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1.
Oncogene ; 36(26): 3740-3748, 2017 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-28192407

RESUMEN

TTF-1, also known as NKX2-1, is a transcription factor that has indispensable roles in both lung development and physiology. We and others have reported that TTF-1 frequently exhibits high expression with increased copy number in lung adenocarcinomas, and also has a role as a lineage-survival oncogene through transcriptional activation of crucial target genes including ROR1 and LMO3. In the present study, we employed a global proteomic search for proteins that interact with TTF-1 in order to provide a more comprehensive picture of this still enigmatic lineage-survival oncogene. Our results unexpectedly revealed a function independent of its transcriptional activity, as TTF-1 was found to interact with DDB1 and block its binding to CHK1, which in turn attenuated ubiquitylation and subsequent degradation of CHK1. Furthermore, TTF-1 overexpression conferred resistance to cellular conditions under DNA replication stress (RS) and prevented an increase in consequential DNA double-strand breaks, as reflected by attenuated induction of pCHK2 and γH2AX. Our findings suggest that the novel non-transcriptional function of TTF-1 identified in this study may contribute to lung adenocarcinoma development by conferring tolerance to DNA RS, which is known to be inherently elicited by activation of various oncogenes.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Replicación del ADN/fisiología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Roturas del ADN de Doble Cadena , ADN de Neoplasias/biosíntesis , ADN de Neoplasias/genética , Humanos , Neoplasias Pulmonares/patología , Factores de Transcripción , Transcripción Genética , Ubiquitinación
2.
Comput Vis Image Underst ; 148: 193-200, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27375348

RESUMEN

Adults with Autism Spectrum Conditions (ASC) experience marked difficulties in recognising the emotions of others and responding appropriately. The clinical characteristics of ASC mean that face to face or group interventions may not be appropriate for this clinical group. This article explores the potential of a new interactive technology, converting text to emotionally expressive speech, to improve emotion processing ability and attention to faces in adults with ASC. We demonstrate a method for generating a near-videorealistic avatar (XpressiveTalk), which can produce a video of a face uttering inputted text, in a large variety of emotional tones. We then demonstrate that general population adults can correctly recognize the emotions portrayed by XpressiveTalk. Adults with ASC are significantly less accurate than controls, but still above chance levels for inferring emotions from XpressiveTalk. Both groups are significantly more accurate when inferring sad emotions from XpressiveTalk compared to the original actress, and rate these expressions as significantly more preferred and realistic. The potential applications for XpressiveTalk as an assistive technology for adults with ASC is discussed.

3.
Osteoarthritis Cartilage ; 24(7): 1284-91, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26915639

RESUMEN

OBJECTIVE: In a rat monoiodoacetic acid (MIA)-induced arthritis model, the amount of MIA commonly used was too high, resulting in rapid bone destruction. We examined the effect of MIA concentrations on articular cartilage and infrapatellar fat pad (IFP). We also established an original system for "macroscopic cartilage and bone score" and "IFP inflammation score" specific to the rat MIA-induced arthritis model. DESIGN: Male Wistar rats received a single intra-articular injection of MIA in the knee. The amount of MIA was 0.1, 0.2, 0.5, and 1 mg respectively. Articular cartilage was evaluated at 2-12 weeks. IFP was also observed at 3-14 days. RESULTS: Macroscopically, low MIA doses induced punctate depressions on the cartilage surface, and cartilage erosion proceeded slowly over 12 weeks, while higher MIA doses already induced cartilage erosion at 2 weeks, followed by bone destruction. MIA macroscopic cartilage and bone score, OARSI histological score, and Mankin score increased in a dose- and time-dependent manner. The IFP inflammation score peaked at 5 days in low dose groups, then decreased, while in high dose groups, the IFP score continued to increase over 14 days due to IFP fibrosis. CONCLUSIONS: Punctate depressions, cartilage erosion, and bone destruction were observed in the MIA-induced arthritis model. The macroscopic cartilage and bone scoring enabled the quantification of cartilage degeneration and demonstrated that MIA-induced arthritis progressed in a dose- and time-dependent manner. IFP inflammation scores revealed that 0.2 mg MIA induced reversible synovitis, while 1 mg MIA induced fibrosis of the IFP body.


