Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Curr Mol Med ; 15(5): 462-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26122656

RESUMO

Tumor-derived autologous antigenic peptides when bound to endogenous 70 kDa family heat shock proteins (HSP70) are able to induce effective T-cell responses against tumors. However, efficacy of HSPbased vaccines in clinical practical stand point still has a number of certain limitations including an activation of immune responses against alien non-human HSPs. In this study we reconstructed the complexes of human recombinant HSPs70 (human recombinant HSP70A1B and HSC70 mixture; hrHSPs70) with antigenic lowweight peptides derived from mice B16F10 melanoma cell lysate (PepMCL) in vitro and investigated the prophylactic potential of these complexes to activate anti-tumor immunity in melanoma mouse model. Our results demonstrate that the developed prophylactic vaccine elicits melanoma-specific immune responses and anti-tumor effects against melanoma. These results suggest that hrHSPs70 has capability to reconstitute complexes with peptides obtained from tumor cells lysates in vitro and, therefore, can be used for delivery of multiple antigenic peptides into antigen-presenting cells (APCs) to activate effectors cells. Designed in such a way hrHSPs70-based prophylactic vaccines induce immune responses resulting in a significant efficient prevention of tumor growth and metastases.


Assuntos
Proteínas de Choque Térmico , Antígenos Específicos de Melanoma , Melanoma/imunologia , Fragmentos de Peptídeos , Proteínas Recombinantes de Fusão/imunologia , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Modelos Animais de Doenças , Feminino , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/isolamento & purificação , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Melanoma/mortalidade , Melanoma/patologia , Melanoma/terapia , Melanoma Experimental , Antígenos Específicos de Melanoma/química , Antígenos Específicos de Melanoma/imunologia , Antígenos Específicos de Melanoma/metabolismo , Camundongos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Proteínas Recombinantes de Fusão/administração & dosagem , Carga Tumoral/imunologia
2.
Curr Med Chem ; 21(19): 2208-17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24372221

RESUMO

Mitochondrial dysfunction plausibly underlies the aging-associated brain degeneration. Mitochondria play a pivotal role in cellular bioenergetics and cell-survival. Oxidative stress consequent to chronic hypoperfusion induces mitochondrial damage, which is implicated as the primary cause of cerebrovascular accidents (CVA) mediated Alzheimer's disease (AD). The mitochondrial function deteriorates with aging, and the mitochondrial damage correlates with increased intracellular production of oxidants and pro-oxidants. The prolonged oxidative stress and the resultant hypoperfusion in the brain tissues stimulate the expression of nitric oxide synthase (NOS) enzymes, which further drives the formation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). The ROS and RNS collectively contributes to the dysfunction of the blood-brain barrier (BBB) and damage to the brain parenchymal cells. Delineating the molecular mechanisms of these processes may provide clues for the novel therapeutic targets for CVA and AD patients.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Doença de Alzheimer/tratamento farmacológico , Animais , Antioxidantes/uso terapêutico , Encéfalo/irrigação sanguínea , Humanos
3.
J Neurol Sci ; 283(1-2): 178-81, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19272617

RESUMO

Brain energy disorders and oxidative stress due to chronic hypoperfusion are considered to be major risk factors in the pathogenesis of dementia. The aim of our study was to evaluate changes of the brain creatine kinase (BB-CK) reaction and mitochondrial respiratory chain function in male Wistar rats exposed to chronic cerebral hypoperfusion. Three-vessel occlusion (3-VO) was accomplished without thoracotomy using a minimally-invasive surgical approach for the occlusion of the brachiocephalic trunk and the left common carotid artery (CCA). The forward rate constant of creatine kinase (k(for)) was measured in vivo by saturation transfer of (31)P magnetic resonance spectroscopy (MRS) at 2 and 10 weeks of permanent 3-VO. The function of the mitochondrial respiratory chain in vitro was assessed polarographically at 10 weeks after 3-VO. When compared to the controls, the significant 42% reduction of k(for) at 2 resp. 10 weeks indicated disorders in brain energy metabolism, which is in agreement with the 12% decrease of the oxidative phosphorylation coefficient (ADP:O) and with the 14% decrease of the oxidative phosphorylation rate (OPR) measured in isolated mitochondria. Oxidative modification of the creatine kinase system (inactivation of enzymes) and metabolic disorders due to chronic 3-VO, thus, may participate in vascular cognitive impairment and neuronal degeneration.


