hempstead BL, Almo SC. Human immunomodulatory ligand B7-1 mediates synaptic remodeling via the p75 neurotrophin receptor. J Clin Invest 2022; 132:e157002. [PMID: 36107635 PMCID: PMC9663165 DOI: 10.1172/jci157002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 09/13/2022] [Indexed: 12/30/2023] Open
Abstract
Cell surface receptors, ligands, and adhesion molecules underlie development, circuit formation, and synaptic function of the central nervous system and represent important therapeutic targets for many neuropathologies. The functional contributions of interactions between cell surface proteins of neurons and nonneuronal cells have not been fully addressed. Using an unbiased protein-protein interaction screen, we showed that the human immunomodulatory ligand B7-1 (hB7-1) interacts with the p75 neurotrophin receptor (p75NTR) and that the B7-1:p75NTR interaction is a recent evolutionary adaptation present in humans and other primates, but absent in mice, rats, and other lower mammals. The surface of hB7-1 that engages p75NTR overlaps with the hB7-1 surface involved in CTLA-4/CD28 recognition, and these molecules directly compete for binding to p75NTR. Soluble or membrane-bound hB7-1 altered dendritic morphology of cultured hippocampal neurons, with loss of the postsynaptic protein PSD95 in a p75NTR-dependent manner. Abatacept, an FDA-approved therapeutic (CTLA-4-hFc fusion) inhibited these processes. In vivo injection of hB7-1 into the murine subiculum, a hippocampal region affected in Alzheimer's disease, resulted in p75NTR-dependent pruning of dendritic spines. Here, we report the biochemical interaction between B7-1 and p75NTR, describe biological effects on neuronal morphology, and identify a therapeutic opportunity for treatment of neuroinflammatory diseases.
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Affiliation(s)
- Nicholas C. Morano
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, New York, USA
| | - Roshelle S. Smith
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, New York, New York, USA
| | - Victor Danelon
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, New York, New York, USA
| | - Ryan Schreiner
- Division of Regenerative Medicine, Hartman Institute for Therapeutic Organ Regeneration, Ansary Stem Cell Institute, Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Uttsav Patel
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
| | - Natalia G. Herrera
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
| | - Carla Smith
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
| | - Steven M. Olson
- Department of Computer Science, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Michelle K. Laerke
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, New York, New York, USA
| | - Alev Celikgil
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
| | - Scott J. Garforth
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
| | | | - Francis S. Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, New York, USA
| | - Barbara L. Hempstead
- Department of Medicine, Weill Cornell Graduate School of Medical Sciences, New York, New York, USA
| | - Steven C. Almo
- Department of Biochemistry, Albert Einstein College of Medicine, New York, New York, USA
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6
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A, B, C's of Trk Receptors and Their Ligands in Ocular Repair. Int J Mol Sci 2022; 23:ijms232214069. [PMID: 36430547 PMCID: PMC9695972 DOI: 10.3390/ijms232214069] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/29/2022] [Accepted: 11/06/2022] [Indexed: 11/16/2022] Open
Abstract
Neurotrophins are a family of closely related secreted proteins that promote differentiation, development, and survival of neurons, which include nerve growth factor (NGF), brain-derived neurotrophic factor, neurotrophin-3, and neurotrophin-4. All neurotrophins signal through tropomyosin receptor kinases (TrkA, TrkB, and TrkC) which are more selective to NGF, brain-derived neurotrophic factor, and neurotrophin-3, respectively. NGF is the most studied neurotrophin in the ocular surface and a human recombinant NGF has reached clinics, having been approved to treat neurotrophic keratitis. Brain-derived neurotrophic factor, neurotrophin-3, and neurotrophin-4 are less studied neurotrophins in the ocular surface, even though brain-derived neurotrophic factor is well characterized in glaucoma, retina, and neuroscience. Recently, neurotrophin analogs with panTrk activity and TrkC selectivity have shown promise as novel drugs for treating dry eye disease. In this review, we discuss the biology of the neurotrophin family, its role in corneal homeostasis, and its use in treating ocular surface diseases. There is an unmet need to investigate parenteral neurotrophins and its analogs that activate TrkB and TrkC selectively.
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7
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Conroy JN, Coulson EJ. High-affinity TrkA and p75 neurotrophin receptor complexes: A twisted affair. J Biol Chem 2022; 298:101568. [PMID: 35051416 PMCID: PMC8889134 DOI: 10.1016/j.jbc.2022.101568] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 10/27/2022] Open
Abstract
Neurotrophin signaling is essential for normal nervous system development and adult function. Neurotrophins are secreted proteins that signal via interacting with two neurotrophin receptor types: the multifaceted p75 neurotrophin receptor and the tropomyosin receptor kinase receptors. In vivo, neurons compete for the limited quantities of neurotrophins, a process that underpins neural plasticity, axonal targeting, and ultimately survival of the neuron. Thirty years ago, it was discovered that p75 neurotrophin receptor and tropomyosin receptor kinase A form a complex and mediate high-affinity ligand binding and survival signaling; however, despite decades of functional and structural research, the mechanism of modulation that yields this high-affinity complex remains unclear. Understanding the structure and mechanism of high-affinity receptor generation will allow development of pharmaceuticals to modulate this function for treatment of the many nervous system disorders in which altered neurotrophin expression or signaling plays a causative or contributory role. Here we re-examine the key older literature and integrate it with more recent studies on the topic of how these two receptors interact. We also identify key outstanding questions and propose a model of inside-out allosteric modulation to assist in resolving the elusive high-affinity mechanism and complex.
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Affiliation(s)
- Jacinta N Conroy
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Elizabeth J Coulson
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia; Clem Jones Centre for Ageing and Disease Research, The University of Queensland, Brisbane, Queensland, Australia.
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8
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Sung K, Ferrari LF, Yang W, Chung C, Zhao X, Gu Y, Lin S, Zhang K, Cui B, Pearn ML, Maloney MT, Mobley WC, Levine JD, Wu C. Swedish Nerve Growth Factor Mutation (NGF R100W) Defines a Role for TrkA and p75 NTR in Nociception. J Neurosci 2018; 38:3394-3413. [PMID: 29483280 PMCID: PMC5895035 DOI: 10.1523/jneurosci.1686-17.2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 01/23/2018] [Accepted: 02/12/2018] [Indexed: 12/14/2022] Open
Abstract
Nerve growth factor (NGF) exerts multiple functions on target neurons throughout development. The recent discovery of a point mutation leading to a change from arginine to tryptophan at residue 100 in the mature NGFβ sequence (NGFR100W) in patients with hereditary sensory and autonomic neuropathy type V (HSAN V) made it possible to distinguish the signaling mechanisms that lead to two functionally different outcomes of NGF: trophic versus nociceptive. We performed extensive biochemical, cellular, and live-imaging experiments to examine the binding and signaling properties of NGFR100W Our results show that, similar to the wild-type NGF (wtNGF), the naturally occurring NGFR100W mutant was capable of binding to and activating the TrkA receptor and its downstream signaling pathways to support neuronal survival and differentiation. However, NGFR100W failed to bind and stimulate the 75 kDa neurotrophic factor receptor (p75NTR)-mediated signaling cascades (i.e., the RhoA-Cofilin pathway). Intraplantar injection of NGFR100W into adult rats induced neither TrkA-mediated thermal nor mechanical acute hyperalgesia, but retained the ability to induce chronic hyperalgesia based on agonism for TrkA signaling. Together, our studies provide evidence that NGFR100W retains trophic support capability through TrkA and one aspect of its nociceptive signaling, but fails to engage p75NTR signaling pathways. Our findings suggest that wtNGF acts via TrkA to regulate the delayed priming of nociceptive responses. The integration of both TrkA and p75NTR signaling thus appears to regulate neuroplastic effects of NGF in peripheral nociception.SIGNIFICANCE STATEMENT In the present study, we characterized the naturally occurring nerve growth factor NGFR100W mutant that is associated with hereditary sensory and autonomic neuropathy type V. We have demonstrated for the first time that NGFR100W retains trophic support capability through TrkA, but fails to engage p75NTR signaling pathways. Furthermore, after intraplantar injection into adult rats, NGFR100W induced neither thermal nor mechanical acute hyperalgesia, but retained the ability to induce chronic hyperalgesia. We have also provided evidence that the integration of both TrkA- and p75NTR-mediated signaling appears to regulate neuroplastic effects of NGF in peripheral nociception. Our study with NGFR100W suggests that it is possible to uncouple trophic effect from nociceptive function, both induced by wild-type NGF.
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Affiliation(s)
| | - Luiz F Ferrari
- Department of Oral Surgery, University of California San Francisco, San Francisco, California 94143
| | - Wanlin Yang
- Department of Neurosciences
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China 200025
| | - ChiHye Chung
- Department of Biological Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143-701, South Korea
| | | | - Yingli Gu
- Department of Neurosciences
- Department of Neurology, the Fourth Hospital of Harbin Medical University, Harbin, Heilongjiang, China 150001
| | - Suzhen Lin
- Department of Neurosciences
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China 200025
| | - Kai Zhang
- Department of Chemistry
- Department of Biochemistry, Neuroscience Program, Center for Biophysics and Quantitative Biology, Chemistry-Biology Interface Training Program, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, and
| | | | - Matthew L Pearn
- Department of Anesthesiology, University of California San Diego, School of Medicine, La Jolla, California 92093
- V.A. San Diego Healthcare System, San Diego, California 92161
| | - Michael T Maloney
- Department of Neurosciences, Stanford University, Stanford, California 94305
| | | | - Jon D Levine
- Department of Oral Surgery, University of California San Francisco, San Francisco, California 94143
| | - Chengbiao Wu
- Department of Neurosciences,
- V.A. San Diego Healthcare System, San Diego, California 92161
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9
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Targeting Neurotrophins to Specific Populations of Neurons: NGF, BDNF, and NT-3 and Their Relevance for Treatment of Spinal Cord Injury. Int J Mol Sci 2017; 18:ijms18030548. [PMID: 28273811 PMCID: PMC5372564 DOI: 10.3390/ijms18030548] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 01/01/2023] Open
Abstract
Neurotrophins are a family of proteins that regulate neuronal survival, synaptic function, and neurotransmitter release, and elicit the plasticity and growth of axons within the adult central and peripheral nervous system. Since the 1950s, these factors have been extensively studied in traumatic injury models. Here we review several members of the classical family of neurotrophins, the receptors they bind to, and their contribution to axonal regeneration and sprouting of sensory and motor pathways after spinal cord injury (SCI). We focus on nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3), and their effects on populations of neurons within diverse spinal tracts. Understanding the cellular targets of neurotrophins and the responsiveness of specific neuronal populations will allow for the most efficient treatment strategies in the injured spinal cord.
