1
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Brady ST, Mesnard-Hoaglin NA, Mays S, Priego M, Dziechciowska J, Morris S, Kang M, Tsai MY, Purks JL, Klein A, Gaona A, Melloni A, Connors T, Hyman B, Song Y, Morfini GA. Toxic effects of mutant huntingtin in axons are mediated by its proline-rich domain. Brain 2024; 147:2098-2113. [PMID: 37633260 PMCID: PMC11146425 DOI: 10.1093/brain/awad280] [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: 01/09/2023] [Revised: 05/13/2023] [Accepted: 07/17/2023] [Indexed: 08/28/2023] Open
Abstract
Huntington's disease results from expansion of a polyglutamine tract (polyQ) in mutant huntingtin (mHTT) protein, but mechanisms underlying polyQ expansion-mediated toxic gain-of-mHTT function remain elusive. Here, deletion and antibody-based experiments revealed that a proline-rich domain (PRD) adjacent to the polyQ tract is necessary for mHTT to inhibit fast axonal transport and promote axonal pathology in cultured mammalian neurons. Further, polypeptides corresponding to subregions of the PRD sufficed to elicit the toxic effect on fast axonal transport, which was mediated by c-Jun N-terminal kinases (JNKs) and involved PRD binding to one or more SH3-domain containing proteins. Collectively, these data suggested a mechanism whereby polyQ tract expansion in mHTT promotes aberrant PRD exposure and interactions of this domain with SH3 domain-containing proteins including some involved in activation of JNKs. In support, biochemical and immunohistochemical experiments linked aberrant PRD exposure to increased JNK activation in striatal tissues of the zQ175 mouse model and from post-mortem Huntington's disease patients. Together, these findings support a critical role of PRD on mHTT toxicity, suggesting a novel framework for the potential development of therapies aimed to halt or reduce axonal pathology in Huntington's disease.
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Affiliation(s)
- Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | | | - Sarah Mays
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Mercedes Priego
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Joanna Dziechciowska
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Sarah Morris
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Minsu Kang
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Ming Ying Tsai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
| | | | - Alison Klein
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Angelica Gaona
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Alexandra Melloni
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Theresa Connors
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Bradley Hyman
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02129, USA
| | - Yuyu Song
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
- Department of Neurology, Harvard Medical School, Boston, MA 02129, USA
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL 60612, USA
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
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2
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Pérot JB, Brouillet E, Flament J. The contribution of preclinical magnetic resonance imaging and spectroscopy to Huntington's disease. Front Aging Neurosci 2024; 16:1306312. [PMID: 38414634 PMCID: PMC10896846 DOI: 10.3389/fnagi.2024.1306312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 01/24/2024] [Indexed: 02/29/2024] Open
Abstract
Huntington's disease is an inherited disorder characterized by psychiatric, cognitive, and motor symptoms due to degeneration of medium spiny neurons in the striatum. A prodromal phase precedes the onset, lasting decades. Current biomarkers include clinical score and striatal atrophy using Magnetic Resonance Imaging (MRI). These markers lack sensitivity for subtle cellular changes during the prodromal phase. MRI and MR spectroscopy offer different contrasts for assessing metabolic, microstructural, functional, or vascular alterations in the disease. They have been used in patients and mouse models. Mouse models can be of great interest to study a specific mechanism of the degenerative process, allow better understanding of the pathogenesis from the prodromal to the symptomatic phase, and to evaluate therapeutic efficacy. Mouse models can be divided into three different constructions: transgenic mice expressing exon-1 of human huntingtin (HTT), mice with an artificial chromosome expressing full-length human HTT, and knock-in mouse models with CAG expansion inserted in the murine htt gene. Several studies have used MRI/S to characterized these models. However, the multiplicity of modalities and mouse models available complicates the understanding of this rich corpus. The present review aims at giving an overview of results obtained using MRI/S for each mouse model of HD, to provide a useful resource for the conception of neuroimaging studies using mouse models of HD. Finally, despite difficulties in translating preclinical protocols to clinical applications, many biomarkers identified in preclinical models have already been evaluated in patients. This review also aims to cover this aspect to demonstrate the importance of MRI/S for studying HD.
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Affiliation(s)
- Jean-Baptiste Pérot
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Paris, France
| | - Emmanuel Brouillet
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
| | - Julien Flament
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
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3
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Berth SH, Lloyd TE. Disruption of axonal transport in neurodegeneration. J Clin Invest 2023; 133:168554. [PMID: 37259916 DOI: 10.1172/jci168554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
Neurons are markedly compartmentalized, which makes them reliant on axonal transport to maintain their health. Axonal transport is important for anterograde delivery of newly synthesized macromolecules and organelles from the cell body to the synapse and for the retrograde delivery of signaling endosomes and autophagosomes for degradation. Dysregulation of axonal transport occurs early in neurodegenerative diseases and plays a key role in axonal degeneration. Here, we provide an overview of mechanisms for regulation of axonal transport; discuss how these mechanisms are disrupted in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, hereditary spastic paraplegia, amyotrophic lateral sclerosis, and Charcot-Marie-Tooth disease; and discuss therapeutic approaches targeting axonal transport.
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4
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Pepe G, Lenzi P, Capocci L, Marracino F, Pizzati L, Scarselli P, Di Pardo A, Fornai F, Maglione V. Treatment with the Glycosphingolipid Modulator THI Rescues Myelin Integrity in the Striatum of R6/2 HD Mice. Int J Mol Sci 2023; 24:ijms24065956. [PMID: 36983032 PMCID: PMC10053002 DOI: 10.3390/ijms24065956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Huntington's disease is one of the most common dominantly inherited neurodegenerative disorders caused by an expansion of a polyglutamine (polyQ) stretch in the N-terminal region of huntingtin (Htt). Among all the molecular mechanisms, affected by the mutation, emerging evidence proposes glycosphingolipid dysfunction as one of the major determinants. High levels of sphingolipids have been found to localize in the myelin sheaths of oligodendrocytes, where they play an important role in myelination stability and functions. In this study, we investigated any potential existing link between sphingolipid modulation and myelin structure by performing both ultrastructural and biochemical analyses. Our findings demonstrated that the treatment with the glycosphingolipid modulator THI preserved myelin thickness and the overall structure and reduced both area and diameter of pathologically giant axons in the striatum of HD mice. These ultrastructural findings were associated with restoration of different myelin marker protein, such as myelin-associated glycoprotein (MAG), myelin basic protein (MBP) and 2', 3' Cyclic Nucleotide 3'-Phosphodiesterase (CNP). Interestingly, the compound modulated the expression of glycosphingolipid biosynthetic enzymes and increased levels of GM1, whose elevation has been extensively reported to be associated with reduced toxicity of mutant Htt in different HD pre-clinical models. Our study further supports the evidence that the metabolism of glycosphingolipids may represent an effective therapeutic target for the disease.
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Affiliation(s)
- Giuseppe Pepe
- IRCCS Neuromed, Via Dell'elettronica, 86077 Pozzilli, Italy
| | - Paola Lenzi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Luca Capocci
- IRCCS Neuromed, Via Dell'elettronica, 86077 Pozzilli, Italy
| | | | | | | | - Alba Di Pardo
- IRCCS Neuromed, Via Dell'elettronica, 86077 Pozzilli, Italy
| | - Francesco Fornai
- IRCCS Neuromed, Via Dell'elettronica, 86077 Pozzilli, Italy
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
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5
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A Transgenic 5xFAD-M Line of Mice for Dendritic Spine Morphology Analysis in Alzheimer's Disease. Brain Sci 2023; 13:brainsci13020307. [PMID: 36831849 PMCID: PMC9954381 DOI: 10.3390/brainsci13020307] [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: 12/23/2022] [Revised: 02/03/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
Cognitive impairments are closely related to synaptic loss in Alzheimer's disease (AD). Functional changes in synaptic contacts are reflected in dendritic spine morphology. Visualization of neurons for morphological studies in vivo is complicated by the fixed brain slice staining or expensive adeno-associated virus injections. We created a transgenic 5xFAD-M line of mice with AD-associated mutations and expressed GFP protein in single neurons of the brain. This mouse model of AD is a useful tool for the simplified visualization of the hippocampal neurons' morphology in vivo without additional staining manipulations. The progressive elimination of mushroom spines was demonstrated in 5xFAD-M mice between 4 and 5 months of age. Five-month-old 5xFAD-M male and female mice showed change both in the total density and the mushroom spines number compared to sex-matched control. We conclude 5xFAD-M mice can be a useful AD model for studying the mechanisms of synaptic pathology under neurodegenerative conditions and evaluating the effects of potential therapeutic agents on spine morphology as crucial aspect of memory loss in AD.
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6
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Sun Y, Tong H, Yang T, Liu L, Li XJ, Li S. Insights into White Matter Defect in Huntington's Disease. Cells 2022; 11:3381. [PMID: 36359783 PMCID: PMC9656068 DOI: 10.3390/cells11213381] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 08/05/2023] Open
Abstract
Huntington's disease (HD) is an autosomal-dominant inherited progressive neurodegenerative disorder. It is caused by a CAG repeat expansion in the Huntingtin gene that is translated to an expanded polyglutamine (PolyQ) repeat in huntingtin protein. HD is characterized by mood swings, involuntary movement, and cognitive decline in the late disease stage. HD patients often die 15-20 years after disease onset. Currently, there is no cure for HD. Due to the striking neuronal loss in HD, most studies focused on the investigation of the predominantly neuronal degeneration in specific brain regions. However, the pathology of the white matter area in the brains of HD patients was also reported by clinical imaging studies, which showed white matter abnormalities even before the clinical onset of HD. Since oligodendrocytes form myelin sheaths around the axons in the brain, white matter lesions are likely attributed to alterations in myelin and oligodendrocyte-associated changes in HD. In this review, we summarized the evidence for white matter, myelin, and oligodendrocytes alterations that were previously observed in HD patients and animal models. We also discussed potential mechanisms for white matter changes and possible treatment to prevent glial dysfunction in HD.
