1
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Tasnim A, Alkislar I, Hakim R, Turecek J, Abdelaziz A, Orefice LL, Ginty DD. The developmental timing of spinal touch processing alterations predicts behavioral changes in genetic mouse models of autism spectrum disorders. Nat Neurosci 2024; 27:484-496. [PMID: 38233682 PMCID: PMC10917678 DOI: 10.1038/s41593-023-01552-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 12/12/2023] [Indexed: 01/19/2024]
Abstract
Altered somatosensory reactivity is frequently observed among individuals with autism spectrum disorders (ASDs). Here, we report that although multiple mouse models of ASD exhibit aberrant somatosensory behaviors in adulthood, some models exhibit altered tactile reactivity as early as embryonic development, whereas in others, altered reactivity emerges later in life. Additionally, tactile overreactivity during neonatal development is associated with anxiety-like behaviors and social behavior deficits in adulthood, whereas tactile overreactivity that emerges later in life is not. The locus of circuit disruption dictates the timing of aberrant tactile behaviors, as altered feedback or presynaptic inhibition of peripheral mechanosensory neurons leads to abnormal tactile reactivity during neonatal development, whereas disruptions in feedforward inhibition in the spinal cord lead to touch reactivity alterations that manifest later in life. Thus, the developmental timing of aberrant touch processing can predict the manifestation of ASD-associated behaviors in mouse models, and differential timing of sensory disturbance onset may contribute to phenotypic diversity across individuals with ASD.
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Affiliation(s)
- Aniqa Tasnim
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Ilayda Alkislar
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Richard Hakim
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Josef Turecek
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Amira Abdelaziz
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA
| | - Lauren L Orefice
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - David D Ginty
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA.
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2
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El-Agamy SE, Guillaud L, Kono K, Wu Y, Terenzio M. FMRP Long-Range Transport and Degradation Are Mediated by Dynlrb1 in Sensory Neurons. Mol Cell Proteomics 2023; 22:100653. [PMID: 37739344 PMCID: PMC10625159 DOI: 10.1016/j.mcpro.2023.100653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 09/10/2023] [Accepted: 09/18/2023] [Indexed: 09/24/2023] Open
Abstract
The fragile X messenger ribonucleoprotein 1 (FMRP) is a multifunctional RNA-binding protein implicated in human neurodevelopmental and neurodegenerative disorders. FMRP mediates the localization and activity-dependent translation of its associated mRNAs through the formation of phase-separated condensates that are trafficked by microtubule-based motors in axons. Axonal transport and localized mRNA translation are critical processes for long-term neuronal survival and are closely linked to the pathogenesis of neurological diseases. FMRP dynein-mediated axonal trafficking is still largely unexplored but likely to constitute a key process underlying FMRP spatiotemporal translational regulation. Here, we show that dynein light chain roadblock 1 (Dynlrb1), a subunit of the dynein complex, is a critical regulator of FMRP function. In sensory axons, FMRP associates with endolysosomal organelles, likely through annexin A11, and is retrogradely trafficked by the dynein complex in a Dynlrb1-dependent manner. Moreover, Dynlrb1 silencing induced FMRP granule accumulation and repressed the translation of microtubule-associated protein 1b, one of its primary mRNA targets. Our findings suggest that Dynlrb1 regulates FMRP function through the control of its transport and targeted degradation.
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Affiliation(s)
- Sara Emad El-Agamy
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Okinawa, Japan
| | - Laurent Guillaud
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Okinawa, Japan
| | - Keiko Kono
- Membranology Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Okinawa, Japan
| | - Yibo Wu
- YCI Laboratory for Next-Generation Proteomics, RIKEN Center of Integrative Medical Sciences, Yokohama, Kanagawa, Japan; Chemical Biology Mass Spectrometry Platform (ChemBioMS), Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Marco Terenzio
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Okinawa, Japan.
