ABSTRACT
The Labours of Hercules, written by Agatha Christie, contains twelve short stories, with 'atropine' playing a crucial role in the seventh story, The Cretan Bull (1939). Atropine easily crosses the blood-brain barrier (BBB), leading to central nervous system (CNS) side effects such as delirium, hallucinations, disorientation, memory problems, coma or stupor, and convulsive seizures when overdosed. In this episode, a concentrated form of atropine obtained from prescribed eye drops was misused to induce a hereditary incurable neurodegenerative disorder, similar to Huntington's Chorea, in the client's fiancée. However, Mr. Poirot discerned this by careful examination of his symptoms and resolved the case.
Subject(s)
Atropa belladonna , Atropine , Male , Animals , Cattle , Humans , Atropine/therapeutic use , Seizures , Hallucinations , Blood-Brain BarrierABSTRACT
A 74-year-old Japanese woman, who had been previously diagnosed as ocular myasthenia gravis (MG), presented to our hospital complaining of dropped head and increased fatiguability while eating. The edrophonium test was positive and decremental response was recorded on repetitive nerve stimulation. Her clinical presentation was compatible with generalized MG, and anti-AChR, Kv1.4 and titin antibodies turned out positive. Contrast enhanced CT scan showed no tumorous lesion such as thymoma. We initiated her treatment with a minimum dose of oral prednisolone. However, her condition got worse even after intravenous immune globulin and experienced myasthenic crisis twice, the former of which led to cardiopulmonary arrest. As she did not respond to traditional treatments, we determined to perform extended thymectomy. The histopathology showed atrophic change but her condition rapidly improved in several days after the operation, and soon she was weaned off the ventilator. Shortly thereafter her symptoms disappeared, followed by the titers of the antibodies above found all markedly decreased. It remains unclear how the atrophic thymus acted on the pathogenesis of refractory generalized MG.
Subject(s)
Myasthenia Gravis , Thymoma , Thymus Neoplasms , Humans , Female , Aged , Connectin , Thymectomy , Myasthenia Gravis/therapyABSTRACT
Apathy is frequently observed in idiopathic normal pressure hydrocephalus (iNPH) and worsens cognitive impairment and gait disturbance. In this study, we evaluated the regions associated with apathy in iNPH using statistical imaging analysis on the whole brain, both in terms of cerebral blood flow and gray matter volume. Twenty-seven patients with iNPH were assigned to two groups based on their scores on the neuropsychiatric inventory items related to apathy; 18 patients were assigned to the group with apathy (iNPH + APA) and 9 to the group without apathy (iNPH - APA). The magnetic resonance images and cerebral blood flow single-photon emission computed tomography data of the two groups were compared using statistical parametric mapping 12. The regional gray matter volume of the right precuneus was significantly larger in the iNPH + APA group than in the iNPH - APA group, but the regional cerebral blood flow in any region of the brain was not significantly different between the two groups. These results suggested that the larger gray matter volume, which is thought to reflect gray matter compression, in the precuneus might be involved in apathy in iNPH.
