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1.
Rev. bras. enferm ; 67(5): 810-817, Sep-Oct/2014.
Article in Portuguese | LILACS, BDENF | ID: lil-731211

ABSTRACT

Estudo qualitativo e descritivo, cujo objetivo foi identificar e analisar as representações sociais de educação em saúde à pessoa vivendo com HIV entre profissionais de saúde. Os cenários foram três serviços de atenção à DST/HIV/AIDS, em Belém-PA, Brasil, e 37 profissionais de saúde participaram da pesquisa. A coleta de dados deu-se em 2012-2013 por meio de entrevista em profundidade; a análise utilizou o software Alceste 4.10. Com base no conjunto dos resultados foi possível vislumbrar que a educação em saúde pode ser compreendida a partir de categorias: a configuração do agir educativo; as condições sine qua non: educação no trabalho e estrutura da unidade; o processo pedagógico. Conclui-se que as representações sociais configuram-se como orientação-informação para precaução-prevenção e revelam-se no movimento do agir persistente ao emergente, o que suscita uma educação em saúde permanente para se chegar à integralidade nos serviços.


This is a qualitative and descriptive study, which aimed at identifying and analyzing social representations of health education to HIV patients among health professionals. The setting included three healthcare DST/HIV/AIDS services in Belém-PA, Brazil, and 37 health professionals participated in the study. Data collection was conducted in 2012-2013 on the basis of in-depth interviews and analysis was made on Alceste 4.0 software. Final results indicated that health education can be comprehended in light of categories: educational action; sine qua non: education and training at work, and unit structure; teaching-learning process. Conclusions show that social representations are set as guidance-information for precaution-prevention and that they come forth along continuous and emerging action flow, bringing about permanent health education to ensure healthcare services in full.


Estudio cualitativo y descriptivo, que objetivó identificar y analizar las representaciones sociales de educación en salud a la persona viviendo con HIV entre profesionales de salud. Los escenarios fueron tres servicios de atendimiento al DST/HIV/ SIDA, en Belém-PA, Brasil, y 37 profesionales de salud participaran del estudio. La colecta de datos se dio en 2012-2013, por medio de entrevista en profundidad y el análisis utilizo el software Alceste 4.10. Con base en el conjunto de los resultados fue posible vislumbrar que la educación en salud puede ser comprendida a partir de categorías: la configuración del acto educativo; las condiciones sine qua non: educación en el trabajo y estructura de la unidad; el proceso pedagógico. Se concluye que las representaciones sociales se configuran como orientación-información para precaución-prevención y se revelan en el movimiento del acto persistente al emergente, lo que suscita una educación en salud permanente para llegarse a la integralidad en los servicios.


Subject(s)
Humans , Animals , Male , Female , Rabbits , Antioxidants/administration & dosage , Arteriosclerosis/drug therapy , Probucol/administration & dosage , Ubiquinone/administration & dosage , Ubiquinone/analogs & derivatives , alpha-Tocopherol/administration & dosage , Antioxidants/pharmacokinetics , Aorta/metabolism , Aorta/pathology , Arteriosclerosis/metabolism , Arteriosclerosis/pathology , Coenzymes , Disease Models, Animal , Lipids/blood , Lipoproteins, LDL/metabolism , Probucol/pharmacokinetics , Ubiquinone/metabolism , Ubiquinone/pharmacokinetics , Vitamin E/metabolism , alpha-Tocopherol/pharmacokinetics
2.
Braz. j. med. biol. res ; 47(2): 119-127, 2/2014. graf
Article in English | LILACS | ID: lil-699771

ABSTRACT

Vascular calcification decreases compliance and increases morbidity. Mechanisms of this process are unclear. The role of oxidative stress and effects of antioxidants have been poorly explored. We investigated effects of the antioxidants lipoic acid (LA) and tempol in a model of atherosclerosis associated with elastocalcinosis. Male New Zealand white rabbits (2.5-3.0 kg) were fed regular chow (controls) or a 0.5% cholesterol (chol) diet+104 IU/day vitamin D2 (vitD) for 12 weeks, and assigned to treatment with water (vehicle, n=20), 0.12 mmol·kg-1·day-1 LA (n=11) or 0.1 mmol·kg-1·day-1 tempol (n=15). Chol+vitD-fed rabbits developed atherosclerotic plaques associated with expansive remodeling, elastic fiber disruption, medial calcification, and increased aortic stiffness. Histologically, LA prevented medial calcification by ∼60% and aortic stiffening by ∼60%. LA also preserved responsiveness to constrictor agents, while intima-media thickening was increased. In contrast to LA, tempol was associated with increased plaque collagen content, medial calcification and aortic stiffness, and produced differential changes in vasoactive responses in the chol+vitD group. Both LA and tempol prevented superoxide signals with chol+vitD. However, only LA prevented hydrogen peroxide-related signals with chol+vitD, while tempol enhanced them. These data suggest that LA, opposite to tempol, can minimize calcification and compliance loss in elastocalcionosis by inhibition of hydrogen peroxide generation.