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10
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Vignoli B, Battistini G, Melani R, Blum R, Santi S, Berardi N, Canossa M. Peri-Synaptic Glia Recycles Brain-Derived Neurotrophic Factor for LTP Stabilization and Memory Retention. Neuron 2016; 92:873-887. [PMID: 27746130 DOI: 10.1016/j.neuron.2016.09.031] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 07/24/2016] [Accepted: 09/08/2016] [Indexed: 10/20/2022]
Abstract
Glial cells respond to neuronal activation and release neuroactive molecules (termed "gliotransmitters") that can affect synaptic activity and modulate plasticity. In this study, we used molecular genetic tools, ultra-structural microscopy, and electrophysiology to assess the role of brain-derived neurotrophic factor (BDNF) on cortical gliotransmission in vivo. We find that glial cells recycle BDNF that was previously secreted by neurons as pro-neurotrophin following long-term potentiation (LTP)-inducing electrical stimulation. Upon BDNF glial recycling, we observed tight, temporal, highly localized TrkB phosphorylation on adjacent neurons, a process required to sustain LTP. Engagement of BDNF recycling by astrocytes represents a novel mechanism by which cortical synapses can expand BDNF action and provide synaptic changes that are relevant for the acquisition of new memories. Accordingly, mice deficient in BDNF glial recycling fail to recognize familiar from novel objects, indicating a physiological requirement for this process in memory consolidation.
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Affiliation(s)
- Beatrice Vignoli
- European Brain Research Institute (EBRI) "Rita Levi-Montalcini", via del Fosso di Fiorano 64, 00143 Rome, Italy; Centre for Integrative Biology (CIBIO), University of Trento, via Sommarive 9, 38123 Povo (TN), Italy.
| | - Giulia Battistini
- Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, via San Donato 15, 40127 Bologna, Italy
| | - Riccardo Melani
- National Research Council (CNR), Institute of Neuroscience, via Moruzzi 1, 56100 Pisa, Italy
| | - Robert Blum
- Institute for Clinical Neurobiology, University Hospital, Julius Maximilians University, Versbacher Straße 5, 97078 Würzburg, Germany
| | - Spartaco Santi
- National Research Council (CNR), Institute of Molecular Genetics (IGM), Laboratory of Muscoloskeletal Cell Biology, IOR, via di Barbiano1/10, 40136 Bologna, Italy
| | - Nicoletta Berardi
- National Research Council (CNR), Institute of Neuroscience, via Moruzzi 1, 56100 Pisa, Italy; Department of Neuroscience, Psychology, Drug Research, and Child Health (NEUROFARBA), University of Florence, via di San Salvi 26, 50100 Florence, Italy
| | - Marco Canossa
- European Brain Research Institute (EBRI) "Rita Levi-Montalcini", via del Fosso di Fiorano 64, 00143 Rome, Italy; Centre for Integrative Biology (CIBIO), University of Trento, via Sommarive 9, 38123 Povo (TN), Italy.
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11
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Norman BH, McDermott JS. Targeting the Nerve Growth Factor (NGF) Pathway in Drug Discovery. Potential Applications to New Therapies for Chronic Pain. J Med Chem 2016; 60:66-88. [DOI: 10.1021/acs.jmedchem.6b00964] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Bryan H. Norman
- Discovery Chemistry
Research and Technologies and ‡Neurophysiology, Lilly Research Laboratories, A Division of Eli Lilly and Company, Indianapolis, Lilly
Corporate Center, Indiana 46285, United States
| | - Jeff S. McDermott
- Discovery Chemistry
Research and Technologies and ‡Neurophysiology, Lilly Research Laboratories, A Division of Eli Lilly and Company, Indianapolis, Lilly
Corporate Center, Indiana 46285, United States
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12
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Overexpression of NTRK1 Promotes Differentiation of Neural Stem Cells into Cholinergic Neurons. BIOMED RESEARCH INTERNATIONAL 2015; 2015:857202. [PMID: 26509167 PMCID: PMC4609807 DOI: 10.1155/2015/857202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/25/2015] [Accepted: 09/16/2015] [Indexed: 11/17/2022]
Abstract
Neurotrophic tyrosine kinase type 1 (NTRK1) plays critical roles in proliferation, differentiation, and survival of cholinergic neurons; however, it remains unknown whether enhanced expression of NTRK1 in neural stem cells (NSCs) can promote their differentiation into mature neurons. In this study, a plasmid encoding the rat NTRK1 gene was constructed and transfected into C17.2 mouse neural stem cells (NSCs). NTRK1 overexpression in C17.2 cells was confirmed by western blot. The NSCs overexpressing NTRK1 and the C17.2 NSCs transfected by an empty plasmid vector were treated with or without 100 ng/mL nerve growth factor (NGF) for 7 days. Expression of the cholinergic cell marker, choline acetyltransferase (ChAT), was detected by florescent immunocytochemistry (ICC). In the presence of NGF induction, the NSCs overexpressing NTRK1 differentiated into ChAT-immunopositive cells at 3-fold higher than the NSCs transfected by the plasmid vector (26% versus 9%, P < 0.05). The data suggest that elevated NTRK1 expression increases differentiation of NSCs into cholinergic neurons under stimulation of NGF. The approach also represents an efficient strategy for generation of cholinergic neurons.
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Covaceuszach S, Konarev PV, Cassetta A, Paoletti F, Svergun DI, Lamba D, Cattaneo A. The conundrum of the high-affinity NGF binding site formation unveiled? Biophys J 2015; 108:687-97. [PMID: 25650935 PMCID: PMC4317559 DOI: 10.1016/j.bpj.2014.11.3485] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 11/05/2014] [Accepted: 11/07/2014] [Indexed: 11/15/2022] Open
Abstract
The homodimer NGF (nerve growth factor) exerts its neuronal activity upon binding to either or both distinct transmembrane receptors TrkA and p75(NTR). Functionally relevant interactions between NGF and these receptors have been proposed, on the basis of binding and signaling experiments. Namely, a ternary TrkA/NGF/p75(NTR) complex is assumed to be crucial for the formation of the so-called high-affinity NGF binding sites. However, the existence, on the cell surface, of direct extracellular interactions is still a matter of controversy. Here, supported by a small-angle x-ray scattering solution study of human NGF, we propose that it is the oligomerization state of the secreted NGF that may drive the formation of the ternary heterocomplex. Our data demonstrate the occurrence in solution of a concentration-dependent distribution of dimers and dimer of dimers. A head-to-head molecular assembly configuration of the NGF dimer of dimers has been validated. Overall, these findings prompted us to suggest a new, to our knowledge, model for the transient ternary heterocomplex, i.e., a TrkA/NGF/p75(NTR) ligand/receptors molecular assembly with a (2:4:2) stoichiometry. This model would neatly solve the problem posed by the unconventional orientation of p75(NTR) with respect to TrkA, as being found in the crystal structures of the TrkA/NGF and p75(NTR)/NGF complexes.
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Affiliation(s)
- Sonia Covaceuszach
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy
| | - Petr V Konarev
- European Molecular Biology Laboratory, Hamburg Outstation, Hamburg, Germany; Institute of Crystallography, Russian Academy of Sciences, Moscow, Russia
| | - Alberto Cassetta
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy
| | | | - Dmitri I Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, Hamburg, Germany
| | - Doriano Lamba
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Trieste, Italy.
| | - Antonino Cattaneo
- European Brain Research Institute, Roma, Italy; Scuola Normale Superiore, Pisa, Italy.
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ROY MADHUMITA, TAPADIA MADHUG, JOSHI SHOBHNA, KOCH BIPLOB. Molecular and genetic basis of depression. J Genet 2015; 93:879-92. [DOI: 10.1007/s12041-014-0449-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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15
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Dedoni S, Olianas MC, Ingianni A, Onali P. Type I interferons up-regulate the expression and signalling of p75 NTR/TrkA receptor complex in differentiated human SH-SY5Y neuroblastoma cells. Neuropharmacology 2014; 79:321-34. [PMID: 24333329 DOI: 10.1016/j.neuropharm.2013.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 10/25/2013] [Accepted: 12/02/2013] [Indexed: 01/10/2023]
Abstract
Both type I interferons (IFNs) and neurotrophins regulate neuroadaptive responses, but relatively little is known on the interaction between these two classes of regulatory proteins. Here we investigated the effect of IFN-β on the expression and functional activity of the common neurotrophin receptor p75NTR and the nerve growth factor (NGF) receptor TrkA. In differentiated human SH-SY5Y neuroblastoma cells prolonged exposure to IFN-β up-regulated p75NTR and TrkA levels, failed to affect the content of sortilin, a p75NTR co-receptor, and, consistent with our previous finding, down-regulated the brain-derived neurotrophic factor receptor TrkB. Quantitative real time RT-PCR indicated that IFN-β increased p75NTR and TrkA mRNA levels. In control and IFN-β treated cells proNGF failed to induce c-Jun N-terminal kinase and nuclear factor/kB activation, two p75NTR/sortilin signalling pathways mediating neuronal death. On the other hand, IFN-β treatment enhanced TrkA autophosphorylation and signalling induced by NGF and proNGF. Knockdown of p75NTR by siRNA reduced TrkA activation by proNGF and a subnanomolar concentration of NGF, whereas co-immunoprecipitation indicated close association of p75NTR and TrkA. Co-treatment with either NGF or proNGF reduced IFN-β pro-apoptotic and anti-neurotrophic effects. Similarly, in primary mouse hippocampal neurons IFN-β increased p75NTR and TrkA expression, down-regulated TrkB and enhanced NGF-induced phosphorylation of the pro-survival protein kinase Akt. The data demonstrate that in neuronal cells IFN-β differentially affects the expression and signalling of neurotrophin receptors and suggest that the up-regulation of the p75NTR/TrkA signalling complex may constitute a novel mechanism by which this cytokine selectively attenuates its pro-apoptotic effect in NGF-responsive cells.
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Affiliation(s)
- Simona Dedoni
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, and Section of Applied Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Maria C Olianas
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, and Section of Applied Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Angela Ingianni
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, and Section of Applied Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Pierluigi Onali
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, and Section of Applied Microbiology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.