Subject(s)
Apathy , Data Compression , Hydrocephalus, Normal Pressure , Humans , Pilot Projects , Hydrocephalus, Normal Pressure/diagnostic imaging , Parietal Lobe/diagnostic imagingABSTRACT
Importance: The effectiveness of currently approved drugs for amyotrophic lateral sclerosis (ALS) is restricted; there is a need to develop further treatments. Initial studies have shown ultrahigh-dose methylcobalamin to be a promising agent. Objective: To validate the efficacy and safety of ultrahigh-dose methylcobalamin for patients with ALS enrolled within 1 year of onset. Design, Setting, and Participants: This was a multicenter, placebo-controlled, double-blind, randomized phase 3 clinical trial with a 12-week observation and 16-week randomized period, conducted from October 17, 2017, to September 30, 2019. Patients were recruited from 25 neurology centers in Japan; those with ALS diagnosed within 1 year of onset by the updated Awaji criteria were initially enrolled. Of those, patients fulfilling the following criteria after 12-week observation were eligible for randomization: 1- or 2-point decrease in the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) total score, a percent forced vital capacity greater than 60%, no history of noninvasive respiratory support and tracheostomy, and being ambulatory. The target participant number was 64 in both the methylcobalamin and placebo groups. Patients were randomly assigned through an electronic web-response system to methylcobalamin or placebo. Interventions: Intramuscular injection of methylcobalamin (50-mg dose) or placebo twice weekly for 16 weeks. Main Outcomes and Measures: The primary end point was change in ALSFRS-R total score from baseline to week 16 in the full analysis set. Results: A total of 130 patients (mean [SD] age, 61.0 [11.7] years; 74 men [56.9%]) were randomly assigned to methylcobalamin or placebo (65 each). A total of 129 patients were eligible for the full analysis set, and 126 completed the double-blind stage. Of these, 124 patients proceeded to the open-label extended period. The least square means difference in ALSFRS-R total score at week 16 of the randomized period was 1.97 points greater with methylcobalamin than placebo (-2.66 vs -4.63; 95% CI, 0.44-3.50; P = .01). The incidence of adverse events was similar between the 2 groups. Conclusions and Relevance: Results of this randomized clinical trial showed that ultrahigh-dose methylcobalamin was efficacious in slowing functional decline in patients with early-stage ALS and with moderate progression rate and was safe to use during the 16-week treatment period. Trial Registration: ClinicalTrials.gov Identifier: NCT03548311.
Subject(s)
Amyotrophic Lateral Sclerosis , Amyotrophic Lateral Sclerosis/diagnosis , Amyotrophic Lateral Sclerosis/drug therapy , Double-Blind Method , Humans , Male , Middle Aged , Treatment Outcome , Vital Capacity , Vitamin B 12/analogs & derivatives , Vitamin B 12/therapeutic useABSTRACT
Idiopathic hypersomnia (IH) is a rare, heterogeneous sleep disorder characterized by excessive daytime sleepiness. In contrast to narcolepsy type 1, which is a well-defined type of central disorders of hypersomnolence, the etiology of IH is poorly understood. No susceptibility loci associated with IH have been clearly identified, despite the tendency for familial aggregation of IH. We performed a variation screening of the prepro-orexin/hypocretin and orexin receptors genes and an association study for IH in a Japanese population, with replication (598 patients and 9826 controls). We identified a rare missense variant (g.42184347T>C; p.Lys68Arg; rs537376938) in the cleavage site of prepro-orexin that was associated with IH (minor allele frequency of 1.67% in cases versus 0.32% in controls, P = 2.7 × 10-8, odds ratio = 5.36). Two forms of orexin (orexin-A and -B) are generated from cleavage of one precursor peptide, prepro-orexin. The difference in cleavage efficiency between wild-type (Gly-Lys-Arg; GKR) and mutant (Gly-Arg-Arg; GRR) peptides was examined by assays using proprotein convertase subtilisin/kexin (PCSK) type 1 and PCSK type 2. In both PCSK1 and PCSK2 assays, the cleavage efficiency of the mutant peptide was lower than that of the wild-type peptide. We also confirmed that the prepro-orexin peptides themselves transmitted less signaling through orexin receptors than mature orexin-A and orexin-B peptides. These results indicate that a subgroup of IH is associated with decreased orexin signaling, which is believed to be a hallmark of narcolepsy type 1.
