scholarly journals Dysregulation of the Autophagy-Endolysosomal System in Amyotrophic Lateral Sclerosis and Related Motor Neuron Diseases

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Asako Otomo ◽  
Lei Pan ◽  
Shinji Hadano

Amyotrophic lateral sclerosis (ALS) is a heterogeneous group of incurable motor neuron diseases (MNDs) characterized by a selective loss of upper and lower motor neurons in the brain and spinal cord. Most cases of ALS are sporadic, while approximately 5–10% cases are familial. More than 16 causative genes for ALS/MNDs have been identified and their underlying pathogenesis, including oxidative stress, endoplasmic reticulum stress, excitotoxicity, mitochondrial dysfunction, neural inflammation, protein misfolding and accumulation, dysfunctional intracellular trafficking, abnormal RNA processing, and noncell-autonomous damage, has begun to emerge. It is currently believed that a complex interplay of multiple toxicity pathways is implicated in disease onset and progression. Among such mechanisms, ones that are associated with disturbances of protein homeostasis, the ubiquitin-proteasome system and autophagy, have recently been highlighted. Although it remains to be determined whether disease-associated protein aggregates have a toxic or protective role in the pathogenesis, the formation of them results from the imbalance between generation and degradation of misfolded proteins within neuronal cells. In this paper, we focus on the autophagy-lysosomal and endocytic degradation systems and implication of their dysfunction to the pathogenesis of ALS/MNDs. The autophagy-endolysosomal pathway could be a major target for the development of therapeutic agents for ALS/MNDs.

2019 ◽  
Vol 27 (4) ◽  
pp. 1369-1382 ◽  
Author(s):  
Honglin Tan ◽  
Mina Chen ◽  
Dejiang Pang ◽  
Xiaoqiang Xia ◽  
Chongyangzi Du ◽  
...  

Abstract Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive loss of motor neurons. Improving neuronal survival in ALS remains a significant challenge. Previously, we identified Lanthionine synthetase C-like protein 1 (LanCL1) as a neuronal antioxidant defense gene, the genetic deletion of which causes apoptotic neurodegeneration in the brain. Here, we report in vivo data using the transgenic SOD1G93A mouse model of ALS indicating that CNS-specific expression of LanCL1 transgene extends lifespan, delays disease onset, decelerates symptomatic progression, and improves motor performance of SOD1G93A mice. Conversely, CNS-specific deletion of LanCL1 leads to neurodegenerative phenotypes, including motor neuron loss, neuroinflammation, and oxidative damage. Analysis reveals that LanCL1 is a positive regulator of AKT activity, and LanCL1 overexpression restores the impaired AKT activity in ALS model mice. These findings indicate that LanCL1 regulates neuronal survival through an alternative mechanism, and suggest a new therapeutic target in ALS.


2020 ◽  
Vol 10 (3) ◽  
pp. 58 ◽  
Author(s):  
Owen Connolly ◽  
Laura Le Gall ◽  
Gavin McCluskey ◽  
Colette G Donaghy ◽  
William J Duddy ◽  
...  

Amyotrophic lateral sclerosis is a rare and fatal neurodegenerative disease characterised by progressive deterioration of upper and lower motor neurons that eventually culminates in severe muscle atrophy, respiratory failure and death. There is a concerning lack of understanding regarding the mechanisms that lead to the onset of ALS and as a result there are no reliable biomarkers that aid in the early detection of the disease nor is there an effective treatment. This review first considers the clinical phenotypes associated with ALS, and discusses the broad categorisation of ALS and ALS-mimic diseases into upper and lower motor neuron diseases, before focusing on the genetic aetiology of ALS and considering the potential relationship of mutations of different genes to variations in phenotype. For this purpose, a systematic review is conducted collating data from 107 original published clinical studies on monogenic forms of the disease, surveying the age and site of onset, disease duration and motor neuron involvement. The collected data highlight the complexity of the disease’s genotype–phenotype relationship, and thus the need for a nuanced approach to the development of clinical assays and therapeutics.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Doris Tomas ◽  
Victoria M. McLeod ◽  
Mathew D. F. Chiam ◽  
Nayomi Wanniarachchillage ◽  
Wah C. Boon ◽  
...  

AbstractAmyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder caused by loss of motor neurons. ALS incidence is skewed towards males with typically earlier age of onset and limb site of onset. The androgen receptor (AR) is the major mediator of androgen effects in the body and is present extensively throughout the central nervous system, including motor neurons. Mutations in the AR gene lead to selective lower motor neuron degeneration in male spinal bulbar muscular atrophy (SBMA) patients, emphasising the importance of AR in maintaining motor neuron health and survival. To evaluate a potential role of AR in onset and progression of ALS, we generated SOD1G93A mice with either neural AR deletion or global human AR overexpression. Using a Cre-LoxP conditional gene knockout strategy, we report that neural deletion of AR has minimal impact on the disease course in SOD1G93A male mice. This outcome was potentially confounded by the metabolically disrupted Nestin-Cre phenotype, which likely conferred the profound lifespan extension observed in the SOD1G93A double transgenic male mice. In addition, overexpression of human AR produced no benefit to disease onset and progression in SOD1G93A mice. In conclusion, the disease course of SOD1G93A mice is independent of AR expression levels, implicating other mechanisms involved in mediating the sex differences in ALS. Our findings using Nestin-Cre mice, which show an inherent metabolic phenotype, led us to hypothesise that targeting hypermetabolism associated with ALS may be a more potent modulator of disease, than AR in this mouse model.