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16
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Akiyama Y, Mikami Y, Watanabe E, Watanabe N, Toriumi T, Takahashi T, Komiyama K, Isokawa K, Shimizu N, Honda MJ. The P75 neurotrophin receptor regulates proliferation of the human MG63 osteoblast cell line. Differentiation 2014; 87:111-8. [PMID: 24582280 DOI: 10.1016/j.diff.2014.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 01/17/2014] [Indexed: 02/07/2023]
Abstract
The 75 kDa transmembrane protein, p75(NTR), is a marker of mesenchymal stem cells (MSCs). Isolated MSCs are capable of differentiating into osteoblasts, but the molecular function of p75(NTR) in MSCs and osteoblasts is poorly understood. The aim of this study was to examine the function of p75(NTR) in the human MG63 osteoblast cell line compared to the murine MC3T3E-1 pre-osteoblast cell line. MG63 cells and MC3T3-E1 cells expressing exogenous p75(NTR) protein (denoted as p75-MG63 and p75GFP-E1, respectively) were generated to compare osteogenic differentiation and cell proliferation abilities. Overexpression of p75(NTR) induced alkaline phosphatase activity and the mRNA expression of osteoblast-related genes such as osterix and bone sialoprotein in both p75-MG63 and p75GFP-E1. Interestingly, exogenous p75(NTR) stimulated cell proliferation and cell cycle progression in p75GFP-E1, but not in p75-MG63. To elucidate any different effects of p75(NTR) expression on osteogenic differentiation and cell proliferation, we examined the mRNA expression of tropomyosin receptor kinase (trk) genes (trkA, trkB, trkC) and Nogo receptor (NgR), which are binding partners of p75(NTR). Although trkA, trkB, and trkC were detected in both p75-MG63 and p75GFP-E1, only NgR was detected in p75-MG63. We then used the K252a inhibitor of the trks to identify the signaling pathway for osteogenic differentiation and cell proliferation. Inhibition of trks by K252a suppressed p75(NTR)-mediated osteogenic differentiation of p75GFP-E1, whereas deletion of the GDI domain in P75(NTR) from the p75-MG63 produced enhanced cell proliferation compared to p75-MG63. These results suggest that p75(NTR) signaling associated with trk receptors promotes both cell proliferation and osteoblast differentiation, but that p75(NTR)-mediated proliferation may be suppressed by signaling from the p75(NTR)/NgR complex.
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Affiliation(s)
- Yuko Akiyama
- Nihon University Graduate School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Yoshikazu Mikami
- Department of Pathology, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Eri Watanabe
- Laboratory of Diagnostic Medicine, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Nobukazu Watanabe
- Laboratory of Diagnostic Medicine, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Taku Toriumi
- Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Tomihisa Takahashi
- Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Kazuo Komiyama
- Department of Pathology, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Keitaro Isokawa
- Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Noriyoshi Shimizu
- Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Orthodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Masaki J Honda
- Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
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17
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Nadeau JR, Wilson-Gerwing TD, Verge VMK. Induction of a reactive state in perineuronal satellite glial cells akin to that produced by nerve injury is linked to the level of p75NTR expression in adult sensory neurons. Glia 2014; 62:763-77. [PMID: 24616056 DOI: 10.1002/glia.22640] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 01/16/2014] [Indexed: 12/19/2022]
Abstract
Satellite glial cells (SGCs) surrounding primary sensory neurons are similar to astrocytes of the central nervous system in that they buffer the extracellular environment via potassium and calcium channels and express the intermediate filament glial fibrillary acidic protein (GFAP). Peripheral nerve injury induces a reactive state in SGCs that includes SGC proliferation, increased SGC/SGC coupling via gap junctions, decreased inward rectifying potassium channel 4.1 (Kir 4.1) expression and increased expression of GFAP and the common neurotrophin receptor, p75NTR. In contrast, neuronal p75NTR expression, normally detected in ∼80% of adult rat sensory neurons, decreases in response to peripheral axotomy. Given the differential regulation of p75NTR expression in neurons versus SGCs with injury, we hypothesized that reduced signaling via neuronal p75NTR contributes to the induction of a reactive state in SGCs. We found that reducing neuronal p75NTR protein expression in uninjured sensory neurons by intrathecal subarachnoid infusion of p75NTR-selective anti-sense oligodeoxynucleotides for one week was sufficient to induce a "reactive-like" state in the perineuronal SGCs akin to that normally observed following peripheral nerve injury. This reactive state included significantly increased SGC p75NTR, GFAP and gap junction protein connexin-43 protein expression, increased numbers of SGCs surrounding individual sensory neurons and decreased SGC Kir 4.1 channel expression. Collectively, this supports the tenet that reductions in target-derived trophic support leading to, or as a consequence of, reduced neuronal p75NTR expression plays a critical role in switching the SGC to a reactive state.
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Affiliation(s)
- Joelle R Nadeau
- Department of Anatomy and Cell Biology, University of Saskatchewan/Cameco MS Neuroscience Research Center, Saskatoon City Hospital, Saskatoon, SK, Canada
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18
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Verge VMK, Andreassen CS, Arnason TG, Andersen H. Mechanisms of disease: role of neurotrophins in diabetes and diabetic neuropathy. HANDBOOK OF CLINICAL NEUROLOGY 2014; 126:443-60. [PMID: 25410238 DOI: 10.1016/b978-0-444-53480-4.00032-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Neuropathy is an insidious and devastating consequence of diabetes. Early studies provided a strong rationale for deficient neurotrophin support in the pathogenesis of diabetic neuropathy in a number of critical tissues and organs. It has now been over a decade since the first failed human neurotrophin supplementation clinical trials, but mounting evidence still implicates these trophic factors in diabetic neuropathy. Since then, tremendous advances have been made in our understanding of the complexities of neurotrophin signaling and processing and how the diabetic milieu might impact this. This in turn changes both our perception of how the altered trophic environment contributes to the etiology of diabetic neuropathy and the design of future neurotrophin therapeutic interventions. This chapter summarizes some of these findings and attempts to integrate neurotrophin actions on the nervous system with an increasing appreciation of their role in the regulation of metabolic processes in diabetes that impact the diabetic neuropathic state.
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Affiliation(s)
- Valerie M K Verge
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Canada; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon City Hospital, Saskatoon, Canada.
| | - Christer S Andreassen
- Department of Otorhinolaryngology and Head and Neck Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Terra G Arnason
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Canada; Department of Medicine, Division of Endocrinology and Metabolism, University of Saskatchewan, Saskatoon, Canada
| | - Henning Andersen
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
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19
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Zanin JP, Battiato NL, Rovasio RA. Neurotrophic factor NT-3 displays a non-canonical cell guidance signaling function for cephalic neural crest cells. Eur J Cell Biol 2013; 92:264-79. [PMID: 24252516 DOI: 10.1016/j.ejcb.2013.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/08/2013] [Accepted: 10/13/2013] [Indexed: 12/30/2022] Open
Abstract
Chemotactic cell migration is triggered by extracellular concentration gradients of molecules segregated by target fields. Neural crest cells (NCCs), paradigmatic as an accurately moving cell population, undergo wide dispersion along multiple pathways, invading with precision defined sites of the embryo to differentiate into many derivatives. This report addresses the involvement of NT-3 in early colonization by cephalic NCCs invading the optic vesicle region. The results of in vitro and in vivo approaches showed that NCCs migrate directionally up an NT-3 concentration gradient. We also demonstrated the expression of NT-3 in the ocular region as well as their functional TrkB, TrkC and p75 receptors on cephalic NCCs. On whole-mount embryo, a perturbed distribution of NCCs colonizing the optic vesicle target field was shown after morpholino cancelation of cephalic NT-3 or TrkC receptor on NCCs, as well as in situ blocking of TrkC receptor of mesencephalic NCCs by specific antibody released from inserted microbeads. The present results strongly suggest that, among other complementary cell guidance factor(s), the chemotactic response of NCCs toward the ocular region NT-3 gradient is essential for spatiotemporal cell orientation, amplifying the functional scope of this neurotrophic factor as a molecular guide for the embryo cells, besides its well-known canonical functions.
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Affiliation(s)
- Juan P Zanin
- Center for Cellular and Molecular Biology - IIBYT (CONICET, UNC), FCEFN, National University of Cordoba, Av. Vélez Sarsfield 1611, 5016 Córdoba, Argentina
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20
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Chung ES, Lee KH, Kim M, Chang EJ, Chung TY, Kim EK, Lee HK. Expression of Neurotrophic Factors and their Receptors in Keratoconic Cornea. Curr Eye Res 2013; 38:743-50. [DOI: 10.3109/02713683.2013.774421] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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21
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Mikami Y, Suzuki S, Ishii Y, Watanabe N, Takahashi T, Isokawa K, Honda MJ. The p75 neurotrophin receptor regulates MC3T3-E1 osteoblastic differentiation. Differentiation 2012; 84:392-9. [PMID: 22906707 DOI: 10.1016/j.diff.2012.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 05/22/2012] [Accepted: 07/01/2012] [Indexed: 01/08/2023]
Abstract
While the role of p75(NTR) signaling in the regulation of nerve-related cell growth and survival has been well documented, its actions in osteoblasts are poorly understood. In this study, we examined the effects of p75(NTR) on osteoblast proliferation and differentiation using the MC3T3-E1 pre-osteoblast cell line. Proliferation and osteogenic differentiation were significantly enhanced in p75(NTR)-overexpressing MC3T3-E1 cells (p75GFP-E1). In addition, expression of osteoblast-specific osteocalcin (OCN), bone sialoprotein (BSP), and osterix mRNA, ALP activity, and mineralization capacity were dramatically enhanced in p75GFP-E1 cells, compared to wild MC3T3-E1 cells (GFP-E1). To determine the binding partner of p75(NTR) in p75GFP-E1 cells during osteogenic differentiation, we examined the expression of trkA, trkB, and trkC that are known binding partners of p75(NTR), as well as NgR. Pharmacological inhibition of trk tyrosine kinase with the K252a inhibitor resulted in marked reduction in the level of ALPase under osteogenic conditions. The deletion of the GDI binding domain in the p75(NTR)-GFP construct had no effect on mineralization. Taken together, our studies demonstrated that p75(NTR) signaling through the trk tyrosine kinase pathway affects osteoblast functions by targeting osteoblast proliferation and differentiation.
