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Featured researches published by Eisaku Ohama.


Amyotrophic Lateral Sclerosis | 2000

New consensus research on neuropathological aspects of familial amyotrophic lateral sclerosis with superoxide dismutase 1 (SOD1) gene mutations: Inclusions containing SOD1 in neurons and astrocytes

Shinsuke Kato; Miki Takikawa; Kenji Nakashima; Asao Hirano; Don W. Cleveland; Hirofumi Kusaka; Noriyuki Shibata; Masako Kato; Imaharu Nakano; Eisaku Ohama

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that primarily involves the motor neuron system. Approximately 5-10% of ALS is familial. Superoxide dismutase 1 (SOD1) gene mutations are shown to be associated with about 20% of familial ALS (FALS) patients. The neuronal Lewy-body-like hyaline inclusion (LBHI) and astrocytic hyaline inclusion (Ast-HI) are morphological hallmarks of certain SOD1-linked FALS patients with SOD1 gene mutant and transgenic mice expressing human SOD1 with G85R mutation. From the detailed immunohistochemic analyses, the essential common protein of both inclusions is SOD1. Ultrastructurally, both inclusions consist of granule-coated fibrils 15-25 nm in diameter. Based on the immuno-electron microscopical finding that these abnormal granulecoated fibrils are positive for SOD1, the formation (or aggregation) of the abnormal fibrils containing SOD1 would be essential evidence in diseases caused by various SOD1 mutations. The granule-coated fibrils are also modified by advanced glycation end products (AGEs). The AGEs themselves are insoluble molecules with direct toxic effects on cells. AGE formation of SOD1 composing the granule-coated fibrils (probable AGE-modified mutant SOD1) may amplify their aggregation and produce a more marked toxicity. (ALS 2000; 1:163-184)


Journal of Neuropathology and Experimental Neurology | 1996

Familial Amyotrophic Lateral Sclerosis with a Two Base Pair Deletion in Superoxide Dismutase 1 Gene: Multisystem Degeneration with Intracytoplasmic Hyaline Inclusions in Astrocytes

Shinsuke Kato; Masaru Shimoda; Yasuhiro Watanabe; Kenji Nakashima; Kazuro Takahashi; Eisaku Ohama

We performed a comparative neuropathological study on two siblings with familial amyotrophic lateral sclerosis (FALS). The clinical course of the sister who died at age 46 was 18 months, and that of the brother who died at age 65, 11 years. The neuropathological findings of the female were compatible with FALS with posterior column involvement. Her brother had multisystem degeneration in addition to the motor neuron disturbance; Lewy body-like hyaline inclusions (LBHIs) were present in the affected neurons of the degenerative lesions. Eosinophilic inclusions were seen in many astrocytes of the affected areas of the male FALS patient. Immunohistochemical assays revealed that most astrocytic inclusions reacted with the antibodies against Cu/Zn-superoxide dismutase 1 (SOD1) and ubiquitin; immunoreactivity was essentially the same as that of the neuronal LBHIs. Ultrastructurally the astrocytic inclusions were composed mainly of 15- to 25-nm granule-coated fibrils and granular material, resembling LBHIs of the neurons. Despite the dissimilar neuropathological features, both patients had the same two base pair deletion in exon 5 of the SOD1 gene. These findings suggest that FALS due to an SOD1 gene mutation is potentially a multisystem degenerative disorder, affecting not only neurons, but also astrocytes.


Acta Neuropathologica | 2006

Fragmentation of Golgi apparatus of nigral neurons with α-synuclein-positive inclusions in patients with Parkinson’s disease

Yukio Fujita; Eisaku Ohama; Masamitsu Takatama; Safa Al-Sarraj; Koichi Okamoto

We examined whether the Golgi apparatus (GA) is fragmented in nigral neurons in 18 cases with Parkinson’s disease (PD) and in 8 control cases. The nigral neurons in cases with PD showed various degrees of Lewy pathology with α-synuclein immunohistochemistry, and we divided the neurons into three subtypes according to differences in α-synuclein immunoreactivity: (1) neurons without pale bodies or Lewy bodies, (2) neurons with pale bodies, and (3) neurons with Lewy bodies. In controls, we did not observe fragmented GA in nigral neurons by immunocytochemistry with an anti-TGN46 antibody. In PD, the GA was fragmented in 3% of the nigral neurons without inclusions, and in 5% of the neurons with Lewy bodies. In contrast, fragmented GA was noted in 19% of the neurons containing pale bodies. Since pale bodies represent early stages in the development of brainstem Lewy bodies, our results suggest that the cytotoxicity of α-synuclein-positive aggregates is reduced in the process of Lewy body formation.