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7
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Pathophysiology of neurodegenerative diseases: An interplay among axonal transport failure, oxidative stress, and inflammation? Semin Immunol 2022; 59:101628. [PMID: 35779975 PMCID: PMC9807734 DOI: 10.1016/j.smim.2022.101628] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 04/09/2022] [Accepted: 06/13/2022] [Indexed: 01/15/2023]
Abstract
Neurodegenerative diseases (NDs) are heterogeneous neurological disorders characterized by a progressive loss of selected neuronal populations. A significant risk factor for most NDs is aging. Considering the constant increase in life expectancy, NDs represent a global public health burden. Axonal transport (AT) is a central cellular process underlying the generation and maintenance of neuronal architecture and connectivity. Deficits in AT appear to be a common thread for most, if not all, NDs. Neuroinflammation has been notoriously difficult to define in relation to NDs. Inflammation is a complex multifactorial process in the CNS, which varies depending on the disease stage. Several lines of evidence suggest that AT defect, axonopathy and neuroinflammation are tightly interlaced. However, whether these impairments play a causative role in NDs or are merely a downstream effect of neuronal degeneration remains unsettled. We still lack reliable information on the temporal relationship between these pathogenic mechanisms, although several findings suggest that they may occur early during ND pathophysiology. This article will review the latest evidence emerging on whether the interplay between AT perturbations and some aspects of CNS inflammation can participate in ND etiology, analyze their potential as therapeutic targets, and the urge to identify early surrogate biomarkers.
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8
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Oh SL, Chen CM, Wu YR, Valdes Hernandez M, Tsai CC, Cheng JS, Chen YL, Wu YM, Lin YC, Wang JJ. Fixel-Based Analysis Effectively Identifies White Matter Tract Degeneration in Huntington's Disease. Front Neurosci 2021; 15:711651. [PMID: 34588947 PMCID: PMC8473742 DOI: 10.3389/fnins.2021.711651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
Microstructure damage in white matter might be linked to regional and global atrophy in Huntington's Disease (HD). We hypothesize that degeneration of subcortical regions, including the basal ganglia, is associated with damage of white matter tracts linking these affected regions. We aim to use fixel-based analysis to identify microstructural changes in the white matter tracts. To further assess the associated gray matter damage, diffusion tensor-derived indices were measured from regions of interest located in the basal ganglia. Diffusion weighted images were acquired from 12 patients with HD and 12 healthy unrelated controls using a 3 Tesla scanner. Reductions in fixel-derived metrics occurs in major white matter tracts, noticeably in corpus callosum, internal capsule, and the corticospinal tract, which were closely co-localized with the regions of increased diffusivity in basal ganglia. These changes in diffusion can be attributed to potential axonal degeneration. Fixel-based analysis is effective in studying white matter tractography and fiber changes in HD.
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Affiliation(s)
- Sher Li Oh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Chiung-Mei Chen
- Department of Neurology, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yih-Ru Wu
- Department of Neurology, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Maria Valdes Hernandez
- Row Fogo Centre for Research into Ageing and the Brain, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, United Kingdom.,Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Chih-Chien Tsai
- Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Jur-Shan Cheng
- Clinical Informatics and Medical Statistics Research Center, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Emergency Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yao-Liang Chen
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yi-Ming Wu
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Chun Lin
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Jiun-Jie Wang
- Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan.,Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Keelung, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan.,Medical Imaging Research Center, Institute for Radiological Research, Linkou Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan
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9
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Ingannato A, Bagnoli S, Mazzeo S, Bessi V, Matà S, Del Mastio M, Lombardi G, Ferrari C, Sorbi S, Nacmias B. Neurofilament Light Chain and Intermediate HTT Alleles as Combined Biomarkers in Italian ALS Patients. Front Neurosci 2021; 15:695049. [PMID: 34539331 PMCID: PMC8446383 DOI: 10.3389/fnins.2021.695049] [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: 04/14/2021] [Accepted: 08/06/2021] [Indexed: 11/29/2022] Open
Abstract
Objective To study the possible implication of the two biomarkers, intermediate alleles (IAs) of the Huntingtin (HTT) gene and neurofilament light chain (NfL) levels in plasma, in amyotrophic lateral sclerosis (ALS) patients. Methods We analyzed IAs in a cohort of 106 Italian ALS patients and measured the plasma NfL levels in 20% of the patients of the cohort. We correlated the two biomarkers with clinical phenotypes. Results Intermediate alleles were present in 7.5% of the patients of our cohort, a frequency higher than that reported in general population. Plasma NfL levels increased with age at onset (p < 0.05). Patients with bulbar onset (BO) had higher plasma NfL concentration (CI −0.61 to −0.06, p = 0.02) and a later age at onset of the disease (CI −24.78 to −4.93, p = 0.006) with respect to the spinal onset (SO) form. Additionally, two of the patients, with IAs and plasma NfL concentration lower with respect to normal alleles’ carriers, presented an age at onset higher than the mean of the entire cohort. Conclusion According to our findings, plasma NfL and IAs of HTT gene may represent potential biomarkers in ALS, providing evidence of a possible implication in clinical phenotype.
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Affiliation(s)
| | - Silvia Bagnoli
- NEUROFARBA Department, University of Florence, Florence, Italy
| | | | - Valentina Bessi
- NEUROFARBA Department, University of Florence, Florence, Italy
| | - Sabrina Matà
- SOD Neurologia 1, Dipartimento Neuromuscolo-Scheletrico e Degli Organi di Senso, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | - Monica Del Mastio
- SOD Neurologia 1, Dipartimento Neuromuscolo-Scheletrico e Degli Organi di Senso, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | | | - Camilla Ferrari
- NEUROFARBA Department, University of Florence, Florence, Italy
| | - Sandro Sorbi
- NEUROFARBA Department, University of Florence, Florence, Italy.,IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Benedetta Nacmias
- NEUROFARBA Department, University of Florence, Florence, Italy.,IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
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10
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Ferrari Bardile C, Sidik H, Quek R, Yusof NABM, Garcia-Miralles M, Pouladi MA. Abnormal Spinal Cord Myelination due to Oligodendrocyte Dysfunction in a Model of Huntington's Disease. J Huntingtons Dis 2021; 10:377-384. [PMID: 34366364 DOI: 10.3233/jhd-210495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The relative contribution of grey matter (GM) and white matter (WM) degeneration to the progressive brain atrophy in Huntington's disease (HD) has been well studied. The pathology of the spinal cord in HD is comparatively less well documented. OBJECTIVE We aim to characterize spinal cord WM abnormalities in a mouse model of HD and evaluate whether selective removal of mutant huntingtin (mHTT) from oligodendroglia rescues these deficits. METHODS Histological assessments were used to determine the area of GM and WM in the spinal cord of 12-month-old BACHD mice, while electron microscopy was used to analyze myelin fibers in the cervical area of the spinal cord. To investigate the impact of inactivation of mHTT in oligodendroglia on these measures, we used the previously described BACHDxNG2Cre mouse line where mHTT is specifically reduced in oligodendrocyte progenitor cells. RESULTS We show that spinal GM and WM areas are significantly atrophied in HD mice compared to wild-type controls. We further demonstrate that specific reduction of mHTT in oligodendroglial cells rescues the atrophy of spinal cord WM, but not GM, observed in HD mice. Inactivation of mHTT in oligodendroglia had no effect on the density of oligodendroglial cells but enhanced the expression of myelin-related proteins in the spinal cord. CONCLUSION Our findings demonstrate that the myelination abnormalities observed in brain WM structures in HD extend to the spinal cord and suggest that specific expression of mHTT in oligodendrocytes contributes to such abnormalities.
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Affiliation(s)
- Costanza Ferrari Bardile
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A *STAR), Singapore.,Departments of Medicine and Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,British Columbia Children's Hospital Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, Canada
| | - Harwin Sidik
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A *STAR), Singapore
| | - Reynard Quek
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A *STAR), Singapore
| | | | - Marta Garcia-Miralles
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A *STAR), Singapore
| | - Mahmoud A Pouladi
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A *STAR), Singapore.,Departments of Medicine and Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,British Columbia Children's Hospital Research Institute, Department of Medical Genetics, University of British Columbia, Vancouver, Canada
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11
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Gatto RG, Weissmann C, Amin M, Angeles-López QD, García-Lara L, Castellanos LCS, Deyoung D, Segovia J, Mareci TH, Uchitel OD, Magin RL. Evaluation of early microstructural changes in the R6/1 mouse model of Huntington's disease by ultra-high field diffusion MR imaging. Neurobiol Aging 2021; 102:32-49. [PMID: 33765430 DOI: 10.1016/j.neurobiolaging.2021.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 02/04/2021] [Accepted: 02/07/2021] [Indexed: 12/21/2022]
Abstract
Diffusion MRI (dMRI) has been able to detect early structural changes related to neurological symptoms present in Huntington's disease (HD). However, there is still a knowledge gap to interpret the biological significance at early neuropathological stages. The purpose of this study is two-fold: (i) establish if the combination of Ultra-High Field Diffusion MRI (UHFD-MRI) techniques can add a more comprehensive analysis of the early microstructural changes observed in HD, and (ii) evaluate if early changes in dMRI microstructural parameters can be linked to cellular biomarkers of neuroinflammation. Ultra-high field magnet (16.7T), diffusion tensor imaging (DTI), and neurite orientation dispersion and density imaging (NODDI) techniques were applied to fixed ex-vivo brains of a preclinical model of HD (R6/1 mice). Fractional anisotropy (FA) was decreased in deep and superficial grey matter (GM) as well as white matter (WM) brain regions with well-known early HD microstructure and connectivity pathology. NODDI parameters associated with the intracellular and extracellular compartment, such as intracellular ventricular fraction (ICVF), orientation dispersion index (ODI), and isotropic volume fractions (IsoVF) were altered in R6/1 mice GM. Further, histological studies in these areas showed that glia cell markers associated with neuroinflammation (GFAP & Iba1) were consistent with the dMRI findings. dMRI can be used to extract non-invasive information of neuropathological events present in the early stages of HD. The combination of multiple imaging techniques represents a better approach to understand the neuropathological process allowing the early diagnosis and neuromonitoring of patients affected by HD.
