scholarly journals ALS motor neurons exhibit hallmark metabolic defects that are rescued by SIRT3 activation

2020 ◽  
Author(s):  
Jin-Hui Hor ◽  
Munirah Mohamad Santosa ◽  
Valerie Jing Wen Lim ◽  
Beatrice Xuan Ho ◽  
Amy Taylor ◽  
...  
Keyword(s):  
Motor Neurons ◽  
Cortical Neurons ◽  
Metabolic Flux ◽  
Metabolic Profiles ◽  
Metabolic Defects ◽  
Sporadic Als ◽  
Altered Metabolism ◽  
Induced Pluripotent ◽  
Als Patients ◽  
Lateral Sclerosis

Abstract Motor neurons (MNs) are highly energetic cells and recent studies suggest that altered energy metabolism precede MN loss in amyotrophic lateral sclerosis (ALS), an age-onset neurodegenerative disease. However, clear mechanistic insights linking altered metabolism and MN death are still missing. In this study, induced pluripotent stem cells from healthy controls, familial ALS, and sporadic ALS patients were differentiated toward spinal MNs, cortical neurons, and cardiomyocytes. Metabolic flux analyses reveal an MN-specific deficiency in mitochondrial respiration in ALS. Intriguingly, all forms of familial and sporadic ALS MNs tested in our study exhibited similar defective metabolic profiles, which were attributed to hyper-acetylation of mitochondrial proteins. In the mitochondria, Sirtuin-3 (SIRT3) functions as a mitochondrial deacetylase to maintain mitochondrial function and integrity. We found that activating SIRT3 using nicotinamide or a small molecule activator reversed the defective metabolic profiles in all our ALS MNs, as well as correct a constellation of ALS-associated phenotypes.

scholarly journals ALS Motor Neurons Exhibit Hallmark Metabolic Defects That Are Rescued by Nicotinamide and SIRT3 Activation

2019 ◽  
Author(s):  
Jin-Hui Hor ◽  
Munirah Mohamad Santosa ◽  
Valerie Jing Wen Lim ◽  
Beatrice Xuan Ho ◽  
Amy Taylor ◽  
...  
Keyword(s):  
Motor Neurons ◽  
Cortical Neurons ◽  
Metabolic Flux ◽  
Metabolic Profiles ◽  
Metabolic Defects ◽  
Sporadic Als ◽  
Altered Metabolism ◽  
Induced Pluripotent ◽  
Als Patients ◽  
Lateral Sclerosis

SUMMARYMotor neurons (MNs) are highly energetic cells and recent studies suggest that altered energy metabolism precede MN loss in Amyotrophic Lateral Sclerosis (ALS), an age-onset neurodegenerative disease. However, clear mechanistic insights linking altered metabolism and MN death are still missing. In this study, induced pluripotent stem cells (iPSCs) from healthy controls, familial ALS and sporadic ALS patients were differentiated towards spinal MNs, cortical neurons and cardiomyocytes. Metabolic flux analyses reveal a MN-specific deficiency in mitochondrial respiration in ALS. Intriguingly, all forms of familial and sporadic ALS MNs tested in our study exhibited similar defective metabolic profiles, which were attributed to hyper-acetylation of mitochondrial proteins. In the mitochondria, SIRT3 functions as a mitochondrial deacetylase to maintain mitochondrial function and integrity. We found that activating SIRT3 using nicotinamide or a small molecule activator reversed the defective metabolic profiles in all our ALS MNs, as well as correct a constellation of ALS-associated phenotypes.

scholarly journals Genome Wide Analysis Points towards Subtype-Specific Diseases in Different Genetic Forms of Amyotrophic Lateral Sclerosis

2020 ◽  
Vol 21 (18) ◽  
pp. 6938
Author(s):  
Banaja P. Dash ◽  
Marcel Naumann ◽  
Jared Sterneckert ◽  
Andreas Hermann
Keyword(s):  
Motor Neurons ◽  
Individualized Medicine ◽  
Induced Pluripotent Stem Cell ◽  
Kegg Pathways ◽  
Amyotropic Lateral Sclerosis ◽  
Sporadic Als ◽  
Apparent Death ◽  
Induced Pluripotent ◽  
Simplex Virus ◽  
Lateral Sclerosis

