1
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Li Y, Li YJ, Zhu ZQ. To re-examine the intersection of microglial activation and neuroinflammation in neurodegenerative diseases from the perspective of pyroptosis. Front Aging Neurosci 2023; 15:1284214. [PMID: 38020781 PMCID: PMC10665880 DOI: 10.3389/fnagi.2023.1284214] [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: 08/28/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023] Open
Abstract
Neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and motor neuron disease, are diseases characterized by neuronal damage and dysfunction. NDs are considered to be a multifactorial disease with diverse etiologies (immune, inflammatory, aging, genetic, etc.) and complex pathophysiological processes. Previous studies have found that neuroinflammation and typical microglial activation are important mechanisms of NDs, leading to neurological dysfunction and disease progression. Pyroptosis is a new mode involved in this process. As a form of programmed cell death, pyroptosis is characterized by the expansion of cells until the cell membrane bursts, resulting in the release of cell contents that activates a strong inflammatory response that promotes NDs by accelerating neuronal dysfunction and abnormal microglial activation. In this case, abnormally activated microglia release various pro-inflammatory factors, leading to the occurrence of neuroinflammation and exacerbating both microglial and neuronal pyroptosis, thus forming a vicious cycle. The recognition of the association between pyroptosis and microglia activation, as well as neuroinflammation, is of significant importance in understanding the pathogenesis of NDs and providing new targets and strategies for their prevention and treatment.
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Affiliation(s)
- Yuan Li
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- College of Anesthesiology, Zunyi Medical University, Zunyi, China
| | - Ying-Jie Li
- Department of General Surgery, Mianyang Hospital of Traditional Chinese Medicine, Mianyang, China
| | - Zhao-Qiong Zhu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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2
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Mercurio S. SOX2-Sensing: Insights into the Role of SOX2 in the Generation of Sensory Cell Types in Vertebrates. Int J Mol Sci 2023; 24:ijms24087637. [PMID: 37108798 PMCID: PMC10141063 DOI: 10.3390/ijms24087637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/17/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
The SOX2 transcription factor is a key regulator of nervous system development, and its mutation in humans leads to a rare disease characterized by severe eye defects, cognitive defects, hearing defects, abnormalities of the CNS and motor control problems. SOX2 has an essential role in neural stem cell maintenance in specific regions of the brain, and it is one of the master genes required for the generation of induced pluripotent stem cells. Sox2 is expressed in sensory organs, and this review will illustrate how it regulates the differentiation of sensory cell types required for hearing, touching, tasting and smelling in vertebrates and, in particular, in mice.
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Affiliation(s)
- Sara Mercurio
- Department of Biotechnologies and Biosciences, University of Milan-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
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3
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Papalampropoulou-Tsiridou M, Shiers S, Wang F, Godin AG, Price TJ, De Koninck Y. Distribution of acid-sensing ion channel subunits in human sensory neurons contrasts with that in rodents. Brain Commun 2022; 4:fcac256. [PMID: 36337346 PMCID: PMC9629378 DOI: 10.1093/braincomms/fcac256] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/27/2022] [Accepted: 10/26/2022] [Indexed: 11/28/2022] Open
Abstract
Acid-sensing ion channels (ASICs) play a critical role in nociception in human sensory neurons. Four genes (ASIC1, ASIC2, ASIC3, and ASIC4) encoding multiple subunits through alternative splicing have been identified in humans. Real time-PCR experiments showed strong expression of three subunits ASIC1, ASIC2, and ASIC3 in human dorsal root ganglia; however, their detailed expression pattern in different neuronal populations has not been investigated yet. In the current study, using an in situ hybridization approach (RNAscope), we examined the presence of ASIC1, ASIC2, and ASIC3 mRNA in three subpopulations of human dorsal root ganglia neurons. Our results revealed that ASIC1 and ASIC3 were present in the vast majority of dorsal root ganglia neurons, while ASIC2 was only expressed in less than half of dorsal root ganglia neurons. The distribution pattern of the three ASIC subunits was the same across the three populations of dorsal root ganglia neurons examined, including neurons expressing the REarranged during Transfection (RET) receptor tyrosine kinase, calcitonin gene-related peptide, and a subpopulation of nociceptors expressing Transient Receptor Potential Cation Channel Subfamily V Member 1. These results strongly contrast the expression pattern of Asics in mice since our previous study demonstrated differential distribution of Asics among the various subpopulation of dorsal root ganglia neurons. Given the distinct acid-sensitivity and activity dynamics among different ASIC channels, the expression differences between human and rodents should be taken under consideration when evaluating the translational potential and efficiency of drugs targeting ASICs in rodent studies.
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Affiliation(s)
- Melina Papalampropoulou-Tsiridou
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC G1J 2G3, Canada,Graduate Program in Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
| | - Stephanie Shiers
- Center for Advanced Pain Studies and Department of Neuroscience, University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA
| | - Feng Wang
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC G1J 2G3, Canada
| | - Antoine G Godin
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC G1J 2G3, Canada,Graduate Program in Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada,Department of Psychiatry and Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
| | - Theodore J Price
- Center for Advanced Pain Studies and Department of Neuroscience, University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX 75080, USA
| | - Yves De Koninck
- Correspondence to: Yves De Koninck 2601 Chemin de la Canardière Québec G1J 2G3 Canada. E-mail:
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4
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De Vincenti AP, Alsina FC, Ferrero Restelli F, Hedman H, Ledda F, Paratcha G. Lrig1 and Lrig3 cooperate to control Ret receptor signaling, sensory axonal growth and epidermal innervation. Development 2021; 148:271159. [PMID: 34338291 DOI: 10.1242/dev.197020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 07/05/2021] [Indexed: 11/20/2022]
Abstract
Negative feedback loops represent a regulatory mechanism that guarantees that signaling thresholds are compatible with a physiological response. Previously, we established that Lrig1 acts through this mechanism to inhibit Ret activity. However, it is unclear whether other Lrig family members play similar roles. Here, we show that Lrig1 and Lrig3 are co-expressed in Ret-positive mouse dorsal root ganglion (DRG) neurons. Lrig3, like Lrig1, interacts with Ret and inhibits GDNF/Ret signaling. Treatment of DRG neurons with GDNF ligands induces a significant increase in the expression of Lrig1 and Lrig3. Our findings show that, whereas a single deletion of either Lrig1 or Lrig3 fails to promote Ret-mediated axonal growth, haploinsufficiency of Lrig1 in Lrig3 mutants significantly potentiates Ret signaling and axonal growth of DRG neurons in response to GDNF ligands. We observe that Lrig1 and Lrig3 act redundantly to ensure proper cutaneous innervation of nonpeptidergic axons and behavioral sensitivity to cold, which correlates with a significant increase in the expression of the cold-responsive channel TrpA1. Together, our findings provide insights into the in vivo functions through which Lrig genes control morphology, connectivity and function in sensory neurons.
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Affiliation(s)
- Ana Paula De Vincenti
- Laboratorio de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias (IBCN)-CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, CP1121, Argentina
| | - Fernando C Alsina
- Laboratorio de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias (IBCN)-CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, CP1121, Argentina
| | - Facundo Ferrero Restelli
- Laboratorio de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias (IBCN)-CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, CP1121, Argentina
| | - Håkan Hedman
- Oncology Research Laboratory, Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
| | - Fernanda Ledda
- Laboratorio de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias (IBCN)-CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, CP1121, Argentina.,Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Buenos Aires, C1405, Argentina
| | - Gustavo Paratcha
- Laboratorio de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias (IBCN)-CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, CP1121, Argentina
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5
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The evolution and multi-molecular properties of NF1 cutaneous neurofibromas originating from C-fiber sensory endings and terminal Schwann cells at normal sites of sensory terminations in the skin. PLoS One 2019; 14:e0216527. [PMID: 31107888 PMCID: PMC6527217 DOI: 10.1371/journal.pone.0216527] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 04/24/2019] [Indexed: 12/30/2022] Open
Abstract
In addition to large plexiform neurofibromas (pNF), NF1 patients are frequently disfigured by cutaneous neurofibromas (cNF) and are often afflicted with chronic pain and itch even from seemingly normal skin areas. Both pNFs and cNF consist primarily of benign hyperproliferating nonmyelinating Schwann cells (nSC). While pNF clearly arise within deep nerves and plexuses, the role of cutaneous innervation in the origin of cNF and in chronic itch and pain is unknown. First, we conducted a comprehensive, multi-molecular, immunofluorescence (IF) analyses on 3mm punch biopsies from three separate locations in normal appearing, cNF-free skin in 19 NF1 patients and skin of 16 normal subjects. At least one biopsy in 17 NF1 patients had previously undescribed micro-lesions consisting of a small, dense cluster of nonpeptidergic C-fiber endings and the affiliated nSC consistently adjoining adnexal structures—dermal papillae, hair follicles, sweat glands, sweat ducts, and arterioles—where C-fiber endings normally terminate. Similar micro-lesions were detected in hind paw skin of mice with conditionally-induced SC Nf1-/- mutations. Hypothesizing that these microlesions were pre-cNF origins of cNF, we subsequently analyzed numerous overt, small cNF (s-cNF, 3–6 mm) and discovered that each had an adnexal structure at the epicenter of vastly increased nonpeptidergic C-fiber terminals, accompanied by excessive nSC. The IF and functional genomics assays indicated that neurturin (NTRN) and artemin (ARTN) signaling through cRET kinase and GFRα2 and GFRα3 co-receptors on the aberrant C-fiber endings and nSC may mutually promote the onset of pre-cNF and their evolution to s-cNF. Moreover, TrpA1 and TrpV1 receptors may, respectively, mediate symptoms of chronic itch and pain. These newly discovered molecular characteristics might be targeted to suppress the development of cNF and to treat chronic itch and pain symptoms in NF1 patients.
