Amyotrophic lateral sclerosis（ALS）is a devastating neurodegenerative disorder characterized by loss of upper and lower motor neurons.Different mechanisms contribute to the disease initiation and progression,includin...Amyotrophic lateral sclerosis（ALS）is a devastating neurodegenerative disorder characterized by loss of upper and lower motor neurons.Different mechanisms contribute to the disease initiation and progression,including mitochondrial dysfunction which has been proposed to be a central determinant in ALS pathogenesis.Indeed,while mitochondrial defects have been mainly described in ALS-linked SOD1 mutants,it is now well established that mitochondria become also dysfunctional in other ALS conditions.In such context,the mitochondrial quality control system allows to restore normal functioning of mitochondria and to prevent cell death,by both eliminating and replacing damaged mitochondrial components or by degrading the entire organelle through mitophagy.Recent evidence shows that ALS-related genes interfere with the mitochondrial quality control system.This review highlights how ineffective mitochondrial quality control may render motor neurons defenseless towards the accumulating mitochondrial damage in ALS.展开更多
Amyotrophic lateral sclerosis is a very disabling disease due to the degeneration of motor neurons.Symptoms include muscle weakness and atrophy,spasticity,and progressive paralysis.Currently,there is no treatment to r...Amyotrophic lateral sclerosis is a very disabling disease due to the degeneration of motor neurons.Symptoms include muscle weakness and atrophy,spasticity,and progressive paralysis.Currently,there is no treatment to reverse damage to motor neurons and cure amyotrophic lateral sclerosis.The only two treatments actually approved,riluzole and edaravone,have shown mitigated beneficial effects.The difficulty to find a cure lies in the complexity and multifaceted pattern of amyotrophic lateral sclerosis pathogenesis.Among mechanisms,abnormal RNA metabolism,nucleocytoplasmic transport defects,accumulation of unfolded protein,and mitochondrial dysfunction would in fine induce oxidative damage and vice versa.A potent therapeutic strategy will be to find molecules that break this vicious circle.Sharpening the nuclear factor erythroid-2 related factor 2 signaling may fulfill this objective since nuclear factor erythroid-2 related factor 2 has a multitarget profile controlling antioxidant defense,mitochondrial functioning,and inflammation.We here discuss the interest of developing nuclear factor erythroid-2 related factor 2-based therapy in regard to the pathophysiological mechanisms and we provide a general overview of the attempted clinical assays in amyotrophic lateral sclerosis.展开更多
Diagnostic C9orf72 hexanucleotide repeat expansions(C9-HRE)is essential for the early and accurate diagnosis of amyotrophic lateral sclerosis(ALS)and will provide support for the prognosis and gene therapy of ALS.In t...Diagnostic C9orf72 hexanucleotide repeat expansions(C9-HRE)is essential for the early and accurate diagnosis of amyotrophic lateral sclerosis(ALS)and will provide support for the prognosis and gene therapy of ALS.In the present study,by combining catalytic hairpin assembly(CHA)with Mycobacterium smegmatis porin A(MspA)nanopore,a new nanopore-based strategy for the detection of C9-HRE was reported.Less than 30 repeats of C9-HRE could be detected via this method,and the results have the potential to help distinguish between patients and healthy individuals.Moreover,the method demonstrated its great specificity for C9-HRE by identifying other repeat expansions.Given the high selectivity,this approach had been successfully used to detect C9-HRE in cell and blood samples with high accuracy.This detection strategy is user-friendly and has a strong anti-interference ability,thus providing a powerful tool for clinical diagnosis.展开更多
Amyotrophic lateral sclerosis is a neurodegenerative disease,and the molecular mechanism underlying its pathology remains poorly understood.However,inflammation is known to play an important role in the development of...Amyotrophic lateral sclerosis is a neurodegenerative disease,and the molecular mechanism underlying its pathology remains poorly understood.However,inflammation is known to play an important role in the development of this condition.To identify driver genes that affect the inflammatory response in amyotrophic lateral sclerosis,as well as potential treatment targets,it is crucial to analyze brain tissue samples from patients with both sporadic amyotrophic lateral sclerosis and C9orf72-related amyotrophic lateral sclerosis.Therefore,in this study we used a network-driven gene analysis tool,NetBID2.0,which is based on SJARACNe,a scalable algorithm for the reconstruction of accurate cellular networks,to experimentally analyze sequencing data from patients with sporadic amyotrophic lateral sclerosis.The results showed that the OSMR gene is pathogenic in amyotrophic lateral sclerosis and participates in the progression of amyotrophic lateral sclerosis by mediating the neuroinflammatory response.Furthermore,there were differences in OSMR activity and expression between patients with sporadic amyotrophic lateral sclerosis and those with C9orf72-related amyotrophic lateral sclerosis.These findings suggest that OSMR may be a diagnostic and prognostic marker for amyotrophic lateral sclerosis.展开更多
