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Hamilton HL, Akther M, Anis S, Colwell CB, Vargas MR, Pehar M. Nicotinamide Adenine Dinucleotide Precursor Supplementation Modulates Neurite Complexity and Survival in Motor Neurons from Amyotrophic Lateral Sclerosis Models. Antioxid Redox Signal 2024. [PMID: 38504592 DOI: 10.1089/ars.2023.0360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Aims: Increasing nicotinamide adenine dinucleotide (NAD+) availability has been proposed as a therapeutic approach to prevent neurodegeneration in amyotrophic lateral sclerosis (ALS). Accordingly, NAD+ precursor supplementation appears to exert neuroprotective effects in ALS patients and mouse models. The mechanisms mediating neuroprotection remain uncertain but could involve changes in multiple cell types. We investigated a potential direct effect of the NAD+ precursor nicotinamide mononucleotide (NMN) on the health of cultured induced pluripotent stem cell (iPSC)-derived human motor neurons and in motor neurons isolated from two ALS mouse models, that is, mice overexpressing wild-type transactive response DNA binding protein-43 (TDP-43) or the ALS-linked human superoxide dismutase 1 with the G93A mutation (hSOD1G93A). Results: NMN treatment increased the complexity of neuronal processes in motor neurons isolated from both mouse models and in iPSC-derived human motor neurons. In addition, NMN prevented neuronal death induced by trophic factor deprivation. In mouse and human motor neurons expressing ALS-linked mutant superoxide dismutase 1, NMN induced an increase in glutathione levels, but this effect was not observed in nontransgenic or TDP-43 overexpressing motor neurons. In contrast, NMN treatment normalized the TDP-43 cytoplasmic mislocalization induced by its overexpression. Innovation: NMN can directly act on motor neurons to increase the growth and complexity of neuronal processes and prevent the death induced by trophic factor deprivation. Conclusion: Our results support a direct beneficial effect of NAD+ precursor supplementation on the maintenance of the neuritic arbor in motor neurons. Importantly, this was observed in motor neurons isolated from two different ALS models, with and without involvement of TDP-43 pathology, supporting its therapeutic potential in sporadic and familial ALS.
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Affiliation(s)
- Haylee L Hamilton
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Mahbuba Akther
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Shaheer Anis
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Christopher B Colwell
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Marcelo R Vargas
- Department of Neurology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Mariana Pehar
- Division of Geriatrics and Gerontology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Geriatric Research Education Clinical Center, Veterans Affairs Medical Center, Madison, Wisconsin, USA
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Fogarty MJ. Dendritic morphology of motor neurons and interneurons within the compact, semicompact, and loose formations of the rat nucleus ambiguus. Front Cell Neurosci 2024; 18:1409974. [PMID: 38933178 PMCID: PMC11199410 DOI: 10.3389/fncel.2024.1409974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 05/27/2024] [Indexed: 06/28/2024] Open
Abstract
Introduction Motor neurons (MNs) within the nucleus ambiguus innervate the skeletal muscles of the larynx, pharynx, and oesophagus. These muscles are activated during vocalisation and swallowing and must be coordinated with several respiratory and other behaviours. Despite many studies evaluating the projections and orientation of MNs within the nucleus ambiguus, there is no quantitative information regarding the dendritic arbours of MNs residing in the compact, and semicompact/loose formations of the nucleus ambiguus.. Methods In female and male Fischer 344 rats, we evaluated MN number using Nissl staining, and MN and non-MN dendritic morphology using Golgi-Cox impregnation Brightfield imaging of transverse Nissl sections (15 μm) were taken to stereologically assess the number of nucleus ambiguus MNs within the compact and semicompact/loose formations. Pseudo-confocal imaging of Golgi-impregnated neurons within the nucleus ambiguus (sectioned transversely at 180 μm) was traced in 3D to determine dendritic arbourisation. Results We found a greater abundance of MNs within the compact than the semicompact/loose formations. Dendritic lengths, complexity, and convex hull surface areas were greatest in MNs of the semicompact/loose formation, with compact formation MNs being smaller. MNs from both regions were larger than non-MNs reconstructed within the nucleus ambiguus. Conclusion Adding HBLS to the diet could be a potentially effective strategy to improve horses' health.
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Affiliation(s)
- Matthew J. Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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Arnold FJ, Putka AF, Raychaudhuri U, Hsu S, Bedlack RS, Bennett CL, La Spada AR. Revisiting Glutamate Excitotoxicity in Amyotrophic Lateral Sclerosis and Age-Related Neurodegeneration. Int J Mol Sci 2024; 25:5587. [PMID: 38891774 PMCID: PMC11171854 DOI: 10.3390/ijms25115587] [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: 04/30/2024] [Revised: 05/17/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disorder. While there are five FDA-approved drugs for treating this disease, each has only modest benefits. To design new and more effective therapies for ALS, particularly for sporadic ALS of unknown and diverse etiologies, we must identify key, convergent mechanisms of disease pathogenesis. This review focuses on the origin and effects of glutamate-mediated excitotoxicity in ALS (the cortical hyperexcitability hypothesis), in which increased glutamatergic signaling causes motor neurons to become hyperexcitable and eventually die. We characterize both primary and secondary contributions to excitotoxicity, referring to processes taking place at the synapse and within the cell, respectively. 'Primary pathways' include upregulation of calcium-permeable AMPA receptors, dysfunction of the EAAT2 astrocytic glutamate transporter, increased release of glutamate from the presynaptic terminal, and reduced inhibition by cortical interneurons-all of which have been observed in ALS patients and model systems. 'Secondary pathways' include changes to mitochondrial morphology and function, increased production of reactive oxygen species, and endoplasmic reticulum (ER) stress. By identifying key targets in the excitotoxicity cascade, we emphasize the importance of this pathway in the pathogenesis of ALS and suggest that intervening in this pathway could be effective for developing therapies for this disease.
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Affiliation(s)
- Frederick J. Arnold
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA 92617, USA
- Department of Neurology, Duke University School of Medicine, Durham, NC 27710, USA; (A.F.P.)
| | - Alexandra F. Putka
- Department of Neurology, Duke University School of Medicine, Durham, NC 27710, USA; (A.F.P.)
| | - Urmimala Raychaudhuri
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA 92617, USA
| | - Solomon Hsu
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA 92617, USA
| | - Richard S. Bedlack
- Department of Neurology, Duke University School of Medicine, Durham, NC 27710, USA; (A.F.P.)
| | - Craig L. Bennett
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA 92617, USA
- Department of Neurology, University of California Irvine, Irvine, CA 92617, USA
| | - Albert R. La Spada
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA 92617, USA
- Department of Neurology, Duke University School of Medicine, Durham, NC 27710, USA; (A.F.P.)
- Department of Neurology, University of California Irvine, Irvine, CA 92617, USA
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92617, USA
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA 92697, USA
- UCI Center for Neurotherapeutics, University of California Irvine, Irvine, CA 92697, USA
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Odierna GL, Vucic S, Dyer M, Dickson T, Woodhouse A, Blizzard C. How do we get from hyperexcitability to excitotoxicity in amyotrophic lateral sclerosis? Brain 2024; 147:1610-1621. [PMID: 38408864 PMCID: PMC11068114 DOI: 10.1093/brain/awae039] [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: 07/17/2023] [Revised: 11/15/2023] [Accepted: 12/10/2023] [Indexed: 02/28/2024] Open
Abstract
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease that, at present, has no effective cure. Evidence of increased circulating glutamate and hyperexcitability of the motor cortex in patients with amyotrophic lateral sclerosis have provided an empirical support base for the 'dying forward' excitotoxicity hypothesis. The hypothesis postulates that increased activation of upper motor neurons spreads pathology to lower motor neurons in the spinal cord in the form of excessive glutamate release, which triggers excitotoxic processes. Many clinical trials have focused on therapies that target excitotoxicity via dampening neuronal activation, but not all are effective. As such, there is a growing tension between the rising tide of evidence for the 'dying forward' excitotoxicity hypothesis and the failure of therapies that target neuronal activation. One possible solution to these contradictory outcomes is that our interpretation of the current evidence requires revision in the context of appreciating the complexity of the nervous system and the limitations of the neurobiological assays we use to study it. In this review we provide an evaluation of evidence relevant to the 'dying forward' excitotoxicity hypothesis and by doing so, identify key gaps in our knowledge that need to be addressed. We hope to provide a road map from hyperexcitability to excitotoxicity so that we can better develop therapies for patients suffering from amyotrophic lateral sclerosis. We conclude that studies of upper motor neuron activity and their synaptic output will play a decisive role in the future of amyotrophic lateral sclerosis therapy.
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Affiliation(s)
- G Lorenzo Odierna
- Tasmanian School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
| | - Steve Vucic
- Brain and Nerve Research Center, The University of Sydney, Sydney 2050, Australia
| | - Marcus Dyer
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
- Department of Pharmaceutical and Pharmacological Sciences, Center for Neurosciences, Vrije Universiteit Brussel (VUB), 1090 Brussels, Belgium
| | - Tracey Dickson
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
| | - Adele Woodhouse
- The Wicking Dementia Centre, University of Tasmania, Hobart, TAS 7000, Australia
| | - Catherine Blizzard
- Tasmanian School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
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Costa-Pinto S, Gonçalves-Ribeiro J, Tedim-Moreira J, Socodato R, Relvas JB, Sebastião AM, Vaz SH. Communication defects with astroglia contribute to early impairments in the motor cortex plasticity of SOD1 G93A mice. Neurobiol Dis 2024; 193:106435. [PMID: 38336279 DOI: 10.1016/j.nbd.2024.106435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 02/06/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease, involving the selective degeneration of cortical upper synapses in the primary motor cortex (M1). Excitotoxicity in ALS occurs due to an imbalance between excitation and inhibition, closely linked to the loss/gain of astrocytic function. Using the ALS SOD1G93A mice, we investigated the astrocytic contribution for the electrophysiological alterations observed in the M1 of SOD1G93A mice, throughout disease progression. Results showed that astrocytes are involved in synaptic dysfunction observed in presymptomatic SOD1G93A mice, since astrocytic glutamate transport currents are diminished and pharmacological inhibition of astrocytes only impaired long-term potentiation and basal transmission in wild-type mice. Proteomic analysis revealed major differences in neuronal transmission, metabolism, and immune system in upper synapses, confirming early communication deficits between neurons and astroglia. These results provide valuable insights into the early impact of upper synapses in ALS and the lack of supportive functions of cortical astrocytes, highlighting the possibility of manipulating astrocytes to improve synaptic function.
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Affiliation(s)
- Sara Costa-Pinto
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon 1649-028, Portugal
| | - Joana Gonçalves-Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon 1649-028, Portugal
| | - Joana Tedim-Moreira
- Instituto de Investigação e Inovação em Saúde and Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto 4200-135, Portugal; Department of Biomedicine, Faculty of Medicine, University of Porto, Porto 4200-135, Portugal
| | - Renato Socodato
- Instituto de Investigação e Inovação em Saúde and Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto 4200-135, Portugal
| | - João B Relvas
- Instituto de Investigação e Inovação em Saúde and Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto 4200-135, Portugal; Department of Biomedicine, Faculty of Medicine, University of Porto, Porto 4200-135, Portugal
| | - Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon 1649-028, Portugal
| | - Sandra H Vaz
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisbon, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon 1649-028, Portugal.
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Cao Y, Wu Y, Dong Q, Huang N, Zou Z, Chen H. Neurite orientation dispersion and density imaging quantifies microstructural impairment in the thalamus and its connectivity in amyotrophic lateral sclerosis. CNS Neurosci Ther 2024; 30:e14616. [PMID: 38334027 PMCID: PMC10853891 DOI: 10.1111/cns.14616] [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: 09/11/2023] [Revised: 12/13/2023] [Accepted: 01/11/2024] [Indexed: 02/10/2024] Open
Abstract
AIMS To evaluate microstructural impairment in the thalamus and thalamocortical connectivity using neurite orientation dispersion and density imaging (NODDI) in amyotrophic lateral sclerosis (ALS). METHODS This study included 47 healthy controls and 43 ALS patients, whose structural and diffusion-weighted data were collected. We used state-of-the-art parallel transport tractography to identify thalamocortical pathways in individual spaces. Thalamus was then parcellated into six subregions based on its connectivity pattern with the priori defined cortical (i.e., prefrontal/motor/somatosensory/temporal/posterior-parietal/occipital) regions. For each of the thalamic and cortical subregions and thalamo-cortical tracts, we compared the following NODDI metrics between groups: orientation dispersion index (ODI), neurite density index (NDI), and isotropic volume fraction (ISO). We also used these metrics to conduct receiver operating characteristic curve (ROC) analyses and Spearman correlation. RESULTS In ALS patients, we found decreased ODI and increased ISO in the thalamic subregion connecting the left motor cortex and other extramotor (e.g., somatosensory and occipital) cortex (Bonferroni-corrected p < 0.05). NDI decreased in the bilateral thalamo-motor and thalamo-somatosensory tracts and in the right thalamo-posterior-parietal and thalamo-occipital tracts (Bonferroni-corrected p < 0.05). NDI reduction in the bilateral thalamo-motor tract (p = 0.017 and 0.009) and left thalamo-somatosensory tract (p = 0.029) was correlated with disease severity. In thalamo-cortical tracts, NDI yielded a higher effect size during between-group comparisons and a greater area under ROC (p < 0.05) compared with conventional diffusion tensor imaging metrics. CONCLUSIONS Microstructural impairment in the thalamus and thalamocortical connectivity is the hallmark of ALS. NODDI improved the detection of disrupted thalamo-cortical connectivity in ALS.