Assuntos
Encéfalo/metabolismo , Doenças das Artérias Carótidas/metabolismo , Demência Vascular/metabolismo , Modelos Animais de Doenças , Procedimentos Neurocirúrgicos/métodos , Ratos , Animais , Creatina Quinase/metabolismo , Transporte de Elétrons/fisiologia , Espectroscopia de Ressonância Magnética , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Mitocôndrias/metabolismo , Oxirredução , Isótopos de Fósforo , Fosforilação , Polarografia , Ratos Wistar , Fatores de Tempo
4.
J Submicrosc Cytol Pathol ; 38(2-3): 85-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17784635

RESUMO

The purpose of this study was to elucidate using transmission electron microscopy (TEM) the ultrastructural changes that occur within the cortical gray matter of a novel reproducible model of congenital hydrocephalus in mice created to overexpress the cytokine transforming growth factor-beta1 (TGF-beta1) in the central nervous system. Brain tissue was obtained from mice from a colony engineered to overexpress TGF-beta1 at two days postpartum and compared to a wild-type aged-matched control. This tissue was fixed using a solution containing 1.25% paraformaldehyde and 1.25% glutaraldehyde in phosphate buffer at least 3-4 h and then cut into 40-50 microm sections. Randomly selected thin sections were stained with uranyl acetate and lead citrate, and then analyzed using a JEOL-100CX or 1200EX transmission electron microscope at accelerating voltage 80 kV. Dramatic neuronal and glial pathology was observed throughout the cortical neuropil in TGF-beta1 mice. The most striking change in the hydrocephalic mice was severe edema with extracellular fluid, possibly due to cerebrospinal fluid (CSF) penetration into the cortex. In addition, severe disruption of the cytoplasmic matrix was seen throughout the cortex, with damage to cellular organelles and particularly severe damage to mitochondria. Our results suggest that congenital hydrocephalus may be associated with significant damage to cortical tissue.


Assuntos
Córtex Cerebral/ultraestrutura , Modelos Animais de Doenças , Hidrocefalia/patologia , Microscopia Eletrônica de Transmissão/métodos , Fator de Crescimento Transformador beta1/metabolismo , Animais , Animais Recém-Nascidos , Edema Encefálico/patologia , Hidrocefalia/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuroglia/ultraestrutura , Neurônios/ultraestrutura , Fator de Crescimento Transformador beta1/genética
5.
Histol Histopathol ; 20(1): 261-73, 2005 01.
Artigo em Inglês | MEDLINE | ID: mdl-15578444

RESUMO

Structural changes in vessels under the influence of ischemia play an important role in the pathogenesis of many diseases, most important of which are stroke and myocardial infarction or myocardial insult. Over the years, information has been gathered, which implicate a role for ischemic vascular changes in the pathogenesis of crush-syndrome, atherosclerosis and other vascular diseases. When blood vessels are damaged they become unresponsive to a stimulus, which normally elicits vasodilatation and can lead to intraluminal thrombosis and ischemic events. The aim of this review is to explore the structural changes seen in vessels affected by ischemia reperfusion injury. With ischemia, the development of observable changes to vascular structure is multifactorial. One key factor is reperfusion ischemic injury. Moreover, the duration of the ischemic event is an important factor when determining both the prognosis and the type of morphological change that is observable in affected vessel walls. In this regard, the deleterious progression of blood flow impairment and its severity depends on the specific organ involved and the type of tissue affected. Further, there are regional differences within affected tissues and the degree of microvascular injury is well correlated with differences in the nature and severity of the ischemic event. Any method aimed at preventing and treating ischemic reperfusion injuries in vessels, based on these investigations, should likewise be able to decrease the early signs of brain, cerebrovascular and heart injury and preserve normal cellular architecture.