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6
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Ishida K, Saito T, Mitsui T. In vitro formation of the Merkel cell-neurite complex in embryonic mouse whiskers using organotypic co-cultures. Dev Growth Differ 2018; 60:291-299. [PMID: 29785739 DOI: 10.1111/dgd.12535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 03/26/2018] [Accepted: 04/09/2018] [Indexed: 12/24/2022]
Abstract
A Merkel cell-neurite complex is a touch receptor composed of specialized epithelial cells named Merkel cells and peripheral sensory nerves in the skin. Merkel cells are found in touch-sensitive skin components including whisker follicles. The nerve fibers that innervate Merkel cells of a whisker follicle extend from the maxillary branch of the trigeminal ganglion. Whiskers as a sensory organ attribute to the complicated architecture of the Merkel cell-neurite complex, and therefore it is intriguing how the structure is formed. However, observing the dynamic process of the formation of a Merkel cell-neurite complex in whiskers during embryonic development is still difficult. In this study, we tried to develop an organotypic co-culture method of a whisker pad and a trigeminal ganglion explant to form the Merkel cell-neurite complex in vitro. We initially developed two distinct culture methods of a single whisker row and a trigeminal ganglion explant, and then combined them. By dissecting and cultivating a single row from a whisker pad, the morphogenesis of whisker follicles could be observed under a microscope. After the co-cultivation of the whisker row with a trigeminal ganglion explant, a Merkel cell-neurite complex composed of Merkel cells, which were positive for both cytokeratin 8 and SOX2, Neurofilament-H-positive trigeminal nerve fibers and Schwann cells expressing Nestin, SOX2 and SOX10 was observed via immunohistochemical analyses. These results suggest that the process for the formation of a Merkel cell-neurite complex can be observed under a microscope using our organotypic co-culture method.
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Affiliation(s)
- Kentaro Ishida
- Department of Physics and Mathematics, College of Science and Engineering, Aoyama Gakuin University, Kanagawa, Japan.,Department of Developmental Biology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Tetsuichiro Saito
- Department of Developmental Biology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Toshiyuki Mitsui
- Department of Physics and Mathematics, College of Science and Engineering, Aoyama Gakuin University, Kanagawa, Japan
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7
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Rosich K, Hanna BF, Ibrahim RK, Hellenbrand DJ, Hanna A. The Effects of Glial Cell Line-Derived Neurotrophic Factor after Spinal Cord Injury. J Neurotrauma 2017; 34:3311-3325. [DOI: 10.1089/neu.2017.5175] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Konstantin Rosich
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin
| | - Bishoy F. Hanna
- Department of Neurological Surgery, Ross University School of Medicine, Dominica, West Indies
| | - Rami K. Ibrahim
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin
| | - Daniel J. Hellenbrand
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin
| | - Amgad Hanna
- Department of Neurological Surgery, University of Wisconsin, Madison, Wisconsin
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8
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Ibáñez CF, Andressoo JO. Biology of GDNF and its receptors — Relevance for disorders of the central nervous system. Neurobiol Dis 2017; 97:80-89. [DOI: 10.1016/j.nbd.2016.01.021] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/14/2016] [Accepted: 01/25/2016] [Indexed: 01/15/2023] Open
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9
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Safavi S, Järnum S, Vannas C, Udhane S, Jonasson E, Tomic TT, Grundevik P, Fagman H, Hansson M, Kalender Z, Jauhiainen A, Dolatabadi S, Stratford EW, Myklebost O, Eriksson M, Stenman G, Schneider-Stock R, Ståhlberg A, Åman P. HSP90 inhibition blocks ERBB3 and RET phosphorylation in myxoid/round cell liposarcoma and causes massive cell death in vitro and in vivo. Oncotarget 2016; 7:433-45. [PMID: 26595521 PMCID: PMC4808009 DOI: 10.18632/oncotarget.6336] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 10/30/2015] [Indexed: 12/23/2022] Open
Abstract
Myxoid sarcoma (MLS) is one of the most common types of malignant soft tissue tumors. MLS is characterized by the FUS-DDIT3 or EWSR1-DDIT3 fusion oncogenes that encode abnormal transcription factors. The receptor tyrosine kinase (RTK) encoding RET was previously identified as a putative downstream target gene to FUS-DDIT3 and here we show that cultured MLS cells expressed phosphorylated RET together with its ligand Persephin. Treatment with RET specific kinase inhibitor Vandetanib failed to reduce RET phosphorylation and inhibit cell growth, suggesting that other RTKs may phosphorylate RET. A screening pointed out EGFR and ERBB3 as the strongest expressed phosphorylated RTKs in MLS cells. We show that ERBB3 formed nuclear and cytoplasmic complexes with RET and both RTKs were previously reported to form complexes with EGFR. The formation of RTK hetero complexes could explain the observed Vandetanib resistence in MLS. EGFR and ERBB3 are clients of HSP90 that help complex formation and RTK activation. Treatment of cultured MLS cells with HSP90 inhibitor 17-DMAG, caused loss of RET and ERBB3 phosphorylation and lead to rapid cell death. Treatment of MLS xenograft carrying Nude mice resulted in massive necrosis, rupture of capillaries and hemorrhages in tumor tissues. We conclude that complex formation between RET and other RTKs may cause RTK inhibitor resistance. HSP90 inhibitors can overcome this resistance and are thus promising drugs for treatment of MLS/RCLS.
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Affiliation(s)
- Setareh Safavi
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Sofia Järnum
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Christoffer Vannas
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Sameer Udhane
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Emma Jonasson
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Tajana Tesan Tomic
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Pernilla Grundevik
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Fagman
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Magnus Hansson
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Zeynep Kalender
- Mathematical Statistics, Mathematical Sciences, Chalmers University of Technology and the University of Gothenburg, Göteborg, Sweden
| | - Alexandra Jauhiainen
- Mathematical Statistics, Mathematical Sciences, Chalmers University of Technology and the University of Gothenburg, Göteborg, Sweden
| | - Soheila Dolatabadi
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Eva Wessel Stratford
- Department of Tumour Biology, The Norwegian Radium Hospital, Oslo University Hospital, Nydalen, Oslo, Norway
| | - Ola Myklebost
- Department of Tumour Biology, The Norwegian Radium Hospital, Oslo University Hospital, Nydalen, Oslo, Norway
| | - Mikael Eriksson
- Department of Oncology, Lund University Hospital, Lund, Sweden
| | - Göran Stenman
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Regine Schneider-Stock
- Experimental Tumor Pathology, Institute of Pathology, University of Erlangen-Nürnberg, Ulmenweg Erlangen, Germany
| | - Anders Ståhlberg
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Pierre Åman
- Sahlgrenska Cancer Center, Institute of Biomedicine, Department of Pathology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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10
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Bolon B, Jing S, Asuncion F, Scully S, Pisegna M, Van GY, Hu Z, Yu YB, Min H, Wild K, Rosenfeld RD, Tarpley J, Carnahan J, Duryea D, Hill D, Kaufman S, Yan XQ, Juan T, Christensen K, McCabe J, Simonet WS. The Candidate Neuroprotective Agent Artemin Induces Autonomic Neural Dysplasia without Preventing Peripheral Nerve Dysfunction. Toxicol Pathol 2016; 32:275-94. [PMID: 15204970 DOI: 10.1080/01926230490431475] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Artemin (ART) signals through the GFR α—3/RET receptor complex to support sympathetic neuron development. Here we show that ART also influences autonomic elements in adrenal medulla and enteric and pelvic ganglia. Transgenic mice over-expressing Art throughout development exhibited systemic autonomic neural lesions including fusion of adrenal medullae with adjacent paraganglia, adrenal medullary dysplasia, and marked enlargement of sympathetic (superior cervical and sympathetic chain ganglia) and parasympathetic (enteric, pelvic) ganglia. Changes began by gestational day 12.5 and formed progressively larger masses during adulthood. Art supplementation in wild type adult mice by administering recombinant protein or an Art-bearing retroviral vector resulted in hyperplasia or neuronal metaplasia at the adrenal corticomedullary junction. Expression data revealed that Gfr α—3 is expressed during development in the adrenal medulla, sensory and autonomic ganglia and their projections, while Art is found in contiguous mesenchymal domains (especially skeleton) and in certain nerves. Intrathecal Art therapy did not reduce hypalgesia in rats following nerve ligation. These data (1) confirm that ART acts as a differentiation factor for autonomic (chiefly sympathoadrenal but also parasympathetic) neurons, (2) suggest a role for ART overexpression in the genesis of pheochromocytomas and paragangliomas, and (3) indicate that ART is not a suitable therapy for peripheral neuropathy.
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Affiliation(s)
- Brad Bolon
- Department of Pathology, Amgen Inc., Thousand Oaks, California 91320-1799, USA
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11
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Xu P, Rosen KM, Hedstrom K, Rey O, Guha S, Hart C, Corfas G. Nerve injury induces glial cell line-derived neurotrophic factor (GDNF) expression in Schwann cells through purinergic signaling and the PKC-PKD pathway. Glia 2013; 61:1029-40. [PMID: 23553603 DOI: 10.1002/glia.22491] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 02/06/2013] [Indexed: 12/22/2022]
Abstract
Upon peripheral nerve injury, specific molecular events, including increases in the expression of selected neurotrophic factors, are initiated to prepare the tissue for regeneration. However, the mechanisms underlying these events and the nature of the cells involved are poorly understood. We used the injury-induced upregulation of glial cell-derived neurotrophic factor (GDNF) expression as a tool to gain insights into these processes. We found that both myelinating and nonmyelinating Schwann cells are responsible for the dramatic increase in GDNF expression after injury. We also demonstrate that the GDNF upregulation is mediated by a signaling cascade involving activation of Schwann cell purinergic receptors, followed by protein kinase C signaling which activates protein kinase D (PKD), which leads to increased GDNF transcription. Given the potent effects of GDNF on survival and repair of injured peripheral neurons, we propose that targeting these pathways may yield therapeutic tools to treat peripheral nerve injury and neuropathies.
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Affiliation(s)
- Pin Xu
- F.M. Kirby Neurobiology Center, Children's Hospital Boston, Boston, MA, USA
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12
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Atopic keratinocytes induce increased neurite outgrowth in a coculture model of porcine dorsal root ganglia neurons and human skin cells. J Invest Dermatol 2012; 132:1892-900. [PMID: 22418869 DOI: 10.1038/jid.2012.44] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Skin of patients suffering from atopic eczema displays a higher epidermal nerve fiber density, associated with neurogenic inflammation and pruritus. Using an in vitro coculture system, allowing a spatially compartmented culture of somata from porcine dorsal root ganglion neurons and human primary skin cells, we investigated the influence of dermal fibroblasts and keratinocytes on neurite outgrowth. In comparison with dermal fibroblasts, keratinocytes induced more branched and less calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers. By adding neutralizing antibodies, we showed that nerve growth factor (NGF) and glial cell-line-derived neurotrophic factor (GDNF) are pivotal neurotrophic factors of skin cell-induced neurite outgrowth. Keratinocytes and dermal fibroblasts secreted different ratios of neurotrophic factors, influencing morphology and CGRP immunoreactivity of neurites. To investigate changes of the peripheral nervous system in the pathogenesis of atopic eczema in vitro, we analyzed neurite outgrowth mediated by atopic skin cells. Atopic keratinocytes produced elevated levels of NGF and mediated an increased outgrowth of CGRP-positive sensory fibers. Our results demonstrate the impact of dermal fibroblasts and keratinocytes on skin innervation and emphasize the role of keratinocytes as key players of hyperinnervation in atopic eczema.