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3
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Fernandez A, Sarn N, Eng C, Wright KM. Intrinsic control of DRG sensory neuron diversification by Pten. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.552039. [PMID: 37781577 PMCID: PMC10541114 DOI: 10.1101/2023.08.04.552039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Phosphatase and tensin homolog (PTEN) modulates intracellular survival and differentiation signaling pathways downstream of neurotrophin receptors in the developing peripheral nervous system (PNS). Although well-studied in the context of brain development, our understanding of the in vivo role of PTEN in the PNS is limited to models of neuropathic pain and nerve injury. Here, we assessed how alterations in PTEN signaling affects the development of peripheral somatosensory circuits. We found that sensory neurons within the dorsal root ganglia (DRG) in Pten heterozygous ( Pten Het ) mice exhibit defects in neuronal subtype diversification. Abnormal DRG differentiation in Pten Het mice arises early in development, with subsets of neurons expressing both progenitor and neuronal markers. DRGs in Pten Het mice show dysregulation of both mTOR and GSK-3β signaling pathways downstream of PTEN. Finally, we show that mice with an autism-associated mutation in Pten ( Pten Y68H/+ ) show abnormal DRG development. Thus, we have discovered a crucial role for PTEN signaling in the intrinsic diversification of primary sensory neuron populations in the DRG during development.
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4
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Tasnim A, Alkislar I, Hakim R, Turecek J, Abdelaziz A, Orefice LL, Ginty DD. The developmental timing of spinal touch processing alterations and its relation to ASD-associated behaviors in mouse models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.09.539589. [PMID: 37214862 PMCID: PMC10197556 DOI: 10.1101/2023.05.09.539589] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Altered somatosensory reactivity is frequently observed among individuals with autism spectrum disorders (ASDs). Here, we report that while multiple mouse models of ASD exhibit aberrant somatosensory behaviors in adulthood, some models exhibit altered tactile reactivity as early as embryonic development, while in others, altered reactivity emerges later in life. Additionally, tactile over-reactivity during neonatal development is associated with anxiety-like behaviors and social interaction deficits in adulthood, whereas tactile over-reactivity that emerges later in life is not. The locus of circuit disruption dictates the timing of aberrant tactile behaviors: altered feedback or presynaptic inhibition of peripheral mechanosensory neurons leads to abnormal tactile reactivity during neonatal development, while disruptions in feedforward inhibition in the spinal cord lead to touch reactivity alterations that manifest later in life. Thus, the developmental timing of aberrant touch processing can predict the manifestation of ASD-associated behaviors in mouse models, and differential timing of sensory disturbance onset may contribute to phenotypic diversity across individuals with ASD.
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5
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Mitchell ME, Cook LC, Shiers S, Tavares-Ferreira D, Akopian AN, Dussor G, Price TJ. Characterization of Fragile X Mental Retardation Protein expression in human nociceptors and their axonal projections to the spinal dorsal horn. J Comp Neurol 2023; 531:814-835. [PMID: 36808110 PMCID: PMC10038933 DOI: 10.1002/cne.25463] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/20/2022] [Accepted: 01/27/2023] [Indexed: 02/23/2023]
Abstract
Fragile X Mental Retardation Protein (FMRP) regulates activity-dependent RNA localization and local translation to modulate synaptic plasticity throughout the central nervous system. Mutations in the FMR1 gene that hinder or ablate FMRP function cause Fragile X Syndrome (FXS), a disorder associated with sensory processing dysfunction. FXS premutations are associated with increased FMRP expression and neurological impairments including sex dimorphic presentations of chronic pain. In mice, FMRP ablation causes dysregulated dorsal root ganglion (DRG) neuron excitability and synaptic vesicle exocytosis, spinal circuit activity, and decreased translation-dependent nociceptive sensitization. Activity-dependent, local translation is a key mechanism for enhancing primary nociceptor excitability that promotes pain in animals and humans. These works indicate that FMRP likely regulates nociception and pain at the level of the primary nociceptor or spinal cord. Therefore, we sought to better understand FMRP expression in the human DRG and spinal cord using immunostaining in organ donor tissues. We find that FMRP is highly expressed in DRG and spinal neuron subsets with substantia gelatinosa exhibiting the most abundant immunoreactivity in spinal synaptic fields. Here, it is expressed in nociceptor axons. FMRP puncta colocalized with Nav1.7 and TRPV1 receptor signals suggesting a pool of axoplasmic FMRP localizes to plasma membrane-associated loci in these branches. Interestingly, FMRP puncta exhibited notable colocalization with calcitonin gene-related peptide (CGRP) immunoreactivity selectively in female spinal cord. Our results support a regulatory role for FMRP in human nociceptor axons of the dorsal horn and implicate it in the sex dimorphic actions of CGRP signaling in nociceptive sensitization and chronic pain.