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Affiliation(s)
- Rodolfo G Gatto
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA.
| | - Carina Weissmann
- Insituto de Fisiología Biología Molecular y Neurociencias-IFIBYNE-CONICET, Universidad de Buenos, Aires, Argentina
| | - Manish Amin
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Quetzalli D Angeles-López
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, México City, México
| | - Lucia García-Lara
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, México City, México
| | - Libia C Salinas Castellanos
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, México City, México
| | - Daniel Deyoung
- Department of Biochemistry, National High Magnetic Field Laboratory, Gainesville, FL, USA
| | - Jose Segovia
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, México City, México
| | - Thomas H Mareci
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Osvaldo D Uchitel
- Insituto de Fisiología Biología Molecular y Neurociencias-IFIBYNE-CONICET, Universidad de Buenos, Aires, Argentina
| | - Richard L Magin
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
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12
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Raj A, Powell F. Network model of pathology spread recapitulates neurodegeneration and selective vulnerability in Huntington's Disease. Neuroimage 2021; 235:118008. [PMID: 33789134 DOI: 10.1016/j.neuroimage.2021.118008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/16/2021] [Accepted: 03/23/2021] [Indexed: 12/12/2022] Open
Abstract
Huntington's Disease (HD), an autosomal dominant genetic disorder caused by a mutation in the Huntingtin gene (HTT), displays a stereotyped topography in the human brain and a stereotyped progression, initially appearing in the striatum. Like other degenerative diseases, spatial topography of HD is divorced from where implicated genes are expressed, a dissociation whose mechanistic underpinning is not currently understood. Cell autonomous molecular factors characterized by gene expression signatures, including proteolytic and post translational modifications, play a role in vulnerability to disease. Non-autonomous mechanisms, likely involving the brain's anatomic or functional connectivity patterns, might also be responsible for selective vulnerability in HD. Leveraging a large dataset of 635 subjects from a multinational study, this paper tests various cell-autonomous and non-autonomous models that can explain HD topography. We test whether the expression patterns of implicated genes is sufficient to explain regional HD atrophy, or whether the network transmission of protein products is required to explain them. We find that network models are capable of predicting, to a high degree, observed atrophy in human subjects. Lastly, we propose a model of anterograde network transmission, and show that it is the most parsimonious yet most likely to explain observed atrophy patterns in HD. Collectively, these data indicate that pathology spread in HD may be mediated by the brain's intrinsic structural network organization. This is the first study to systematically and quantitatively test multiple hypotheses of pathology spread in living human subjects with HD.
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Affiliation(s)
- Ashish Raj
- Department of Radiology and Biomedical Imaging, University of California at San Francisco, USA; UCSF-UC Berkeley Graduate Program in BioEngineering, University of California at San Francisco, USA; Department of Radiology, Weill Cornell Medical College of Cornell University, 407 E. 61 Street, RR106, New York, NY 10065, USA.
| | - Fon Powell
- Department of Radiology, Weill Cornell Medical College of Cornell University, 407 E. 61 Street, RR106, New York, NY 10065, USA
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13
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Sullivan DJ, Wu X, Gallo NR, Naughton NM, Georgiadis JG, Pelegri AA. Sensitivity analysis of effective transverse shear viscoelastic and diffusional properties of myelinated white matter. Phys Med Biol 2021; 66:035027. [PMID: 32599577 DOI: 10.1088/1361-6560/aba0cc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Motivated by the need to interpret the results from a combined use of in vivo brain Magnetic Resonance Elastography (MRE) and Diffusion Tensor Imaging (DTI), we developed a computational framework to study the sensitivity of single-frequency MRE and DTI metrics to white matter microstructure and cell-level mechanical and diffusional properties. White matter was modeled as a triphasic unidirectional composite, consisting of parallel cylindrical inclusions (axons) surrounded by sheaths (myelin), and embedded in a matrix (glial cells plus extracellular matrix). Only 2D mechanics and diffusion in the transverse plane (perpendicular to the axon direction) was considered, and homogenized (effective) properties were derived for a periodic domain containing a single axon. The numerical solutions of the MRE problem were performed with ABAQUS and by employing a sophisticated boundary-conforming grid generation scheme. Based on the linear viscoelastic response to harmonic shear excitation and steady-state diffusion in the transverse plane, a systematic sensitivity analysis of MRE metrics (effective transverse shear storage and loss moduli) and DTI metric (effective radial diffusivity) was performed for a wide range of microstructural and intrinsic (phase-based) physical properties. The microstructural properties considered were fiber volume fraction, and the myelin sheath/axon diameter ratio. The MRE and DTI metrics are very sensitive to the fiber volume fraction, and the intrinsic viscoelastic moduli of the glial phase. The MRE metrics are nonlinear functions of the fiber volume fraction, but the effective diffusion coefficient varies linearly with it. Finally, the transverse metrics of both MRE and DTI are insensitive to the axon diameter in steady state. Our results are consistent with the limited anisotropic MRE and co-registered DTI measurements, mainly in the corpus callosum, available in the literature. We conclude that isotropic MRE and DTI constitutive models are good approximations for myelinated white matter in the transverse plane. The unidirectional composite model presented here is used for the first time to model harmonic shear stress under MRE-relevant frequency on the cell level. This model can be extended to 3D in order to inform the solution of the inverse problem in MRE, establish the biological basis of MRE metrics, and integrate MRE/DTI with other modalities towards increasing the specificity of neuroimaging.
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Affiliation(s)
- Daniel J Sullivan
- Department of Mechanical and Aerospace Engineering, Rutgers, the State University of New Jersey, 98 Brett Road, Piscataway, NJ 08854-8058, United States of America
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14
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Gatto RG, Weissmann C. Diffusion Tensor Imaging in Preclinical and Human Studies of Huntington's Disease: What Have we Learned so Far? Curr Med Imaging 2020; 15:521-542. [PMID: 32008561 DOI: 10.2174/1573405614666181115113400] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/23/2018] [Accepted: 10/26/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Huntington's Disease is an irreversible neurodegenerative disease characterized by the progressive deterioration of specific brain nerve cells. The current evaluation of cellular and physiological events in patients with HD relies on the development of transgenic animal models. To explore such events in vivo, diffusion tensor imaging has been developed to examine the early macro and microstructural changes in brain tissue. However, the gap in diffusion tensor imaging findings between animal models and clinical studies and the lack of microstructural confirmation by histological methods has questioned the validity of this method. OBJECTIVE This review explores white and grey matter ultrastructural changes associated to diffusion tensor imaging, as well as similarities and differences between preclinical and clinical Huntington's Disease studies. METHODS A comprehensive review of the literature using online-resources was performed (Pub- Med search). RESULTS Similar changes in fractional anisotropy as well as axial, radial and mean diffusivities were observed in white matter tracts across clinical and animal studies. However, comparative diffusion alterations in different grey matter structures were inconsistent between clinical and animal studies. CONCLUSION Diffusion tensor imaging can be related to specific structural anomalies in specific cellular populations. However, some differences between animal and clinical studies could derive from the contrasting neuroanatomy or connectivity across species. Such differences should be considered before generalizing preclinical results into the clinical practice. Moreover, current limitations of this technique to accurately represent complex multicellular events at the single micro scale are real. Future work applying complex diffusion models should be considered.
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Affiliation(s)
- Rodolfo Gabriel Gatto
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, United States
| | - Carina Weissmann
- Insituto de Fisiología Biologia Molecular y Neurociencias-IFIBYNE-CONICET, University of Buenos Aires, Buenos Aires, Argentina
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15
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McColgan P, Joubert J, Tabrizi SJ, Rees G. The human motor cortex microcircuit: insights for neurodegenerative disease. Nat Rev Neurosci 2020; 21:401-415. [PMID: 32555340 DOI: 10.1038/s41583-020-0315-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2020] [Indexed: 12/22/2022]
Abstract
The human motor cortex comprises a microcircuit of five interconnected layers with different cell types. In this Review, we use a layer-specific and cell-specific approach to integrate physiological accounts of this motor cortex microcircuit with the pathophysiology of neurodegenerative diseases affecting motor functions. In doing so we can begin to link motor microcircuit pathology to specific disease stages and clinical phenotypes. Based on microcircuit physiology, we can make future predictions of axonal loss and microcircuit dysfunction. With recent advances in high-resolution neuroimaging we can then test these predictions in humans in vivo, providing mechanistic insights into neurodegenerative disease.