Amyotropic lateral sclerosis (ALS) is a lethally progressive and irreversible neurodegenerative disease marked by apparent death of motor neurons present in the spinal cord, brain stem and motor cortex. While more and more gene mutants being established for genetic ALS, the vast majority suffer from sporadic ALS (>90%). It has been challenging, thus, to model sporadic ALS which is one reason why the underlying pathophysiology remains elusive and has stalled the development of therapeutic strategies of this progressive motor neuron disease. To further unravel these pathological signaling pathways, human induced pluripotent stem cell (hiPSCs)-derived motor neurons (MNs) from FUS- and SOD1 ALS patients and healthy controls were systematically compared to independent published datasets. Here through this study we created a gene profile of ALS by analyzing the DEGs, the Kyoto encyclopedia of Genes and Genomes (KEGG) pathways, the interactome and the transcription factor profiles (TF) that would identify altered molecular/functional signatures and their interactions at both transcriptional (mRNAs) and translational levels (hub proteins and TFs). Our findings suggest that FUS and SOD1 may develop from dysregulation in several unique pathways and herpes simplex virus (HSV) infection was among the topmost predominant cellular pathways connected to FUS and not to SOD1. In contrast, SOD1 is mainly characterized by alterations in the metabolic pathways and alterations in the neuroactive-ligand–receptor interactions. This suggests that different genetic ALS forms are singular diseases rather than part of a common spectrum. This is important for patient stratification clearly pointing towards the need for individualized medicine approaches in ALS.

scholarly journals The Src/c-Abl pathway is a potential therapeutic target in amyotrophic lateral sclerosis

2017 ◽  
Vol 9 (391) ◽  
pp. eaaf3962 ◽  
Author(s):  
Keiko Imamura ◽  
Yuishin Izumi ◽  
Akira Watanabe ◽  
Kayoko Tsukita ◽  
Knut Woltjen ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neuron ◽  
Motor Neurons ◽  
New Drugs ◽  
Small Interfering Rnas ◽  
Altered Expression ◽  
Sporadic Als ◽  
Induced Pluripotent ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS), a fatal disease causing progressive loss of motor neurons, still has no effective treatment. We developed a phenotypic screen to repurpose existing drugs using ALS motor neuron survival as readout. Motor neurons were generated from induced pluripotent stem cells (iPSCs) derived from an ALS patient with a mutation in superoxide dismutase 1 (SOD1). Results of the screen showed that more than half of the hits targeted the Src/c-Abl signaling pathway. Src/c-Abl inhibitors increased survival of ALS iPSC-derived motor neurons in vitro. Knockdown of Src or c-Abl with small interfering RNAs (siRNAs) also rescued ALS motor neuron degeneration. One of the hits, bosutinib, boosted autophagy, reduced the amount of misfolded mutant SOD1 protein, and attenuated altered expression of mitochondrial genes. Bosutinib also increased survival in vitro of ALS iPSC-derived motor neurons from patients with sporadic ALS or other forms of familial ALS caused by mutations in TAR DNA binding protein (TDP-43) or repeat expansions in C9orf72. Furthermore, bosutinib treatment modestly extended survival of a mouse model of ALS with an SOD1 mutation, suggesting that Src/c-Abl may be a potentially useful target for developing new drugs to treat ALS.

scholarly journals Motor neurons from ALS patients with mutations in C9ORF72 and SOD1 exhibit distinct transcriptional landscapes

2019 ◽  
Vol 28 (16) ◽  
pp. 2799-2810 ◽  
Author(s):  
Ching-On Wong ◽  
Kartik Venkatachalam
Keyword(s):  
Cell Adhesion ◽  
Motor Neurons ◽  
Induced Pluripotent Stem Cell ◽  
Data Sets ◽  
Spinal Motor Neurons ◽  
Expression Of Genes ◽  
Sporadic Als ◽  
Elevated Expression ◽  
Induced Pluripotent ◽  
Als Patients

Abstract Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease that culminates in paralysis and death. Here, we present our analyses of publicly available multiOMIC data sets generated using motor neurons from ALS patients and control cohorts. Functional annotation of differentially expressed genes in induced pluripotent stem cell (iPSC)-derived motor neurons generated from patients with mutations in C9ORF72 (C9-ALS) suggests elevated expression of genes that pertain to extracellular matrix (ECM) and cell adhesion, inflammation and TGFβ targets. On the other end of the continuum, we detected diminished expression of genes repressed by quiescence-promoting E2F4/DREAM complex. Proteins whose abundance was significantly altered in C9-ALS neurons faithfully recapitulated the transcriptional aberrations. Importantly, patterns of gene expression in spinal motor neurons dissected from C9-ALS or sporadic ALS patients were highly concordant with each other and with the C9-ALS iPSC neurons. In contrast, motor neurons from patients with mutations in SOD1 exhibited dramatically different signatures. Elevated expression of gene sets such as ECM and cell adhesion genes occurs in C9 and sporadic ALS but not SOD1-ALS. These analyses indicate that despite the similarities in outward manifestations, transcriptional and proteomic signatures in ALS motor neurons can vary significantly depending on the identity of the causal mutations.