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Affiliation(s)
- Molly E Mitchell
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Lauren C Cook
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Stephanie Shiers
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Diana Tavares-Ferreira
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Armen N Akopian
- Department of Endodontics, UT Health San Antonio, San Antonio, Texas, USA
| | - Gregory Dussor
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
| | - Theodore J Price
- Center for Advanced Pain Studies, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas, USA
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6
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Deng PY, Avraham O, Cavalli V, Klyachko VA. Hyperexcitability of Sensory Neurons in Fragile X Mouse Model. Front Mol Neurosci 2022; 14:796053. [PMID: 35002623 PMCID: PMC8727524 DOI: 10.3389/fnmol.2021.796053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/17/2021] [Indexed: 01/18/2023] Open
Abstract
Sensory hypersensitivity and somatosensory deficits represent the core symptoms of Fragile X syndrome (FXS). These alterations are believed to arise from changes in cortical sensory processing, while potential deficits in the function of peripheral sensory neurons residing in dorsal root ganglia remain unexplored. We found that peripheral sensory neurons exhibit pronounced hyperexcitability in Fmr1 KO mice, manifested by markedly increased action potential (AP) firing rate and decreased threshold. Unlike excitability changes found in many central neurons, no significant changes were observed in AP rising and falling time, peak potential, amplitude, or duration. Sensory neuron hyperexcitability was caused primarily by increased input resistance, without changes in cell capacitance or resting membrane potential. Analyses of the underlying mechanisms revealed reduced activity of HCN channels and reduced expression of HCN1 and HCN4 in Fmr1 KO compared to WT. A selective HCN channel blocker abolished differences in all measures of sensory neuron excitability between WT and Fmr1 KO neurons. These results reveal a hyperexcitable state of peripheral sensory neurons in Fmr1 KO mice caused by dysfunction of HCN channels. In addition to the intrinsic neuronal dysfunction, the accompanying paper examines deficits in sensory neuron association/communication with their enveloping satellite glial cells, suggesting contributions from both neuronal intrinsic and extrinsic mechanisms to sensory dysfunction in the FXS mouse model.
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Affiliation(s)
- Pan-Yue Deng
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Oshri Avraham
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Valeria Cavalli
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States.,Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States.,Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Vitaly A Klyachko
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, United States.,Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States
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7
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Yang Y, Zhao J, Li Y, Li X, Chen X, Feng Z. Fragile X mental retardation protein-regulated proinflammatory cytokine expression in the spinal cord contributes to the pathogenesis of inflammatory pain induced by complete Freund's adjuvant. J Neurochem 2021; 159:512-524. [PMID: 34338322 DOI: 10.1111/jnc.15485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 07/18/2021] [Accepted: 07/26/2021] [Indexed: 11/25/2022]
Abstract
Studies have verified that Fragile X mental retardation protein (FMRP), an RNA-binding protein, plays a potential role in the pathogenesis of formalin- and (RS)-3,5-dihydroxyphenylglycine (DHPG)-induced abnormal pain sensations. However, the role of FMRP in inflammatory pain has not been reported. Here, we showed an increase in FMRP expression in the spinal dorsal horn (SDH) in a rat model of inflammatory pain induced by complete Freund's adjuvant (CFA). Double immunofluorescence staining revealed that FMRP was mainly expressed in spinal neurons and colocalized with proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)]. After consecutive intrathecal injection of fragile X mental retardation 1 (Fmr1) small interfering RNA (siRNA) for 3 days post-CFA injection, FMRP expression in the SDH was reduced, and CFA-induced hyperalgesia was decreased. In addition, the CFA-induced increase in spinal TNF-α and IL-6 production was significantly suppressed by intrathecal administration of Fmr1 siRNA. Together, these results suggest that FMRP regulates TNF-α and IL-6 levels in the SDH and plays an important role in inflammatory pain.