Subject(s)
Animals , Male , Rabbits , Arteriosclerosis/prevention & control , Cyclic N-Oxides/administration & dosage , Thioctic Acid/administration & dosage , Vascular Calcification/prevention & control , Aorta, Thoracic , Arteriosclerosis/chemically induced , Arteriosclerosis/metabolism , Compliance/drug effects , Compliance/physiology , Disease Models, Animal , Spin Labels , Vascular Resistance , Vascular Calcification/chemically induced , Vasoconstriction/drug effects , Vasoconstriction/physiology
3.
Braz. j. med. biol. res ; 45(11): 1086-1094, Nov. 2012. ilus, tab
Article in English | LILACS | ID: lil-650571

ABSTRACT

We identified different lipemic and metabolic responses after the ingestion of a standardized meal by healthy adults and related them to atherosclerotic markers. Samples from 60 normolipidemic adults were collected before and after a liquid meal (40 g fat/m² body surface) at 0, 2, 4, 6, and 8 h for measurements of lipids, free fatty acids (FFA), insulin, cholesteryl ester transfer protein (CETP), autoantibodies to epitopes of oxidized LDL (oxLDL Ab), lipolytic activities, and apolipoprotein E polymorphism. Mean carotid intima-media thickness (cIMT) was determined by Doppler ultrasound. The volunteers were classified into early (N = 39) and late (N = 31) triacylglycerol (TAG) responders to the test meal. Late responders showed lower HDL cholesterol concentration at fasting and in the TAG peak, lower insulin and higher FFA concentrations compared to early responders. Multivariate regression analyses showed that mean cIMT was associated with gender (male) and age in early responders and by cholesterol levels at the 6th hour in late responders. oxLDL Ab were explained by lipoprotein lipase and negatively by hepatic lipase and oxLDL Ab (fasting period) by CETP (negative) and FFA (positive). This study is the first to identify a postalimentary insulin resistance state, combined with a reduced CETP response exclusively among late responders, and the identification of the regulators of postalimentary atherogenicity. Further research is required to determine the metabolic mechanisms described in the different postalimentary phenotypes observed in this study, as well as in different pathological states, as currently investigated in our laboratory.


Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Arteriosclerosis/etiology , Dietary Fats/administration & dosage , Arteriosclerosis/blood , Arteriosclerosis/metabolism , Body Mass Index , Biomarkers/blood , Carotid Intima-Media Thickness , Dietary Fats/metabolism , Hyperlipidemias
4.
Article in English | IMSEAR | ID: sea-139249

ABSTRACT

Background. We used recombinant adeno-associated virus vector of adiponectin (AAV2/1-Acrp30) to study the effects of increased levels of adioponectin (by the administration of rAAV2/1-Acrp30) on arteriosclerosis, glucose and lipid metabolism in Goto–Kakizaki (GK) rats with arteriosclerosis. Methods. Thirty GK rats with arteriosclerosis were divided into 3 equal groups: control group 1, control group 2 and the rAAV2/1-Acrp30-administered group. Saline, virus vector or rAAV2/1-Acrp30 (1012 ng/ml) vector genomes administered to the rats in the corresponding group by intramuscular injection to the posterior limb by single administration, respectively. After 8 weeks, fasting blood glucose, 2-hour postprandial blood glucose, glycosylated haemoglobin, serum insulin, serum total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein were measured in each group, and the ultrastructure of the aorta was seen by light and electron microscopy. Results. Compared with control groups 1 and 2, in the rAAV2/1-Acrp30 group, there was a decrease in urine volume, fasting blood glucose, 2-hour postprandial blood glucose, glycosylated haemoglobin, serum total cholesterol, triglycerides and low-density lipoprotein, and an increase in body weight and high-density lipoprotein (p<0.05), while the level of serum insulin was not changed (p>0.05). Ultrastructure studies of the aorta showed that aortosclerosis in the rAAV2/1-Acrp30-administered group was less, and fewer lipid droplet vacuoles were seen in the vascular endothelial cytoplasm. Also various cell organelles and internal elastic lamina were seen, and there was no formation of lipid droplet and foam cells in the cytoplasm of the media of the smooth muscle. Conclusion. Adiponectin could improve blood glucose and lipid parameters and decrease atherosclerosis in the aorta of GK rats.


