scholarly journals Absence of subcerebral projection neurons delays disease onset and extends survival in a mouse model of ALS

2019 ◽  
Author(s):  
Thibaut Burg ◽  
Charlotte Bichara ◽  
Jelena Scekic-Zahirovic ◽  
Mathieu Fischer ◽  
Geoffrey Stuart-Lopez ◽  
...  

AbstractAmyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease of adulthood that affects voluntary motricity and rapidly leads to full paralysis and death. ALS arises from the combined degeneration of motoneurons in the spinal cord and brain stem, responsible for muscle denervation, and corticospinal projection neurons (CSN), responsible for emergence of the upper motor neuron syndrome. Recent studies carried on ALS patients suggest that the disease may initiate in the motor cortex and spread to its projection targets. However, this “corticofugal hypothesis” of ALS has not yet been specifically challenged. Here, we provide a direct test of this hypothesis by genetically removing subcerebral projection neurons (SubCerPN), including CSN, in Sod1G86R mice, a mouse model of ALS. Ablation of the transcription factor Fezf2, leading to the complete absence of all SubCerPN, delays disease onset, reduces weight loss and motor impairment, and increases survival without modifying disease duration. Importantly absence of SubCerPN and CSN also limits pre-symptomatic hyperreflexia. Together, our results demonstrate that major corticofugal tracts are critical to ALS onset, and that SubCerPN and CSN in particular may carry detrimental signals to their downstream targets. In its whole, this study provides first experimental arguments in favour of the corticofugal hypothesis of ALS.

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Ching Serena Kao ◽  
Rebekah van Bruggen ◽  
Jihye Rachel Kim ◽  
Xiao Xiao Lily Chen ◽  
Cadia Chan ◽  
...  

Abstract A missense mutation, S85C, in the MATR3 gene is a genetic cause for amyotrophic lateral sclerosis (ALS). It is unclear how the S85C mutation affects MATR3 function and contributes to disease. Here, we develop a mouse model that harbors the S85C mutation in the endogenous Matr3 locus using the CRISPR/Cas9 system. MATR3 S85C knock-in mice recapitulate behavioral and neuropathological features of early-stage ALS including motor impairment, muscle atrophy, neuromuscular junction defects, Purkinje cell degeneration and neuroinflammation in the cerebellum and spinal cord. Our neuropathology data reveals a loss of MATR3 S85C protein in the cell bodies of Purkinje cells and motor neurons, suggesting that a decrease in functional MATR3 levels or loss of MATR3 function contributes to neuronal defects. Our findings demonstrate that the MATR3 S85C mouse model mimics aspects of early-stage ALS and would be a promising tool for future basic and preclinical research.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Lu Chen ◽  
Yong Chen ◽  
Mingming Zhao ◽  
Lemin Zheng ◽  
Dongsheng Fan

Abstract To compare the plasma concentrations of trimethylamine N-oxide (TMAO) and its precursors in amyotrophic lateral sclerosis (ALS) patients, their spouses and healthy controls and to find associations between gut microbiota metabolites and ALS. ALS patients were recruited at Peking University Third Hospital from January 2015 to December 2018. Information was collected from their spouses at the same time. Age and gender matched healthy controls were recruited from individuals who visited the physical examination center for health checkups. Blood samples were collected after at least 4 h of fasting. Concentrations of the metabolites were quantified using stable isotope dilution liquid chromatography–tandem mass spectrometry. Group differences were analyzed using parametric and nonparametric tests, as appropriate. In this study, 160 patients with ALS were recruited. In these patients, 63 were compared with their spouses, 148 were compared with age and gender matched controls, and 60 were compared with both their spouses and heathy controls in the same time. The carnitine concentration was significantly higher in patients than in their spouses, while there were no significant differences in the concentrations of other metabolites. The carnitine and betaine concentrations were higher, while the choline, TMAO and butyrobetaine concentrations were lower in ALS than in healthy controls. The concentrations of the metabolites in the spouses were more similar to the ALS patients rather than to the healthy controls. In the ALS group, the plasma concentrations of carnitine, betaine, choline and TMAO were inversely related to the severity of upper motor neuron impairment. The TMAO metabolic pathway of the gut microbiota is disturbed in both ALS patients and their spouses, which might suggest that the changes in the gut microbiota occurred before disease onset. The negative correlations between the involvement of UMNs and the concentrations of the metabolites might suggest that the inhibition of this metabolic pathway might lead to a better prognosis in ALS patients.


2020 ◽  
Author(s):  
David Bayer ◽  
Stefano Antonucci ◽  
Hans-Peter Müller ◽  
Luc Dupuis ◽  
Tobias Boeckers ◽  
...  

