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1.
Acta Neuropathol ; 140(5): 695-713, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32803350

RESUMO

Mislocalization and abnormal deposition of TDP-43 into the cytoplasm (TDP-43 proteinopathy) is a hallmark in neurons of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). However, the pathogenic mechanism of the diseases linked to TDP-43 is largely unknown. We hypothesized that the failure of mRNA transport to neuronal axons by TDP-43 may contribute to neurodegeneration in ALS and FTLD, and sought to examine the function of TDP-43 by identifying its target mRNA for axonal transport. We found that mRNAs related to translational function including ribosomal proteins (RPs) were decreased by shRNA-based TDP-43 knock-down in neurites of cortical neurons. TDP-43 binds to and transports the RP mRNAs through their 5' untranslated region, which contains a common 5' terminal oligopyrimidine tract motif and a downstream GC-rich region. We showed by employing in vitro and in vivo models that the RP mRNAs were translated and incorporated into native ribosomes locally in axons to maintain functionality of axonal ribosomes, which is required for local protein synthesis in response to stimulation and stress to axons. We also found that RP mRNAs were reduced in the pyramidal tract of sporadic ALS cases harboring TDP-43 pathology. Our results elucidated a novel function of TDP-43 to control transport of RP mRNAs and local translation by ribosomes to maintain morphological integrity of neuronal axons, and proved the influence of this function of TDP-43 on neurodegeneration in ALS and FTLD associated with TDP-43 proteinopathy.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Biossíntese de Proteínas/fisiologia , Transporte Proteico/fisiologia , RNA Mensageiro/metabolismo , Proteínas Ribossômicas/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Animais , Axônios/metabolismo , Axônios/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/patologia , Proteinopatias TDP-43/metabolismo , Proteinopatias TDP-43/patologia
2.
Proc Natl Acad Sci U S A ; 114(45): E9645-E9654, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29042514

RESUMO

Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by pathology of accumulated amyloid ß (Aß) and phosphorylated tau proteins in the brain. Postmortem degradation and cellular complexity within the brain have limited approaches to molecularly define the causal relationship between pathological features and neuronal dysfunction in AD. To overcome these limitations, we analyzed the neuron-specific DNA methylome of postmortem brain samples from AD patients, which allowed differentially hypomethylated region of the BRCA1 promoter to be identified. Expression of BRCA1 was significantly up-regulated in AD brains, consistent with its hypomethylation. BRCA1 protein levels were also elevated in response to DNA damage induced by Aß. BRCA1 became mislocalized to the cytoplasm and highly insoluble in a tau-dependent manner, resulting in DNA fragmentation in both in vitro cellular and in vivo mouse models. BRCA1 dysfunction under Aß burden is consistent with concomitant deterioration of genomic integrity and synaptic plasticity. The Brca1 promoter region of AD model mice brain was similarly hypomethylated, indicating an epigenetic mechanism underlying BRCA1 regulation in AD. Our results suggest deterioration of DNA integrity as a central contributing factor in AD pathogenesis. Moreover, these data demonstrate the technical feasibility of using neuron-specific DNA methylome analysis to facilitate discovery of etiological candidates in sporadic neurodegenerative diseases.


Assuntos
Doença de Alzheimer/genética , Proteína BRCA1/genética , Epigênese Genética/genética , Neurônios/metabolismo , Proteínas tau/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/metabolismo , Dano ao DNA/genética , Metilação de DNA/genética , Modelos Animais de Doenças , Humanos , Plasticidade Neuronal/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais/genética , Regulação para Cima/genética
3.
Brain ; 141(2): 486-495, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253086

RESUMO

Missense mutations in leucine-rich repeat kinase 2 (LRRK2) are pathogenic for familial Parkinson's disease. However, it is unknown whether levels of LRRK2 protein in the brain are altered in patients with LRRK2-associated Parkinson's disease. Because LRRK2 mutations are relatively rare, accounting for approximately 1% of all Parkinson's disease, we accessioned cases from five international brain banks to investigate levels of the LRRK2 protein, and other genetically associated Parkinson's disease proteins. Brain tissue was obtained from 17 LRRK2 mutation carriers (12 with the G2019S mutation and five with the I2020T mutation) and assayed by immunoblot. Compared to matched controls and idiopathic Parkinson's disease cases, we found levels of LRRK2 protein were reduced in the LRRK2 mutation cases. We also measured a decrease in two other proteins genetically implicated in Parkinson's disease, the core retromer component, vacuolar protein sorting associated protein 35 (VPS35), and the lysosomal hydrolase, glucocerebrosidase (GBA). Moreover, the classical retromer cargo protein, cation-independent mannose-6-phosphate receptor (MPR300, encoded by IGF2R), was also reduced in the LRRK2 mutation cohort and protein levels of the receptor were correlated to levels of LRRK2. These results provide new data on LRRK2 protein expression in brain tissue from LRRK2 mutation carriers and support a relationship between LRRK2 and retromer dysfunction in LRRK2-associated Parkinson's disease brain.