Acta Neuropathologica | 2000

Advanced glycation endproduct-modified superoxide dismutase-1 (SOD1)-positive inclusions are common to familial amyotrophic lateral sclerosis patients with SOD1 gene mutations and transgenic mice expressing human SOD1 with a G85R mutation.

Shinsuke Kato; Seiko Horiuchi; Jian Liu; Don W. Cleveland; Noriyuki Shibata; Kenji Nakashima; Ryoji Nagai; Asao Hirano; Miki Takikawa; Masako Kato; Imaharu Nakano; Eisaku Ohama

Abstract To clarify the biological significance of the neuronal Lewy body-like hyaline inclusions and astrocytic hyaline inclusions characteristically found in patients with familial amyotrophic lateral sclerosis with superoxide dismutase-1 (SOD1) gene mutations and in transgenic mice expressing human SOD1 with G85R mutation, the detailed protein composition in both types of inclusions was immunohistochemically analyzed using 45 different antibodies. Both types of inclusions had very strong immunoreactivity for SOD1. The SOD1-positive inclusions in both cell types were also immunoreactive for the insoluble advanced glycation endproducts (AGEs) such as Nɛ-(carboxymethyl)lysine (CML), pyrraline and pentosidine: both inclusions in both conditions were ultrastructurally composed of the granule-coated fibrils that had immunoreactivities to CML and pyrraline. Both types of inclusions were negative for stress-response proteins (SRPs), 4-hydroxy-2-nonenal (HNE), acrolein, nitric oxide synthases (NOSs) and nitrotyrosine as representative markers of oxidative stress. The neurons and astrocytes of the normal individuals and non-transgenic mice showed no significant immunoreactivity for SOD1, AGEs, SRPs, HNE, acrolein, NOSs or nitrotyrosine. Our results suggest that a portion of the SOD1 composing both type of inclusions, probably toxic mutant SOD1, is modified by the AGEs, and that the formation of the AGE-modified SOD1 is one of the mechanisms responsible for the aggregation involving no significant oxidative mechanisms.


Neuropathology and Applied Neurobiology | 1992

Comparative immunohistochemical study on the expression of αB crystallin, ubiquitin and stress-response protein 27 in ballooned neurons in various disorders

S. Kato; Asao Hirano; T. Umahara; M. Kato; Fritz Herz; Eisaku Ohama

This Report deals with a comparative study on the expression of αB crystallin, ubiquitin, stress‐response protein 27 (srp 27), srp 72 and phosphorylated neurofilament protein (pNFP) by ballooned neurons in Picks disease, Creutzfeldt‐Jakob disease (CJD), amyotrophic lateral sclerosis (ALS), leptomeningeal carcinomatosis, anterior spinal artery syndrome and pellagra. Immunohistochemical techniques were used. αB Crystallin was expressed by the majority of ballooned neurons of Picks disease and CJD, but not by those of the other disorders. Ubiquitin and srp 27 expression was also restricted to abnormal neurons of Picks disease and CJD, but the proportion of stained cells was less than that expressing aB‐crystallin. There was no evidence of ballooned neurons expressing srp 72. Except for those of pellagra patients, phosphorylated neurofilament protein (pNFP) was detected in most abnormal neurons. Our results suggest that the mechanisms involved in formation and maintenance of swollen neurons in Picks disease and CJD may be different than those of ballooned neurons in the other entities studied.