ABSTRACT
BACKGROUND: Swallowing dysfunction is related to major cause of adverse events and an indicator of shorter survival among patients with neuromuscular disorders (NMD). It is critical to assess the swallowing function during disease progression, however, there are limited tools that can easily evaluate swallowing function without using videofluoroscopic or videoendoscopic examination. Here, we evaluated the longitudinal changes in tongue thickness (TT) and maximum tongue pressure (MTP) among patients with amyotrophic lateral sclerosis (ALS), myotonic dystrophy type 1 (DM1), and Duchenne muscular dystrophy (DMD). METHODS: Between 2010 and 2020, TT and MTP were measured from 21 ALS, 30 DM1, and 14 DMD patients (mean ages of 66.9, 44.5, and 21.4 years, respectively) at intervals of more than half a year. TT was measured, by ultrasonography, as the distance from the mylohyoid muscle raphe to the tongue dorsum, and MTP was determined by measuring the maximum compression on a small balloon when pressing the tongue against the palate. Then we examined the relationship between these evaluations and patient background and swallowing function. RESULTS: Mean follow-up periods were 24.0 months in the ALS group, 47.2 months in the DM1group, and 61.1 months in the DMD group. The DMD group demonstrated larger first TT than the other groups, while the DM1 group had lower first MTP than the ALS group. The ALS group showed a greater average monthly reduction in mean TT than the DM1 group and greater monthly reductions in mean body weight (BW) and MTP than the other groups. Significant differences between the first and last BW, TT, and MTP measures were found only in the ALS group. CONCLUSIONS: This study suggests that ALS is associated with more rapid degeneration of tongue function over several years compared to DMD and DM1.
Subject(s)
Deglutition Disorders , Neuromuscular Diseases , Tongue , Amyotrophic Lateral Sclerosis/complications , Amyotrophic Lateral Sclerosis/diagnostic imaging , Deglutition , Humans , Pressure , Tongue/diagnostic imagingABSTRACT
Spastic paraplegia type 11 (SPG11) is the most common autosomal recessive hereditary spastic paraplegia with thinning of the corpus callosum. Spatacsin, a protein encoded by the SPG11 gene, is associated with autophagy. SPG11 patients show spastic paraplegia, intellectual disability, dementia, and parkinsonism. A previous neuropathological analysis of SPG11 cases reported neurodegeneration mimicking amyotrophic lateral sclerosis without transactivation response DNA-binding protein of 43 kDa (TDP-43) deposits and unique sequestosome 1 (SQSTM1)-positive neuronal inclusions. We performed a neuropathological examination of two Japanese patients with complicated spastic paraplegia with thinning of the corpus callosum from different families, and one was genetically diagnosed as having SPG11. Both cases showed diffuse atrophy of the brain and spinal cord. Depigmentation of the substantia nigra was also observed. Immunohistochemistry revealed widespread distribution of areas showing TDP-43 aggregation in the central nervous system. The TDP-43 deposits in the thalamus and substantia nigra especially resembled skein-like inclusions. Unique SQSTM1-positive neuronal inclusions, as previously reported, were widespread in the whole central nervous system as well as the dorsal root ganglia. Double-labeling immunofluorescence of the dorsal root ganglia revealed that the unique, large SQSTM1-positive cytoplasmic inclusions of the ganglion cells were labeled with lysosome-associated membrane protein 1 and lysosome-associated membrane protein 2. This is the first report showing TDP-43 pathology in SPG11. The common neuropathological findings of TDP-43-positive inclusions in both the cases imply a causal connection between the TDP-43 proteinopathy and autophagy dysfunction in SPG11.
Subject(s)
DNA-Binding Proteins , Spastic Paraplegia, Hereditary , Humans , Lysosomes , Mutation , Proteins , TDP-43 Proteinopathies , Transcriptional ActivationABSTRACT
Sialidosis is a neuropathic lysosomal storage disease caused by a deficiency in the NEU1 gene-encoding lysosomal neuraminidase and characterized by abnormal accumulation of undigested sialyl-oligoconjugates in systemic organs including brain. Although patients exhibit neurological symptoms, the underlying neuropathological mechanism remains unclear. Here, we generated induced pluripotent stem cells (iPSCs) from skin fibroblasts with sialidosis and induced the differentiation into neural progenitor cells (NPCs) and neurons. Sialidosis NPCs and neurons mimicked the disease-like phenotypes including reduced neuraminidase activity, accumulation of sialyl-oligoconjugates and lysosomal expansions. Functional analysis also revealed that sialidosis neurons displayed two distinct abnormalities, defective exocytotic glutamate release and augmented α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPAR)-mediated Ca2+ influx. These abnormalities were restored by overexpression of the wild-type NEU1 gene, demonstrating causative role of neuraminidase deficiency in functional impairments of disease neurons. Comprehensive proteomics analysis revealed the significant reduction of SNARE proteins and glycolytic enzymes in synaptosomal fraction, with downregulation of ATP production. Bypassing the glycolysis by treatment of pyruvate, which is final metabolite of glycolysis pathway, improved both the synaptsomal ATP production and the exocytotic function. We also found that upregulation of AMPAR and L-type voltage dependent Ca2+ channel (VDCC) subunits in disease neurons, with the restoration of AMPAR-mediated Ca2+ over-load by treatment of antagonists for the AMPAR and L-type VDCC. Our present study provides new insights into both the neuronal pathophysiology and potential therapeutic strategy for sialidosis.