Assuntos
Encéfalo/metabolismo , Regulação da Expressão Gênica/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Mutação/genética , Doença de Parkinson , Idoso , Idoso de 80 Anos ou mais , Catepsina D/metabolismo , Diagnóstico , Feminino , Humanos , Proteínas de Membrana Lisossomal/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Fosforilação/genética , ATPases Translocadoras de Prótons/metabolismo , Receptor IGF Tipo 2/metabolismo , Proteínas de Transporte Vesicular/metabolismo , alfa-Sinucleína/metabolismo , beta-Glucosidase/metabolismo
4.
Neuropathology ; 38(2): 171-178, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28906030

RESUMO

Transactivation response DNA-binding protein 43 kDa (TDP-43) is a key protein of sporadic amyotrophic lateral sclerosis (ALS), and phosphorylated form of TDP-43 (p-TDP-43) is a major pathological protein that accumulates in sporadic ALS. p-TDP-43 is found not only in primary motor neurons, but often propagates to non-motor systems as well. However, pallido-nigro-luysian (PNL) degeneration (PNLD) is rarely associated with ALS. We describe here a 68-year-old ALS patient presenting severe PNLD. He had difficulty walking due to poor movement of his right leg, and was diagnosed as having Parkinson's disease because of akinesia. About 2 years after onset, weakness of his left hand and leg led to a diagnosis of ALS. Tube feeding and non-invasive positive-pressure ventilation were initiated. He died of respiratory failure at the age of 71. There was no family history of either neurological disorders or dementia. Neuropathological examination revealed severe loss of neurons and gliosis in the PNL system in addition to the upper and lower motor neuron system. p-TDP-43 pathology was widespread in the PNL and motor neuron systems and also in the amygdala and hippocampus where no significant gliosis or neuronal loss was detected. Synuclein pathology was not observed in the investigated areas. Immunoblot analysis of p-TDP-43 C-terminal fragments showed a type B band pattern consistent with sporadic ALS. This is the first case of ALS with PNLD, in which p-TDP-43 distribution was widespread in the hippocampal formation (Nishihira type 2 and Brettschneider stage 4), and the type B immunoblot pattern was confirmed. Our case indicated that the PNL system can be involved in the disease process in sporadic ALS cases, although rarely. We also reviewed previous autopsy cases of ALS with PNLD to clarify the clinicopathological features.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Proteínas de Ligação a DNA/metabolismo , Globo Pálido/metabolismo , Substância Negra/metabolismo , Núcleo Subtalâmico/metabolismo , Idoso , Células do Corno Anterior/patologia , Gliose/metabolismo , Gliose/patologia , Globo Pálido/patologia , Hipocampo/metabolismo , Humanos , Immunoblotting , Masculino , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Fosforilação , Substância Negra/patologia , Núcleo Subtalâmico/patologia
5.
Mov Disord ; 32(3): 423-432, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27911006

RESUMO

BACKGROUND: Leucine rich repeat kinase 2 (LRRK2) is a promising target for the treatment of Parkinson's disease; however, little is known about the expression of LRRK2 in human brain and if/how LRRK2 protein levels are altered in Parkinson's disease. OBJECTIVES: We measured the protein levels of LRRK2 as well as its phosphorylation on serines 910, 935, and 973 in the postmortem brain tissue of Parkinson's disease patients and aged controls with and without Lewy bodies. METHODS: LRRK2 and its phosphorylation were measured by immunoblot in brain regions differentially affected in Parkinson's disease (n = 30) as well as subjects with Lewy bodies restricted to the periphery and lower brain stem (n = 25) and matched controls without pathology (n = 25). RESULTS: LRRK2 levels were increased in cases with restricted Lewy bodies, with a 30% increase measured in the substantia nigra. In clinical Parkinson's disease, levels of LRRK2 negatively correlated to disease duration and were comparable with controls. LRRK2 phosphorylation, however, particularly at serine 935, was reduced with clinical Parkinson's disease with a 36% reduction measured in the substantia nigra. CONCLUSIONS: Our data show that LRRK2 phosphorylation is reduced with clinical PD, whereas LRRK2 expression is increased in early potential prodromal stages. These results contribute to a better understanding of the role of LRRK2 in idiopathic Parkinson's disease and may aid efforts aimed at therapeutically targeting the LRRK2 protein. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Tonsila do Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Corpos de Lewy/metabolismo , Doença de Parkinson/metabolismo , Substância Negra/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia
6.
J Gastroenterol Hepatol ; 32(9): 1604-1610, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28142194