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Affiliation(s)
- Peter McColgan
- Huntington's Disease Research Centre, UCL Institute of Neurology, University College London, London, UK.
| | - Julie Joubert
- Huntington's Disease Research Centre, UCL Institute of Neurology, University College London, London, UK
| | - Sarah J Tabrizi
- Huntington's Disease Research Centre, UCL Institute of Neurology, University College London, London, UK.,Dementia Research Institute at UCL, London, UK
| | - Geraint Rees
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, University College London, London, UK.,UCL Institute of Cognitive Neuroscience, University College London, London, UK
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16
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Gatto RG, Weissmann C, Amin M, Finkielsztein A, Sumagin R, Mareci TH, Uchitel OD, Magin RL. Assessing neuraxial microstructural changes in a transgenic mouse model of early stage Amyotrophic Lateral Sclerosis by ultra-high field MRI and diffusion tensor metrics. Animal Model Exp Med 2020; 3:117-129. [PMID: 32613171 PMCID: PMC7323706 DOI: 10.1002/ame2.12112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 02/28/2020] [Accepted: 03/22/2020] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE Cell structural changes are one of the main features observed during the development of amyotrophic lateral sclerosis (ALS). In this work, we propose the use of diffusion tensor imaging (DTI) metrics to assess specific ultrastructural changes in the central nervous system during the early neurodegenerative stages of ALS. METHODS Ultra-high field MRI and DTI data at 17.6T were obtained from fixed, excised mouse brains, and spinal cords from ALS (G93A-SOD1) mice. RESULTS Changes in fractional anisotropy (FA) and linear, planar, and spherical anisotropy ratios (CL, CP, and CS, respectively) of the diffusion eigenvalues were measured in white matter (WM) and gray matter (GM) areas associated with early axonal degenerative processes (in both the brain and the spinal cord). Specifically, in WM structures (corpus callosum, corticospinal tract, and spinal cord funiculi) as the disease progressed, FA, CL, and CP values decreased, whereas CS values increased. In GM structures (prefrontal cortex, hippocampus, and central spinal cord) FA and CP decreased, whereas the CL and CS values were unchanged or slightly smaller. Histological studies of a fluorescent mice model (YFP, G93A-SOD1 mouse) corroborated the early alterations in neuronal morphology and axonal connectivity measured by DTI. CONCLUSIONS Changes in diffusion tensor shape were observed in this animal model at the early, nonsymptomatic stages of ALS. Further studies of CL, CP, and CS as imaging biomarkers should be undertaken to refine this neuroimaging tool for future clinical use in the detection of the early stages of ALS.
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Affiliation(s)
- Rodolfo G. Gatto
- Department of BioengineeringUniversity of Illinois at ChicagoChicagoILUSA
| | - Carina Weissmann
- Instituto de Fisiología Biologia Molecular y Neurociencias‐IFIBYNE‐CONICETUniversity of Buenos AiresBuenos AiresArgentina
| | - Manish Amin
- Department of BiochemistryNational High Magnetic Field LaboratoryUniversity of FloridaGainesvilleFLUSA
| | - Ariel Finkielsztein
- Department of PathologySchool of MedicineNorthwestern UniversityChicagoILUSA
| | - Ronen Sumagin
- Department of PathologySchool of MedicineNorthwestern UniversityChicagoILUSA
| | - Thomas H. Mareci
- Department of BiochemistryNational High Magnetic Field LaboratoryUniversity of FloridaGainesvilleFLUSA
| | - Osvaldo D. Uchitel
- Instituto de Fisiología Biologia Molecular y Neurociencias‐IFIBYNE‐CONICETUniversity of Buenos AiresBuenos AiresArgentina
| | - Richard L. Magin
- Department of BioengineeringUniversity of Illinois at ChicagoChicagoILUSA
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17
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Human Huntington's Disease iPSC-Derived Cortical Neurons Display Altered Transcriptomics, Morphology, and Maturation. Cell Rep 2019; 25:1081-1096.e6. [PMID: 30355486 DOI: 10.1016/j.celrep.2018.09.076] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 09/02/2018] [Accepted: 09/24/2018] [Indexed: 01/11/2023] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disease caused by an expanded CAG repeat in the Huntingtin (HTT) gene. Induced pluripotent stem cell (iPSC) models of HD provide an opportunity to study the mechanisms underlying disease pathology in disease-relevant patient tissues. Murine studies have demonstrated that HTT is intricately involved in corticogenesis. However, the effect of mutant Hungtintin (mtHTT) in human corticogenesis has not yet been thoroughly explored. This examination is critical, due to inherent differences in cortical development and timing between humans and mice. We therefore differentiated HD and non-diseased iPSCs into functional cortical neurons. While HD patient iPSCs can successfully differentiate toward a cortical fate in culture, the resulting neurons display altered transcriptomics, morphological and functional phenotypes indicative of altered corticogenesis in HD.
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18
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Bay HH, Özkan M, Onat F, Çavdar S. Do the Dento-Thalamic Connections of Genetic Absence Epilepsy Rats from Strasbourg Differ from Those of Control Wistar Rats? Brain Connect 2019; 9:703-710. [PMID: 31591912 DOI: 10.1089/brain.2019.0694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The thalamo-cortical circuit is important in the genesis of absence epilepsy. This circuit can be influenced by connecting pathways from various parts of central nervous system. The aim of the present study is to define the dento-thalamic connections in Wistar animals and compare the results with genetic absence epilepsy rats from Strasbourg (GAERS) using the biotinylated dextran amine (BDA) tracer. We injected BDA into the dentate nucleus of 13 (n = 6 Wistar and n = 7 GAERS) animals. The dento-thalamic connections in the Wistar animals were denser and were connected to a wider range of thalamic nuclei compared with GAERS. The dentate nucleus was bilaterally connected to the central (central medial [CM], paracentral [PC]), ventral (ventral medial [VM], ventral lateral [VL], and ventral posterior lateral [VPL]), and posterior (Po) thalamic nuclei in Wistar animals. The majority of these connections were dense contralaterally and scarce ipsilaterally. Contralateral connections were present with the parafascicular (PF), ventral posterior medial, ventral anterior (VA), and central lateral (CL) thalamic nuclei in Wistar animals. Whereas in GAERS, bilateral connections were observed with the VL and CM. Contralateral connections were present with the PC, VM, VA, and PF thalamic nuclei in GAERS. The CL, VPL, and Po thalamic nucleus connections were not observed in GAERS. The present study showed weak/deficit dento-thalamic connections in GAERS compared with control Wistar animals. The scarce information flow from the dentate nucleus to thalamus in GAERS may have a deficient modulatory role on the thalamus and thus may affect modulation of the thalamo-cortical circuit.
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Affiliation(s)
| | - Mazhar Özkan
- Department of Anatomy, Marmara University School of Medicine, Istanbul, Turkey
| | - Filiz Onat
- Department of Pharmacology and Clinic Pharmacology, Marmara University School of Medicine, Istanbul, Turkey
| | - Safiye Çavdar
- Department of Anatomy, Koç University School of Medicine, Istanbul, Turkey
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19
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Lipták N, Bősze Z, Hiripi L. GFP transgenic animals in biomedical research: a review of potential disadvantages. Physiol Res 2019; 68:525-530. [PMID: 31342754 DOI: 10.33549/physiolres.934227] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Green Fluorescent protein (GFP) transgenic animals are accepted tools for studying various physiological processes, including organ development and cell migration. However, several in vivo studies claimed that GFP may impair transgenic animals' health. Glomerulosclerosis was observed in transgenic mice and rabbits with ubiquitous reporter protein expression. Heart-specific GFP expression evoked dilated cardiomyopathy and altered cardiac function in transgenic mouse and zebrafish lines, respectively. Moreover, growth retardation and increased axon swelling were observed in GFP and yellow fluorescent protein (YFP) transgenic mice, respectively. This review will focus on the potential drawbacks of the applications of GFP transgenic animals in biomedical research.
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Affiliation(s)
- N Lipták
- NARIC-Agricultural Biotechnology Institute, Animal Biotechnology Department, Gödöllő, Hungary.
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20
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Gatto RG, Amin M, Finkielsztein A, Weissmann C, Barrett T, Lamoutte C, Uchitel O, Sumagin R, Mareci TH, Magin RL. Unveiling early cortical and subcortical neuronal degeneration in ALS mice by ultra-high field diffusion MRI. Amyotroph Lateral Scler Frontotemporal Degener 2019; 20:549-561. [DOI: 10.1080/21678421.2019.1620285] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Rodolfo G. Gatto
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA,
| | - Manish Amin
- Department of Biochemistry and Molecular Biology, National High Magnetic Field Laboratory, University of Florida, Gainesville, FL, USA,
| | - Ariel Finkielsztein
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA,
| | - Carina Weissmann
- Institute for Physiology, Molecular Biology and Neurosciences (IFIBYNE CONICET-UBA), Buenos Aires, Argentina,
| | - Thomas Barrett
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA, and
| | - Caroline Lamoutte
- Department of Microbiology, University of Florida, Gainesville, FL, USA
| | - Osvaldo Uchitel
- Institute for Physiology, Molecular Biology and Neurosciences (IFIBYNE CONICET-UBA), Buenos Aires, Argentina,
| | - Ronen Sumagin
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA,
| | - Thomas H. Mareci
- Department of Biochemistry and Molecular Biology, National High Magnetic Field Laboratory, University of Florida, Gainesville, FL, USA,
| | - Richard L. Magin
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA,
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21
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Marottoli FM, Priego M, Flores-Barrera E, Pisharody R, Zaldua S, Fan KD, Ekkurthi GK, Brady ST, Morfini GA, Tseng KY, Tai LM. EGF Treatment Improves Motor Behavior and Cortical GABAergic Function in the R6/2 Mouse Model of Huntington's Disease. Mol Neurobiol 2019; 56:7708-7718. [PMID: 31104296 DOI: 10.1007/s12035-019-1634-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/24/2019] [Indexed: 01/13/2023]
Abstract
Recent evidence indicates that disruption of epidermal growth factor (EGF) signaling by mutant huntingtin (polyQ-htt) may contribute to the onset of behavioral deficits observed in Huntington's disease (HD) through a variety of mechanisms, including cerebrovascular dysfunction. Yet, whether EGF signaling modulates the development of HD pathology and the associated behavioral impairments remain unclear. To gain insight on this issue, we used the R6/2 mouse model of HD to assess the impact of chronic EGF treatment on behavior, and cerebrovascular and cortical neuronal functions. We found that bi-weekly treatment with a low dose of EGF (300 µg/kg, i.p.) for 6 weeks was sufficient to effectively improve motor behavior in R6/2 mice and diminish mortality, compared to vehicle-treated littermates. These beneficial effects of EGF treatment were dissociated from changes in cerebrovascular leakiness, a result that was surprising given that EGF ameliorates this deficit in other neurodegenerative diseases. Rather, the beneficial effect of EGF on R6/2 mice behavior was concomitant with a marked amelioration of cortical GABAergic function. As GABAergic transmission in cortical circuits is disrupted in HD, these novel data suggest a potential mechanistic link between deficits in EGF signaling and GABAergic dysfunction in the progression of HD.