Assuntos
Vasos Sanguíneos/lesões , Endotélio Vascular/metabolismo , Isquemia/tratamento farmacológico , Isquemia/metabolismo , Animais , Vasos Sanguíneos/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , Humanos , Microscopia Eletrônica , Ratos , Traumatismo por Reperfusão/tratamento farmacológico
6.
J Neural Transm (Vienna) ; 112(7): 921-32, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15583960

RESUMO

Oxidative damage of biological macromolecules is a hallmark of most neurodegenerative disorders such as Alzheimer, Parkinson and diffuse Lewy body diseases. Another important phenomenon involved in these disorders is the alteration of iron and copper homeostasis. Data from the literature support the involvement of metal homeostasis in mitochondrial dysfunction, protein alterations and nucleic acid damage which are relevant in brain function and consequently, in the development of neurodegenerative disorders. Although alterations in transition metal homeostasis, redox activity, and localization are well documented, it must be determined how alterations of specific copper- and iron-containing metalloenzymes are also involved in Alzheimer disease. The clarification of these phenomena can open a new window for understanding the mechanisms underlying neurodegeneration and, consequently, for the development of new therapeutic strategies such as gene therapy and new pharmaceutical formulations with antioxidant and chelating properties.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/fisiopatologia , Estresse Oxidativo/fisiologia , Animais , Cobre/metabolismo , Humanos , Ferro/metabolismo , Oxirredução
7.
Vestn Khir Im I I Grek ; 163(1): 105-7, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15143600

RESUMO

Total endoprosthesis of the hip joint is an effective method of rehabilitation of patients with a severe pathology of the hip joint. But the lack of exact criteria of assessment of restriction of vital activity of patients after total endoprosthesis results in leveling the effects of medical rehabilitation due to the existing stereotype solution of the MSE bureau and so the majority of patients (90%) after operation get invalidization of the I and II groups for a long time without sufficient causes. Results of complex clinico-rentgenological, biomechanical, electrophysiological examinations and expert assessment of 450 patients after implantation of various domestic and foreign endoprostheses allowed the elaboration of differentiated criteria for the examination of restricted viral activity depending on the nosological form of the disease, degree of the disturbance of the statico-dynamic function, prognosis, complications, character and conditions of work.


Assuntos
Artroplastia de Quadril/métodos , Avaliação da Deficiência , Atividade Motora , Inquéritos e Questionários , Humanos , Reprodutibilidade dos Testes
8.
J Submicrosc Cytol Pathol ; 36(3-4): 225-40, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15906597

RESUMO

Many factors play a role in the development of atherosclerotic lesions. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia (FH). FH is a genetic disease characterized by a deficiency, and/or mutation, of receptors for low density lipoprotein (LDL) on the plasmalemma of endothelial cells (EC), a high level of low density lipoprotein in the plasma, and early, spontaneous development of atherosclerosis and skin xanthoma. In this review we describe Watanabe heritable hyperlipidemic (WHHL) rabbits, which represent such an animal model for human FH. This strain of the rabbits is characterized by a genetic deficiency or mutation of functional LDL receptors and develops severe atherosclerosis, which is pathologically similar to familial homozygous hyperlipidemic patients. The most completely characterized animal model is the Watanabe rabbit, a model of homozygous and heterozygous type IIa hypercholesterolemia related to an LDL receptor deficiency. Additional manipulation such as aortic injury in this rabbit model induces the development of atherosclerotic lesions that are structurally similar to those found in humans. Thus, this model of hypercholesterolemia fulfils the above criteria set, i.e. it is able to provide new insights for a better understanding of the pathogenesis of atherosclerosis and for testing new treatment strategies.