Subject(s)
Adenoviridae/genetics , Adiponectin/genetics , Animals , Aorta/pathology , Aorta/ultrastructure , Aortic Diseases/metabolism , Aortic Diseases/pathology , Aortic Diseases/therapy , Arteriosclerosis/metabolism , Arteriosclerosis/pathology , Arteriosclerosis/therapy , Blood Glucose/metabolism , Genetic Therapy/methods , Lipid Metabolism/genetics , Male , Rats , Rats, Inbred Strains , Recombinant Proteins/genetics
5.
Rev. GASTROHNUP ; 12(2): 81-83, mayo-ago.2010.
Article in Spanish | LILACS | ID: lil-645124

ABSTRACT

La arterioesclerosis, es un proceso complejo y multifactorial que se inicia con la identificación de la estría lipídica a los 3 años de edad, lesión que progresa a placa fibrosa y lesión complicada en los años posteriores. La obesidad, es definida como una deposición excesiva de grasa en el cuerpo, que está asociado con consecuencias adversas para parámetros metabólicos, también consecuencias a corto y largo plazo y usualmente también con problemas psicosociales significativos y el desarrollo de enfermedades crónicas. Las dislipemias son uno conjunto de entidades que afectan al metabolismo lipídico y cuyos efectos nocivos son determinantes en el desarrollo del proceso de arteriosclerosis.


Atherosclerosis is a multifactorial complex process that begins with the identification of lipid streak at 3 years of age, injury progressing to fibrous plaque and complicated lesión in subsequent years. Obesity is defined as an excessive deposition of fat in the body, wich is associated with adverse metabolic parameters, also the short-and long-term and usually also with significant psychosocial problems and chronic disease development. The dyslipidemias are one set of entities that affect lipid metabolism and the harmful effects are crucial in the development of aterosclerosis process.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Arteriosclerosis/classification , Arteriosclerosis/diagnosis , Arteriosclerosis/metabolism , Obesity/classification , Obesity/diagnosis , Obesity/metabolism , Dyslipidemias/classification , Dyslipidemias/diagnosis , Dyslipidemias/metabolism , Lipid Metabolism
7.
Braz. j. med. biol. res ; 38(5): 705-711, May 2005. tab, graf
Article in English | LILACS | ID: lil-400951

ABSTRACT

We determined the effect of conjugated equine estrogen plus medroxyprogesterone acetate on calcium content of aortic atherosclerotic lesions in oophorectomized adult New Zealand rabbits submitted to a cholesterol rich diet. Five groups of 10 animals each were studied: G1 = control, G2 = cholesterol diet only, G3 = diet plus conjugated equine estrogen (0.625 mg/day); G4 and G5 = diet, conjugated equine estrogen (0.625 mg/day) plus medroxyprogesterone acetate (5 and 10 mg/day, respectively). Mean weight varied from 2.7 ± 0.27 to 3.1 ± 0.20 kg (P = 0.38) between groups at the beginning and 3.1 ± 0.27 to 3.5 ± 0.20 kg (P = 0.35) at the end of the experiment. Cholesterol and triglyceride levels were determined at the time of oophorectomy, 21 days after surgery (time 0), and at the end of follow-up of 90 days. The planimetric method was used to measure plaque and caryometric method for histopathologic examination of the aorta. Calcium content was determined by the method of von Kossa. A similar increase in cholesterol occurred in all treated groups without differences between them at the end of the study. Groups G4 and G5 had smaller areas of atherosclerotic lesions (2.33 ± 2.8 and 2.45 ± 2.1 cm², respectively) than the groups receiving no progestogens (G2: 5.6 ± 4 and G3: 4.6 ± 2.8 cm²; P = 0.02). The relation between lesion area and total aorta area was smaller in groups treated with combined drugs compared to the groups receiving no progesterone (G4: 14.9 ± 13 and G5: 14.2 ± 13.4 vs G2: 35.8 ± 26 and G3: 25 ± 8 cm², respectively; P = 0.017). Oral conjugated equine estrogen (0.625 mg/day) plus medroxyprogesterone acetate (5 or 10 mg/day) provoked a greater reduction in atherosclerotic plaque area and calcium content in treated groups, suggesting a dose-dependent effect.


