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Ferrer I. Historical review: The golden age of the Golgi method in human neuropathology. J Neuropathol Exp Neurol 2024; 83:375-395. [PMID: 38622902 DOI: 10.1093/jnen/nlae031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024] Open
Abstract
Golgi methods were used to study human neuropathology in the 1970s, 1980s, and 1990s of the last century. Although a relatively small number of laboratories applied these methods, their impact was crucial by increasing knowledge about: (1) the morphology, orientation, and localization of neurons in human cerebral and cerebellar malformations and ganglionic tumors, and (2) the presence of abnormal structures including large and thin spines (spine dysgenesis) in several disorders linked to mental retardation, focal enlargements of the axon hillock and dendrites (meganeurites) in neuronal storage diseases, growth cone-like appendages in Alzheimer disease, as well as abnormal structures in other dementias. Although there were initial concerns about their reliability, reduced dendritic branches and dendritic spines were identified as common alterations in mental retardation, dementia, and other pathological conditions. Similar observations in appropriate experimental models have supported many abnormalities that were first identified using Golgi methods in human material. Moreover, electron microscopy, immunohistochemistry, fluorescent tracers, and combined methods have proven the accuracy of pioneering observations uniquely visualized as 3D images of fully stained individual neurons. Although Golgi methods had their golden age many years ago, these methods may still be useful complementary tools in human neuropathology.
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Affiliation(s)
- Isidro Ferrer
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Hospitalet de LLobregat, Spain
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Morrison LM, Huang H, Handler HP, Fu M, Bushart DD, Pappas SS, Orr HT, Shakkottai VG. Increased intrinsic membrane excitability is associated with hypertrophic olivary degeneration in spinocerebellar ataxia type 1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.23.563657. [PMID: 37961407 PMCID: PMC10634770 DOI: 10.1101/2023.10.23.563657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
One of the characteristic areas of brainstem degeneration across multiple spinocerebellar ataxias (SCAs) is the inferior olive (IO), a medullary nucleus that plays a key role in motor learning. In addition to its vulnerability in SCAs, the IO is also susceptible to a distinct pathology known as hypertrophic olivary degeneration (HOD). Clinically, HOD has been exclusively observed after lesions in the brainstem disrupt inhibitory afferents to the IO. Here, for the first time, we describe HOD in another context: spinocerebellar ataxia type 1 (SCA1). Using the genetically-precise SCA1 knock-in mouse model (SCA1-KI; both sexes used), we assessed SCA1-associated changes in IO neuron structure and function. Concurrent with degeneration, we found that SCA1-KI IO neurons are hypertrophic, exhibiting early dendrite lengthening and later somatic expansion. Unlike in previous descriptions of HOD, we observed no clear loss of IO inhibitory innervation; nevertheless, patch-clamp recordings from brainstem slices reveal that SCA1-KI IO neurons are hyperexcitable. Rather than synaptic disinhibition, we identify increases in intrinsic membrane excitability as the more likely mechanism underlying this novel SCA1 phenotype. Specifically, transcriptome analysis indicates that SCA1-KI IO hyperexcitability is associated with a reduced medullary expression of ion channels responsible for spike afterhyperpolarization (AHP) in IO neurons - a result that has a functional consequence, as SCA1-KI IO neuron spikes exhibit a diminished AHP. These results reveal membrane excitability as a potential link between disparate causes of IO degeneration, suggesting that HOD can result from any cause, intrinsic or extrinsic, that increases excitability of the IO neuron membrane.
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Affiliation(s)
- Logan M. Morrison
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Haoran Huang
- Medical Scientist Training Program, The Ohio State University, Columbus, OH 43210 USA
- College of Medicine, The Ohio State University, Columbus, OH 43210 USA
| | - Hillary P. Handler
- Molecular Diagnostics Laboratory, University of Minnesota Fairview Medical Center, Minneapolis, MN 55455, USA
| | - Min Fu
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - David D. Bushart
- College of Medicine, The Ohio State University, Columbus, OH 43210 USA
| | - Samuel S. Pappas
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Harry T. Orr
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Vikram G. Shakkottai
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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3
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Chopra R, Bushart DD, Cooper JP, Yellajoshyula D, Morrison LM, Huang H, Handler HP, Man LJ, Dansithong W, Scoles DR, Pulst SM, Orr HT, Shakkottai VG. Altered Capicua expression drives regional Purkinje neuron vulnerability through ion channel gene dysregulation in spinocerebellar ataxia type 1. Hum Mol Genet 2020; 29:3249-3265. [PMID: 32964235 PMCID: PMC7689299 DOI: 10.1093/hmg/ddaa212] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/19/2020] [Accepted: 09/17/2020] [Indexed: 12/22/2022] Open
Abstract
Selective neuronal vulnerability in neurodegenerative disease is poorly understood. Using the ATXN1[82Q] model of spinocerebellar ataxia type 1 (SCA1), we explored the hypothesis that regional differences in Purkinje neuron degeneration could provide novel insights into selective vulnerability. ATXN1[82Q] Purkinje neurons from the anterior cerebellum were found to degenerate earlier than those from the nodular zone, and this early degeneration was associated with selective dysregulation of ion channel transcripts and altered Purkinje neuron spiking. Efforts to understand the basis for selective dysregulation of channel transcripts revealed modestly increased expression of the ATXN1 co-repressor Capicua (Cic) in anterior cerebellar Purkinje neurons. Importantly, disrupting the association between ATXN1 and Cic rescued the levels of these ion channel transcripts, and lentiviral overexpression of Cic in the nodular zone accelerated both aberrant Purkinje neuron spiking and neurodegeneration. These findings reinforce the central role for Cic in SCA1 cerebellar pathophysiology and suggest that only modest reductions in Cic are needed to have profound therapeutic impact in SCA1.