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Affiliation(s)
- Yoshikazu Mikami
- Department of Anatomy, Nihon University School of Dentistry, Tokyo, Japan.
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22
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Divergent roles of p75NTR and Trk receptors in BDNF's effects on dendritic spine density and morphology. Neural Plast 2012; 2012:578057. [PMID: 22548193 PMCID: PMC3323862 DOI: 10.1155/2012/578057] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 01/13/2012] [Accepted: 01/13/2012] [Indexed: 01/19/2023] Open
Abstract
Activation of TrkB receptors by brain-derived neurotrophic factor (BDNF) followed by MAPK/ERK signaling increases dendritic spine density and the proportion of mature spines in hippocampal CA1 pyramidal neurons. Considering the opposing actions of p75(NTR) and Trk receptors in several BDNF actions on CNS neurons, we tested whether these receptors also have divergent actions on dendritic spine density and morphology. A function-blocking anti-p75(NTR) antibody (REX) did not affect spine density by itself but it prevented BDNF's effect on spine density. Intriguingly, REX by itself increased the proportion of immature spines and prevented BDNF's effect on spine morphology. In contrast, the Trk receptor inhibitor k-252a increased spine density by itself, and prevented BDNF from further increasing spine density. However, most of the spines in k-252a-treated slices were of the immature type. These effects of k-252a on spine density and morphology required neuronal activity because they were prevented by TTX. These divergent BDNF actions on spine density and morphology are reminiscent of opposing functional signaling by p75(NTR) and Trk receptors and reveal an unexpected level of complexity in the consequences of BDNF signaling on dendritic morphology.
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23
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Activity-dependent transcription of BDNF enhances visual acuity during development. Neuron 2011; 70:455-67. [PMID: 21555072 DOI: 10.1016/j.neuron.2011.02.055] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2011] [Indexed: 01/14/2023]
Abstract
In the developing Xenopus tadpole, conditioning with 20 min of visual stimulation leads to increased proBDNF protein levels in the tectum measured 4 hr later. Following conditioning, the ability to induce direction selectivity in tectal neurons, as well as both retinotectal long-term potentiation and depression, thought to underlie this phenomenon, was strongly facilitated. This facilitation was blocked by knockdown of BDNF expression in tectal neurons. Animals that had been exposed to visual conditioning and subsequently received normal visual input for 7-11 hr exhibited higher spatial frequency thresholds of tectal cell responses to counterphasing gratings than nonconditioned control animals. An improvement in visual acuity was confirmed by enhanced sensitivity to counterphasing gratings in a behavioral test. These results indicate that brief sensory stimulation, by initiating nuclear transcription and de novo protein synthesis of BDNF, can facilitate the refinement of response properties in the developing visual system.
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Mikami Y, Ishii Y, Watanabe N, Shirakawa T, Suzuki S, Irie S, Isokawa K, Honda MJ. CD271/p75(NTR) inhibits the differentiation of mesenchymal stem cells into osteogenic, adipogenic, chondrogenic, and myogenic lineages. Stem Cells Dev 2011; 20:901-13. [PMID: 21142793 DOI: 10.1089/scd.2010.0299] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We describe a novel role for CD271 in the differentiation of mesenchymal stem cells (MSCs), including deciduous dental pulp stem cells (DDPSCs) and murine multipotent MSCs (C3H10T1/2 cells). The CD271(+) subpopulation of deciduous dental pulp cells (CD271(+)/DDPSCs) and the forced expression of CD271 in C3H10T1/2 (10T271) were analyzed by fluorescence-activated cell sorting. CD271 expression was detected in DDPSCs that expressed both CD44 and CD90, simultaneously, and the clonogenic capacity of the CD271(+)/DDPSCs was higher than that of the CD271(-)/DDPSCs that expressed both CD44 and CD90. Further, the differentiation of CD271(+)/DDPSCs into osteoblasts and adipocytes was inhibited although CD271(-)/DDPSCs were capable of differentiating into osteoblasts and adipocytes. CD271 was overexpressed in C3H10T1/2 cells, which have the potential to differentiate into osteoblasts, adipocytes, chondrocytes, and myocytes. CD271 inhibited the differentiation of C3H10T1/2 cells into any of these lineages. These results indicate a role for CD271 in inhibiting the differentiation of MSCs.
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Affiliation(s)
- Yoshikazu Mikami
- Department of Anatomy, Nihon University School of Dentistry, Chyoda-ku, Tokyo, Japan
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25
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Schecterson LC, Bothwell M. Neurotrophin receptors: Old friends with new partners. Dev Neurobiol 2010; 70:332-8. [PMID: 20186712 DOI: 10.1002/dneu.20767] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neurotrophins are important regulators of embryonic development and adult function of most populations of neurons in vertebrate nervous systems. This signaling system regulates many diverse activities, including survival, axon outgrowth, and synaptic plasticity. In mammals, neurotrophin action is mediated by four receptors, p75(NTR), TrkA, TrkB, and TrkC. Although early studies viewed these receptors as solitary agents in the cells outer membrane, recent discoveries reveal that the cell outer membrane is a crowded and highly interactive neighborhood. Neurotrophin receptors partner with a diverse array of membrane proteins, dramatically expanding their functional repertoire. This review will focus on some of the most recent discoveries concerning the promiscuous partnering of neurotrophin receptors.
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Affiliation(s)
- Leslayann C Schecterson
- Department of Physiology & Biophysics, University of Washington, Seattle, Washington 98195, USA
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26
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Dissecting the involvement of tropomyosin-related kinase A and p75 neurotrophin receptor signaling in NGF deficit-induced neurodegeneration. Proc Natl Acad Sci U S A 2010; 107:12299-304. [PMID: 20566851 DOI: 10.1073/pnas.1007181107] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
NGF, the principal neurotrophic factor for basal forebrain cholinergic neurons (BFCNs), has been correlated to Alzheimer's disease (AD) because of the selective vulnerability of BFCNs in AD. These correlative links do not substantiate a comprehensive cause-effect mechanism connecting NGF deficit to overall AD neurodegeneration. A demonstration that neutralizing NGF activity could have consequences beyond a direct interference with the cholinergic system came from studies in the AD11 mouse model, in which the expression of a highly specific anti-NGF antibody determines a neurodegeneration that encompasses several features of human AD. Because the transgenic antibody binds to mature NGF much more strongly than to proNGF and prevents binding of mature NGF to the tropomyosin-related kinase A (TrkA) receptor and to p75 neurotrophin receptor (p75NTR), we postulated that neurodegeneration in AD11 mice is provoked by an imbalance of proNGF/NGF signaling and, consequently, of TrkA/p75NTR signaling. To test this hypothesis, in this study we characterize the phenotype of two lines of transgenic mice, one in which TrkA signaling is inhibited by neutralizing anti-TrkA antibodies and a second one in which anti-NGF mice were crossed to p75NTR(exonIII(-/-)) mice to abrogate p75NTR signaling. TrkA neutralization determines a strong cholinergic deficit and the appearance of beta-amyloid peptide (Abeta) but no tau-related pathology. In contrast, abrogating p75NTR signaling determines a full rescue of the cholinergic and Abeta phenotype of anti-NGF mice, but tau hyperphosphorylation is exacerbated. Thus, we demonstrate that inhibiting TrkA signaling activates Abeta accumulation and that different streams of AD neurodegeneration are related in complex ways to TrkA versus p75NTR signaling.
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Cell-specific targeting in the mouse inner ear using nanoparticles conjugated with a neurotrophin-derived peptide ligand: potential tool for drug delivery. Int J Pharm 2010; 390:214-24. [PMID: 20153412 DOI: 10.1016/j.ijpharm.2010.02.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 02/03/2010] [Accepted: 02/04/2010] [Indexed: 01/19/2023]
Abstract
Cell specific targeting is an emerging field in nanomedicine. Homing of the multifunctional nanoparticles (MFNPs) is achieved by the conjugation of targeting moieties on the nanoparticle surface. The inner ear is an attractive target for new drug delivery strategies as it is hard to access and hearing loss is a significant worldwide problem. In this work we investigated the utility of a Nerve Growth Factor-derived peptide (hNgf_EE) functionalized nanoparticles (NPs) to target cells of the inner ear. These functionalized NPs were introduced to organotypic explant cultures of the mouse inner ear and to PC-12 rat pheochromocytoma cells. The NPs did not show any signs of toxicity. Specific targeting and higher binding affinity to spiral ganglion neurons, Schwann cells and nerve fibers of the explant cultures were achieved through ligand mediated multivalent binding to tyrosine kinase receptors and to p75 neurotrophin receptors. Unspecific uptake of NPs was investigated using NPs conjugated with scrambled hNgf_EE peptide. Our results indicate a selective cochlear cell targeting by MFNPs, which may be a potential tool for cell specific drug and gene delivery to the inner ear.
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Yano H, Torkin R, Martin LA, Chao MV, Teng KK. Proneurotrophin-3 is a neuronal apoptotic ligand: evidence for retrograde-directed cell killing. J Neurosci 2009; 29:14790-802. [PMID: 19940174 PMCID: PMC2824605 DOI: 10.1523/jneurosci.2059-09.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 09/01/2009] [Accepted: 10/13/2009] [Indexed: 12/20/2022] Open
Abstract
Although mature neurotrophins are well described trophic factors that elicit retrograde survival signaling, the precursor forms of neurotrophins (i.e., proneurotrophins) can function as high-affinity apoptotic ligands for selected neural populations. An outstanding question is whether target-derived proneurotrophins might affect neuronal survival/death decisions through a retrograde transport mechanism. Since neurotrophin-3 (NT-3) is highly expressed in non-neural tissues that receive peripheral innervation, we investigated the localized actions of its precursor (proNT-3) on sympathetic neurons in the present study. Pharmacological inhibition of intracellular furin proteinase activity in 293T cells resulted in proNT-3 release instead of mature NT-3, whereas membrane depolarization in cerebellar granule neurons stimulated endogenous proNT-3 secretion, suggesting that proNT-3 is an inducible bona fide ligand in the nervous system. Our data also indicate that recombinant proNT-3 induced sympathetic neuron death that is p75(NTR)- and sortilin-dependent, with hallmark features of apoptosis including JNK (c-Jun N-terminal kinase) activation and nuclear fragmentation. Using compartmentalized culture systems that segregate neuronal cell bodies from axons, proNT-3, acting within the distal axon compartment, elicited sympathetic neuron death and overrode the survival-promoting actions of NGF. Together, these results raise the intriguing possibility that dysregulation of proneurotrophin processing/release by innervated targets can be deleterious to the neurons projecting to these sites.
