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

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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Glial Cells—The Strategic Targets in Amyotrophic Lateral Sclerosis Treatment

Journal of Clinical Medicine ◽

10.3390/jcm9010261 ◽

2020 ◽

Vol 9 (1) ◽

pp. 261 ◽

Cited By ~ 2

Author(s):

Tereza Filipi ◽

Zuzana Hermanova ◽

Jana Tureckova ◽

Ondrej Vanatko ◽

Miroslava Anderova

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Motor Neurons ◽

Current Knowledge ◽

Gene Mutations ◽

Cell Types ◽

In Vivo Models ◽

Cell Therapies ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurological disease, which is characterized by the degeneration of motor neurons in the motor cortex and the spinal cord and subsequently by muscle atrophy. To date, numerous gene mutations have been linked to both sporadic and familial ALS, but the effort of many experimental groups to develop a suitable therapy has not, as of yet, proven successful. The original focus was on the degenerating motor neurons, when researchers tried to understand the pathological mechanisms that cause their slow death. However, it was soon discovered that ALS is a complicated and diverse pathology, where not only neurons, but also other cell types, play a crucial role via the so-called non-cell autonomous effect, which strongly deteriorates neuronal conditions. Subsequently, variable glia-based in vitro and in vivo models of ALS were established and used for brand-new experimental and clinical approaches. Such a shift towards glia soon bore its fruit in the form of several clinical studies, which more or less successfully tried to ward the unfavourable prognosis of ALS progression off. In this review, we aimed to summarize current knowledge regarding the involvement of each glial cell type in the progression of ALS, currently available treatments, and to provide an overview of diverse clinical trials covering pharmacological approaches, gene, and cell therapies.

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Pathological Roles of Wild-Type Cu, Zn-Superoxide Dismutase in Amyotrophic Lateral Sclerosis

Neurology Research International ◽

10.1155/2012/323261 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Yoshiaki Furukawa

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Superoxide Dismutase ◽

Motor Neurons ◽

Wild Type ◽

Sporadic Als ◽

Familial Form ◽

Recent Developments ◽

Lateral Sclerosis

Dominant mutations in a Cu, Zn-superoxide dismutase (SOD1) gene cause a familial form of amyotrophic lateral sclerosis (ALS). While it remains controversial how SOD1 mutations lead to onset and progression of the disease, manyin vitroandin vivostudies have supported a gain-of-toxicity mechanism where pathogenic mutations contribute to destabilizing a native structure of SOD1 and thus facilitate misfolding and aggregation. Indeed, abnormal accumulation of SOD1-positive inclusions in spinal motor neurons is a pathological hallmark in SOD1-related familial ALS. Furthermore, similarities in clinical phenotypes and neuropathology of ALS cases with and without mutations insod1gene have implied a disease mechanism involving SOD1 common to all ALS cases. Although pathogenic roles of wild-type SOD1 in sporadic ALS remain controversial, recent developments of novel SOD1 antibodies have made it possible to characterize wild-type SOD1 under pathological conditions of ALS. Here, I have briefly reviewed recent progress on biochemical and immunohistochemical characterization of wild-type SOD1 in sporadic ALS cases and discussed possible involvement of wild-type SOD1 in a pathomechanism of ALS.

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Plants-Derived Neuroprotective Agents: Cutting the Cycle of Cell Death through Multiple Mechanisms

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2017/3574012 ◽

2017 ◽

Vol 2017 ◽

pp. 1-27 ◽

Cited By ~ 17

Author(s):

Taiwo Olayemi Elufioye ◽

Tomayo Ireti Berida ◽

Solomon Habtemariam

Keyword(s):

Mechanisms Of Action ◽

Neuroprotective Agents ◽

Structural Class ◽

Molecular Features ◽

Amyotropic Lateral Sclerosis ◽

Underlying Mechanisms ◽

And Function ◽

Lateral Sclerosis

Neuroprotection is the preservation of the structure and function of neurons from insults arising from cellular injuries induced by a variety of agents or neurodegenerative diseases (NDs). The various NDs including Alzheimer’s, Parkinson’s, and Huntington’s diseases as well as amyotropic lateral sclerosis affect millions of people around the world with the main risk factor being advancing age. Each of these diseases affects specific neurons and/or regions in the brain and involves characteristic pathological and molecular features. Hence, several in vitro and in vivo study models specific to each disease have been employed to study NDs with the aim of understanding their underlying mechanisms and identifying new therapeutic strategies. Of the most prevalent drug development efforts employed in the past few decades, mechanisms implicated in the accumulation of protein-based deposits, oxidative stress, neuroinflammation, and certain neurotransmitter deficits such as acetylcholine and dopamine have been scrutinized in great detail. In this review, we presented classical examples of plant-derived neuroprotective agents by highlighting their structural class and specific mechanisms of action. Many of these natural products that have shown therapeutic efficacies appear to be working through the above-mentioned key multiple mechanisms of action.