Assuntos
Arteriosclerose/patologia , Hiperlipoproteinemia Tipo II/patologia , Receptores de LDL/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Arteriosclerose/genética , Arteriosclerose/metabolismo , Modelos Animais de Doenças , Humanos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/metabolismo , Coelhos , Receptores de LDL/deficiência , Receptores de LDL/genética
9.
J Submicrosc Cytol Pathol ; 35(3): 253-66, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14690173

RESUMO

X-ray contrast media induce damage to the endothelial layer of vessels and initiate the formation of thrombosis, which is a complication for clinical diagnostic procedures. The future determination of the mechanisms, which underlie the damaging effect of X-ray contrast medium on vascular wall cells, especially vascular endothelium and possible prevention of this damage by vasoprotector, will result in a larger application in diagnostic procedures. The aim of the present study is to analyze the effect of X-ray contrast media (Verographin, Iodamid and Iodolipol) on the arterial endothelium morphology by using ultrastructural techniques (scanning and transmission electron microscopy, SEM and TEM respectively). Experiments have been carried out on New Zealand white rabbits (6 month old) and Wistar rats (6-8 month old) after a single injection of X-ray contrast media with and without prior heparin treatment. Control groups of animals were exposed to the same procedure but without X-ray contrast media injection and only received isotonic saline solution. The following time points were selected: 1, 6, 24, 72 h and 7 days. At the end of the experiments, animals were anesthetized by pentobarbital and then perfused with a balanced buffer for 1 min and followed by perfusion fixation with Karnovsky's fixative containing buffered solution of 2.5% paraformaldehyde and 2.5% glutaraldehyde (pH 7.36) at least 30 min. The aortic tissue was removed and immediately placed into a fresh portion of the same fixative. Aortic samples were then prepared for scanning and transmission electron microscopy (SEM and TEM respectively). Immediately after the injection of X-ray contrast media, the number of microvilli and blebs on the luminal surface of the endothelial cells (EC) significantly increased. Very often, nuclear portions of the EC sharply protruded into the vessel lumen. Clusters of spindle-shaped EC were seen throughout the endothelial monolayer. These changes persist through the 72-h period after X-ray contrast media injection. Moreover, the desquamation and denudation of the EC from the monolayer is often observed and this is accompanied by the presence of a microthrombus on the vessel surface. Seven days after the post-injection period, endothelial monolayers still show severe damage, which often coexists with the presence of a different sized microthrombus on the vessel surface. However, the degree of lesion formation in most areas is substantially decreased as compared to the early period of post-injection (24 and 72 h). Heparin treated group shows intact morphology similar to the control experimental groups (saline injected group). Infrequently, minimal morphological changes of the endothelium, such as increased number of microblebs and microvilli, were seen with heparin treatment. We conclude that the negative side effects of the X-ray contrast media can be eliminated by a single injection of heparin or other vasoprotector prior to the diagnostic procedure.


Assuntos
Aorta Abdominal/efeitos dos fármacos , Doenças da Aorta/prevenção & controle , Meios de Contraste/toxicidade , Endotélio Vascular/efeitos dos fármacos , Heparina/farmacologia , Animais , Aorta Abdominal/ultraestrutura , Doenças da Aorta/induzido quimicamente , Doenças da Aorta/patologia , Antagonismo de Drogas , Endotélio Vascular/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Coelhos , Ratos , Ratos Wistar
10.
J Neural Transm Suppl ; (62): 69-75, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12456052

RESUMO

Over the past decade, oxidative stress has been established as the earliest cytological feature of Alzheimer disease and an attractive therapeutic target. The major challenges now are establishing the source of the reactive oxygen and what oxidative stress tells us about the etiology of Alzheimer disease. These are complex issues since a variety of enzymatic and non-enzymatic processes are involved in reactive oxygen formation and damage to macromolecules. In this review, we consider disease mechanisms that show the greatest promise for future research.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Idoso , Humanos
11.
J Submicrosc Cytol Pathol ; 34(1): 37-50, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11989855