Asunto(s)
Sinovitis , Animales , Cartílago Articular , Inyecciones Intraarticulares , Ácido Yodoacético , Masculino , Ratas , Ratas Wistar
5.
Mol Psychiatry ; 20(1): 109-17, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25349165

RESUMEN

Certain mutant Alzheimer's amyloid-ß (Aß) peptides (that is, Dutch mutant APP(E693Q)) form complexes with gangliosides (GAß). These mutant Aß peptides may also undergo accelerated aggregation and accumulation upon exposure to GM2 and GM3. We hypothesized that increasing ß-hexosaminidase (ß-hex) activity would lead to a reduction in GM2 levels, which in turn, would cause a reduction in Aß aggregation and accumulation. The small molecule OT1001 is a ß-hex-targeted pharmacological chaperone with good bioavailability, blood-brain barrier penetration, high selectivity for ß-hex and low cytotoxicity. Dutch APP(E693Q) transgenic mice accumulate oligomeric Aß as they age, as well as Aß oligomer-dose-dependent anxiety and impaired novel object recognition (NOR). Treatment of Dutch APP(E693Q) mice with OT1001 caused a dose-dependent increase in brain ß-hex levels up to threefold over those observed at baseline. OT1001 treatment was associated with reduced anxiety, improved learning behavior in the NOR task and dramatically reduced GAß accumulation in the subiculum and perirhinal cortex, both of which are brain regions required for normal NOR. Pharmacological chaperones that increase ß-hex activity may be useful in reducing accumulation of certain mutant species of Aß and in preventing the associated behavioral pathology.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Antipsicóticos/uso terapéutico , Trastornos del Conocimiento , Gangliósidos/metabolismo , beta-N-Acetilhexosaminidasas/metabolismo , Enfermedad de Alzheimer/genética , Animales , Barrera Hematotesticular/efectos de los fármacos , Células Cultivadas , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Gangliósidos/uso terapéutico , Humanos , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Mutación/genética , Reconocimiento en Psicología/efectos de los fármacos , Factores de Tiempo
6.
Oncogene ; 34(3): 314-22, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24469041

RESUMEN

Tumor suppressor protein p19(ARF) (Arf; p14(ARF) in humans) functions in both p53-dependent and -independent modes to counteract hyper-proliferative signals caused by proto-oncogene activation, but its p53-independent activities remain poorly understood. Using the tandem affinity purification-tag technique, we purified Arf-containing protein complexes and identified p68 DEAD-box protein (DDX5) as a novel interacting protein of Arf. In this study, we found that DDX5 interacts with c-Myc, and harbors essential roles for c-Myc-mediated transcription and its transforming activity. Furthermore, when c-Myc was forcibly expressed, the expression level of DDX5 protein was drastically increased through the acceleration of protein synthesis of DDX5, suggesting the presence of an oncogenic positive feedback loop including c-Myc and DDX5. Strikingly, Arf blocked the physical interaction between DDX5 and c-Myc, and drove away DDX5 from the promoter of c-Myc target genes. These observations most likely indicate the mechanism by which Arf causes p53-independent tumor-suppressive activity.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , ARN Helicasas DEAD-box/metabolismo , Retroalimentación Fisiológica , Proteínas Proto-Oncogénicas c-myc/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , ARN Helicasas DEAD-box/genética , Embrión de Mamíferos/citología , Fibroblastos/metabolismo , Células HEK293 , Células HeLa , Humanos , Immunoblotting , Células MCF-7 , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Células 3T3 NIH , Unión Proteica , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-myc/genética , Interferencia de ARN
7.
J Viral Hepat ; 20(8): 556-65, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23808994