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Affiliation(s)
- Ravi Chopra
- Medical Scientist Training Program, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Neurology, Washington University in St. Louis, Saint Louis, MO 63110, USA
| | - David D Bushart
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
- Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - John P Cooper
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | | | - Logan M Morrison
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Haoran Huang
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Hillary P Handler
- Department of Laboratory Medicine and Pathology, Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Luke J Man
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Harry T Orr
- Department of Laboratory Medicine and Pathology, Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Vikram G Shakkottai
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
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Dendritic potassium channel dysfunction may contribute to dendrite degeneration in spinocerebellar ataxia type 1. PLoS One 2018; 13:e0198040. [PMID: 29847609 PMCID: PMC5976172 DOI: 10.1371/journal.pone.0198040] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 05/11/2018] [Indexed: 12/14/2022] Open
Abstract
Purkinje neuron dendritic degeneration precedes cell loss in cerebellar ataxia, but the basis for dendritic vulnerability in ataxia remains poorly understood. Recent work has suggested that potassium (K+) channel dysfunction and consequent spiking abnormalities contribute to Purkinje neuron degeneration, but little attention has been paid to how K+ channel dysfunction impacts dendritic excitability and the role this may play in the degenerative process. We examined the relationship between K+ channel dysfunction, dendritic excitability and dendritic degeneration in spinocerebellar ataxia type 1 (SCA1). Examination of published RNA sequencing data from SCA1 mice revealed reduced expression of several K+ channels that are important regulators of excitability in Purkinje neuron dendrites. Patch clamp recordings in Purkinje neurons from SCA1 mice identified increased dendritic excitability in the form of enhanced back-propagation of action potentials and an increased propensity to produce dendritic calcium spikes. Dendritic excitability could be rescued by restoring expression of large-conductance calcium-activated potassium (BK) channels and activating other K+ channels with baclofen. Importantly, this treatment combination improves motor performance and mitigates dendritic degeneration in SCA1 mice. These results suggest that reduced expression of K+ channels results in persistently increased dendritic excitability at all stages of disease in SCA1, which in turn may contribute to the dendritic degeneration that precedes cell loss.
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Bushart DD, Chopra R, Singh V, Murphy GG, Wulff H, Shakkottai VG. Targeting potassium channels to treat cerebellar ataxia. Ann Clin Transl Neurol 2018; 5:297-314. [PMID: 29560375 PMCID: PMC5846455 DOI: 10.1002/acn3.527] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/14/2017] [Accepted: 12/18/2017] [Indexed: 12/22/2022] Open
Abstract
Objective Purkinje neuron dysfunction is associated with cerebellar ataxia. In a mouse model of spinocerebellar ataxia type 1 (SCA1), reduced potassium channel function contributes to altered membrane excitability resulting in impaired Purkinje neuron spiking. We sought to determine the relationship between altered membrane excitability and motor dysfunction in SCA1 mice. Methods Patch-clamp recordings in acute cerebellar slices and motor phenotype testing were used to identify pharmacologic agents which improve Purkinje neuron physiology and motor performance in SCA1 mice. Additionally, we retrospectively reviewed records of patients with SCA1 and other autosomal-dominant SCAs with prominent Purkinje neuron involvement to determine whether currently approved potassium channel activators were tolerated. Results Activating calcium-activated and subthreshold-activated potassium channels improved Purkinje neuron spiking impairment in SCA1 mice (P < 0.05). Additionally, dendritic hyperexcitability was improved by activating subthreshold-activated potassium channels but not calcium-activated potassium channels (P < 0.01). Improving spiking and dendritic hyperexcitability through a combination of chlorzoxazone and baclofen produced sustained improvements in motor dysfunction in SCA1 mice (P < 0.01). Retrospective review of SCA patient records suggests that co-treatment with chlorzoxazone and baclofen is tolerated. Interpretation Targeting both altered spiking and dendritic membrane excitability is associated with sustained improvements in motor performance in SCA1 mice, while targeting altered spiking alone produces only short-term improvements in motor dysfunction. Potassium channel activators currently in clinical use are well tolerated and may provide benefit in SCA patients. Future clinical trials with potassium channel activators are warranted in cerebellar ataxia.