Subject(s)
Rabbits , Animals , Female , Aorta/chemistry , Arteriosclerosis/metabolism , Calcium/analysis , Diet, Atherogenic , Estrogens, Conjugated (USP)/pharmacology , /pharmacology , Aorta/drug effects , Calcium/metabolism , Dose-Response Relationship, Drug , Ovariectomy , Time Factors
8.
Arq. bras. cardiol ; 84(4): 314-319, abr. 2005. ilus, graf
Article in Portuguese | LILACS | ID: lil-400308

ABSTRACT

OBJETIVO: Comparar os efeitos da atorvastatina, fluvastatina, pravastatina e simvastatina sobre a função endotelial, a aterosclerose aórtica e o teor de malonodialdeído (MDA) nas LDL nativas, oxidadas e na parede arterial de coelhos hipercolesterolêmicos, depois que as doses destas estatinas foram ajustadas para reduzir o colesterol total plasmático a valores similares. MÉTODOS: Coelhos machos, foram separados em grupos de 10 animais (n=10), chamados hipercolesterolêmico (controle), atorvastatina, fluvastatina, pravastatina e normal. A exceção do grupo normal, os animais foram alimentados com ração padrão acrescida de colesterol a 0,5 por cento e óleo de coco a 2 por cento durante 45 dias. As drogas foram administradas a partir do 15° dia do início do experimento e no 30° dia, as doses foram ajustadas, através do controle do colesterol plasmático, para obter valores semelhantes em cada grupo. Ao final do experimento foi dosado o colesterol plasmático e as lipoproteinas e retirado um segmento de aorta torácica para estudo da função endotelial, da peroxidação lipídica e exame histológico para medida da aterosclerose aórtica. RESULTADOS: As estatinas reduziram significantemente o colesterol total plasmático, as LDL-colesterol e a aterosclerose aórtica. O teor de MDA também foi significantemente reduzido nas LDL nativas e oxidadas, assim como na parede arterial. O relaxamento-dependente do endotélio foi significantemente maior no grupo tratado em comparação ao hipercolesterolêmico. CONCLUSÃO: As estatinas, em doses ajustadas, tiveram efeito significante e similar em reduzir a peroxidação lipídica nas LDL e na parede arterial, na regressão da aterosclerose aórtica e na reversão da disfunção endotelial.


Subject(s)
Animals , Male , Rabbits , Anticholesteremic Agents/pharmacology , Aortic Diseases/drug therapy , Arteriosclerosis/drug therapy , Endothelium, Vascular/drug effects , Hypercholesterolemia/drug therapy , Lipid Peroxidation/drug effects , Aortic Diseases/metabolism , Aortic Diseases/physiopathology , Arteriosclerosis/metabolism , Arteriosclerosis/physiopathology , Cholesterol, LDL/blood , Cholesterol, LDL/drug effects , Cholesterol/blood , Endothelium, Vascular/metabolism , Endothelium, Vascular/physiopathology , Fatty Acids, Monounsaturated/pharmacology , Heptanoic Acids/pharmacology , Hypercholesterolemia/metabolism , Hypercholesterolemia/physiopathology , Indoles/pharmacology , Malondialdehyde/analysis , Pravastatin/pharmacology , Pyrroles/pharmacology , Simvastatin/pharmacology
9.
Mem. Inst. Oswaldo Cruz ; 100(supl.1): 15-18, Mar. 2005.
Article in English | LILACS | ID: lil-402170

ABSTRACT

Endothelial nitric oxide synthase (eNOS) is the primary physiological source of nitric oxide (NO) that regulates cardiovascular homeostasis. Historically eNOS has been thought to be a constitutively expressed enzyme regulated by calcium and calmodulin. However, in the last five years it is clear that eNOS activity and NO release can be regulated by post-translational control mechanisms (fatty acid modification and phosphorylation) and protein-protein interactions (with caveolin-1 and heat shock protein 90) that direct impinge upon the duration and magnitude of NO release. This review will summarize this information and apply the post-translational control mechanisms to disease states.


Subject(s)
Animals , Humans , Arteriosclerosis/metabolism , Diabetes Mellitus/metabolism , Endothelium, Vascular/metabolism , Liver Cirrhosis/metabolism , Nitric Oxide Synthase Type III/metabolism , Nitric Oxide/metabolism , Caveolin 1/physiology , Enzyme Activation , HSP90 Heat-Shock Proteins/physiology
11.
Arch. cardiol. Méx ; 74(1): 53-67, mar. 2004. ilus
Article in Spanish | LILACS | ID: lil-631855