RESUMEN

Hepatic CD1d-restricted and natural killer T-cell populations are heterogeneous. Classical 'type 1' α-galactosylceramide-reactive CD1d-restricted T cells express 'invariant' TCRα ('iNKT'). iNKT dominating rodent liver are implicated in inflammation, including in hepatitis models. Low levels of iNKT are detected in human liver, decreased in subjects with chronic hepatitis C (CHC). However, high levels of human hepatic CD161(±) CD56(±) noninvariant pro-inflammatory CD1d-restricted 'type 2' T cells have been identified in vitro. Unlike rodents, healthy human hepatocytes only express trace and intracellular CD1d. Total hepatic CD1d appears to be increased in CHC and primary biliary cirrhosis. Direct ex vivo analysis of human intrahepatic lymphocytes (IHL), including matched ex vivo versus in vitro expanded IHL, demonstrated detectable noninvariant CD1d reactivity in substantial proportions of HCV-positive livers and significant fractions of HCV-negative livers. However, α-galactosylceramide-reactive iNKT were detected only relatively rarely. Liver CD1d-restricted IHL produced IFNγ, variable levels of IL-10 and modest levels of Th2 cytokines IL-4 and IL-13 ex vivo. In a novel FACS assay, a major fraction (10-20%) of hepatic T cells rapidly produced IFNγ and up-regulated activation marker CD69 in response to CD1d. As previously only shown with murine iNKT, noninvariant human CD1d-specific responses were also augmented by IL-12. Interestingly, CD1d was found selectively expressed on the surface of hepatocytes in CHC, but not those CHC subjects with history of alcohol usage or resolved CHC. In contrast to hepatic iNKT, noninvariant IFNγ-producing type 2 CD1d-reactive NKT cells are commonly detected in CHC, together with cognate ligand CD1d, implicating them in CHC liver damage.


Asunto(s)
Antígenos CD1d/análisis , Hepatitis C Crónica/inmunología , Hepatocitos/química , Hígado/inmunología , Linfocitos T/inmunología , Adulto , Anciano , Animales , Citocinas/metabolismo , Femenino , Hepatitis C Crónica/patología , Humanos , Hígado/patología , Masculino , Ratones , Persona de Mediana Edad , Linfocitos T/química , Adulto Joven
8.
Adv Exp Med Biol ; 789: 449-454, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23852528

RESUMEN

The aim of this study was to develop a NIRS-based neurofeedback system to modulate activity in the prefrontal cortex (PFC). We evaluated the effectiveness of the system in terms of separability of changes in oxy-Hb and its derivative. Training with neurofeedback resulted in higher separability than training without neurofeedback or no training, suggesting that the neurofeedback system could enhance self-control of PFC activity. Interestingly, the dorsolateral PFC exhibited enhanced activity and high separability after neurofeedback training. These observations suggest that the neurofeedback system might be useful for training subjects to regulate emotions by self-control of dorsolateral PFC activity.


Asunto(s)
Aprendizaje/fisiología , Neurorretroalimentación/fisiología , Corteza Prefrontal/fisiología , Humanos , Oxihemoglobinas/metabolismo , Corteza Prefrontal/metabolismo , Espectroscopía Infrarroja Corta/métodos , Adulto Joven
9.
Diabetes Res Clin Pract ; 85(1): 47-52, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19427051

