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Id: lil-757366
Autor: Bolsoni-Lopes, Andressa; Alonso-Vale, Maria Isabel C.
Título: Lipolysis and lipases in white adipose tissue – An update
Fonte: Arch. endocrinol. metab. (Online);59(4):335-342, Aug. 2015. ilus.
Idioma: en.
Resumo: Lipolysis is defined as the sequential hydrolysis of triacylglycerol (TAG) stored in cell lipid droplets. For many years, it was believed that hormone-sensitive lipase (HSL) and monoacylglycerol lipase (MGL) were the main enzymes catalyzing lipolysis in the white adipose tissue. Since the discovery of adipose triglyceride lipase (ATGL) in 2004, many studies were performed to investigate and characterize the actions of this lipase, as well as of other proteins and possible regulatory mechanisms involved, which reformulated the concept of lipolysis. Novel findings from these studies include the identification of lipolytic products as signaling molecules regulating important metabolic processes in many non-adipose tissues, unveiling a previously underestimated aspect of lipolysis. Thus, we present here an updated review of concepts and regulation of white adipocyte lipolysis with a special emphasis in its role in metabolism homeostasis and as a source of important signaling molecules.
Descritores: Tecido Adiposo Branco/enzimologia
Lipase/metabolismo
Lipólise/fisiologia
-Tecido Adiposo Branco/fisiologia
Lipase/fisiologia
Limites: Humanos
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME


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Id: lil-706161
Autor: Marques, Simone Cristina; Evangelista, Suzana Reis; Piccoli, Roberta Hilsdorf.
Título: Diversidade e resistência a antibióticos de bactérias psicrotróficas isoladas de tanques coletivos de resfriamento de leite / Diversity of psychotrophic bacteria isolated from the milk cooling collective tanks and antibiotics resistance profile of the microorganisms isolates
Fonte: Rev. Inst. Adolfo Lutz;71(4):670-676, out.-dez. 2012. tab, graf.
Idioma: pt.
Resumo: Bactérias psicrotróficas isoladas da parede, do fundo e da pá de homogeneização de tanques coletivos de resfriamento de leite, após o processo de higienização, foram identificadas e caracterizadas quanto à capacidade de produzir lipase, lecitinas e e protease, bem como determinada a sensibilidade dos isolados a antibióticos. Foram coletadas amostras de 32 tanques coletivos, localizados em diferentes cidades no sul do estado de Minas Gerais, por meio de swab de amostra da superfície, e analisadas pelas técnicas de diluições seriadas com plaqueamento em ágar triptona de soja e incubação das placas a 7 ºC por10 dias. As bactérias isoladas foram identificadas bioquimicamente pelos kits API 20NE (Biomérieux-Brasil) e Bactray I e II (Laborclin-Brasil). Foram identificados 197 isolados, os quais foram caracterizados quanto à produção de lipase, lecitinas e e protease. Para efetuar o teste de resistência a antibióticos, 21 isolados foram selecionados. Contagens entre < 1 e 108 UFC/cm2 foram observadas, com prevalência de Serratia sp., Klebsiela sp. e espécies do gênero Pseudomonas sp. Os isolados identificados apresentaram elevada atividade proteolítica e lipolítica, e a atividade de lecitinas e foi menos pronunciada. A multidroga resistência foi detectada em 54 por cento dos isolados analisados.
Descritores: Antibacterianos
Bactérias/isolamento & purificação
Leite
Lipase
Resistência Microbiana a Medicamentos
Responsável: BR91.2 - Centro de Documentação