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Affiliation(s)
- David D Bushart
- Department of Molecular & Integrative Physiology University of Michigan Ann Arbor Michigan
| | - Ravi Chopra
- Department of Neurology University of Michigan Ann Arbor Michigan
| | - Vikrant Singh
- Department of Pharmacology University of California Davis California
| | - Geoffrey G Murphy
- Department of Molecular & Integrative Physiology University of Michigan Ann Arbor Michigan.,Molecular & Behavioral Neuroscience Institute University of Michigan Ann Arbor Michigan
| | - Heike Wulff
- Department of Pharmacology University of California Davis California
| | - Vikram G Shakkottai
- Department of Molecular & Integrative Physiology University of Michigan Ann Arbor Michigan.,Department of Neurology University of Michigan Ann Arbor Michigan
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6
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Ferrer I. Sisyphus in Neverland. J Alzheimers Dis 2018; 62:1023-1047. [PMID: 29154280 PMCID: PMC5870014 DOI: 10.3233/jad-170609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2017] [Indexed: 11/24/2022]
Abstract
The study of life and living organisms and the way in which these interact and organize to form social communities have been central to my career. I have been fascinated by biology, neurology, and neuropathology, but also by history, sociology, and art. Certain current historical, political, and social events, some occurring proximally but others affecting people in apparently distant places, have had an impact on me. Epicurus, Seneca, and Camus shared their philosophical positions which I learned from. Many scientists from various disciplines have been exciting sources of knowledge as well. I have created a world of hypothesis and experiments but I have also got carried away by serendipity following unexpected observations. It has not been an easy path; errors and wanderings are not uncommon, and opponents close to home much more abundant than one might imagine. Ambition, imagination, resilience, and endurance have been useful in moving ahead in response to setbacks. In the end, I have enjoyed my dedication to science and I am grateful to have glimpsed beauty in it. These are brief memories of a Spanish neuropathologist born and raised in Barcelona, EU.
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Affiliation(s)
- Isidro Ferrer
- Department of Pathology and Experimental Therapeutics, University of Barcelona; Service of Pathological Anatomy, Bellvitge University Hospital; CIBERNED; Hospitalet de Llobregat, Barcelona, Spain
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Neuronal Atrophy Early in Degenerative Ataxia Is a Compensatory Mechanism to Regulate Membrane Excitability. J Neurosci 2015; 35:11292-307. [PMID: 26269637 DOI: 10.1523/jneurosci.1357-15.2015] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Neuronal atrophy in neurodegenerative diseases is commonly viewed as an early event in a continuum that ultimately results in neuronal loss. In a mouse model of the polyglutamine disorder spinocerebellar ataxia type 1 (SCA1), we tested the hypothesis that cerebellar Purkinje neuron atrophy serves an adaptive role rather than being simply a nonspecific response to injury. In acute cerebellar slices from SCA1 mice, we find that Purkinje neuron pacemaker firing is initially normal but, with the onset of motor dysfunction, becomes disrupted, accompanied by abnormal depolarization. Remarkably, subsequent Purkinje cell atrophy is associated with a restoration of pacemaker firing. The early inability of Purkinje neurons to support repetitive spiking is due to unopposed calcium currents resulting from a reduction in large-conductance calcium-activated potassium (BK) and subthreshold-activated potassium channels. The subsequent restoration of SCA1 Purkinje neuron firing correlates with the recovery of the density of these potassium channels that accompanies cell atrophy. Supporting a critical role for BK channels, viral-mediated increases in BK channel expression in SCA1 Purkinje neurons improves motor dysfunction and partially restores Purkinje neuron morphology. Cerebellar perfusion of flufenamic acid, an agent that restores the depolarized membrane potential of SCA1 Purkinje neurons by activating potassium channels, prevents Purkinje neuron dendritic atrophy. These results suggest that Purkinje neuron dendritic remodeling in ataxia is an adaptive response to increases in intrinsic membrane excitability. Similar adaptive remodeling could apply to other vulnerable neuronal populations in neurodegenerative disease. SIGNIFICANCE STATEMENT In neurodegenerative disease, neuronal atrophy has long been assumed to be an early nonspecific event preceding neuronal loss. However, in a mouse model of spinocerebellar ataxia type 1 (SCA1), we identify a previously unappreciated compensatory role for neuronal shrinkage. Purkinje neuron firing in these mice is initially normal, but is followed by abnormal membrane depolarization resulting from a reduction in potassium channels. Subsequently, these electrophysiological effects are counteracted by cell atrophy, which by restoring normal potassium channel membrane density, re-establishes pacemaker firing. Reversing the initial membrane depolarization improved motor function and Purkinje neuron morphology in the SCA1 mice. These results suggest that Purkinje neuron remodeling in ataxia is an active compensatory response that serves to normalize intrinsic membrane excitability.
