A case report of an individual with Creutzfeldt-Jakob disease characterized by prolonged isolated thalamic lesions and rare MM2-cortical-type pathology.

Background: Diffusion-weighted magnetic resonance imaging (DWI) is essential for diagnosing Creutzfeldt-Jakob disease (CJD). Thalamic lesions are rarely detected by DWI in sporadic CJD (sCJD) cases with methionine homozygosity at polymorphic codon 129 (129MM) of the prion protein (PrP) gene. Here, we describe an unusual sCJD case, characterized by prolonged isolated thalamic diffusion hyperintensities and atypical brain pathology, in combination with the 129MM genotype.

Hereditary spastic paraplegia and extensive leukoencephalopathy: a case report of a unique phenotype associated with a GJB1/Cx32 p.Pro174Ser variant.

Background: Pathogenic variants in Gap junction protein beta 1 (GJB1), which encodes Connexin 32, are known to cause X-linked Charcot-Marie-Tooth disease (CMTX), the second most common form of CMT. CMTX presents with the following five central nervous systems (CNS) phenotypes: subclinical electrophysiological abnormalities, mild fixed abnormalities on neurological examination and/or imaging, transient CNS dysfunction, cognitive impairment, and persistent CNS manifestations.

Case Presentation: A 40-year-old Japanese male showed CNS symptoms, including nystagmus, prominent spastic paraplegia, and mild cerebellar ataxia, accompanied by subclinical peripheral neuropathy.

Identification of small molecule inhibitors of G3BP-driven stress granule formation.

Stress granule formation is triggered by the release of mRNAs from polysomes and is promoted by the action of the RNA-binding proteins G3BP1/2. Stress granules have been implicated in several disease states, including cancer and neurodegeneration. Consequently, compounds that limit stress granule formation or promote their dissolution have potential as both experimental tools and novel therapeutics.

RNA Foci in Two bi-Allelic RFC1 Expansion Carriers.

Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) is a late-onset, autosomal recessive neurodegenerative disorder caused by biallelic AAGGG/ACAGG repeat expansion (AAGGG-exp/ACAGG-exp) in RFC1. The recent identification of patients with CANVAS exhibiting compound heterozygosity for AAGGG-exp and truncating variants supports the loss-of-function of RFC1 in CANVAS patients. We investigated the pathological changes in 2 autopsied patients with CANVAS harboring biallelic ACAGG-exp and AAGGG-exp.

A murine model of hnRNPH2-related neurodevelopmental disorder reveals a mechanism for genetic compensation by Hnrnph1.

Mutations in HNRNPH2 cause an X-linked neurodevelopmental disorder with features that include developmental delay, motor function deficits, and seizures. More than 90% of patients with hnRNPH2 have a missense mutation within or adjacent to the nuclear localization signal (NLS) of hnRNPH2. Here, we report that hnRNPH2 NLS mutations caused reduced interaction with the nuclear transport receptor Kapβ2 and resulted in modest cytoplasmic accumulation of hnRNPH2.

Identification of small molecule inhibitors of G3BP-driven stress granule formation.

Stress granule formation is triggered by the release of mRNAs from polysomes and is promoted by the action of the paralogs G3BP1 and G3BP2. G3BP1/2 proteins bind mRNAs and thereby promote the condensation of mRNPs into stress granules. Stress granules have been implicated in several disease states, including cancer and neurodegeneration.

Phosphorylated CRMP1, axon guidance protein, is a component of spheroids and is involved in axonal pathology in amyotrophic lateral sclerosis.

In amyotrophic lateral sclerosis (ALS), neurodegeneration is characterized by distal axonopathy that begins at the distal axons, including the neuromuscular junctions, and progresses proximally in a "dying back" manner prior to the degeneration of cell bodies. However, the molecular mechanism for distal axonopathy in ALS has not been fully addressed. Semaphorin 3A (Sema3A), a repulsive axon guidance molecule that phosphorylates collapsin response mediator proteins (CRMPs), is known to be highly expressed in Schwann cells near distal axons in a mouse model of ALS.

Inhibition of Crmp1 Phosphorylation at Ser522 Ameliorates Motor Function and Neuronal Pathology in Amyotrophic Lateral Sclerosis Model Mice.

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disorder that affects upper and lower motor neurons; however, its pathomechanism has not been fully elucidated. Using a comprehensive phosphoproteomic approach, we have identified elevated phosphorylation of Collapsin response mediator protein 1 (Crmp1) at serine 522 in the lumbar spinal cord of ALS model mice overexpressing a human superoxide dismutase mutant (SOD1). We investigated the effects of Crmp1 phosphorylation and depletion in mice using Crmp1 (Ser522→Ala) knock-in ( ) mice in which the S522 phosphorylation site was abolished and knock-out () mice, respectively.

Ubiquitination is essential for recovery of cellular activities after heat shock.

Eukaryotic cells respond to stress through adaptive programs that include reversible shutdown of key cellular processes, the formation of stress granules, and a global increase in ubiquitination. The primary function of this ubiquitination is thought to be for tagging damaged or misfolded proteins for degradation. Here, working in mammalian cultured cells, we found that different stresses elicited distinct ubiquitination patterns.

Clinical evidence that a dysregulated master neural network modulator may aid in diagnosing schizophrenia.

There are no validated biomarkers for schizophrenia (SCZ), a disorder linked to neural network dysfunction. We demonstrate that collapsin response mediator protein-2 (CRMP2), a master regulator of cytoskeleton and, hence, neural circuitry, may form the basis for a biomarker because its activity is uniquely imbalanced in SCZ patients. CRMP2's activity depends upon its phosphorylation state.