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Affiliation(s)
- Felecia M Marottoli
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Mercedes Priego
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Eden Flores-Barrera
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Rohan Pisharody
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Steve Zaldua
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Kelly D Fan
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Giri K Ekkurthi
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Kuei Y Tseng
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Leon M Tai
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA.
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22
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Gatto RG, Ye AQ, Colon-Perez L, Mareci TH, Lysakowski A, Price SD, Brady ST, Karaman M, Morfini G, Magin RL. Detection of axonal degeneration in a mouse model of Huntington's disease: comparison between diffusion tensor imaging and anomalous diffusion metrics. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 32:461-471. [PMID: 30771034 DOI: 10.1007/s10334-019-00742-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/31/2018] [Accepted: 01/29/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The goal of this work is to study the changes in white matter integrity in R6/2, a well-established animal model of Huntington's disease (HD) that are captured by ex vivo diffusion imaging (DTI) using a high field MRI (17.6 T). MATERIALS AND METHODS DTI and continuous time random walk (CTRW) models were used to fit changes in the diffusion-weighted signal intensity in the corpus callosum of controls and in R6/2 mice. RESULTS A significant 13% decrease in fractional anisotropy, a 7% increase in axial diffusion, and a 33% increase in radial diffusion were observed between R6/2 and control mice. No change was observed in the CTRW beta parameter, but a significant decrease in the alpha parameter (- 21%) was measured. Histological analysis of the corpus callosum showed a decrease in axonal organization, myelin alterations, and astrogliosis. Electron microscopy studies demonstrated ultrastructural changes in degenerating axons, such as an increase in tortuosity in the R6/2 mice. CONCLUSIONS DTI and CTRW diffusion models display quantitative changes associated with the microstructural alterations observed in the corpus callosum of the R6/2 mice. The observed increase in the diffusivity and decrease in the alpha CTRW parameter providing support for the use of these diffusion models for non-invasive detection of white matter alterations in HD.
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Affiliation(s)
- Rodolfo G Gatto
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA.,Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA
| | - Allen Q Ye
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA
| | - Luis Colon-Perez
- Department of Neurology and Behavior, University of California at Irvine, Irvine, CA, USA.,Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Thomas H Mareci
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Anna Lysakowski
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Steven D Price
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Muge Karaman
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, IL, USA
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Richard L Magin
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA.
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23
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Suelves N, Miguez A, López-Benito S, Barriga GGD, Giralt A, Alvarez-Periel E, Arévalo JC, Alberch J, Ginés S, Brito V. Early Downregulation of p75 NTR by Genetic and Pharmacological Approaches Delays the Onset of Motor Deficits and Striatal Dysfunction in Huntington's Disease Mice. Mol Neurobiol 2019; 56:935-953. [PMID: 29804232 DOI: 10.1007/s12035-018-1126-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 05/11/2018] [Indexed: 11/26/2022]
Abstract
Deficits in striatal brain-derived neurotrophic factor (BDNF) delivery and/or BDNF/tropomyosin receptor kinase B (TrkB) signaling may contribute to neurotrophic support reduction and selective early degeneration of striatal medium spiny neurons in Huntington's disease (HD). Furthermore, we and others have demonstrated that TrkB/p75NTR imbalance in vitro increases the vulnerability of striatal neurons to excitotoxic insults and induces corticostriatal synaptic alterations. We have now expanded these studies by analyzing the consequences of BDNF/TrkB/p75NTR imbalance in the onset of motor behavior and striatal neuropathology in HD mice. Our findings demonstrate for the first time that the onset of motor coordination abnormalities, in a full-length knock-in HD mouse model (KI), correlates with the reduction of BDNF and TrkB levels, along with an increase in p75NTR expression. Genetic normalization of p75NTR expression in KI mutant mice delayed the onset of motor deficits and striatal neuropathology, as shown by restored levels of striatal-enriched proteins and dendritic spine density and reduced huntingtin aggregation. We found that the BDNF/TrkB/p75NTR imbalance led to abnormal BDNF signaling, manifested as a diminished activation of TrkB-phospholipase C-gamma pathway but upregulation of c-Jun kinase pathway. Moreover, we confirmed the contribution of the proper balance of BDNF/TrkB/p75NTR on HD pathology by a pharmacological approach using fingolimod. We observed that chronic infusion of fingolimod normalizes p75NTR levels, which is likely to improve motor coordination and striatal neuropathology in HD transgenic mice. We conclude that downregulation of p75NTR expression can delay disease progression suggesting that therapeutic approaches aimed to restore the balance between BDNF, TrkB, and p75NTR could be promising to prevent motor deficits in HD.
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Affiliation(s)
- Nuria Suelves
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Andrés Miguez
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Saray López-Benito
- Department of Cell Biology and Pathology, Instituto de Neurociencias de Castilla y León (INCyL), University of Salamanca, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain
| | - Gerardo García-Díaz Barriga
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Albert Giralt
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Elena Alvarez-Periel
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan Carlos Arévalo
- Department of Cell Biology and Pathology, Instituto de Neurociencias de Castilla y León (INCyL), University of Salamanca, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), Salamanca, Spain
| | - Jordi Alberch
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Silvia Ginés
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Verónica Brito
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurosciències, Universitat de Barcelona, Barcelona, Spain.
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
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Gatto RG, Amin MY, Deyoung D, Hey M, Mareci TH, Magin RL. Ultra-High Field Diffusion MRI Reveals Early Axonal Pathology in Spinal Cord of ALS mice. Transl Neurodegener 2018; 7:20. [PMID: 30128146 PMCID: PMC6097419 DOI: 10.1186/s40035-018-0122-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 07/02/2018] [Indexed: 12/11/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a disease characterized by a progressive degeneration of motor neurons leading to paralysis. Our previous MRI diffusion tensor imaging studies detected early white matter changes in the spinal cords of mice carrying the G93A-SOD1 mutation. Here, we extend those studies using ultra-high field MRI (17.6 T) and fluorescent microscopy to investigate the appearance of early structural and connectivity changes in the spinal cords of ALS mice. Methods The spinal cords from presymptomatic and symptomatic mice (80 to 120 days of age) were scanned (ex-vivo) using diffusion-weighted MRI. The fractional anisotropy (FA), axial (AD) and radial (RD) diffusivities were calculated for axial slices from the thoracic, cervical and lumbar regions of the spinal cords. The diffusion parameters were compared with fluorescence microscopy and membrane cellular markers from the same tissue regions. Results At early stages of the disease (day 80) in the lumbar region, we found, a 19% decrease in FA, a 9% decrease in AD and a 35% increase in RD. Similar changes were observed in cervical and thoracic spinal cord regions. Differences between control and ALS mice groups at the symptomatic stages (day 120) were larger. Quantitative fluorescence microscopy at 80 days, demonstrated a 22% reduction in axonal area and a 22% increase in axonal density. Tractography and quantitative connectome analyses measured by edge weights showed a 52% decrease in the lumbar regions of the spinal cords of this ALS mice group. A significant increase in ADC (23.3%) in the ALS mice group was related to an increase in aquaporin markers. Conclusions These findings suggest that the combination of ultra-high field diffusion MRI with fluorescent ALS mice reporters is a useful approach to detect and characterize presymptomatic white matter micro-ultrastructural changes and axonal connectivity anomalies in ALS.
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Affiliation(s)
- Rodolfo G Gatto
- 1Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St. Rm 578 M/C 512, Chicago, IL 60612 USA
| | - Manish Y Amin
- 2Department of Physics, University of Florida, Gainesville, FL USA
| | - Daniel Deyoung
- 2Department of Physics, University of Florida, Gainesville, FL USA
| | - Matthew Hey
- 3Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL USA
| | - Thomas H Mareci
- 4Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL USA
| | - Richard L Magin
- 5Department of Bioengineering, University of Illinois at Chicago, Chicago, IL USA
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25
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Gatto RG, Li W, Gao J, Magin RL. In vivo diffusion MRI detects early spinal cord axonal pathology in a mouse model of amyotrophic lateral sclerosis. NMR IN BIOMEDICINE 2018; 31:e3954. [PMID: 30117615 DOI: 10.1002/nbm.3954] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 06/08/2023]
Abstract
Diffusion magnetic resonance imaging (MRI) exhibits contrast that identifies macro- and microstructural changes in neurodegenerative diseases. Previous studies have shown that MR diffusion tensor imaging (DTI) can observe changes in spinal cord white matter in animals and humans affected with symptomatic amyotrophic lateral sclerosis (ALS). The goal of this preclinical work was to investigate the sensitivity of DTI for the detection of signs of tissue damage before symptoms appear. High-field MRI data were acquired using a 9.4-T animal scanner to examine the spinal cord of an ALS mouse model at pre- and post-symptomatic stages (days 80 and 120, respectively). The MRI results were validated using yellow fluorescent protein (YFP) via optical microscopy of spinal cord tissue slices collected from the YFP,G93A-SOD1 mouse strain. DTI maps of diffusion-weighted imaging (DWI) signal intensity, mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) were computed for axial slices of the lumbar region of the spinal cord. Significant changes were observed in FA (6.7% decrease, p < 0.01), AD (19.5% decrease, p < 0.01) and RD (16.1% increase, p < 0.001) at postnatal day 80 (P80). These differences were correlated with changes in axonal fluorescence intensity and membrane cellular markers. This study demonstrates the value of DTI as a potential tool to detect the underlying pathological progression associated with ALS, and may accelerate the discovery of therapeutic strategies for patients with this disease.