RESUMO

The absence of perivascular nerves in tumour vessels suggests that endothelium derived vasoactive substances [nitric oxide (NO) and endothelin-1 (ET-1)] may be key factors in controlling tumour blood flow during tumour growth and metastasis. We have studied the ultrastructural distribution and immunoreactivity of different NO synthase (NOS) isoforms and ET-1 in human colorectal metastatic liver tumour tissues using pre-embedding peroxidase-anti-peroxidase and post-embedding immunoelectron microscopic triple gold labelling techniques. Dramatically lower NOS 1 immunoreactivity was observed in tumour vascular endothelium (1-3% and 15-20% in tumour and normal groups, respectively). As compared to control groups there were significantly less NOS3 immunopositive EC in metastatic tumour vessels (45-50% and 1-3% in normal and tumour groups, respectively). A striking rise in NOS2 was observed in tumour vessel endothelium (< 1% in normal and 65-70% in tumour vessel endothelium). ET-1 immunoreactivity levels were also significantly higher in tumour vessel endothelium (85-90% in tumour, 15-20% in normal group). This increased expression of NOS2 and ET-1 immunoreactivity was accompanied by the increased expression of three NOS isoforms and ET-1 immunoreactivity in liver parenchymal cells. These data suggest that metastatic tumour vessel endothelium is characterized by increased expression of NOS2 and ET-1 and by decreases in NOS1 and NOS3. These characteristics are associated with the overexpression of all three NOS isoforms and ET-1 immunoreactivity in non-vascular cells.


Assuntos
Neoplasias Colorretais/patologia , Endotelina-1/biossíntese , Endotélio Vascular/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Óxido Nítrico Sintase/biossíntese , Idoso , Endotélio Vascular/ultraestrutura , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/ultraestrutura , Pessoa de Meia-Idade , Óxido Nítrico Sintase/antagonistas & inibidores
12.
J Submicrosc Cytol Pathol ; 33(1-2): 141-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11686395

RESUMO

In the present study we used scanning electron microscopy (SEM) to investigate morphological changes of non-transformed line of human bronchial smooth muscle cells (bSMC) induced by different agonists. Explants of normal bronchi were dissected and subcultured between 2 and 6 passage. In addition, smooth muscle actin content was assessed by SDS-PAGE electrophoresis, and its isoelectric point by IPG followed by immunoblotting. SMC were fixed by 2.0% paraformaldehyde and 2% glutaraldehyde and then were post-fixed by OSO4 and followed by dehydration and gold coating. Cytosolic free calcium was measured using adherent cells incubated with 500 microM Fura-2 acetoxymethylester and monitored by single excitation fluorimetry. Cultured cells possess predominantly charged actin isoforms with pI at 4.95; they respond to acetylcholine (100 microM), bradykinin (5 microM) and sulfidopeptide leukotriens (0.3-1.0 microM) with contraction, marked morphological lesions, such as widespread monolayer disorganization, extension of cell contacts. The number of microvilli on the cell surfaces was correlated with the degree of the alterations of the cellular morphology. Receptor antagonists antagonized these changes: atropine (0.3 microM), HOE 140 (1 microM) and MK 571 (1 microM). Acetylcholine and bradykinin induced a biphasic elevation of cytosolic calcium, which was antagonized by their receptor antagonists. Calcium changes in response to agonists were maintained over repetitive passages. Therefore, morphological changes seen in human bronchial SMC in culture with physiological response to various, structurally unrelated agonists can be future concern for the study the possible testing of the different pharmacological substances.


