Caspar, an adapter for VAP and TER94, delays the progression of disease by regulating glial inflammation in a Drosophila model of ALS8

Amyotrophic Lateral Sclerosis (ALS) is a fatal, late-onset, progressive motor neurodegenerative disorder. We have been studying cellular and molecular mechanisms involved in ALS using a vesicle-associated membrane protein-associated protein B (VAPB/ALS8) Drosophila model, which mimics many systemic aspects of the human disease. Here, we show that the ER-resident VAPB interacts with Caspar, an ortholog of human fas associated factor 1 (FAF1). Caspar, in turn, interacts with transitional endoplasmic reticulum ATPase (TER94), a fly ortholog of ALS14 (VCP/p97, Valosin-containing protein), via its UBX domain and poly-ubiquitinated proteins with its UBA domain. Caspar overexpression in the glia extends lifespan and also slows the progression of motor dysfunction in the ALS8 model, a phenomenon that we ascribe to its ability to restrain age-dependant inflammation, modulated by Relish/NFBκ signaling. We hypothesize that Caspar is a key molecule in the pathogenesis of ALS. Caspar connects the plasma membrane (PM) localized immune signalosome to the ER-based VAPB degradative machinery, presumably at PM:ER contact sites. The Caspar:TER94:VAPB complex appears to be a strong candidate for regulating both protein homeostasis and NFκ signaling. These, in turn, regulate glial inflammation and determine the progression of the disease. Our study projects human FAF1 as an important protein target to alleviate the progression of motor neuron disease.

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Neuronal over-expression of Oxr1 is protective against ALS-associated mutant TDP-43 mislocalisation in motor neurons and neuromuscular defects in vivo

Human Molecular Genetics ◽

10.1093/hmg/ddz190 ◽

2019 ◽

Vol 28 (21) ◽

pp. 3584-3599 ◽

Cited By ~ 4

Author(s):

Matthew G Williamson ◽

Mattéa J Finelli ◽

James N Sleigh ◽

Amy Reddington ◽

David Gordon ◽

...

Keyword(s):

Motor Neurons ◽

Neurodegenerative Disorder ◽

Late Onset ◽

Gene Encoding ◽

Over Expression ◽

Neuromuscular Abnormalities ◽

And Function ◽

Lateral Sclerosis

Abstract A common pathological hallmark of amyotrophic lateral sclerosis (ALS) and the related neurodegenerative disorder frontotemporal dementia, is the cellular mislocalization of transactive response DNA-binding protein 43 kDa (TDP-43). Additionally, multiple mutations in the TARDBP gene (encoding TDP-43) are associated with familial forms of ALS. While the exact role for TDP-43 in the onset and progression of ALS remains unclear, the identification of factors that can prevent aberrant TDP-43 localization and function could be clinically beneficial. Previously, we discovered that the oxidation resistance 1 (Oxr1) protein could alleviate cellular mislocalization phenotypes associated with TDP-43 mutations, and that over-expression of Oxr1 was able to delay neuromuscular abnormalities in the hSOD1G93A ALS mouse model. Here, to determine whether Oxr1 can protect against TDP-43-associated phenotypes in vitro and in vivo, we used the same genetic approach in a newly described transgenic mouse expressing the human TDP-43 locus harbouring an ALS disease mutation (TDP-43M337V). We show in primary motor neurons from TDP-43M337V mice that genetically-driven Oxr1 over-expression significantly alleviates cytoplasmic mislocalization of mutant TDP-43. We also further quantified newly-identified, late-onset neuromuscular phenotypes of this mutant line, and demonstrate that neuronal Oxr1 over-expression causes a significant reduction in muscle denervation and neuromuscular junction degeneration in homozygous mutants in parallel with improved motor function and a reduction in neuroinflammation. Together these data support the application of Oxr1 as a viable and safe modifier of TDP-43-associated ALS phenotypes.