ABSTRACT

Las lipoproteínas de alta densidad (HDL) son una familia de partículas que difieren en tamaño, densidad y composición química. La heterogeneidad de las HDL resulta de la velocidad de síntesis y de catabolismo de las partículas, y de la acción de enzimas y proteínas de transporte que las remodelan continuamente. Los bajos niveles de colesterol HDL correlacionan con un riesgo elevado de desarrollar enfermedad aterosclerosa coronaria. La disminución de las HDL afecta el transporte reverso de colesterol, que es la vía metabólica responsable de la remoción del colesterol excedente de la células periféricas y su transporte hacia el hígado para reciclarlo o eliminarlo. Las HDL poseen además propiedades antiinflamatorias, antioxidativas, antiagregatorias, anticoagulantes y profibrinolíticas in vitro . Algunas de estas propiedades potencialmente antiaterosclerosas, también se han puesto de manifiesto in vivo con infusiones de HDL. Estas evidencias, además de la protección que se logra en modelos animales genéticamente modificados, permite plantear a las HDL como un objetivo primario en la prevención de la aterosclerosis coronaria. Algunos estudios epidemiológicos han demostrado una reducción importante en el riesgo cardiovascular asociado a elevaciones del colesterol HDL, principalmente en prevención secundaria. En consecuencia, elevar las concentraciones de las HDL a través de medidas higiénicas como el ejercicio aeróbico, la pérdida de peso y eliminar el tabaquismo, es ampliamente recomendado para reducir el riesgo coronario. Cuando las medidas higiénicas fallan, la intervención farmacológica con niacina o fibratos debe ser considerada en ciertos pacientes con niveles bajos de HDL. Por último, las diferentes subclases de HDL no poseen las mismas propiedades antiaterogénicas, lo que sugiere que las intervenciones tanto higiénicas como farmacológicas se deberán enfocar en el futuro hacia incrementos de la funcionalidad de las HDL, más que a incremento en la concentración del colesterol HDL.


High density lipoproteins (HDL) are a family of heterogeneous particles that vary in size, density and chemical composition, as a result of their synthesis and catabolism rates, and a continuous intravascular remodeling by the action of enzymes and transport proteins. Low plasma levels of HDL correlate with a high risk of atherosclerotic heart disease. Such a diminished concentration of HDL affect reverse cholesterol transport, which is the metabolic pathway responsible for the movement of cholesterol excess from peripheral tissues to the liver for recycling or excretion. In addition, HDL possess anti-inflammatory, anti-oxidative, anti-aggregatory, anti-coagulant, and pro-fibrinolytic properties, as has been demonstrated by in vitro studies. Some of those potentially anti-atherosclerotic in vitro-properties has been corroborated by HDL infusion in vivo. Such evidences and the protection of susceptible animals from atherosclerosis by transgenic manipulation of HDL metabolism, raise the possibility to focus the HDL plasma levels as a main target in coronary hearth disease prevention. Intervention trials have shown an important reduction in coronary events by rising HDL-cholesterol, mainly in the secondary prevention. Increasing HDL plasma levels by hygienic intervention such as aerobic exercise, weight loss and stop smoking is strongly recommended to reduce coronary risk in primary prevention. Pharmacological intervention to rise the HDL plasma levels with niacin or fibrates, should be considered in some patients as an alternative when hygienic intervention fails. Finally, it most be taken into account that the different HDL subclasses does not possess the same anti-atherosclerotic properties, suggesting that hygienic and pharmacological interventions should focus to increase HDL functionality rather than HDL-cholesterol plasma levels. (Arch Cardiol Mex 2004; 74:53-67).


Subject(s)
Humans , Arteriosclerosis/prevention & control , Cholesterol, HDL/metabolism , Arteriosclerosis/metabolism , Hypolipidemic Agents/therapeutic use
12.
Biocell ; 27(2): 189-196, Aug. 2003.
Article in English | LILACS | ID: lil-384244

ABSTRACT

Remodeling of large and small arteries contributes to the development and complications of hypertension. Artery structural changes in chronic sustained hypertension include vascular smooth muscle cells (VSMC) proliferation and extracellular matrix (ECM) modifications. Extracellular constituents such as proteoglycans (PGs), may modulate vascular stiffness and VSMC growth and differentiation. We examined the effect of growth factors on secreted and membrane-bound PGs synthesis by cultured aortic smooth muscle cells (SMC) from 12- to 14- week-old spontaneously hypertensive rats (SHR) and age-matched Wistar rats. After stimulation with platelet-derived growth factor (PDGF-BB), 10% fetal calf serum (FCS) or 0.1% FCS as control, PGs synthesis (dpm/ng DNA) was evaluated in the medium (M-ECM) and in the cell layer (P-ECM) by a double-isotopic label method using both [3H]-glucosamine and [35S]-sodium sulfate which are incorporated into all complex carbohydrates or only into sulfated dysaccharides, respectively. Data are presented as percent of the control (0.1% FCS). SHR VSMC displayed a significantly greater synthesis of M-ECM [3H]-PGs than Wistar rat cells, with both treatments, but no differences in M-ECM [35S] uptake were found in any case. In the P-ECM, both PDGF-BB and 10% FCS produced a greater effect on [3H]-PGs and sulfated PGs synthesis in VSMC from SHR. An important change seen in SHR cells was a significant decreased sulfation, assessed by [35S]/[3H] ratio, in basal and stimulation conditions. Present results indicate the existence of changes in PGS synthesis and modulation in VSMC from a conduit-artery of SHR and support the pathophysiological role proposed for matrix proteoglycans in the vascular wall changes associated to hypertension and related vascular diseases as atherosclerosis.