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13
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Vellani V, Prandini M, Giacomoni C, Pavesi G, Ravegnani L, Magherini PC. Functional endothelin receptors are selectively expressed in isolectin B4-negative sensory neurons and are upregulated in isolectin B4-positive neurons by neurturin and glia-derived neurotropic factor. Brain Res 2011; 1381:31-7. [DOI: 10.1016/j.brainres.2011.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 12/01/2010] [Accepted: 01/08/2011] [Indexed: 12/01/2022]
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14
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Reed-Geaghan EG, Maricich SM. Peripheral somatosensation: a touch of genetics. Curr Opin Genet Dev 2011; 21:240-8. [PMID: 21277195 DOI: 10.1016/j.gde.2010.12.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 12/21/2010] [Indexed: 11/26/2022]
Abstract
The somatosensory system processes information that organisms 'feel': joint position, muscle stretch, pain, pressure, temperature, and touch. The system is composed of a diverse array of peripheral nerve endings specialized to detect these sensory modalities. Several recent discoveries have shed light on the genetic pathways that control specification and differentiation of these neurons, how they accurately innervate their central and peripheral targets, and the molecules that enable them to detect mechanical stimuli. Here, we review the cadre of genes that control these processes, focusing on mechanosensitive neurons and support cells of the skin that mediate different aspects of the sense of touch.
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Affiliation(s)
- Erin G Reed-Geaghan
- Department of Pediatrics, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, United States
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15
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Mosconi T, Gruber T. Immunohistochemical comparison of whisker pad cutaneous innervation in Swiss Webster and hairless mice. Somatosens Mot Res 2010; 27:149-73. [PMID: 20961209 DOI: 10.3109/08990220.2010.513597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
To establish the mouse mutant, hairless (Hr), as a useful model for future analyses of target-ending interactions, we assessed the cutaneous innervation in the whisker pad after loss of primary hair targets. Postnatal (P) development of fur in Hr begins similarly to that of "normal" Swiss Webster (SW) mice. Around P10, hairs are shed and the follicles rendered permanently incompetent. Hair loss progresses rostrocaudally until the entire skin is denuded. Substantial alterations in the distribution and density of sensory and autonomic endings in the mystacial pad vibrissal and intervibrissal fur innervation were discovered. Pilo-neural complexes innervating fur hairs were dismantled in Hr. Epidermal innervation in SW was rich; only a few endings expressed growth-associated protein-43 kdal (GAP), suggesting limited changes in axonal elongation. Innervation in Hr formed a dense layer passing upward through the thickened epidermis, with substantial increases among all types of endings. Vibrissal follicle-sinus complexes were also hyperinnervated. Endings in Hr vibrissae and fur were strongly GAP-positive, suggesting reorganization of innervation. Dermal and vascular autonomic innervation in both strains co-localized tyrosine hydroxylase and neuropeptide Y, but only in Hr did neuropeptide Y co-localize calcitonin gene-related peptide (CGRP) and express GAP immunolabeling. Stereological quantitation of trigeminal ganglia revealed no differences in neuron number between Hr and SW, although there were small increases in cell volume in Hr trigeminal ganglion cells. These results suggested that a form of collateral sprouting was active in Hr mystacial pads, not in response to local injury, but as a result of loss of primary target tissues.
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Affiliation(s)
- Tony Mosconi
- Department of Physical Therapy Education, Western University of Health Sciences, Pomona, CA 91766, USA.
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16
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Honma Y, Kawano M, Kohsaka S, Ogawa M. Axonal projections of mechanoreceptive dorsal root ganglion neurons depend on Ret. Development 2010; 137:2319-28. [DOI: 10.1242/dev.046995] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Establishment of connectivity between peripheral and central organs is essential for sensory processing by dorsal root ganglion (DRG) neurons. Using Ret as a marker for mechanoreceptive DRG neurons, we show that both central and peripheral projections of mechanoreceptive neurons are severely impaired in the absence of Ret. Death of DRG neurons in Ret-deficient mice can be rescued by eliminating Bax, although their projections remain disrupted. Furthermore, ectopic expression of the Ret ligand neurturin, but not Gdnf, in the spinal cord induces aberrant projection of mechanoreceptive afferents. Our results demonstrate that Ret expression in DRG neurons is crucial for the neurturin-mediated formation of precise axonal projections in the central nervous system.
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Affiliation(s)
- Yutaka Honma
- Ogawa Research Unit, Brain Science Institute, RIKEN, Saitama 351-0198, Japan
| | - Masako Kawano
- Ogawa Research Unit, Brain Science Institute, RIKEN, Saitama 351-0198, Japan
| | - Shinichi Kohsaka
- Department of Neurochemistry, National Institute of Neuroscience, Kodaira, Tokyo 187-8502, Japan
| | - Masaharu Ogawa
- Ogawa Research Unit, Brain Science Institute, RIKEN, Saitama 351-0198, Japan
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17
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Bourane S, Garces A, Venteo S, Pattyn A, Hubert T, Fichard A, Puech S, Boukhaddaoui H, Baudet C, Takahashi S, Valmier J, Carroll P. Low-threshold mechanoreceptor subtypes selectively express MafA and are specified by Ret signaling. Neuron 2010; 64:857-70. [PMID: 20064392 DOI: 10.1016/j.neuron.2009.12.004] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2009] [Indexed: 02/01/2023]
Abstract
Low-threshold mechanoreceptor neurons (LTMs) of the dorsal root ganglia (DRG) are essential for touch sensation. They form highly specialized terminations in the skin and display stereotyped projections in the spinal cord. Functionally defined LTMs depend on neurotrophin signaling for their postnatal survival and functioning, but how these neurons arise during development is unknown. Here, we show that specific types of LTMs can be identified shortly after DRG genesis by unique expression of the MafA transcription factor, the Ret receptor and coreceptor GFRalpha2, and find that their specification is Ngn2 dependent. In mice lacking Ret, these LTMs display early differentiation defects, as revealed by reduced MafA expression, and at later stages their central and peripheral projections are compromised. Moreover, in MafA mutants, a discrete subset of LTMs display altered expression of neurotrophic factor receptors. Our results provide evidence that genetic interactions involving Ret and MafA progressively promote the differentiation and diversification of LTMs.
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18
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BDNF is essentially required for the early postnatal survival of nociceptors. Dev Biol 2010; 339:465-76. [PMID: 20067784 DOI: 10.1016/j.ydbio.2010.01.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 12/13/2009] [Accepted: 01/05/2010] [Indexed: 01/19/2023]
Abstract
Neurotrophins promote the survival of specific types of neurons during development and ensure proper maintenance and function of mature responsive neurons. Significant effects of BDNF (Brain-Derived Neurotrophic Factor) on pain physiology have been reported but the contribution of this neurotrophin to the development of nociceptors has not been investigated. We present evidence that BDNF is required for the survival of a significant fraction of peptidergic and non-peptidergic nociceptors in dorsal root ganglia (DRG) postnatally. Bdnf homozygous mutant mice lose approximately half of all nociceptive neurons during the first 2 weeks of life and adult heterozygotes exhibit hypoalgesia and a loss of 25% of all nociceptive neurons. Our in vitro analyses indicate that BDNF-dependent nociceptive neurons also respond to NGF and GDNF. Expression analyses at perinatal times indicate that BDNF is predominantly produced within sensory ganglia and is more abundant than skin-derived NGF or GDNF. Function-blocking studies with BDNF specific antibodies in vitro or cultures of BDNF-deficient sensory neurons suggest that BDNF acts in an autocrine/paracrine way to promote the early postnatal survival of nociceptors that are also responsive to NGF and GDNF. Altogether, the data demonstrate an essential requirement for BDNF in the early postnatal survival of nociceptive neurons.
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19
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Macrophage stimulating protein is a neurotrophic factor for a sub-population of adult nociceptive sensory neurons. Mol Cell Neurosci 2009; 41:175-85. [DOI: 10.1016/j.mcn.2009.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 02/18/2009] [Accepted: 02/19/2009] [Indexed: 12/31/2022] Open
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20
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Luo W, Wickramasinghe SR, Savitt JM, Griffin JW, Dawson TM, Ginty DD. A hierarchical NGF signaling cascade controls Ret-dependent and Ret-independent events during development of nonpeptidergic DRG neurons. Neuron 2007; 54:739-54. [PMID: 17553423 DOI: 10.1016/j.neuron.2007.04.027] [Citation(s) in RCA: 189] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 04/17/2007] [Accepted: 04/26/2007] [Indexed: 11/20/2022]
Abstract
NGF controls survival, differentiation, and target innervation of both peptidergic and nonpeptidergic DRG sensory neurons. The common receptor for GDNF family ligands, Ret, is highly expressed in nonpeptidergic neurons, but its function during development of these neurons is unclear. Here, we show that expression of Ret and its coreceptors GFRalpha1 and GFRalpha2 is dependent on NGF. GFR/Ret signaling, in turn, autoregulates expression of both GFRalpha1 and GFRalpha2 and promotes expression of TrpA1, MrgA1, MrgA3, and MrgB4, acquisition of normal neuronal size, axonal innervation of the epidermis, and postnatal extinction of the NGF receptor TrkA. Moreover, NGF controls expression of several other genes characteristic of nonpeptidergic neurons, such as TrpC3, TrpM8, MrgD, and the transcription factor Runx1, via a Ret-independent signaling pathway. These findings support a model in which NGF controls maturation of nonpeptidergic DRG neurons through a combination of GFR/Ret-dependent and -independent signaling pathways.