RESUMO

BACKGROUND AND AIM: In preceding studies, we identified that the myenteric plexus (MP) could be visualized with confocal laser endomicroscopy (CLE) by applying neural fluorescent probes lacking clinical safety profiling data from the submucosal side. In this study, we evaluated the technical feasibility of MP visualization using probe-based CLE (pCLE) from the serosal side with cresyl violet (CV), which has been used clinically for chromoendoscopy. METHODS: The dye affinity of CV for MP was first explored in an in vivo transgenic mouse model using neural crest derivatives labeled with green fluorescent protein. We also tested the feasibility of CV-assisted visualization of MP in human surgical specimens, wherein the tissue dying and pCLE observation were performed from the serosal side. In the human study, rate of MP visualization by pCLE was evaluated as the primary outcome. We also evaluated the sensitivity and specificity of MP visualization by pCLE, using pathological presence/absence of MP as the gold standard. RESULTS: We confirmed the dye affinity of CV to MP in all tested models. The MP appeared as brightly stained ladder-like structures with pCLE, and in the human study, MP was visualized in 12/14 (85.7%) samples, with 92.3% sensitivity and 100% specificity. In positive cases showing the ladder-like structure of MP by pCLE, the mean maximum and minimum widths of nerve strands were 54.3 (± 23.6) and 19.7 (± 6.0) µm, respectively. A ganglion was detected by pCLE in 10 cases (10/12, 83.3%). CONCLUSIONS: This study demonstrated the technical feasibility of visualizing the MP in real time by CV-assisted pCLE (UMIN-CTR number, UMIN000015056).


Assuntos
Microscopia Confocal/métodos , Plexo Mientérico/ultraestrutura , Adolescente , Animais , Benzoxazinas , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Corantes Fluorescentes , Proteínas de Fluorescência Verde , Humanos , Lactente , Masculino , Camundongos Transgênicos , Modelos Animais
8.
Clin Exp Nephrol ; 18(6): 844-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24463961

RESUMO

BACKGROUND: Sphingosine-1-phosphate (S1P) is reportedly involved in the pathogenesis of kidney disease; however, the precise role played by S1P in renal disorders still remains controversial. Rho kinase plays an important role in the development of diabetic nephropathy by inducing glomerular and tubulointerstitial fibrosis. Rho kinase is known to be stimulated by S1P through its specific receptor, S1P2 receptor (S1P2). Hence, we investigated whether S1P-S1P2 signaling plays a role in the epithelial-mesenchymal transition (EMT) through Rho kinase activation in renal tubules. METHOD: To characterize the distribution of the S1P2, an immunohistochemical examination of the receptor was performed in the kidney of the non-diabetic and diabetic mice. Next, we examined Rho kinase activity as well as E-cadherin and alpha-smooth muscle actin (α-SMA) expression by real-time RT-PCR and western blotting in cultured rat tubular epithelial cells under S1P stimulation with and without a Rho kinase inhibitor and an S1P2 blocker. In addition, the distribution of E-cadherin and α-SMA was examined by immunocytochemistry. RESULT: S1P2 was expressed mainly in the renal tubules; expression was intense in collecting ducts and distal tubules compared to other segments. S1P induced activation of Rho kinase through the S1P2, which changed the distribution of E-cadherin and increased the expression of α-SMA. CONCLUSION: Rho kinase activation by S1P via S1P2 initiated EMT changes in cultured renal tubular cells. Our results suggest that excessive stimulation of S1P might facilitate renal fibrosis via activation of Rho kinase through S1P2.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Túbulos Renais/patologia , Lisofosfolipídeos/farmacologia , Receptores de Lisoesfingolipídeo/fisiologia , Esfingosina/análogos & derivados , Quinases Associadas a rho/fisiologia , Actinas/fisiologia , Animais , Caderinas/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Células Epiteliais/patologia , Células Epiteliais/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Túbulos Renais/fisiologia , Masculino , Camundongos , Camundongos Knockout , Receptores para Leptina/deficiência , Receptores para Leptina/genética , Receptores para Leptina/fisiologia , Esfingosina/farmacologia
9.
Kidney Int ; 84(3): 545-54, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23615507