Subject(s)
Calcium Signaling/physiology , Mucolipidoses/physiopathology , Neurons/pathology , Neurons/physiology , Exocytosis/physiology , Glycolysis/physiology , Humans , Induced Pluripotent Stem Cells , Synapses/pathology , Synapses/physiologyABSTRACT
Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant disease, characterized by the progressive ossification of skeletal muscles, fascia, tendons, and ligaments. In most cases, the great toes of patients show symmetrical congenital malformations. The causative gene for FOP has been identified as the activin A receptor, type 1 (ACVR1) gene (ACVR1). The ACVR1 R206H mutation is the most common mutation among FOP patients, and the ACVR1 G356D mutation has been identified as a rare mutation in a Japanese FOP patient with slow progression. In addition to musculoskeletal abnormalities, a series of autopsy studies described one FOP case, without genetic testing to identify ACVR1 mutation, showing nodular heterotopia at the edge of the fourth ventricle. Here, we report the general autopsy findings for a 75-year-old man with FOP, caused by the ACVR1 G356D mutation, including the precise examination of brainstem lesions. Postmortem examination revealed unique symmetrical glial hyperplasia of the pons and medulla oblongata. Microscopically, lesions of the pons involving residual neurons and lesions of the medulla oblongata consisted of subependymal cells. Immunohistochemical analysis of these lesions revealed developmental anomalies, with different cellular components. In this report, for the first time, we present the neuropathological description of a patient with genetically confirmed FOP and symmetrical glial hyperplasia of the pons and medulla oblongata. The presented pathological findings, in conjunction with previous reports implying that the glial hyperplasia of the brainstem is common in FOP, suggest that ACVR1 may play an unclarified developmental role in the human brainstem.
Subject(s)
Brain Stem/pathology , Hyperplasia/pathology , Myositis Ossificans/pathology , Neuroglia/pathology , Aged , Genetic Testing/methods , Humans , Hyperplasia/genetics , Male , Mutation/genetics , Myositis Ossificans/diagnosis , Myositis Ossificans/geneticsABSTRACT
OBJECTIVES: A pre-possible multiple system atrophy (MSA) phase, that is, the period between symptom onset and satisfying the second consensus diagnostic criteria for possible or probable MSA, may exist. The aim of the study was to identify the pre-possible MSA phase and to pursue the earlier diagnosis of MSA. MATERIALS & METHODS: We reviewed 52 patients with a clinical diagnosis of MSA and 430 patients showing any signs of parkinsonism, sporadic cerebellar ataxia, or autonomic failure with other clinical diagnoses. RESULTS: The pre-possible MSA phase was noted in 35 patients with a clinical diagnosis of MSA and 13 patients with other clinical diagnoses. During this phase, 16 patients presented with autonomic features first, while they presented later in 32 patients. Between these patients, there was no significant difference regarding parkinsonian, cerebellar features, levodopa response, or Babinski sign with hyperreflexia. Comparisons by autonomic features or autonomic function tests could not be performed due to the small number of patients. "Atrophy on magnetic resonance imaging of the putamen, middle cerebellar peduncle, pons, or cerebellum" and "new or increased snoring" showed high positive predictive values for MSA. CONCLUSION: A pre-possible MSA phase exists. Improved earlier diagnosis of MSA depends on the sensitivity and positive predictive value of autonomic features or autonomic function tests and on the sensitivity of "atrophy on magnetic resonance imaging of the putamen, middle cerebellar peduncle, pons, or cerebellum" and "new or increased snoring" during the pre-possible MSA phase.
