Satoshi Yokoi

FUS regulates AMPA receptor function and FTLD/ALS-associated behaviour via GluA1 mRNA stabilization

FUS is an RNA/DNA-binding protein involved in multiple steps of gene expression and is associated with amyotrophic lateral sclerosis (ALS) and fronto-temporal lobar degeneration (FTLD). However, the specific disease-causing and/or modifying mechanism mediated by FUS is largely unknown. Here we evaluate intrinsic roles of FUS on synaptic functions and animal behaviours. We find that FUS depletion downregulates GluA1, a subunit of AMPA receptor. FUS binds GluA1 mRNA in the vicinity of the 3′ terminus and controls poly (A) tail maintenance, thus regulating stability. GluA1 reduction upon FUS knockdown reduces miniature EPSC amplitude both in cultured neurons and in vivo. FUS knockdown in hippocampus attenuates dendritic spine maturation and causes behavioural aberrations including hyperactivity, disinhibition and social interaction defects, which are partly ameliorated by GluA1 reintroduction. These results highlight the pivotal role of FUS in regulating GluA1 mRNA stability, post-synaptic function and FTLD-like animal behaviours.

FUS immunoreactivity of neuronal and glial intranuclear inclusions in intranuclear inclusion body disease

F. Mori, K. Tanji, T. Kon, S. Odagiri, M. Hattori, Y. Hoshikawa, C. Kono, K. Yasui, S. Yokoi, Y. Hasegawa, M. Yoshida and K. Wakabayashi (2012) Neuropathology and Applied Neurobiology38, 322–328

Altered Tau Isoform Ratio Caused by Loss of FUS and SFPQ Function Leads to FTLD-like Phenotypes

Fused in sarcoma (FUS) and splicing factor, proline- and glutamine-rich (SFPQ) are RNA binding proteins that regulate RNA metabolism. We found that alternative splicing of the Mapt gene at exon 10, which generates 4-repeat tau (4R-T) and 3-repeat tau (3R-T), is regulated by interactions between FUS and SFPQ in the nuclei of neurons. Hippocampus-specific FUS- or SFPQ-knockdown mice exhibit frontotemporal lobar degeneration (FTLD)-like behaviors, reduced adult neurogenesis, accumulation of phosphorylated tau, and hippocampal atrophy with neuronal loss through an increased 4R-T/3R-T ratio. Normalization of this increased ratio by 4R-T-specific silencing results in recovery of the normal phenotype. These findings suggest a biological link among FUS/SFPQ, tau isoform alteration, and phenotypic expression, which may function in the early pathomechanism of FTLD.

Clinicopathological features of adult-onset neuronal intranuclear inclusion disease

Neuronal intranuclear inclusion disease (NIID) has highly variable clinical manifestations. Sone et al. describe the clinical and pathological features of 57 adult-onset cases diagnosed by postmortem dissection/antemortem skin biopsy. They report ‘dementia dominant’ and ‘limb weakness’ subtypes, and recommend consideration of NIID in the differential diagnosis of leukoencephalopathy and neuropathy.

Chronological changes of 123I-MIBG myocardial scintigraphy and clinical features of Parkinson's disease

Objectives The aim of this study was to investigate chronological changes of 123I-meta-iodobenzylguanidine (MIBG) myocardial scintigraphy and its relation to clinical features in patients with Parkinsons disease (PD), and to characterise patients with PD with normal or mildly low MIBG uptakes at their early stages. Methods The participants were 70 patients with PD who underwent 123I-MIBG myocardial scintigraphy twice or more. A cluster analysis was performed using parameters calculated from heart to mediastinum (H/M) ratio and washout ratio (WR). Results At baseline, the mean early H/M ratio (H/M(E)), delayed H/M ratio (H/M(D)) and WR were 1.83, 1.69 and 41.7%, respectively. After a mean interval of 3.0 years, follow-up studies showed significantly declined H/M(E) (1.69, p<0.001), declined H/M(D) (1.47, p<0.001) and enhanced WR (43.8%, p=0.007). Our longitudinal observations revealed that there existed heterogeneous changes in MIBG uptakes among patients. The cluster analysis classified the patients into two subgroups: 42 patients with markedly low MIBG uptakes at baseline (group A) and 28 patients with normal or mildly low MIBG uptakes at baseline (group B). Group B showed a significantly higher ratio of females, younger age at onset, lower Hoehn and Yahr stage and less demented, compared with group A. Conclusions Follow-up studies of MIBG divided the patients with PD into two major subgroups. A subgroup of patients with PD with normal or mildly low MIBG uptakes at the early stages of illness was characterised by female-dominant, young onset, slow progression in motor dysfunctions and preserved cognitive function. Trial registration number 1033.