RESUMO

The small GTPase Rho and its effector Rho-kinase are involved in the pathogenesis of diabetic nephropathy. Accumulating evidence shows that hypoxia-inducible factor-1α (HIF-1α) is a key regulator of renal sclerosis under diabetic conditions. However, the interactions of Rho-kinase and HIF-1α in the development of renal dysfunction have not been defined. Here, we assessed whether Rho-kinase blockade attenuates HIF-1α induction and the subsequent fibrotic response using type 2 diabetic mice and cultured mesangial cells. Fasudil, a Rho-kinase inhibitor, reduced urinary albumin excretion, mesangial matrix expansion, and the expression of fibrotic mediators in db/db mice. Mechanistically, HIF-1α accumulation and the expression of its target genes that contribute to diabetic glomerulosclerosis were also prevented by fasudil in the renal cortex. In mesangial cells, Rho/Rho-kinase signaling was activated under hypoxic conditions. Further in vitro studies showed that pharmacological and genetic inhibition of Rho-kinase promoted proteasomal HIF-1α degradation, which subsequently suppressed HIF-1-dependent profibrotic gene expression by upregulation of prolyl hydroxylase 2. Thus, we found a previously unrecognized renoprotective mechanism for the effects of Rho-kinase inhibition and this could be a potential therapeutic target for the treatment of diabetic nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/prevenção & controle , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Albuminúria/metabolismo , Albuminúria/prevenção & controle , Animais , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Fibrose , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Córtex Renal/metabolismo , Córtex Renal/patologia , Masculino , Camundongos , Camundongos Mutantes , Inibidores de Proteínas Quinases/farmacologia , Quinases Associadas a rho/efeitos dos fármacos , Quinases Associadas a rho/metabolismo
10.
Hum Mol Genet ; 19(1): 181-95, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19843541

RESUMO

Post-translational modification by SUMO (small ubiquitin-like modifier) was proposed to modulate the pathogenesis of several neurodegenerative diseases. Spinocerebellar ataxia type 7 (SCA7) is a neurodegenerative disorder, whose pathology is caused by an expansion of a polyglutamine stretch in the protein ataxin-7 (ATXN7). Here, we identified ATXN7 as new target for SUMOylation in vitro and in vivo. The major SUMO acceptor site was mapped to lysine 257, which is part of an evolutionarily conserved consensus SUMOylation motif. SUMOylation did not influence the subcellular localization of ATXN7 nor its interaction with components of the TFTC/STAGA complex. Expansion of the polyglutamine stretch did not impair the SUMOylation of ATXN7. Furthermore, SUMO1 and SUMO2 colocalized with ATXN7 in a subset of neuronal intranuclear inclusions in the brain of SCA7 patients and SCA7 knock-in mice. In a COS-7 cellular model of SCA7, in addition to diffuse nucleoplasmic staining we identified two populations of nuclear inclusions: homogenous or non-homogenous. Non-homogenous inclusions showed significantly reduced colocalization with SUMO1 and SUMO2, but were highly enriched in Hsp70, 19S proteasome and ubiquitin. Interestingly, they were characterized by increased staining with the apoptotic marker caspase-3 and by disruption of PML nuclear bodies. Importantly, preventing the SUMOylation of expanded ATXN7 by mutating the SUMO site increased both the amount of SDS-insoluble aggregates and of caspase-3 positive non-homogenous inclusions, which act toxic to the cells. Our results demonstrate an influence of SUMOylation on the multistep aggregation process of ATXN7 and implicate a role for ATXN7 SUMOylation in SCA7 pathogenesis.


Assuntos
Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/toxicidade , Peptídeos/toxicidade , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Expansão das Repetições de Trinucleotídeos/genética , Adulto , Animais , Ataxina-7 , Caspase 3/metabolismo , Criança , Ativação Enzimática/efeitos dos fármacos , Evolução Fatal , Feminino , Humanos , Corpos de Inclusão Intranuclear/efeitos dos fármacos , Corpos de Inclusão Intranuclear/metabolismo , Lisina/metabolismo , Masculino , Camundongos , Complexos Multiproteicos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Quaternária de Proteína , Transporte Proteico/efeitos dos fármacos , Ataxias Espinocerebelares/metabolismo , Ataxias Espinocerebelares/patologia , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Ubiquitina/metabolismo
11.
Gastrointest Endosc ; 75(2): 405-10, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22248608