Subject(s)
Early Diagnosis , Multiple System Atrophy/diagnosis , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Multiple System Atrophy/complications , Multiple System Atrophy/pathologyABSTRACT
INTRODUCTION: Patients with neurological and neuromuscular disorders (NNMD) frequently experience swallowing disorders that increase aspiration pneumonia risk and therefore require specialized diets or tube feeding. Diet type level usually is assessed by video fluoroscopic swallowing study (VFSS). To identify a simpler assessment method, we examined the association between diet type (based on the Functional Oral Intake Scale [FOIS]) diet type and maximum tongue pressure (MTP). METHODS: From 2011-2020, FOIS diet type level and MTP were assessed in a sample of 927 patients. Of these patients, 186 had Parkinson's disease (PD), 69 had Parkinson-related disease (PRD), 61 had multiple system atrophy (MSA), 42 had spinocerebellar degeneration (SCD), 147 had amyotrophic lateral sclerosis (ALS), 180 had myotonic dystrophy type 1 (DM1), and 242 had Duchenne muscular dystrophy (DMD). VFSS was conducted while patients swallowed water and foods containing barium. MTP measurements were collected the same day. Participants' diet type level was adjusted based on the VFSS, with some participants requiring multiple examinations. Relationships between diet type level and MTP were tested using univariate and Spearman rank correlation analyses. RESULTS: Mean MTP for the entire NNMD group (25.5 ± 13.1 kPa) was lower than that of healthy elderly individuals, as determined in previous reports. The highest MTP was found in the MSA group (32.2 ± 15.7 kPa) and the lowest in the DM1 group (19.1 ± 9.0 kPa). Diet type level was highest in the MSA group (5.8 ± 1.4) and lowest in the DMD group (5.2 ± 1.7). A significant correlation was observed between diet type level and MTP (R = 0.384, p < 0.001). The optimum MTP cutoff values-detected using ROC curves to predict a requirement to change to a dysphagia diet-was highest in the DMD group (29.0 kPa) and lowest in the ALS group (12.3 kPa). CONCLUSIONS: The decision to change NNMD patients to a dysphagia diet can be made based on MTP. Modifying a patient's oral diet (FOIS level ≤ 5) should be considered for those with a MTP of 10-25 kPa, with the cutoff value varying by disease.
Subject(s)
Deglutition Disorders/diagnostic imaging , Deglutition/physiology , Diet/methods , Nervous System Diseases/diagnostic imaging , Neuromuscular Diseases/diagnostic imaging , Tongue/physiology , Administration, Oral , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cohort Studies , Deglutition Disorders/epidemiology , Deglutition Disorders/physiopathology , Diet/trends , Eating/physiology , Female , Fluoroscopy/methods , Humans , Male , Middle Aged , Nervous System Diseases/epidemiology , Nervous System Diseases/physiopathology , Neuromuscular Diseases/epidemiology , Neuromuscular Diseases/physiopathology , Pressure , Video Recording/methods , Young AdultABSTRACT
Disaster countermeasures have been implemented by the Japanese Society of Neurology based on the experience of support to the areas affected by the Great East Japan Earthquake on March 11, 2011. The countermeasures activity began at the end of 2011. We, the Committee for Measures Against Disaster, officially started work in 2014. We developed a support network to urgently deal with patients with intractable neurological disease at the time of disaster and strengthen disaster measures, including effective disaster countermeasure training. During the 2016 Kumamoto earthquake, we realized the need to prepare for natural disasters, leading to a state of emergency, at normal times. A list of vulnerable people should be prepared and the individual support plan for disaster should be confirmed during normal times. Furthermore, during disaster, livelihood support is required for patients with intractable neurological disease living in evacuation centers in affected areas. Therefore, we compiled and published the book, titled "The manual of disaster countermeasures," in 2017. The Committee for Measures Against Disaster in the Japanese Society of Neurology has appointed a liaison officer for patients with intractable neurological disease in each prefecture. The liaison's role of is gathering and disseminating information on the disaster-hit areas, arranging medical support, and coordinating health activities, when natural disasters occur. It is hoped that the liaison officer will play an active role both at normal times and during disaster, even unforeseen ones. Although we hope for the best, we aim to be prepared for the worst.