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MESH Headings
- Animals
- Cell Differentiation/physiology
- Ganglia, Spinal/cytology
- Ganglia, Spinal/embryology
- Ganglia, Spinal/metabolism
- Gene Expression Regulation, Developmental/physiology
- Glial Cell Line-Derived Neurotrophic Factor Receptors/metabolism
- Ion Channels/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Nerve Growth Factor/metabolism
- Neurons, Afferent/cytology
- Neurons, Afferent/metabolism
- Nociceptors/cytology
- Nociceptors/embryology
- Nociceptors/metabolism
- Organ Culture Techniques
- Proto-Oncogene Proteins c-ret/metabolism
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction/physiology
- Transcription Factors/metabolism
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Affiliation(s)
- Wenqin Luo
- The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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21
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Igarashi Y, Aita M, Suzuki A, Nandasena T, Kawano Y, Nozawa-Inoue K, Maeda T. Involvement of GDNF and its receptors in the maturation of the periodontal Ruffini endings. Neurosci Lett 2007; 412:222-6. [PMID: 17178438 DOI: 10.1016/j.neulet.2006.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 10/04/2006] [Accepted: 11/03/2006] [Indexed: 11/26/2022]
Abstract
Our recent study revealed an intense immunoreaction for GDNF and its receptors in the Ruffini endings, primary mechanoreceptors in the periodontal ligament, of young rats. However, no information is available for the expression of GDNF and its receptors during their development. The present study aimed to reveal postnatal changes in the immuno-expression of GDNF, GFRalpha1 and RET in the periodontal Ruffini endings of the rat incisors by double immunofluorescent staining. At postnatal day 3 (PO 3d), no structure with GDNF-, GFRalpha1-, or RET-immunoreaction existed in the periodontal ligament. The PGP 9.5-positive nerve fibers without GDNF- and RET-immunoreaction displayed a dendritic fashion at PO 1w, with a GFRalpha1-reaction found around these nerves. At PO 2w, GDNF-positive terminal Schwann cells occurred near the thick and dendritic axons, a part of which showed a RET-reaction, with no reactive cells near the thin nerves. The terminal Schwann cells became positive for GFRalpha1, but lacked RET-immunoreaction. At PO 3w, when the formation of the periodontal Ruffini endings had proceeded, GDNF-positive terminal Schwann cells began to increase in number. This stage-specific immuno-expression pattern suggests that GDNF is a key molecule for the maturation and maintenance of the periodontal Ruffini endings.
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Affiliation(s)
- Yasushi Igarashi
- Division of Oral Anatomy, Niigata University Graduate School of Medical and Dental Sciences, 2-5274 Gakkocho-dori, Niigata 951-8514, Japan
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22
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Airaksinen MS, Holm L, Hätinen T. Evolution of the GDNF family ligands and receptors. BRAIN, BEHAVIOR AND EVOLUTION 2006; 68:181-90. [PMID: 16912471 DOI: 10.1159/000094087] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Indexed: 12/25/2022]
Abstract
Four different ligand-receptor binding pairs of the GDNF (glial cell line-derived neurotrophic factor) family exist in mammals, and they all signal via the transmembrane RET receptor tyrosine kinase. In addition, GRAL (GDNF Receptor Alpha-Like) protein of unknown function and Gas1 (growth arrest specific 1) have GDNF family receptor (GFR)-like domains. Orthologs of the four GFRalpha receptors, GRAL and Gas1 are present in all vertebrate classes. In contrast, although bony fishes have orthologs of all four GDNF family ligands (GFLs), one of the ligands, neurturin, is absent in clawed frog and another, persephin, is absent in the chicken genome. Frog GFRalpha2 has selectively evolved possibly to accommodate GDNF as a ligand. The key role of GDNF and its receptor GFRalpha1 in enteric nervous system development is conserved from zebrafish to humans. The role of neurturin, signaling via GFRalpha2, for parasympathetic neuron development is conserved between chicken and mice. The role of artemin and persephin that signal via GFRalpha3 and GFRalpha4, respectively, is unknown in non-mammals. The presence of RET- and GFR-like genes in insects suggests that a ProtoGFR and a ProtoRET arose early in the evolution of bilaterian animals, but when the ProtoGFL diverged from existing transforming growth factor (TGFbeta)-like proteins remains unclear. The four GFLs and GFRalphas were presumably generated by genome duplications at the origin of vertebrates. Loss of neurturin in frog and persephin in chicken suggests functional redundancy in early tetrapods. Functions of non-mammalian GFLs and prechordate RET and GFR-like proteins remain to be explored.
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23
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Aita M, Kawano Y, Maeda T. Expression of GDNF and its receptors in the periodontal mechanoreceptor. Neurosci Lett 2006; 400:25-9. [PMID: 16513266 DOI: 10.1016/j.neulet.2006.02.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 02/03/2006] [Accepted: 02/06/2006] [Indexed: 11/25/2022]
Abstract
Our previous studies have revealed the involvement of signaling pathways of BDNF and NT-4/5 via TrkB in the development, regeneration, survival and maintenance of the Ruffini endings, primary mechanoreceptors in the periodontal ligament. However, the involvement of other neurotrophins remains unclear. The present study examined the expression of GDNF, GFRalpha1, and RET in the incisor periodontal ligament and trigeminal ganglion of young rats by RT-PCR and immunocytochemistry. All these mRNAs were detected in both tissues by RT-PCR. These immunoreactions were found in the terminal Schwann cells associated with the periodontal Ruffini endings, as confirmed by histochemistry for non-specific cholinesterase activity. Their axonal branches showed GFRalpha1- and RET-immunoreactions but lacked GDNF-immunoreactivity. In the trigeminal ganglion, about 30% of the neurons were immunoreactive to GFRalpha1 and RET. Averages of cross-sectional areas of their positive neurons demonstrated that they could mainly be categorized as medium-sized neurons. GDNF-immunoreaction was restricted to the satellite cells and not in trigeminal ganglion neurons. These findings indicate that GDNF mediates trophic effects on the survival and target innervation of the periodontal Ruffini endings via GFRalpha1 and RET.
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Affiliation(s)
- Megumi Aita
- Division of Oral Anatomy, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
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24
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Anand U, Otto WR, Casula MA, Day NC, Davis JB, Bountra C, Birch R, Anand P. The effect of neurotrophic factors on morphology, TRPV1 expression and capsaicin responses of cultured human DRG sensory neurons. Neurosci Lett 2006; 399:51-6. [PMID: 16481104 DOI: 10.1016/j.neulet.2006.01.046] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 01/15/2006] [Accepted: 01/20/2006] [Indexed: 11/23/2022]
Abstract
We have studied the effect of key neurotrophic factors (NTFs) on morphology, levels of the vanilloid receptor-1 (TRPV1) and responses to capsaicin in adult human sensory neurons in vitro. Avulsed dorsal root ganglia (DRG, n = 5) were cultured with or without a combination of nerve growth factor (NGF), glial cell (line)-derived growth factor (GDNF) and neurotrophin3 (NT3) for 5 days. In the absence of NTFs, the diameter of neurons ranged from 20 to 100 microm (mean 42 +/- 4 microm). Adding NTFs caused a significant increase in neuronal sizes, up to 120 microm (mean diameter 62 +/- 5 microm, P < 0.01, t-test), an overall 35% increase of TRPV1-positive neurons (P < 0.003), and notably of large TRPV1-positive neurons > 80 microm (P < 0.05). Responses to capsaicin were significantly enhanced with calcium ratiometry (P < 0.0001). Short duration (1h) exposure of dissociated sensory neurons to NTFs increased numbers of TRPV1-positive neurons, but not of TRPV3, Nav 1.8 and IK1 and the morphological size-distribution remained similar to intact post-mortem DRG neurons. NTFs thus increase size, elevate TRPV1 levels and enhance capsaicin responses in cultured human DRG neurons; these changes may relate to pathophysiology in disease states, and provide an in vitro model to study novel analgesics.
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Affiliation(s)
- U Anand
- Peripheral Neuropathy Unit, Imperial College, Area A, Ground Floor, Hammersmith Hospital, Du Cane Road, London W12 ONN, UK
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25
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Quartu M, Serra MP, Mascia F, Boi M, Lai ML, Spano A, Del Fiacco M. GDNF family ligand receptor components Ret and GFRalpha-1 in the human trigeminal ganglion and sensory nuclei. Brain Res Bull 2006; 69:393-403. [PMID: 16624671 DOI: 10.1016/j.brainresbull.2006.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Revised: 12/21/2005] [Accepted: 02/09/2006] [Indexed: 01/10/2023]
Abstract
The occurrence of Ret and GFRalpha-1 receptors is shown by immunohistochemistry in the human trigeminal sensory system at pre-, postnatal and adult age. Receptor-labeled neurons occur in both trigeminal ganglion and mesencephalic nucleus. In adult trigeminal ganglion, about 75% of Ret- and 65% of GFRalpha-1-labeled neurons are small- and medium-sized. The proportion of Ret+ and GFRalpha-1+ trigeminal ganglion neurons in the adult is about 25 and 60%, respectively. The majority of Ret+ are double labeled for GFRalpha-1 and glial cell line-derived neurotrophic factor (GDNF). Most of the GFRalpha-1+ cells contain GDNF and about 50% of them contain Ret. Triple labeling shows many Ret+/GDNF+/GFRalpha-1+ neurons, but also a number of Ret-/GDNF+/GFRalpha-1+ and Ret+/GDNF-/GFRalpha-1+ cells. Both Ret+ and GFRalpha-1+ neuronal subpopulations overlap with that containing calcitonin gene-related peptide. Ret+ pericellular basket-like nerve fibers occur in the adult trigeminal ganglion. Centrally, immunoreactivity is restricted to the spinal nucleus pars caudalis and pars interpolaris and to the mesencephalic nucleus. In adult specimens, Ret+ nerve fibers and puncta gather in the inner substantia gelatinosa. Ret+ neurons occur in the spinal nucleus and are more frequent in newborn than in adult subjects. Central GFRalpha-1+-labeled neurons and punctate elements are sparse. These findings support the involvement of GDNF and possibly other cognate ligands in the trophism of human trigeminal primary sensory neurons from prenatal life to adulthood, indicating a selective commitment to cells devoted to protopathic and proprioceptive sensory transmission. They also support the possibility that receptor molecules other than Ret could be active in transducing the ligand signal.