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FUS-ALS mutants alter FMRP phase separation equilibrium and impair protein translation

Science Advances ◽

10.1126/sciadv.abf8660 ◽

2021 ◽

Vol 7 (30) ◽

pp. eabf8660

Author(s):

Nicol Birsa ◽

Agnieszka M. Ule ◽

Maria Giovanna Garone ◽

Brian Tsang ◽

Francesca Mattedi ◽

...

Keyword(s):

Phase Separation ◽

Motor Neurons ◽

Rna Binding ◽

Fragile X ◽

Protein Translation ◽

Fused In Sarcoma ◽

Mental Retardation Protein ◽

Lateral Sclerosis

FUsed in Sarcoma (FUS) is a multifunctional RNA binding protein (RBP). FUS mutations lead to its cytoplasmic mislocalization and cause the neurodegenerative disease amyotrophic lateral sclerosis (ALS). Here, we use mouse and human models with endogenous ALS-associated mutations to study the early consequences of increased cytoplasmic FUS. We show that in axons, mutant FUS condensates sequester and promote the phase separation of fragile X mental retardation protein (FMRP), another RBP associated with neurodegeneration. This leads to repression of translation in mouse and human FUS-ALS motor neurons and is corroborated in vitro, where FUS and FMRP copartition and repress translation. Last, we show that translation of FMRP-bound RNAs is reduced in vivo in FUS-ALS motor neurons. Our results unravel new pathomechanisms of FUS-ALS and identify a novel paradigm by which mutations in one RBP favor the formation of condensates sequestering other RBPs, affecting crucial biological functions, such as protein translation.

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Amyotrophic Lateral Sclerosis and Autophagy: Dysfunction and Therapeutic Targeting

Cells ◽

10.3390/cells9112413 ◽

2020 ◽

Vol 9 (11) ◽

pp. 2413

Author(s):

Azin Amin ◽

Nirma D. Perera ◽

Philip M. Beart ◽

Bradley J. Turner ◽

Fazel Shabanpoor

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Motor Neurons ◽

Protein Aggregates ◽

Misfolded Proteins ◽

Protein Aggregate ◽

In Vivo Models ◽

Primary Stress ◽

Lateral Sclerosis

Over the past 20 years, there has been a drastically increased understanding of the genetic basis of Amyotrophic Lateral Sclerosis. Despite the identification of more than 40 different ALS-causing mutations, the accumulation of neurotoxic misfolded proteins, inclusions, and aggregates within motor neurons is the main pathological hallmark in all cases of ALS. These protein aggregates are proposed to disrupt cellular processes and ultimately result in neurodegeneration. One of the main reasons implicated in the accumulation of protein aggregates may be defective autophagy, a highly conserved intracellular “clearance” system delivering misfolded proteins, aggregates, and damaged organelles to lysosomes for degradation. Autophagy is one of the primary stress response mechanisms activated in highly sensitive and specialised neurons following insult to ensure their survival. The upregulation of autophagy through pharmacological autophagy-inducing agents has largely been shown to reduce intracellular protein aggregate levels and disease phenotypes in different in vitro and in vivo models of neurodegenerative diseases. In this review, we explore the intriguing interface between ALS and autophagy, provide a most comprehensive summary of autophagy-targeted drugs that have been examined or are being developed as potential treatments for ALS to date, and discuss potential therapeutic strategies for targeting autophagy in ALS.

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A comparative structural analysis of sepiapterin reductase from Drosophila by homology modeling

Pteridines ◽

10.1515/pterid-2014-0017 ◽

2015 ◽

Vol 26 (2) ◽

pp. 55-61 ◽

Cited By ~ 1

Author(s):

Kiyoung Kim ◽

Keon-Hyoung Song ◽

Jeongbin Yim

Keyword(s):

Homology Modeling ◽

Structural Characteristics ◽

Valuable Insight ◽

Gene Encoding ◽

Sepiapterin Reductase ◽

Modeling Analysis ◽

Different Shapes ◽

And Function

AbstractSepiapterin reductase (SR) catalyzes the final steps of BH4 biosynthesis. Previously, a gene encoding SR has been cloned and characterized from a Drosophila cDNA library in vitro. The present study reports the identification of another SR gene in the Drosophila genome and the structural characteristics and differences of the two Drosophila SRs, using homology modeling analysis. Homology modeling of SRs for protein structure and function prediction showed that the two SRs have different surface electrostatic distributions and different shapes of the substrate (sepiapterin)-binding sites. These results provide valuable insight into the possibility of diverse functions of Drosophila SRs in vivo.