scholarly journals Glial Cells in Amyotrophic Lateral Sclerosis

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Jurate Lasiene ◽  
Koji Yamanaka
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neuron ◽  
Glial Cells ◽  
Motor Neurons ◽  
Premature Death ◽  
Active Role ◽  
Sporadic Als ◽  
Neuron Damage ◽  
Als Patients ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is an adult motor neuron disease characterized by premature death of upper and lower motor neurons. Two percent of ALS cases are caused by the dominant mutations in the gene for superoxide dismutase 1 (SOD1) through a gain of toxic property of mutant protein. Genetic and chimeric mice studies using SOD1 models indicate that non-neuronal cells play important roles in neurodegeneration through non-cell autonomous mechanism. We review the contribution of each glial cell type in ALS pathology from studies of the rodent models and ALS patients. Astrogliosis and microgliosis are not only considerable hallmarks of the disease, but the intensity of microglial activation is correlated with severity of motor neuron damage in human ALS. The impaired astrocytic functions such as clearance of extracellular glutamate and release of neurotrophic factors are implicated in disease. Further, the damage within astrocytes and microglia is involved in accelerated disease progression. Finally, other glial cells such as NG2 cells, oligodendrocytes and Schwann cells are under the investigation to determine their contribution in ALS. Accumulating knowledge of active role of glial cells in the disease should be carefully applied to understanding of the sporadic ALS and development of therapy targeted for glial cells.

scholarly journals Postmortem Cortex Samples Identify Distinct Molecular Subtypes of ALS: Retrotransposon Activation, Oxidative Stress, and Activated Glia

2019 ◽  
Author(s):  
Oliver H. Tam ◽  
Nikolay V. Rozhkov ◽  
Regina Shaw ◽  
Duyang Kim ◽  
Isabel Hubbard ◽  
...  
Keyword(s):  
Motor Neurons ◽  
Molecular Subtypes ◽  
Machine Learning Algorithms ◽  
Tissue Samples ◽  
Proteotoxic Stress ◽  
Sporadic Als ◽  
History Of ◽  
Als Patients ◽  
Large Survey ◽  
Lateral Sclerosis

SummaryAmyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons. While several inherited pathogenic mutations have been identified as causative, the vast majority of cases are sporadic with no family history of disease. Thus, for the majority of ALS cases, a specific causal abnormality is not known and the disease may be a product of multiple inter-related pathways contributing to varying degrees in different ALS patients. Using unsupervised machine learning algorithms, we stratified the transcriptomes of 148 ALS decedent cortex tissue samples into three distinct and robust molecular subtypes. The largest cluster, identified in 61% of patient samples, displayed hallmarks of oxidative and proteotoxic stress. Another 20% of the ALS patient samples exhibited high levels of retrotransposon expression and other signatures of TDP-43 dysfunction. Finally, a third group showed predominant signatures of glial activation (19%). Together these results demonstrate that at least three distinct molecular signatures contribute to ALS disease. While multiple dysregulated components and pathways comprising these clusters have previously been implicated in ALS pathogenesis, unbiased analysis of this large survey demonstrated that sporadic ALS patient tissues can be segregated into distinct molecular subsets.

scholarly journals Microglia influence neurofilament deposition in ALS iPSC-derived motor neurons

2022 ◽  
Author(s):  
Reilly L Allison ◽  
Jacob W Adelman ◽  
Jenica Abrudan ◽  
Raul A Urrutia ◽  
Michael T Zimmermann ◽  
...  
Keyword(s):  
Motor Neuron ◽  
Conditioned Medium ◽  
Motor Neurons ◽  
Neuron Loss ◽  
Secreted Factors ◽  
Sporadic Als ◽  
Motor Neuron Loss ◽  
Induced Pluripotent ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in which upper and lower motor neuron loss is the primary phenotype, leading to muscle weakness and wasting, respiratory failure, and death. Although a portion of ALS cases are linked to one of over 50 unique genes, the vast majority of cases are sporadic in nature. However, the mechanisms underlying the motor neuron loss in either familial or sporadic ALS are not entirely clear. Here we used induced pluripotent stem cells derived from a set of identical twin brothers discordant for ALS to assess the role of astrocytes and microglia on the expression and accumulation of neurofilament proteins in motor neurons. We found that motor neurons derived from the affected twin exhibited increased transcript levels of all three neurofilament isoforms and increased expression of phosphorylated neurofilament puncta. We further found that treatment of the motor neurons with astrocyte conditioned medium and microglial conditioned medium significantly impacted neurofilament deposition. Together, these data suggest that glial-secreted factors can alter neurofilament pathology in ALS iPSC-derived motor neurons.