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Affiliation(s)
- Marina Quartu
- Department of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy
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26
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Erzurumlu RS, Chen ZF, Jacquin MF. Molecular determinants of the face map development in the trigeminal brainstem. THE ANATOMICAL RECORD. PART A, DISCOVERIES IN MOLECULAR, CELLULAR, AND EVOLUTIONARY BIOLOGY 2006; 288:121-34. [PMID: 16432893 PMCID: PMC3556733 DOI: 10.1002/ar.a.20285] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The perception of external sensory information by the brain requires highly ordered synaptic connectivity between peripheral sensory neurons and their targets in the central nervous system. Since the discovery of the whisker-related barrel patterns in the mouse cortex, the trigeminal system has become a favorite model for study of how its connectivity and somatotopic maps are established during development. The trigeminal brainstem nuclei are the first CNS regions where whisker-specific neural patterns are set up by the trigeminal afferents that innervate the whiskers. In particular, barrelette patterns in the principal sensory nucleus of the trigeminal nerve provide the template for similar patterns in the face representation areas of the thalamus and subsequently in the primary somatosensory cortex. Here, we describe and review studies of neurotrophins, multiple axon guidance molecules, transcription factors, and glutamate receptors during early development of trigeminal connections between the whiskers and the brainstem that lead to emergence of patterned face maps. Studies from our laboratories and others' showed that developing trigeminal ganglion cells and their axons depend on a variety of molecular signals that cooperatively direct them to proper peripheral and central targets and sculpt their synaptic terminal fields into patterns that replicate the organization of the whiskers on the muzzle. Similar mechanisms may also be used by trigeminothalamic and thalamocortical projections in establishing patterned neural modules upstream from the trigeminal brainstem.
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Affiliation(s)
- Reha S Erzurumlu
- Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112, USA.
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27
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Grelik C, Allard S, Ribeiro-da-Silva A. Changes in nociceptive sensory innervation in the epidermis of the rat lower lip skin in a model of neuropathic pain. Neurosci Lett 2005; 389:140-5. [PMID: 16139429 DOI: 10.1016/j.neulet.2005.07.056] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 06/18/2005] [Accepted: 07/20/2005] [Indexed: 12/21/2022]
Abstract
The epidermis is innervated by fine nerve endings that are important in the perception of nociceptive stimuli. However, their role in neuropathic pain is controversial. In this paper, changes in the innervation patterns of epidermal sensory afferent fibres in the rat lower lip have been studied following bilateral chronic constriction injury (CCI) of the mental nerve-a purely sensory branch of the trigeminal nerve. Sections of the lower lip were processed for immunocytochemistry using antibodies against Protein Gene Product (PGP) 9.5 and Calcitonin Gene-Related Peptide (CGRP) to identify the non-peptidergic and the peptidergic populations of nociceptive small diameter primary sensory afferent fibres. Peptidergic fibres co-localised both markers and the non-peptidergic fibres only stained for PGP 9.5 and not for CGRP. We quantified the total fibre length per 6000 microm(2) in the epidermis at several time points following CCI. Our data indicate that both fibre populations were significantly decreased at 2 weeks post-CCI, followed by fibre re-growth at levels above those seen in sham-operated animals at 4 weeks; however, this increase was only statistically significant for the non-peptidergic population. At 8 weeks post-CCI, the fibre lengths of both populations did not differ significantly from shams. This transient hyper-innervation of the epidermis by one subpopulation of nociceptive fibres coincided with the occurrence of spontaneous pain or dysesthetic sensations which we detected in a previous study in the same animal model. Therefore, we speculate that this transient hyper-innervation of the epidermis following injury could play a role in nociception in these animals.
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Affiliation(s)
- C Grelik
- Department of Pharmacology and Therapeutics, 3655 Prom. Sir-William-Osler, Montreal, Que., Canada H3G 1Y6
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28
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Enomoto H. Regulation of neural development by glial cell line-derived neurotrophic factor family ligands. Anat Sci Int 2005; 80:42-52. [PMID: 15794130 DOI: 10.1111/j.1447-073x.2005.00099.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) and its three relatives constitute a novel family of neurotrophic factors, the GDNF family ligands. These factors signal through a multicomponent receptor complex comprising a glycosylphosphatidylinositol-anchored cell surface molecule (GDNF family receptor (GFR) alpha) and RET tyrosine kinase, triggering the activation of multiple signaling pathways in responsive cells. Recent gene-targeting studies have demonstrated that GDNF family ligands are essential for the development of a diverse set of neuronal populations and we have now started to understand how these ligands uniquely regulate the formation and sculpting of the nervous system. Recent studies have also revealed interactions by multiple extracellular signals during neural development. The deciphering of GDNF family ligand signaling in neural cells promises to provide vital new insights into the development and pathology of the nervous system.
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Affiliation(s)
- Hideki Enomoto
- RIKEN Center for Developmental Biology, Kobe, Hyogo, Japan.
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Kvinnsland IH, Luukko K, Fristad I, Kettunen P, Jackson DL, Fjeld K, von Bartheld CS, Byers MR. Glial cell line-derived neurotrophic factor (GDNF) from adult rat tooth serves a distinct population of large-sized trigeminal neurons. Eur J Neurosci 2004; 19:2089-98. [PMID: 15090036 DOI: 10.1111/j.0953-816x.2004.03291.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) mediates trophic effects for specific classes of sensory neurons. The adult tooth pulp is a well-defined target of sensory trigeminal innervation. Here we investigated potential roles of GDNF in the regulation of adult trigeminal neurons and the dental pulp nerve supply of the rat maxillary first molar. Western blot analysis and radioactive 35S-UTP in situ hybridization revealed that GDNF in the dental pulp and its mRNAs were localized with Ngf in the coronal pulp periphery, in particular in the highly innervated subodontoblast layer. Retrograde neuronal transport of iodinated GDNF and Fluorogold (FG) from the dental pulp indicated that GDNF was transported in about one third of all the trigeminal dental neurons. Of the GDNF-labelled neurons, nearly all (97%) were large-sized (> or =35 microm in diameter). Analysis of FG-labelled neurons revealed that, of the trigeminal neurons supporting the adult dental pulp, approximately 20% were small-sized, lacked isolectin B4 binding and did not transport GDNF. Of the large-sized dental trigeminal neurons approximately 40% transported GDNF. About 90% of the GDNF-accumulating neurons were negative for the high-temperature nociceptive marker VRL-1. Our results show that a subclass of large adult trigeminal neurons are potentially dependent on dental pulp-derived GDNF while small dental trigeminal neurons seems not to require GDNF. This suggests that GDNF may function as a neurotrophic factor for subsets of nerves in the tooth, which apparently mediate mechanosensitive stimuli. As in dorsal root ganglia both small- and large-sized neurons are known to be GDNF-dependent; these data provide molecular evidence that the sensory supply in the adult tooth differs, in some aspects, from the cutaneous sensory system.
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Affiliation(s)
- Inger Hals Kvinnsland
- Department of Anatomy and Cell Biology, University of Bergen, Jonas Liesvei 91, N-5009 Bergen, Norway.
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30
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Paveliev M, Airaksinen MS, Saarma M. GDNF family ligands activate multiple events during axonal growth in mature sensory neurons. Mol Cell Neurosci 2004; 25:453-9. [PMID: 15033173 DOI: 10.1016/j.mcn.2003.11.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2003] [Revised: 10/22/2003] [Accepted: 11/03/2003] [Indexed: 10/26/2022] Open
Abstract
The need for medical treatment of neuronal trauma motivates the search for new agents to stimulate posttraumatic axonal regrowth, as well as improving understanding of signaling cascades regulating this process. GDNF stimulates axonal regeneration in the peripheral nervous system, but little is known about the mechanism of this effect. Neurturin, artemin and persephin are homologs of GDNF, and their impact on axonal regeneration in adults has not been studied yet. Here we show that neurturin, artemin and GDNF, but not persephin, promote axonal initiation in cultured dorsal root ganglion neurons from young adult mice. This effect requires Src-family kinase activity as it was blocked by SU6656. In neurons from GFRalpha2-deficient mice, neurturin does not significantly promote axonal initiation. We also show that neurturin and GDNF induce extensive lamellipodia formation on neuronal somata and growth cones. GDNF, when applied after the time of axonal initiation in culture, also promotes axonal elongation.
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Affiliation(s)
- Mikhail Paveliev
- Program for Molecular Neurobiology, Institute of Biotechnology, Viikki Biocenter, University of Helsinki, Helsinki FIN-00014, Finland
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31
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Mikaels-Edman A, Baudet C, Ernfors P. Soluble and bound forms of GFRalpha1 elicit different GDNF-independent neurite growth responses in primary sensory neurons. Dev Dyn 2003; 227:27-34. [PMID: 12701096 DOI: 10.1002/dvdy.10280] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We have investigated the role of glial cell-line derived neurotrophic factor (GDNF) and the effect of soluble or immobilized localization of its GDNF family receptor alpha1 (GFRalpha1) on neurite growth in cultured embryonic Bax(-/-) dorsal root ganglion neurons, which survive in the absence of trophic support. Whereas GDNF alone has a moderate effect on neurite growth, soluble and immobilized GFRalpha1 elicit opposing and GDNF-independent effects on neurite growth by a phospholipase C (PLC) gamma-dependent mechanism. Thus, GFRalpha1 elicits nerve growth responses independent of GDNF. However, GDNF in the presence of soluble or immobilized GFRalpha1 reverse the GDNF-independent GFRalpha1 modulation of neurite growth. The different outcome of soluble and bound GFRalpha1 combined with our previous immunohistochemical data showing GFRalpha1-protein in Schwann cells but not axons suggest terminal Schwann cells as a source of locally administered target-derived GFRalpha1 and place this receptor in the path of axonal growth and guidance. Thus, target-derived GFRalpha1 play opposing roles when presented alone and with GDNF and, therefore, can function as a nerve growth cue that both can promote and prevent growth in the developing peripheral nervous system.