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8
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Lesion-induced and activity-dependent structural plasticity of Purkinje cell dendritic spines in cerebellar vermis and hemisphere. Brain Struct Funct 2015; 221:3405-26. [PMID: 26420278 DOI: 10.1007/s00429-015-1109-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 09/09/2015] [Indexed: 10/23/2022]
Abstract
Neuroplasticity allows the brain to encode experience and learn behaviors, and also to re-acquire lost functions after damage. The cerebellum is a suitable structure to address this topic because of its strong involvement in learning processes and compensation of lesion-induced deficits. This study was aimed to characterize the effects of a hemicerebellectomy (HCb) combined or not with the exposition to environmental enrichment (EE) on dendritic spine density and size in Purkinje cell proximal and distal compartments of cerebellar vermian and hemispherical regions. Male Wistar rats were housed in enriched or standard environments from the 21st post-natal day (pnd) onwards. At the 75th pnd, rats were submitted to HCb or sham lesion. Neurological symptoms and spatial performance in the Morris water maze were evaluated. At the end of testing, morphological analyses assessed dendritic spine density, area, length, and head diameter on vermian and hemispherical Purkinje cells. All hemicerebellectomized (HCbed) rats showed motor compensation, but standard-reared HCbed animals exhibited cognitive impairment that was almost completely compensated in enriched HCbed rats. The standard-reared HCbed rats showed decreased density with augmented size of Purkinje cell spines in the vermis, and augmented both density and size in the hemisphere. Enriched HCbed rats almost completely maintained the spine density and size induced by EE. Both lesion-induced and activity-dependent cerebellar plastic changes may be interpreted as "beneficial" brain reactions, aimed to support behavioral performance rescuing.
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9
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Animal Models of Spinocerebellar Ataxia Type 1. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00063-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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10
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Chopra R, Shakkottai VG. The role for alterations in neuronal activity in the pathogenesis of polyglutamine repeat disorders. Neurotherapeutics 2014; 11:751-63. [PMID: 24986674 PMCID: PMC4391381 DOI: 10.1007/s13311-014-0289-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Polyglutamine diseases are a class of neurodegenerative diseases that share an expansion of a glutamine-encoding CAG tract in the respective disease genes as a central hallmark. In all of these diseases there is progressive degeneration in a select subset of neurons, and the mechanisms behind this degeneration remain unclear. Emerging evidence from animal models of disease has identified abnormalities in synaptic signaling and intrinsic excitability in affected neurons, which coincide with the onset of symptoms and precede apparent neuropathology. The appearance of these early changes suggests that altered neuronal activity might be an important component of network dysfunction and that these alterations in network physiology could contribute to symptoms of disease. Here we review abnormalities in neuronal function that have been identified in both animal models and patients, and highlight ways in which these changes in neuronal activity may contribute to disease symptoms. We then review the literature supporting an emerging role for abnormalities in neuronal activity as a driver of neurodegeneration. Finally, we identify common themes that emerge from studies of neuronal dysfunction in polyglutamine disease.
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Affiliation(s)
- Ravi Chopra
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 USA
| | - Vikram G. Shakkottai
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 USA
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11
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De Bartolo P, Florenzano F, Burello L, Gelfo F, Petrosini L. Activity-dependent structural plasticity of Purkinje cell spines in cerebellar vermis and hemisphere. Brain Struct Funct 2014; 220:2895-904. [DOI: 10.1007/s00429-014-0833-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 06/24/2014] [Indexed: 12/01/2022]
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12
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Dimitrova M, Petrova E, Gluhcheva Y, Kadiysky D, Dimitrova S, Kolyovska V, Deleva D. Neurodegenerative changes in rat produced by lithium treatment. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2013; 76:304-310. [PMID: 23514072 DOI: 10.1080/15287394.2013.757268] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Lithium is extensively used in psychiatric practice for the prevention and treatment of manic-depressive disorders. However, neurotoxicity attributed to lithium salts within therapeutic doses was also reported in patients, manifested by transient or persistent neurological deficits. In this study, morphological changes were examined in rats treated acutely and chronically with lithium. Pathological changes were observed in different brain regions including cerebral cortex, cerebellum, medulla oblongata, mesencephalon, thalamus, and pons, using a silver-copper impregnation technique for neurodegeneration. Vacuolization of brain tissue with subsequent formation of spongiosis was the prominent morphological feature following lithium administration. The zones of spongiosis were irregularly distributed throughout the brain. More intensive compact areas with spongiform changes were found in the cerebral cortex and medulla oblongata. Less pronounced vacuolization was noted in the pons and thalamic region. The cerebellum and mesencephalon appeared least affected. Vacuolization in the cerebellar cortex was found at loci with Purkinje cells, but the classical picture of spongiosis was not apparent. Data indicate that both acute and chronic lithium intoxication accelerated neurodegenerative changes normally seen with normal brain aging.