AbstractIncreased catabolism is a new clinical manifestation of Amyotrophic Lateral Sclerosis. A dysfunction of lateral hypothalamus may drive hypermetabolism in ALS; however, Its causes and anatomical substrates are unknown. We hypothesize that disruption cortico-hypothalamic circuits may impair energy homeostasis in ALS. We used rAAV2 for large-scale projection mapping and image analysis pipeline based on Wholebrain and Ilastik to quantify projections from the forebrain to the latera hypothalamus of the SOD1(G93A) ALS mouse model as well as of the FusΔNLS ALS mouse model. Expanded projections from agranular Insula, ventrolateral orbitofrontal and secondary motor cortex to lateral hypothalamus were found in two independent cohorts of the hypermetabolic SOD1(G93A) ALS model. The non-hypermetabolic FusΔNLS ALS mouse model display a loss of projections from motor cortex but no change in projections from insula and orbitofronal cortex. 3T DTI-MRI data on 83 ALS patients and 65 controls confirmed the disruption of the orbitofrontal-hypothalamic tract in ALS patients. Converging murine and human data demonstrate the selective disruption of hypothalamic inputs in ALS as a factor contributing to the origin of hypermetabolism.Significance statementWe provide a circuit perspective of the recently identified and medically relevant hyper-metabolic phenotype of Amyotrophic Lateral Sclerosis. We demonstrate the selective involvement of orbitofrontal, insular and motor cortex projections to hypothalamus in murine ALS models and in human patients. The enhanced pipeline for large-scale registration, segmentation projections mapping, the identification of new circuits target of neurodegeneration, and the relevance of these circuits in metabolic disturbances make this work relevant not only for the investigation of ALS but also for other neurodegenerative disease as well as for all conditions characterized by systemic energy imbalances.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Michael R. Strickland ◽  
Kristen R. Ibanez ◽  
Mariya Yaroshenko ◽  
Carolina Ceballos Diaz ◽  
David R. Borchelt ◽  
...  

AbstractInflammatory signaling is thought to modulate the neurodegenerative cascade in amyotrophic lateral sclerosis (ALS). We have previously shown that expression of Interleukin-10 (IL-10), a classical anti-inflammatory cytokine, extends lifespan in the SOD1-G93A mouse model of familial ALS. Here we test whether co-expression of the decoy chemokine receptor M3, that can scavenge inflammatory chemokines, augments the efficacy of IL-10. We found that recombinant adeno-associated virus (AAV)-mediated expression of IL-10, alone, or in combination with M3, resulted in modest extension of lifespan relative to control SOD1-G93A cohort. Interestingly neither AAV-M3 alone nor AAV-IL-10 + AAV-M3 extend survival beyond that of the AAV-IL-10 alone cohort. Focused transcriptomic analysis revealed induction of innate immunity and phagocytotic pathways in presymptomatic SOD1-G93A mice expressing IL-10 + M3 or IL-10 alone. Further, while IL-10 expression increased microglial burden, the IL-10 + M3 group showed lower microglial burden, suggesting that M3 can successfully lower microgliosis before disease onset. Our data demonstrates that over-expression of an anti-inflammatory cytokine and a decoy chemokine receptor can modulate inflammatory processes in SOD1-G93A mice, modestly delaying the age to paralysis. This suggests that multiple inflammatory pathways can be targeted simultaneously in neurodegenerative disease and supports consideration of adapting these approaches to treatment of ALS and related disorders.


2020 ◽  
Author(s):  
Weisong Duan ◽  
Le Yi ◽  
Yunyun Tian ◽  
Huai-peng Huang ◽  
Zhongyao Li ◽  
...  

Abstract Background: TBK1 haploinsufficiency has been shown to cause both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD); however, the mechanism is unclear. Methods: A myeloid Tbk1 knockout mice (Tbk1-LKO mice) was established. Motor functional and pathological analyses were also performed. The p-TBK1 was tested by flow cytometry in the ALS animal model and patients. The inflammatory proteins and mRNA was analyzed by Western blot and RT-PCR.Results: We found that the latency to fall in seven-month-old Tbk1-LKO mice was significantly reduced on evaluation on two consecutive days. Overall, 25.6% of Tbk1-LKO mice presented paralysis symptoms and signs along with a loosened myelin sheath and axon degeneration at 14-16 months of age. Furthermore, Tbk1 deficiency in myeloid cells induced inflammatory cell infiltration and dysbacteriosis in the digestive tract. Additionally, p-Tbk1 content was reduced by 29.5% and 14.8% in monocytes of definite ALS and probable ALS patients and decreased by 27.6% and 45.5% in the monocytes and microglia of ALS animals, respectively. PEI-mannose-TBK1 or PEI-mannose-SaCas9-sgRNA for deleting mutant SOD1 in macrophages significantly delayed disease onset and prolonged survival in the ALS mouse model. Conclusions: These data suggest that inflammatory monocyte and macrophage infiltration and impaired innate immune defense are contributing factors to ALS and FTD.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Qiuli Zhang ◽  
Cuiping Mao ◽  
Jiaoting Jin ◽  
Chen Niu ◽  
Lijun Bai ◽  
...  

Conflicting findings have been reported regarding the lateralized brain abnormality in patients with amyotrophic lateral sclerosis (ALS). In this study, we aimed to investigate the probable lateralization of gray matter (GM) atrophy in ALS patients. We focused on the relationship between the asymmetry in decreased GM volume and the side of disease onset in patients with limb-onset. Structural imaging evaluation of normalized atrophy (SIENAX) and voxel-based morphometry (VBM) were used to assess differences in global and local brain regions in patients with heterogeneous body onset and subgroups with different side of limb-onset. We found global brain atrophy and GM losses in the frontal and parietal areas in each patient group as well as left predominant GM losses in the total cohort. The intriguing findings in subgroup analyses demonstrated that the motor cortex in the contralateral hemisphere of the initially involved limb was most affected. We also found that regional brain atrophy was related to disease progression rate. Our observations suggested that side of limb-onset can predict laterality of GM loss in ALS patients and disease progression correlates with the extent of cortical abnormality.


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