Subject(s)
Male , Aorta/metabolism , Hypertension/metabolism , Hypertrophy/metabolism , Extracellular Matrix/metabolism , Muscle, Smooth, Vascular/metabolism , Proteoglycans/metabolism , Aorta/cytology , Arteriosclerosis/metabolism , Arteriosclerosis/pathology , Arteriosclerosis/physiopathology , Cells, Cultured , Cell Division/drug effects , Cell Division/physiology , Platelet-Derived Growth Factor/metabolism , Platelet-Derived Growth Factor/pharmacology , Glucosamine/metabolism , Extracellular Matrix/drug effects , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular , Proteoglycans/drug effects , Proteoglycans , Rats , Rats, Inbred SHR , Sulfur Radioisotopes , Sulfates/metabolism
13.
Experimental & Molecular Medicine ; : 95-102, 2001.
Article in English | WPRIM | ID: wpr-42075

ABSTRACT

Leptin, the product of ob gene, is an endocrine hormone that regulates adipose tissue mass. Recently, leptin has been found to generate a growth signal involving a tyrosine kinase-dependent intracellular pathway and promote angiogenic processes via activation of leptin receptor (Ob-R) in endothelial cells. However, it is not clear how leptin functions to promote multi-step processes involved in the neovascularization at the atherosclerotic plaque. We have examined the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) and Ob-R in human atherosclerotic lesions, leptin-mediated angiogenesis in vivo and in vitro. Immunohistochemical analysis of human atherosclerotic aorta revealed an increased expression of Ob-R in the intima of neorevascularized regions and of both MMPs and TIMPs predominantly in the endothelial lining of intimal neovessels and macrophages/foam cells. In the rat corneal angiogenesis assay, leptin elicited a comparable sensitivity of angiogenic activity to those of vascular endothelial growth factor (VEGF). The immunohistological analysis of the leptin-treated rat cornea showed definitive rises in Ob-R, MMPs and TIMPs expression as well as those of VEGF receptor (VEGFR-1). Leptin (10-40 ng/ml) induced proliferation of the human umbilical vein endothelial cells (HUVECs) and elevation of MMP-2, MMP-9, TIMP-1, and TIMP-2 expression in a dose-dependent manner. Leptin also induced increases of MMP-2, MMP-9, TIMP-1, and Up-regulated the human coronary artery smooth muscle cells (HCASMCs). These findings suggest that leptin, a hormone with pluralistic properties including a mitogenic activity on vascular endothelial cells, plays a role in matrix remodeling by regulating the expression of MMPs and TIMPs. Taken together, our findings further provide evidences for leptin's role as an angiogenesis inducer in the normal organ (rat cornea) and in aberrant vasculature under duress like atherosclerosis.


Subject(s)
Rats , Animals , Arteriosclerosis/metabolism , Blotting, Western , Cell Division , Cells, Cultured , Dose-Response Relationship, Drug , Endothelial Growth Factors/metabolism , Endothelium, Vascular/cytology , Enzyme-Linked Immunosorbent Assay , Fibroblast Growth Factor 2/metabolism , Immunohistochemistry , Leptin/chemistry , Lymphokines/metabolism , Matrix Metalloproteinases/biosynthesis , Neovascularization, Pathologic , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/metabolism , Recombinant Proteins/metabolism , Tissue Inhibitor of Metalloproteinases/metabolism , Umbilical Veins/metabolism , Up-Regulation
14.
Biol. Res ; 33(2): 167-175, 2000. ilus
Article in English | LILACS | ID: lil-443665