RESUMO

BACKGROUND: The submucosal tunneling technique enables us to endoscopically access deeper tissue layers. Use of probe-based confocal laser endomicroscopy (pCLE) provides optical histologic imaging on the site. OBJECTIVE: To determine the technical feasibility of ex vivo and in vivo pCLE imaging of the muscularis propria and myenteric neurons by using submucosal endoscopy with a mucosal flap safety valve (SEMF). DESIGN: Acute porcine model study. SETTING: Animal laboratory. INTERVENTION: Two ex vivo and 6 in vivo porcine models were used. A submucosal space was created with SEMF, and a neuronal molecular probe was topically applied onto the muscularis. Confocal imaging of the stained muscularis was performed by using pCLE. The selected sites were sampled, and the histopathology of the sites was analyzed. MAIN OUTCOME MEASUREMENTS: The two main outcome measures were the procedural success rate of submucosal access and the correlation between pCLE and histologic images. RESULTS: Submucosal access to the pCLE study site was successful in all attempts (100%; 17/17 sites). The muscularis propria was visualized with pCLE in the ex vivo and in vivo porcine models in 83.3% of sites (20/24), and the neuron-like cells were identified in 41.7% of sites (10/24). LIMITATIONS: Animal experiment. CONCLUSION: The muscularis propria and myenteric neurons could be selectively visualized with pCLE in vivo.


Assuntos
Endoscopia Gastrointestinal/métodos , Esôfago/anatomia & histologia , Mucosa Gástrica/anatomia & histologia , Microscopia Confocal , Neurônios/citologia , Estômago/anatomia & histologia , Animais , Esôfago/citologia , Esôfago/inervação , Mucosa Gástrica/citologia , Mucosa Gástrica/inervação , Plexo Mientérico , Estômago/citologia , Estômago/inervação , Suínos
12.
Neurobiol Dis ; 41(1): 33-42, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20732423

RESUMO

In spinocerebellar ataxia-7 (SCA7), a polyglutamine (polyQ) expansion in the ataxin-7 protein leads to the formation of neuronal intranuclear inclusions (NIIs) and neurodegeneration. In this study, amyloid precursor-like protein 2 (APLP2) was identified as a partner protein for ataxin-7. APLP2, belonging to the APP gene family, undergoes secretase and caspase cleavages and has been implicated in the pathogenesis of Alzheimer's disease (AD). Activated caspase-3 cleaves APP family proteins to release N-terminal fragments (NTFs) and intracellular C-terminal domains (ICDs), which can translocate into the nucleus and induce neurotoxicity in AD. Here, we report abnormal nuclear relocation of APLP2 and detection of NTFs in NIIs in SCA7. The ICDs generated by caspase-3 cleavage of APLP2 accumulate in nuclei and contribute to a cumulative toxicity when coexpressed with mutated ataxin-7. Our data suggest that the interaction between APLP2 and ataxin-7 and proteolytic processing of APLP2 may contribute to the pathogenesis of SCA7.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Corpos de Inclusão Intranuclear/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fragmentos de Peptídeos/metabolismo , Ataxias Espinocerebelares/metabolismo , Adulto , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/toxicidade , Animais , Ataxina-7 , Criança , Humanos , Corpos de Inclusão Intranuclear/patologia , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/toxicidade , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Células PC12 , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/toxicidade , Processamento de Proteína Pós-Traducional/genética , Ratos , Ataxias Espinocerebelares/etiologia , Ataxias Espinocerebelares/patologia
13.
Mol Genet Metab ; 102(2): 170-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21051253

RESUMO

Mucolipidosis type III (MLIII) is a mild form of Mucolipidosis type II (MLII, I-cell disease) of late onset, of which almost no pathological study has been reported, as it is a very rare disease. We encountered the case of a 23-year-old man of Japanese and Caucasian mixed parentage diagnosed with MLIII by enzyme assay and genotyping. He died suddenly due to severe dilated cardiomyopathy. On the day after his death, autopsy was performed, and accumulation of Luxol Fast Blue (LFB) positive material was found to be most severe in the neuronal cells of dorsal root ganglions (DRG). Electromicroscopic DRG revealed the neuronal cytoplasm was filled with a zebra-body-like membranous matrix. We tried immunohistochemistry to investigate the mechanism of such accumulation in the DRG that resulted in double positive anti-ubiquitin antibody (FK-2) and anti-LC3 antibody (as specific marker for autophagy) staining, and speculated activating of autophagosome pathway, and 'zebra-body' should be suspected as dysfunctional autophagosome. We also detected foamy cell proliferation in the dura mater, Auerbach's plexus (peripheral nervous system), podocytes of almost all glomeruli, cartilage tissue in lumbar discs, and in cardiac muscle. We tried FK-2 and anti-LC3 antibody staining also for the podocytes, the area with the most marked proliferation of foamy cells, but the result was negative. This led us to speculate that these pathological findings, namely, accumulation of LFB-positive material and foamy fibroblast proliferation, might be the forms of dysfunctional autophagosome at various stages of development. This pathological study of MLIII supports the theory that MLIII is a mild type of MLII because of the close similarity of their pathological findings.