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Affiliation(s)
- Yun‐Bin Cao
- Department of RadiologyFujian Medical University Union HospitalFuzhouChina
| | - Ye Wu
- School of Computer Science and EngineeringNanjing University of Science and TechnologyNanjingChina
| | - Qiu‐Yi Dong
- Department of RadiologyFujian Medical University Union HospitalFuzhouChina
| | - Nao‐Xin Huang
- Department of RadiologyFujian Medical University Union HospitalFuzhouChina
| | - Zhang‐Yu Zou
- Department of NeurologyFujian Medical University Union HospitalFuzhouChina
| | - Hua‐Jun Chen
- Department of RadiologyFujian Medical University Union HospitalFuzhouChina
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7
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Anderson JA, Rashidi-Ranjbar N, Nazeri A, Chad JA, Zhukovsky P, Mulsant BH, Herrmann N, Mah L, Flint AJ, Fischer CE, Pollock BG, Rajji TK, Voineskos AN. Age-Related Alterations in Gray Matter Microstructure in Older People With Remitted Major Depression at Risk for Dementia. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2024; 4:374-384. [PMID: 38298786 PMCID: PMC10829634 DOI: 10.1016/j.bpsgos.2023.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/15/2023] [Accepted: 08/27/2023] [Indexed: 02/02/2024] Open
Abstract
Background Major depressive disorder (MDD) in late life is a risk factor for mild cognitive impairment (MCI) and Alzheimer's disease. However, studies of gray matter changes have produced varied estimates of which structures are implicated in MDD and dementia. Changes in gray matter volume and cortical thickness are macrostructural measures for the microstructural processes of free water accumulation and dendritic spine loss. Methods We conducted multishell diffusion imaging to assess gray matter microstructure in 244 older adults with remitted MDD (n = 44), MCI (n = 115), remitted MDD+MCI (n = 61), or without psychiatric disorders or cognitive impairment (healthy control participants; n = 24). We estimated measures related to neurite density, orientation dispersion, and free water (isotropic volume fraction) using a biophysically plausible model (neurite orientation dispersion and density imaging). Results Results showed that increasing age was correlated with an increase in isotropic volume fraction and a decrease in orientation dispersion index, which is consistent with neuropathology dendritic loss. In addition, this relationship between age and increased isotropic volume fraction was more disrupted in the MCI group than in the remitted MDD or healthy control groups. However, the association between age and orientation dispersion index was similar for all 3 groups. Conclusions The findings suggest that the neurite orientation dispersion and density imaging measures could be used to identify biological risk factors for Alzheimer's disease, signifying both conventional neurodegeneration observed with MCI and dendritic loss seen in MDD.
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Affiliation(s)
- John A.E. Anderson
- Department of Cognitive Science, Carleton University, Ottawa, Ontario, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Neda Rashidi-Ranjbar
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, Ontario, Canada
| | - Arash Nazeri
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri (AN)
| | - Jordan A. Chad
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Baycrest Health Sciences, Toronto, Ontario, Canada
| | - Peter Zhukovsky
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Benoit H. Mulsant
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Nathan Herrmann
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Health Sciences Centre, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Linda Mah
- Baycrest Health Sciences, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Alastair J. Flint
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Centre for Mental Health, University Health Network, Toronto, Ontario, Canada
| | - Corinne E. Fischer
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Bruce G. Pollock
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Tarek K. Rajji
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Toronto Dementia Research Alliance, University of Toronto, Toronto, Ontario, Canada
| | - Aristotle N. Voineskos
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - PACt-MD Study Group
- Department of Cognitive Science, Carleton University, Ottawa, Ontario, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, Ontario, Canada
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri (AN)
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Baycrest Health Sciences, Toronto, Ontario, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Health Sciences Centre, Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Centre for Mental Health, University Health Network, Toronto, Ontario, Canada
- Toronto Dementia Research Alliance, University of Toronto, Toronto, Ontario, Canada
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Pisciottani A, Croci L, Lauria F, Marullo C, Savino E, Ambrosi A, Podini P, Marchioretto M, Casoni F, Cremona O, Taverna S, Quattrini A, Cioni JM, Viero G, Codazzi F, Consalez GG. Neuronal models of TDP-43 proteinopathy display reduced axonal translation, increased oxidative stress, and defective exocytosis. Front Cell Neurosci 2023; 17:1253543. [PMID: 38026702 PMCID: PMC10679756 DOI: 10.3389/fncel.2023.1253543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/13/2023] [Indexed: 12/01/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, lethal neurodegenerative disease mostly affecting people around 50-60 years of age. TDP-43, an RNA-binding protein involved in pre-mRNA splicing and controlling mRNA stability and translation, forms neuronal cytoplasmic inclusions in an overwhelming majority of ALS patients, a phenomenon referred to as TDP-43 proteinopathy. These cytoplasmic aggregates disrupt mRNA transport and localization. The axon, like dendrites, is a site of mRNA translation, permitting the local synthesis of selected proteins. This is especially relevant in upper and lower motor neurons, whose axon spans long distances, likely accentuating their susceptibility to ALS-related noxae. In this work we have generated and characterized two cellular models, consisting of virtually pure populations of primary mouse cortical neurons expressing a human TDP-43 fusion protein, wt or carrying an ALS mutation. Both forms facilitate cytoplasmic aggregate formation, unlike the corresponding native proteins, giving rise to bona fide primary culture models of TDP-43 proteinopathy. Neurons expressing TDP-43 fusion proteins exhibit a global impairment in axonal protein synthesis, an increase in oxidative stress, and defects in presynaptic function and electrical activity. These changes correlate with deregulation of axonal levels of polysome-engaged mRNAs playing relevant roles in the same processes. Our data support the emerging notion that deregulation of mRNA metabolism and of axonal mRNA transport may trigger the dying-back neuropathy that initiates motor neuron degeneration in ALS.
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Affiliation(s)
- Alessandra Pisciottani
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Laura Croci
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Fabio Lauria
- Institute of Biophysics, CNR Unit at Trento, Povo, Italy
| | - Chiara Marullo
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Elisa Savino
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Alessandro Ambrosi
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Paola Podini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | | | - Filippo Casoni
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Ottavio Cremona
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
| | - Stefano Taverna
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Angelo Quattrini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Jean-Michel Cioni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | | | - Franca Codazzi
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - G. Giacomo Consalez
- Faculty of Medicine and Surgery, Università Vita-Salute San Raffaele, Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
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9
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Dyer MS, Odierna GL, Clark RM, Woodhouse A, Blizzard CA. Synaptic remodeling follows upper motor neuron hyperexcitability in a rodent model of TDP-43. Front Cell Neurosci 2023; 17:1274979. [PMID: 37941604 PMCID: PMC10628445 DOI: 10.3389/fncel.2023.1274979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 10/05/2023] [Indexed: 11/10/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is an incurable disease characterized by relentlessly progressive degeneration of the corticomotor system. Cortical hyperexcitability has been identified as an early pre-symptomatic biomarker of ALS. This suggests that hyperexcitability occurs upstream in the ALS pathological cascade and may even be part of the mechanism that drives development of symptoms or loss of motor neurons in the spinal cord. However, many studies also indicate a loss to the synaptic machinery that mediates synaptic input which raises the question of which is the driver of disease, and which is a homeostatic response. Herein, we used an inducible mouse model of TDP-43 mediated ALS that permits for the construction of detailed phenotypic timelines. Our work comprehensively describes the relationship between intrinsic hyperexcitability and altered synaptic input onto motor cortical layer 5 pyramidal neurons over time. As a result, we have constructed the most complete timeline of electrophysiological changes following induction of TDP-43 dysfunction in the motor cortex. We report that intrinsic hyperexcitability of layer 5 pyramidal neurons precedes changes to excitatory synaptic connections, which manifest as an overall loss of inputs onto layer 5 pyramidal neurons. This finding highlights the importance of hyperexcitability as a primary mechanism of ALS and re-contextualizes synaptic changes as possibly representing secondary adaptive responses. Recognition of the relationship between intrinsic hyperexcitability and reduced excitatory synaptic input has important implications for the development of useful therapies against ALS. Novel strategies will need to be developed that target neuronal output by managing excitability against synapses separately.
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Affiliation(s)
- Marcus S. Dyer
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
- Department of Pharmaceutical and Pharmacological Sciences, Center for Neurosciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - G. Lorenzo Odierna
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Rosemary M. Clark
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Adele Woodhouse
- Wicking Dementia Research and Education Centre, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Catherine A. Blizzard
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
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10
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Gold ND, Mallard AJ, Hermann JC, Zeifman RJ, Pagni BA, Bogenschutz MP, Ross S. Exploring the Potential Utility of Psychedelic Therapy for Patients With Amyotrophic Lateral Sclerosis. J Palliat Med 2023; 26:1408-1418. [PMID: 37167080 DOI: 10.1089/jpm.2022.0604] [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] [Indexed: 05/13/2023] Open
Abstract
Background: Amyotrophic lateral sclerosis (ALS) is an aggressive, terminal neurodegenerative disease that causes death of motor neurons and has an average survival time of 3-4 years. ALS is the most common motor neuron degenerative disease and is increasing in prevalence. There is a pressing need for more effective ALS treatments as available pharmacotherapies do not reverse disease progression or provide substantial clinical benefit. Furthermore, despite psychological distress being highly prevalent in ALS patients, psychological treatments remain understudied. Psychedelics (i.e., serotonergic psychedelics and related compounds like ketamine) have seen a resurgence of research into therapeutic applications for treating a multitude of neuropsychiatric conditions, including psychiatric and existential distress in life-threatening illnesses. Methods: We conducted a narrative review to examine the potential of psychedelic assisted-psychotherapy (PAP) to alleviate psychiatric and psychospiritual distress in ALS. We also discussed the safety of using psychedelics in this population and proposed putative neurobiological mechanisms that may therapeutically intervene on ALS neuropathology. Results: PAP has the potential to treat psychological dimensions and may also intervene on neuropathological dimensions of ALS. Robust improvements in psychiatric and psychospiritual distress from PAP in other populations provide a strong rationale for utilizing this therapy to treat ALS-related psychiatric and existential distress. Furthermore, relevant neuroprotective properties of psychedelics warrant future preclinical trials to investigate this area in ALS models. Conclusion: PAP has the potential to serve as an effective treatment in ALS. Given the lack of effective treatment options, researchers should rigorously explore this therapy for ALS in future trials.
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Affiliation(s)
- Noah D Gold
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
| | - Austin J Mallard
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
| | - Jacob C Hermann
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Richard J Zeifman
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
| | - Broc A Pagni
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
| | - Michael P Bogenschutz
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
| | - Stephen Ross
- Department of Psychiatry, NYU Langone Center for Psychedelic Medicine, NYU Grossman School of Medicine, New York, New York, USA
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11
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Fogarty MJ, Zhan WZ, Simmon VF, Vanderklish PW, Sarraf ST, Sieck GC. Novel regenerative drug, SPG302 promotes functional recovery of diaphragm muscle activity after cervical spinal cord injury. J Physiol 2023; 601:2513-2532. [PMID: 36815402 PMCID: PMC10404468 DOI: 10.1113/jp284004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 02/17/2023] [Indexed: 02/24/2023] Open
Abstract
Spinal cord hemisection at C2 (C2 SH), sparing the dorsal column is widely used to investigate the effects of reduced phrenic motor neuron (PhMN) activation on diaphragm muscle (DIAm) function, with reduced DIAm activity on the injured side during eupnoea. Following C2 SH, recovery of DIAm EMG activity may occur spontaneously over subsequent days/weeks. Various strategies have been effective at improving the incidence and magnitude of DIAm recovery during eupnoea, but little is known about the effects of C2 SH on transdiaphragmatic pressure (Pdi ) during other ventilatory and non-ventilatory behaviours. We employ SPG302, a novel type of pegylated benzothiazole derivative, to assess whether enhancing synaptogenesis (i.e., enhancing spared local connections) will improve the incidence and the magnitude of recovery of DIAm EMG activity and Pdi function 14 days post-C2 SH. In anaesthetised Sprague-Dawley rats, DIAm EMG and Pdi were assessed during eupnoea, hypoxia/hypercapnia and airway occlusion prior to surgery (C2 SH or sham), immediately post-surgery and at 14 days post-surgery. In C2 SH rats, 14 days of DMSO (vehicle) or SPG302 treatments (i.p. injection) occurred. At the terminal experiment, maximum Pdi was evoked by bilateral phrenic nerve stimulation. We show that significant EMG and Pdi deficits are apparent in C2 SH compared with sham rats immediately after surgery. In C2 SH rats treated with SPG302, recovery of eupneic, hypoxia/hypercapnia and occlusion DIAm EMG was enhanced compared with vehicle rats after 14 days. Treatment with SPG302 also ameliorated Pdi deficits following C2 SH. In summary, SPG302 is an exciting new therapy to explore for use in spinal cord injuries. KEY POINTS: Despite advances in our understanding of the effects of cervical hemisection (C2 SH) on diaphragm muscle (DIAm) EMG activity, very little is understood about the impact of C2 SH on the gamut of ventilatory and non-ventilatory transdiaphragmatic pressures (Pdi ). Recovery of DIAm activity following C2 SH is improved using a variety of approaches, but very few pharmaceuticals have been shown to be effective. One way of improving DIAm recovery is to enhance the amount of latent local spared connections onto phrenic motor neurons. A novel pegylated benzothiazole derivative enhances synaptogenesis in a variety of neurodegenerative conditions. Here, using a novel therapeutic SPG302, we show that 14 days of treatment with SPG302 ameliorated DIAm EMG and Pdi deficits compared with vehicle controls. Our results show that SPG302 is a compound with very promising potential for use in improving functional outcomes post-spinal cord injury.