ABSTRACT

Atherosclerosis is one of the most common diseases and the principal cause of death in western civilization. The pathogenesis of this disease can be explained on the basis of the 'oxidative-modification hypothesis,' which proposes that low-density lipoprotein (LDL) oxidation represents a key early event. Nitric oxide (*NO) regulates critical lipid membrane and lipoprotein oxidation events by a) contributing to the formation of more potent secondary oxidants from superoxide (i.e.: peroxynitrite), and b) its antioxidant properties through termination reactions with lipid radicals to possibly less reactive secondary nitrogen-containing products (LONO, LOONO). Relative rates of production and steady state concentrations of superoxide and *NO and cellular sites of production will profoundly influence the expression of differential oxidant injury-enhancing and protective effects of *NO. Full understanding of the physiological roles of *NO, coupled with detailed insight into *NO regulation of oxygen radical-dependent reactions, will yield a more rational basis for intervention strategies directed toward oxidant-dependent atherogenic processes.


Subject(s)
Humans , Arteriosclerosis/metabolism , Cholesterol, LDL , Reactive Oxygen Species/metabolism , Oxidative Stress/physiology , Nitric Oxide/physiology , Oxidation-Reduction , Lipid Peroxidation/physiology
15.
Biol. Res ; 33(2): 97-103, 2000.
Article in English | LILACS | ID: lil-443673

ABSTRACT

Scavenger receptors were discovered as cell surface proteins capable of binding and internalization of modified lipoproteins. These receptors exhibit a broad ligand binding specificity including potential physiological and pathophysiological ligands other than modified lipoproteins. Different classes of scavenger receptors have been identified, and their relevance in normal and pathological conditions is under investigation. Recent in vitro and in vivo studies strongly support the role of class A and class B scavenger receptors in lipid transport and atherogenesis.


Subject(s)
Animals , Humans , Arteriosclerosis/metabolism , Lipoproteins, LDL/metabolism , Receptors, Immunologic/metabolism , Biological Transport , Membrane Proteins/metabolism , Receptors, Scavenger , Scavenger Receptors, Class A , Scavenger Receptors, Class B
16.
Biol. Res ; 33(2): 89-96, 2000. ilus, graf
Article in English | LILACS | ID: lil-443674

ABSTRACT

Endothelial dysfunction (ED) is an early event in atherosclerotic disease, preceding clinical manifestations and complications. Increased reactive oxygen species (ROS) have been implicated as important mechanisms that contribute to ED, and ROS's may function as intracellular messengers that modulate signaling pathways. Several intracellular signal events stimulated by ROS have been defined, including the identification of two members of the mitogen activated protein kinase family (ERK1/2 and big MAP kinase, BMK1), tyrosine kinases (Src and Syk) and different isoenzymes of PKC as redox-sensitive kinases. ROS regulation of signal transduction components include the modification in the activity of transcriptional factors such as NFkB and others that result in changes in gene expression and modifications in cellular responses. In order to understand the intracellular mechanisms induced by ROS in endothelial cells (EC), we are studying the response of human umbilical cord vein endothelial cells to increased ROS generation by different pro-atherogenic stimuli. Our results show that Homocysteine (Hcy) and oxidized LDL (oxLDL) enhance the activity and expression of oxidative stress markers, such as NFkB and heme oxygenase 1. These results suggest that these pro-atherogenic stimuli increase oxidative stress in EC, and thus explain the loss of endothelial function associated with the atherogenic process.


Subject(s)
Humans , Arteriosclerosis/metabolism , Endothelial Cells/physiology , Reactive Oxygen Species/metabolism , Oxidative Stress , Signal Transduction/physiology , Arteriosclerosis/genetics , Endothelial Cells/metabolism , Gene Expression , Hyperhomocysteinemia , Homocysteine/metabolism , Lipoproteins, LDL/metabolism , Mitogen-Activated Protein Kinases/metabolism , Signal Transduction/genetics , Umbilical Veins/cytology , Umbilical Veins/metabolism
17.
Yonsei Medical Journal ; : 319-327, 2000.
Article in English | WPRIM | ID: wpr-99748