RESUMEN

The effectiveness of BIAsp 30 step-up therapy in achieving glycemic control in Japanese patients with type 2 diabetes mellitus was investigated. Study subjects were 99 patients with type 2 diabetes mellitus aged over 20 years who were judged to require insulin therapy due to poor glucose control (HbA1c level of > or =7.5%). BIAsp 30 dosage was determined by the patient's attending physician; coadministration of hypotensive agents and antilipemic agents was permitted, but OAD coadministration was limited to patients already receiving such drugs at the start of the study. Patients who did not achieve HbA1c <6.5% after 16+/-5 weeks with QD (Phase 1) were stepped up to BID (Phase 2). If patients still had not achieved HbA1c <6.5% after 16+/-5 weeks with BID, they were stepped up to TID (Phase 3). 55 of the 99 enrolled subjects completed the study and the rates of achievement of HbA1c <6.5% and HbA1c <7.0% were 45.5% and 74.5%, respectively. Of all registered subjects, 5.1% (5/99) achieved HbA1c <6.5% in QD, 19.5% (16/82) in BID, and 20.6% (7/34) in TID. Statistically significant reductions in HbA1c levels were recorded at the conclusion of each phase, with no incidents requiring intervention, indicating that BIAsp 30 step-up therapy is a safe, simple therapy that can be useful in achieving better glycemic control for Japanese patients with type 2 diabetes mellitus.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Insulina/análogos & derivados , Administración Oral , Adulto , Anciano , Insulinas Bifásicas , Dieta para Diabéticos , Esquema de Medicación , Ejercicio Físico , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Insulina Aspart , Insulina Isófana , Japón , Masculino , Persona de Mediana Edad , Seguridad , Adulto Joven
10.
Appl Radiat Isot ; 67(7-8): 1387-91, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19285418

RESUMEN

Economic scale of radioisotopes (RI) in Japan is studied in the field of medicine, agriculture and a part of industry. (1) RI is used during medical examination with economic scale by 1.7M$ (million dollars) in 1997 and 0.4M$ in 2005. (2) Economic scale of RI utilization in agriculture is 4M$ for R&D, 127M$ for environmental protection and 1M$ for chronology. RI usage in agriculture is increased five times due to needs at environmental technology lasted after the Kyoto protocol. (3) Indirect economic scale of RI ((85)Kr, (147)Pm, (90)Cr) usage in paper fabrication field in Japan for 2006 is 8432M$.


Asunto(s)
Medicina Nuclear/economía , Radioisótopos/economía , Agricultura , Industrias , Japón , Papel , Contaminantes Radiactivos/economía
12.
J Oral Rehabil ; 34(11): 827-34, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17919249

RESUMEN

The purpose of this study was to clarify which physiological and anatomical factors were involved in the formation of tongue indentations, which are believed to be a clinical sign of clenching. Twenty-four dentulous subjects were investigated. They were divided into two groups, depending on the presence or absence of tongue indentations: (i) a tongue indentation group and (ii) a no tongue indentation group. Intraoral appliances containing a small pressure sensor were placed at the lingual surfaces of the upper and lower right first molars. Lingual pressure on the lingual surfaces of the upper and lower right first molars was then recorded under different conditions. The tasks selected as physiological factors to be recorded were: (i) silent reading at rest for 10 min, (ii) maximum voluntary clenching (MVC) for 5 s, (iii) 10% of MVC for 1 min and (iv) swallowing. The results for all tasks were compared between groups. Tongue width and dental arch width were also measured as anatomical factors. No significant differences were found between groups during silent reading at rest, clenching, swallowing, or in tongue pressure integration during silent reading at rest. However, a significant difference was found in terms of tongue width (P < 0.05). These results indicate that neither volume of lingual pressure exerted on the lingual surface of the teeth during rest, clenching, nor swallowing are related to the formation of tongue indentations. The results do suggest; however, that tongue width at rest plays an important role in the formation of tongue indentations.


Asunto(s)
Lengua , Adulto , Bruxismo/complicaciones , Deglución , Arco Dental , Femenino , Humanos , Masculino , Presión , Lengua/anatomía & histología , Lengua/fisiología
13.
Oncogene ; 26(41): 6099-105, 2007 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-17384677