Assuntos
Bradicinina/análogos & derivados , Brônquios/patologia , Músculo Liso/ultraestrutura , Acetilcolina/farmacologia , Actinas/análise , Actinas/metabolismo , Bradicinina/farmacologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Cálcio/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Fura-2/análogos & derivados , Fura-2/farmacologia , Humanos , Ponto Isoelétrico , Leucotrienos/farmacologia , Microscopia Eletrônica de Varredura , Microvilosidades/efeitos dos fármacos , Microvilosidades/ultraestrutura , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/farmacologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Propionatos/farmacologia , Quinolinas/farmacologia
13.
J Neuropathol Exp Neurol ; 60(8): 759-67, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11487050

RESUMO

Recently, we demonstrated a significant increase of an oxidized nucleoside derived from RNA, 8-hydroxyguanosine (8OHG), and an oxidized amino acid, nitrotyrosine in vulnerable neurons of patients with Alzheimer disease (AD). To determine whether oxidative damage is an early- or end-stage event in the process of neurodegeneration in AD, we investigated the relationship between neuronal 8OHG and nitrotyrosine and histological and clinical variables, i.e. amyloid-beta (A beta) plaques and neurofibrillary tangles (NFT), as well as duration of dementia and apolipoprotein E (ApoE) genotype. Our findings show that oxidative damage is quantitatively greatest early in the disease and reduces with disease progression. Surprisingly, we found that increases in A beta deposition are associated with decreased oxidative damage. These relationships are more significant in ApoE epsilon4 carriers. Moreover, neurons with NFT show a 40%-56% decrease in relative 8OHG levels compared with neurons free of NFT. Our observations indicate that increased oxidative damage is an early event in AD that decreases with disease progression and lesion formation. These findings suggest that AD is associated with compensatory changes that reduce damage from reactive oxygen.


Assuntos
Doença de Alzheimer/metabolismo , Estresse Oxidativo , Tirosina/análogos & derivados , Idoso , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas E/genética , Encéfalo/metabolismo , Encéfalo/patologia , Progressão da Doença , Feminino , Genótipo , Guanosina/análogos & derivados , Guanosina/metabolismo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia , Neurônios/metabolismo , Neurônios/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Tirosina/metabolismo
14.
Exp Mol Pathol ; 71(1): 40-54, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502096

RESUMO

The development and progression of atherosclerotic lesions in Watanabe heritable hyperlipidemic rabbits is associated with increases in inducible nitric oxide synthase (NOS2) and endothelin-1 (ET-1) immunoreactivity. In contrast, there is a reduction of immunoreactivity for neuronal NOS (NOS1) in aortic endothelial cells, but no change in endothelial NOS (NOS3) immunoreactivity. However, subendothelial macrophages and smooth muscle showed a different pattern of immunoreactivity of NADPH-diaphorase (NADPH-d), NOS2, ET-1, and NOS1. The lipid-rich macrophages in the intima were positively labeled for NADPH-d, NOS1, NOS2, NOS3, and ET-1. Smooth muscle cells in the subendothelium and the medial layers of the vascular wall were also positive for these markers. These results are consistent with the reduction of endothelium-dependent vasorelaxation that is known to occur during the development and progression of atherosclerosis in familial hypercholesterolemia. The data suggest a key role for vasoactive substances in the development of atherosclerosis.


Assuntos
Envelhecimento/fisiologia , Aorta Torácica/fisiologia , Arteriosclerose/fisiopatologia , Endotelina-1/fisiologia , Hiperlipidemias/fisiopatologia , Óxido Nítrico Sintase/metabolismo , Túnica Íntima/fisiologia , Animais , Animais Recém-Nascidos , Aorta Torácica/crescimento & desenvolvimento , Aorta Torácica/patologia , Arteriosclerose/genética , Arteriosclerose/patologia , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Di-Hidrolipoamida Desidrogenase/metabolismo , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Endotelina-1/análise , Hiperlipidemias/genética , Hiperlipidemias/patologia , Macrófagos/fisiologia , Masculino , Microscopia Imunoeletrônica , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/ultraestrutura , Desenvolvimento Muscular , Músculo Liso Vascular/crescimento & desenvolvimento , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Coelhos , Túnica Íntima/crescimento & desenvolvimento , Túnica Íntima/patologia
15.
J Neurosci ; 21(9): 3017-23, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11312286