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Affiliation(s)
- Asa Mikaels-Edman
- Laboratory of Molecular Neurobiology, MBB, Karolinska Institute, Stockholm, Sweden
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32
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Kawakami T, Wakabayashi Y, Aimi Y, Isono T, Okada Y. Developmental expression of glial cell-line derived neurotrophic factor, neurturin, and their receptor mRNA in the rat urinary bladder. Neurourol Urodyn 2003; 22:83-8. [PMID: 12478607 DOI: 10.1002/nau.10074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AIMS Glial cell-line derived neurotrophic factor (GDNF) and related factors neurturin (NRTN), artemin, and persephin are members of the GDNF family of neurotrophic factors. GDNF and NRTN bind to the tyrosine kinase receptor Ret and the receptors GFRalpha1 and GFRalpha2. The objective was to examine the developmental expression of GDNF, NRTN, and their receptors within the rat urinary bladder. METHODS Rat bladders dissected from embryonic day (E) 15, postnatal day (P) 0, P14, P28, and adult rats (P60) were investigated by semiquantitative reverse transcriptase polymerase chain reaction. Embryos (E15, E16, and E17) were immunohistochemically stained for neurofilament. RESULTS GDNF and Ret mRNA levels at E15 were the highest of all the stages we examined and then immediately decreased. In contrast, NRTN mRNA levels did not change between E15 and postnatal day 14; thereafter, they gradually but insignificantly increased. GFRalpha1 and GFRalpha2 mRNA levels were high at E15, after which their signal intensities decreased. In whole-mounted specimens, neurofilament-positive axons were first detected in the bladder at E16. CONCLUSIONS Our results suggest that GDNF and NRTN may act as trophic factors for neural in-growth to the bladder and/or for the maintenance of mature neurons innervating the bladder. These factors might also be involved in bladder morphogenesis.
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Affiliation(s)
- Takahiro Kawakami
- Department of Urology, Shiga University of Medical Science, Otsu, Japan
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33
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Cullen-McEwen LA, Kett MM, Dowling J, Anderson WP, Bertram JF. Nephron number, renal function, and arterial pressure in aged GDNF heterozygous mice. Hypertension 2003; 41:335-40. [PMID: 12574104 DOI: 10.1161/01.hyp.0000050961.70182.56] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The loss of one allele for glial cell line-derived neurotrophic factor (GDNF) results in approximately 30% fewer but normal sized glomeruli in young mice. Low nephron number, inherited or acquired, has been linked to increased risk of development of hypertension and renal failure. This study examines whether GDNF heterozygous mice, with an inherent reduction in nephron number, demonstrate a deterioration in renal structure and function and rise in arterial pressure in later life. Fourteen-month-old male GDNF heterozygous (n=7) and wild-type (n=6) mice were anesthetized and prepared for measurement of mean arterial pressure, glomerular filtration rate (GFR), and renal blood flow. After measurement of renal function, kidneys were fixed for stereological determination of total glomerular number and mean glomerular volume. Mean arterial pressure was, on average, 18 mm Hg higher in GDNF heterozygous (98+/-4 mm Hg) than wild-type mice (80+/-2 mm Hg; P<0.01). However, GFR (0.656+/-0.054 versus 0.688+/-0.076 mL/min per g kidney wt) and renal blood flow (5.29+/-0.42 versus 4.70+/-0.34 mL/min per g kidney wt) were not different between groups. Fourteen-month-old GDNF heterozygous mice had approximately 30% fewer glomeruli than wild-type mice (9206+/-934 versus 13440+/-1275; P<0.01) and significantly larger glomeruli (4.51+/-0.39 versus 3.72+/-0.63x10(-4)mm(3); P<0.01). Thus, aged GDNF heterozygous mice maintained a normal GFR and renal blood flow despite reduced nephron numbers. The elevated arterial pressure, glomerular hypertrophy, and hyperfiltration demonstrated in the GDNF heterozygous mice at this age may indicate a compensatory mechanism whereby GFR is maintained in the presence of a reduced nephron endowment.
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Fundin BT, Rice FL, Ernfors P. Patterned gene programs and target remodeling following axotomy at a major site for sensory innervation. JOURNAL OF NEUROBIOLOGY 2002; 53:370-80. [PMID: 12382264 DOI: 10.1002/neu.10118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The genetic mechanisms that a target uses to reestablish the connections of regenerating axons were explored using oligonucleotide microarrays and real-time PCR. In normal and denervated mouse vibrissa follicles, patterns of genetic regulation were assessed in adjacent targets that normally receive different types of sensory and autonomic innervation. We show that a target remodeling occurs following axotomy involving reduced hair growth, altered hair follicle integrity and remodeling of the extracellular matrix. Also, we found two orphan receptors putatively involved in hair growth. Our data further demonstrate region-specific regulation of genes putatively involved in target-axon interactions. Thus, this study shows for the first time that major target remodeling occurs following denervation and suggests putative functions for several novel genes.
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Affiliation(s)
- Bengt T Fundin
- Unit of Molecular Neurobiology, MBB, Karolinska Institute, Scheelesvag 1, 17177 Stockholm, Sweden
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35
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Ledda F, Paratcha G, Ibáñez CF. Target-derived GFRalpha1 as an attractive guidance signal for developing sensory and sympathetic axons via activation of Cdk5. Neuron 2002; 36:387-401. [PMID: 12408843 DOI: 10.1016/s0896-6273(02)01002-4] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Immobilized and diffusible molecular cues regulate axon guidance during development. GFRalpha1, a GPI-anchored receptor for GDNF, is expressed as both membrane bound and secreted forms by accessory nerve cells and peripheral targets of developing sensory and sympathetic neurons during the period of target innervation. A relative deficit of GFRalpha1 in developing axons allows exogenous GFRalpha1 to capture GDNF and present it for recognition by axonal c-Ret receptors. Exogenous GFRalpha1 potentiates neurite outgrowth and acts as a long-range directional cue by creating positional information for c-Ret-expressing axons in the presence of a uniform concentration of GDNF. Soluble GFRalpha1 prolongs GDNF-mediated activation of cyclin-dependent kinase 5 (Cdk5), an event required for GFRalpha1-induced neurite outgrowth and axon guidance. Together with GDNF, target-derived GFRalpha1 can function in a non-cell-autonomous fashion as a chemoattractant cue with outgrowth promoting activity for peripheral neurons.
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Affiliation(s)
- Fernanda Ledda
- Division of Molecular Neurobiology, Department of Neuroscience, Karolinska Institute, 17177 Stockholm, Sweden
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36
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Airaksinen MS, Saarma M. The GDNF family: signalling, biological functions and therapeutic value. Nat Rev Neurosci 2002; 3:383-94. [PMID: 11988777 DOI: 10.1038/nrn812] [Citation(s) in RCA: 1324] [Impact Index Per Article: 60.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Members of the nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) families comprising neurotrophins and GDNF-family ligands (GFLs), respectively are crucial for the development and maintenance of distinct sets of central and peripheral neurons. Knockout studies in the mouse have revealed that members of these two families might collaborate or act sequentially in a given neuron. Although neurotrophins and GFLs activate common intracellular signalling pathways through their receptor tyrosine kinases, several clear differences exist between these families of trophic factors.
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Affiliation(s)
- Matti S Airaksinen
- Programme of Molecular Neurobiology, Institute of Biotechnology, P.O. Box 56, Viikki Biocenter, FIN-00014, University of Helsinki, Finland.
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37
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Abstract
Sensorimotor disturbances are common among elderly and one of the main factors depreciating life quality in senescence. Mechanistically sensory deficits during aging include not only degenerative and regressive events but also phenotypic switches among sensory neurons as well as remodeling of sensory innervation. The pattern of changes suggests that an underlying mechanism is a sustained dependence of sensory neurons on target tissues, and that this dependence, at least in part, appears to be mediated through signaling by target-derived trophic factors. This review presents and discusses evidence supporting this notion.
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Affiliation(s)
- B Ulfhak
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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38
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Linnarsson S, Mikaels A, Baudet C, Ernfors P. Activation by GDNF of a transcriptional program repressing neurite growth in dorsal root ganglia. Proc Natl Acad Sci U S A 2001; 98:14681-6. [PMID: 11724954 PMCID: PMC64741 DOI: 10.1073/pnas.251548898] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2000] [Accepted: 10/15/2001] [Indexed: 12/30/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) promotes the survival of postnatal-but not embryonic-mouse dorsal root ganglion cells in vitro, despite the fact that its receptors are expressed at both ages. To understand this difference, we have performed an oligonucleotide microarray experiment. We found that several hundred genes were regulated between embryonic and postnatal stages, and that several important classes of genes were differentially regulated by GDNF treatment, including genes related to translation and to phenotypic specification and maturation. Interestingly, a set of genes related to cell adhesion, cytoskeleton and cellular morphology were consistently down-regulated by GDNF, suggesting a previously uncharacterized role for GDNF in repressing neurite growth and/or branching. This nuclear program initiated by GDNF was functionally confirmed in cultures of embryonic wild-type neurons sustained with nerve growth factor and in bax(-/-) neurons that survive in the absence of trophic support.
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Affiliation(s)
- S Linnarsson
- Department of Medical Biophysics and Biochemistry, Molecular Neurobiology Unit, Scheeles väg 1, Karolinska Institutet, S-171 77 Stockholm, Sweden
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39
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Johnson WE, Evans H, Menage J, Eisenstein SM, El Haj A, Roberts S. Immunohistochemical detection of Schwann cells in innervated and vascularized human intervertebral discs. Spine (Phila Pa 1976) 2001; 26:2550-7. [PMID: 11725235 DOI: 10.1097/00007632-200112010-00007] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN The ingrowth of nerves, blood vessels, and Schwann cells into human intervertebral discs was examined using immunohistochemistry for cell-type-specific markers. OBJECTIVES To determine whether Schwann cells may contribute to disc innervation, and to assess the relation between disc innervation and vascularization. SUMMARY OF BACKGROUND DATA Intervertebral disc degeneration was associated previously with ingrowth of blood vessels and nerves. Schwann cells are known to play an important role in regulating nerve growth and survival in other tissues, but they have not been examined in human pathologic intervertebral discs. METHODS Serial sections of human intervertebral discs were immunostained for the neuronal markers (neurofilament 200, peripherin, protein gene product 9.5), for the Schwann cell marker (glial fibrillary acidic protein), and for the endothelial cell marker (CD34). RESULTS Glial fibrillary acidic protein-immunopositive cells colocalized with nerves in degenerate discs, but were absent or rarely observed in nondegenerate, aneural discs. These also were seen in the disc matrix, independently of nerves. Much of the nerve and Schwann cell ingrowth was found in vascularized areas of disc tissue, where the lamellar structure of the anulus fibrosus was disrupted. Blood vessels were observed deeper into the discs than nerves or Schwann cells. CONCLUSIONS The appearance of glial fibrillary acidic protein-immunopositive cells in diseased intervertebral discs was closely associated with nerve ingrowth. This novel finding suggests that Schwann cells have a role to play in regulating disc innervation and nerve function in the disc. Because blood vessels were observed furthermost into the disc, it is possible that degenerate disc vascularization occurs before innervation.
