Ichiro Yabe

Dr. Ichiro Yabe

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2006 in Journal of the Neurological Sciences
Verified
Journal Article
Closed access
IYIchiro Yabe
Ichiro Yabe
HSHiroyuki Soma
Hiroyuki Soma
ATAsako Takei
Asako Takei
NFNaoto Fujiki
Naoto Fujiki
TYTetsuro Yanagihara
Tetsuro Yanagihara
HSHidenao Sasaki
Hidenao Sasaki

24 October 2015 in Molecular Brain
Verified
Journal Article
Open access
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ITIkuko Takahashi-Iwata
Ikuko Takahashi-Iwata
YHYuka Hama
Yuka Hama
MMMasaaki Matsushima
Masaaki Matsushima
MHMakoto Hirotani
Makoto Hirotani
TKTakahiro Kano
Takahiro Kano
HSHidenao Sasaki
Hidenao Sasaki
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease, which leads to the loss of upper and lower motor neurons, with a currently unknown etiology. Specific biomarkers could help in early detection and diagnosis, and could also act as indicators of disease progression and therapy effectiveness. MicroRNAs (miRNAs) are small (18–25 nucleotides), single-stranded non-coding RNA molecules that play important regulatory roles in animals and plants by targeting mRNAs for cleavage or translational repression, and are essential for nervous system development. Many of the genes associated with genetic ALS have pathological biological pathways related to RNA metabolism, and their pathogenesis may be affecting the maturing processes of miRNA. We compared miRNA from the plasma of sALS patients and healthy controls using two cohorts; a discovery cohort analyzed with microarray (16 sALS patients and ten healthy controls) and a validation cohort confirmed with qPCR (48 sALS patients, 47 healthy controls and 30 disease controls). We measured the total amount of extracted RNA along with a spike-in control that ensured the quality of our quantification. A percentage of the 10–40 nt RNAs extracted from the total RNA showed a significant increase in ALS patients. There was a negative correlation between total RNA concentration and disease duration from onset to end point. Three of the miRNAs were up-regulated and six were down-regulated significantly in the discovery cohort. Since an internal control is required as a sample stability indicator of both the patients and controls in microarray analysis, we selected the miRNA showing the smallest dispersion and equivalency between the two groups’ mean value, and decided to use hsa-miR-4516. We found hsa-miR-4649-5p to be up-regulated, and hsa-miR-4299 to be down-regulated, where each was not influenced by clinical characteristics. EPHA4, a target gene linked to the nervous system which has also been reported to be a disease modifier of ALS, is the common and most notable target gene of hsa-miR-4649-5p and hsa-miR-4299. We have shown the relationship circulating plasma miRNA has with both healthy controls and diseased patients. Hsa-miR-4649-5p and hsa-miR-4299 have the potential to be ALS diagnosis biomarkers.

14 May 2019 in Molecular Brain
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Journal Article
Open access
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HUHisashi Uwatoko
Hisashi Uwatoko
YHYuka Hama
Yuka Hama
ITIkuko Takahashi-Iwata
Ikuko Takahashi-Iwata
SSShinichi Shirai
Shinichi Shirai
MMMasaaki Matsushima
Masaaki Matsushima
HSHidenao Sasaki
Hidenao Sasaki
MicroRNAs (miRNAs) are endogenous small (18–25 nt), single-stranded, non-coding RNAs that play key roles in post-transcriptional gene expression regulation. The expression profiles of miRNAs in biofluids and tissues change in various diseases. Multiple system atrophy (MSA) and Parkinson’s disease (PD) are both categorized as α-synucleinopathies and often present with similar clinical manifestations. This study aimed to identify miRNAs that are differently expressed in plasma samples of PD patients, MSA patients, and healthy controls. We used microarray analysis to screen for miRNAs that are up- and down-regulated in these patients and analyzed the relative-quantitative expression levels of the identified miRNAs by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Hsa-miR-671-5p, hsa-miR-19b-3p, and hsa-miR-24-3p showed significantly different expression levels among patients with MSA-C, MSA-P, or PD, and healthy controls. Hsa-miR-671-5p levels were lower in the MSA-P and PD than the MSA-C and control groups, hsa-miR-19b-3p levels were higher in the PD than the other groups, and hsa-miR-24-3p levels were higher in the PD than the MSA-C group. Hsa-miR-671-5p was the first miRNA shown to be expressed differently between MSA-C and MSA-P in plasma. Interestingly, the expression levels of hsa-miR-19b-3p and hsa-miR-24-3p were positively correlated, indicating that these miRNAs may be involved in the same processes in PD pathogenesis. Our findings suggest that hsa-miR-671-5p, hsa-miR-19b-3p, and hsa-miR-24-3p may reflect the pathophysiology or symptoms of PD and MSA.