Ubiquitin-related proteins in neuronal and glial intranuclear inclusions in intranuclear inclusion body disease

Recent studies have shown that eosinophilic intranuclear inclusions (INI) in the brain of patients with intranuclear inclusion body disease (INIBD) are immunopositive for ubiquitin and ubiquitin‐related proteins (URP). However, the extent and frequency of URP‐immunoreactive inclusions in INIBD are uncertain. We immunohistochemically examined the brain, spinal cord and dorsal root ganglia from five patients with INIBD, using a virtual slide system with sequential staining of the same sections with hematoxylin and eosin and by immunolabeling with antibodies against ubiquitin and URP (NEDD8, NUB1, SUMO‐1 and SUMO‐2). Intranuclear inclusions were widely distributed in neurons and glial cells in all the cases. Sequential staining revealed that 100% of INI in neurons and glial cells were positive for ubiquitin. Moreover, the majority or a significant proportion of INI were positive for NEDD8, NUB1, SUMO‐1 and SUMO‐2. However, the proportions of NEDD8‐, NUB1‐ and SUMO‐1‐positive inclusions were significantly higher in neurons than in glial cells (P < 0.05). These findings suggest that proteins related to ubiquitination and proteasomal degradation are involved in the formation of INI in INIBD.

Necklace cytoplasmic bodies in hereditary myopathy with early respiratory failure

Background In hereditary myopathy with early respiratory failure (HMERF), cytoplasmic bodies (CBs) are often localised in subsarcolemmal regions, with necklace-like alignment (necklace CBs), in muscle fibres although their sensitivity and specificity are unknown. Objective To elucidate the diagnostic value of the necklace CBs in the pathological diagnosis of HMERF among myofibrillar myopathies (MFMs). Methods We sequenced the exon 343 of TTN gene (based on ENST00000589042), which encodes the fibronectin-3 (FN3) 119 domain of the A-band and is a mutational hot spot for HMERF, in genomic DNA from 187 patients from 175 unrelated families who were pathologically diagnosed as MFM. We assessed the sensitivity and specificity of the necklace CBs for HMERF by re-evaluating the muscle pathology of our patients with MFM. Results TTN mutations were identified in 17 patients from 14 families, whose phenotypes were consistent with HMERF. Among them, 14 patients had necklace CBs. In contrast, none of other patients with MFM had necklace CBs except for one patient with reducing body myopathy. The sensitivity and specificity were 82% and 99%, respectively. Positive predictive value was 93% in the MFM cohort. Conclusions The necklace CB is a useful diagnostic marker for HMERF. When muscle pathology shows necklace CBs, sequencing the FN3 119 domain of A-band in TTN should be considered.

Mononeuritis multiplex with tumefactive cellular infiltration in a patient with reactive lymphoid hyperplasia with increased immunoglobulin G4–positive cells

We describe a 54-year-old man with mononeuritis multiplex and reactive lymphoid hyperplasia with increased immunoglobulin G4 (IgG4)-positive cells. Asymmetrical numbness and weakness had advanced stepwise for 6 years. Serum immunoglobulin G, IgG4, and immunoglobulin E levels were elevated, whereas M protein was not detected. Chest and abdominal computed tomography showed generalized lymphadenopathy. Inguinal lymph node biopsy revealed expansion of the interfollicular area with infiltration of IgG4-positive cells, of which the absolute number was greater than 100 per high-power field, and the percentage of IgG4+/immunoglobulin G+ plasma cells was 33%. Sural nerve biopsy disclosed axonal neuropathy with tumefactive lymphoid infiltrate in epineurium, but IgG4-positve plasma cells and fibrosis were not detected. Symptoms and laboratory data were improved with oral glucocorticoid therapy at a dose of 0.6 mg/kg per day. Although the causal mechanisms of neuropathy should be determined in future studies, peripheral nerve involvement may occur in patients with reactive lymphoid hyperplasia with increased IgG4-positive cells.

Typicality analysis of the combination of ingredients in a cooking recipe for assisting the arrangement of ingredients

As the number of cooking recipes posted on the Web increases, it becomes difficult to find a cooking recipe that a user needs. Moreover, even if it can be done, it is still difficult for users to arrange the cooking recipe, for example, by replacing ingredients with different ones. To deal with such problems, we propose a framework for typicality analysis of the combination of ingredients. The framework calculates a typicality value for each combination of ingredients. The list of ingredients can be arranged by adjusting the typicality value by adding or removing ingredients iteratively. The effectiveness of the proposed framework was confirmed through subjective experiments.

Pathological background of subcortical hyperintensities on diffusion-weighted images in a case of neuronal intranuclear inclusion disease.

AIMS Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disorder with eosinophilic intranuclear inclusion bodies. The variable symptoms of NIID increase the difficulty in an antemortem diagnosis. NIID shows leukoencephalopathy on brain magnetic resonance imaging MRI, but the significance of the radiological findings have not been clarified. METHODS We examined an autopsied case of NIID with subcortical linear hyperintensities on diffusion weighted imaging (DWI) and leukoencephalopathy on fluid attenuation inversion recovery (FLAIR) imaging. Semiquantitative analysis was performed by merging coronal sections of DWI and identical hematoxylin-eosin (H & E) stained brain specimens. The severity of spongiotic changes, the common pathological findings of NIID, were quantified and compared with MRI lesions classified by DWI signals. RESULTS The white matter showed diffuse myelin pallor, and multiple focal spongiotic changes were present in the subcortical white matter proximal to the U-fibers. Spongiotic changes were restricted in the lesions with subcortical linear DWI high signals. CONCLUSION Subcortical DWI high signals in NIID strongly correlate with pathological spongiotic changes of NIID. Subcortical spongiotic changes may be a characteristic finding of NIID.
.