Assuntos
Autofagia , Mucolipidoses/diagnóstico , Mucolipidoses/patologia , Adulto , Autopsia , Encéfalo/patologia , Evolução Fatal , Humanos , Masculino , Mucolipidoses/terapia , Adulto Jovem
14.
Neuropathology ; 29(4): 472-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18992010

RESUMO

We describe the pathological features of a spinal cord biopsy from a 69-year-old woman with anti-aquaporin-4 antibody-negative recurrent longitudinal myelitis. Spinal cord MRI showed T2 high-intensity lesions with strong gadolinium enhancement, when episodes of sensory-motor impairment were repeated. The radiological abnormality was corrected by corticosteroid administration, but improvement of the symptoms was minimal. Although the patient had sicca symptoms and fulfilled four of the diagnostic criteria for Sjögren syndrome, the diagnosis was excluded, because of infection with hepatitis C virus, an exclusion criterion of Sjögren syndrome. In the spinal cord lesions, necrotic changes affected both myelin and axons. Infiltrating lymphocytes were predominantly T-cells. The proliferation of small vessels with hyalinization and concomitant occlusive change was remarkable. These pathological findings resembled those previously reported in Sjögren syndrome. Ultrastructurally, the endothelial cells of the small vessels showed features of activated cells and contained vesiculo-tubular structures in the cytoplasm, indicating that increased blood-brain barrier (BBB) permeability might contribute to pathogenesis. We speculated that increased BBB permeability and T-cell entry in the spinal parenchyma triggered pathological reactions resulting in necrotic changes in the spinal cord. Obstruction of small vessels might add ischemic damage to the lesions. The clinical course and pathological findings indicated that damage progressed rapidly in the spinal cord and was irreversible. The lesions apparently differed from typical demyelination plaques. Faced with such spinal cord lesions, a preventive therapeutic approach is necessary to avoid attack-associated disability.


Assuntos
Anticorpos , Aquaporina 4/imunologia , Hepatite C/sangue , Mielite/sangue , Síndrome de Sjogren/sangue , Medula Espinal/patologia , Idoso , Anticorpos/sangue , Aquaporina 4/sangue , Feminino , Hepacivirus , Hepatite C/patologia , Humanos , Mielite/patologia , Mielite/virologia , Recidiva , Síndrome de Sjogren/patologia , Síndrome de Sjogren/virologia , Medula Espinal/virologia
15.
Ann Nucl Med ; 33(6): 375-382, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30796626

RESUMO

OBJECTIVE: Amyloid-ß plaques and neurofibrillary tangles composed of tau protein are the neuropathological hallmarks of Alzheimer's disease. In recent years, marked progress has been made in Alzheimer's disease research using tau ligands for positron emission tomography (PET). However, the issue of off-target binding, that is, the binding of ligands to regions without tau pathology, remains unresolved. Tissues with melanin-containing cells (MCCs) have been suggested as binding targets for tau ligands. In the present study, we characterized the MCC-binding properties of representative tau PET ligands. METHODS: Autoradiographic studies of [18F]AV-1451 and [18F]THK5351 were conducted using postmortem human midbrain sections. Saturation-binding assays of [18F]AV-1451 and [18F]THK5351 were performed with B16F10 melanoma cells. The blocking effects of 25 compounds against [18F]THK5351 binding to B16F10 cells were used to investigate the relationship between chemical structure and MCC binding. RESULTS: Autoradiography demonstrated specific binding of the radioligands in the substantia nigra. [18F]AV-1451 and [18F]THK5351 exhibited saturable binding to melanoma cells ([18F]AV-1451: Kd = 669 ± 196 nM, Bmax = 622 ± 269 pmol/mg protein; [18F]THK5351: Kd = 441 ± 126 nM, Bmax = 559 ± 75.5 pmol/mg protein). In blocking studies with melanoma cells, compounds bearing multiple aromatic rings and an aminopyridine group, including tau ligands such as AV-1451, PBB3, and a lead compound of MK-6240, exhibited the inhibition of [18F]THK5351 binding comparable to self-blocking by THK5351 (> 70% at 10 µM). CONCLUSIONS: These studies suggest that the binding properties of [18F]AV-1451 and [18F]THK5351 are sufficient to expect highlighting of tissues with a high density of MCCs. The findings of the present study should aid the development of neuroimaging ligands that do not bind to MCC.