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Affiliation(s)
- Yixin Yang
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine.,Department of Anesthesiology, Ningbo City First Hospital, Ningbo, Zhejiang, China
| | - Jinsong Zhao
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine.,Department of Anesthesiology, Ningbo NO.6 Hospital, Ningbo, Zhejiang, China
| | - Yunze Li
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine
| | - Xiangyao Li
- Institute of Neuroscience, Key Laboratory of Medical Neurobiology, Ministry of Health of China, School of Medicine, Zhejiang University
| | - Xiaowei Chen
- Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, China
| | - Zhiying Feng
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine
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8
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Johnson D, Santos E, Kim K, Ponzini MD, McLennan YA, Schneider A, Tassone F, Hagerman RJ. Increased Pain Symptomatology Among Females vs. Males With Fragile X-Associated Tremor/Ataxia Syndrome. Front Psychiatry 2021; 12:762915. [PMID: 35126193 PMCID: PMC8811376 DOI: 10.3389/fpsyt.2021.762915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 12/27/2021] [Indexed: 12/12/2022] Open
Abstract
Individuals with the fragile X premutation report symptoms of chronic pain from multiple systems, have increased incidence of comorbid conditions where pain is a prominent feature, and pathophysiology that supports disrupted pain regulation, inflammation, and energy imbalance. Less is known about how pain manifests for the subpopulation of carriers that develop the motor and cognitive changes of fragile X-associated tremor and ataxia syndrome (FXTAS), and how pain may differ between men and women. We gathered data collected from 104 males and females with FXTAS related to chronic pain, comorbid conditions related to pain, and medications used for pain control to further explore the types of pain experienced and to better characterize how individuals with the fragile X premutation experience pain sensation across genders. We found that women experience significantly more pain symptoms than men, particularly allodynia (20 vs. 2.0%, p = 0.008), peripheral neuropathy pain (43.9 vs. 25.4%, p = 0.0488), migraine (43.9 vs. 14.5%, p = 0.0008), fibromyalgia (26.8 vs. 0%, p = 0.0071) and back pain (48.5 vs. 23.4%, p = 0.008). We found onset of peripheral neuropathy predicts the onset of ataxia (β = 0.63 ± 0.25, p = 0.019) and tremor (β = 0.56 ± 0.17, p = 0.004) across gender. Women also report significantly more anxiety (82.9 vs. 39.7%, p < 0.001), which has implications for ideal pain treatment. These pain symptoms need to be recognized in the medical history and treated appropriately, with consideration for overlapping comorbidities.