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Affiliation(s)
- Rodolfo G Gatto
- University of Illinois at Chicago, Anatomy and Cell Biology, Chicago, IL, USA
| | - Weiguo Li
- University of Illinois at Chicago, Bioengineering, Chicago, IL, USA
| | - Jin Gao
- University of Illinois at Chicago, Bioengineering, Chicago, IL, USA
| | - Richard L Magin
- University of Illinois at Chicago, Bioengineering, Chicago, IL, USA
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26
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Winklewski PJ, Sabisz A, Naumczyk P, Jodzio K, Szurowska E, Szarmach A. Understanding the Physiopathology Behind Axial and Radial Diffusivity Changes-What Do We Know? Front Neurol 2018. [PMID: 29535676 PMCID: PMC5835085 DOI: 10.3389/fneur.2018.00092] [Citation(s) in RCA: 265] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The use of the diffusion tensor imaging (DTI) is rapidly growing in the neuroimaging field. Nevertheless, rigorously performed quantitative validation of DTI pathologic metrics remains very limited owing to the difficulty in co-registering quantitative histology findings with magnetic resonance imaging. The aim of this review is to summarize the existing state-of-the-art knowledge with respect to axial (λ║) and radial (λ┴) diffusivity as DTI markers of axonal and myelin damage, respectively. First, we provide technical background for DTI and briefly discuss the specific organization of white matter in bundles of axonal fibers running in parallel; this is the natural target for imaging based on diffusion anisotropy. Second, we discuss the four seminal studies that paved the way for considering axial (λ║) and radial (λ┴) diffusivity as potential in vivo surrogate markers of axonal and myelin damage, respectively. Then, we present difficulties in interpreting axial (λ║) and radial (λ┴) diffusivity in clinical conditions associated with inflammation, edema, and white matter fiber crossing. Finally, future directions are highlighted. In summary, DTI can reveal strategic information with respect to white matter tracts, disconnection mechanisms, and related symptoms. Axial (λ║) and radial (λ┴) diffusivity seem to provide quite consistent information in healthy subjects, and in pathological conditions with limited edema and inflammatory changes. DTI remains one of the most promising non-invasive diagnostic tools in medicine.
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Affiliation(s)
- Pawel J Winklewski
- Department of Human Physiology, Medical University of Gdańsk, Gdańsk, Poland.,Department of Clinical Anatomy and Physiology, Pomeranian University in Słupsk, Słupsk, Poland.,2-nd Department of Radiology, Medical University of Gdańsk, Gdańsk, Poland
| | - Agnieszka Sabisz
- 2-nd Department of Radiology, Medical University of Gdańsk, Gdańsk, Poland
| | | | | | - Edyta Szurowska
- 2-nd Department of Radiology, Medical University of Gdańsk, Gdańsk, Poland
| | - Arkadiusz Szarmach
- 2-nd Department of Radiology, Medical University of Gdańsk, Gdańsk, Poland
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27
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Rosas HD, Wilkens P, Salat DH, Mercaldo ND, Vangel M, Yendiki AY, Hersch SM. Complex spatial and temporally defined myelin and axonal degeneration in Huntington disease. NEUROIMAGE-CLINICAL 2018; 20:236-242. [PMID: 30090698 PMCID: PMC6078048 DOI: 10.1016/j.nicl.2018.01.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/04/2018] [Accepted: 01/23/2018] [Indexed: 01/10/2023]
Abstract
Although much prior work has focused on the basal ganglia and cortical pathology that defines Huntington's disease (HD), recent studies have also begun to characterize cerebral white matter damage (Rosas et al., 2006; Dumas et al., 2012; Poudel et al., 2014). In this study, we investigated differences in the large fascicular bundles of the cerebral white matter of gene-positive HD carriers, including pre-manifest individuals and early symptomatic patients, using recently developed diffusion tractography procedures. We examined eighteen major fiber bundles in 37 patients with early HD (average age 55.2 ± 11.5, 14 male, 23 female), 31 gene-positive, motor negative pre-symptomatic HD (PHD) (average age 48.1 ± 11.5, 13 male, 18 female), and 38 healthy age-matched controls (average age 55.7 ± 8.6, 14 male, 24 female), using the TRActs Constrained by UnderLying Anatomy (TRACULA) procedure available as part of the FreeSurfer image processing software package. We calculated the mean fractional anisotropy (FA) and the mean radial (RD) and axial diffusivities (AD) for each fiber bundle. We also evaluated the relationships between diffusion measures, cognition and regional cortical thinning. We found that early changes in RD of select tracts in PHD subjects were associated with impaired performance on neuropsychological tests, suggesting that early changes in myelin might underlie early cognitive dysfunction. Finally, we found that increases in AD of select tracts were associated with regionally select cortical thinning of areas known to atrophy in HD, including the sensorimotor, supramarginal and fusiform gyrus, suggesting that AD may be reflecting pyramidal cell degeneration in HD. Together, these results suggest that white matter microstructural changes in HD reflect a complex, clinically relevant and dynamic process. In our study, we found evidence of a temporally specific and regionally selective degeneration of white matter (WM) bundles. Early changes in myelin integrity were found in pre-manifest HD; these correlated with cognitive scores but not with atrophy. In contrast, changes in axonal integrity were found later, in early HD; these correlated closely with cortical atrophy. These findings bring new insights into WM degeneration in HD, its clinical significance and suggest novel therapeutic targets.
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Affiliation(s)
- H D Rosas
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Center for Neuro-imaging of Aging and Neurodegenerative Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - P Wilkens
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Center for Neuro-imaging of Aging and Neurodegenerative Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - D H Salat
- Center for Neuro-imaging of Aging and Neurodegenerative Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, USA
| | - N D Mercaldo
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - M Vangel
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Biostatistics, Massachusetts General Hospital, Boston, MA, USA
| | - A Y Yendiki
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, USA
| | - S M Hersch
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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28
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Genetic Rodent Models of Huntington Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1049:29-57. [DOI: 10.1007/978-3-319-71779-1_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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29
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Gatto RG, Mustafi SM, Amin MY, Mareci TH, Wu YC, Magin RL. Neurite orientation dispersion and density imaging can detect presymptomatic axonal degeneration in the spinal cord of ALS mice. FUNCTIONAL NEUROLOGY 2018; 33:155-163. [PMID: 30457969 PMCID: PMC7212765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Neurite orientation dispersion and density imaging (NODDI), a MRI multi-shell diffusion technique, has offered new insights for the study of microstructural changes in neurodegenerative diseases. Mainly, the present study aimed to determine the connection between NODDI-derived parameters and changes in white matter (WM) abnormalities at early stages of amyotrophic lateral sclerosis (ALS). Spinal cords from ALS mice (G93A-SOD1 mice) were scanned in a Bruker Avance III HD 17.6T magnet. Fluorescent axonal-tagged mice (YFP, G93A-SOD1 mice) were used for quantitative histological analysis. NODDI showed a decrease in intra-cellular volume fraction (-24%) and increases in orientation dispersion index (+35%) and isotropic volume fraction (+33%). In addition, histoathological results demonstrated a reductions in axonal area (-11%) and myelin content (-29%). A histological decrease in WM intra-axonal space (-71%) and an increase in the extra-axonal compartment (+22%) were also detected. Our studies demonstrate that NODDI may be a suitable technique for detecting presymptomatic spinal cord WM microstructural degeneration in ALS.
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Affiliation(s)
- Rodolfo G. Gatto
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Sourajit M. Mustafi
- Department of Radiology and Imaging Sciences, Indiana University, School of Medicine Indianapolis, IN, USA
| | - Manish Y. Amin
- Department of Physics, University of Florida, Gainesville, FL, USA
| | - Thomas H. Mareci
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Yu-Chien Wu
- Department of Radiology and Imaging Sciences, Indiana University, School of Medicine Indianapolis, IN, USA
| | - Richard L. Magin
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
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30
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Gatto RG. Diffusion tensor imaging as a tool to detect presymptomatic axonal degeneration in a preclinical spinal cord model of amyotrophic lateral sclerosis. Neural Regen Res 2018; 13:425-426. [PMID: 29623925 PMCID: PMC5900503 DOI: 10.4103/1673-5374.228723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Rodolfo Gabriel Gatto
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
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31
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Virlogeux A, Moutaux E, Christaller W, Genoux A, Bruyère J, Fino E, Charlot B, Cazorla M, Saudou F. Reconstituting Corticostriatal Network on-a-Chip Reveals the Contribution of the Presynaptic Compartment to Huntington’s Disease. Cell Rep 2018; 22:110-122. [DOI: 10.1016/j.celrep.2017.12.013] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 11/01/2017] [Accepted: 12/01/2017] [Indexed: 10/18/2022] Open
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32
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Garcia-Miralles M, Geva M, Tan JY, Yusof NABM, Cha Y, Kusko R, Tan LJ, Xu X, Grossman I, Orbach A, Hayden MR, Pouladi MA. Early pridopidine treatment improves behavioral and transcriptional deficits in YAC128 Huntington disease mice. JCI Insight 2017; 2:95665. [PMID: 29212949 DOI: 10.1172/jci.insight.95665] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/01/2017] [Indexed: 12/31/2022] Open
Abstract
Pridopidine is currently under clinical development for Huntington disease (HD), with on-going studies to better characterize its therapeutic benefit and mode of action. Pridopidine was administered either prior to the appearance of disease phenotypes or in advanced stages of disease in the YAC128 mouse model of HD. In the early treatment cohort, animals received 0, 10, or 30 mg/kg pridopidine for a period of 10.5 months. In the late treatment cohort, animals were treated for 8 weeks with 0 mg/kg or an escalating dose of pridopidine (10 to 30 mg/kg over 3 weeks). Early treatment improved motor coordination and reduced anxiety- and depressive-like phenotypes in YAC128 mice, but it did not rescue striatal and corpus callosum atrophy. Late treatment, conversely, only improved depressive-like symptoms. RNA-seq analysis revealed that early pridopidine treatment reversed striatal transcriptional deficits, upregulating disease-specific genes that are known to be downregulated during HD, a finding that is experimentally confirmed herein. This suggests that pridopidine exerts beneficial effects at the transcriptional level. Taken together, our findings support continued clinical development of pridopidine for HD, particularly in the early stages of disease, and provide valuable insight into the potential therapeutic mode of action of pridopidine.