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A streamlined CRISPR workflow to introduce mutations and generate isogenic iPSCs for modeling amyotrophic lateral sclerosis

10.1101/2021.06.21.449257 ◽

2021 ◽

Author(s):

Eric Deneault ◽

Mathilde Chaineau ◽

Maria Jose Castellanos-Montiel ◽

Anna Kristyna Franco Flores ◽

Ghazal Haghi ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Motor Neurons ◽

Molecular Mechanisms ◽

Neurodegenerative Disorder ◽

Control Line ◽

Human Neurons ◽

Recent Developments ◽

Induced Pluripotent ◽

Specific Contribution ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) represents a complex neurodegenerative disorder with significant genetic heterogeneity. To date, both the genetic etiology and the underlying molecular mechanisms driving this disease remain poorly understood, although in recent years a number of studies have highlighted a number of genetic mutations causative for ALS. With these mutations pointing to potential pathways that may be affected within individuals with ALS, having the ability to generate human neurons and other disease relevant cells containing these mutations becomes even more critical if new therapies are to emerge. Recent developments with the advent of induced pluripotent stem cells (iPSCs) and clustered regularly interspaced short palindromic repeats (CRISPR) gene editing fields gave us the tools to introduce or correct a specific mutation at any site within the genome of an iPSC, and thus model the specific contribution of risk mutations. In this study we describe a rapid and efficient way to either introduce a mutation into a control line, or to correct a mutation, generating an isogenic control line from patient-derived iPSCs with a given mutation. The mutations introduced were the G93A mutation into SOD1 or H517Q into FUS, and the mutation corrected was a patient iPSC line with I114T in SOD1. A combination of small molecules and growth factors were used to guide a stepwise differentiation of the edited cells into motor neurons in order to demonstrate that disease-relevant cells could be generated for downstream applications. Through a combination of iPSCs and CRISPR editing, the cells generated here will provide fundamental insights into the molecular mechanisms underlying neuron degeneration in ALS.

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Presynaptic dysfunction in Huntington's disease

Biochemical Society Transactions ◽

10.1042/bst0380488 ◽

2010 ◽

Vol 38 (2) ◽

pp. 488-492 ◽

Cited By ~ 16

Author(s):

José L. Rozas ◽

Leonardo Gómez-Sánchez ◽

Cristina Tomás-Zapico ◽

José J. Lucas ◽

Rafael Fernández-Chacón

Keyword(s):

Huntington's Disease ◽

Huntington’S Disease ◽

Molecular Mechanisms ◽

Neuronal Damage ◽

Motor Dysfunction ◽

Drosophila Model ◽

Glutamine Repeat ◽

Mutant Forms ◽

The Relationship

HD (Huntington's disease) is produced by the expression of mutant forms of the protein htt (huntingtin) containing a pathologically expanded poly-glutamine repeat. For unknown reasons, in HD patients and HD mouse models, neurons from the striatum and cerebral cortex degenerate and lead to motor dysfunction and dementia. Synaptic transmission in those neurons becomes progressively altered during the course of the disease. However, the relationship between synaptic dysfunction and neurodegeneration in HD is not yet clear. Are there early specific functional synaptic changes preceding symptoms and neurodegeneration? What is the role of those changes in neuronal damage? Recent experiments in a Drosophila model of HD have showed that abnormally increased neurotransmitter release might be a leading cause of neurodegeneration. In the present review, we summarize recently described synaptic alterations in HD animal models and discuss potential underlying molecular mechanisms.

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Immune Signaling Kinases in Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD)

International Journal of Molecular Sciences ◽

10.3390/ijms222413280 ◽

2021 ◽

Vol 22 (24) ◽

pp. 13280

Author(s):