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Affiliation(s)
- Matthew J. Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Wen-Zhi Zhan
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Vincent F. Simmon
- Spinogenix Inc, 4225 Executive Square, Suite 600 La Jolla, California, USA
| | | | - Stella T. Sarraf
- Spinogenix Inc, 4225 Executive Square, Suite 600 La Jolla, California, USA
| | - Gary C. Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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12
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Horio T, Ishikura Y, Ohashi R, Shiina N. Regulation of RNG105/caprin1 dynamics by pathogenic cytoplasmic FUS and TDP-43 in neuronal RNA granules modulates synaptic loss. Heliyon 2023; 9:e17065. [PMID: 37484309 PMCID: PMC10361247 DOI: 10.1016/j.heliyon.2023.e17065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 05/25/2023] [Accepted: 06/06/2023] [Indexed: 07/25/2023] Open
Abstract
In neurodegenerative diseases, the condensation of FUS and TDP-43 with RNA granules in neurons is linked to pathology, including synaptic disorders. However, the effects of FUS and TDP-43 on RNA granule factors remain unclear. Here, using primary cultured neurons from the mouse cerebral cortex, we show that excess cytoplasmic FUS and TDP-43 accumulated in dendritic RNA granules, where they increased the dynamics of a scaffold protein RNG105/caprin1 and dissociated it from the granules. This coincided with reduced levels of mRNA and translation around the granules and synaptic loss in dendrites. These defects were suppressed by non-dissociable RNG105, suggesting that RNG105 dissociation mediated the defects. In contrast to the model where FUS and TDP-43 co-aggregate with RNA granule factors to repress their activity, our findings provide a novel pathogenic mechanism whereby FUS and TDP-43 dissociate RNA scaffold proteins from RNA granules which are required for local translation that regulates synapse formation.
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Affiliation(s)
- Tomoyo Horio
- Laboratory of Neuronal Cell Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
- Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8585, Japan
| | - Yui Ishikura
- Laboratory of Neuronal Cell Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
- Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8585, Japan
| | - Rie Ohashi
- Laboratory of Neuronal Cell Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
- Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8585, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
- Life Science Research Center, University of Toyama, Toyama, Toyama 930-0194, Japan
| | - Nobuyuki Shiina
- Laboratory of Neuronal Cell Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
- Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8585, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
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13
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Li Z. The ALS-Related SynGAP1 Pathogenic Variant Causes Dendritic Spine Loss: Potential Mechanisms of Early-Stage ALS Progression. J Neurosci 2023; 43:2819-2821. [PMID: 37076290 PMCID: PMC10124941 DOI: 10.1523/jneurosci.0099-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 04/21/2023] Open
Affiliation(s)
- Zhanxu Li
- Xiangya School of Medicine, Central South University, Changsha, Hunan 410078, China
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14
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Widagdo J, Udagedara S, Bhembre N, Tan JZA, Neureiter L, Huang J, Anggono V, Lee M. Familial ALS-associated SFPQ variants promote the formation of SFPQ cytoplasmic aggregates in primary neurons. Open Biol 2022; 12:220187. [PMID: 36168806 PMCID: PMC9516340 DOI: 10.1098/rsob.220187] [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] [Indexed: 11/15/2022] Open
Abstract
Splicing factor proline- and glutamine-rich (SFPQ) is a nuclear RNA-binding protein that is involved in a wide range of physiological processes including neuronal development and homeostasis. However, the mislocalization and cytoplasmic aggregation of SFPQ are associated with the pathophysiology of amyotrophic lateral sclerosis (ALS). We have previously reported that zinc mediates SFPQ polymerization and promotes the formation of cytoplasmic aggregates in neurons. Here we characterize two familial ALS (fALS)-associated SFPQ variants, which cause amino acid substitutions in the proximity of the SFPQ zinc-coordinating centre (N533H and L534I). Both mutants display increased zinc-binding affinities, which can be explained by the presence of a second zinc-binding site revealed by the 1.83 Å crystal structure of the human SFPQ L534I mutant. Overexpression of these fALS-associated mutants significantly increases the number of SFPQ cytoplasmic aggregates in primary neurons. Although they do not affect the density of dendritic spines, the presence of SFPQ cytoplasmic aggregates causes a marked reduction in the levels of the GluA1, but not the GluA2 subunit of AMPA-type glutamate receptors on the neuronal surface. Taken together, our data demonstrate that fALS-associated mutations enhance the propensity of SFPQ to bind zinc and form aggregates, leading to the dysregulation of AMPA receptor subunit composition, which may contribute to neuronal dysfunction in ALS.
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Affiliation(s)
- Jocelyn Widagdo
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Saumya Udagedara
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Nishita Bhembre
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jing Zhi Anson Tan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Lara Neureiter
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jie Huang
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Victor Anggono
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Mihwa Lee
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
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15
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Beaubois R, Khoyratee F, Branchereau P, Ikeuchi Y, Levi T. From real-time single to multicompartmental Hodgkin-Huxley neurons on FPGA for bio-hybrid systems. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:1602-1606. [PMID: 36083914 DOI: 10.1109/embc48229.2022.9871176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Modeling biological neural networks has been a field opening to major advances in our understanding of the mechanisms governing the functioning of the brain in normal and pathological conditions. The emergence of real-time neuromorphic platforms has been leading to a rising significance of bio-hybrid experiments as part of the development of neuromorphic biomedical devices such as neuroprosthesis. To provide a new tool for the neurological disorder characterization, we design real-time single and multicompartmental Hodgkin-Huxley neurons on FPGA. These neurons allow biological neural network emulation featuring improved accuracy through compartment modeling and show integration in bio-hybrid system thanks to its real-time dynamics.
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16
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Tang Y, Liu P, Li W, Liu Z, Zhou M, Li J, Yuan Y, Fang L, Wang M, Shen L, Huang Y, Tang B, Wang J, Hu S. Detection of changes in synaptic density in amyotrophic lateral sclerosis patients using 18 F-SynVesT-1 positron-emission tomography. Eur J Neurol 2022; 29:2934-2943. [PMID: 35708508 DOI: 10.1111/ene.15451] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 06/13/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND Synaptic loss is well established as the major correlate of characteristic and consistent pathology in amyotrophic lateral sclerosis (ALS). We aimed to assess the possible discriminant diagnostic value of 18 F-SynVesT-1 positron-emission tomography (PET) as a marker of ALS pathology and investigate whether specific synaptic density signatures are present in ALS with different subtypes. METHODS Twenty-one patients with ALS and 25 healthy controls (HCs) were recruited. All participants underwent 18 F-SynVesT-1-PET. Synaptic density between ALS and HCs and between different ALS subgroups were compared. Correlation between synaptic density and clinical features in ALS was also performed. RESULTS Low uptake distribution was found in the group comprising 21 ALS patients as compared with HCs in the right temporal lobe and the bilateral inferior frontal gyrus, anterior cingulate, and hippocampus-insula region. We also found a low uptake in the bilateral superior temporal gyrus, hippocampus-insula, anterior cingulate and left inferior frontal gyrus in ALS patients with cognitive impairment compared to HCs. Furthermore, compared to spinal-onset ALS, bulbar-onset ALS showed low uptake in the bilateral cingulate gyrus and high uptake in the bilateral superior temporal gyrus and left occipital lobe. No significant result was found in correlation analysis. CONCLUSION This approach may provide a direct measure of synaptic density, and it therefore might represent a potentially useful biomarker for ALS diagnosis, as well as for estimating the cognitive decline and site of onset in ALS. 18 F-SynVesT-1-PET is presently not justified as a routine investigation to detect evidence of brain dysfunction justifying progression in ALS.
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Affiliation(s)
- Yongxiang Tang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Pan Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Wanzhen Li
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Zhen Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Ming Zhou
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Jian Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Yanchun Yuan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Liangjuan Fang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Mengli Wang
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, P. R. China.,Center for Medical Genetics, School of Life Sciences, Central South University
| | - Yiyun Huang
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, P. R. China.,Center for Medical Genetics, School of Life Sciences, Central South University
| | - Junling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, P. R. China.,Center for Medical Genetics, School of Life Sciences, Central South University.,Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China.,Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
| | - Shuo Hu
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan, P. R. China.,Key Laboratory of Biological Nanotechnology of National Health Commission, Xiangya Hospital, Central South University, Changsha, Hunan, China
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17
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Genç B, Jara JH, Sanchez SS, Lagrimas AKB, Gözütok Ö, Koçak N, Zhu Y, Hande Özdinler P. Upper motor neurons are a target for gene therapy and UCHL1 is necessary and sufficient to improve cellular integrity of diseased upper motor neurons. Gene Ther 2022; 29:178-192. [PMID: 34853443 PMCID: PMC9018479 DOI: 10.1038/s41434-021-00303-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/15/2022]
Abstract
There are no effective cures for upper motor neuron (UMN) diseases, such as amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, and hereditary spastic paraplegia. Here, we show UMN loss occurs independent of spinal motor neuron degeneration and that UMNs are indeed effective cellular targets for gene therapy, which offers a potential solution especially for UMN disease patients. UCHL1 (ubiquitin C-terminal hydrolase-L1) is a deubiquitinating enzyme crucial for maintaining free ubiquitin levels. Corticospinal motor neurons (CSMN, a.k.a UMNs in mice) show early, selective, and profound degeneration in Uchl1nm3419 (UCHL1-/-) mice, which lack all UCHL1 function. When UCHL1 activity is ablated only from spinal motor neurons, CSMN remained intact. However, restoring UCHL1 specifically in CSMN of UCHL1-/- mice via directed gene delivery was sufficient to improve CSMN integrity to the healthy control levels. In addition, when UCHL1 gene was delivered selectively to CSMN that are diseased due to misfolded SOD1 toxicity and TDP-43 pathology via AAV-mediated retrograde transduction, the disease causing misfolded SOD1 and mutant human TDP-43 were reduced in hSOD1G93A and prpTDP-43A315T models, respectively. Diseased CSMN retained their neuronal integrity and cytoarchitectural stability in two different mouse models that represent two distinct causes of neurodegeneration in ALS.
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Affiliation(s)
- Barış Genç
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Javier H Jara
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Santana S Sanchez
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Amiko K B Lagrimas
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Öge Gözütok
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Nuran Koçak
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Yongling Zhu
- Departments of Ophthalmology and Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - P Hande Özdinler
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA.
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18
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Sangari S, Peyre I, Lackmy‐Vallée A, Bayen E, Pradat P, Marchand‐Pauvert V. Transient increase in recurrent inhibition in amyotrophic lateral sclerosis as a putative protection from neurodegeneration. Acta Physiol (Oxf) 2022; 234:e13758. [PMID: 34981890 DOI: 10.1111/apha.13758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/15/2021] [Accepted: 01/01/2022] [Indexed: 11/28/2022]
Abstract
AIM Adaptive mechanisms in spinal circuits are likely involved in homeostatic responses to maintain motor output in amyotrophic lateral sclerosis. Given the role of Renshaw cells in regulating the motoneuron input/output gain, we investigated the modulation of heteronymous recurrent inhibition. METHODS Electrical stimulations were used to activate recurrent collaterals resulting in the Hoffmann reflex depression. Inhibitions from soleus motor axons to quadriceps motoneurons, and vice versa, were tested in 38 patients and matched group of 42 controls. RESULTS Compared with controls, the mean depression of quadriceps reflex was larger in patients, while that of soleus was smaller, suggesting that heteronymous recurrent inhibition was enhanced in quadriceps but reduced in soleus. The modulation of recurrent inhibition was linked to the size of maximal direct motor response and lower limb dysfunctions, suggesting a significant relationship with the integrity of the target motoneuron pool and functional abilities. No significant link was found between the integrity of motor axons activating Renshaw cells and the level of inhibition. Enhanced inhibition was particularly observed in patients within the first year after symptom onset and with slow progression of lower limb dysfunctions. Normal or reduced inhibitions were mainly observed in patients with motor weakness first in lower limbs and greater dysfunctions in lower limbs. CONCLUSION We provide the first evidence for enhanced recurrent inhibition and speculate that Renshaw cells might have transient protective role on motoneuron by counteracting hyperexcitability at early stages. Several mechanisms likely participate including cortical influence on Renshaw cell and reinnervation by slow motoneurons.