Subject(s)
Community Health Services , Disaster Planning/methods , Earthquakes , Health Personnel , Manuals as Topic , Nervous System Diseases , Neurology/organization & administration , Professional Role , Societies, Medical/organization & administration , Humans , JapanABSTRACT
GM1 gangliosidosis is a lysosomal storage disease caused by loss of lysosomal ß-galactosidase activity and characterized by progressive neurodegeneration due to massive accumulation of GM1 ganglioside in the brain. Here, we generated induced pluripotent stem cells (iPSCs) derived from patients with GM1 gangliosidosis, and the resultant neurons showed impaired neurotransmitter release as a presynaptic function and accumulation of GM1 ganglioside. Treatment of normal neurons with GM1 ganglioside also disturbed presynaptic function. A high-content drug-screening system was then established and identified two compounds as drug candidates for GM1 gangliosidosis. Treatment of the patient-derived neurons with the candidate agents activated autophagy pathways, reducing GM1 ganglioside accumulation in vitro and in vivo, and restoring the presynaptic dysfunction. Our findings thus demonstrated the potential value of patient-derived iPSC lines as cellular models of GM1 gangliosidosis and revealed two potential therapeutic agents for future clinical application.
Subject(s)
Autophagy , G(M1) Ganglioside/metabolism , Gangliosidosis, GM1/metabolism , Neurons/metabolism , Neuroprotective Agents/pharmacology , Cells, Cultured , Drug Development/methods , Gangliosidosis, GM1/pathology , Humans , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Neurons/cytology , Neurons/drug effects , Synapses/drug effects , Synapses/metabolismABSTRACT
Various methods of rehabilitation for dysphagia have been suggested through the experience of treating stroke patients. Although most of these patients recover their swallowing function in a short period, dysphagia in Parkinson's disease (PD) and Parkinson-related disorder (PRD) degenerates with disease progression. Muscle rigidity and bradykinesia are recognized as causes of swallowing dysfunction, and it is difficult to easily apply the strategies for stroke to the rehabilitation of dysphagia in PD patients. Disease severity, weight loss, drooling, and dementia are important clinical predictors. Silent aspiration is a pathognomonic sign that may lead to aspiration pneumonia. Severe PD patients need routine video fluoroscopy or video endoscopy to adjust their food and liquid consistency. Patients with PRD experience rapid progression of swallowing dysfunction. Nutrition combined with nasogastric tube feeding or percutaneous endoscopic gastrostomy feeding should be considered owing to the increased risk of aspiration and difficulty administrating oral nutrition.
Subject(s)
Deglutition Disorders/rehabilitation , Parkinson Disease/rehabilitation , Respiratory Aspiration/prevention & control , Deglutition/physiology , Deglutition Disorders/diagnosis , Deglutition Disorders/etiology , Disease Progression , Enteral Nutrition/methods , Humans , Hypokinesia/physiopathology , Muscle Rigidity/physiopathology , Parkinson Disease/complications , Parkinson Disease/physiopathology , Pneumonia, Aspiration/prevention & control , Stroke RehabilitationABSTRACT
Objective Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease characterized by the progressive loss of the upper and lower motor neurons that progresses to paralysis of almost all skeletal muscles of the extremities, bulbar, and respiratory system. Although most ALS cases are sporadic, about 10% are dominantly inherited. We herein report an atypical phenotype of familial ALS (fALS). To elucidate the phenotype-genotype correlation of this atypical phenotype of fALS, clinical and genetic investigations were performed. Methods and Patients Five sibling patients (three men, two women) from a Japanese family and one healthy sibling (a woman) were clinically interviewed and examined. Genetic analyses, including genome-wide linkage analyses and whole-exome sequencing, were performed using genomic DNA extracted from the peripheral blood samples of these siblings. Results The clinical features of fALS are characterized by slow progression (mean duration of the disease±standard deviation [SD]: 19.6±3.9 years) and lower extremities-predominant late-onset muscular weakness (mean onset of muscular weakness±SD: 52.8±2.6 years). Genetic analyses revealed novel heterozygous missense mutations of c.2668C>T, p.R890C in the PLEC gene and c.421G>C, p.V141L in the ST3GAL6 gene in all affected siblings. Conclusion A new atypical fALS family with a benign clinical course is herein reported. We identified two candidate gene mutations of PLEC and ST3GAL6 linked to this phenotype.
Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/mortality , Genetic Predisposition to Disease , Motor Neurons/physiology , Muscle Weakness/physiopathology , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/physiopathology , Aged , Aged, 80 and over , Amyotrophic Lateral Sclerosis/physiopathology , Asian People , Fatal Outcome , Female , Genotype , Humans , Lower Extremity/physiopathology , Male , Middle Aged , Muscle, Skeletal/physiopathology , Mutation , Neurodegenerative Diseases/mortality , PhenotypeABSTRACT
Spinocerebellar ataxia type 8 (SCA8) is caused by a bidirectionally transcribed CTG·CAG expansion that results in the in vivo accumulation of CUG RNA foci, an ATG-initiated polyGln and a polyAla protein expressed by repeat-associated non-ATG (RAN) translation. Although RAN proteins have been reported in a growing number of diseases, the mechanisms and role of RAN translation in disease are poorly understood. We report a novel toxic SCA8 polySer protein which accumulates in white matter (WM) regions as aggregates that increase with age and disease severity. WM regions with polySer aggregates show demyelination and axonal degeneration in SCA8 human and mouse brains. Additionally, knockdown of the eukaryotic translation initiation factor eIF3F in cells reduces steady-state levels of SCA8 polySer and other RAN proteins. Taken together, these data show polySer and WM abnormalities contribute to SCA8 and identify eIF3F as a novel modulator of RAN protein accumulation.
Subject(s)
Aging/metabolism , Eukaryotic Initiation Factor-3/metabolism , Nerve Tissue Proteins/metabolism , Spinocerebellar Degenerations/metabolism , White Matter/metabolism , Aging/genetics , Aging/pathology , Animals , Eukaryotic Initiation Factor-3/genetics , HeLa Cells , Humans , Mice , Mice, Transgenic , Nerve Tissue Proteins/genetics , Spinocerebellar Degenerations/genetics , Spinocerebellar Degenerations/pathology , White Matter/pathologyABSTRACT
Essential hypersomnia (EHS) is a lifelong disorder characterized by excessive daytime sleepiness without cataplexy. EHS is associated with human leukocyte antigen (HLA)-DQB1*06:02, similar to narcolepsy with cataplexy (narcolepsy). Previous studies suggest that DQB1*06:02-positive and -negative EHS are different in terms of their clinical features and follow different pathological pathways. DQB1*06:02-positive EHS and narcolepsy share the same susceptibility genes. In the present study, we report a genome-wide association study with replication for DQB1*06:02-negative EHS (408 patients and 2247 healthy controls, all Japanese). One single-nucleotide polymorphism, rs10988217, which is located 15-kb upstream of carnitine O-acetyltransferase (CRAT), was significantly associated with DQB1*06:02-negative EHS (P = 7.5 × 10-9, odds ratio = 2.63). The risk allele of the disease-associated SNP was correlated with higher expression levels of CRAT in various tissues and cell types, including brain tissue. In addition, the risk allele was associated with levels of succinylcarnitine (P = 1.4 × 10-18) in human blood. The leading SNP in this region was the same in associations with both DQB1*06:02-negative EHS and succinylcarnitine levels. The results suggest that DQB1*06:02-negative EHS may be associated with an underlying dysfunction in energy metabolic pathways.