RESUMO

The finding that oxidative damage, including that to nucleic acids, in Alzheimer's disease is primarily limited to the cytoplasm of susceptible neuronal populations suggests that mitochondrial abnormalities might be part of the spectrum of chronic oxidative stress of Alzheimer's disease. In this study, we used in situ hybridization to mitochondrial DNA (mtDNA), immunocytochemistry of cytochrome oxidase, and morphometry of electron micrographs of biopsy specimens to determine whether there are mitochondrial abnormalities in Alzheimer's disease and their relationship to oxidative damage marked by 8-hydroxyguanosine and nitrotyrosine. We found that the same neurons showing increased oxidative damage in Alzheimer's disease have a striking and significant increase in mtDNA and cytochrome oxidase. Surprisingly, much of the mtDNA and cytochrome oxidase is found in the neuronal cytoplasm and in the case of mtDNA, the vacuoles associated with lipofuscin. Morphometric analysis showed that mitochondria are significantly reduced in Alzheimer's disease. The relationship shown here between the site and extent of mitochondrial abnormalities and oxidative damage suggests an intimate and early association between these features in Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Guanosina/análogos & derivados , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Estresse Oxidativo , Tirosina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/etiologia , Cerebelo/patologia , Cerebelo/ultraestrutura , Criança , Pré-Escolar , DNA Mitocondrial/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Lobo Frontal/patologia , Lobo Frontal/ultraestrutura , Guanosina/metabolismo , Hipocampo/patologia , Hipocampo/ultraestrutura , Humanos , Imuno-Histoquímica , Hibridização In Situ , Microscopia Eletrônica , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Neurônios/ultraestrutura , Lobo Temporal/patologia , Lobo Temporal/ultraestrutura , Tirosina/metabolismo
16.
J Neurochem ; 76(2): 435-41, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11208906

RESUMO

Cellular responses to increased oxidative stress appear to be a mechanism that contributes to the varied cytopathology of Alzheimer's disease (AD). In this regard, we suspect that c-Jun N-terminal kinase/Stress activated protein kinase (JNK/SAPK), a major cellular stress response protein induced by oxidative stress, plays an important role in Alzheimer disease in susceptible neurons facing the dilemma of proliferation or death. We found that JNK2/SAPK-alpha and JNK3/SAPK-beta were related to neurofibrillary pathology and JNK1/SAP-Kgamma related to Hirano bodies in cases of AD but were only weakly diffuse in the cytoplasm in all neurons in control cases and in non-involved neurons in diseased brain. In this regard, in hippocampal and cortical regions of individuals with severe AD, the activated phospho-JNK/SAPK was localized exclusively in association with neurofibrillar alterations including neurofibrillary tangles, senile plaque neurites, neuropil threads and granulovacuolar degeneration structures (GVD), completely overlapping with tau-positive neurofibrillary pathology, but was virtually absent in these brain regions in younger and age-matched controls without pathology. However, in control patients with some pathology, as well as in mild AD cases, there was nuclear phospho-JNK/SAPK and translocation of phospho-JNK/SAPK from nuclei to cytoplasm, respectively, indicating that the activation and re-distribution of JNK/SAPK correlates with the progress of the disease. By immunoblot analysis, phospho-JNK/SAPK is significantly increased in AD over control cases. Together, these findings suggest that JNK/SAPK dysregulation, probably resulting from oxidative stress, plays an important role in the increased phosphorylation of cytoskeletal proteins found in AD.