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Affiliation(s)
- Sina Sangari
- Laboratoire d’Imagerie Biomédicale Sorbonne Université INSERM CNRS Paris France
- Shirley Ryan AbilityLab Chicago Illinois USA
- Department of Physical Medicine and Rehabilitation Northwestern University Chicago Illinois USA
| | - Iseline Peyre
- Laboratoire d’Imagerie Biomédicale Sorbonne Université INSERM CNRS Paris France
| | | | - Eléonore Bayen
- Laboratoire d’Imagerie Biomédicale Sorbonne Université INSERM CNRS Paris France
- Pôle MSN, Hôpital Pitié‐Salpêtrière AP‐HP Paris France
| | - Pierre‐François Pradat
- Laboratoire d’Imagerie Biomédicale Sorbonne Université INSERM CNRS Paris France
- Pôle MSN, Hôpital Pitié‐Salpêtrière AP‐HP Paris France
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19
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Cortical Hyperexcitability in the Driver’s Seat in ALS. CLINICAL AND TRANSLATIONAL NEUROSCIENCE 2022. [DOI: 10.3390/ctn6010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal disease characterized by the degeneration of cortical and spinal motor neurons. With no effective treatment available to date, patients face progressive paralysis and eventually succumb to the disease due to respiratory failure within only a few years. Recent research has revealed the multifaceted nature of the mechanisms and cell types involved in motor neuron degeneration, thereby opening up new therapeutic avenues. Intriguingly, two key features present in both ALS patients and rodent models of the disease are cortical hyperexcitability and hyperconnectivity, the mechanisms of which are still not fully understood. We here recapitulate current findings arguing for cell autonomous and non-cell autonomous mechanisms causing cortical excitation and inhibition imbalance, which is involved in the degeneration of motor neurons in ALS. Moreover, we will highlight recent evidence that strongly indicates a cardinal role for the motor cortex as a main driver and source of the disease, thus arguing for a corticofugal trajectory of the pathology.
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20
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Pasniceanu IS, Atwal MS, Souza CDS, Ferraiuolo L, Livesey MR. Emerging Mechanisms Underpinning Neurophysiological Impairments in C9ORF72 Repeat Expansion-Mediated Amyotrophic Lateral Sclerosis/Frontotemporal Dementia. Front Cell Neurosci 2022; 15:784833. [PMID: 34975412 PMCID: PMC8715728 DOI: 10.3389/fncel.2021.784833] [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: 09/28/2021] [Accepted: 11/10/2021] [Indexed: 12/15/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are characterized by degeneration of upper and lower motor neurons and neurons of the prefrontal cortex. The emergence of the C9ORF72 hexanucleotide repeat expansion mutation as the leading genetic cause of ALS and FTD has led to a progressive understanding of the multiple cellular pathways leading to neuronal degeneration. Disturbances in neuronal function represent a major subset of these mechanisms and because such functional perturbations precede degeneration, it is likely that impaired neuronal function in ALS/FTD plays an active role in pathogenesis. This is supported by the fact that ALS/FTD patients consistently present with neurophysiological impairments prior to any apparent degeneration. In this review we summarize how the discovery of the C9ORF72 repeat expansion mutation has contributed to the current understanding of neuronal dysfunction in ALS/FTD. Here, we discuss the impact of the repeat expansion on neuronal function in relation to intrinsic excitability, synaptic, network and ion channel properties, highlighting evidence of conserved and divergent pathophysiological impacts between cortical and motor neurons and the influence of non-neuronal cells. We further highlight the emerging association between these dysfunctional properties with molecular mechanisms of the C9ORF72 mutation that appear to include roles for both, haploinsufficiency of the C9ORF72 protein and aberrantly generated dipeptide repeat protein species. Finally, we suggest that relating key pathological observations in C9ORF72 repeat expansion ALS/FTD patients to the mechanistic impact of the C9ORF72 repeat expansion on neuronal function will lead to an improved understanding of how neurophysiological dysfunction impacts upon pathogenesis.
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Affiliation(s)
- Iris-Stefania Pasniceanu
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Manpreet Singh Atwal
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Cleide Dos Santos Souza
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Laura Ferraiuolo
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Matthew R Livesey
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, United Kingdom
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21
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McLeod VM, Chiam MDF, Perera ND, Lau CL, Boon WC, Turner BJ. Mapping Motor Neuron Vulnerability in the Neuraxis of Male SOD1 G93A Mice Reveals Widespread Loss of Androgen Receptor Occurring Early in Spinal Motor Neurons. Front Endocrinol (Lausanne) 2022; 13:808479. [PMID: 35273564 PMCID: PMC8902593 DOI: 10.3389/fendo.2022.808479] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/19/2022] [Indexed: 12/11/2022] Open
Abstract
Sex steroid hormones have been implicated as disease modifiers in the neurodegenerative disorder amyotrophic lateral sclerosis (ALS). Androgens, signalling via the androgen receptor (AR), predominate in males, and have widespread actions in the periphery and the central nervous system (CNS). AR translocates to the cell nucleus when activated upon binding androgens, whereby it regulates transcription of target genes via the classical genomic signalling pathway. We previously reported that AR protein is decreased in the lumbar spinal cord tissue of symptomatic male SOD1G93A mice. Here, we further explored the changes in AR within motor neurons (MN) of the CNS, assessing their nuclear AR content and propensity to degenerate by endstage disease in male SOD1G93A mice. We observed that almost all motor neuron populations had undergone significant loss in nuclear AR in SOD1G93A mice. Interestingly, loss of nuclear AR was evident in lumbar spinal MNs as early as the pre-symptomatic age of 60 days. Several MN populations with high AR content were identified which did not degenerate in SOD1G93A mice. These included the brainstem ambiguus and vagus nuclei, and the sexually dimorphic spinal MNs: cremaster, dorsolateral nucleus (DLN) and spinal nucleus of bulbocavernosus (SNB). In conclusion, we demonstrate that AR loss directly associates with MN vulnerability and disease progression in the SOD1G93A mouse model of ALS.
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Affiliation(s)
- Victoria M. McLeod
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Mathew D. F. Chiam
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Nirma D. Perera
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Chew L. Lau
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Wah Chin Boon
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Bradley J. Turner
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
- Perron Institute for Neurological and Translational Science, Queen Elizabeth Medical Centre, Nedlands, WA, Australia
- *Correspondence: Bradley J. Turner,
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22
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Dyer MS, Woodhouse A, Blizzard CA. Cytoplasmic Human TDP-43 Mislocalization Induces Widespread Dendritic Spine Loss in Mouse Upper Motor Neurons. Brain Sci 2021; 11:brainsci11070883. [PMID: 34209287 PMCID: PMC8301870 DOI: 10.3390/brainsci11070883] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 11/16/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is defined by the destruction of upper- and lower motor neurons. Post-mortem, nearly all ALS cases are positive for cytoplasmic aggregates containing the DNA/RNA binding protein TDP-43. Recent studies indicate that this pathogenic mislocalization of TDP-43 may participate in generating hyperexcitability of the upper motor neurons, the earliest detectable change in ALS patients, yet the mechanisms driving this remain unclear. We investigated how mislocalisation of TDP-43 could initiate network dysfunction in ALS. We employed a tetracycline inducible system to express either human wildtype TDP-43 (TDP-43WT) or human TDP-43 that cannot enter the nucleus (TDP-43ΔNLS) in excitatory neurons (Camk2α promoter), crossed Thy1-YFPH mice to visualize dendritic spines, the major site of excitatory synapses. In comparison to both TDP-43WT and controls, TDP-43ΔNLS drove a robust loss in spine density in all the dendrite regions of the upper motor neurons, most affecting thin spines. This indicates that TDP-43 is involved in the generation of network dysfunction in ALS likely through impacting the formation or durability of excitatory synapses. These findings are relevant to the vast majority of ALS cases, and provides further evidence that upper motor neurons may need to be protected from TDP-43 mediated synaptic excitatory changes early in disease.
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Affiliation(s)
- Marcus S. Dyer
- Menzies Institute for Medical Research, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
| | - Adele Woodhouse
- Wicking Dementia Research and Education Centre, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
| | - Catherine A. Blizzard
- Menzies Institute for Medical Research, College Health and Medicine, University of Tasmania, Hobart, TAS 7000, Australia;
- Correspondence:
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23
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Steffens H, Mott AC, Li S, Wegner W, Švehla P, Kan VWY, Wolf F, Liebscher S, Willig KI. Stable but not rigid: Chronic in vivo STED nanoscopy reveals extensive remodeling of spines, indicating multiple drivers of plasticity. SCIENCE ADVANCES 2021; 7:7/24/eabf2806. [PMID: 34108204 PMCID: PMC8189587 DOI: 10.1126/sciadv.abf2806] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 04/22/2021] [Indexed: 06/01/2023]
Abstract
Excitatory synapses on dendritic spines of pyramidal neurons are considered a central memory locus. To foster both continuous adaption and the storage of long-term information, spines need to be plastic and stable at the same time. Here, we advanced in vivo STED nanoscopy to superresolve distinct features of spines (head size and neck length/width) in mouse neocortex for up to 1 month. While LTP-dependent changes predict highly correlated modifications of spine geometry, we find both, uncorrelated and correlated dynamics, indicating multiple independent drivers of spine remodeling. The magnitude of this remodeling suggests substantial fluctuations in synaptic strength. Despite this high degree of volatility, all spine features exhibit persistent components that are maintained over long periods of time. Furthermore, chronic nanoscopy uncovers structural alterations in the cortex of a mouse model of neurodegeneration. Thus, at the nanoscale, stable dendritic spines exhibit a delicate balance of stability and volatility.
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Affiliation(s)
- Heinz Steffens
- Optical Nanoscopy in Neuroscience, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
- Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Alexander C Mott
- Optical Nanoscopy in Neuroscience, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
- Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Siyuan Li
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
- BioMedical Center, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Waja Wegner
- Optical Nanoscopy in Neuroscience, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
- Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Pavel Švehla
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
- BioMedical Center, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Vanessa W Y Kan
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
- BioMedical Center, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Fred Wolf
- Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Max Planck Institute for Dynamics and Self-Organization; Campus Institute for Dynamics of Biological Networks, Göttingen, Germany
| | - Sabine Liebscher
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany.
- BioMedical Center, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Katrin I Willig
- Optical Nanoscopy in Neuroscience, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany.
- Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
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24
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Fogarty MJ, Losbanos LL, Craig TA, Reynolds CJ, Brown AD, Kumar R, Sieck GC. Muscle-specific deletion of the vitamin D receptor in mice is associated with diaphragm muscle weakness. J Appl Physiol (1985) 2021; 131:95-106. [PMID: 34013750 DOI: 10.1152/japplphysiol.00194.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Diseases or conditions where diaphragm muscle (DIAm) function is impaired, including chronic obstructive pulmonary disease, cachexia, asthma, and aging, are associated with an increased risk of pulmonary symptoms, longer duration of hospitalizations, and increasing requirements for mechanical ventilation. Vitamin D deficiency is associated with proximal muscle weakness that resolves following therapy with vitamin D3. Skeletal muscle expresses the vitamin D receptor (VDR), which responds to the active form of vitamin D, 1,25-dihydroxyvitamin D3 by altering gene expression in target cells. In knockout mice without skeletal muscle VDRs, there is marked atrophy of muscle fibers and a change in skeletal muscle biochemistry. We used a tamoxifen-inducible skeletal muscle Cre recombinase in Vdrfl/fl mice (Vdrfl/fl actin.iCre+) to assess the role of muscle-specific VDR signaling on DIAm-specific force, fatigability, and fiber type-dependent morphology. Vdrfl/fl actin.iCre+ mice treated with vehicle and Vdrfl/fl mice treated with tamoxifen served as controls. Seven days following the final treatment, mice were euthanized, the DIAm was removed, and isometric force and fatigue were assessed in DIAm strips using direct muscle stimulation. The proportion and cross-sectional areas of DIAm fiber types were evaluated by immunolabeling with myosin heavy chain antibodies differentiating type I, IIa and IIx, and/or IIb fibers. We show that in mice with skeletal muscle-specific VDR deletion, maximum specific force and residual force following fatigue are impaired, along with a selective atrophy of type IIx and/or IIb fibers. These results show that the VDR has a significant biological effect on DIAm function independent of systemic effects on mineral metabolism.NEW & NOTEWORTHY Vitamin D deficiency and vitamin D receptor (VDR) polymorphisms are associated with adverse pulmonary and diaphragm muscle (DIAm)-associated respiratory outcomes. We used a skeletal muscle-specific tamoxifen-inducible VDR knockout to investigate DIAm dysfunction following reduced VDR signaling. Marked DIAm weakness and atrophy of type IIx and/or IIb fibers are present in muscle-specific tamoxifen-induced VDR knockout mice compared with controls. These results show that the VDR has a significant biological effect on DIAm function independent of systemic effects on mineral metabolism.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Louis L Losbanos
- Division of Nephrology & Hypertension, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Theodore A Craig
- Division of Nephrology & Hypertension, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Carmen J Reynolds
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Alyssa D Brown
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Rajiv Kumar
- Division of Nephrology & Hypertension, Department of Medicine, Mayo Clinic, Rochester, Minnesota.,Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
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25
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Neurophysiological Mechanisms Underlying Cortical Hyper-Excitability in Amyotrophic Lateral Sclerosis: A Review. Brain Sci 2021; 11:brainsci11050549. [PMID: 33925493 PMCID: PMC8145013 DOI: 10.3390/brainsci11050549] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neuromotor disease characterized by the loss of upper and lower motor neurons (MNs), resulting in muscle paralysis and death. Early cortical hyper-excitability is a common pathological process observed clinically and in animal disease models. Although the mechanisms that underlie cortical hyper-excitability are not completely understood, the molecular and cellular mechanisms that cause enhanced neuronal intrinsic excitability and changes in excitatory and inhibitory synaptic activity are starting to emerge. Here, we review the evidence for an anterograde glutamatergic excitotoxic process, leading to cortical hyper-excitability via intrinsic cellular and synaptic mechanisms and for the role of interneurons in establishing disinhibition in clinical and experimental settings. Understanding the mechanisms that lead to these complex pathological processes will likely produce key insights towards developing novel therapeutic strategies to rescue upper MNs, thus alleviating the impact of this fatal disease.
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26
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Liguori F, Amadio S, Volonté C. Where and Why Modeling Amyotrophic Lateral Sclerosis. Int J Mol Sci 2021; 22:ijms22083977. [PMID: 33921446 PMCID: PMC8070525 DOI: 10.3390/ijms22083977] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 02/07/2023] Open
Abstract
Over the years, researchers have leveraged a host of different in vivo models in order to dissect amyotrophic lateral sclerosis (ALS), a neurodegenerative/neuroinflammatory disease that is heterogeneous in its clinical presentation and is multigenic, multifactorial and non-cell autonomous. These models include both vertebrates and invertebrates such as yeast, worms, flies, zebrafish, mice, rats, guinea pigs, dogs and, more recently, non-human primates. Despite their obvious differences and peculiarities, only the concurrent and comparative analysis of these various systems will allow the untangling of the causes and mechanisms of ALS for finally obtaining new efficacious therapeutics. However, harnessing these powerful organisms poses numerous challenges. In this context, we present here an updated and comprehensive review of how eukaryotic unicellular and multicellular organisms that reproduce a few of the main clinical features of the disease have helped in ALS research to dissect the pathological pathways of the disease insurgence and progression. We describe common features as well as discrepancies among these models, highlighting new insights and emerging roles for experimental organisms in ALS.
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Affiliation(s)
- Francesco Liguori
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
| | - Susanna Amadio
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
| | - Cinzia Volonté
- Preclinical Neuroscience, IRCCS Santa Lucia Foundation, 00143 Rome, Italy; (F.L.); (S.A.)
- Institute for Systems Analysis and Computer Science “A. Ruberti”, National Research Council (IASI—CNR), 00185 Rome, Italy
- Correspondence: ; Tel.: +39-06-50170-3084
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27
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Fogarty MJ, Rana S, Mantilla CB, Sieck GC. Quantifying mitochondrial volume density in phrenic motor neurons. J Neurosci Methods 2021; 353:109093. [PMID: 33549636 PMCID: PMC7990712 DOI: 10.1016/j.jneumeth.2021.109093] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/26/2021] [Accepted: 02/01/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND Previous assessments of mitochondrial volume density within motor neurons used electron microscopy (EM) to image mitochondria. However, adequate identification and sampling of motor neurons within a particular motor neuron pool is largely precluded using EM. Here, we present an alternative method for determining mitochondrial volume density in identified motor neurons within the phrenic motor neuron (PhMN) pool, with greatly increased sampling. NEW METHOD This novel method for assessing mitochondrial volume density in PhMNs uses a combination of intrapleural injection of Alexa 488-conjugated cholera toxin B (CTB) to retrogradely label PhMNs, followed by intrathecal application of MitoTracker Red to label mitochondria. This technique was validated by comparison to 3D EM determination of mitochondrial volume density as a "gold standard". RESULTS A mean mitochondrial volume density of ∼11 % was observed across PhMNs using the new MitoTracker Red method. This compared favourably with mitochondrial volume density (∼11 %) measurements using EM. COMPARISON WITH EXISTING METHOD The range, mean and variance of mitochondrial volume density estimates in PhMNs were not different between EM and fluorescent imaging techniques. CONCLUSIONS Fluorescent imaging may be used to estimate mitochondrial volume density in a large sample of motor neurons, with results similar to EM, although EM did distinguish finer mitochondrion morphology compared to MitoTracker fluorescence. Compared to EM methods, the assessment of a larger sample size and unambiguous identification of motor neurons belonging to a specific motor neuron pool represent major advantages over previous methods.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States; School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4067, Australia
| | - Sabhya Rana
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States
| | - Carlos B Mantilla
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States; Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, 55905, United States
| | - Gary C Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN, 55905, United States.
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28
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Nie S, Lu J, Huang Y, Li QA. Zonisamide-loaded triblock copolymer nanomicelle as a controlled drug release platform for the treatment of oxidative stress -induced spinal cord neuronal damage. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.115233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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29
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Genç B, Gautam M, Gözütok Ö, Dervishi I, Sanchez S, Goshu GM, Koçak N, Xie E, Silverman RB, Özdinler PH. Improving mitochondria and ER stability helps eliminate upper motor neuron degeneration that occurs due to mSOD1 toxicity and TDP-43 pathology. Clin Transl Med 2021; 11:e336. [PMID: 33634973 PMCID: PMC7898037 DOI: 10.1002/ctm2.336] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Upper motor neurons (UMNs) are a key component of motor neuron circuitry. Their degeneration is a hallmark for diseases, such as hereditary spastic paraplegia (HSP), primary lateral sclerosis (PLS), and amyotrophic lateral sclerosis (ALS). Currently there are no preclinical assays investigating cellular responses of UMNs to compound treatment, even for diseases of the UMNs. The basis of UMN vulnerability is not fully understood, and no compound has yet been identified to improve the health of diseased UMNs: two major roadblocks for building effective treatment strategies. METHODS Novel UMN reporter models, in which UMNs that are diseased because of misfolded superoxide dismutase protein (mSOD1) toxicity and TDP-43 pathology are labeled with eGFP expression, allow direct assessment of UMN response to compound treatment. Electron microscopy reveals very precise aspects of endoplasmic reticulum (ER) and mitochondrial damage. Administration of NU-9, a compound initially identified based on its ability to reduce mSOD1 toxicity, has profound impact on improving the health and stability of UMNs, as identified by detailed cellular and ultrastructural analyses. RESULTS Problems with mitochondria and ER are conserved in diseased UMNs among different species. NU-9 has drug-like pharmacokinetic properties. It lacks toxicity and crosses the blood brain barrier. NU-9 improves the structural integrity of mitochondria and ER, reduces levels of mSOD1, stabilizes degenerating UMN apical dendrites, improves motor behavior measured by the hanging wire test, and eliminates ongoing degeneration of UMNs that become diseased both because of mSOD1 toxicity and TDP-43 pathology, two distinct and important overarching causes of motor neuron degeneration. CONCLUSIONS Mechanism-focused and cell-based drug discovery approaches not only addressed key cellular defects responsible for UMN loss, but also identified NU-9, the first compound to improve the health of diseased UMNs, neurons that degenerate in ALS, HSP, PLS, and ALS/FTLD patients.
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Affiliation(s)
- Barış Genç
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Mukesh Gautam
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Öge Gözütok
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Ina Dervishi
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Santana Sanchez
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Gashaw M. Goshu
- Department of ChemistryNorthwestern UniversityEvanstonIllinoisUSA
| | - Nuran Koçak
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Edward Xie
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - Richard B. Silverman
- Department of ChemistryNorthwestern UniversityEvanstonIllinoisUSA
- Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental TherapeuticsNorthwestern UniversityEvanstonIllinoisUSA
- Department of Pharmacology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
- Chemistry of Life Processes InstituteNorthwestern UniversityEvanstonIL60208
| | - P. Hande Özdinler
- Department of Neurology, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
- Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental TherapeuticsNorthwestern UniversityEvanstonIllinoisUSA
- Chemistry of Life Processes InstituteNorthwestern UniversityEvanstonIL60208
- Mesulam Center for Cognitive Neurology and Alzheimer's DiseaseNorthwestern University, Feinberg School of MedicineChicagoIL60611
- Les Turner ALS CenterNorthwestern University, Feinberg School of MedicineChicagoIL60611
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30
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Fogarty MJ, Mu EWH, Lavidis NA, Noakes PG, Bellingham MC. Size‐dependent dendritic maladaptations of hypoglossal motor neurons in SOD1
G93A
mice. Anat Rec (Hoboken) 2020; 304:1562-1581. [DOI: 10.1002/ar.24542] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 09/14/2020] [Accepted: 09/22/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Matthew J. Fogarty
- School of Biomedical Sciences The University of Queensland St Lucia Australia
- Department of Physiology and Biomedical Engineering, Mayo Clinic Rochester Minnesota USA
| | - Erica W. H. Mu
- School of Biomedical Sciences The University of Queensland St Lucia Australia
| | - Nickolas A. Lavidis
- School of Biomedical Sciences The University of Queensland St Lucia Australia
| | - Peter G. Noakes
- School of Biomedical Sciences The University of Queensland St Lucia Australia
- Queensland Brain Institute The University of Queensland St Lucia Australia
| | - Mark C. Bellingham
- School of Biomedical Sciences The University of Queensland St Lucia Australia
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31
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Chung CG, Park SS, Park JH, Lee SB. Dysregulated Plasma Membrane Turnover Underlying Dendritic Pathology in Neurodegenerative Diseases. Front Cell Neurosci 2020; 14:556461. [PMID: 33192307 PMCID: PMC7580253 DOI: 10.3389/fncel.2020.556461] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/03/2020] [Indexed: 12/29/2022] Open
Abstract
Due to their enormous surface area compared to other cell types, neurons face unique challenges in properly handling supply and retrieval of the plasma membrane (PM)-a process termed PM turnover-in their distal areas. Because of the length and extensiveness of dendritic branches in neurons, the transport of materials needed for PM turnover from soma to distal dendrites will be inefficient and quite burdensome for somatic organelles. To meet local demands, PM turnover in dendrites most likely requires local cellular machinery, such as dendritic endocytic and secretory systems, dysregulation of which may result in dendritic pathology observed in various neurodegenerative diseases (NDs). Supporting this notion, a growing body of literature provides evidence to suggest the pathogenic contribution of dysregulated PM turnover to dendritic pathology in certain NDs. In this article, we present our perspective view that impaired dendritic endocytic and secretory systems may contribute to dendritic pathology by encumbering PM turnover in NDs.
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Affiliation(s)
- Chang Geon Chung
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Sung Soon Park
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Jeong Hyang Park
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Sung Bae Lee
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
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32
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Gunes ZI, Kan VWY, Ye X, Liebscher S. Exciting Complexity: The Role of Motor Circuit Elements in ALS Pathophysiology. Front Neurosci 2020; 14:573. [PMID: 32625051 PMCID: PMC7311855 DOI: 10.3389/fnins.2020.00573] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/11/2020] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal disease, characterized by the degeneration of both upper and lower motor neurons. Despite decades of research, we still to date lack a cure or disease modifying treatment, emphasizing the need for a much-improved insight into disease mechanisms and cell type vulnerability. Altered neuronal excitability is a common phenomenon reported in ALS patients, as well as in animal models of the disease, but the cellular and circuit processes involved, as well as the causal relevance of those observations to molecular alterations and final cell death, remain poorly understood. Here, we review evidence from clinical studies, cell type-specific electrophysiology, genetic manipulations and molecular characterizations in animal models and culture experiments, which argue for a causal involvement of complex alterations of structure, function and connectivity of different neuronal subtypes within the cortical and spinal cord motor circuitries. We also summarize the current knowledge regarding the detrimental role of astrocytes and reassess the frequently proposed hypothesis of glutamate-mediated excitotoxicity with respect to changes in neuronal excitability. Together, these findings suggest multifaceted cell type-, brain area- and disease stage- specific disturbances of the excitation/inhibition balance as a cardinal aspect of ALS pathophysiology.