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Alterations in Tau Metabolism in ALS and ALS-FTSD

Frontiers in Neurology ◽

10.3389/fneur.2020.598907 ◽

2020 ◽

Vol 11 ◽

Author(s):

Michael J. Strong ◽

Neil S. Donison ◽

Kathryn Volkening

Keyword(s):

Motor Neurons ◽

Chronic Traumatic Encephalopathy ◽

Dna Binding Protein ◽

Tau Phosphorylation ◽

Protein Tau ◽

Oligomer Formation ◽

Biological Heterogeneity ◽

Lateral Sclerosis

There is increasing acceptance that amyotrophic lateral sclerosis (ALS), classically considered a neurodegenerative disease affecting almost exclusively motor neurons, is syndromic with both clinical and biological heterogeneity. This is most evident in its association with a broad range of neuropsychological, behavioral, speech and language deficits [collectively termed ALS frontotemporal spectrum disorder (ALS-FTSD)]. Although the most consistent pathology of ALS and ALS-FTSD is a disturbance in TAR DNA binding protein 43 kDa (TDP-43) metabolism, alterations in microtubule-associated tau protein (tau) metabolism can also be observed in ALS-FTSD, most prominently as pathological phosphorylation at Thr175 (pThr175tau). pThr175 has been shown to promote exposure of the phosphatase activating domain (PAD) in the tau N-terminus with the consequent activation of GSK3β mediated phosphorylation at Thr231 (pThr231tau) leading to pathological oligomer formation. This pathological cascade of tau phosphorylation has been observed in chronic traumatic encephalopathy with ALS (CTE-ALS) and in both in vivo and in vitro experimental paradigms, suggesting that it is of critical relevance to the pathobiology of ALS-FTSD. It is also evident that the co-existence of alterations in the metabolism of TDP-43 and tau acts synergistically in a rodent model to exacerbate the pathology of either.

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A Novel Bioengineered Functional Motor Unit Platform to Study Neuromuscular Interaction

Journal of Clinical Medicine ◽

10.3390/jcm9103238 ◽

2020 ◽

Vol 9 (10) ◽

pp. 3238

Author(s):

Jasdeep Saini ◽

Alessandro Faroni ◽

Adam J. Reid ◽

Kamel Mamchaoui ◽

Vincent Mouly ◽

...

Keyword(s):

Motor Unit ◽

Motor Neurons ◽

Acetylcholine Receptors ◽

In Vivo Studies ◽

Cholinergic Antagonists ◽

Myoblast Cell ◽

Nerve Muscle ◽

And Function

Background: In many neurodegenerative and muscular disorders, and loss of innervation in sarcopenia, improper reinnervation of muscle and dysfunction of the motor unit (MU) are key pathogenic features. In vivo studies of MUs are constrained due to difficulties isolating and extracting functional MUs, so there is a need for a simplified and reproducible system of engineered in vitro MUs. Objective: to develop and characterise a functional MU model in vitro, permitting the analysis of MU development and function. Methods: an immortalised human myoblast cell line was co-cultured with rat embryo spinal cord explants in a serum-free/growth fact media. MUs developed and the morphology of their components (neuromuscular junction (NMJ), myotubes and motor neurons) were characterised using immunocytochemistry, phase contrast and confocal microscopy. The function of the MU was evaluated through live observations and videography of spontaneous myotube contractions after challenge with cholinergic antagonists and glutamatergic agonists. Results: blocking acetylcholine receptors with α-bungarotoxin resulted in complete, cessation of myotube contractions, which was reversible with tubocurarine. Furthermore, myotube activity was significantly higher with the application of L-glutamic acid. All these observations indicate the formed MU are functional. Conclusion: a functional nerve-muscle co-culture model was established that has potential for drug screening and pathophysiological studies of neuromuscular interactions.

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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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Haploinsufficiency of the TDP43 ubiquitin E3 ligase RNF220 leads to ALS-like motor neuron defects in the mouse

Journal of Molecular Cell Biology ◽

10.1093/jmcb/mjaa072 ◽

2021 ◽

Author(s):

Pengcheng Ma ◽

Yuwei Li ◽

Huishan Wang ◽

Bingyu Mao

Keyword(s):

Motor Neurons ◽

Regulatory Protein ◽

E3 Ligase ◽

Subcellular Location ◽

Spinal Motor Neurons ◽

Ubiquitin E3 Ligase ◽

Lateral Sclerosis

Abstract TDP43 pathology is seen in a large majority of amyotrophic lateral sclerosis (ALS) cases, suggesting a central pathogenic role of this regulatory protein. Clarifying the molecular mechanism controlling TDP43 stability and subcellular location might provide important insights into ALS therapy. The ubiquitin E3 ligase RNF220 is involved in different neural developmental processes through various molecular targets in the mouse. Here, we report that the RNF220+/- mice showed progressively decreasing mobility to different extents, some of which developed typical ALS pathological characteristics in spinal motor neurons, including TDP43 cytoplasmic accumulation, atrocytosis, muscle denervation, and atrophy. Mechanistically, RNF220 interacts with TDP43 in vitro and in vivo and promotes its polyubiquitination and proteasomal degradation. In conclusion, we propose that RNF220 might be a modifier of TDP43 function in vivo and contribute to TDP43 pathology in neurodegenerative disease like ALS.

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