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Affiliation(s)
- Marta Garcia-Miralles
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore
| | - Michal Geva
- Teva Pharmaceutical Industries Ltd., Petach Tikva, Israel
| | - Jing Ying Tan
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore
| | | | - Yoonjeong Cha
- Immuneering Corporation, Cambridge, Massachusetts, USA
| | - Rebecca Kusko
- Immuneering Corporation, Cambridge, Massachusetts, USA
| | - Liang Juin Tan
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore
| | - Xiaohong Xu
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore
| | - Iris Grossman
- Teva Pharmaceutical Industries Ltd., Petach Tikva, Israel
| | - Aric Orbach
- Teva Pharmaceutical Industries Ltd., Petach Tikva, Israel
| | - Michael R Hayden
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore.,Teva Pharmaceutical Industries Ltd., Petach Tikva, Israel.,Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Mahmoud A Pouladi
- Translational Laboratory in Genetic Medicine, Agency for Science, Technology and Research, Singapore (A*STAR), Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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33
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Gatto RG, Li W, Magin RL. Diffusion tensor imaging identifies presymptomatic axonal degeneration in the spinal cord of ALS mice. Brain Res 2017; 1679:45-52. [PMID: 29175489 DOI: 10.1016/j.brainres.2017.11.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/14/2017] [Accepted: 11/18/2017] [Indexed: 12/11/2022]
Abstract
Extensive pathological evidence indicates that axonal degeneration represents an early and critical event in amyotrophic lateral sclerosis (ALS). Unfortunately, few MRI studies have focused in the early detection of white matter (WM) alterations in the spinal cord region. To unveil these WM changes, we performed high resolution diffusion tensor imaging (DTI) and correlated the results with histological analysis of adjacent slices taken from the spinal cords of presymptomatic mice. The DTI studies demonstrated a significant reduction in fractional anisotropy (FA) as well as axial diffusivities (AD) and an increase in radial diffusivity (RD), predominantly at lower segments of the spinal cord. Increases in FA and a reduction in AD and RD were observed in spinal cord (SC) gray matter (GM). Diffusion changes are associated with early and progressive alterations in axonal connectivity following a distal to proximal progression. Histological data tagging neuronal, axonal and glial cell markers demonstrated presymptomatic alterations in spinal cord WM and GM. This study demonstrates that DTI methods are optimal preclinical imaging tools to detect structural anomalies in WM and GM spinal cord during early stages of the disease.
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Affiliation(s)
- Rodolfo G Gatto
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, College of Medicine, Chicago, IL 60612, USA.
| | - Weiguo Li
- Department of Bioengineering, University of Illinois at Chicago, School of Engineering, Chicago, IL 60612, USA
| | - Richard L Magin
- Department of Bioengineering, University of Illinois at Chicago, School of Engineering, Chicago, IL 60612, USA
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34
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Veldman MB, Yang XW. Molecular insights into cortico-striatal miscommunications in Huntington's disease. Curr Opin Neurobiol 2017; 48:79-89. [PMID: 29125980 DOI: 10.1016/j.conb.2017.10.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 10/18/2017] [Indexed: 12/12/2022]
Abstract
Huntington's disease (HD), a dominantly inherited neurodegenerative disease, is defined by its genetic cause, a CAG-repeat expansion in the HTT gene, its motor and psychiatric symptomology and primary loss of striatal medium spiny neurons (MSNs). However, the molecular mechanisms from genetic lesion to disease phenotype remain largely unclear. Mouse models of HD have been created that exhibit phenotypes partially recapitulating those in the patient, and specifically, cortico-striatal disconnectivity appears to be a shared pathogenic event shared by HD mouse models and patients. Molecular studies have begun to unveil converging molecular and cellular pathogenic mechanisms that may account for cortico-striatal miscommunication in various HD mouse models. Systems biological approaches help to illuminate synaptic molecular networks as a nexus for HD cortio-striatal pathogenesis, and may offer new candidate targets to modify the disease.
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Affiliation(s)
- Matthew B Veldman
- Center for Neurobehavioral Genetics and Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, United States; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, United States
| | - X William Yang
- Center for Neurobehavioral Genetics and Semel Institute for Neuroscience & Human Behavior, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, United States; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, United States.
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35
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Kneynsberg A, Combs B, Christensen K, Morfini G, Kanaan NM. Axonal Degeneration in Tauopathies: Disease Relevance and Underlying Mechanisms. Front Neurosci 2017; 11:572. [PMID: 29089864 PMCID: PMC5651019 DOI: 10.3389/fnins.2017.00572] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/29/2017] [Indexed: 12/14/2022] Open
Abstract
Tauopathies are a diverse group of diseases featuring progressive dying-back neurodegeneration of specific neuronal populations in association with accumulation of abnormal forms of the microtubule-associated protein tau. It is well-established that the clinical symptoms characteristic of tauopathies correlate with deficits in synaptic function and neuritic connectivity early in the course of disease, but mechanisms underlying these critical pathogenic events are not fully understood. Biochemical in vitro evidence fueled the widespread notion that microtubule stabilization represents tau's primary biological role and that the marked atrophy of neurites observed in tauopathies results from loss of microtubule stability. However, this notion contrasts with the mild phenotype associated with tau deletion. Instead, an analysis of cellular hallmarks common to different tauopathies, including aberrant patterns of protein phosphorylation and early degeneration of axons, suggests that alterations in kinase-based signaling pathways and deficits in axonal transport (AT) associated with such alterations contribute to the loss of neuronal connectivity triggered by pathogenic forms of tau. Here, we review a body of literature providing evidence that axonal pathology represents an early and common pathogenic event among human tauopathies. Observations of axonal degeneration in animal models of specific tauopathies are discussed and similarities to human disease highlighted. Finally, we discuss potential mechanistic pathways other than microtubule destabilization by which disease-related forms of tau may promote axonopathy.
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Affiliation(s)
- Andrew Kneynsberg
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Benjamin Combs
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Kyle Christensen
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Nicholas M Kanaan
- Neuroscience Program, Michigan State University, East Lansing, MI, United States.,Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI, United States.,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, MI, United States
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36
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Salvadores N, Sanhueza M, Manque P, Court FA. Axonal Degeneration during Aging and Its Functional Role in Neurodegenerative Disorders. Front Neurosci 2017; 11:451. [PMID: 28928628 PMCID: PMC5591337 DOI: 10.3389/fnins.2017.00451] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/25/2017] [Indexed: 12/11/2022] Open
Abstract
Aging constitutes the main risk factor for the development of neurodegenerative diseases. This represents a major health issue worldwide that is only expected to escalate due to the ever-increasing life expectancy of the population. Interestingly, axonal degeneration, which occurs at early stages of neurodegenerative disorders (ND) such as Alzheimer's disease, Amyotrophic lateral sclerosis, and Parkinson's disease, also takes place as a consequence of normal aging. Moreover, the alteration of several cellular processes such as proteostasis, response to cellular stress and mitochondrial homeostasis, which have been described to occur in the aging brain, can also contribute to axonal pathology. Compelling evidence indicate that the degeneration of axons precedes clinical symptoms in NDs and occurs before cell body loss, constituting an early event in the pathological process and providing a potential therapeutic target to treat neurodegeneration before neuronal cell death. Although, normal aging and the development of neurodegeneration are two processes that are closely linked, the molecular basis of the switch that triggers the transition from healthy aging to neurodegeneration remains unrevealed. In this review we discuss the potential role of axonal degeneration in this transition and provide a detailed overview of the literature and current advances in the molecular understanding of the cellular changes that occur during aging that promote axonal degeneration and then discuss this in the context of ND.