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Affiliation(s)
- W E Johnson
- J.P. O'Brien Laboratory, Centre for Spinal Studies, Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, Shropshire SY10 7AG, United Kingdom.
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40
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Sukumaran M, Waxman SG, Wood JN, Pachnis V. Flanking regulatory sequences of the locus encoding the murine GDNF receptor, c-ret, directs lac Z (beta-galactosidase) expression in developing somatosensory system. Dev Dyn 2001; 222:389-402. [PMID: 11747074 DOI: 10.1002/dvdy.1192] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
RET forms the catalytic component within the receptor complex that transmits signals from the GDNF family of neurotrophic factors. To study the mechanisms regulating the cell-type specific expression of this gene, we have cloned and characterised the murine c-ret locus. A cosmid contig comprising approximately 60 kb of the mouse genome encompassing the entire structural gene and flanking sequences have been isolated and the transcription initiation site identified and promoter characterised. The murine c-ret promoter lacks a TATA initiation motif and has GC enriched DNA sequences reminiscent of CpG islands. Analysis of transgenic mice lines bearing the Lac Z (beta-galactosidase) reporter gene under the control of 5' flanking sequences show modularity in the organisation of cis-regulatory domains within the locus. Cloned 5' flanking sequences comprise a distal regulatory domain directing Lac Z expression at the primitive streak, lateral mesoderm and facial ganglia and a proximal sensory neurones specific regulatory domain inducing Lac Z expression primarily within the developing somatosensory system. The spatial and temporal progression of transgene expression precisely recapitulates endogenous gene expression in developing sensory ganglia including its induction in postnatal Isolectin B4 binding nociceptive neurones.
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MESH Headings
- Animals
- Animals, Newborn/metabolism
- Base Sequence/genetics
- Chromosome Mapping
- Cloning, Molecular
- Consensus Sequence/genetics
- Drosophila Proteins
- Embryo, Mammalian/physiology
- Ganglia, Sensory/embryology
- Gene Expression
- Gene Expression Regulation, Developmental/physiology
- Genes, Regulator/genetics
- Glial Cell Line-Derived Neurotrophic Factor Receptors
- Lac Operon/genetics
- Lectins/metabolism
- Mice/embryology
- Mice/genetics
- Mice, Transgenic/genetics
- Neurons, Afferent/metabolism
- Nociceptors/metabolism
- Promoter Regions, Genetic/genetics
- Protein Structure, Tertiary/physiology
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins c-ret
- Receptor Protein-Tyrosine Kinases/genetics
- Spinal Cord/embryology
- Transcription Initiation Site/physiology
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Affiliation(s)
- M Sukumaran
- Division of Developmental Neurobiology, National Institute for Medical Research, London, United Kingdom.
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41
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Harris SJ, Jahoda CA. A correlation between versican and neurofilament expression patterns during the development and adult cycling of rat vibrissa follicles. Mech Dev 2001; 101:227-31. [PMID: 11231081 DOI: 10.1016/s0925-4773(00)00561-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Versican, a proteoglycan recently implicated in hair follicle induction, has been shown to influence axon outgrowth in vitro and in vivo. We used immunohistochemistry to study the relationship between versican expression and innervation, during rat vibrissa follicle development and the adult hair cycle. During development, nerve fibres were commonly associated with areas of weak versican expression, and the path of axons appeared to be delineated by sharp boundaries of versican expression. Versican expression changed in the lower follicle dermis during the adult hair follicle cycle but remained strong around the follicle neck reflecting the constant innervation. Our observations show a correlation between versican expression and peripheral innervation indicating that versican may have a dual role in hair follicle biology.
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Affiliation(s)
- S J Harris
- Biological Sciences Department, University of Durham, South Road, DH1 3LE, Durham, UK.
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42
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Abstract
BACKGROUND/PURPOSE Aberrant neural crest migration is implicated in the pathogenesis of hindgut aganglionosis in Hirschsprung's disease (HSCR). Neural crest progenitors also give rise to a variety of cell types outside the gut, including nerves of the inner ear and peripheral nervous system. This study aims to determine whether such nerves are also affected in HSCR. METHODS Pure tone audiometry and oto-acoustic emission tests were performed on 53 patients with Hirschsprung's disease and 28 age-matched controls. Forty-two children with Hirschsprung's disease and 30 age-matched controls also underwent neurologic evaluation, including quantitative peripheral tests of sensory function. RESULTS Moderate to severe sensorineural hearing loss (1 profound [Waardenburg syndrome] and 3 high frequency) was detected in 4 children (8%) from the Hirschsprung's group. Abnormal (absent or reduced) oto-acoustic emission was detected in 77 of 102 ears (41 of 51 patients) in the HSCR group and 8 out of 48 ears (6 of 24 children) in the control group (75% v 17%; P<.0001). Two HSCR children had marked abnormalities on tests of peripheral nerve function. Significantly higher thresholds for vibration sensation were detected in HSCR versus controls (P<.05). CONCLUSION Hirschsprung's disease may have a more generalised neuropathy than just that involving the affected bowel.
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Affiliation(s)
- W Cheng
- Division of Paediatric Surgery, Division of ENT, Department of Surgery, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong, SAR, China
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43
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Abstract
Neurotrophins regulate development, maintenance, and function of vertebrate nervous systems. Neurotrophins activate two different classes of receptors, the Trk family of receptor tyrosine kinases and p75NTR, a member of the TNF receptor superfamily. Through these, neurotrophins activate many signaling pathways, including those mediated by ras and members of the cdc-42/ras/rho G protein families, and the MAP kinase, PI-3 kinase, and Jun kinase cascades. During development, limiting amounts of neurotrophins function as survival factors to ensure a match between the number of surviving neurons and the requirement for appropriate target innervation. They also regulate cell fate decisions, axon growth, dendrite pruning, the patterning of innervation and the expression of proteins crucial for normal neuronal function, such as neurotransmitters and ion channels. These proteins also regulate many aspects of neural function. In the mature nervous system, they control synaptic function and synaptic plasticity, while continuing to modulate neuronal survival.
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Affiliation(s)
- Eric J Huang
- Department of Pathology, University of California, San Francisco, California 94143; e-mail:
| | - Louis F Reichardt
- Department of Physiology, University of California, San Francisco, California 94143, and Howard Hughes Medical Institute, San Francisco, California 94143; e-mail:
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Paratcha G, Ledda F, Baars L, Coulpier M, Besset V, Anders J, Scott R, Ibáñez CF. Released GFRalpha1 potentiates downstream signaling, neuronal survival, and differentiation via a novel mechanism of recruitment of c-Ret to lipid rafts. Neuron 2001; 29:171-84. [PMID: 11182089 DOI: 10.1016/s0896-6273(01)00188-x] [Citation(s) in RCA: 224] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Although both c-Ret and GFRalpha1 are required for responsiveness to GDNF, GFRalpha1 is widely expressed in the absence of c-Ret, suggesting alternative roles for "ectopic" sites of GFRalpha1 expression. We show that GFRalpha1 is released by neuronal cells, Schwann cells, and injured sciatic nerve. c-Ret stimulation in trans by soluble or immobilized GFRalpha1 potentiates downstream signaling, neurite outgrowth, and neuronal survival, and elicits dramatic localized expansions of axons and growth cones. Soluble GFRalpha1 mediates robust recruitment of c-Ret to lipid rafts via a novel mechanism requiring the c-Ret tyrosine kinase. Activated c-Ret associates with different adaptor proteins inside and outside lipid rafts. These results provide an explanation for the tissue distribution of GFRalpha1, supporting the physiological importance of c-Ret activation in trans as a novel mechanism to potentiate and diversify the biological responses to GDNF.
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Affiliation(s)
- G Paratcha
- Division of Molecular Neurobiology, Department of Neuroscience, Karolinska Institute, 17177, Stockholm, Sweden
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45
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Baudet C, Mikaels A, Westphal H, Johansen J, Johansen TE, Ernfors P. Positive and negative interactions of GDNF, NTN and ART in developing sensory neuron subpopulations, and their collaboration with neurotrophins. Development 2000; 127:4335-44. [PMID: 11003834 DOI: 10.1242/dev.127.20.4335] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF), neurturin (NTN) and neublastin/artemin (ART) are distant members of the transforming growth factor beta family, and have been shown to elicit neurotrophic effects upon several classes of peripheral and central neurons. Limited information from in vitro and expression studies has also substantiated a role for GDNF family ligands in mammalian somatosensory neuron development. Here, we show that although dorsal root ganglion (DRG) sensory neurons express GDNF family receptors embryonically, they do not survive in response to their ligands. The regulation of survival emerges postnatally for all GDNF family ligands. GDNF and NTN support distinct subpopulations that can be separated with respect to their expression of GDNF family receptors, whereas ART supports neurons in populations that are also responsive to GDNF or NTN. Sensory neurons that coexpress GDNF family receptors are medium sized, whereas small-caliber nociceptive cells preferentially express a single receptor. In contrast to brain-derived neurotrophic factor (BDNF)-dependent neurons, embryonic nerve growth factor (NGF)-dependent nociceptive neurons switch dependency to GDNF, NTN and ART postnatally. Neurons that survive in the presence of neurotrophin 3 (NT3) or neurotrophin 4 (NT4), including proprioceptive afferents, Merkel end organs and D-hair afferents, are also supported by GDNF family ligands neonatally, although at postnatal stages they lose their dependency on GDNF and NTN. At late postnatal stages, ART prevents survival elicited by GDNF and NTN. These data provide new insights on the roles of GDNF family ligands in sensory neuron development.