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Affiliation(s)
- Zeynep I Gunes
- Institute of Clinical Neuroimmunology, Klinikum der Universität München, Ludwig Maximilians University Munich, Munich, Germany.,Graduate School of Systemic Neurosciences, Ludwig Maximilians University Munich, Munich, Germany.,Biomedical Center, Ludwig Maximilians University Munich, Munich, Germany
| | - Vanessa W Y Kan
- Institute of Clinical Neuroimmunology, Klinikum der Universität München, Ludwig Maximilians University Munich, Munich, Germany.,Graduate School of Systemic Neurosciences, Ludwig Maximilians University Munich, Munich, Germany.,Biomedical Center, Ludwig Maximilians University Munich, Munich, Germany
| | - XiaoQian Ye
- Institute of Clinical Neuroimmunology, Klinikum der Universität München, Ludwig Maximilians University Munich, Munich, Germany.,Biomedical Center, Ludwig Maximilians University Munich, Munich, Germany
| | - Sabine Liebscher
- Institute of Clinical Neuroimmunology, Klinikum der Universität München, Ludwig Maximilians University Munich, Munich, Germany.,Biomedical Center, Ludwig Maximilians University Munich, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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33
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Metoprolol prevents neuronal dendrite remodeling in a canine model of chronic obstructive sleep apnea. Acta Pharmacol Sin 2020; 41:620-628. [PMID: 31863057 PMCID: PMC7470867 DOI: 10.1038/s41401-019-0323-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/26/2019] [Indexed: 12/30/2022] Open
Abstract
Obstructive sleep apnea (OSA) is closely associated with central nervous system diseases and could lead to autonomic nerve dysfunction, which is often seen in neurodegenerative diseases. Previous studies have shown that metoprolol prevents several chronic OSA-induced cardiovascular diseases through inhibiting autonomic nerve hyperactivity. It remains unclear whether chronic OSA can lead to dendritic remodeling in the brain, and whether metoprolol affects the dendritic remodeling. In this study we investigated the effect of metoprolol on dendrite morphology in a canine model of chronic OSA, which was established in beagles through clamping and reopening the endotracheal tube for 4 h every other day for 12 weeks. OSA beagles were administered metoprolol (5 mg· kg−1· d−1). The dendritic number, length, crossings and spine density of neurons in hippocampi and prefrontal cortices were assessed by Golgi staining. And the protein levels of hypoxia-inducible factor-1α (HIF-1α) and brain-derived neurotrophic factor (BDNF) were measured by Western blotting. We showed that chronic OSA successfully induced significant brain hypoxia evidenced by increased HIF-1α levels in CA1 region and dentate gyrus of hippocampi, as well as in prefrontal cortex. Furthermore, OSA led to markedly decreased dendrite number, length and intersections, spine loss as well as reduced BDNF levels. Administration of metoprolol effectively prevented the dendritic remodeling and spine loss induced by chronic OSA. In addition, administration of metoprolol reversed the decreased BDNF, which might be associated with the metoprolol-induced neuronal protection. In conclusion, metoprolol protects against neuronal dendritic remodeling in hippocampi and prefrontal cortices induced by chronic OSA in canine.
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Armada-Moreira A, Gomes JI, Pina CC, Savchak OK, Gonçalves-Ribeiro J, Rei N, Pinto S, Morais TP, Martins RS, Ribeiro FF, Sebastião AM, Crunelli V, Vaz SH. Going the Extra (Synaptic) Mile: Excitotoxicity as the Road Toward Neurodegenerative Diseases. Front Cell Neurosci 2020; 14:90. [PMID: 32390802 PMCID: PMC7194075 DOI: 10.3389/fncel.2020.00090] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 03/26/2020] [Indexed: 12/13/2022] Open
Abstract
Excitotoxicity is a phenomenon that describes the toxic actions of excitatory neurotransmitters, primarily glutamate, where the exacerbated or prolonged activation of glutamate receptors starts a cascade of neurotoxicity that ultimately leads to the loss of neuronal function and cell death. In this process, the shift between normal physiological function and excitotoxicity is largely controlled by astrocytes since they can control the levels of glutamate on the synaptic cleft. This control is achieved through glutamate clearance from the synaptic cleft and its underlying recycling through the glutamate-glutamine cycle. The molecular mechanism that triggers excitotoxicity involves alterations in glutamate and calcium metabolism, dysfunction of glutamate transporters, and malfunction of glutamate receptors, particularly N-methyl-D-aspartic acid receptors (NMDAR). On the other hand, excitotoxicity can be regarded as a consequence of other cellular phenomena, such as mitochondrial dysfunction, physical neuronal damage, and oxidative stress. Regardless, it is known that the excessive activation of NMDAR results in the sustained influx of calcium into neurons and leads to several deleterious consequences, including mitochondrial dysfunction, reactive oxygen species (ROS) overproduction, impairment of calcium buffering, the release of pro-apoptotic factors, among others, that inevitably contribute to neuronal loss. A large body of evidence implicates NMDAR-mediated excitotoxicity as a central mechanism in the pathogenesis of many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), and epilepsy. In this review article, we explore different causes and consequences of excitotoxicity, discuss the involvement of NMDAR-mediated excitotoxicity and its downstream effects on several neurodegenerative disorders, and identify possible strategies to study new aspects of these diseases that may lead to the discovery of new therapeutic approaches. With the understanding that excitotoxicity is a common denominator in neurodegenerative diseases and other disorders, a new perspective on therapy can be considered, where the targets are not specific symptoms, but the underlying cellular phenomena of the disease.
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Affiliation(s)
- Adam Armada-Moreira
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark
| | - Joana I. Gomes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Carolina Campos Pina
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Oksana K. Savchak
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Joana Gonçalves-Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Nádia Rei
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Sara Pinto
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Tatiana P. Morais
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, United Kingdom
| | - Robertta Silva Martins
- Laboratório de Neurofarmacologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
| | - Filipa F. Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Ana M. Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Vincenzo Crunelli
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, United Kingdom
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Sandra H. Vaz
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
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Patwa S, Benson CA, Dyer L, Olson K, Bangalore L, Hill M, Waxman SG, Tan AM. Spinal cord motor neuron plasticity accompanies second-degree burn injury and chronic pain. Physiol Rep 2019; 7:e14288. [PMID: 31858746 PMCID: PMC6923170 DOI: 10.14814/phy2.14288] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Burn injuries and associated complications present a major public health challenge. Many burn patients develop clinically intractable complications, including pain and other sensory disorders. Recent evidence has shown that dendritic spine neuropathology in spinal cord sensory and motor neurons accompanies central nervous system (CNS) or peripheral nervous system (PNS) trauma and disease. However, no research has investigated similar dendritic spine neuropathologies following a cutaneous thermal burn injury. In this retrospective investigation, we analyzed dendritic spine morphology and localization in alpha-motor neurons innervating a burn-injured area of the body (hind paw). To identify a molecular regulator of these dendritic spine changes, we further profiled motor neuron dendritic spines in adult mice treated with romidepsin, a clinically approved Pak1-inhibitor, or vehicle control at two postburn time points: Day 6 immediately after treatment, or Day 10 following drug withdrawal. In control treated mice, we observed an overall increase in dendritic spine density, including structurally mature spines with mushroom-shaped morphology. Pak1-inhibitor treatment reduced injury-induced changes to similar levels observed in animals without burn injury. The effectiveness of the Pak1-inhibitor was durable, since normalized dendritic spine profiles remained as long as 4 days despite drug withdrawal. This study is the first report of evidence demonstrating that a second-degree burn injury significantly affects motor neuron structure within the spinal cord. Furthermore, our results support the opportunity to study dendritic spine dysgenesis as a novel avenue to clarify the complexities of neurological disease following traumatic injury.
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Affiliation(s)
- Siraj Patwa
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Curtis A. Benson
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Lauren Dyer
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Kai‐Lan Olson
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Lakshmi Bangalore
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Myriam Hill
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Stephen G. Waxman
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
| | - Andrew M. Tan
- Department of Neurology and Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenConnecticut
- Rehabilitation Research CenterVeterans Affairs Connecticut Healthcare SystemWest HavenConnecticut
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36
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Fogarty MJ, Mu EWH, Lavidis NA, Noakes PG, Bellingham MC. Size-Dependent Vulnerability of Lumbar Motor Neuron Dendritic Degeneration in SOD1 G93A Mice. Anat Rec (Hoboken) 2019; 303:1455-1471. [PMID: 31509351 DOI: 10.1002/ar.24255] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 05/22/2019] [Accepted: 06/29/2019] [Indexed: 12/14/2022]
Abstract
The motor neuron (MN) soma surface area is correlated with motor unit type. Larger MNs innervate fast fatigue-intermediate (FInt) or fast-fatiguable (FF) muscle fibers in type FInt and FF motor units, respectively. Smaller MNs innervate slow-twitch fatigue-resistant (S) or fast fatigue-resistant (FR) muscle fibers in type S and FR motor units, respectively. In amyotrophic lateral sclerosis (ALS), FInt and FF motor units are more vulnerable, with denervation and MN death occurring for these units before the more resilient S and FR units. Abnormal MN dendritic arbors have been observed in ALS in humans and rodent models. We used a Golgi-Cox impregnation protocol to examine soma size-dependent changes in the dendritic morphology of lumbar MNs in SOD1G93A mice, a model of ALS, at pre-symptomatic, onset and mid-disease stages. In wildtype control mice, the relationship between MN soma surface area and dendritic length or dendritic spine number was highly linear (i.e., increased MN soma size correlated with increased dendritic length and spines). By contrast, in SOD1G93A mice, this linear relationship was lost and dendritic length reduction and spine loss were observed in larger MNs, from pre-symptomatic stages onward. These changes correlated with the neuromotor symptoms of ALS in rodent models. At presymptomatic ages, changes were restricted to the larger MNs, likely to comprise vulnerable FInt and FF motor units. Our results suggest morphological changes of MN dendrites and dendritic spines are likely to contribute ALS pathogenesis, not compensate for it. Anat Rec, 303:1455-1471, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
- Matthew J Fogarty
- School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Erica W H Mu
- School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Nickolas A Lavidis
- School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Peter G Noakes
- School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia.,Queensland Brain Institute, The University of Queensland, St Lucia, Queensland, Australia
| | - Mark C Bellingham
- School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia
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37
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Khurram OU, Fogarty MJ, Sarrafian TL, Bhatt A, Mantilla CB, Sieck GC. Impact of aging on diaphragm muscle function in male and female Fischer 344 rats. Physiol Rep 2019; 6:e13786. [PMID: 29981218 PMCID: PMC6035336 DOI: 10.14814/phy2.13786] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 06/08/2018] [Accepted: 06/12/2018] [Indexed: 11/24/2022] Open
Abstract
The diaphragm muscle (DIAm) is the primary inspiratory muscle in mammals and is active during ventilatory behaviors, but it is also involved in higher-force behaviors such as those necessary for clearing the airway. Our laboratory has previously reported DIAm sarcopenia in rats and mice characterized by DIAm atrophy and a reduction in maximum specific force at 24 months of age. In Fischer 344 rats, these studies were limited to male animals, although in other studies, we noted a more rapid increase in body mass from 6 to 24 months of age in females (~140%) compared to males (~110%). This difference in body weight gain suggests a possible sex difference in the manifestation of sarcopenia. In mice, we previously measured transdiaphragmatic pressure (Pdi) to evaluate in vivo DIAm force generation across a range of motor behaviors, but found no evidence of sex-related differences. The purpose of this study in Fischer 344 rats was to evaluate if there are sex-related differences in DIAm sarcopenia, and if such differences translate to a functional impact on Pdi generation across motor behaviors and maximal Pdi (Pdimax ) elicited by bilateral phrenic nerve stimulation. In both males and females, DIAm sarcopenia was apparent in 24-month-old rats with a ~30% reduction in both maximum specific force and the cross-sectional area of type IIx and/or IIb fibers. Importantly, in both males and females, Pdi generated during ventilatory behaviors was unimpaired by sarcopenia, even during more forceful ventilatory efforts induced via airway occlusion. Although ventilatory behaviors were preserved with aging, there was a ~20% reduction in Pdimax , which likely impairs the ability of the DIAm to generate higher-force expulsive airway clearance behaviors necessary to maintain airway patency.