Assuntos
Doença de Alzheimer/enzimologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Especificidade de Anticorpos , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Criança , Ativação Enzimática , Hipocampo/enzimologia , Hipocampo/patologia , Humanos , Immunoblotting , Imuno-Histoquímica , Isoenzimas/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Pessoa de Meia-Idade , Proteína Quinase 10 Ativada por Mitógeno , Proteína Quinase 8 Ativada por Mitógeno , Proteína Quinase 9 Ativada por Mitógeno , Emaranhados Neurofibrilares/enzimologia , Emaranhados Neurofibrilares/patologia , Neurônios/patologia , Estresse Oxidativo , Proteínas Tirosina Quinases/metabolismo , Proteínas tau/biossíntese
17.
Anat Rec ; 260(1): 16-25, 2000 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-10967532

RESUMO

The Donryu rat is resistant to a high cholesterol diet in that typical atheromatous lesions do not develop. Using electron microscopic immunocytochemical techniques, the effects of a CCT diet (4% cholesterol with 1% cholic acid and 0.5% thiouracil) on the distributions of neuronal, macrophage, and endothelial specific nitric oxide synthase (NOS I, NOS II, and NOS III) and endothelin-1 (ET-1) immunoreactivity were examined in the thoracic aortic intima. Atheromatous lesions were absent, but immunocytochemistry showed 1. 4+/-0.52% and 4.0+/-0.9% endothelial cells (EC) with positive staining for NOS I and NOS III, respectively, compared with 16.3+/-2. 5% and 88.6+/-2.48% in control Donryu rats. The CCT-supplemented diet induced expression of NOS II immunoreactivity in thoracic aortic intimal cells. EC, subendothelial macrophages, and smooth muscle cells (SMC) also showed high NOS II-positive staining. The percentage of NOS II-immunoreactive EC was 43+/-1.8%. In control groups, no NOS II immunoreactive cells were observed. The percentage of ET-1 immunopositive cells was also significantly increased by 9. 2+/-0.66% and 64.2+/-1.4% in control and CCT-fed groups, respectively. It is concluded that the administration of a high cholesterol diet in Donryu rats produces endothelial dysfunction associated with changes in the balance of the different isoforms of NOS and ET-1. Therefore, the increase in inducible NOS and ET-1 immunoreactivity seen during the cholesterol-enriched diet appears to be a compensatory reaction of aortic wall cells to the high cholesterol supplementation.


Assuntos
Aorta/metabolismo , Colesterol na Dieta/farmacologia , Endotelina-1/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico Sintase/metabolismo , Animais , Aorta/citologia , Peso Corporal , Ácido Cólico/administração & dosagem , Ácido Cólico/farmacologia , Dieta , Endotélio Vascular/citologia , Imuno-Histoquímica , Lipídeos/sangue , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Ratos , Ratos Endogâmicos , Tiouracila/administração & dosagem , Tiouracila/farmacologia
18.
Int J Dev Neurosci ; 18(4-5): 417-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10817925

RESUMO

Cell bodies of neurons at risk of death in Alzheimer disease have increased lipid peroxidation, nitration, free carbonyls, and nucleic acid oxidation. These oxidative changes are uniform among neurons and are seen whether or not the neurons display neurofibrillary tangles and, in fact, are acutally reduced in the latter case. In consideration of this localization of damage, in this review, we provide a summary of recent work demonstrating some key abnormalities that may initiate and promote neuronal oxidatave damage.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/fisiologia , Humanos
19.
Neuroreport ; 10(15): 3229-32, 1999 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-10574565

RESUMO

Serum amyloid P component (SAP) is associated with amyloid beta (A beta) deposition in Alzheimer disease (AD). Since SAP is exclusively synthesized by peripheral organs, its presence in the brain of AD suggests impairment of the blood-brain barrier (BBB). We studied the association of SAP with A beta deposits in a transgenic mouse model overexpressing beta-protein precursor (betaPP). Both SAP and another extracellular matrix binding protein, basic fibroblastic growth factor bind to the heparinase sensitive sites of A beta deposits in this model. However, no endogenous SAP immunoreactivity was found in the transgenic mouse brain. These results suggest that SAP is not required for A beta deposition, and that this mouse model does not develop the same BBB abnormalities as those seen in AD.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/sangue , Doença de Alzheimer/sangue , Animais , Barreira Hematoencefálica , Artérias Cerebrais/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...