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Affiliation(s)
- Devon Johnson
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Ellery Santos
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Kyoungmi Kim
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States.,Division of Biostatistics, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Matthew D Ponzini
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States.,Division of Biostatistics, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Yingratana A McLennan
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States.,Department of Pediatrics, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States.,Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders Institute, School of Medicine, University of California, Davis, Davis, CA, United States.,Department of Pediatrics, School of Medicine, University of California, Davis, Davis, CA, United States
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9
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Shukla TN, Song J, Campbell ZT. Molecular entrapment by RNA: an emerging tool for disrupting protein-RNA interactions in vivo. RNA Biol 2020; 17:417-424. [PMID: 31957541 PMCID: PMC7237136 DOI: 10.1080/15476286.2020.1717059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 12/09/2019] [Accepted: 01/12/2020] [Indexed: 10/25/2022] Open
Abstract
mRNA function is controlled by RNA-binding proteins. The specificity of RNA-binding factors for their targets is critical in that it enables all subsequent regulation. Despite widespread recognition of the pervasive role RNA-binding proteins play in development and disease, they remain challenging to target with small molecules. A renaissance in RNA therapeutics has led to the identification of modifications that substantially increase RNA stability. When combined with information regarding specificity, a new class of oligonucleotide mimics has emerged as a means to competitively disrupt the regulation of endogenous substrates. These decoys have been used to inhibit RNA-binding proteins in living animals. Decoys will likely provide new insights into the expansive roles of RNA-binding proteins in biology and disease. Here, we describe examples where they have been used and discuss how they could be applied to new targets.
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Affiliation(s)
- Tarjani N. Shukla
- The Department of Biological Sciences, University of Texas-Dallas, Richardson, TX, USA
| | - Jane Song
- The Department of Biological Sciences, University of Texas-Dallas, Richardson, TX, USA
| | - Zachary T. Campbell
- The Department of Biological Sciences, University of Texas-Dallas, Richardson, TX, USA
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10
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Orefice LL, Mosko JR, Morency DT, Wells MF, Tasnim A, Mozeika SM, Ye M, Chirila AM, Emanuel AJ, Rankin G, Fame RM, Lehtinen MK, Feng G, Ginty DD. Targeting Peripheral Somatosensory Neurons to Improve Tactile-Related Phenotypes in ASD Models. Cell 2019; 178:867-886.e24. [PMID: 31398341 PMCID: PMC6704376 DOI: 10.1016/j.cell.2019.07.024] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/06/2019] [Accepted: 07/11/2019] [Indexed: 12/23/2022]
Abstract
Somatosensory over-reactivity is common among patients with autism spectrum disorders (ASDs) and is hypothesized to contribute to core ASD behaviors. However, effective treatments for sensory over-reactivity and ASDs are lacking. We found distinct somatosensory neuron pathophysiological mechanisms underlie tactile abnormalities in different ASD mouse models and contribute to some ASD-related behaviors. Developmental loss of ASD-associated genes Shank3 or Mecp2 in peripheral mechanosensory neurons leads to region-specific brain abnormalities, revealing links between developmental somatosensory over-reactivity and the genesis of aberrant behaviors. Moreover, acute treatment with a peripherally restricted GABAA receptor agonist that acts directly on mechanosensory neurons reduced tactile over-reactivity in six distinct ASD models. Chronic treatment of Mecp2 and Shank3 mutant mice improved body condition, some brain abnormalities, anxiety-like behaviors, and some social impairments but not memory impairments, motor deficits, or overgrooming. Our findings reveal a potential therapeutic strategy targeting peripheral mechanosensory neurons to treat tactile over-reactivity and select ASD-related behaviors.
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Affiliation(s)
- Lauren L Orefice
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Jacqueline R Mosko
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Danielle T Morency
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Michael F Wells
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, USA
| | - Aniqa Tasnim
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Shawn M Mozeika
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Mengchen Ye
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Anda M Chirila
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Alan J Emanuel
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Genelle Rankin
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA
| | - Ryann M Fame
- Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Maria K Lehtinen
- Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Guoping Feng
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139, USA
| | - David D Ginty
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
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11
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Abstract
Nociceptors and neurons in the central nervous system (CNS) that receive nociceptive input show remarkable plasticity in response to injury. This plasticity is thought to underlie the development of chronic pain states. Hence, further understanding of the molecular mechanisms driving and maintaining this plasticity has the potential to lead to novel therapeutic approaches for the treatment of chronic pain states. An important concept in pain plasticity is the presence and persistence of "hyperalgesic priming." This priming arises from an initial injury and results in a remarkable susceptibility to normally subthreshold noxious inputs causing a prolonged pain state in primed animals. Here we describe our current understanding of how this priming is manifested through changes in signaling in the primary nociceptor as well as through memory like alterations at CNS synapses. Moreover, we discuss how commonly utilized analgesics, such as opioids, enhance priming therefore potentially contributing to the development of persistent pain states. Finally we highlight where these priming models draw parallels to common human chronic pain conditions. Collectively, these advances in our understanding of pain plasticity reveal a variety of targets for therapeutic intervention with the potential to reverse rather than palliate chronic pain states.