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Affiliation(s)
- Obaid U Khurram
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Matthew J Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota.,School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| | - Tiffany L Sarrafian
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Arjun Bhatt
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Carlos B Mantilla
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota.,Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota.,Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota
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38
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Pradhan J, Noakes PG, Bellingham MC. The Role of Altered BDNF/TrkB Signaling in Amyotrophic Lateral Sclerosis. Front Cell Neurosci 2019; 13:368. [PMID: 31456666 PMCID: PMC6700252 DOI: 10.3389/fncel.2019.00368] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/29/2019] [Indexed: 12/11/2022] Open
Abstract
Brain derived neurotrophic factor (BDNF) is well recognized for its neuroprotective functions, via activation of its high affinity receptor, tropomysin related kinase B (TrkB). In addition, BDNF/TrkB neuroprotective functions can also be elicited indirectly via activation of adenosine 2A receptors (A2aRs), which in turn transactivates TrkB. Evidence suggests that alterations in BDNF/TrkB, including TrkB transactivation by A2aRs, can occur in several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Although enhancing BDNF has been a major goal for protection of dying motor neurons (MNs), this has not been successful. Indeed, there is emerging in vitro and in vivo evidence suggesting that an upregulation of BDNF/TrkB can cause detrimental effects on MNs, making them more vulnerable to pathophysiological insults. For example, in ALS, early synaptic hyper-excitability of MNs is thought to enhance BDNF-mediated signaling, thereby causing glutamate excitotoxicity, and ultimately MN death. Moreover, direct inhibition of TrkB and A2aRs has been shown to protect MNs from these pathophysiological insults, suggesting that modulation of BDNF/TrkB and/or A2aRs receptors may be important in early disease pathogenesis in ALS. This review highlights the relevance of pathophysiological actions of BDNF/TrkB under certain circumstances, so that manipulation of BDNF/TrkB and A2aRs may give rise to alternate neuroprotective therapeutic strategies in the treatment of neural diseases such as ALS.
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Affiliation(s)
- Jonu Pradhan
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Peter G Noakes
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia.,Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Mark C Bellingham
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
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39
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Histamine Is an Inducer of the Heat Shock Response in SOD1-G93A Models of ALS. Int J Mol Sci 2019; 20:ijms20153793. [PMID: 31382568 PMCID: PMC6696457 DOI: 10.3390/ijms20153793] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 12/13/2022] Open
Abstract
(1) Background: Amyotrophic lateral sclerosis (ALS) is a multifactorial non-cell autonomous disease where activation of microglia and astrocytes largely contributes to motor neurons death. Heat shock proteins have been demonstrated to promote neuronal survival and exert a strong anti-inflammatory action in glia. Having previously shown that the pharmacological increase of the histamine content in the central nervous system (CNS) of SOD1-G93A mice decreases neuroinflammation, reduces motor neuron death, and increases mice life span, here we examined whether this effect could be mediated by an enhancement of the heat shock response. (2) Methods: Heat shock protein expression was analyzed in vitro and in vivo. Histamine was provided to primary microglia and NSC-34 motor neurons expressing the SOD1-G93A mutation. The brain permeable histamine precursor histidine was chronically administered to symptomatic SOD1-G93A mice. Spine density was measured by Golgi-staining in motor cortex of histidine-treated SOD1-G93A mice. (3) Results: We demonstrate that histamine activates the heat shock response in cultured SOD1-G93A microglia and motor neurons. In SOD1-G93A mice, histidine augments the protein content of GRP78 and Hsp70 in spinal cord and cortex, where the treatment also rescues type I motor neuron dendritic spine loss. (4) Conclusion: Besides the established histaminergic neuroprotective and anti-inflammatory effects, the induction of the heat shock response in the SOD1-G93A model by histamine confirms the importance of this pathway in the search for successful therapeutic solutions to treat ALS.
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40
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Fogarty MJ, Gonzalez Porras MA, Mantilla CB, Sieck GC. Diaphragm neuromuscular transmission failure in aged rats. J Neurophysiol 2019; 122:93-104. [PMID: 31042426 PMCID: PMC6689786 DOI: 10.1152/jn.00061.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/26/2019] [Accepted: 04/26/2019] [Indexed: 12/16/2022] Open
Abstract
In aging Fischer 344 rats, phrenic motor neuron loss, neuromuscular junction abnormalities, and diaphragm muscle (DIAm) sarcopenia are present by 24 mo of age, with larger fast-twitch fatigue-intermediate (type FInt) and fast-twitch fatigable (type FF) motor units particularly vulnerable. We hypothesize that in old rats, DIAm neuromuscular transmission deficits are specific to type FInt and/or FF units. In phrenic nerve/DIAm preparations from rats at 6 and 24 mo of age, the phrenic nerve was supramaximally stimulated at 10, 40, or 75 Hz. Every 15 s, the DIAm was directly stimulated, and the difference in forces evoked by nerve and muscle stimulation was used to estimate neuromuscular transmission failure. Neuromuscular transmission failure in the DIAm was observed at each stimulation frequency. In the initial stimulus trains, the forces evoked by phrenic nerve stimulation at 40 and 75 Hz were significantly less than those evoked by direct muscle stimulation, and this difference was markedly greater in 24-mo-old rats. During repetitive nerve stimulation, neuromuscular transmission failure at 40 and 75 Hz worsened to a greater extent in 24-mo-old rats compared with younger animals. Because type IIx and/or IIb DIAm fibers (type FInt and/or FF motor units) display greater susceptibility to neuromuscular transmission failure at higher frequencies of stimulation, these data suggest that the age-related loss of larger phrenic motor neurons impacts nerve conduction to muscle at higher frequencies and may contribute to DIAm sarcopenia in old rats. NEW & NOTEWORTHY Diaphragm muscle (DIAm) sarcopenia, phrenic motor neuron loss, and perturbations of neuromuscular junctions (NMJs) are well described in aged rodents and selectively affect FInt and FF motor units. Less attention has been paid to the motor unit-specific aspects of nerve-muscle conduction. In old rats, increased neuromuscular transmission failure occurred at stimulation frequencies where FInt and FF motor units exhibit conduction failures, along with decreased apposition of pre- and postsynaptic domains of DIAm NMJs of these units.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
| | | | - Carlos B Mantilla
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic , Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic , Rochester, Minnesota
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41
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Broad RJ, Gabel MC, Dowell NG, Schwartzman DJ, Seth AK, Zhang H, Alexander DC, Cercignani M, Leigh PN. Neurite orientation and dispersion density imaging (NODDI) detects cortical and corticospinal tract degeneration in ALS. J Neurol Neurosurg Psychiatry 2019; 90:404-411. [PMID: 30361295 PMCID: PMC6581155 DOI: 10.1136/jnnp-2018-318830] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/30/2018] [Accepted: 09/25/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Corticospinal tract (CST) degeneration and cortical atrophy are consistent features of amyotrophic lateral sclerosis (ALS). We hypothesised that neurite orientation dispersion and density imaging (NODDI), a multicompartment model of diffusion MRI, would reveal microstructural changes associated with ALS within the CST and precentral gyrus (PCG) 'in vivo'. METHODS 23 participants with sporadic ALS and 23 healthy controls underwent diffusion MRI. Neurite density index (NDI), orientation dispersion index (ODI) and free water fraction (isotropic compartment (ISO)) were derived. Whole brain voxel-wise analysis was performed to assess for group differences. Standard diffusion tensor imaging (DTI) parameters were computed for comparison. Subgroup analysis was performed to investigate for NODDI parameter differences relating to bulbar involvement. Correlation of NODDI parameters with clinical variables were also explored. The results were accepted as significant where p<0.05 after family-wise error correction at the cluster level, clusters formed with p<0.001. RESULTS In the ALS group NDI was reduced in the extensive regions of the CST, the corpus callosum and the right PCG. ODI was reduced in the right anterior internal capsule and the right PCG. Significant differences in NDI were detected between subgroups stratified according to the presence or absence of bulbar involvement. ODI and ISO correlated with disease duration. CONCLUSIONS NODDI demonstrates that axonal loss within the CST is a core feature of degeneration in ALS. This is the main factor contributing to the altered diffusivity profile detected using DTI. NODDI also identified dendritic alterations within the PCG, suggesting microstructural cortical dendritic changes occur together with CST axonal damage.
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Affiliation(s)
- Rebecca J Broad
- Department of Neuroscience, Trafford Centre for Biomedical Research, Brighton and Sussex Medical School, Brighton, UK .,Brighton and Sussex University Hospitals NHS Trust, Princess Royal Hospital, Haywards Heath, UK
| | - Matt C Gabel
- Department of Neuroscience, Trafford Centre for Biomedical Research, Brighton and Sussex Medical School, Brighton, UK
| | - Nicholas G Dowell
- Department of Neuroscience, Trafford Centre for Biomedical Research, Brighton and Sussex Medical School, Brighton, UK
| | | | - Anil K Seth
- Sackler Centre Consciousness Science, University of Sussex, Brighton, UK
| | - Hui Zhang
- Centre for Medical Image Computing and Department of Computer Science, University College London, London, UK
| | - Daniel C Alexander
- Centre for Medical Image Computing and Department of Computer Science, University College London, London, UK
| | - Mara Cercignani
- Department of Neuroscience, Trafford Centre for Biomedical Research, Brighton and Sussex Medical School, Brighton, UK.,Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - P Nigel Leigh
- Department of Neuroscience, Trafford Centre for Biomedical Research, Brighton and Sussex Medical School, Brighton, UK.,Brighton and Sussex University Hospitals NHS Trust, Princess Royal Hospital, Haywards Heath, UK
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Fogarty MJ, Sieck GC. Evolution and Functional Differentiation of the Diaphragm Muscle of Mammals. Compr Physiol 2019; 9:715-766. [PMID: 30873594 PMCID: PMC7082849 DOI: 10.1002/cphy.c180012] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Symmorphosis is a concept of economy of biological design, whereby structural properties are matched to functional demands. According to symmorphosis, biological structures are never over designed to exceed functional demands. Based on this concept, the evolution of the diaphragm muscle (DIAm) in mammals is a tale of two structures, a membrane that separates and partitions the primitive coelomic cavity into separate abdominal and thoracic cavities and a muscle that serves as a pump to generate intra-abdominal (Pab ) and intrathoracic (Pth ) pressures. The DIAm partition evolved in reptiles from folds of the pleural and peritoneal membranes that was driven by the biological advantage of separating organs in the larger coelomic cavity into separate thoracic and abdominal cavities, especially with the evolution of aspiration breathing. The DIAm pump evolved from the advantage afforded by more effective generation of both a negative Pth for ventilation of the lungs and a positive Pab for venous return of blood to the heart and expulsive behaviors such as airway clearance, defecation, micturition, and child birth. © 2019 American Physiological Society. Compr Physiol 9:715-766, 2019.
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Affiliation(s)
- Matthew J Fogarty
- Mayo Clinic, Department of Physiology & Biomedical Engineering, Rochester, Minnesota, USA
| | - Gary C Sieck
- Mayo Clinic, Department of Physiology & Biomedical Engineering, Rochester, Minnesota, USA
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43
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Henstridge CM, Tzioras M, Paolicelli RC. Glial Contribution to Excitatory and Inhibitory Synapse Loss in Neurodegeneration. Front Cell Neurosci 2019; 13:63. [PMID: 30863284 PMCID: PMC6399113 DOI: 10.3389/fncel.2019.00063] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/08/2019] [Indexed: 12/12/2022] Open
Abstract
Synapse loss is an early feature shared by many neurodegenerative diseases, and it represents the major correlate of cognitive impairment. Recent studies reveal that microglia and astrocytes play a major role in synapse elimination, contributing to network dysfunction associated with neurodegeneration. Excitatory and inhibitory activity can be affected by glia-mediated synapse loss, resulting in imbalanced synaptic transmission and subsequent synaptic dysfunction. Here, we review the recent literature on the contribution of glia to excitatory/inhibitory imbalance, in the context of the most common neurodegenerative disorders. A better understanding of the mechanisms underlying pathological synapse loss will be instrumental to design targeted therapeutic interventions, taking in account the emerging roles of microglia and astrocytes in synapse remodeling.