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Affiliation(s)
- Natalia Salvadores
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
| | - Mario Sanhueza
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
| | - Patricio Manque
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile
| | - Felipe A Court
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
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Fern R. The Leukocentric Theory of Neurological Disorder: A Manifesto. Neurochem Res 2017; 42:2666-2672. [DOI: 10.1007/s11064-017-2279-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/12/2017] [Accepted: 04/21/2017] [Indexed: 01/26/2023]
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Brady ST, Morfini GA. Regulation of motor proteins, axonal transport deficits and adult-onset neurodegenerative diseases. Neurobiol Dis 2017; 105:273-282. [PMID: 28411118 DOI: 10.1016/j.nbd.2017.04.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/17/2017] [Accepted: 04/10/2017] [Indexed: 01/07/2023] Open
Abstract
Neurons affected in a wide variety of unrelated adult-onset neurodegenerative diseases (AONDs) typically exhibit a "dying back" pattern of degeneration, which is characterized by early deficits in synaptic function and neuritic pathology long before neuronal cell death. Consistent with this observation, multiple unrelated AONDs including Alzheimer's disease, Parkinson's disease, Huntington's disease, and several motor neuron diseases feature early alterations in kinase-based signaling pathways associated with deficits in axonal transport (AT), a complex cellular process involving multiple intracellular trafficking events powered by microtubule-based motor proteins. These pathogenic events have important therapeutic implications, suggesting that a focus on preservation of neuronal connections may be more effective to treat AONDs than addressing neuronal cell death. While the molecular mechanisms underlying AT abnormalities in AONDs are still being analyzed, evidence has accumulated linking those to a well-established pathological hallmark of multiple AONDs: altered patterns of neuronal protein phosphorylation. Here, we present a short overview on the biochemical heterogeneity of major motor proteins for AT, their regulation by protein kinases, and evidence revealing cell type-specific AT specializations. When considered together, these findings may help explain how independent pathogenic pathways can affect AT differentially in the context of each AOND.
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Affiliation(s)
- Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
| | - Gerardo A Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA 02543, USA.
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ALS-linked FUS exerts a gain of toxic function involving aberrant p38 MAPK activation. Sci Rep 2017; 7:115. [PMID: 28273913 PMCID: PMC5428330 DOI: 10.1038/s41598-017-00091-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 01/30/2017] [Indexed: 12/14/2022] Open
Abstract
Mutations in Fused in Sarcoma/Translocated in Liposarcoma (FUS) cause familial forms of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive axonal degeneration mainly affecting motor neurons. Evidence from transgenic mouse models suggests mutant forms of FUS exert an unknown gain-of-toxic function in motor neurons, but mechanisms underlying this effect remain unknown. Towards this end, we studied the effect of wild type FUS (FUS WT) and three ALS-linked variants (G230C, R521G and R495X) on fast axonal transport (FAT), a cellular process critical for appropriate maintenance of axonal connectivity. All ALS-FUS variants impaired anterograde and retrograde FAT in squid axoplasm, whereas FUS WT had no effect. Misfolding of mutant FUS is implicated in this process, as the molecular chaperone Hsp110 mitigated these toxic effects. Interestingly, mutant FUS-induced impairment of FAT in squid axoplasm and of axonal outgrowth in mammalian primary motor neurons involved aberrant activation of the p38 MAPK pathway, as also reported for ALS-linked forms of Cu, Zn superoxide dismutase (SOD1). Accordingly, increased levels of active p38 MAPK were detected in post-mortem human ALS-FUS brain tissues. These data provide evidence for a novel gain-of-toxic function for ALS-linked FUS involving p38 MAPK activation.
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Di Pardo A, Amico E, Maglione V. Impaired Levels of Gangliosides in the Corpus Callosum of Huntington Disease Animal Models. Front Neurosci 2016; 10:457. [PMID: 27766070 PMCID: PMC5052274 DOI: 10.3389/fnins.2016.00457] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 09/21/2016] [Indexed: 12/18/2022] Open
Abstract
Huntington Disease (HD) is a genetic neurodegenerative disorder characterized by broad types of cellular and molecular dysfunctions that may affect both neuronal and non-neuronal cell populations. Among all the molecular mechanisms underlying the complex pathogenesis of the disease, alteration of sphingolipids has been identified as one of the most important determinants in the last years. In the present study, besides the purpose of further confirming the evidence of perturbed metabolism of gangliosides GM1, GD1a, and GT1b the most abundant cerebral glycosphingolipids, in the striatal and cortical tissues of HD transgenic mice, we aimed to test the hypothesis that abnormal levels of these lipids may be found also in the corpus callosum white matter, a ganglioside-enriched brain region described being dysfunctional early in the disease. Semi-quantitative analysis of GM1, GD1a, and GT1b content indicated that ganglioside metabolism is a common feature in two different HD animal models (YAC128 and R6/2 mice) and importantly, demonstrated that levels of these gangliosides were significantly reduced in the corpus callosum white matter of both models starting from the early stages of the disease. Besides corroborating the evidence of aberrant ganglioside metabolism in HD, here, we found out for the first time, that ganglioside dysfunction is an early event in HD models and it may potentially represent a critical molecular change influencing the pathogenesis of the disease.
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Affiliation(s)
- Alba Di Pardo
- Istituto Neurologico Mediterraneo (IRCCS) Neuromed Pozzilli, Italy
| | - Enrico Amico
- Istituto Neurologico Mediterraneo (IRCCS) Neuromed Pozzilli, Italy
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41
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Steventon JJ, Trueman RC, Ma D, Yhnell E, Bayram-Weston Z, Modat M, Cardoso J, Ourselin S, Lythgoe M, Stewart A, Rosser AE, Jones DK. Longitudinal in vivo MRI in a Huntington's disease mouse model: Global atrophy in the absence of white matter microstructural damage. Sci Rep 2016; 6:32423. [PMID: 27581950 PMCID: PMC5007531 DOI: 10.1038/srep32423] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 08/05/2016] [Indexed: 12/20/2022] Open
Abstract
Huntington’s disease (HD) is a genetically-determined neurodegenerative disease. Characterising neuropathology in mouse models of HD is commonly restricted to cross-sectional ex vivo analyses, beset by tissue fixation issues. In vivo longitudinal magnetic resonance imaging (MRI) allows for disease progression to be probed non-invasively. In the HdhQ150 mouse model of HD, in vivo MRI was employed at two time points, before and after the onset of motor signs, to assess brain macrostructure and white matter microstructure. Ex vivo MRI, immunohistochemistry, transmission electron microscopy and behavioural testing were also conducted. Global brain atrophy was found in HdhQ150 mice at both time points, with no neuropathological progression across time and a selective sparing of the cerebellum. In contrast, no white matter abnormalities were detected from the MRI images or electron microscopy images alike. The relationship between motor function and MR-based structural measurements was different for the HdhQ150 and wild-type mice, although there was no relationship between motor deficits and histopathology. Widespread neuropathology prior to symptom onset is consistent with patient studies, whereas the absence of white matter abnormalities conflicts with patient data. The myriad reasons for this inconsistency require further attention to improve the translatability from mouse models of disease.
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Affiliation(s)
- Jessica J Steventon
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Park Place, Cardiff, CF10 3AT, UK.,Brain Repair Group, Life Science Building, 3rd Floor, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.,Neuroscience and Mental Health Research Institute, Cardiff University, Hadyn Ellis Building, Cathays, Cardiff, CF24 4HQ, UK.,Experimental MRI Centre, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Rebecca C Trueman
- Brain Repair Group, Life Science Building, 3rd Floor, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.,School of Life Sciences, Queen's Medical Centre, Nottingham University, Nottingham, NG7 2UH, UK
| | - Da Ma
- Centre for Medical Imaging Computing, University College London, London, UK.,Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, UK
| | - Emma Yhnell
- Brain Repair Group, Life Science Building, 3rd Floor, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.,Neuroscience and Mental Health Research Institute, Cardiff University, Hadyn Ellis Building, Cathays, Cardiff, CF24 4HQ, UK
| | - Zubeyde Bayram-Weston
- Brain Repair Group, Life Science Building, 3rd Floor, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.,Neuroscience and Mental Health Research Institute, Cardiff University, Hadyn Ellis Building, Cathays, Cardiff, CF24 4HQ, UK
| | - Marc Modat
- Centre for Medical Imaging Computing, University College London, London, UK
| | - Jorge Cardoso
- Centre for Medical Imaging Computing, University College London, London, UK
| | - Sebastian Ourselin
- Centre for Medical Imaging Computing, University College London, London, UK
| | - Mark Lythgoe
- Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, UK
| | - Andrew Stewart
- Experimental MRI Centre, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Anne E Rosser
- Brain Repair Group, Life Science Building, 3rd Floor, School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK.,Neuroscience and Mental Health Research Institute, Cardiff University, Hadyn Ellis Building, Cathays, Cardiff, CF24 4HQ, UK.,Institute of Psychological Medicine and Neurology, School of Medicine, Hadyn Ellis Building, Maindy Road, Cathays, Cardiff CF24 4HQ, UK
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Park Place, Cardiff, CF10 3AT, UK.,Neuroscience and Mental Health Research Institute, Cardiff University, Hadyn Ellis Building, Cathays, Cardiff, CF24 4HQ, UK
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Raymond LA. Striatal synaptic dysfunction and altered calcium regulation in Huntington disease. Biochem Biophys Res Commun 2016; 483:1051-1062. [PMID: 27423394 DOI: 10.1016/j.bbrc.2016.07.058] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 07/11/2016] [Indexed: 11/30/2022]
Abstract
Synaptic dysfunction and altered calcium homeostasis in the brain is common to many neurodegenerative disorders. Among these, Huntington disease (HD), which is inherited in an autosomal dominant fashion, can serve as a model for investigating these mechanisms. HD generally manifests in middle age as a disorder of movement, mood and cognition. An expanded polymorphic CAG repeat in the HTT gene results in progressive neurodegeneration that impacts striatal spiny projection neurons (SPNs) earliest and most severely. Striatal SPNs receive massive glutamatergic input from cortex and thalamus, and these excitatory synapses are a focus for early changes that can trigger aberrant downstream signaling to disrupt synaptic plasticity and lead to later degeneration. Mitochondrial dysfunction and altered intracellular calcium-induced calcium release and sequestration mechanisms add to the impairments in circuit function that may underlie prodromal cognitive and subtle motor deficits. These mechanisms and implications for developing disease-modifying therapy will be reviewed here.
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Affiliation(s)
- Lynn A Raymond
- Department of Psychiatry and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 4834-2255 Wesbrook Mall, Vancouver, BC, Canada, V6T 1Z3.
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