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Affiliation(s)
- Hiroko Yano
- Molecular Neurobiology Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, New York 10016
| | - Risa Torkin
- Department of Medicine, Weill Cornell Medical College, New York, New York 10065, and
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Laura Andrés Martin
- Department of Medicine, Weill Cornell Medical College, New York, New York 10065, and
| | - Moses V. Chao
- Molecular Neurobiology Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, New York 10016
| | - Kenneth K. Teng
- Department of Medicine, Weill Cornell Medical College, New York, New York 10065, and
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29
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p75 and TrkA signaling regulates sympathetic neuronal firing patterns via differential modulation of voltage-gated currents. J Neurosci 2009; 29:5411-24. [PMID: 19403809 DOI: 10.1523/jneurosci.3503-08.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Neurotrophins such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) act through the tropomyosin-related receptor tyrosine kinases (Trk) and the pan-neurotrophin receptor (p75) to regulate complex developmental and functional properties of neurons. While NGF activates both receptor types in sympathetic neurons, differential signaling through TrkA and p75 can result in widely divergent functional outputs for neuronal survival, growth, and synaptic function. Here we show that TrkA and p75 signaling pathways have opposing effects on the firing properties of sympathetic neurons, and define a mechanism whereby the relative level of signaling through these two receptors sets firing patterns via coordinate regulation of a set of ionic currents. We show that signaling through the p75 pathway causes sympathetic neurons to fire in a phasic pattern showing marked accommodation. Signaling through the NGF-specific TrkA, on the other hand, causes cells to fire tonically. Neurons switch rapidly between firing patterns, on the order of minutes to hours. We show that changes in firing patterns are caused by neurotrophin-dependent regulation of at least four voltage-gated currents: the sodium current and the M-type, delayed rectifier, and calcium-dependent potassium currents. Neurotrophin release, and thus receptor activation, varies among somatic tissues and physiological state. Thus, these data suggest that target-derived neurotrophins may be an important determinant of the characteristic electrical properties of sympathetic neurons and therefore regulate the functional output of the sympathetic nervous system.
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30
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Nerve growth factor in rheumatic diseases. Semin Arthritis Rheum 2009; 40:109-26. [PMID: 19481238 DOI: 10.1016/j.semarthrit.2009.03.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 02/20/2009] [Accepted: 03/16/2009] [Indexed: 01/01/2023]
Abstract
OBJECTIVES The nervous system modulates the immune response in many autoimmune syndromes by neurogenic inflammation. One of the pivotal mediators is nerve growth factor (NGF), which is known for its effects on neuronal survival and growth. There is considerable evidence that NGF acts as an important mediator of many immune responses. This article reviews the role of NGF in rheumatic diseases and strategies for potential therapeutic interventions. METHODS We conducted a database search using Medline and Medpilot. Eight hundred abstracts containing the keyword NGF and 1 of the following terms were reviewed: arthritis, neurogenic inflammation, rheumatoid arthritis, osteoarthritis, collagen arthritis, arteritis, psoriasis, psoriatic arthritis, Sjogren syndrome, systemic lupus erythematosus, gout, osteoporosis, lower back pain, lumbar disc herniation, nerve root compression, spondyloarthritis, spondylarthropathy, algoneurodystrophy, fibromyalgia, Kawasaki syndrome, polyarteritis nodosa, cytokine, vasculitis, pain, therapy, and antagonist. Articles were analyzed based on relevance and content. Most clinical trials and studies with human specimens were included. Studies with experimental animal models were selected if they contained relevant data. RESULTS NGF is overexpressed in many inflammatory and degenerative rheumatic diseases. Concentrations differ to some extent and sometimes even show contradictory results. NGF is found in serum, synovial fluid, and cerebrospinal fluid, and tissue specimens. NGF concentrations can be correlated with the extent of inflammation and/or clinical activity in many conditions. In rheumatoid arthritis, NGF levels are significantly higher as compared with osteoarthritis. CONCLUSIONS NGF is a significant mediator and modulator of inflammation. NGF sometimes shows detrimental and sometimes regenerative activity. These findings indicate potential therapeutic interventions using either NGF antagonists or recombinant NGF.
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Abstract
Neurotrophins were christened in consideration of their actions on the nervous system and, for a long time, they were the exclusive interest of neuroscientists. However, more recently, this family of proteins has been shown to possess essential cardiovascular functions. During cardiovascular development, neurotrophins and their receptors are essential factors in the formation of the heart and critical regulator of vascular development. Postnatally, neurotrophins control the survival of endothelial cells, vascular smooth muscle cells, and cardiomyocytes and regulate angiogenesis and vasculogenesis, by autocrine and paracrine mechanisms. Recent studies suggest the capacity of neurotrophins, via their tropomyosin-kinase receptors, to promote therapeutic neovascularization in animal models of hindlimb ischemia. Conversely, the neurotrophin low-affinity p75(NTR) receptor induces apoptosis of endothelial cells and vascular smooth muscle cells and impairs angiogenesis. Finally, nerve growth factor looks particularly promising in treating microvascular complications of diabetes or reducing cardiomyocyte apoptosis in the infarcted heart. These seminal discoveries have fuelled basic and translational research and thus opened a new field of investigation in cardiovascular medicine and therapeutics. Here, we review recent progress on the molecular signaling and roles played by neurotrophins in cardiovascular development, function, and pathology, and we discuss therapeutic potential of strategies based on neurotrophin manipulation.
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Affiliation(s)
- Andrea Caporali
- Division of Experimental Cardiovascular Medicine, University of Bristol, Bristol, UK
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32
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Dwivedi Y, Rizavi HS, Zhang H, Mondal AC, Roberts RC, Conley RR, Pandey GN. Neurotrophin receptor activation and expression in human postmortem brain: effect of suicide. Biol Psychiatry 2009; 65:319-28. [PMID: 18930453 PMCID: PMC2654767 DOI: 10.1016/j.biopsych.2008.08.035] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 07/31/2008] [Accepted: 08/25/2008] [Indexed: 01/19/2023]
Abstract
BACKGROUND The physiological functions of neurotrophins occur through binding to two receptors: pan75 neurotrophin receptor (p75(NTR)) and a family of tropomyosin receptor kinases (Trks A, B, and C). We recently reported that expression of neurotrophins and TrkB were reduced in brains of suicide subjects. This study examines whether expression and activation of Trk receptors and expression of p75(NTR) are altered in brain of these subjects. METHODS Expression levels of TrkA, B, C, and of p75(NTR) were measured by quantitative reverse transcription polymerase chain reaction and Western blot in prefrontal cortex (PFC) and hippocampus of suicide and normal control subjects. The activation of Trks was determined by immunoprecipitation followed by Western blotting using phosphotyrosine antibody. RESULTS In hippocampus, lower mRNA levels of TrkA and TrkC were observed in suicide subjects. In the PFC, the mRNA level of TrkA was decreased, without any change in TrkC. However, the mRNA level of p75(NTR) was increased in both PFC and hippocampus. Immunolabeling studies showed similar results as observed for the mRNAs. In addition, phosphorylation of all Trks was decreased in hippocampus, but in PFC, decreased phosphorylation was noted only for TrkA and B. Increased expression ratios of p75(NTR) to Trks were also observed in PFC and hippocampus of suicide subjects. CONCLUSIONS Our results suggest not only reduced functioning of Trks in brains of suicide subjects but also that increased ratios of p75(NTR) to Trks indicate possible activation of pathways that are apoptotic in nature. These findings may be crucial in the pathophysiology of suicide.
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Affiliation(s)
- Yogesh Dwivedi
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, Chicago, IL 60612, USA.
| | - Hooriyah S. Rizavi
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago IL, 60612, USA
| | - Hui Zhang
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago IL, 60612, USA
| | - Amal C. Mondal
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago IL, 60612, USA
| | - Rosalinda C. Roberts
- University of Alabama at Birmingham, 865D Sparks Center, 1720 7th Ave South, Birmingham, AL 35294, USA
| | | | - Ghanshyam N. Pandey
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, 1601 W. Taylor St., Chicago IL, 60612, USA
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33
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Barnes M, Eberhart CG, Collins R, Tihan T. Expression of p75NTR in fetal brain and medulloblastomas: evidence of a precursor cell marker and its persistence in neoplasia. J Neurooncol 2008; 92:193-201. [PMID: 19066726 DOI: 10.1007/s11060-008-9755-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Accepted: 11/17/2008] [Indexed: 11/30/2022]
Abstract
p75 neurotrophin receptor (p75NTR) is a member of the tumor necrosis factor superfamily, and plays a significant role in nervous system development. p75NTR has a dual (proliferative/apoptotic) role in neurogenesis and binds pro-neurotrophins with high affinity. Recent work suggests p75NTR is overexpressed in the developing cerebellum and in nodular/desmoplastic medulloblastomas. We analyzed p75NTR expression in various parts of the fetal and adult human central nervous system, and in 75 patients with medulloblastomas. The expression of p75NTR in the fetal brain was seen solely within the external granular layer with weaker expression in the Purkinje layer, which most likely represents Purkinje cell staining. The staining was present in gestational weeks 20-40, while no staining was identified elsewhere in the fetal brain or within the adult cerebellum. p75NTR positive cells were also positive with the proliferation marker ki-67, but were negative for ret, reelin, CD133, CD34, and cleaved caspase 3. Nine of 75 medulloblastomas (12%) were also showed positive immunostaining for p75NTR. The staining was seen in four classic, two desmoplastic, and three anaplastic medulloblastomas. The persistence of p75NTR in a small group of medulloblastomas raises the possibility that in such tumors, the receptor could be a potential therapeutic target.
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Affiliation(s)
- Michael Barnes
- Department of Pathology, UCSF Medical Center, San Francisco, CA, USA.