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Id: biblio-886808
Autor: SIMÃO, ANDERSON A; MARQUES, TAMARA R; MARCUSSI, SILVANA; CORRÊA, ANGELITA D.
Título: Aqueous extract of Psidium guajava leaves: phenolic compounds and inhibitory potential on digestive enzymes
Fonte: An. acad. bras. ciênc;89(3,supl):2155-2165, 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Leaves of Psidium guajava L. (guava) have been widely used in the popular way for prevention and treatment of various diseases. Thus, the objective of this study was to evaluate the inhibitory potential of leaves aqueous extract from three cultivars of P. guajava (Pedro Sato, Paluma and Século XXI) on α-amylase, α-glycosidase, lipase, and trypsin enzymes, in the presence or not of simulated gastric fluid and to determine the content of phenolic compounds by high performance liquid chromatography. All cultivars presented the same composition in phenolic compounds, but in different proportions. The compounds identified are gallic acid, epigallocatechin gallate, syringic acid, o-coumaric acid, resveratrol, quercetin, and catechin (which was the major compound in all the cultivars evaluated). In the absence of simulated gastric fluid, it was observed different inhibitions exercised by the leaves aqueous extracts from three cultivars of P. guajava on each enzyme. In presence of simulated gastric fluid, all cultivars showed increase in the inhibition of lipase and α-glycosidase, and decrease in inhibition of α-amylase and trypsin enzymes. These results indicate that P. guajava leaves aqueous extracts from all cultivars evaluated possess potential of use as an adjuvant in the treatment of obesity and other dyslipidemias.
Descritores: Extratos Vegetais/farmacologia
Extratos Vegetais/química
Folhas de Planta/química
Inibidores Enzimáticos/farmacologia
Antioxidantes/farmacologia
Obesidade/tratamento farmacológico
-Fenóis/análise
Água/análise
Tripsina/farmacologia
Cromatografia Líquida de Alta Pressão
Psidium/química
alfa-Amilases/farmacologia
alfa-Glucosidases/farmacologia
Lipase/farmacologia
Responsável: BR1.1 - BIREME


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Id: biblio-839159
Autor: Cansian, R L; Vanin, A B; Orlando, T; Piazza, S P; Puton, B M S; Cardoso, R I; Gonçalves, I L; Honaiser, T C; Paroul, N; Oliveira, D.
Título: Toxicity of clove essential oil and its ester eugenyl acetate against Artemia salina / Toxicidade do óleo essencial de cravo e seu éster acetato de eugenila contra Artemia salina
Fonte: Braz. j. biol;77(1):155-161, Jan-Mar. 2017. tab, graf.
Idioma: en.
Resumo: Abstract The production of compounds via enzymatic esterification has great scientific and technological interest due to the several inconveniences related to acid catalysis, mainly by these systems do not fit to the concept of “green chemistry”. Besides, natural products as clove oil present compounds with excellent biological potential. Bioactives compounds are often toxic at high doses. The evaluation of lethality in a less complex animal organism can be used to a monitoring simple and rapid, helping the identification of compounds with potential insecticide activity against larvae of insect vector of diseases. In this sense, the toxicity against Artemia salina of clove essential oil and its derivative eugenyl acetate obtained by enzymatic esterification using Novozym 435 as biocatalyst was evaluated. The conversion of eugenyl acetate synthesis was 95.6%. The results about the evaluation of toxicity against the microcrustacean Artemia salina demonstrated that both oil (LC50= 0.5993 µg.mL–1) and ester (LC50= 0.1178 µg.mL–1) presented high toxic potential, being the eugenyl acetate almost 5 times more toxic than clove essential oil. The results reported here shows the potential of employing clove oil and eugenyl acetate in insecticide formulations.