RESUMEN

Amplification and overexpression of the miR-17-92 microRNAs (miRNA) cluster at 13q31.3 has recently reported, with pointers to functional involvement in the development of B-cell lymphomas and lung cancers. In the present study, we show that inhibition of miR-17-5p and miR-20a with antisense oligonucleotides (ONs) can induce apoptosis selectively in lung cancer cells overexpressing miR-17-92, suggesting the possibility of 'OncomiR addiction' to expression of these miRNAs in a subset of lung cancers. In marked contrast, antisense ONs against miR-18a and miR-19a did not exhibit such inhibitory effects, whereas inhibition of miR-92-1 resulted in only modest reduction of cell growth, showing significant distinctions among miRNAs of the miR-17-92 cluster in terms of their roles in cancer cell growth. During the course of this study, we also found that enforced expression of a genomic region, termed C2, residing 3' to miR-17-92 in the intron 3 of C13orf25 led to marked growth inhibition in association with double stranded RNA-dependent protein kinase activation. Finally, this study also revealed that the vast majority of C13orf25 transcripts are detected as Drosha-processed cleavage products on Northern blot analysis and that a novel polyadenylation site is present 3' to the miR-17-92 cluster and 5' to the C2 region. Taken together, the present findings contribute towards better understanding of the oncogenic roles of miR-17-92, which might ultimately lead to the future translation into clinical applications.


Asunto(s)
Apoptosis/efectos de los fármacos , Oligonucleótidos Antisentido/farmacología , División Celular/efectos de los fármacos , Línea Celular Tumoral , Cromosomas Humanos Par 13 , Humanos , Etiquetado Corte-Fin in Situ , Neoplasias Pulmonares/patología , MicroARNs/genética , Sistemas de Lectura Abierta , Transcripción Genética
14.
Oncogene ; 26(31): 4600-8, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17260014

RESUMEN

Although widespread metastasis is the major cause of human lung cancer-related deaths, its underlying mechanism remains largely unclear. Our genome-wide comparison of the expression profiles of a highly metastatic lung cancer cell line, NCI-H460-LNM35 (LNM35), and its parental clone, NCI-H460-N15 (N15), resulted in the identification of a cancer metastasis signature composed of 45 genes. Through gene ontology analysis, our study also provided insights into how this 45-gene metastasis signature may contribute to the acquisition of metastatic potential. By applying the signature to datasets of human cancer cases, we could demonstrate significant associations with a subset of cases with poor prognosis not only for the two datasets of cancers of the lung but also for cancers of the breast. Furthermore, we were able to show that enforced expression of the DLX4 homeobox gene, which was identified as a gene with significant downregulation in LNM35 as well as with significant association with favorable prognosis for lung cancer patients, markedly inhibited in vitro motility and invasion as well as in vivo metastasis via both hematogenous and lymphogenous routes. Taken together, these findings indicate that our combined transcriptome analysis is an efficient approach in the search for genes possessing both clinical usefulness in terms of prognostic prediction in human cancer cases and clear functional relevance for studying cancer biology in relation to metastasis.


Asunto(s)
Proteínas de Homeodominio/fisiología , Neoplasias Pulmonares/genética , Metástasis de la Neoplasia/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Factores de Transcripción/fisiología , Animales , Neoplasias de la Mama/genética , Línea Celular Tumoral , Femenino , Perfilación de la Expresión Génica , Humanos , Ratones , Ratones SCID , Pronóstico , Transfección
16.
Oncogene ; 25(2): 271-7, 2006 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-16158054

RESUMEN

The c-jun oncogene is frequently overexpressed in non-small-cell lung cancers (NSCLC), but its functional involvement in lung cancer development has not been clearly elucidated. In this study, we found that among the immediate-early serum responsible genes, exemplified by c-jun, c-fos and c-myc, induction of c-jun in a human bronchial epithelial cell line, BEAS-2B, was dependent on anchorage, in contrast to clear induction of c-fos and c-myc under both anchorage-dependent and -independent conditions. In fact, forced expression of c-jun in BEAS-2B cells significantly increased cell viability and colony formation in soft agar. Furthermore, we also found that such anchorage-dependent regulation of c-jun was lost in a significant fraction of human lung cancer cell lines. Interestingly, suppressed anchorage-independent but not anchorage-dependent growth was noted by constitutive expression of a dominant-negative c-jun mutant in a lung cancer cell line showing dysregulated and sustained c-jun expression in the absence of anchorage. These findings suggest that dysregulated c-jun expression may be involved in the acquisition of anchorage independence in the process of human lung carcinogenesis.