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Affiliation(s)
- Ram Kandasamy
- Department of Pharmacology, The University of Arizona, Tucson, AZ, 85721, USA
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12
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Melemedjian OK, Khoutorsky A. Translational control of chronic pain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 131:185-213. [PMID: 25744674 DOI: 10.1016/bs.pmbts.2014.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pain is a crucial physiological response to injury and pathologies. The development and maintenance of pain requires the expression of novel genes. The expression of such genes occurs in highly regulated and orchestrated manner where protein translation provides an exquisite temporal and spatial fidelity within the axons and dendrites of neurons. Signaling pathways that regulate local translation are activated by cytokines, neurotrophic factors, or neurotransmitters, which are released either due to tissue damage or neuronal activity. In recent years, the ERK and mTOR pathways have been demonstrated to be central in regulating local translation in neurons of both the peripheral and central nervous systems in diverse models of chronic pain. The ERK and mTOR pathways converge onto the cap-dependent translational machinery that regulates genes essential for the development of nociceptive sensitization. Moreover, inhibition of these pathways has proved to be effective in normalizing the biochemical changes and the associated pain in various preclinical models.
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Affiliation(s)
- Ohannes K Melemedjian
- Department of Neural and Pain Sciences, School of Dentistry, University of Maryland, Baltimore, Maryland, USA.
| | - Arkady Khoutorsky
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montréal, Quebec, Canada
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13
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Price TJ, Inyang KE. Commonalities between pain and memory mechanisms and their meaning for understanding chronic pain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 131:409-34. [PMID: 25744681 DOI: 10.1016/bs.pmbts.2014.11.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Pain sensing neurons in the periphery (called nociceptors) and the central neurons that receive their projections show remarkable plasticity following injury. This plasticity results in amplification of pain signaling that is now understood to be crucial for the recovery and survival of organisms following injury. These same plasticity mechanisms may drive a transition to a nonadaptive chronic pain state if they fail to resolve following the termination of the healing process. Remarkable advances have been achieved in the past two decades in understanding the molecular mechanisms that underlie pain plasticity following injury. The mechanisms bear a striking resemblance to molecular mechanisms involved in learning and memory processes in other brain regions, including the hippocampus and cerebral cortex. Here those mechanisms, their commonalities and subtle differences, will be highlighted and their role in causing chronic pain will be discussed. Arising from these data is the striking argument that chronic pain is a disease of the nervous system, which distinguishes this phenomena from acute pain that is frequently a symptom alerting the organism to injury. This argument has important implications for the development of disease modifying therapeutics.
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Affiliation(s)
- Theodore J Price
- Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA.
| | - Kufreobong E Inyang
- Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA
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Sidorov MS, Auerbach BD, Bear MF. Fragile X mental retardation protein and synaptic plasticity. Mol Brain 2013; 6:15. [PMID: 23566911 PMCID: PMC3636002 DOI: 10.1186/1756-6606-6-15] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/25/2013] [Indexed: 12/20/2022] Open
Abstract
Loss of the translational repressor FMRP causes Fragile X syndrome. In healthy neurons, FMRP modulates the local translation of numerous synaptic proteins. Synthesis of these proteins is required for the maintenance and regulation of long-lasting changes in synaptic strength. In this role as a translational inhibitor, FMRP exerts profound effects on synaptic plasticity.
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Affiliation(s)
- Michael S Sidorov
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 46-3301, USA
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