Growing evidences indicate that dysfunction of autophagy contributes to the disease pathogenesis of amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD),two neurodegenerative disorders.The GGGGCC·GG...Growing evidences indicate that dysfunction of autophagy contributes to the disease pathogenesis of amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD),two neurodegenerative disorders.The GGGGCC·GGCCCC repeat RNA expansion in chromosome 9 open reading frame 72(C9orf72)is the most genetic cause of both ALS and FTD.According to the previous studies,GGGGCC·GGCCCC repeat undergoes the unconventional repeat-associated non-ATG translation,which produces dipeptide repeat(DPR)proteins.Although there is a growing understanding that C9orf72 DPRs have a strong ability to harm neurons and induce C9orf72-linked ALS/FTD,whether these DPRs can affect autophagy remains unclear.In the present study,we find that poly-GR and poly-PR,two arginine-containing DPRs which display the most cytotoxic properties according to the previous studies,strongly inhibit starvation-induced autophagy.Moreover,our data indicate that arginine-rich DPRs enhance the interaction between BCL2 and BECN1/Beclin 1 by inhibiting BCL2 phosphorylation,therefore they can impair autophagic clearance of neurodegenerative disease-associated protein aggregates under starvation condition in cells.Importantly,our study not only highlights the role of C9orf72 DPR in autophagy dysfunction,but also provides novel insight that pharmacological intervention of autophagy using SW063058,a small molecule compound that can disrupt the interaction between BECN1 and BCL2,may reduce C9orf72 DPR-induced neurotoxicity.展开更多
GGGGCC repeat expansions in the C9 ORF72 gene are the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia(c9 ALS/FTD). It has been reported that hexanucleotide repeat expansions in C9 ORF72 ...GGGGCC repeat expansions in the C9 ORF72 gene are the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia(c9 ALS/FTD). It has been reported that hexanucleotide repeat expansions in C9 ORF72 produce five dipeptide repeat(DPR) proteins by an unconventional repeat-associated non-ATG(RAN)translation. Within the five DPR proteins, poly-PR and poly-GR that contain arginine are more toxic than the other DPRs(poly-GA, poly-GP, and poly-PA). Here, we demonstrated that poly-PR peptides transferred into cells by endocytosis in a clathrin-dependent manner, leading to endoplasmic reticulum stress and cell death. In SH-SY5 Y cells and primary cortical neurons, poly-PR activated JUN amino-terminal kinase(JNK) and increased the levels of p53 and Bax. The uptake of poly-PR peptides by cells was significantly inhibited by knockdown of clathrin or by chlorpromazine, an inhibitor that blocks clathrin-mediated endocytosis. Inhibition of clathrin-dependent endocytosis by chlorpromazine significantly blocked the transfer of poly-PR peptides into cells, and attenuated poly-PRinduced JNK activation and cell death. Our data revealed that the uptake of poly-PR undergoes clathrin-dependentendocytosis and blockade of this process prevents the toxic effects of synthetic poly-PR peptides.展开更多
Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS...Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS,possibly caused by expanded GGGGCC repeats(G4C2r)in the C9ORF72 gene],of which the molecular mechanisms remain unclear.Here,we demonstrated that lowering the Drosophila homologue of tau protein(dtau)significantly rescued in vivo neurodegeneration,motor performance impairments,and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r.Expression of human tau(htau4 R)restored the disease-related phenotypes that had been mitigated by the loss of dtau,suggesting an evolutionarily-conserved role of tau in neurodegeneration.We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome-lysosome fusion,possibly due to lowering the level of BAG3,a regulator of autophagy and tau.Taken together,our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism.Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.展开更多
文摘Amyotrophic lateral sclerosis（ALS）is a devastating neurodegenerative disorder characterized by loss of upper and lower motor neurons.Different mechanisms contribute to the disease initiation and progression,including mitochondrial dysfunction which has been proposed to be a central determinant in ALS pathogenesis.Indeed,while mitochondrial defects have been mainly described in ALS-linked SOD1 mutants,it is now well established that mitochondria become also dysfunctional in other ALS conditions.In such context,the mitochondrial quality control system allows to restore normal functioning of mitochondria and to prevent cell death,by both eliminating and replacing damaged mitochondrial components or by degrading the entire organelle through mitophagy.Recent evidence shows that ALS-related genes interfere with the mitochondrial quality control system.This review highlights how ineffective mitochondrial quality control may render motor neurons defenseless towards the accumulating mitochondrial damage in ALS.