Asunto(s)
Bronquios/metabolismo , Adhesión Celular , Proliferación Celular , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Bronquios/citología , Supervivencia Celular , Ensayo de Unidades Formadoras de Colonias , Ciclina A/metabolismo , Células Epiteliales/citología , Genes Dominantes/fisiología , Genes ras/fisiología , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/genética , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Control Social Formal , Estatmina/metabolismo
17.
J Med Genet ; 42(5): 402-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15863669

RESUMEN

BACKGROUND: Peroxisome proliferator activated receptor-gamma coactivator-1beta (PGC-1beta) is a recently identified homologue of the tissue specific coactivator PGC-1alpha, a coactivator of transcription factors such as the peroxisome proliferators activated receptors and nuclear respiratory factors. PGC-1alpha is involved in adipogenesis, mitochondrial biogenesis, fatty acid beta oxidation, and hepatic gluconeogenesis. METHODS: We studied variation in the coding region of human PPARGC1B in Danish whites and related these variations to the prevalence of obesity and type 2 diabetes in population based samples. RESULTS: Twenty nucleotide variants were identified. In a study of 525 glucose tolerant subjects, the Ala203Pro and Val279Ile variants were in almost complete linkage disequilibrium (R2 = 0.958). In a case-control study of obesity involving a total of 7790 subjects, the 203Pro allele was significantly less frequent among obese participants (p = 0.004; minor allele frequencies: normal weight subjects 8.1% (95% confidence interval: 7.5 to 8.8), overweight subjects 7.6% (7.0 to 8.3), obese subjects 6.5% (5.6 to 7.3)). In a case-control study involving 1433 patients with type 2 diabetes and 4935 glucose tolerant control subjects, none of the examined variants were associated with type 2 diabetes. CONCLUSIONS: Variation of PGC-1beta may contribute to the pathogenesis of obesity, with a widespread Ala203 allele being a risk factor for the development of this common disorder.


Asunto(s)
Proteínas Portadoras/genética , Variación Genética , Obesidad/genética , Anciano , Análisis Mutacional de ADN , Dinamarca/etnología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Frecuencia de los Genes , Pruebas Genéticas , Genotipo , Glucosa/metabolismo , Humanos , Desequilibrio de Ligamiento , Persona de Mediana Edad , Mutación , Obesidad/epidemiología , Proteínas de Unión al ARN
18.
J Neurol Sci ; 229-230: 225-32, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15760644

RESUMEN

Apolipoprotein E (apoE) 4 and aging are risk factors for Alzheimer's disease (AD). Mice expressing human apoE4 and aged wild-type mice show a similarity in the transbilayer distribution of cholesterol in synaptic plasma membranes (SPMs) but differ markedly compared with apoE3 mice and young mice. The largest changes in cholesterol distribution were observed in the SPM exofacial leaflet where there was a doubling of cholesterol. Lipid rafts are thought to be associated with the exofacial leaflet, and we proposed that lipid raft protein and lipid composition would be associated with apoE genotype and age. Lipid rafts were isolated from synaptosomes of different age groups (2, 12, 24 months) of mice expressing human apoE3 and apoE4. Lipid raft markers, alkaline phosphatase (ALP), flotillin-1, cholesterol and sphingomyelin (SM) were examined. Lipid rafts of young apoE4 mice were more similar to older mice as compared with young apoE3 mice in reductions in alkaline phosphatase activity and flotillin-1 abundance. Lipid raft cholesterol and sphingomyelin levels were not significantly different between the young apoE3 and apoE4 mice but cholesterol levels of lipid rafts did increase with age in both genotypes. Results of the present study demonstrate that the two risk factors for Alzheimer's disease, apoE4 genotype and increasing age have similar effects on brain lipid raft protein markers and these findings support the notion that the transbilayer distribution of cholesterol is associated with lipid raft function.