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34
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Lombardi L, De Stefano ME, Paggi P. Components of the NGF signaling complex are altered in mdx mouse superior cervical ganglion and its target organs. Neurobiol Dis 2008; 32:402-11. [PMID: 18725298 DOI: 10.1016/j.nbd.2008.07.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 07/11/2008] [Accepted: 07/29/2008] [Indexed: 01/19/2023] Open
Abstract
We previously reported that in the superior cervical ganglion (SCG) of dystrophic mdx mice, which lack full-length dystrophin, there is a loss of neurons projecting to SCG muscular targets, like the iris. Nonetheless, surviving neurons, innervating either iris or submandibular gland (SuGl), a SCG non-muscular target, underwent reduced axon defasciculation and terminal branching. Here we report that, during early post-natal development, levels of pro-apoptotic proNGF in mdx mouse iris, but not in the SuGl, are higher than in the wild-type. This increase, along with reduced levels of NGF receptors (TrkA and p75NTR) in SCG, may be partly responsible for the observed loss of neurons projecting to the iris. These alterations, combined with a reduction in polysialylated-NCAM and neurofilament protein levels in SCG, may also account for reduced axon defasciculation and terminal branching in mdx mouse SCG targets.
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MESH Headings
- Animals
- Blotting, Western
- Dyneins/genetics
- Dyneins/metabolism
- Electrophoresis, Polyacrylamide Gel
- Enzyme-Linked Immunosorbent Assay
- Gene Expression
- Immunohistochemistry
- Iris/innervation
- Iris/metabolism
- Male
- Mice
- Mice, Inbred mdx
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/metabolism
- Nerve Growth Factor/biosynthesis
- Nerve Growth Factor/genetics
- Nerve Growth Factor/metabolism
- Neural Cell Adhesion Molecule L1/genetics
- Neural Cell Adhesion Molecule L1/metabolism
- Protein Precursors/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, trkA/biosynthesis
- Receptor, trkA/genetics
- Receptor, trkA/metabolism
- Receptors, Nerve Growth Factor/biosynthesis
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sialic Acids/genetics
- Sialic Acids/metabolism
- Signal Transduction
- Submandibular Gland/innervation
- Submandibular Gland/metabolism
- Superior Cervical Ganglion/metabolism
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Affiliation(s)
- Loredana Lombardi
- Dipartimento di Biologia Cellulare e dello Sviluppo, Sapienza Università di Roma, Italy
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35
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Powell JC, Twomey C, Jain R, McCarthy JV. Association between Presenilin-1 and TRAF6 modulates regulated intramembrane proteolysis of the p75NTR neurotrophin receptor. J Neurochem 2008; 108:216-30. [PMID: 19012753 DOI: 10.1111/j.1471-4159.2008.05763.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The p75 neurotrophin receptor (p75(NTR)) is a member of the tumour necrosis factor superfamily, which relies on the recruitment of cytosolic protein partners including the tumour necrosis factor receptor-associated factor 6 (TRAF6) E3 ubiquitin ligase to produce cellular responses. Recently, p75(NTR) was also shown to undergo presenilin-dependent, gamma-secretase-mediated regulated intramembrane proteolysis. In this study, we report the characterization of a highly conserved TRAF6-binding site (PxExxAr/Ac) in presenilin-1 (PS1) that mediates nerve growth factor (NGF)-induced association between PS1 and TRAF6. We demonstrate that disruption of this interaction between PS1 and TRAF6 inhibits TRAF6 autoubiquitination and gamma-secretase cleavage of p75(NTR). Additionally, we show that PS1-deficiency antagonizes NGF-induced I-kappaB degradation. Finally, we also show that p75(NTR) is a substrate for TRAF6-mediated ubiquitination and that TRAF6 E3 ligase activity is required for regulated intramembrane proteolysis of p75(NTR). In summary, our data suggest that an NGF-induced association between PS1 and TRAF6 influences regulated intramembrane proteolysis of p75(NTR).
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Affiliation(s)
- James C Powell
- Signal Transduction Laboratory, Biochemistry Department, University College Cork, Cork, Ireland
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36
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Wilson-Gerwing TD, Stucky CL, McComb GW, Verge VMK. Neurotrophin-3 significantly reduces sodium channel expression linked to neuropathic pain states. Exp Neurol 2008; 213:303-14. [PMID: 18601922 DOI: 10.1016/j.expneurol.2008.06.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 04/29/2008] [Accepted: 06/06/2008] [Indexed: 10/21/2022]
Abstract
Neuropathic pain resulting from chronic constriction injury (CCI) is critically linked to sensitization of peripheral nociceptors. Voltage gated sodium channels are major contributors to this state and their expression can be upregulated by nerve growth factor (NGF). We have previously demonstrated that neurotrophin-3 (NT-3) acts antagonistically to NGF in modulation of aspects of CCI-induced changes in trkA-associated nociceptor phenotype and thermal hyperalgesia. Thus, we hypothesized that exposure of neurons to increased levels of NT-3 would reduce expression of Na(v)1.8 and Na(v)1.9 in DRG neurons subject to CCI. In adult male rats, Na(v)1.8 and Na(v)1.9 mRNAs are expressed at high levels in predominantly small to medium size neurons. One week following CCI, there is reduced incidence of neurons expressing detectable Na(v)1.8 and Na(v)1.9 mRNA, but without a significant decline in mean level of neuronal expression, and similar findings observed immunohistochemically. There is also increased accumulation/redistribution of channel protein in the nerve most apparent proximal to the first constriction site. Intrathecal infusion of NT-3 significantly attenuates neuronal expression of Na(v)1.8 and Na(v)1.9 mRNA contralateral and most notably, ipsilateral to CCI, with a similar impact on relative protein expression at the level of the neuron and constricted nerve. We also observe reduced expression of the common neurotrophin receptor p75 in response to CCI that is not reversed by NT-3 in small to medium sized neurons and may confer an enhanced ability of NT-3 to signal via trkA, as has been previously shown in other cell types. These findings are consistent with an analgesic role for NT-3.
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Affiliation(s)
- Tracy D Wilson-Gerwing
- Department of Anatomy and Cell Biology, Cameco MS Neuroscience Research Center University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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37
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Neurotrophin-induced upregulation of p75NTR via a protein kinase C-delta-dependent mechanism. Brain Res 2008; 1217:10-24. [PMID: 18511024 DOI: 10.1016/j.brainres.2008.03.076] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 02/27/2008] [Accepted: 03/28/2008] [Indexed: 02/06/2023]
Abstract
Neurotrophins exert their biological effects via p75NTR and Trk receptors. Functional interplay between these two receptors has been widely explored with respect to p75NTR enhancing the activation and signalling of Trk, but few studies address the bidirectional aspects. We have previously demonstrated that the expression of p75NTR can be differentially modulated by different Trk receptor mutations. Here we investigate the mechanism of Nerve Growth Factor (NGF)-induced upregulation of p75NTR expression. We utilize pharmacological inhibition to investigate the role of various TrkA-associated signalling intermediates in this regulatory cascade. Notably, the inhibition of phospholipase C-gamma (PLC-gamma) using U73122, prevented the NGF-induced upregulation of p75NTR protein and mRNA. The inhibition of protein kinase C-delta (PKC-delta) activation by rottlerin, a selective PKC-delta inhibitor, and by small interfering RNA (siRNA) directed against PKC-delta also inhibited this NGF-induced upregulation. Finally, we also show that in cerebellar granule neurons, BDNF acting via TrkB increases p75NTR expression in a PKC-delta dependent manner. These results indicate the importance of Trk-dependent PLC-gamma and PKC-delta activation for downstream regulation of p75NTR protein expression in response to neurotrophin stimulation, a process that has implications to the survival and growth of the developing nervous system.
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38
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Sandoval M, Sandoval R, Thomas U, Spilker C, Smalla KH, Falcon R, Marengo JJ, Calderón R, Saavedra V, Heumann R, Bronfman F, Garner CC, Gundelfinger ED, Wyneken U. Antagonistic effects of TrkB and p75NTRon NMDA receptor currents in post-synaptic densities transplanted into Xenopus oocytes. J Neurochem 2007; 101:1672-84. [PMID: 17394529 DOI: 10.1111/j.1471-4159.2007.04519.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) and its receptor TrkB are essential regulators of synaptic function in the adult CNS. A TrkB-mediated effect at excitatory synapses is enhancement of NMDA receptor (NMDA-R)-mediated currents. Recently, opposing effects of TrkB and the pan-neurotrophin receptor p75(NTR) on long-term synaptic depression and long-term potentiation have been reported in the hippocampus. To further study the regulation of NMDA-Rs by neurotrophin receptors in their native protein environment, we micro-transplanted rat forebrain post-synaptic densities (PSDs) into Xenopus oocytes. One-minute incubations of oocytes with BDNF led to dual effects on NMDA-R currents: either TrkB-dependent potentiation or TrkB-independent inhibition were observed. Pro-nerve growth factor, a ligand for p75(NTR) but not for TrkB, produced a reversible, dose-dependent, TrkB-independent and p75(NTR)-dependent inhibition of NMDA-Rs. Fractionation experiments showed that p75(NTR) is highly enriched in the PSD protein fraction. Immunoprecipitation and pull-down experiments further revealed that p75(NTR) is a core component of the PSD, where it interacts with the PDZ3 domain of the scaffolding protein SAP90/PSD-95. Our data provide striking evidence for a rapid inhibitory effect of p75(NTR) on NMDA-R currents that antagonizes TrkB-mediated NMDA-R potentiation. These opposing mechanisms might be present in a large proportion of forebrain synapses and may contribute importantly to synaptic plasticity.
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Affiliation(s)
- Mauricio Sandoval
- Laboratorio de Neurociencias, Universidad de Los Andes, Santiago, Chile
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39
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Kuo LT, Groves MJ, Scaravilli F, Sugden D, An SF. Neurotrophin-3 administration alters neurotrophin, neurotrophin receptor and nestin mRNA expression in rat dorsal root ganglia following axotomy. Neuroscience 2007; 147:491-507. [PMID: 17532148 DOI: 10.1016/j.neuroscience.2007.04.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Revised: 04/13/2007] [Accepted: 04/13/2007] [Indexed: 02/02/2023]
Abstract
In the months following transection of adult rat peripheral nerve some sensory neurons undergo apoptosis. Two weeks after sciatic nerve transection some neurons in the L4 and L5 dorsal root ganglia begin to show immunoreactivity for nestin, a filament protein expressed by neuronal precursors and immature neurons, which is stimulated by neurotrophin-3 (NT-3) administration. The aim of this study was to examine whether NT-3 administration could be compensating for decreased production of neurotrophins or their receptors after axotomy, and to determine the effect on nestin synthesis. The levels of mRNA in the ipsilateral and contralateral L4 and L5 dorsal root ganglia were analyzed using real-time polymerase chain reaction, 1 day, 1, 2 and 4 weeks after unilateral sciatic nerve transection and NT-3 or vehicle administration via s.c. micro-osmotic pumps. In situ hybridization was used to identify which cells and neurons expressed mRNAs of interest, and the expression of full-length trkC and p75NTR protein was investigated using immunohistochemistry. Systemic NT-3 treatment increased the expression of brain-derived neurotrophic factor, nestin, trkA, trkB and trkC mRNA in ipsilateral ganglia compared with vehicle-treated animals. Some satellite cells surrounding neurons expressed trkA and trkC mRNA and trkC immunoreactivity. NT-3 administration did not affect neurotrophin mRNA levels in the contralateral ganglia, but decreased the expression of trkA mRNA and increased the expression of trkB mRNA and p75NTR mRNA and protein. These data suggest that systemically administered NT-3 may counteract the decrease, or even increase, neurotrophin responsiveness in both ipsi- and contralateral ganglia after nerve injury.