Assuntos
Melaninas/metabolismo , Tomografia por Emissão de Pósitrons , Proteínas tau/metabolismo , Aminopiridinas/metabolismo , Autorradiografia , Sítios de Ligação , Carbolinas/metabolismo , Linhagem Celular , Humanos , Quinolinas/metabolismo
16.
Acta Neurol Belg ; 108(3): 112-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19115677

RESUMO

The authors describe a case of rhabdoid meningioma (RM) in a 17-year-old boy that was determined by measuring the tumor volume during preoperative follow-up. The volume of the tumor located in the left occipital lobe, was measured every 1-5 months, using an image analysis software. The tumor volume doubling time (Td) ranged from 1.0 to 4.9 years in the first 11 months, but became 0.3 years in the last two months. The tumor grew rapidly in the last two months at which time surgery was performed. Pathological examination of the surgical specimen showed that the tumor contained rhabdoid cells (RCs). RCs were heterogeneously distributed in the tumor admixed with spindle-shaped cells. The areas where RCs were predominant had malignant histological features, with necrosis and high proliferation indices, whereas the areas with few RCs lacked the malignant features. The tumor grew slowly in the initial phase, possibly because components with low proliferation rates occupied most of the tumor. The tumor began to grow rapidly when the malignant component containing abundant RCs became predominant. To the authors' knowledge, this is the first report monitoring the volumetric change of RM periodically. Our investigation indicated that volumetric analysis is useful to decide surgical intervention of the meningiomas with potential malignancy.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , Tumor Rabdoide/patologia , Adolescente , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Cuidados Pré-Operatórios , Tumor Rabdoide/cirurgia , Fatores de Tempo , Carga Tumoral
17.
Geriatr Gerontol Int ; 18(2): 211-215, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28914998

RESUMO

AIM: We aimed to clarify the characteristics of malignancies in older adults focusing on distant metastasis in the whole body. METHODS: We retrospectively evaluated 7710 cases of autopsies (4011 men, 3699 women, median age of 80 years), and analyzed the characteristics of metastasis of adenocarcinoma, squamous cell carcinoma and urothelial carcinoma in each organ. RESULTS: The total number of cases with adenocarcinoma, squamous cell carcinoma or urothelial carcinoma was 2856, and most of them were adenocarcinomas. Among them, 1604 had metastatic lesions, and patients with metastasis were younger than those without metastasis. The major primary organs of adenocarcinoma were the stomach, colon, lung, prostate, gallbladder and pancreas, whereas those for squamous cell carcinoma were the lung, esophagus and uterus. Urothelial carcinoma cases were found in the urinary bladder, kidney and ureter. Metastatic adenocarcinomas mainly originated from the stomach, colon, lung, pancreas and gallbladder. Metastatic squamous cell carcinomas were from the lung, esophagus and uterus, whereas the kidney, bladder and ureter were the primary origins of metastatic urothelial carcinomas. Squamous cell carcinoma showed the highest incidence of metastasis, suggestive of it being of an aggressive phenotype. Furthermore, metastatic ability and the preferred metastatic sites varied among primary organs. CONCLUSIONS: We revealed an accurate incidence and the characteristics of metastatic cancer in a large-scale autopsy study of older Japanese patients from one institution. Identifying these features might prompt screening for malignancies, and consequently improve quality of life for older adults. Geriatr Gerontol Int 2018; 18: 211-215.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células de Transição/patologia , Metástase Neoplásica/patologia , Neoplasias Ureterais/patologia , Idoso , Idoso de 80 Anos ou mais , Autopsia , Feminino , Humanos , Japão , Masculino , Estudos Retrospectivos
18.
Geriatr Gerontol Int ; 18(10): 1507-1512, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30095207

