BACKGROUND: Juvenile amyotrophic lateral sclerosis (JALS) is an uncommon form of amyotrophic lateral sclerosis whose age at onset (AAO) is defined as prior to 25 years. FUS mutations are the most common cause of JALS. SPTLC1 was recently identified as a disease-causative gene for JALS, which has rarely been reported in Asian populations. Little is known regarding the difference in clinical features between JALS patients carrying FUS and SPTLC1 mutations. This study aimed to screen mutations in JALS patients and to compare the clinical features between JALS patients with FUS and SPTLC1 mutations. METHODS: Sixteen JALS patients were enrolled, including three newly recruited patients between July 2015 and August 2018 from the Second Affiliated Hospital, Zhejiang University School of Medicine. Mutations were screened by whole-exome sequencing. In addition, clinical features such as AAO, onset site and disease duration were extracted and compared between JALS patients carrying FUS and SPTLC1 mutations through a literature review. RESULTS: A novel and de novo SPTLC1 mutation (c.58G>A, p.A20T) was identified in a sporadic patient. Among 16 JALS patients, 7/16 carried FUS mutations and 5/16 carried respective SPTLC1 , SETX , NEFH , DCTN1 , and TARDBP mutations. Compared with FUS mutation patients, those with SPTLC1 mutations had an earlier AAO (7.9 ± 4.6 years vs. 18.1 ± 3.9 years, P  < 0.01), much longer disease duration (512.0 [416.7-607.3] months vs. 33.4 [21.6-45.1] months, P  < 0.01), and no onset of bulbar. CONCLUSION Our findings expand the genetic and phenotypic spectrum of JALS and help to better understand the genotype-phenotype correlation of JALS.
Humans ; Amyotrophic Lateral Sclerosis/genetics* ; DNA Helicases/genetics* ; Genetic Association Studies ; Multifunctional Enzymes/genetics* ; Mutation/genetics* ; RNA Helicases/genetics* ; RNA-Binding Protein FUS/genetics* ; Serine C-Palmitoyltransferase/genetics* ; Child, Preschool ; Child ; Adolescent ; Young Adult

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting both upper and lower motor neurons in the brain and spinal cord. One important aspect of ALS pathogenesis is superoxide dismutase 1 (SOD1) mutant-mediated mitochondrial toxicity, leading to apoptosis in neurons. This study aimed to evaluate the neural protective synergistic effects of ginsenosides Rg1 (G-Rg1) and conditioned medium (CM) on a mutational SOD1 cell model, and to explore the underlying mechanisms. We found that the contents of nerve growth factor, glial cell line-derived neurotrophic factor, and brain-derived neurotrophic factor significantly increased in CM after human umbilical cord mesenchymal stem cells (hUCMSCs) were exposed to neuron differentiation reagents for seven days. CM or G-Rg1 decreased the apoptotic rate of SOD1^G93A-NSC34 cells to a certain extent, but their combination brought about the least apoptosis, compared with CM or G-Rg1 alone. Further research showed that the anti-apoptotic protein Bcl-2 was upregulated in all the treatment groups. Proteins associated with mitochondrial apoptotic pathways, such as Bax, caspase 9 (Cas-9), and cytochrome c (Cyt c), were downregulated. Furthermore, CM or G-Rg1 also inhibited the activation of the nuclear factor-kappa B (NF-κB) signaling pathway by reducing the phosphorylation of p65 and IκBα. CM/G-Rg1 or their combination also reduced the apoptotic rate induced by betulinic acid (BetA), an agonist of the NF-κB signaling pathway. In summary, the combination of CM and G-Rg1 effectively reduced the apoptosis of SOD1^G93A-NSC34 cells through suppressing the NF-κB/Bcl-2 signaling pathway (Fig. 1 is a graphical representation of the abstract).
Humans ; NF-kappa B/metabolism* ; Ginsenosides/pharmacology* ; Amyotrophic Lateral Sclerosis/genetics* ; Culture Media, Conditioned/pharmacology* ; Superoxide Dismutase-1 ; Neurodegenerative Diseases ; Neurons/metabolism* ; Apoptosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease which is associated with genetic and environmental factors, though the pathogenesis is still unclear and there is also a lack of effective treatment. With the rapid advance of genetic testing techniques, over 30 genes have been associated with the disease. Some ALS patients harboring genetic variants may present unique clinical characteristics and particular mode of inheritance, but the correlation between genotype and phenotype is still not very clear. Studies have shown that research on the pathogenic genes of ALS is important for the diagnosis and selection of potential drug targets. Here the pathogenic genes of ALS, in particular the newly discovered genes, and their underlying mechanisms are reviewed. The necessity of genetic testing for ALS patients is also stressed.
Amyotrophic Lateral Sclerosis/genetics* ; Genetic Testing ; Genotype ; Humans ; Neurodegenerative Diseases/genetics* ; Phenotype