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Affiliation(s)
- Mashenka Dimitrova
- Department of Experimental Morphology, Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 25, Sofia, 1113, Bulgaria
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13
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Matilla-Dueñas A, Goold R, Giunti P. Clinical, genetic, molecular, and pathophysiological insights into spinocerebellar ataxia type 1. THE CEREBELLUM 2008; 7:106-14. [DOI: 10.1007/s12311-008-0009-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Abstract
Expansions of CAG trinucleotide repeats encoding glutamine have been found to be the causative mutations of seven human neurodegenerative diseases. Similarities in the clinical, genetic, and molecular features of these disorders suggest they share a common mechanism of pathogenesis. Recent progress in the generation and characterization of transgenic mice expressing the genes containing expanded repeats associated with spinal and bulbar muscular atrophy (SBMA), spinocerebellar ataxia type 1 (SCA1), Machado-Joseph disease (MJD/SCA3), and Huntington's disease (HD) is beginning to provide insight into the underlying mechanisms of these neurodegenerative disorders.
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Affiliation(s)
- E N Burright
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55455, USA.
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15
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Orr HT. Spinocerebellar Ataxia Type 1. Neurobiol Dis 2007. [DOI: 10.1016/b978-012088592-3/50015-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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16
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Ramio-Torrentia L, Gomez E, Genis D. Swallowing in degenerative ataxias. J Neurol 2006; 253:875-81. [PMID: 16619126 DOI: 10.1007/s00415-006-0122-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Revised: 12/20/2005] [Accepted: 12/22/2005] [Indexed: 01/12/2023]
Affiliation(s)
- L Ramio-Torrentia
- Section of Neurology, Hospital Universitari de Girona, Dr Josep Trueta, Avda de Franca s/n, 17007, Girona, Spain
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Aronica E, van Kempen AAMW, van der Heide M, Poll-The BT, van Slooten HJ, Troost D, Rozemuller-Kwakkel JM. Congenital disorder of glycosylation type Ia: a clinicopathological report of a newborn infant with cerebellar pathology. Acta Neuropathol 2005; 109:433-42. [PMID: 15714316 DOI: 10.1007/s00401-004-0975-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 12/06/2004] [Accepted: 12/06/2004] [Indexed: 12/11/2022]
Abstract
Congenital disorders of glycosylation (CDG) represent a newly delineated group of inherited multisystem disorders characterized by defective glycoprotein biosynthesis. In the present study we report and discuss the clinical and neuropathological findings in a newborn with CDG type Ia (CDG-Ia). The patient presented mild dysmorphic facial features, inverted nipples, progressive generalized edema, hypertrophic cardiomyopathy, hepatosplenomegaly, muscular hypotonia and had severe hypoalbuminemia. Deficiency of phosphomannomutase (PMM)-2 activity was detected. Molecular analysis showed V231M/T237R mutations of the PMM2 gene. Muscular biopsy, disclosed myopathic alterations with myofibrillar disarray by electron microscopy. The patient died at 1 month of age of circulatory and respiratory failure. Autopsy showed liver fibrosis and renal abnormalities. Neuropathological abnormalities were mainly confined to the cerebellum. Histological and immunocytochemical examination of cerebellar tissue showed partial atrophy of cerebellar folia with severe loss of Purkinje cells, granular cell depletion and various morphological changes in the remaining Purkinje cells and their dendritic arborization. Autopsy findings confirm the complexity of the CDG-Ia syndrome, and indicate that CDG-Ia is a distinct disease entity, which can be differentiated from other neurological disorders and other types of CDG, not only clinically, but also based on unique pathological findings. The data proved useful in determining the underlying disease process associated with a defective N-glycosylation pathway.
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Affiliation(s)
- E Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ , Amsterdam, The Netherlands,
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18
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van Rootselaar AF, Aronica E, Jansen Steur ENH, Rozemuller-Kwakkel JM, de Vos RAI, Tijssen MAJ. Familial cortical tremor with epilepsy and cerebellar pathological findings. Mov Disord 2004; 19:213-7. [PMID: 14978679 DOI: 10.1002/mds.10662] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The clinical and neuropathological findings in a patient with familial cortical tremor with epilepsy (FCTE) are described. Clinically, the patient showed cortical myoclonus, tremor, and generalized seizures. Pathological investigation showed cerebellar degeneration and somal sprouting and loss of dendritic tree in Purkinje cells. Striking similarities were found in diseases caused by channelopathies such as spinocerebellar ataxia subtype 6.
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Abstract
Spines are neuronal protrusions, each of which receives input typically from one excitatory synapse. They contain neurotransmitter receptors, organelles, and signaling systems essential for synaptic function and plasticity. Numerous brain disorders are associated with abnormal dendritic spines. Spine formation, plasticity, and maintenance depend on synaptic activity and can be modulated by sensory experience. Studies of compartmentalization have shown that spines serve primarily as biochemical, rather than electrical, compartments. In particular, recent work has highlighted that spines are highly specialized compartments for rapid large-amplitude Ca(2+) signals underlying the induction of synaptic plasticity.