基金supported by a grant from the Association Française contre les Myopathies(AFM Téléthongrant 23667,to JCL).
文摘Amyotrophic lateral sclerosis is a very disabling disease due to the degeneration of motor neurons.Symptoms include muscle weakness and atrophy,spasticity,and progressive paralysis.Currently,there is no treatment to reverse damage to motor neurons and cure amyotrophic lateral sclerosis.The only two treatments actually approved,riluzole and edaravone,have shown mitigated beneficial effects.The difficulty to find a cure lies in the complexity and multifaceted pattern of amyotrophic lateral sclerosis pathogenesis.Among mechanisms,abnormal RNA metabolism,nucleocytoplasmic transport defects,accumulation of unfolded protein,and mitochondrial dysfunction would in fine induce oxidative damage and vice versa.A potent therapeutic strategy will be to find molecules that break this vicious circle.Sharpening the nuclear factor erythroid-2 related factor 2 signaling may fulfill this objective since nuclear factor erythroid-2 related factor 2 has a multitarget profile controlling antioxidant defense,mitochondrial functioning,and inflammation.We here discuss the interest of developing nuclear factor erythroid-2 related factor 2-based therapy in regard to the pathophysiological mechanisms and we provide a general overview of the attempted clinical assays in amyotrophic lateral sclerosis.
基金supported by a grant from the National Key Research and Development Program of China(No.2022YFB3205600)National Natural Science Foundation of China(No.82004341)+3 种基金China Postdoctoral Science Foundation(No.2022M712286)Sichuan Science and Technology Program(No.2020JDTD0022)Sichuan Administration of Traditional Chinese Medicine(No.2023MS078)Sichuan University Postdoctoral Interdisciplinary Innovation Fund(No.JCXK2225)。
文摘Diagnostic C9orf72 hexanucleotide repeat expansions(C9-HRE)is essential for the early and accurate diagnosis of amyotrophic lateral sclerosis(ALS)and will provide support for the prognosis and gene therapy of ALS.In the present study,by combining catalytic hairpin assembly(CHA)with Mycobacterium smegmatis porin A(MspA)nanopore,a new nanopore-based strategy for the detection of C9-HRE was reported.Less than 30 repeats of C9-HRE could be detected via this method,and the results have the potential to help distinguish between patients and healthy individuals.Moreover,the method demonstrated its great specificity for C9-HRE by identifying other repeat expansions.Given the high selectivity,this approach had been successfully used to detect C9-HRE in cell and blood samples with high accuracy.This detection strategy is user-friendly and has a strong anti-interference ability,thus providing a powerful tool for clinical diagnosis.
基金supported by the National Natural Science Foundation of China,Nos.30560042,81160161,81360198,82160255a grant from Department of Education of Jiangxi Province,Nos.GJJ13198,GJJ170021+1 种基金Jiangxi Provincial Department of Science and Technology,Nos.[2014]-47,20142BBG70062,20171BAB215022,20192BAB205043Science and Technology Plan of Jiangxi Commission of Health,Nos.202210002,202310119(all to RX).
文摘Amyotrophic lateral sclerosis is a neurodegenerative disease,and the molecular mechanism underlying its pathology remains poorly understood.However,inflammation is known to play an important role in the development of this condition.To identify driver genes that affect the inflammatory response in amyotrophic lateral sclerosis,as well as potential treatment targets,it is crucial to analyze brain tissue samples from patients with both sporadic amyotrophic lateral sclerosis and C9orf72-related amyotrophic lateral sclerosis.Therefore,in this study we used a network-driven gene analysis tool,NetBID2.0,which is based on SJARACNe,a scalable algorithm for the reconstruction of accurate cellular networks,to experimentally analyze sequencing data from patients with sporadic amyotrophic lateral sclerosis.The results showed that the OSMR gene is pathogenic in amyotrophic lateral sclerosis and participates in the progression of amyotrophic lateral sclerosis by mediating the neuroinflammatory response.Furthermore,there were differences in OSMR activity and expression between patients with sporadic amyotrophic lateral sclerosis and those with C9orf72-related amyotrophic lateral sclerosis.These findings suggest that OSMR may be a diagnostic and prognostic marker for amyotrophic lateral sclerosis.