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MESH Headings
- Animals
- Axotomy
- Brain-Derived Neurotrophic Factor/biosynthesis
- DNA Primers
- Functional Laterality/physiology
- Ganglia, Spinal/cytology
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Immunohistochemistry
- In Situ Hybridization
- Intermediate Filament Proteins/biosynthesis
- Male
- Nerve Growth Factors/biosynthesis
- Nerve Tissue Proteins/biosynthesis
- Nestin
- Neurotrophin 3/administration & dosage
- Neurotrophin 3/pharmacology
- RNA, Messenger/biosynthesis
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor/biosynthesis
- Receptor, trkA/biosynthesis
- Receptor, trkB/biosynthesis
- Receptor, trkC/biosynthesis
- Receptors, Nerve Growth Factor/biosynthesis
- Sciatic Nerve/injuries
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Affiliation(s)
- L-T Kuo
- Department of Molecular Neuroscience, Division of Neuropathology, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
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40
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Wehrman T, He X, Raab B, Dukipatti A, Blau H, Garcia KC. Structural and mechanistic insights into nerve growth factor interactions with the TrkA and p75 receptors. Neuron 2007; 53:25-38. [PMID: 17196528 DOI: 10.1016/j.neuron.2006.09.034] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2006] [Revised: 08/15/2006] [Accepted: 09/22/2006] [Indexed: 12/23/2022]
Abstract
Nerve growth factor engages two structurally distinct transmembrane receptors, TrkA and p75, which have been proposed to create a "high-affinity" NGF binding site through formation of a ternary TrkA/NGF/p75 complex. To define a structural basis for the high-affinity site, we have determined the three-dimensional structure of a complete extracellular domain of TrkA complexed with NGF. The complex reveals a crab-shaped homodimeric TrkA structure, but a mechanism for p75 coordination is not obvious. We investigated the heterodimerization of membrane-bound TrkA and p75, on intact mammalian cells, using a beta-gal protein-protein interaction system. We find that NGF dimerizes TrkA and that p75 exists on the cell surface as a preformed oligomer that is not dissociated by NGF. We find no evidence for a direct TrkA/p75 interaction. We propose that TrkA and p75 likely communicate through convergence of downstream signaling pathways and/or shared adaptor molecules, rather than through direct extracellular interactions.
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Affiliation(s)
- Tom Wehrman
- Baxter Laboratory for Genetic Pharmacology, Department of Microbiology and Immunology, The Stem Cell Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
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41
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Abstract
Neurotrophins provide trophic and tropic support for different neuronal subpopulations in the developing and adult nervous systems. Expression of the neurotrophins and their receptors can be altered in several different disease or injury states that impact upon the functions in the central and peripheral nervous systems. The intracellular signals used by the neurotrophins are triggered by ligand binding to the cell surface Trk and p75NTR receptors. In general, signals emanating from Trk receptors support survival, growth and synaptic strengthening, while those emanating from p75NTR induce apoptosis, attenuate growth and weaken synaptic signaling. Mature neurotrophins are the preferred ligand for Trk proteins while p75NTR binds preferentially to the proneurotrophins and serves as a signaling component of the receptor complex for growth inhibitory molecules of central nervous system myelin [ie, myelin-associated glycoprotein (MAG), oligodendrocyte-myelin glycoprotein (OMgP) and Nogo]. The functional antagonism between Trk and p75NTR signaling may significantly impact the pathogenesis of human neurodevelopmental and neurodegenerative diseases and further complicate therapeutic uses of exogenous neurotrophins. The potential for each is discussed in this review.
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Affiliation(s)
- Jeffery L Twiss
- Nemours Biomedical Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803, USA.
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42
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Scott ALM, Ramer LM, Soril LJJ, Kwiecien JM, Ramer MS. Targeting myelin to optimize plasticity of spared spinal axons. Mol Neurobiol 2006; 33:91-111. [PMID: 16603791 DOI: 10.1385/mn:33:2:91] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Revised: 11/30/1999] [Accepted: 07/18/2005] [Indexed: 01/30/2023]
Abstract
Functional re-innervation of target neurons following neurological damage such as spinal cord injury is an essential requirement of potential therapies. There are at least two avenues by which this can be achieved: (a) through the regeneration of injured axons and (b) through promoting plasticity of those spared by the initial insult. There are several reasons why the latter approach may be more feasible, not the least of which are the inhibitory character of the glial scar, the often long distances over which injured axons must regrow, and the fact that spared axons are often already in the vicinity of denervated targets. The challenge is to unveil the well-recognized intrinsic plasticity of spared axons in a way that avoids complications, such as pain or autonomic dysfunction. One approach that we as well as others have taken is to target growth-suppressing signaling pathways initiated in spared axons by myelin-derived proteins. This article reviews models used for the study of spinal axon plasticity and describes the anatomical and behavioral effects of interfering with myelinderived proteins, their receptors, and components of their intracellular signaling cascades.
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Affiliation(s)
- Angela L M Scott
- International Collaboration on Repair Discoveries, The University of British Columbia, Vancouver, Canada
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43
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Lebrun B, Bariohay B, Moyse E, Jean A. Brain-derived neurotrophic factor (BDNF) and food intake regulation: A minireview. Auton Neurosci 2006; 126-127:30-8. [PMID: 16632412 DOI: 10.1016/j.autneu.2006.02.027] [Citation(s) in RCA: 153] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Accepted: 02/27/2006] [Indexed: 10/24/2022]
Abstract
Neurotrophins, and in particular BDNF, play important roles in proliferation, differentiation and survival of neurons during development, as well as in the synaptic activity and plasticity in many groups of mature neurons. Several lines of evidence suggest that BDNF and its high affinity receptor TrkB contribute to food intake and body weight control. In rodents, pharmacological treatments with BDNF induce reduction in food intake, whereas genetic models with an altered BDNF/TrkB signalling display hyperphagia and obesity. Genetic studies in humans have shown that mutations in the BDNF or TrkB genes may account for certain types of obesity or other forms of eating disorders. Since circulating levels of BDNF correlate with eating disorders in humans and peripheral BDNF treatments reduce hyperphagia and hyperglycaemia in obese diabetic rodents, an endocrine role of BDNF appears plausible and requires further investigation. A central anorectic action of BDNF has also been documented, with a primary focus on the hypothalamus and a more recent highlight on the brainstem integrator of energy homeostasis, the dorsal vagal complex. In this review, we will briefly present neurotrophins and their receptors and focus on experimental evidence which point out BDNF as a signalling component of food intake regulation, with a particular emphasis on the localization of the central anorectic action of BDNF.
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Affiliation(s)
- Bruno Lebrun
- Laboratoire de Physiologie Neurovégétative (PNV), UMR Université Paul Cézanne Aix, Marseille III, CNRS (UMR 6153), INRA (UMR 1147), Faculté des sciences et techniques, BP 351, 13397 Marseille cedex 20, France.
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44
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Moore K, MacSween M, Shoichet M. Immobilized concentration gradients of neurotrophic factors guide neurite outgrowth of primary neurons in macroporous scaffolds. ACTA ACUST UNITED AC 2006; 12:267-78. [PMID: 16548685 DOI: 10.1089/ten.2006.12.267] [Citation(s) in RCA: 179] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Neurotrophic factors present as concentration gradients are neurotropic cues that direct axonal growth toward their targets. Multiple factors work together in vivo to ensure axons reach the proper targets, likely interacting with one another via intracellular signalling pathways. Nerve growth factor (NGF) and neurotrophin-3 (NT-3) are neurotrophins known to guide axons as well as promote axonal growth following injury to both the spinal cord and peripheral nerve. These molecules interact with neurons through different tyrosine kinase receptors. In this study, the receptors for these growth factors were shown to be co-localized on E10 chick dorsal root ganglion (DRG) cells, providing an opportunity for synergism. Well-defined concentration gradients of NGF and NT-3 were immobilized for the first time in a cell-penetrable, cell-adhesive scaffold of poly(2-hydroxyethylmethacrylate) and poly(L-lysine). An NGF concentration gradient of 310 ng/mL/mm was required to guide chick DRG neurites. A lower concentration gradient of 200 ng/mL/mm of NGF was shown to elicit guidance when an NT-3 concentration gradient of 200 ng/mL/mm was also present, indicating a synergistic response in the DRG neurons. These gradient scaffolds may be useful for guided regeneration following injury to the spinal cord or peripheral nerve and may also elucidate the mechanism for intracellular signaling of neurotrophic factors.
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Affiliation(s)
- Kathryn Moore
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Ontario, Canada
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45
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Cui Q. Actions of neurotrophic factors and their signaling pathways in neuronal survival and axonal regeneration. Mol Neurobiol 2006; 33:155-79. [PMID: 16603794 DOI: 10.1385/mn:33:2:155] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 11/30/1999] [Accepted: 08/15/2005] [Indexed: 02/05/2023]
Abstract
Adult axons in the mammalian central nervous system do not elicit spontaneous regeneration after injury, although many affected neurons have survived the neurotrauma. However, axonal regeneration does occur under certain conditions. These conditions include: (a) modification of regrowth environment, such as supply of peripheral nerve bridges and transplantation of Schwann cells or olfactory ensheathing glia to the injury site; (b) application of neurotrophic factors at the cell soma and axon tips; (c) blockade of growth-inhibitory molecules such as Nogo-A, myelin-associated glycoprotein, and oligodendrocyte-myelin glycoprotein; (d) prevention of chondroitin-sulfate-proteoglycans-related scar tissue formation at the injury site using chondroitinase ABC; and (e) elevation of intrinsic growth potential of injured neurons via increasing intracellular cyclic adenosine monophosphate level. A large body of evidence suggests that these conditions achieve enhanced neuronal survival and axonal regeneration through sometimes overlapping and sometimes distinct signal transduction mechanisms, depending on the targeted neuronal populations and intervention circumstances. This article reviews the available information on signal transduction pathways underlying neurotrophic-factor-mediated neuronal survival and neurite outgrowth/axonal regeneration. Better understanding of signaling transduction is important in helping us develop practical therapeutic approaches for encouraging neuronal survival and axonal regeneration after traumatic injury in clinical context.