ABSTRACT

Chronic infection and inflammation have recently been implicated as important etiologic agents for atherosclerosis in general and, in particular, ischemic heart disease. Several agents have been suggested as possible candidates for the chronic inflammation including cytomegalovirus, Helicobacter pylori and Chlamydia pneumoniae. We hypothesized that a vascular infection with C. pneumoniae may induce a chronic inflammatory reaction in the host vascular tissue and activated inflammatory cells may express inflammatory mediators such as cyclooxygenase-2 (COX-2) and matrix metalloproteinases (MMPs). At first, we evaluated the relationship between C. pneumoniae infection and atherosclerosis indirectly by serologic study, and then, to confirm our hypothesis, we performed an immunohistochemical study of atherosclerotic plaques. The seropositive rate of anti-Chlamydia pneumoniae IgG was higher in the disease group (Group I, 59.8%, n = 254) than in the negative control group (Group III, 47.4%, n = 97) (p = 0.041), but the anti-Chlamydia pneumoniae IgA was not different in seropositivity between the two groups (Group I, 64.6%; Group III, 57.7%). The simultaneous seropositive rates of both IgG and IgA were 56.7% in Group I and 43.3% in Group III (p = 0.033). In subgroups without the conventional risk factors of atherosclerosis, these findings were more prominent. Furthermore, we performed immunohistochemical staining on the atherosclerotic aortic tissues obtained from patients that were seropositive to C. pneumoniae (n = 5), by using antibodies to C. pneumoniae, COX-2, and MMP-9. The immunoreactivity for COX-2 and MMP-9 increased in the atherosclerotic plaques itself, predominantly in the surrounding area of immunoreactive C. pneumoniae. These findings support our hypothesis and C. pneumoniae may participate in a pathogenetic mechanism for atherogenesis or progression of atherosclerosis. The present study may open a promising perspective concerning future therapeutic trials of chronic inflammation related atherogenesis under pathophysiological conditions.


Subject(s)
Aged , Female , Humans , Male , Arteriosclerosis/pathology , Arteriosclerosis/microbiology , Arteriosclerosis/metabolism , Chlamydia Infections/complications , Chlamydophila pneumoniae , Matrix Metalloproteinase 9/metabolism , Isoenzymes/metabolism , Middle Aged , Prostaglandin-Endoperoxide Synthases/metabolism , Serologic Tests
18.
Yonsei Medical Journal ; : 68-75, 2000.
Article in English | WPRIM | ID: wpr-33455

ABSTRACT

Neovascularization of the adventitial vasa vasorum with extension into the intima of atherosclerotic lesions is frequently observed, but its pathophysiological significance is still subject to debate. Recently, leptin, the product of the Ob gene, was identified. Leptin, via activation of the endothelial receptor (Ob-R), generates a growth signal involving a tyrosine kinase-dependent intracellular pathway and promotes angiogenic processes. We hypothesized that a high concentration of leptin within vasa vasorum and plaque itself, may influence inflammatory and vascular neovascularization coupling with functional upregulation of the vascular endothelial growth factor (VEGF). Microscopic computerized tomography was utilized for the spatial distribution of vasa vasorum and intimal neovascularization from atherosclerotic human coronary arteries. Atherosclerotic coronary arteries showed a dense plexus of microvessels in the adventitia and plaque itself. Microscopic analysis from human atherosclerotic aortas revealed an increase in the intimal thickness with neovascularization. The immunoreactivity for Ob-R, VEGF and matrix metalloproteinase (MMP) increased in atherosclerotic plaque, predominantly in the endothelial lining of the intimal neovessel and macrophages/foam cells. Our observation of a prominent colocalization between Ob-R, VEGF and MMP supports this hypothesis and these factors participate in the neovascularization of atherosclerotic lesions. The present study is the first report on vascular tissue and it opens a promising perspective concerning future investigations of leptin-dependent modulation of atherogenesis and vascular neovascularization under pathophysiolgical conditions.


Subject(s)
Adult , Humans , Arteriosclerosis/physiopathology , Arteriosclerosis/pathology , Arteriosclerosis/metabolism , Blood Vessels/pathology , Blood Vessels/metabolism , Carrier Proteins/physiology , Carrier Proteins/metabolism , Middle Aged , Neovascularization, Pathologic/physiopathology
19.
Reprod. clim ; 12(2): 74-8, abr.-jun. 1997. ilus, graf
Article in Portuguese | LILACS | ID: lil-201463

ABSTRACT

Säo indiscutíveis os benefícios da hormonioterapia de reposiçäo (TRH) em mulheres climatéricas. A abordagem de pacientes diabéticas candidatas a essa modalidade terapêutica reveste-se de importância, pela complexidade deste distúrbio metabólico. Os autores fazem revisäo da literatura e discutem as alteraçöes inerentes ao metabolismo dos carbohidratos, sua relaçäo com os esteróides sexuais e com os esquemas terapéuticos atualmente empregados na terapia de reposiçäo hormonal.


Subject(s)
Humans , Female , Climacteric/metabolism , Diabetes Mellitus , Estrogen Replacement Therapy , Arteriosclerosis/metabolism , Carbohydrates/metabolism , Cardiovascular Diseases , Hyperinsulinism/physiopathology , Risk Factors , Steroids/pharmacology
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