Subject(s)
Carnitine O-Acetyltransferase/genetics , Chromosomes, Human, Pair 9/genetics , Disorders of Excessive Somnolence/genetics , HLA-DQ beta-Chains/genetics , Polymorphism, Single Nucleotide , Disorders of Excessive Somnolence/enzymology , Female , Genome-Wide Association Study , Humans , MaleABSTRACT
Huntington's disease (HD) is an intractable neurodegenerative disorder caused by mutant Huntingtin (HTT) proteins that adversely affect various biomolecules and genes. MicroRNAs (miRNAs), which are functional small non-coding RNAs, are also affected by mutant HTT proteins. Here, we show amelioration in motor function and lifespan of HD-model mice, R6/2 mice, by supplying miR-132 to HD brains using a recombinant adeno-associated virus (rAAV) miRNA expression system. miR-132 is an miRNA related to neuronal maturation and function, but the level of miR-132 in the brain of R6/2 mice was significantly lower than that of wild-type mice. Our miR-132 supplemental treatment, i.e., supplying miR-132 to the brain, produced symptomatic improvement or retarded disease progression in R6/2 mice; interestingly, it had little effect on disease-causing mutant HTT mRNA expression and its products. Therefore, the findings suggest that there may be a therapeutic way to treat HD without inhibiting and/or repairing disease-causing HTT genes and gene products. Although miR-132 supplement may not be a definitive treatment for HD, it may become a therapeutic method for relieving HD symptoms and delaying HD progression.
ABSTRACT
The aim of the present study was to compare the efficacy of magnetic resonance imaging (MRI) and 123I-labeled 2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)nortropane single photon emission computed tomography (123I-FP-CIT SPECT) for determining the clinical severity of patients with multiple system atrophy with Parkinsonism (MSA-P). MRI and 123I-FP-CIT SPECT images from 17 patients with MSA-P as diagnosed using the Unified MSA Rating Scale part IV (UMSARS IV) score were compared. Brain MRI scans were available for all 17 patients and 123I-FP-CIT SPECT images were available for 12 patients. Putaminal atrophy (PA), hyperintense putaminal rim (HPR), hyperintense pons (hot cross bun sign, HCB), atrophy of the cerebellar vermis and hemisphere (cerebellar atrophy, CA) and other abnormalities were evaluated in the MRI scans. Distribution of striatal uptake (SU) and the specific binding ratio (SBR) on each side of the bilateral striatum were evaluated using 123I-FP-CIT SPECT images. No significant associations were observed between HPR, HCB, CA and UMSARS IV score. However, the frequency of PA increased significantly with higher UMSARS IV score (P<0.05). No significant association was observed between UMSARS IV score and SBR. The results of the present study suggest that PA, which is known to be a diagnostic indicator for MSA-P, may be used to determine the clinical severity of MSA-P with greater efficacy than other MRI findings, including HPR, HCB and CA and 123I-FP-CIT SPECT results.
ABSTRACT
BACKGROUND AND AIM: Early clinical diagnosis of progressive supranuclear palsy (PSP) remains challenging. AIM: We attempted to identify any sign or symptom to diagnose PSP earlier. METHODS: A total of 401 patients, 40 with PSP and 361 with other neurodegenerative disorders, were included. We followed these patients for at least 1 year since 2009. We reviewed the signs and symptoms of patients with PSP in a standardized manner, and observed four manifestations: "vertical supranuclear gaze abnormality," "movement disorders," "pseudobulbar palsy" and "dementia of frontal type." Features, such as symmetric parkinsonism, freezing of gait, postural instability, dysarthria and/or dysphagia, or dementia of frontal type, were considered core clinical features. RESULTS: In patients with PSP, "movement disorders" was the most common manifestation, whereas "vertical supranuclear gaze abnormality" was uncommon during the early disease course. A total of 16 patients fulfilled the National Institute for Neurological Disorders and Stroke and Society for PSP criteria for possible PSP at their first clinic visit. Of the remaining 24 patients, 15 presented with one or more core clinical features before fulfilling the criteria for possible PSP; nine patients had a clinical diagnosis of PSP but never fulfilled the criteria. A total of 49 of the 361 patients with other neurodegenerative disorders had core clinical features. A comparison showed that freezing of gait differentiated the groups the best over the disease course. CONCLUSION: Freezing of gait is an early feature that might improve the clinical diagnosis of PSP, whereas vertical supranuclear gaze abnormality is not.