Humans ; Amyotrophic Lateral Sclerosis/genetics* ; Genetic Predisposition to Disease ; Polymorphism, Single Nucleotide

Animal models are essential for investigating the pathogenesis and developing the treatment of human diseases. Identification of genetic mutations responsible for neurodegenerative diseases has enabled the creation of a large number of small animal models that mimic genetic defects found in the affected individuals. Of the current animal models, rodents with genetic modifications are the most commonly used animal models and provided important insights into pathogenesis. However, most of genetically modified rodent models lack overt neurodegeneration, imposing challenges and obstacles in utilizing them to rigorously test the therapeutic effects on neurodegeneration. Recent studies that used CRISPR/Cas9-targeted large animal (pigs and monkeys) have uncovered important pathological events that resemble neurodegeneration in the patient's brain but could not be produced in small animal models. Here we highlight the unique nature of large animals to model neurodegenerative diseases as well as the limitations and challenges in establishing large animal models of neurodegenerative diseases, with focus on Huntington disease, Amyotrophic lateral sclerosis, and Parkinson diseases. We also discuss how to use the important pathogenic insights from large animal models to make rodent models more capable of recapitulating important pathological features of neurodegenerative diseases.
Amyotrophic Lateral Sclerosis/genetics* ; Animals ; Brain/pathology* ; Disease Models, Animal ; Gene Editing ; Neurodegenerative Diseases/pathology* ; Swine

The nucleocapsid (N) protein of SARS-CoV-2 has been reported to have a high ability of liquid-liquid phase separation, which enables its incorporation into stress granules (SGs) of host cells. However, whether SG invasion by N protein occurs in the scenario of SARS-CoV-2 infection is unknow, neither do we know its consequence. Here, we used SARS-CoV-2 to infect mammalian cells and observed the incorporation of N protein into SGs, which resulted in markedly impaired self-disassembly but stimulated cell cellular clearance of SGs. NMR experiments further showed that N protein binds to the SG-related amyloid proteins via non-specific transient interactions, which not only expedites the phase transition of these proteins to aberrant amyloid aggregation in vitro, but also promotes the aggregation of FUS with ALS-associated P525L mutation in cells. In addition, we found that ACE2 is not necessary for the infection of SARS-CoV-2 to mammalian cells. Our work indicates that SARS-CoV-2 infection can impair the disassembly of host SGs and promote the aggregation of SG-related amyloid proteins, which may lead to an increased risk of neurodegeneration.
Amyloidogenic Proteins/metabolism* ; Amyotrophic Lateral Sclerosis/genetics* ; Animals ; COVID-19 ; Cytoplasmic Granules/metabolism* ; Mammals ; SARS-CoV-2 ; Stress Granules