基金This work was supported by the National Natural Science Foundation of China(Nos.82022022,32371018 and 82071274)a Project Funded by Jiangsu Key Laboratory of Neuropsychiatric Diseases(BM2013003,China)+4 种基金a Key Project of Natural Science Foundation of Jiangsu Provincial Higher Education Institutions(23KJA310005,China)a Project Funded by the Interdisciplinary Basic Frontier Innovation Program of Suzhou Medical College of Soochow University(MP13202823,China)a Project Funded by the Suzhou International Joint Laboratory for Diagnosis and Treatment of Brain Diseases,and a Project Funded by the Priority Academic Program Development of the Jiangsu Higher Education Institutes(PAPD).J.H.M.P.was supported Science Foundation Ireland(17/COEN/3474,17/JPND/3455)Q.M.is a recipient of an RCSI International StAR Ph.D.scholarship.N.L.was supported by the Postgraduate Research&Practice Innovation Program of Jiangsu Province.K.Y.T.,was supported by the financial support from the Science and Technology Development Fund,Macao SAR(File no.0062/2021/A,China)University of Macao(File no.MYRG2022-00171-FHS,China).
文摘Growing evidences indicate that dysfunction of autophagy contributes to the disease pathogenesis of amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD),two neurodegenerative disorders.The GGGGCC·GGCCCC repeat RNA expansion in chromosome 9 open reading frame 72(C9orf72)is the most genetic cause of both ALS and FTD.According to the previous studies,GGGGCC·GGCCCC repeat undergoes the unconventional repeat-associated non-ATG translation,which produces dipeptide repeat(DPR)proteins.Although there is a growing understanding that C9orf72 DPRs have a strong ability to harm neurons and induce C9orf72-linked ALS/FTD,whether these DPRs can affect autophagy remains unclear.In the present study,we find that poly-GR and poly-PR,two arginine-containing DPRs which display the most cytotoxic properties according to the previous studies,strongly inhibit starvation-induced autophagy.Moreover,our data indicate that arginine-rich DPRs enhance the interaction between BCL2 and BECN1/Beclin 1 by inhibiting BCL2 phosphorylation,therefore they can impair autophagic clearance of neurodegenerative disease-associated protein aggregates under starvation condition in cells.Importantly,our study not only highlights the role of C9orf72 DPR in autophagy dysfunction,but also provides novel insight that pharmacological intervention of autophagy using SW063058,a small molecule compound that can disrupt the interaction between BECN1 and BCL2,may reduce C9orf72 DPR-induced neurotoxicity.
基金supported by the National Natural Science Foundation of China (81761148024 and 31871023)the National Key Scientific R&D Program of China (2016YFC1306000)+1 种基金Suzhou Clinical Research Center of Neurological Disease (Szzx201503)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions, China
文摘GGGGCC repeat expansions in the C9 ORF72 gene are the most common cause of amyotrophic lateral sclerosis and frontotemporal dementia(c9 ALS/FTD). It has been reported that hexanucleotide repeat expansions in C9 ORF72 produce five dipeptide repeat(DPR) proteins by an unconventional repeat-associated non-ATG(RAN)translation. Within the five DPR proteins, poly-PR and poly-GR that contain arginine are more toxic than the other DPRs(poly-GA, poly-GP, and poly-PA). Here, we demonstrated that poly-PR peptides transferred into cells by endocytosis in a clathrin-dependent manner, leading to endoplasmic reticulum stress and cell death. In SH-SY5 Y cells and primary cortical neurons, poly-PR activated JUN amino-terminal kinase(JNK) and increased the levels of p53 and Bax. The uptake of poly-PR peptides by cells was significantly inhibited by knockdown of clathrin or by chlorpromazine, an inhibitor that blocks clathrin-mediated endocytosis. Inhibition of clathrin-dependent endocytosis by chlorpromazine significantly blocked the transfer of poly-PR peptides into cells, and attenuated poly-PRinduced JNK activation and cell death. Our data revealed that the uptake of poly-PR undergoes clathrin-dependentendocytosis and blockade of this process prevents the toxic effects of synthetic poly-PR peptides.
基金the National Natural Science Foundation of China(81925012 and 31961130379)a Newton Advanced Fellowship(NAF_R1_191045)。
文摘Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS,possibly caused by expanded GGGGCC repeats(G4C2r)in the C9ORF72 gene],of which the molecular mechanisms remain unclear.Here,we demonstrated that lowering the Drosophila homologue of tau protein(dtau)significantly rescued in vivo neurodegeneration,motor performance impairments,and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r.Expression of human tau(htau4 R)restored the disease-related phenotypes that had been mitigated by the loss of dtau,suggesting an evolutionarily-conserved role of tau in neurodegeneration.We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome-lysosome fusion,possibly due to lowering the level of BAG3,a regulator of autophagy and tau.Taken together,our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism.Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.