Raquel García-García ◽

Laura Martín-Herrero ◽

Laura Blanca-Pariente ◽

Jesús Pérez-Cabello ◽

Cintia Roodveldt

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Frontotemporal Dementia ◽

Motor Neurons ◽

Molecular Mechanisms ◽

Neurodegenerative Disorder ◽

Therapeutic Potential ◽

Neuronal Loss ◽

Immune Signaling ◽

Health And Disease ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disorder of motor neurons in adults, with a median survival of 3–5 years after appearance of symptoms, and with no curative treatment currently available. Frontotemporal dementia (FTD) is also an adult-onset neurodegenerative disease, displaying not only clinical overlap with ALS, but also significant similarities at genetic and pathologic levels. Apart from the progressive loss of neurons and the accumulation of protein inclusions in certain cells and tissues, both disorders are characterized by chronic inflammation mediated by activated microglia and astrocytes, with an early and critical impact of neurodegeneration along the disease course. Despite the progress made in the last two decades in our knowledge around these disorders, the underlying molecular mechanisms of such non-cell autonomous neuronal loss still need to be clarified. In particular, immune signaling kinases are currently thought to have a key role in determining the neuroprotective or neurodegenerative nature of the central and peripheral immune states in health and disease. This review provides a comprehensive and updated view of the proposed mechanisms, therapeutic potential, and ongoing clinical trials of immune-related kinases that have been linked to ALS and/or FTD, by covering the more established TBK1, RIPK1/3, RACK I, and EPHA4 kinases, as well as other emerging players in ALS and FTD immune signaling.

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Bidens pilosa Extract Administered after Symptom Onset Attenuates Glial Activation, Improves Motor Performance, and Prolongs Survival in a Mouse Model of Amyotrophic Lateral Sclerosis

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/1020673 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Yasuhiro Kosuge ◽

Erina Kaneko ◽

Hiroshi Nango ◽

Hiroko Miyagishi ◽

Kumiko Ishige ◽

...

Keyword(s):

Spinal Cord ◽

Amyotrophic Lateral Sclerosis ◽

Mouse Model ◽

Motor Neurons ◽

Motor Performance ◽

Neurodegenerative Disorder ◽

Late Onset ◽

Bidens Pilosa ◽

Neuronal Marker ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder characterized by progressive paralysis resulting from the death of upper and lower motor neurons. There is currently no effective pharmacological treatment for ALS, and the two approved drugs riluzole and edaravone have limited effects on the symptoms and only slightly prolong the life of patients. Therefore, the development of effective therapeutic strategies is of paramount importance. In this study, we investigated whether Miyako Island Bidens pilosa (MBP) can alleviate the neurological deterioration observed in a superoxide dismutase-1 G93A mutant transgenic mouse (G93A mouse) model of ALS. We orally administered 2 g/kg/day of MBP to G93A mice at the onset of symptoms of neurodegeneration (15 weeks old) until death. Treatment with MBP markedly prolonged the life of ALS model mice by approximately 20 days compared to that of vehicle-treated ALS model mice and significantly improved motor performance. MBP treatment prevented the reduction in SMI32 expression, a neuronal marker protein, and attenuated astrocyte (detected by GFAP) and microglia (detected by Iba-1) activation in the spinal cord of G93A mice at the end stage of the disease (18 weeks old). Our results indicate that MBP administered after the onset of ALS symptoms suppressed the inflammatory activation of microglia and astrocytes in the spinal cord of the G93A ALS model mice, thus improving their quality of life. MBP may be a potential therapeutic agent for ALS.

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Homozygous SOD1 Variation L144S Produces a Severe Form of Amyotrophic Lateral Sclerosis in an Iranian Family

Neurology Genetics ◽

10.1212/nxg.0000000000000645 ◽

2021 ◽

Vol 8 (1) ◽

pp. e645

Author(s):

Delia Gagliardi ◽

Minoo Ahmadinejad ◽

Roberto Del Bo ◽

Megi Meneri ◽

Giacomo Pietro Comi ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Motor Neurons ◽

Early Onset ◽

Neurodegenerative Disorder ◽

Late Onset ◽

Muscular Atrophy ◽

Severe Form ◽

Iranian Family ◽

Fast Progression ◽

Lateral Sclerosis

ObjectivesAmyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disorder characterized by degeneration of motor neurons determining progressive muscular atrophy, weakness, and death from respiratory failure.MethodsHere, we report clinical and molecular findings of a novel Iranian family affected with a severe form of early-onset familial ALS.ResultsThree siblings born to consanguineous parents developed a form of ALS characterized by early-onset lower limb involvement and a fast progression, proving fatal at age 16 years for 1 of them. Molecular analysis of the SOD1 gene revealed the homozygous substitution c.434T>C in exon 5 resulting in the amino acid change p.Leu144Ser (L144S), previously reported as a dominant variant. Both parents were heterozygous carriers. The probands' mother recently developed a late-onset ALS with predominant upper motor neuron involvement.DiscussionThis report adds p.L144S to the short list of homozygous SOD1 variants and suggests that the development of an earlier-onset and/or faster disease progression can occur when 2 mutated alleles are present.