1 May 2010 in Radiology
Verified
Journal Article
Closed access
KTKhin Khin Tha
Khin Khin Tha
STSatoshi Terae
Satoshi Terae
IYIchiro Yabe
Ichiro Yabe
TMTamaki Miyamoto
Tamaki Miyamoto
HSHiroyuki Soma
Hiroyuki Soma
HSHiroki Shirato
Hiroki Shirato
Purpose To determine whether diffusion-tensor (DT) imaging can demonstrate microstructural white matter abnormalities of multiple system atrophy (MSA) and to correlate these imaging findings with clinical signs and symptoms. Materials and Methods Institutional review board approval and written informed consent were obtained. DT imaging was performed in 16 patients with MSA with predominant cerebellar symptoms (MSA-C) (mean age, 60.0 years ± 5.1 [standard deviation]; range, 51–69 years) and 16 age-matched healthy subjects. Fractional anisotropy (FA) and mean diffusivity (MD) were compared voxel-by-voxel between the two groups by using a two-sample t test. Overlap maps were created to illustrate areas with FA and MD alterations. Correlation between DT imaging indexes and Barthel index score, scale for assessment and rating of ataxia (SARA) score, severity of orthostatic hypotension, age of disease onset, and disease duration was tested by using Spearman rank or Pearson product-moment correlation analysis. T2-weighted and proton density–weighted images of the patients were visually assessed. Results Widespread areas of FA reduction and MD elevation were observed in supra- and infratentorial white matter structures in patients with MSA (P < .05, false discovery rate corrected). Significant correlation (P < .01) between DT imaging indexes and Barthel index score, SARA score, severity of orthostatic hypotension, and disease duration was observed for multiple areas with FA and/or MD alterations. T2-weighted and proton density–weighted images showed no significant abnormality in supratentorial white matter. Conclusion DT imaging may help identify the microstructural white matter abnormalities of MSA-C. DT imaging may be useful for severity assessment of MSA-C. © RSNA, 2010 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10090988/-/DC1

5 September 2007 in Journal of Human Genetics
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Journal Article
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RBRehana Basri
Rehana Basri
IYIchiro Yabe
Ichiro Yabe
HSHiroyuki Soma
Hiroyuki Soma
HSHidenao Sasaki
Hidenao Sasaki
Autosomal dominant cerebellar ataxia (ADCA) is a genetically heterogeneous group of neurodegenerative disorders. To shed further light on the clinical and genetic spectrum of ADCA in Japan, we conducted a study to determine the frequency of a new variety of different subtypes of SCAs among ADCA patients. This current study was carried out from April 1999 to December 2006 on the basis of patients with symptoms and signs of ADCA disorders. PCR and/or direct sequencing were evaluated in a total of 113 families. Among them, 35 families were found to have the mutation associated with SCA6, 30 with SCA3, 11 with SCA1, five with SCA2, five with DRPLA, and one with SCA14. We also detected the heterozygous −16C → T single nucleotide substitution within the puratrophin-1 gene responsible for 16q22.1-linked ADCA in ten families. In this study, unusual varieties of SCA, including 27, 13, 5, 7, 8, 12, 17, and 16 were not found. Of the 113 patients, 14% had as yet unidentified ADCA mutations. The present study validates the prevalence of genetically distinct ADCA subtypes based on ethnic origin and geographical variation, and shows that 16q-linked ADCA has strong hereditary effects in patients with ADCAs in Japan.

16 January 2018 in Scientific Reports
Verified
Journal Article
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IYIchiro Yabe
Ichiro Yabe
HYHiroaki Yaguchi
Hiroaki Yaguchi
YKYasutaka Kato
Yasutaka Kato
YMYasuo Miki
Yasuo Miki
HTHidehisa Takahashi
Hidehisa Takahashi
HSHidenao Sasaki
Hidenao Sasaki
Clinical diagnosis of progressive supranuclear palsy (PSP) is sometimes difficult because various phenotypes have been identified. Here, we report a mutation in the bassoon (BSN) gene in a family with PSP-like syndrome. Their clinical features resembled not only those of PSP patients but also those of individuals with multiple system atrophy and Alzheimer’s disease. The neuropathological findings showed a novel three + four repeat tauopathy with pallido-luysio-nigral degeneration and hippocampal sclerosis. Whole-exome analysis of this family identified a novel missense mutation in BSN. Within the pedigree, the detected BSN mutation was found only in affected individuals. Further genetic analyses were conducted in probands from four other pedigrees with PSP-like syndrome and in 41 sporadic cases. Three missense mutations in BSN that are very rarely listed in databases of healthy subjects were found in four sporadic cases. Western blot analysis of tau following the overexpression of wild-type or mutated BSN revealed the possibility that wild-type BSN reduced tau accumulation, while mutated BSN lost this function. An association between BSN and neurological diseases has not been previously reported. Our results revealed that the neurodegenerative disorder associated with the original proband’s pedigree is a novel tauopathy, differing from known dementia and parkinsonism syndromes, including PSP.