2022 ◽  
Vol 7 (4) ◽  
pp. 292-294
Author(s):  
Aarti Chopra ◽  
Ravi Kumar ◽  
Girendra Kumar Gautam

Motor neuron diseases are a group of chronic sporadic and hereditary neurological disorders characterized by progressive degeneration of motor neurons. These might affect the upper motor neurons, lower motor neurons, or both. The prognosis of the motor neuron disease depends upon the age at onset and the area of the central nervous system affected. Amyotrophic lateral sclerosis (ALS) has been documented to be fatal within three years of onset. This activity focuses on amyotrophic lateral sclerosis as the prototype of MND, which affects both the upper and the lower motor neurons and discusses the role of inter-professional team in the differential diagnosis, evaluation, treatment, and prognostication. It also discusses various other phenotypes of MND with an emphasis on their distinguishing features in requisite detail.


Author(s):  
Nimish Thakore ◽  
Erik P Pioro

Disorders of lower motor neurons (LMNs, or anterior horn cells) and upper motor neurons (UMNs), jointly termed motor neuron disorders (MNDs), are diverse and numerous. The prototypical MND, namely amyotrophic lateral sclerosis (ALS), a relentlessly progressive lethal disorder of adults, is the subject of another section and will not be discussed further here. Other MNDs include spinal muscular atrophy (SMA), of which there are four types: Kennedy’s disease, Brown-Violetto-Van Laere, and Fazio-Londe syndromes, lower motor neuron disorders as part of neurodegenerations and secondary motor neuron disease as part of malignancy, radiation and infection.


2014 ◽  
Vol 2014 ◽  
pp. 1-3 ◽  
Author(s):  
Mohammad Hasan Namazi ◽  
Isa Khaheshi ◽  
Habib Haybar ◽  
Shooka Esmaeeli

Amyotrophic lateral sclerosis (ALS) is the most well-known form of motor neuron diseases in which both upper and lower motor neurons are involved in this disease. We presented an unusual case of ALS whom had presented with chief complaint of dyspnea. Cardiac failure was diagnosed at the final stage of the ALS disease. The pathogenetic mechanism leading to an elevated occurrence of cardiomyopathy in ALS is not comprehensible. Dilated cardiomyopathy has been explained in some previous studies. Based on the collected data, it was hypothesized that cardiomyopathy is underdiagnosed in the ALS population, probably because symptoms are masqueraded as a result of the patients’ disability. It was suggested that in all motor neuron diseases a serial cardiological evaluation should be executed, including annual echocardiography.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Estela Area-Gomez ◽  
D. Larrea ◽  
T. Yun ◽  
Y. Xu ◽  
J. Hupf ◽  
...  

AbstractMotor neuron disorders (MND) include a group of pathologies that affect upper and/or lower motor neurons. Among them, amyotrophic lateral sclerosis (ALS) is characterized by progressive muscle weakness, with fatal outcomes only in a few years after diagnosis. On the other hand, primary lateral sclerosis (PLS), a more benign form of MND that only affects upper motor neurons, results in life-long progressive motor dysfunction. Although the outcomes are quite different, ALS and PLS present with similar symptoms at disease onset, to the degree that both disorders could be considered part of a continuum. These similarities and the lack of reliable biomarkers often result in delays in accurate diagnosis and/or treatment. In the nervous system, lipids exert a wide variety of functions, including roles in cell structure, synaptic transmission, and multiple metabolic processes. Thus, the study of the absolute and relative concentrations of a subset of lipids in human pathology can shed light into these cellular processes and unravel alterations in one or more pathways. In here, we report the lipid composition of longitudinal plasma samples from ALS and PLS patients initially, and after 2 years following enrollment in a clinical study. Our analysis revealed common aspects of these pathologies suggesting that, from the lipidomics point of view, PLS and ALS behave as part of a continuum of motor neuron disorders.


2021 ◽  
Vol 11 (2) ◽  
pp. 160
Author(s):  
Mor R. Alkaslasi ◽  
Noell E. Cho ◽  
Navpreet K. Dhillon ◽  
Oksana Shelest ◽  
Patricia S. Haro-Lopez ◽  
...  

Traumatic brain injury (TBI) is a well-established risk factor for several neurodegenerative disorders including Alzheimer’s disease and Parkinson’s disease, however, a link between TBI and amyotrophic lateral sclerosis (ALS) has not been clearly elucidated. Using the SOD1G93A rat model known to recapitulate the human ALS condition, we found that exposure to mild, repetitive TBI lead ALS rats to experience earlier disease onset and shortened survival relative to their sham counterparts. Importantly, increased severity of early injury symptoms prior to the onset of ALS disease symptoms was linked to poor health of corticospinal motor neurons and predicted worsened outcome later in life. Whereas ALS rats with only mild behavioral injury deficits exhibited no observable changes in corticospinal motor neuron health and did not present with early onset or shortened survival, those with more severe injury-related deficits exhibited alterations in corticospinal motor neuron health and presented with significantly earlier onset and shortened lifespan. While these studies do not imply that TBI causes ALS, we provide experimental evidence that head injury is a risk factor for earlier disease onset in a genetically predisposed ALS population and is associated with poor health of corticospinal motor neurons.


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