Resumo A produção de compostos via esterificação enzimática possui grande interesse científico e tecnológico devido às inúmeras inconveniências relacionadas com a catálise ácida, principalmente por estes sitemas não se adequarem ao atual termo “tecnologias limpas”. Além disso, produtos naturais como o óleo de cravo, apresentam compostos com excelentes potenciais biológicos. Compostos bioativos são quase sempre tóxicos em altas doses. A avaliação da letalidade em um organismo animal menos complexo pode ser usada para um monitoramento simples e rápido, servindo também para a identificação de compostos com potencial atividade inseticida contra larvas de insetos vetores de doenças. Neste sentido, foi determinada a toxicidade frente a Artemia salina do óleo essencial de cravo e do seu derivado acetato de eugenila obtido por esterificação enzimática com lipase Novozym 435. A conversão da reação de síntese de acetato de eugenila foi de 95,6%. Os resultados referentes à avaliação da toxicidade frente ao microcrustáceo Artemia salina demonstraram que tanto o óleo (LC50= 0,5993 µg.mL–1) quanto o éster (LC50= 0,1178 µg.mL–1) apresentam elevado potencial toxicológico, sendo que o éster apresenta aproximadamente 5 vezes mais toxicidade em relação ao óleo. Estes resultados demonstram o potencial emprego do óleo de cravo e de acetato de eugenila em formulações de inseticidas.
Descritores: Artemia/efeitos dos fármacos
Óleos Voláteis/toxicidade
Óleo de Cravo/toxicidade
Inseticidas/toxicidade
-Eugenol/análogos & derivados
Eugenol/síntese química
Eugenol/toxicidade
Relação Dose-Resposta a Droga
Esterificação/efeitos dos fármacos
Larva/efeitos dos fármacos
Lipase/toxicidade
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: lil-564587
Autor: Huerta, Doris; Acosta, Oscar; Miranda, Cecilia; Polo, Susan; Oré, Raquel; Bardales, Amelia; Pajuelo, Jaime.
Título: Relación del polimorfismo C-514T del gen de la lipasa hepática con indicadores nutricionales y lipoproteínas en una muestra poblacional peruana: una perspectiva nutrigenética / Relation of the hepatic lipase gene C-514T polymorphism with nutritional indicators and lipoproteins in a peruvian population sample: a nutrigenetic perspective
Fonte: An. Fac. Med. (Perú);69(4):244-249, oct.-dic. 2008. graf, tab.
Idioma: es.
Resumo: Introducción: Las enfermedades cardiovasculares son una de las principales causas de muerte en todo el mundo. El promotor del gen de la lipasa hepática presenta un polimorfismo funcional C-514T que se relaciona con la actividad de la enzima, la variación de los niveles de lipoproteínas y un posible riesgo para desarrollar enfermedades cardiovasculares. Objetivos: Establecer la relación del polimorfismo C-514T del promotor del gen de la lipasa hepática con indicadores nutricionales y los niveles de lipoproteínas plasmáticas en una muestra de peruanos saludables. Diseño: Estudio descriptivo, transversal, asociativo. Lugar: Centro de Investigación de Bioquímica y Nutrición Alberto Guzmán Barrón, Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Participantes: Noventiuna personas sanas de ambos sexos, cuyas edades fluctuaban entre 18 y 58 años, voluntarios con consentimiento informado. Intervenciones: Extracción del ADN genómico a partir de muestras sanguíneas según metodología estándar. Toma de medidas antropométricas, estableciéndose los indicadores nutricionales, determinación del perfil lipídico por el método enzimático. Análisis del polimorfismo C-514T mediante la técnica de PCR/RFLP, con primers específicos y digestión con la enzima de restricción NlaIII, detectándose los fragmentos de RFLP por electroforesis en gel de poliacrilamida (PAGE) y tinción con nitrato de plata. Principales medidas de resultados: Frecuencias genotípicas y alélicas del gende la lipasa hepática y relación con parámetros lipídicos y nutricionales. Resultados: Se encontró las frecuencias genotípicas CC=0,143; CT=0,593 y TT = 0,264, siendola distribución consistente con el equilibrio de Hardy-Weinberg (X2 =3,8024, g.l.=1, p = 0,086). Las frecuencias alélicas fueron alelo C = 0,4395 y el alelo T = 0,5605. Los niveles de colesterol, HDLc, LDLc, TG y los promedios de pliegue subcutáneo, el IMC y el porcentaje de grasa en los genotipos CC, CT y TT.

Introduction: Cardiovascular diseases are major causes de death in the world. The hepatic lipase (HL) gene promoter region presents a C-514T functional polymorphism related to enzyme activity, variation of lipoproteins levels and possible cardiovascular disease risk. Objectives: To determine the association of HL gene promoter region polymorphism with both nutritional indicators and lipoproteins levels in a healthy Peruvian sample. Design: Descriptive, transversal, associative study. Setting: Alberto Guzman Barron Biochemistry and Nutrition Research Center, Faculty of Medicine, Universidad Nacional Mayor de San Marcos. Participants: Ninety healthy male and female volunteers aged 18 to 58 years. Interventions: Genomic DNA was obtained from serum samples according to standard methodology. Anthropometric measurements and lipid profile byenzymatic methods were performed. Polymorphism C-514T in the HL gene was determined by polymerase chain reaction (PCR). PCR products were digested with NlaIII and fragments separated by polyacrilamyde gel electrophoresis (PAGE) and stained with silver nitrate. Main outcome measures: HL gene genotypes and alleles frequencies and relation with both lipid and nutritional parameters. Results: We found genotype frequencies CC=0,143; CT=0,593 and TT = 0,264, consistent with Hardy-Weinberg equilibrium (X2 =3,8024, g.l. = 1, p = 0,086). Alleles frequencies were C allele = 0,4395 and T allele = 0,5605. HDLc, LDLc, TAG cholesterol levels and subcutaneous fold, BMI and fat percentage averages in CC, CT and TT genotypes did not show significant differences (p > 0,05). Nevertheless, when T allele was analyzed alone (genotypes CT and TT) according to age and sex there were significant differences (p < 0,05) in some parameters.
Descritores: Doenças Cardiovasculares
Genética
Lipase
Lipoproteínas
Polimorfismo Genético
Ranunculaceae
Limites: Humanos
Masculino
Feminino
Adulto
Pessoa de Meia-Idade
Responsável: PE1.1 - Oficina Universitária de Biblioteca