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Affiliation(s)
- Qi Cui
- Laboratory for Neural Repair, Shantou University Medical College, China.
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46
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Skoff AM, Adler JE. Nerve growth factor regulates substance P in adult sensory neurons through both TrkA and p75 receptors. Exp Neurol 2005; 197:430-6. [PMID: 16300761 DOI: 10.1016/j.expneurol.2005.10.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Revised: 08/29/2005] [Accepted: 10/04/2005] [Indexed: 12/30/2022]
Abstract
Expression of the nociceptive peptide, substance P (SP) is regulated by the neurotrophin, nerve growth factor (NGF), and exogenous exposure to high levels of NGF increases its cellular content and release. NGF utilizes two receptors, the NGF-specific tyrosine kinase receptor, TrkA, and also the non-specific neurotrophin receptor, p75(NTR) (p75). The purpose of this study is to determine the relative involvement of these receptors in nociception. To investigate the role of TrkA in SP signaling, sensory neurons from adult rats were grown in vitro and exposed to a TrkA-blocking antibody. Pretreatment with the antibody inhibited NGF-induced SP elevation. Furthermore, when neurons were exposed to K252a, a relatively specific TrkA kinase inhibitor, the NGF effect on SP was also inhibited. K252a did not prevent SP up-regulation in cells exposed to forskolin or glial cell line-derived neurotrophic factor (GDNF), two agents which increase SP expression independently of TrkA. When p75 was blocked by antiserum, SP up-regulation by NGF was also inhibited. The antiserum neither impacted neuronal survival or basal levels of SP expression, nor did it inhibit SP up-regulation induced by forskolin. Two other neurotrophins, which are also ligands for p75, brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) did not block NGF-induced SP up-regulation, raising the possibility that activated p75 is able to cooperate in SP regulation regardless of which neurotrophin ligand occupies it. Our data suggest that NGF up-regulation of SP expression requires the involvement of both TrkA and p75, although the specific contribution of each receptor to SP signaling remains to be determined.
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Affiliation(s)
- Anne M Skoff
- Department of Neurology, Wayne State University School of Medicine, 8D University Health Center, 4201 St. Antoine, Detroit, MI 48201, USA.
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47
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Zaccaro MC, Lee HB, Pattarawarapan M, Xia Z, Caron A, L'Heureux PJ, Bengio Y, Burgess K, Saragovi HU. Selective Small Molecule Peptidomimetic Ligands of TrkC and TrkA Receptors Afford Discrete or Complete Neurotrophic Activities. ACTA ACUST UNITED AC 2005; 12:1015-28. [PMID: 16183026 DOI: 10.1016/j.chembiol.2005.06.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2004] [Revised: 06/28/2005] [Accepted: 06/28/2005] [Indexed: 01/08/2023]
Abstract
We designed a minilibrary of 55 small molecule peptidomimetics based on beta-turns of the neurotrophin growth factor polypeptides neurotrophin-3 (NT-3) and nerve growth factor (NGF). Direct binding, binding competition, and biological screens identified agonistic ligands of the ectodomain of the neurotrophin receptors TrkC and TrkA. Agonism is intrinsic to the peptidomimetic ligand (in the absence of neurotrophins), and/or can also be detected as potentiation of neurotrophin action. Remarkably, some peptidomimetics afford both neurotrophic activities of cell survival and neuronal differentiation, while others afford discrete signals leading to either survival or differentiation. The high rate of hits identified suggests that focused minilibraries may be desirable for developing bioactive ligands of cell surface receptors. Small, selective, proteolytically stable ligands with defined biological activity may have therapeutic potential.
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Affiliation(s)
- Maria Clara Zaccaro
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
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48
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Woo NH, Teng HK, Siao CJ, Chiaruttini C, Pang PT, Milner TA, Hempstead BL, Lu B. Activation of p75NTR by proBDNF facilitates hippocampal long-term depression. Nat Neurosci 2005; 8:1069-77. [PMID: 16025106 DOI: 10.1038/nn1510] [Citation(s) in RCA: 591] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2005] [Accepted: 06/28/2005] [Indexed: 12/15/2022]
Abstract
Pro- and mature brain-derived neurotrophic factor (BDNF) activate two distinct receptors: p75 neurotrophin receptor (p75(NTR)) and TrkB. Mature BDNF facilitates hippocampal synaptic potentiation through TrkB. Here we report that proBDNF, by activating p75(NTR), facilitates hippocampal long-term depression (LTD). Electron microscopy showed that p75(NTR) localized in dendritic spines, in addition to afferent terminals, of CA1 neurons. Deletion of p75(NTR) in mice selectively impaired the NMDA receptor-dependent LTD, without affecting other forms of synaptic plasticity. p75(NTR-/-) mice also showed a decrease in the expression of NR2B, an NMDA receptor subunit uniquely involved in LTD. Activation of p75(NTR) by proBDNF enhanced NR2B-dependent LTD and NR2B-mediated synaptic currents. These results show a crucial role for proBDNF-p75(NTR) signaling in LTD and its potential mechanism, and together with the finding that mature BDNF promotes synaptic potentiation, suggest a bidirectional regulation of synaptic plasticity by proBDNF and mature BDNF.
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Affiliation(s)
- Newton H Woo
- Section on Neural Development and Plasticity, LCSN, NICHD, Porter Neuroscience Research Center, 35 Lincoln Drive, Bethesda, Maryland 20892-3714, USA
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49
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Pedraza CE, Podlesniy P, Vidal N, Arévalo JC, Lee R, Hempstead B, Ferrer I, Iglesias M, Espinet C. Pro-NGF isolated from the human brain affected by Alzheimer's disease induces neuronal apoptosis mediated by p75NTR. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 166:533-43. [PMID: 15681836 PMCID: PMC1602327 DOI: 10.1016/s0002-9440(10)62275-4] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The pro-form of nerve growth factor (pro-NGF) has been shown to be a high affinity ligand for p75NTR and to induce apoptosis through this receptor. It has been reported that pro-NGF, rather than mature NGF, is the predominant form of this neurotrophin in human brain. In the present work we studied the potential involvement of pro-NGF purified from human brains affected by Alzheimer's disease (AD), where it is especially abundant, in the neuronal apoptosis observed in this disease. Western blot analysis of human brain tissue showed the existence of several pro-NGF forms. Some of these pro-NGF forms were significantly increased in AD brain cortex in a disease stage-dependent manner. Pro-NGF, purified by chromatography from human AD brains, induced apoptotic cell death in sympathetic neurons and in a p75NTR stably transfected cell line. Blocking p75NTR in cell culture abolished neuronal apoptosis caused by pro-NGF. p75NTR-transfected cells underwent apoptosis in the presence of pro-NGF while control wild-type cells did not. Taken together, these results indicate that pro-NGF purified from AD human brains can induce apoptosis in neuronal cell cultures through its interaction with the p75NTR receptor.
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Affiliation(s)
- Carlos E Pedraza
- Laboratori de Neuropatología Molecular, Departament de Ciències Mèdiques Bàsiques, Universitat de Lleida, C/ Montserrat Roig 2, 25008 Lleida, Spain
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50
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Ahmed Z, Dent RG, Suggate EL, Barrett LB, Seabright RJ, Berry M, Logan A. Disinhibition of neurotrophin-induced dorsal root ganglion cell neurite outgrowth on CNS myelin by siRNA-mediated knockdown of NgR, p75NTR and Rho-A. Mol Cell Neurosci 2005; 28:509-23. [PMID: 15737741 DOI: 10.1016/j.mcn.2004.11.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Revised: 10/20/2004] [Accepted: 11/01/2004] [Indexed: 12/12/2022] Open
Abstract
The presence of multiple axon growth inhibitors may partly explain why central nervous system axons are generally incapable of regenerating after injury. Using RNA interference (RNAi) in dorsal root ganglia neurons (DRGN), we demonstrate siRNA-mediated silencing of components of the inhibitory signalling cascade, including p75NTR, NgR and Rho-A mRNA, of 70%, 100% and 100% of the relevant protein, respectively, while changes in neither protein levels nor cellular immunoreactivity were detected using the relevant scrambled siRNA control sequences. Importantly, after 48 h in culture after siRNA-mediated knockdown of Rho-A, neurite outgrowth was enhanced by 30% compared to that after p75NTR and 50% after NgR silencing. By 3 days, a 5-, 3.5- and 6.5-fold increase in betaIII-tubulin protein levels were observed compared to controls without siRNA after knockdown of p75NTR, NgR and Rho-A, respectively. Together, these results suggest that Rho-A knockdown might be the most effective target for a disinhibition strategy to promote CNS axon regeneration in vivo.
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MESH Headings
- Animals
- Cells, Cultured
- Down-Regulation/drug effects
- Down-Regulation/physiology
- Feedback, Physiological/drug effects
- Feedback, Physiological/physiology
- GPI-Linked Proteins
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/ultrastructure
- Myelin Proteins/metabolism
- Myelin Proteins/pharmacology
- Nerve Growth Factors/pharmacology
- Nerve Growth Factors/physiology
- Nerve Regeneration/drug effects
- Nerve Regeneration/physiology
- Neurites/drug effects
- Neurites/metabolism
- Nogo Receptor 1
- RNA, Small Interfering/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor
- Receptors, Cell Surface
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/metabolism
- Receptors, Peptide/genetics
- Receptors, Peptide/metabolism
- Tubulin/metabolism
- Up-Regulation/drug effects
- Up-Regulation/physiology
- rhoA GTP-Binding Protein/genetics
- rhoA GTP-Binding Protein/metabolism
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Affiliation(s)
- Zubair Ahmed
- Molecular Neuroscience Group, Department of Medicine, University of Birmingham, 3rd Floor Wolfson Research Laboratories, Queen Elizabeth Medical Centre, Edgbaston, Birmingham B15 2TH, UK.
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