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Monozygotic twin pairs discordant for amyotrophic lateral sclerosis carry both common and unique epigenetic differences relevant to disease

10.1101/090977 ◽

2016 ◽

Author(s):

Paul E Young ◽

Stephen Kum Jew ◽

Michael E Buckland ◽

Roger Pamphlett ◽

Catherine M Suter

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Large Scale ◽

Cytosine Methylation ◽

Neurodegenerative Disorder ◽

Late Onset ◽

Monozygotic Twin ◽

Sporadic Als ◽

High Heritability ◽

Als Patients ◽

Lateral Sclerosis

AbstractAmyotrophic lateral sclerosis (ALS) is a devastating late-onset neurodegenerative disorder in which only a small proportion of patients carry an identifiable causative genetic lesion. Despite high heritability estimates, a genetic etiology for most sporadic ALS remains elusive. Here we report the epigenetic profiling of five monozygotic twin pairs discordant for ALS in whom previous genome sequencing excluded a genetic basis for their disease discordance. By studying cytosine methylation patterns in peripheral blood DNA we identified thousands of large between-twin differences at individual CpGs. While the specific sites of difference were largely idiosyncratic to a twin pair, a proportion (involving GABA signalling) were common to all affected individuals. In both instances the differences occurred within genes and pathways related to neurobiological function and dysfunction. Our findings reveal widespread changes in epigenetic marks in ALS patients, consistent with an epigenetic contribution to disease. These findings may be exploited to develop blood-based biomarkers of ALS and develop further insight into disease pathogenesis. We expect that our findings will provide a useful point of reference for further large scale studies of sporadic ALS.

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Physiological and pathological functions of LRRK2: implications from substrate proteins

Neuronal Signaling ◽

10.1042/ns20180005 ◽

2018 ◽

Vol 2 (4) ◽

Cited By ~ 4

Author(s):

Miho Araki ◽

Genta Ito ◽

Taisuke Tomita

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Molecular Mechanisms ◽

Kinase Activity ◽

Neurodegenerative Disorder ◽

Lewy Bodies ◽

Motor Dysfunction ◽

Substantia Nigra Pars Compacta ◽

Rab Gtpases ◽

Substrate Proteins

Leucine-rich repeat kinase 2 (LRRK2) encodes a 2527-amino acid (aa) protein composed of multiple functional domains, including a Ras of complex proteins (ROC)-type GTP-binding domain, a carboxyl terminal of ROC (COR) domain, a serine/threonine protein kinase domain, and several repeat domains. LRRK2 is genetically involved in the pathogenesis of both sporadic and familial Parkinson’s disease (FPD). Parkinson’s disease (PD) is the second most common neurodegenerative disorder, manifesting progressive motor dysfunction. PD is pathologically characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta, and the presence of intracellular inclusion bodies called Lewy bodies (LB) in the remaining neurons. As the most frequent PD-causing mutation in LRRK2, G2019S, increases the kinase activity of LRRK2, an abnormal increase in LRRK2 kinase activity is believed to contribute to PD pathology; however, the precise biological functions of LRRK2 involved in PD pathogenesis remain unknown. Although biochemical studies have discovered several substrate proteins of LRRK2 including Rab GTPases and tau, little is known about whether excess phosphorylation of these substrates is the cause of the neurodegeneration in PD. In this review, we summarize latest findings regarding the physiological and pathological functions of LRRK2, and discuss the possible molecular mechanisms of neurodegeneration caused by LRRK2 and its substrates.