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Affiliation(s)
- Christopher M Henstridge
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom.,Dementia Research Institute UK, The University of Edinburgh, Edinburgh, United Kingdom
| | - Makis Tzioras
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom.,Dementia Research Institute UK, The University of Edinburgh, Edinburgh, United Kingdom
| | - Rosa C Paolicelli
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
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Abstract
The synapse is an incredibly specialized structure that allows for the coordinated communication of information from one neuron to another. When assembled into circuits, steady streams of excitatory and inhibitory synaptic activity shape neural outputs. At the organismal level, ensembles of neural networks underlie behavior, emotion and memory. Disorder or dysfunctions of synapses, a synaptopathy, may underlie a host of developmental and degenerative neurological conditions. There is a possibility that amyotrophic lateral sclerosis may be a result of a synaptopathy within the neuromotor system. To this end, particular attention has been trained on the excitatory glutamatergic synapses and their morphological proxy, the dendritic spine. The extensive detailing of these dysfunctions in vulnerable neuronal populations, including corticospinal neurons and motor neurons, has recently been the subject of original research in rodents and humans. If amyotrophic lateral sclerosis is indeed a synaptopathy, it is entirely consistent with other proposed pathogenic mechanisms – including glutamate excitotoxicity, accumulation of misfolded proteins and mitochondrial dysfunction at distal axon terminals (cortico-motor neuron and neuromuscular). Further, although the exact mechanism of disease spread from region to region is unknown, the synaptopathy hypothesis is consistent with emerging die-forward evidence and the prion-like propagation of misfolded protein aggregates to distant neuronal populations. Here in this mini-review, we focus on the timeline of synaptic observations in both cortical and spinal neurons from different rodent models, and provide a conceptual framework for assessing the synaptopathy hypothesis in amyotrophic lateral sclerosis.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA; School of Biomedical Sciences, The University of Queensland, St. Lucia, Australia
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45
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Miller SJ, Glatzer JC, Hsieh YC, Rothstein JD. Cortical astroglia undergo transcriptomic dysregulation in the G93A SOD1 ALS mouse model. J Neurogenet 2018; 32:322-335. [PMID: 30398075 PMCID: PMC6444185 DOI: 10.1080/01677063.2018.1513508] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 08/06/2018] [Indexed: 12/13/2022]
Abstract
Astroglia are the most abundant glia cell in the central nervous system, playing essential roles in maintaining homeostasis. Key functions of astroglia include, but are not limited to, neurotransmitter recycling, ion buffering, immune modulation, neurotrophin secretion, neuronal synaptogenesis and elimination, and blood-brain barrier maintenance. In neurological diseases, it is well appreciated that astroglia play crucial roles in the disease pathogenesis. In amyotrophic lateral sclerosis (ALS), a motor neuron degenerative disease, astroglia in the spinal cord and cortex downregulate essential transporters, among other proteins, that exacerbate disease progression. Spinal cord astroglia undergo dramatic transcriptome dysregulation. However, in the cortex, it has not been well studied what effects glia, especially astroglia, have on upper motor neurons in the pathology of ALS. To begin to shed light on the involvement and dysregulation that astroglia undergo in ALS, we isolated pure grey-matter cortical astroglia and subjected them to microarray analysis. We uncovered a vast number of genes that show dysregulation at end-stage in the ALS mouse model, G93A SOD1. Many of these genes play essential roles in ion homeostasis and the Wnt-signaling pathway. Several of these dysregulated genes are common in ALS spinal cord astroglia, while many of them are unique. This database serves as an approach for understanding the significance of dysfunctional genes and pathways in cortical astroglia in the context of motor neuron disease, as well as determining regional astroglia heterogeneity, and providing insight into ALS pathogenesis.
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Affiliation(s)
- Sean J. Miller
- Dept. of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205
- Cellular and Molecular Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205
- The Brain Science Institute, Johns Hopkins University, Baltimore, MD 21205
| | - Jenna C. Glatzer
- Dept. of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205
- Cellular and Molecular Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205
- The Brain Science Institute, Johns Hopkins University, Baltimore, MD 21205
| | - Yi-chun Hsieh
- Dept. of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205
- The Brain Science Institute, Johns Hopkins University, Baltimore, MD 21205
| | - Jeffrey D. Rothstein
- Dept. of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205
- Cellular and Molecular Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205
- The Brain Science Institute, Johns Hopkins University, Baltimore, MD 21205
- Dept. of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD 21205
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46
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Reischauer C, Gutzeit A, Neuwirth C, Fuchs A, Sartoretti-Schefer S, Weber M, Czell D. In-vivo evaluation of neuronal and glial changes in amyotrophic lateral sclerosis with diffusion tensor spectroscopy. Neuroimage Clin 2018; 20:993-1000. [PMID: 30317156 PMCID: PMC6190601 DOI: 10.1016/j.nicl.2018.10.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 08/21/2018] [Accepted: 10/02/2018] [Indexed: 02/08/2023]
Abstract
Diffusion tensor spectroscopy (DTS) combines features of magnetic resonance spectroscopy and diffusion tensor imaging and permits evaluating cell-type specific properties of microstructure by probing the diffusion of intracellular metabolites. This exploratory study investigates for the first time microstructural changes in the neuronal and glial compartments of the brain of patients with amyotrophic lateral sclerosis (ALS) using DTS. To this end, the diffusion properties of the neuronal metabolite tNAA (N-acetylaspartate + N-acetylaspartylglutamate) and the predominantly glial metabolites tCr (creatine + phosphocreatine) and tCho (choline-containing compounds) were evaluated in the primary motor cortex of 24 ALS patients and 27 healthy controls. Significantly increased values in the diffusivities of all three metabolites were found in ALS patients relative to controls. Further analysis revealed more pronounced microstructural alterations in ALS patients with limb onset than with bulbar onset relative to controls. This observation may be related to the fact that the spectroscopic voxel was positioned in the part of the motor cortex where the motor functions of the limbs are represented. The higher diffusivities of tNAA may reflect neuronal damage and/or may be a consequence of mitochondrial dysfunction in ALS. Increased diffusivities of tCr and tCho are in line with reactive microglia and astrocytes surrounding degenerating motor neurons in the primary motor cortex of ALS patients. This pilot study demonstrates for the first time that cell-type specific microstructural alterations in the brain of ALS patients may be explored in vivo and non-invasively with DTS. In conjunction with other microstructural magnetic resonance imaging techniques, DTS may provide further insights into the pathogenic mechanisms that underlie neurodegeneration in ALS.
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Affiliation(s)
- Carolin Reischauer
- Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Hirslanden Hospital St. Anna, Lucerne, Switzerland; Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland.
| | - Andreas Gutzeit
- Institute of Radiology and Nuclear Medicine, Clinical Research Unit, Hirslanden Hospital St. Anna, Lucerne, Switzerland; Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland; Department of Radiology, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Christoph Neuwirth
- Neuromoscular Disease Unit, ALS Clinic, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Alexander Fuchs
- Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland
| | | | - Markus Weber
- Neuromoscular Disease Unit, ALS Clinic, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - David Czell
- Department of Neurology, Cantonal Hospital Winterthur, Winterthur, Switzerland; Department of Neurology, Spital Linth, Uznach, Switzerland
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Clark RM, Brizuela M, Blizzard CA, Dickson TC. Reduced Excitability and Increased Neurite Complexity of Cortical Interneurons in a Familial Mouse Model of Amyotrophic Lateral Sclerosis. Front Cell Neurosci 2018; 12:328. [PMID: 30323744 PMCID: PMC6172321 DOI: 10.3389/fncel.2018.00328] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022] Open
Abstract
Cortical interneurons play a crucial role in regulating inhibitory-excitatory balance in brain circuits, filtering synaptic information and dictating the activity of pyramidal cells through the release of GABA. In the fatal motor neuron (MN) disease, amyotrophic lateral sclerosis (ALS), an imbalance between excitation and inhibition is an early event in the motor cortex, preceding the development of overt clinical symptoms. Patients with both sporadic and familial forms of the disease exhibit reduced cortical inhibition, including patients with mutations in the copper/zinc superoxide-dismutase-1 (SOD1) gene. In this study, we investigated the influence of the familial disease-causing hSOD1-G93A ALS mutation on cortical interneurons in neuronal networks. We performed whole-cell patch-clamp recordings and neurobiotin tracing from GFP positive interneurons in primary cortical cultures derived from Gad67-GFP::hSOD1G93A mouse embryos. Targeted recordings revealed no overt differences in the passive properties of Gad67-GFP::hSOD1G93A interneurons, however the peak outward current was significantly diminished and cells were less excitable compared to Gad67-GFP::WT controls. Post hoc neurite reconstruction identified a significantly increased morphological complexity of the Gad67-GFP::hSOD1G93A interneuron neurite arbor compared to Gad67-GFP::WT controls. Our results from the SOD1 model suggest that cortical interneurons have electrophysiological and morphological alterations that could contribute to attenuated inhibitory function in the disease. Determining if these phenomena are driven by the network or represent intrinsic alteration of the interneuron may help explain the emergence of inhibitory susceptibility and ultimately disrupted excitability, in ALS.
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Affiliation(s)
- Rosemary M Clark
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Mariana Brizuela
- Flinders Medical Centre, Flinders University, Adelaide, SA, Australia
| | - Catherine A Blizzard
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Tracey C Dickson
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
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Commisso B, Ding L, Varadi K, Gorges M, Bayer D, Boeckers TM, Ludolph AC, Kassubek J, Müller OJ, Roselli F. Stage-dependent remodeling of projections to motor cortex in ALS mouse model revealed by a new variant retrograde-AAV9. eLife 2018; 7:36892. [PMID: 30136928 PMCID: PMC6125125 DOI: 10.7554/elife.36892] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 08/21/2018] [Indexed: 01/18/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of motoneurons in the primary motor cortex (pMO) and in spinal cord. However, the pathogenic process involves multiple subnetworks in the brain and functional MRI studies demonstrate an increase in functional connectivity in areas connected to pMO despite the ongoing neurodegeneration. The extent and the structural basis of the motor subnetwork remodeling in experimentally tractable models remain unclear. We have developed a new retrograde AAV9 to quantitatively map the projections to pMO in the SOD1(G93A) ALS mouse model. We show an increase in the number of neurons projecting from somatosensory cortex to pMO at presymptomatic stages, followed by an increase in projections from thalamus, auditory cortex and contralateral MO (inputs from 20 other structures remains unchanged) as disease advances. The stage- and structure-dependent remodeling of projection to pMO in ALS may provide insights into the hyperconnectivity observed in ALS patients.
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Affiliation(s)
| | - Lingjun Ding
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Karl Varadi
- Department of Internal Medicine III, University Hospital Heidelberg, Heidelberg, Germany
| | - Martin Gorges
- Department of Neurology, University of Ulm, Ulm, Germany
| | - David Bayer
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Tobias M Boeckers
- Department of Anatomy and Cell biology, University of Ulm, Ulm, Germany
| | | | - Jan Kassubek
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Oliver J Müller
- Department of Internal Medicine, University of Kiel, Kiel, Germany
| | - Francesco Roselli
- Department of Neurology, University of Ulm, Ulm, Germany.,Department of Anatomy and Cell biology, University of Ulm, Ulm, Germany
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49
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Driven to decay: Excitability and synaptic abnormalities in amyotrophic lateral sclerosis. Brain Res Bull 2018; 140:318-333. [PMID: 29870780 DOI: 10.1016/j.brainresbull.2018.05.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/26/2018] [Accepted: 05/31/2018] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is the most common motor neuron (MN) disease and is clinically characterised by the death of corticospinal motor neurons (CSMNs), spinal and brainstem MNs and the degeneration of the corticospinal tract. Degeneration of CSMNs and MNs leads inexorably to muscle wastage and weakness, progressing to eventual death within 3-5 years of diagnosis. The CSMNs, located within layer V of the primary motor cortex, project axons constituting the corticospinal tract, forming synaptic connections with brainstem and spinal cord interneurons and MNs. Clinical ALS may be divided into familial (∼10% of cases) or sporadic (∼90% of cases), based on apparent random incidence. The emergence of transgenic murine models, expressing different ALS-associated mutations has accelerated our understanding of ALS pathogenesis, although precise mechanisms remain elusive. Multiple avenues of investigation suggest that cortical electrical abnormalities have pre-eminence in the pathophysiology of ALS. In addition, glutamate-mediated functional and structural alterations in both CSMNs and MNs are present in both sporadic and familial forms of ALS. This review aims to promulgate debate in the field with regard to the common aetiology of sporadic and familial ALS. A specific focus on a nexus point in ALS pathogenesis, namely, the synaptic and intrinsic hyperexcitability of CSMNs and MNs and alterations to their structure are comprehensively detailed. The association of extramotor dysfunction with neuronal structural/functional alterations will be discussed. Finally, the implications of the latest research on the dying-forward and dying-back controversy are considered.
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50
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Specialized Subpopulations of Deep-Layer Pyramidal Neurons in the Neocortex: Bridging Cellular Properties to Functional Consequences. J Neurosci 2018; 38:5441-5455. [PMID: 29798890 DOI: 10.1523/jneurosci.0150-18.2018] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/09/2018] [Accepted: 05/11/2018] [Indexed: 12/25/2022] Open
Abstract
Neocortical pyramidal neurons with somata in layers 5 and 6 are among the most visually striking and enigmatic neurons in the brain. These deep-layer pyramidal neurons (DLPNs) integrate a plethora of cortical and extracortical synaptic inputs along their impressive dendritic arbors. The pattern of cortical output to both local and long-distance targets is sculpted by the unique physiological properties of specific DLPN subpopulations. Here we revisit two broad DLPN subpopulations: those that send their axons within the telencephalon (intratelencephalic neurons) and those that project to additional target areas outside the telencephalon (extratelencephalic neurons). While neuroscientists across many subdisciplines have characterized the intrinsic and synaptic physiological properties of DLPN subpopulations, our increasing ability to selectively target and manipulate these output neuron subtypes advances our understanding of their distinct functional contributions. This Viewpoints article summarizes our current knowledge about DLPNs and highlights recent work elucidating the functional differences between DLPN subpopulations.
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