SGTA associates with intracellular aggregates in neurodegenerative diseases.

Intracellular aggregates are a common pathological hallmark of neurodegenerative diseases such as polyglutamine (polyQ) diseases, amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), and multiple system atrophy (MSA). Aggregates are mainly formed by aberrant disease-specific proteins and are accompanied by accumulation of other aggregate-interacting proteins. Although aggregate-interacting proteins have been considered to modulate the formation of aggregates and to be involved in molecular mechanisms of disease progression, the components of aggregate-interacting proteins remain unknown.

Case Report: Anti-MOG Antibody Seroconversion Accompanied by Dimethyl Fumarate Treatment.

Here we report three cases of anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) mimicking multiple sclerosis in which seropositivity for anti-MOG antibodies occurred during disease-modifying drug dimethyl fumarate (DMF) treatment. These patients developed relapses with anti-MOG antibody seroconversion after switching from fingolimod or steroid pulse therapy to DMF, which was associated with peripheral lymphocyte recovery. MOGAD is considered a humoral immune disease, and DMF reportedly enhances Th2-skewed humoral immune activity.

Tonsillectomy Improved Therapeutic Response in Anti-SRP Myopathy With Chronic Tonsillitis.

Chronic tonsillitis has been attracted attention as a source of abnormal immune responses and a possible trigger of autoimmune diseases such as IgA nephritis, IgA vasculitis, palmoplantar pustulosis, psoriasis, rheumatoid arthritis, Behçet's disease, and myositis. Here we present the first report of anti-signal recognition particle antibody-associated necrotizing myopathy (anti-SRP myopathy) with IgA nephropathy and chronic tonsillitis in which the therapeutic response to intravenous immunoglobulin (IVIG) treatment was dramatically improved after tonsillectomy and accompanied by a rapid increase in ΔIgG, defined as the change in serum IgG levels 2 weeks after the start of IVIG treatment relative to pre-treatment levels. Moreover, serum anti-SRP antibody titers became undetectable after tonsillectomy even though the resected tonsils did not produce anti-SRP antibodies.

De novo CACNA1G variants in developmental delay and early-onset epileptic encephalopathies.

Introduction: Variants of CACNA1G, which encodes Ca3.1, have been reported to be associated with various neurological disorders.

Methods: Whole-exome sequencing of genomic DNA from 348 Japanese patients with neurodevelopmental disorders and their parents was conducted, and de novo variants of CACNA1G were extracted.

[A case of subacute hypertrophic pachymeningitis caused by Pseudomonas aeruginosa infection presenting with subdural hygroma].

A 78-year-old woman with bilateral fungal sinusitis, which resulted in right orbital apex syndrome, underwent endoscopic sinus surgery and optic nerve decompression. Two months after the operation, she complained of anxiety and insomnia. Head CT showed subdural hematoma-like effusion and burr hole drainage was conducted.

CCR2 is localized in microglia and neurons, as well as infiltrating monocytes, in the lumbar spinal cord of ALS mice.

It remains controversial whether circulating monocytes expressing CCR2 infiltrate the central nervous system (CNS) and contribute to pathogenicity of amyotrophic lateral sclerosis (ALS). A previous report used conventional immunohistochemistry to show that CCR2 is exclusively expressed by astrocytes, but not infiltrating monocytes/microglia or neurons, in the spinal cords of ALS model mice. In this study, we assessed the cellular distribution of CCR2 in the CNS of ALS mice using CCR2-reporter mice (Ccr2-Cx3cr1-SOD1 Tg mice), a more sophisticated method for directly detecting the distribution of CCR2 protein.

Long-read sequencing identifies the pathogenic nucleotide repeat expansion in RFC1 in a Japanese case of CANVAS.

Recently, a recessively inherited intronic repeat expansion in replication factor C1 (RFC1) was identified in cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS). Here, we describe a Japanese case of genetically confirmed CANVAS with autonomic failure and auditory hallucination. The case showed impaired uptake of iodine-123-metaiodobenzylguanidine and I-ioflupane in the cardiac sympathetic nerve and dopaminergic neurons, respectively, by single-photon emission computed tomography.

Network-guided analysis of hippocampal proteome identifies novel proteins that colocalize with Aβ in a mice model of early-stage Alzheimer's disease.

Alzheimer's disease (AD) is an incurable neurodegenerative disease characterized by memory loss and neurotoxic amyloid beta (Aβ) plaques accumulation. Numerous pharmacological interventions targeting Aβ plaques accumulation have failed to alleviate AD. Also, the pathological alterations in AD start years before the onset of clinical symptoms.

GGC Repeat Expansion of NOTCH2NLC in Adult Patients with Leukoencephalopathy.

Leukoencephalopathies comprise a broad spectrum of disorders, but the genetic background of adult leukoencephalopathies has rarely been assessed. In this study, we analyzed 101 Japanese patients with genetically unresolved adult leukoencephalopathy using whole-exome sequencing and repeat-primed polymerase chain reaction for detecting GGC expansion in NOTCH2NLC. NOTCH2NLC was recently identified as the cause of neuronal intranuclear inclusion disease.

Ataxic phenotype with altered Ca3.1 channel property in a mouse model for spinocerebellar ataxia 42.

Spinocerebellar ataxia 42 (SCA42) is a neurodegenerative disorder recently shown to be caused by c.5144G > A (p.Arg1715His) mutation in CACNA1G, which encodes the T-type voltage-gated calcium channel Ca3.