OBJECTIVE: To analyze the distribution characteristics of hereditary peripheral neuropathy (HPN) pathogenic genes in Chinese Han population, and to explore the potential pathogenesis and treatment prospects of HPN and related diseases. METHODS: Six hundred and fifty-six index patients with HPN were enrolled in Peking University Third Hospital and China-Japan Friendship Hospital from January 2007 to May 2022. The PMP22 duplication and deletion mutations were screened and validated by multiplex ligation probe amplification technique. The next-generation sequencing gene panel or whole exome sequencing was used, and the suspected genes were validated by Sanger sequencing. RESULTS: Charcot-Marie-Tooth (CMT) accounted for 74.3% (495/666) of the patients with HPN, of whom 69.1% (342/495) were genetically confirmed. The most common genes of CMT were PMP22 duplication, MFN2 and GJB1 mutations, which accounted for 71.3% (244/342) of the patients with genetically confirmed CMT. Hereditary motor neuropathy (HMN) accounted for 16.1% (107/666) of HPN, and 43% (46/107) of HPN was genetically confirmed. The most common genes of HMN were HSPB1, aminoacyl tRNA synthetases and SORD mutations, which accounted for 56.5% (26/46) of the patients with genetically confirmed HMN. Most genes associated with HMN could cause different phenotypes. HMN and CMT shared many genes (e.g. HSPB1, GARS, IGHMBP2). Some genes associated with dHMN-plus shared genes associated with amyotrophic lateral sclerosis (KIF5A, FIG4, DCTN1, SETX, VRK1), hereditary spastic paraplegia (KIF5A, ZFYVE26, BSCL2) and spinal muscular atrophy (MORC2, IGHMBP, DNAJB2), suggesting that HMN was a continuum rather than a distinct entity. Hereditary sensor and autosomal neuropathy (HSAN) accounted for a small proportion of 2.6% (17/666) in HPN. The most common pathogenic gene was SPTLC1 mutation. TTR was the main gene causing hereditary amyloid peripheral neuropathy. The most common types of gene mutations were p.A117S and p.V50M. The symptoms were characterized by late-onset and prominent autonomic nerve involvement. CONCLUSION CMT and HMN are the most common diseases of HPN. There is a large overlap between HMN and motor-CMT2 pathogenic genes, and some HMN pathogenic genes overlap with amyotrophic lateral sclerosis, hereditary spastic hemiplegia and spinal muscular atrophy, suggesting that there may be a potential common pathogenic pathway between different diseases.
Amyotrophic Lateral Sclerosis ; Charcot-Marie-Tooth Disease/genetics* ; DNA Helicases/genetics* ; DNA-Binding Proteins/genetics* ; Flavoproteins ; HSP40 Heat-Shock Proteins ; Humans ; Intracellular Signaling Peptides and Proteins/genetics* ; Kinesins ; Ligases/genetics* ; Molecular Chaperones ; Multifunctional Enzymes ; Muscular Atrophy, Spinal/genetics* ; Mutation ; Phosphoric Monoester Hydrolases ; Protein Serine-Threonine Kinases ; RNA Helicases/genetics* ; RNA, Transfer ; Transcription Factors/genetics*

OBJECTIVE: To explore the genetic basis for a Chinese patient with amyotrophic lateral sclerosis (ALS). METHODS: Peripheral blood samples were collected from the patient and his parents for the extraction of genomic DNA. Genetic variant was identified by whole exome sequencing. Candidate variant was verified by Sanger sequencing of his parents and healthy controls. RESULTS: The patient was found to harbor a heterozygous c.420C>G (p.Asn140Lys) variant of the SOD1 gene. The same variant was not detected in his parents and 100 healthy controls. The variant has not been included in HGMD, dbSNP and other databases. CONCLUSION The c.420C>G variant of the SOD1 gene may underlie the ALS in this patient. Above finding has enriched the spectrum of SOD1 gene variants.
Amyotrophic Lateral Sclerosis/genetics* ; China ; Heterozygote ; Humans ; Superoxide Dismutase-1/genetics* ; Whole Exome Sequencing

Amyotrophic lateral sclerosis (ALS) is a relentless, progressive, and presently incurable neurodegenerative disease. Its drug development has been hampered by the lack of effective biomarkers for early diagnosis, progression and prognosis. Recently, significant progress has been made for the identification of body fluid biomarkers for ALS, which conferred both theoretical and practical feasibility for the early diagnosis and progression monitoring. Meanwhile, it also facilitated identification of genes and/or pathways for the pathogenesis of ALS. This review summarized biomarkers identified from cerebrospinal fluid, blood and urine of ALS patients and their clinical implications.
Amyotrophic Lateral Sclerosis/genetics* ; Biomarkers ; Humans ; Neurodegenerative Diseases ; Prognosis

OBJECTIVE: To explore the association between rare HSPB1 variants and amyotrophic lateral sclerosis (ALS). METHODS: We performed next-generation sequencing for 166 Chinese ALS patients to screen for possible pathogenic rare variants of HSPB1. The control individuals were obtained from 1000 Genome Project and an in-house whole-exome sequencing database. The Sequence Kernel Association Test (SKAT) and the SKAT-optimal test (SKAT-O) were used to identify the association between rare HSPB1 variants and ALS. RESULTS: We identified 3 possible pathogenic rare variants of HSPB1 (all were missenses), including c.379C>T (p.R127W), c.446A>C (p.D149A) and c.451A>C (p.T151P). Compared with 1000 Genome Project, SKAT p=3.61×10 CONCLUSIONS Rare variants of HSPB1 are probably associated with the pathogenesis of ALS.
Amyotrophic Lateral Sclerosis/genetics* ; Asian Continental Ancestry Group ; Heat-Shock Proteins ; Heterozygote ; High-Throughput Nucleotide Sequencing ; Humans ; Molecular Chaperones ; Phenotype