RESUMO

AIM: The telomere is a structure present at the ends of chromosomes, and is known to shorten with aging and successive rounds of cell division. However, very little is known about telomere attrition in post-mitotic cells, such as neurons. METHODS: Using our originally developed quantitative fluorescence in situ hybridization method, we analyzed age-dependent alterations of telomere length in three types of cells in the human cerebrum: neurons and glial cells in both the gray and white matter. RESULTS: In adults, telomeres were significantly longer in neurons than in glial cells, whereas in infants, telomere lengths did not differ among the three cell types. No aging-related telomere attrition was evident in neurons. However, the telomeres of glial cells were shorter in older individuals than in younger individuals, and attrition was more rapid in the white matter than in the gray matter. CONCLUSIONS: The present results suggest that the telomeres of neurons remain stable throughout life, whereas telomeres in white matter glial cells become significantly shorter with age. Examination of adults showed no significant correlation between telomere length and age in the three cell types. Although the present study was cross-sectional, the results suggest that telomere shortening before adolescence contributes to the significant decrease of telomere length in white matter glial cells. The present findings in normal cerebral tissues will be informative for future studies of telomere stability in the diseased brain. Geriatr Gerontol Int 2018; 18: 1507-1512.


Assuntos
Envelhecimento/genética , Longevidade/genética , Neuroglia/patologia , Neurônios/patologia , Telômero/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Células Cultivadas , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Fatores de Risco , Sensibilidade e Especificidade , Técnicas de Cultura de Tecidos
19.
J Neuropathol Exp Neurol ; 76(7): 585-594, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28863453

RESUMO

Neuronal intranuclear hyaline inclusion disease (NIHID) is a neurodegenerative disorder characterized by the presence of eosinophilic nuclear inclusions (NIs) in diverse cell lines in systemic organs. Adult-onset NIHID typically manifests with dementia associated with leukoencephalopathy. The detection of NIs in skin biopsies is useful for an antemortem diagnosis. A previous analysis suggested that NIs in NIHID originated from nuclear bodies (NBs), an important nuclear domain related to the ubiquitin-p62-mediated protein degradation system. In this study, we analyzed skin samples from 5 NIHID and 5 control cases immunohistochemically and electron microscopically. In the control cases, small but significant amounts of ubiquitin- and p62-positive intranuclear structures were found. These structures were consistently colocalized with promyelocytic leukemia protein (PML), an essential component of NBs, in particular when activated. The p62- and PML-positive structures were more frequently found in NIHID cases. Activated NBs, having a core and a shell, were observed by electron microscopy in control but not in NIHID cases. Instead, immature and mature filamentous NIs were found only in the NIHID cases. Our results indicate that NBs could not be normally activated in the NIHID, and an abnormal alteration of NBs might be related to the pathogenesis of NIHID.


Assuntos
Corpos de Inclusão Intranuclear/metabolismo , Doenças Neurodegenerativas/patologia , Proteína da Leucemia Promielocítica/metabolismo , Proteína Sequestossoma-1/metabolismo , Pele/patologia , Idade de Início , Idoso , Diagnóstico , Eosinofilia/complicações , Eosinofilia/patologia , Feminino , Humanos , Corpos de Inclusão Intranuclear/patologia , Corpos de Inclusão Intranuclear/ultraestrutura , Imageamento por Ressonância Magnética , Masculino , Microscopia Eletrônica de Transmissão , Doenças Neurodegenerativas/diagnóstico por imagem , Escalas de Graduação Psiquiátrica , Pele/ultraestrutura , Estatísticas não Paramétricas
20.
Case Rep Gastroenterol ; 11(3): 545-553, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033776

RESUMO

Carbohydrate antigen 19-9 (CA19-9) is a well-known tumor marker for pancreatobiliary cancer, and several studies have shown that an elevated serum CA19-9 level is associated with more aggressive biological behavior in gastric cancer (GC). However, the clinicopathological characteristics of CA19-9-positive GC remain unclear. We herein report an autopsy case of CA19-9-positive GC in an 84-year-old man who was admitted to our hospital because of paralysis and anemia. Autopsy revealed an ulcerative-invasive tumor measuring 72 × 60 mm in the anterior wall of the gastric body. The tumor had invaded beyond the muscularis propria, and metastasized to the lung, liver, and regional lymph nodes. Histologically, the tumor cell had oval nuclei with abundant clear cytoplasm, and tubular and/or papillary features with prominent lymphovascular permeation and perineural invasion, mimicking pancreatobiliary carcinoma. Immunohistochemically, the tumor cells showed diffuse immunopositivity for CA19-9 and carcinoembryonic antigen. According to a review of cases reported in the literature, CA19-9-positive GCs show clinicopathological characteristics such as antral location, ulcerative-infiltrating gross feature, differentiated histology, prominent lymphatic and venous invasion, higher proportion of metastasis, and higher clinical stage. These results suggest that CA19-9-positive GC is pathologically a distinctive type of tumor with aggressive biological behavior.

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