scholarly journals Distinct responses of neurons and astrocytes to TDP-43 proteinopathy in amyotrophic lateral sclerosis

Brain ◽  
2020 ◽  
Vol 143 (2) ◽  
pp. 430-440 ◽  
Author(s):  
Phillip Smethurst ◽  
Emmanuel Risse ◽  
Giulia E Tyzack ◽  
Jamie S Mitchell ◽  
Doaa M Taha ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neurons ◽  
Induced Pluripotent Stem Cell ◽  
Pathological Feature ◽  
Cell Type ◽  
Sporadic Als ◽  
Cell Type Specific ◽  
Induced Pluripotent ◽  
Human Ipsc ◽  
Lateral Sclerosis

Abstract Amyotrophic lateral sclerosis (ALS) is a fatal and incurable neurodegenerative disease caused by motor neuron loss, resulting in muscle wasting, paralysis and eventual death. A key pathological feature of ALS is cytoplasmically mislocalized and aggregated TDP-43 protein in >95% of cases, which is considered to have prion-like properties. Historical studies have predominantly focused on genetic forms of ALS, which represent ∼10% of cases, leaving the remaining 90% of sporadic ALS relatively understudied. Additionally, the role of astrocytes in ALS and their relationship with TDP-43 pathology is also not currently well understood. We have therefore used highly enriched human induced pluripotent stem cell (iPSC)-derived motor neurons and astrocytes to model early cell type-specific features of sporadic ALS. We first demonstrate seeded aggregation of TDP-43 by exposing human iPSC-derived motor neurons to serially passaged sporadic ALS post-mortem tissue (spALS) extracts. Next, we show that human iPSC-derived motor neurons are more vulnerable to TDP-43 aggregation and toxicity compared with their astrocyte counterparts. We demonstrate that these TDP-43 aggregates can more readily propagate from motor neurons into astrocytes in co-culture paradigms. We next found that astrocytes are neuroprotective to seeded aggregation within motor neurons by reducing (mislocalized) cytoplasmic TDP-43, TDP-43 aggregation and cell toxicity. Furthermore, we detected TDP-43 oligomers in these spALS spinal cord extracts, and as such demonstrated that highly purified recombinant TDP-43 oligomers can reproduce this observed cell-type specific toxicity, providing further support to a protein oligomer-mediated toxicity hypothesis in ALS. In summary, we have developed a human, clinically relevant, and cell-type specific modelling platform that recapitulates key aspects of sporadic ALS and uncovers both an initial neuroprotective role for astrocytes and the cell type-specific toxic effect of TDP-43 oligomers.

scholarly journals Motor Neuron Generation from iPSCs from Identical Twins Discordant for Amyotrophic Lateral Sclerosis

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 571 ◽  
Author(s):  
Emily R. Seminary ◽  
Stephanie Santarriaga ◽  
Lynn Wheeler ◽  
Marie Mejaki ◽  
Jenica Abrudan ◽  
...  
Keyword(s):  
Stem Cells ◽  
Amyotrophic Lateral Sclerosis ◽  
Motor Neuron ◽  
Induced Pluripotent Stem Cells ◽  
Motor Neurons ◽  
Pluripotent Stem Cells ◽  
Identical Twins ◽  
Sporadic Als ◽  
Induced Pluripotent ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a complex neurodegenerative disorder characterized by the loss of the upper and lower motor neurons. Approximately 10% of cases are caused by specific mutations in known genes, with the remaining cases having no known genetic link. As such, sporadic cases have been more difficult to model experimentally. Here, we describe the generation and differentiation of ALS induced pluripotent stem cells reprogrammed from discordant identical twins. Whole genome sequencing revealed no relevant mutations in known ALS-causing genes that differ between the twins. As protein aggregation is found in all ALS patients and is thought to contribute to motor neuron death, we sought to characterize the aggregation phenotype of the sporadic ALS induced pluripotent stem cells (iPSCs). Motor neurons from both twins had high levels of insoluble proteins that commonly aggregate in ALS that did not robustly change in response to exogenous glutamate. In contrast, established genetic ALS iPSC lines demonstrated insolubility in a protein- and genotype-dependent manner. Moreover, whereas the genetic ALS lines failed to induce autophagy after glutamate stress, motor neurons from both twins and independent controls did activate this protective pathway. Together, these data indicate that our unique model of sporadic ALS may provide key insights into disease pathology and highlight potential differences between sporadic and familial ALS.

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