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Affiliation(s)
- Esther A Nimchinsky
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA.
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20
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Fusco FR, Viscomi MT, Bernardi G, Molinari M. Localization of ataxin-2 within the cerebellar cortex of the rat. Brain Res Bull 2001; 56:343-7. [PMID: 11719270 DOI: 10.1016/s0361-9230(01)00601-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Spinocerebellar ataxia type 2 is caused by a polyglutamine stretch in the protein ataxin-2 that is due to an expansion of a CAG repeat in the spinocerebellar ataxia-2 gene. The function of wild-type ataxin-2 has not been clarified. A widespread distribution of this protein throughout the brain has been reported. We examined the expression of ataxin-2 in cortical cerebellar cells of the adult rat. We performed a single label immunohistochemical study of ataxin-2 and a single label immunofluorescence study of ataxin-2 and zebrin on adjacent sections, to compare the distribution of the observed parasagittal band pattern. We also performed a double label immunofluorescence study of ataxin-2 and one of each parvalbumin, calbindin, and calretinin. Single label studies revealed that between 50% and 70% of the Purkinje cells express ataxin-2. The abundance of ataxin-2 was different between hemisphere and vermis, with a clear prevalence for the former. Furthermore, the distribution of ataxin-2-positive Purkinje cells showed a peculiar alternating parasagittal band pattern. Among the other cortical cerebellar cells only basket and granule cells showed ataxin-2 staining. Our dual label studies showed that about 50% of calbindin and more than 70% of parvalbumin-immunoreactive Purkinje cells were also labeled for ataxin-2. The uneven distribution of ataxin-2 expression in the Purkinje cell layer does not support the hypothesized link between ataxin-2 content and cell vulnerability. The differences in ataxin-2 expression among the cell types of cerebellar cortex, on the other hand, suggest a possible correlation between ataxin-2 content and cell function.
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Affiliation(s)
- F R Fusco
- Laboratory of Experimental Neurorehabilitation, Santa Lucia Foundation I.R.C.C.S., Rome, Italy.
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21
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Orr HT. The ins and outs of a polyglutamine neurodegenerative disease: spinocerebellar ataxia type 1 (SCA1). Neurobiol Dis 2000; 7:129-34. [PMID: 10860780 DOI: 10.1006/nbdi.2000.0305] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polyglutamine neurodegenerative disorders are characterized by the expansion of a glutamine tract within the mutant disease-causing protein. Expression of the mutant protein induces a progressive loss of neuronal function and the subsequent neurodegeneration of a set of neurons characteristic to each disease. Spinocerebellar ataxia type 1 (SCA1) is one polyglutamine disease where various experimental model systems, in particular transgenic mice, have been utilized to dissect the molecular and cellular events important for disease. This review summarizes these findings and places them in a context of potential future research directions.
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Affiliation(s)
- H T Orr
- Department of Genetics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.
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22
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Clark HB, Orr HT. Spinocerebellar ataxia type 1--modeling the pathogenesis of a polyglutamine neurodegenerative disorder in transgenic mice. J Neuropathol Exp Neurol 2000; 59:265-70. [PMID: 10759181 DOI: 10.1093/jnen/59.4.265] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is one of a group of dominantly inherited neurodegenerative diseases caused by a mutant expansion of a polyglutamine-repeated sequence within the affected gene. One of the major cell types affected by the gene (ataxin-1) mutation in SCA1 is the cerebellar Purkinje cell. Targeted expression of mutant ataxin-1 in Purkinje cells of transgenic mice produces an ataxic phenotype with pathological similarities to the human disease. Other transgenic experiments using altered forms of mutant ataxin-1 have shown that nuclear localization of the mutant protein is necessary for pathogenesis and that nuclear aggregates of ubiquitinated mutant protein, while a feature of SCA1 and other polyglutamine diseases, are not a requirement for pathogenesis in transgenic models of SCA1. Present and future generations of transgenic mouse models of SCA1 will be valuable tools to further address mechanisms of pathogenesis in polyglutamine-related disorders.