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Glycolysis upregulation is neuroprotective as a compensatory mechanism in ALS

eLife ◽

10.7554/elife.45114 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 18

Author(s):

Ernesto Manzo ◽

Ileana Lorenzini ◽

Dianne Barrameda ◽

Abigail G O'Conner ◽

Jordan M Barrows ◽

...

Keyword(s):

Motor Neurons ◽

Glucose Transporter ◽

Neurodegenerative Disorder ◽

Compensatory Mechanism ◽

Vesicle Recycling ◽

Key Indicator ◽

Metabolic Dysregulation ◽

Drosophila Model ◽

Locomotor Deficits ◽

Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS), is a fatal neurodegenerative disorder, with TDP-43 inclusions as a major pathological hallmark. Using a Drosophila model of TDP-43 proteinopathy we found significant alterations in glucose metabolism including increased pyruvate, suggesting that modulating glycolysis may be neuroprotective. Indeed, a high sugar diet improves locomotor and lifespan defects caused by TDP-43 proteinopathy in motor neurons or glia, but not muscle, suggesting that metabolic dysregulation occurs in the nervous system. Overexpressing human glucose transporter GLUT-3 in motor neurons mitigates TDP-43 dependent defects in synaptic vesicle recycling and improves locomotion. Furthermore, PFK mRNA, a key indicator of glycolysis, is upregulated in flies and patient derived iPSC motor neurons with TDP-43 pathology. Surprisingly, PFK overexpression rescues TDP-43 induced locomotor deficits. These findings from multiple ALS models show that mechanistically, glycolysis is upregulated in degenerating motor neurons as a compensatory mechanism and suggest that increased glucose availability is protective.

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PTK2 regulates the UPS impairment via p62 phosphorylation in TDP-43 proteinopathy

10.1101/355446 ◽

2018 ◽

Cited By ~ 2

Author(s):

Shinrye Lee ◽

Yu-Mi Jeon ◽

Seyeon Kim ◽

Younghwi Kwon ◽

Myungjin Jo ◽

...

Keyword(s):

Molecular Mechanisms ◽

Kinase Inhibitor ◽

Critical Role ◽

Neuronal Cells ◽

Ubiquitin Proteasome System ◽

Ubiquitinated Proteins ◽

Phosphorylated Form ◽

Ubiquitin Proteasome ◽

Autophagic Degradation ◽

Lateral Sclerosis

AbstractTDP-43 proteinopathy is a common feature in a variety of neurodegenerative disorders including Amyotrophic lateral sclerosis (ALS) cases, Frontotemporal lobar degeneration (FTLD), and Alzheimer’s disease. However, the molecular mechanisms underlying TDP-43-induced neurotoxicity are largely unknown. In this study, we demonstrated that TDP-43 proteinopathy induces impairment in ubiquitin-proteasome system (UPS) evidenced by an accumulation of ubiquitinated proteins and reduction of proteasome activity in neuronal cells. Through kinase inhibitor screening, we identified PTK2 as a suppressor of neurotoxicity induced by UPS impairment. Importantly, PTK2 inhibition significantly reduces ubiquitin aggregates and attenuated TDP-43-induced cytotoxicity in Drosophila model of TDP-43 proteinopathy. We further identified that phosphorylation of p62 at serine 403 (p-p62S403), a key component in the autophagic degradation of poly-ubiquitinated proteins, is increased upon TDP-43 overexpression and dependent on activation of PTK2 in neuronal cells. Moreover, expressing a non-phosphorylated form of p62 (p62S403A) significantly represses accumulation of polyubiquitinated proteins and neurotoxicity induced by TDP-43 overexpression in neuronal cells. In addition, inhibition of TBK1, a kinase which phosphorylates S403 of p62, ameliorates neurotoxicity upon UPS impairment in neuronal cells. Taken together, our data suggest that activation of PTK2-TBK1-p62 axis plays a critical role in the pathogenesis of TDP-43 by regulating neurotoxicity induced by UPS impairment. Therefore, targeting PTK2-TBK1-p62 axis may represent a novel therapeutic intervention for neurodegenerative diseases with TDP-43 proteinopathy.

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