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Affiliation(s)
- C Baudet
- Laboratory of Molecular Neurobiology, Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 77 Stockholm, Sweden
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46
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Bergman E, Ulfhake B, Fundin BT. Regulation of NGF-family ligands and receptors in adulthood and senescence: correlation to degenerative and regenerative changes in cutaneous innervation. Eur J Neurosci 2000; 12:2694-706. [PMID: 10971613 DOI: 10.1046/j.1460-9568.2000.00149.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
During development, a highly differential neurotrophin dependency is reported for various types of nerve endings in the whisker follicle. To what extent these dependencies extend and play a role in adulthood is largely unresolved. We show here, using in situ hybridization and immunohistochemistry that the expression of neurotrophins and trk/p75 receptors persists in adulthood. As suggested by their expression profiles, many classes of cutaneous nerve endings disclose similar ligand-receptor dependencies in adult animals as during development, while other populations appear to switch their dependency. Furthermore, our data suggest that sensory endings that have a high turnover due to mechanical wear and tear, e. g. Merkel cell-neurite complexes at the level of ring sinus show a more complex ligand-receptor expression phenotype than do endings with a less vulnerable location, e.g. the Merkel cell-neurite complexes at the rete ridge collar. Thus, neurotrophin-3 (NT3)/trkA signalling is suggested to be important for a continuous terminal plasticity of Merkel cell-neurite complexes at the level of ring sinus in adulthood. Evidence supporting a role for neurotrophin signalling in maintaining the adult cutaneous innervation also comes from the close correlation between altered ligand-receptor expression(s) and axonal/terminal aberrations in senescence. Thus, an ageing-related decrease in target neurotrophin expression, notably NT3 and NT4, results in a site-specific loss of sensory terminals concomitant with an aberrant growth of regenerating/sprouting axons into new target fields. Ageing of the cutaneous innervation, manifested in degenerative and regenerative events, seems strongly associated with changes in neurotrophic interactions between sensory neurons and target tissues.
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MESH Headings
- Aging/physiology
- Animals
- Brain-Derived Neurotrophic Factor/genetics
- Brain-Derived Neurotrophic Factor/metabolism
- Cavernous Sinus/innervation
- Female
- Fluorescent Antibody Technique
- Gene Expression Regulation, Developmental
- Hair Follicle/innervation
- In Situ Hybridization
- Ligands
- Maxillary Nerve/chemistry
- Maxillary Nerve/metabolism
- Merkel Cells/chemistry
- Merkel Cells/metabolism
- Nerve Degeneration/metabolism
- Nerve Growth Factors/genetics
- Nerve Growth Factors/metabolism
- Nerve Regeneration/physiology
- Neurotrophin 3/genetics
- Neurotrophin 3/metabolism
- RNA, Messenger/analysis
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor/analysis
- Receptor, Nerve Growth Factor/genetics
- Receptor, Nerve Growth Factor/metabolism
- Receptor, trkA/analysis
- Receptor, trkA/genetics
- Receptor, trkA/metabolism
- Receptor, trkB/analysis
- Receptor, trkB/genetics
- Receptor, trkB/metabolism
- Receptor, trkC/analysis
- Receptor, trkC/genetics
- Receptor, trkC/metabolism
- Receptors, Nerve Growth Factor/analysis
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/metabolism
- Vibrissae/innervation
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Affiliation(s)
- E Bergman
- Department of Neuroscience, Karolinska Institutet, S171 77 Stockholm, Sweden
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47
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Botchkareva NV, Botchkarev VA, Welker P, Airaksinen M, Roth W, Suvanto P, Müller-Röver S, Hadshiew IM, Peters C, Paus R. New roles for glial cell line-derived neurotrophic factor and neurturin: involvement in hair cycle control. THE AMERICAN JOURNAL OF PATHOLOGY 2000; 156:1041-53. [PMID: 10702420 PMCID: PMC1876831 DOI: 10.1016/s0002-9440(10)64972-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF), neurturin (NTN), and their receptors, GDNF family receptor alpha-1 (GFRalpha-1) and GDNF family receptor alpha-2 (GFRalpha-2), are critically important for kidney and nervous system development. However, their role in skin biology, specifically in hair growth control, is as yet unknown. We have studied expression and function of GDNF, neurturin, GFRalpha-1, and GFRalpha-2 in murine skin during the cyclic transformation of the hair follicle (HF) from its resting state (telogen) to active growth (anagen) and then through regression (catagen) back to telogen. GDNF protein and GFRalpha-1 messenger RNA are prominently expressed in telogen skin, which lacks NTN and GFRalpha-2 transcripts. Early anagen development is accompanied by a significant decline in the skin content of GDNF protein and GFRalpha-1 transcripts. During the anagen-catagen transition, GDNF, GFRalpha-1, NTN, and GFRalpha-2 transcripts reach maximal levels. Compared with wild-type controls, GFRalpha-1 (+/-) and GFRalpha-2 (-/-) knockout mice show a significantly accelerated catagen development. Furthermore, GDNF or NTN administration significantly retards HF regression in organ-cultured mouse skin. This suggests important, previously unrecognized roles for GDNF/GFRalpha-1 and NTN/GFRalpha-2 signaling in skin biology, specifically in the control of apoptosis-driven HF involution, and raises the possibility that GFRalpha-1/GFRalpha-2 agonists/antagonists might become exploitable for the treatment of hair growth disorders that are related to abnormalities in catagen development.
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Affiliation(s)
- N V Botchkareva
- Department of Dermatology, Charité, Humboldt University, Berlin, Germany
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48
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Patel TD, Jackman A, Rice FL, Kucera J, Snider WD. Development of sensory neurons in the absence of NGF/TrkA signaling in vivo. Neuron 2000; 25:345-57. [PMID: 10719890 DOI: 10.1016/s0896-6273(00)80899-5] [Citation(s) in RCA: 299] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The neurotrophin survival dependence of peripheral neurons in vitro is regulated by the proapoptotic BCL-2 homolog BAX. To study peripheral neuron development in the absence of neurotrophin signaling, we have generated mice that are double null for BAX and nerve growth factor (NGF), and BAX and the NGF receptor TrkA. All dorsal root ganglion (DRG) neurons that normally die in the absence of NGF/TrkA signaling survive if BAX is also eliminated. These neurons extend axons through the dorsal roots and collateral branches into the dorsal horn. In contrast, superficial cutaneous innervation is absent. Furthermore, rescued sensory neurons fail to express biochemical markers characteristic of the nociceptive phenotype. These findings establish that NGF/TrkA signaling regulates peripheral target field innervation and is required for the full phenotypic differentiation of sensory neurons.
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MESH Headings
- Animals
- Calcitonin Gene-Related Peptide/genetics
- Cell Count
- Cell Differentiation/drug effects
- Cell Survival/drug effects
- Cells, Cultured
- Female
- Ganglia, Spinal/cytology
- Ganglia, Spinal/embryology
- Gene Expression Regulation, Developmental
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Nerve Growth Factor/pharmacology
- Neurons, Afferent/chemistry
- Neurons, Afferent/cytology
- Neurons, Afferent/physiology
- Phenotype
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins c-bcl-2
- Receptor, trkA/genetics
- Signal Transduction/physiology
- Skin/innervation
- Spinal Cord/cytology
- Substance P/genetics
- bcl-2-Associated X Protein
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Affiliation(s)
- T D Patel
- University of North Carolina Neuroscience Center, University of North Carolina, Chapel Hill 27599, USA
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49
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Baloh RH, Enomoto H, Johnson EM, Milbrandt J. The GDNF family ligands and receptors - implications for neural development. Curr Opin Neurobiol 2000; 10:103-10. [PMID: 10679429 DOI: 10.1016/s0959-4388(99)00048-3] [Citation(s) in RCA: 357] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The glial cell line derived neurotrophic factor (GDNF) family has recently been expanded to include four members, and the interactions between these neurotrophic factors and their unique receptor system is now beginning to be understood. Furthermore, analysis of mice lacking the genes for GDNF, neurturin, and their related receptors has confirmed the importance of these factors in neurodevelopment. The results of such analyses reveal numerous similarities and potential overlaps in the way the GDNF and the nerve growth factor (NGF) families regulate development of the peripheral nervous system.
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Affiliation(s)
- R H Baloh
- Departments of Pathology and Internal Medicine, Washington University School of Medicine, St Louis, MO 63110, USA.
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50
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Mikaels A, Livet J, Westphal H, De Lapeyrière O, Ernfors P. A dynamic regulation of GDNF-family receptors correlates with a specific trophic dependency of cranial motor neuron subpopulations during development. Eur J Neurosci 2000; 12:446-56. [PMID: 10712625 DOI: 10.1046/j.1460-9568.2000.00924.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) family ligands promote the survival of developing motor neurons in vivo and in vitro. However, not all neurons survive with any single ligand in culture and GDNF null mutant mice display only a partial motor neuron loss. An interesting possibility is that subpopulations of motor neurons based on their function and/or their myotopic organization require distinct members of GDNF family ligands. Because responsiveness to the different ligands depends on the expression of their cognate ligand-binding receptor we have herein addressed this issue by examining the expression of GDNF-family receptors (gfr) during development and in the adult in cranial motor nuclei subpopulations. We have furthermore examined the in vivo role of GDNF for cranial motor neuron subpopulations. The shared ret receptor was expressed in all somatic, branchial and visceral cranial embryonic motor nuclei examined, showing that they are all competent to respond to GDNF family ligands during development. At early stages of development both the GDNF receptor, gfralpha1, and the neurturin (NTN) receptor, gfralpha2, were expressed in the oculomotor, facial and spinal accessory, and only gfralpha1 in the trochlear, superior salivatory, trigeminal, hypoglossal and weakly in the dorsal motor nucleus of the vagus and the ambiguous nucleus. The abducens nucleus was negative for both gfralpha1 and gfralpha2. The artemin (ART) receptor, gfralpha3, was expressed only in the superior salivatory nucleus. A motor neuron subnuclei-specific expression of gfralpha1 and gfralpha2 was seen in the facial and trigeminal nuclei which corresponded to their dependence on GDNF in null mutant mice. We found that the expression was dynamic in these nuclei, which may reflect developmental changes in their trophic factor dependency. Analysis of GDNF null mutant mice revealed that the dynamic receptor expression is regulated by the ligand in vivo, indicating that the attainment of changes in dependency could be ligand induced. Our results indicate that specific GDNF family ligands support selective muscle-motor neuron circuits during development.
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Affiliation(s)
- A Mikaels
- Laboratory of Molecular Neurobiology, MBB, Karolinska Institute, S171 77 Stockholm, Sweden
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