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Affiliation(s)
- H B Clark
- Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis 55455, USA
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23
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Gilman S, Koeppe RA, Junck L, Little R, Kluin KJ, Heumann M, Martorello S, Johanns J. Decreased striatal monoaminergic terminals in multiple system atrophy detected with positron emission tomography. Ann Neurol 1999; 45:769-77. [PMID: 10360769 DOI: 10.1002/1531-8249(199906)45:6<769::aid-ana11>3.0.co;2-g] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We examined the density of striatal presynaptic monoaminergic terminals, using a ligand for the type 2 vesicular monoamine transporter, (+)-[11C]dihydrotetrabenazine, with positron emission tomography in 7 normal control subjects, 8 multiple system atrophy (MSA) patients with predominantly parkinsonian features (MSA-P), 8 MSA patients with principally cerebellar dysfunction (MSA-C), and 6 sporadic olivopontocerebellar atrophy (sOPCA) patients. The findings were correlated with the results of neurological evaluations and magnetic resonance imaging studies. Specific binding was significantly reduced in the putamen of all patient groups in the order MSA-P < MSA-C < sOPCA, compared with controls. Mean blood-to-brain ligand transport (K1) was significantly decreased in the putamen of all patient groups and in the cerebellar hemispheres of MSA-C and sOPCA but not MSA-P groups, compared with controls. Significant negative correlations were found between striatal binding and the intensity of parkinsonian features and between cerebellar K1 and the intensity of cerebellar dysfunction. The results suggest fundamental differences between MSA-P and MSA-C groups reflecting differential severity of degeneration of nigrostriatal and cerebellar systems in these two forms of MSA. The findings also show that some sOPCA patients have subclinical nigrostriatal dysfunction and are at risk of developing MSA with disease progression.
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Affiliation(s)
- S Gilman
- Department of Neurology, University of Michigan, Ann Arbor 48109-0316, USA
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24
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Purkinje cell expression of a mutant allele of SCA1 in transgenic mice leads to disparate effects on motor behaviors, followed by a progressive cerebellar dysfunction and histological alterations. J Neurosci 1997. [PMID: 9295384 DOI: 10.1523/jneurosci.17-19-07385.1997] [Citation(s) in RCA: 178] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurological disorder caused by the expansion of a CAG repeat encoding a polyglutamine tract. Work presented here describes the behavioral and neuropathological course seen in mutant SCA1 transgenic mice. Behavioral tests indicate that at 5 weeks of age mutant mice have an impaired performance on the rotating rod in the absence of deficits in balance and coordination. In contrast, these mutant SCA1 mice have an increased initial exploratory behavior. Thus, expression of the mutant SCA1 allele within cerebellar Purkinje cells has divergent effects on the motor behavior of juvenile animals: a compromise of rotating rod performance and a simultaneous enhancement of initial exploratory activity. With age, these animals develop incoordination with concomitant progressive Purkinje neuron dendritic and somatic atrophy but relatively little cell loss. Therefore, the eventual development of ataxia caused by the expression of a mutant SCA1 allele is not the result of cell death per se, but the result of cellular dysfunction and morphological alterations that occur before neuronal demise.
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25
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Selective degeneration fo Purkinje cells with Lewy body-like inclusions in aged NFHLACZ transgenic mice. J Neurosci 1997. [PMID: 8994061 DOI: 10.1523/jneurosci.17-03-01064.1997] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Transgenic (NFHLacZ) mice expressing a fusion protein composed of a truncated high-molecular-weight mouse neurofilament (NF) protein (NFH) fused to beta-galactosidase (LacZ) develop inclusions in neurons throughout the CNS. These inclusions persist from birth to advanced age and contain massive filamentous aggregates including all three endogenous NF proteins and the NFHLacZ fusion protein. Further, the levels of endogenous NF proteins are selectively reduced in NFHLacZ mice. Because these inclusions resemble NF-rich Lewy bodies (LBs) in Parkinson's disease and LB dementia, we asked whether these lesions compromised the viability of affected neurons during aging. We studied hippocampal CA1 neurons, nearly all of which harbored inclusions (type I) devoid of cellular organelles, and cerebellar Purkinje cells, nearly all of which accumulated inclusions (type II) containing numerous entrapped organelles. Purkinje cells with type II inclusions began to degenerate in the NFHLacZ mice at approximately 1 year of age, and most were eliminated by 18 months of age. In contrast, there was no significant loss of type I inclusion-bearing CA1 neurons with age. These data suggest that the sequestration of cellular organelles in type II inclusions may isolate and impair the function of these organelles, thereby rendering Purkinje cells selectively vulnerable to degeneration with age as in neurodegenerative diseases of the elderly characterized by accumulation of LBs.
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Gilman S, Frey KA, Koeppe RA, Junck L, Little R, Vander Borght TM, Lohman M, Martorello S, Lee LC, Jewett DM, Kilbourn MR. Decreased striatal monoaminergic terminals in olivopontocerebellar atrophy and multiple system atrophy demonstrated with positron emission tomography. Ann Neurol 1996; 40:885-92. [PMID: 9007093 DOI: 10.1002/ana.410400610] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We used [11C]dihydrotetrabenazine, a new ligand for the type 2 vesicular monoamine transporter (VMAT2), with positron emission tomography to study striatal monoaminergic presynaptic terminals in 4 patients with multiple system atrophy, 8 with sporadic olivopontocerebellar atrophy, and 9 normal control subjects. Specific binding in the striatum was significantly reduced in the multiple system atrophy patients as compared with the normal control group, with average reductions of 61% in the caudate nucleus (p = 0.002) and 58% in the putamen (p = 0.009). Smaller reductions were found in the sporadic olivopontocerebellar atrophy group, averaging 26% in the caudate nucleus (p = 0.05) and 24% in the putamen (p = 0.11). Mean blood-to-brain [11C]dihydrotetrabenazine transport (K1) was significantly different between groups only in the cerebellum, with values for the sporadic olivopontocerebellar atrophy group diminished compared with the normal control group. Cerebellar K1 was not significantly decreased in the multiple system atrophy group. The finding of reduced striatal VMAT2 in sporadic olivopontocerebellar atrophy patients suggests nigrostriatal pathology, indicating that some may later develop symptomatic extrapyramidal disease.