Acta Neuropathologica | 1992

Ultrastructural and immunohistochemical studies on ballooned cortical neurons in Creutzfeldt-Jakob disease: expression of αB-crystallin, ubiquitin and stress-response protein 27

S. Kato; Asao Hirano; T. Umahara; Josefina F. Llena; Fritz Herz; Eisaku Ohama

SummaryThis report concerns ultrastructural and immunohistochemical studies on ballooned neurons of ten patients with Creutzfeldt-Jakob disease (CJD). While abundant ballooned neurons and severe white matter degeneration was seen in six Japanese cases, only occasional ballooned neurons and no white matter degeneration was observed in four cases from the files of Montefiore Medical Center. Ultrastructurally, the ballooned neurons contained granule-coated fibrils of 25 to 40 nm in width and 10-nm neurofilaments. The immunohistochemical studies revealed that most ballooned neurons expressed αB-crystallin, with deposits of reaction products observed in the cytoplasm. A similar intracellular staining pattern was also seen with the antibody to phosphorylated neurofilament proteins (pNFP). Although the proportion of stained ballooned neurons was less, a positive reaction was also observed with antibodies against ubiquitin, stress-response protein 27 (srp 27) and synptophysin, but not with an antibody to srp 72. Our findings suggest that expression of pNFP and synaptophysin by ballooned neurons may reflect axonal impairment and that the presence of αB-crystallin, srp 27 and ubiquitin may be related to the degenerative processes that neurons undergo in CJD.


Acta Neuropathologica | 2004

Expression of ubiquitin-binding protein p62 in ubiquitin-immunoreactive intraneuronal inclusions in amyotrophic lateral sclerosis with dementia: analysis of five autopsy cases with broad clinicopathological spectrum

Toshiya Nakano; Kazuhiro Nakaso; Kenji Nakashima; Eisaku Ohama

Amyotrophic lateral sclerosis with dementia (ALSD), corresponding to the motor neuron disease type of frontotemporal dementia, is neuropathologically characterized by depletion of the motor neurons, degeneration of the extra-motor cerebral cortices and formation of ubiquitin-immunoreactive (not argyrophilic, tau-negative, α-synuclein-negative) intraneuronal inclusions. Recently, immunoreactivity for ubiquitin-binding protein p62 has been reported in several ubiquitin-containing intraneuronal or intraglial inclusions (e.g. neurofibrillary tangles, Pick bodies, Lewy bodies, glial cytoplasmic inclusions) in various neurodegenerative diseases. We examined p62 immunoreactivity in ubiquitin-immunoreactive intraneuronal inclusions in five ALSD cases with a broad clinicopathological spectrum. p62 immunoreactivity in ubiquitin-immunoreactive intraneuronal inclusions was seen in all cases. The mean proportion of p62-immunoreactive inclusions to the total number of ubiquitin-immunoreactive inclusions (p62/Ub ratio) in the dentate gyrus was 27.5±16.6% (range 6.3–47.3%). There was no correlation between p62/Ub ratio and the severity of dementia, duration of illness or neuropathological severity. Although the main constituent of these inclusions is unknown, our study suggests that p62 contributes to the formation of the inclusions via the same mechanism as in other previously reported neurodegenerative diseases. Since p62 is believed to have a neuroprotective role, the formation of these inclusions may represent a non-harmful, rather protective effect against the neuronal degeneration in ALSD.


European Journal of Neuroscience | 2005

Pro-apoptotic protein glyceraldehyde-3-phosphate dehydrogenase promotes the formation of Lewy body-like inclusions.

Katsumi Tsuchiya; Hisao Tajima; Toyoyasu Kuwae; Takao Takeshima; Toshiya Nakano; Masaharu Tanaka; Katsuyoshi Sunaga; Yoko Fukuhara; Kenji Nakashima; Eisaku Ohama; Hideki Mochizuki; Yoshikuni Mizuno; Nobuo Katsube; Ryoichi Ishitani

Glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) has long been recognized as a classical glycolytic protein; however, previous studies by our group and others have demonstrated that GAPDH is a general mediator initiating one or more apoptotic cascades. Our most recent findings have elucidated that an expression of a pro‐apoptotic protein GAPDH is critically regulated at the promoter region of the gene. Apoptotic signals for its subsequent aggregate formation and nuclear translocation are controlled by the respective functional domains harboured within its cDNA component. In this study, coexpression of GAPDH with either wild‐type or mutant (A53T) α‐synuclein and less likely with β‐synuclein in transfected COS‐7 cells was found to induce Lewy body‐like cytoplasmic inclusions. Unlike its full‐length construct, the deleted mutant GAPDH construct (C66) abolished these apoptotic signals, disfavouring the formation of inclusions. The generated inclusions were ubiquitin‐ and thioflavin S‐positive appearing fibrils. Furthermore, GAPDH coimmunoprecipitated with wild‐type α‐synuclein in this paradigm. Importantly, immunohistochemical examinations of post mortem materials from patients with sporadic Parkinsons disease revealed the colocalized profiles immunoreactive against these two proteins in the peripheral zone of Lewy bodies from the affected brain regions (i.e. locus coeruleus). Moreover, a quantitative assessment showed that about 20% of Lewy bodies displayed both antigenicities. These results suggest that pro‐apoptotic protein GAPDH may be involved in the Lewy body formation in vivo, probably associated with the apoptotic death pathway.