Asunto(s)
Envejecimiento/metabolismo , Apolipoproteínas E/metabolismo , Microdominios de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Sinaptosomas/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Apolipoproteína E3 , Apolipoproteína E4 , Colesterol/sangre , Glicosilfosfatidilinositoles/metabolismo , Humanos , Técnicas In Vitro , Luz , Ratones , Ratones Transgénicos , Dispersión de Radiación , Esfingomielinas/sangre
19.
Neuropathol Appl Neurobiol ; 31(2): 170-80, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15771710

RESUMEN

To confirm the intracellular accumulation of amyloid beta-protein (Abeta), we carefully performed immunohistochemistry using brains of cynomolgus monkeys of various ages. Cortical neurones and their large neurites were immunostained with antibodies against Abeta in young monkey brains. In aged monkey brains, intracellular Abeta localized within cortical neurones; no clear association was found between the presence of intracellular Abeta and senile plaques (SPs). Interestingly, we did not observe Abeta-immunoreactive cortical neurones in brains fixed with neutral buffered formalin. Western blot analyses of microsomal and nerve ending fractions derived from the brains of young to aged monkeys revealed that intracellular Abeta generation changed with age. In the microsomal fraction, the amount of Abeta42 significantly increased in brains from older monkeys (>30 years of age), and the amount of Abeta43 significantly decreased with age in the microsomal fraction. The amount of Abeta40 remained the same regardless of age. Biochemical analyses also showed that intracellular levels of each of these Abeta molecules significantly increased with age in nerve ending fractions. As we previously observed that a similar accumulation of presenilin1, beta-amyloid precursor protein (APP) and APP C-terminal fragment cleaved by beta-secretase in the nerve ending fractions obtained from brains with SPs, the accumulation of intracellular Abeta in this fraction may be closely related to formation of spontaneous SPs with age. Taken together, these results suggest that intensive investigation of age-related changes in the nerve ending will contribute to a better understanding of the pathogenesis of age-related neurodegenerative disorders such as sporadic Alzheimer's disease.


Asunto(s)
Envejecimiento , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Animales , Western Blotting , Encéfalo/patología , Femenino , Inmunohistoquímica , Líquido Intracelular/metabolismo , Macaca fascicularis , Masculino , Terminaciones Nerviosas/metabolismo , Terminaciones Nerviosas/patología , Neuronas/metabolismo , Neuronas/patología , Placa Amiloide/metabolismo , Placa Amiloide/patología
20.
Pharmacopsychiatry ; 36 Suppl 2: S127-9, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14574626

RESUMEN

Regarding deposition of amyloid beta-protein (Abeta) in brains with Alzheimer's disease (AD), we previously identified a novel Abeta species that strongly binds to GM1 ganglioside (GM1) in human brains that exhibit early pathological changes of AD. We hypothesized that Abeta undergoes conformational alteration through its binding to GM1 and acts as a seed. We recently found that an increase in the cholesterol concentration in host membranes markedly accelerates Abeta binding to GM1. We then investigated whether the cholesterol concentration in neuronal membranes could be altered under biological conditions that are associated with risk factors for AD development. We attempted to determine the distribution of cholesterol in the synaptic plasma membranes (SPMs) of human apolipoprotein E (apoE)-knock-in mice and found that the cholesterol concentration in the exofacial leaflet of SPMs of the human apoE4-knock-in mice was approximately twice that of human apoE3-knock-in mice. The results of our studies suggest that an increase in the cholesterol concentration in the neuronal membranes accelerates Abeta aggregation through the formation of an endogenous seed.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Membrana Celular/metabolismo , Colesterol/metabolismo , Gangliosidosis GM1/metabolismo , Membranas Sinápticas/metabolismo , Envejecimiento , Animales , Apolipoproteínas E/genética , Humanos , Liposomas , Ratones , Ratones Transgénicos , Modelos Biológicos , Placa Amiloide , Unión Proteica , Isoformas de Proteínas
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