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Affiliation(s)
- S Gilman
- Department of Neurology, University of Michigan, Ann Arbor 48109-0316, USA
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27
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Berciano J, Ferrer I. Glial and neuronal cytoplasmic inclusions in familial olivopontocerebellar atrophy. Ann Neurol 1996; 40:819-20. [PMID: 8957028 DOI: 10.1002/ana.410400524] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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28
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Gilman S, Koeppe RA, Junck L, Kluin KJ, Lohman M, St Laurent RT. Benzodiazepine receptor binding in cerebellar degenerations studied with positron emission tomography. Ann Neurol 1995; 38:176-85. [PMID: 7654065 DOI: 10.1002/ana.410380209] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We used positron emission tomography with [11C]flumazenil to study gamma-aminobutyric acid type A/benzodiazepine receptor binding quantitatively in the cerebral hemispheres, basal ganglia, thalamus, cerebellum, and brainstem of 72 subjects, including 14 with multiple system atrophy of the ataxic (olivopontocerebellar atrophy) type, 5 with multiple system atrophy of the extrapyramidal/autonomic (Shy-Drager syndrome) type, 18 with sporadic olivopontocerebellar atrophy, 15 with dominantly inherited olivopontocerebellar atrophy, and 20 normal control subjects with similar age and sex distributions. In comparison with data obtained from the normal control subjects, we found significantly decreased ligand influx in the cerebellum and brainstem of multiple system atrophy patients of the olivopontocerebellar atrophy type and in patients with sporadic olivopontocerebellar atrophy, but not in patients with multiple system atrophy of the Shy-Drager syndrome type. Despite these differences in ligand influx, benzodiazepine binding was largely preserved in the cerebral hemispheres, basal ganglia, thalamus, cerebellum, and brainstem in patients with multiple system atrophy of both types as well as those with sporadic or dominantly inherited olivopontocerebellar atrophy as compared with normal control subjects. The finding of relative preservation of benzodiazepine receptors indicates that these sites are available for pharmacological therapy in these disorders.
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Affiliation(s)
- S Gilman
- Department of Neurology, University of Michigan, Ann Arbor, USA
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29
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Genis D, Matilla T, Volpini V, Rosell J, Dávalos A, Ferrer I, Molins A, Estivill X. Clinical, neuropathologic, and genetic studies of a large spinocerebellar ataxia type 1 (SCA1) kindred: (CAG)n expansion and early premonitory signs and symptoms. Neurology 1995; 45:24-30. [PMID: 7824128 DOI: 10.1212/wnl.45.1.24] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We report the clinical, neuropathologic, and genetic studies of a large kindred (family M-ADCA1) with autosomal dominant spinocerebellar ataxia type 1 (SCA1), ascertained in 41 members, with clinical data available in twenty-two. The mean age of onset was 36.3 +/- 6.2 years (ages, 26 to 52), the mean duration of the disease was 15.8 +/- 6.5 years (range, 10 to 28 years), and the mean age at death was 54.1 +/- 9.5 years (ages, 39 to 72). Premonitory signs and symptoms appeared earlier than the usual onset symptoms in many of the clinically unaffected patients who inherited the mutated SCA1 gene. Anticipation was present when we compared the seventh and eighth generations. A more severe course of the disease occurred in offspring of affected males. Neuropathologic examination, performed on three patients, showed the usual findings of SCA1; Golgi and immunocytochemistry studies suggested primary damage of the Purkinje cells. We analyzed the CAG-repeat mutation responsible for the SCA1 phenotype in a total of 41 family members. There was expansion in 19 subjects (10 clinically affected, seven with early signs and symptoms, and two asymptomatic individuals), and all showed heterozygosity, with one allele between 41 and 59 repeats (SCA1 mutation) and the other in the range of 6 to 39 repeats (normal range). The clinical analysis of "at risk" patients with the SCA1 mutation showed that minor signs and symptoms begin before full clinical diagnosis, and these premonitory manifestations can herald full development of SCA1 by years.
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Affiliation(s)
- D Genis
- Neurologic Unit, Hospital de Girona, Dr. Josep Trueta, Spain
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