Acta Neuropathologica | 2001

Copper chaperone for superoxide dismutase co-aggregates with superoxide dismutase 1 (SOD1) in neuronal Lewy body-like hyaline inclusions : an immunohistochemical study on familial amyotrophic lateral sclerosis with SOD1 gene mutation

Shinsuke Kato; Hisae Sumi-Akamaru; Harutoshi Fujimura; Saburo Sakoda; Masako Kato; Asao Hirano; Miki Takikawa; Eisaku Ohama

Abstract. The copper chaperone for superoxide dismutase (CCS) interacts with Cu/Zn-binding superoxide dismutase 1 (SOD1) specifically and delivers copper to SOD1. To determine the role of the CCS-SOD1 interaction in the pathogenesis of SOD1-mutated familial amyotrophic lateral sclerosis (FALS) patients, we produced an affinity-purified rabbit antibody against CCS and investigated the immunohistochemical localization of both CCS and SOD1 in neuronal Lewy body-like hyaline inclusions (LBHIs) in the spinal cords of two FALS patients with a two-base pair deletion at codon 126 in the SOD1 gene and three FALS patients with an Ala to Val substitution at codon 4. The LBHIs in anterior horn cells from the five FALS patients showed identical immunoreactivities for CCS: the reaction product deposits with the antibody against CCS were generally restricted to the periphery of the core and halo-type LBHIs. The localizations of the immunoreactivities for CCS and SOD1 were similar in the inclusions: both CCS and SOD1 colocalized in neuronal LBHIs in the five mutant SOD1-linked FALS patients. Our results suggest that the specific interaction and aggregation of CCS-SOD1 (probably CCS-mutant SOD1) in SOD1-mutated FALS patients may amplify the formation of inclusions and emphasize a more marked mutant SOD1-mediated toxicity.


Neuroradiology | 2008

Putaminal lesion in multiple system atrophy: postmortem MR-pathological correlations

Eiji Matsusue; Shinya Fujii; Yoshiko Kanasaki; Shuji Sugihara; Hajime Miyata; Eisaku Ohama; Toshihide Ogawa

IntroductionPosterior putaminal atrophy, putaminal T2-hyper and/or hyposignal changes have been observed in patients with multiple system atrophy (MSA) with parkinsonism.MethodsPostmortem T2-weighted images were compared with histological findings in seven autopsy-proven cases of putaminal lesions of MSA. All cases were evaluated on 1.5T magnetic resonance imaging (MRI) scanners and three cases were evaluated on 3T scanners.ResultsThere were three types of putaminal changes: Type 1, mild putaminal atrophy and isointensity; Type 2, putaminal atrophy and diffuse hyperintensity with a hyperintense putaminal rim (HPR); Type 3, putaminal atrophy and iso-or-hypointensity with HPR. The signal intensities of the putamen in Types 1 and 3 were more hypointense on 3T images than on 1.5T images. In Type 1, mild putaminal atrophy showed mild neuronal loss and gliosis and diffuse ferritin deposition. In Types 2 and 3, the areas of putaminal atrophy, severe in the posterior region, showed severe neuronal loss and gliosis, many pigments that were positive for ferritin and Fe 3+ and diffuse ferritin deposition. Although, tissue rarefaction was more severe in Type 2 than in Type 3, pigment deposition was more severe in Type 3. The HPR showed a severe loss of myelin and axons with tissue rarefaction of the external capsule or putaminal rim in Types 2 and 3.ConclusionPosterior putaminal atrophy reflects neuronal loss and gliosis. While putaminal iso-or -hypointensity reflects diffuse ferritin and Fe3+ deposition, hyperintensity reflects tissue rarefaction. The HPR reflects degeneration of the putaminal lateral margin and/or external capsule. These findings reflect characteristic histological findings of MSA with parkinsonism.

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Asao Hirano

Albert Einstein College of Medicine

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Kohtaro Asayama

University of Occupational and Environmental Health Japan

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