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Id: lil-788974
Autor: Gururaj, P; Ramalingam, Subramanian; Devi, Ganesan Nandhini; Gautam, Pennathur.
Título: Process optimization for production and purification of a thermostable, organic solvent tolerant lipase from Acinetobacter sp. AU07
Fonte: Braz. j. microbiol;47(3):647-657, July-Sept. 2016. tab, graf.
Idioma: en.
Projeto: Department of Biotechnology, Government of India.
Resumo: ABSTRACT The purpose of this study was to isolate, purify and optimize the production conditions of an organic solvent tolerant and thermostable lipase from Acinetobacter sp. AU07 isolated from distillery waste. The lipase production was optimized by response surface methodology, and a maximum production of 14.5 U/mL was observed at 30 ºC and pH 7, using a 0.5% (v/v) inoculum, 2% (v/v) castor oil (inducer), and agitation 150 rpm. The optimized conditions from the shake flask experiments were validated in a 3 L lab scale bioreactor, and the lipase production increased to 48 U/mL. The enzyme was purified by ammonium sulfate precipitation and ion exchange chromatography and the overall yield was 36%. SDS-PAGE indicated a molecular weight of 45 kDa for the purified protein, and Matrix assisted laser desorption/ionization time of flight analysis of the purified lipase showed sequence similarity with GDSL family of lipases. The optimum temperature and pH for activity of the enzyme was found to be 50 ºC and 8.0, respectively. The lipase was completely inhibited by phenylmethylsulfonyl fluoride but minimal inhibition was observed when incubated with ethylenediaminetetraacetic acid and dithiothreitol. The enzyme was stable in the presence of non-polar hydrophobic solvents. Detergents like SDS inhibited enzyme activity; however, there was minimal loss of enzyme activity when incubated with hydrogen peroxide, Tween 80 and Triton X-100. The kinetic constants (Km and Vmax) revealed that the hydrolytic activity of the lipase was specific to moderate chain fatty acid esters. The Vmax, Km and Vmax/Km ratio of the enzyme were 16.98 U/mg, 0.51 mM, and 33.29, respectively when 4-nitrophenyl palmitate was used as a substrate.
Descritores: Compostos Orgânicos
Solventes
Proteínas de Bactérias/isolamento & purificação
Proteínas de Bactérias/biossíntese
Acinetobacter/enzimologia
Lipase/isolamento & purificação
Lipase/biossíntese
-Compostos Orgânicos/química
Solventes/química
Especificidade por Substrato
Temperatura
Proteínas de Bactérias/química
Estabilidade Enzimática
Cinética
Cromatografia por Troca Iônica
Ativação Enzimática
Espaço Extracelular/enzimologia
Concentração de Íons de Hidrogênio
Íons
Lipase/química
Lipólise
Metais
Peso Molecular
Responsável: BR1.1 - BIREME


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Id: lil-780837
Autor: Colla, Luciane Maria; Primaz, Andreiza Lazzarotto; Benedetti, Silvia; Loss, Raquel Aparecida; Lima, Marieli de; Reinehr, Christian Oliveira; Bertolin, Telma Elita; Costa, Jorge Alberto Vieira.
Título: Surface response methodology for the optimization of lipase production under submerged fermentation by filamentous fungi
Fonte: Braz. j. microbiol;47(2):461-467, Apr.-June 2016. tab, graf.
Idioma: en.
Resumo: Abstract A Plackett–Burman Factorial Design of 16 experiments was conducted to assess the influence of nine factors on the production of lipases by filamentous fungi. The factors investigated were bran type (used as the main carbon source), nitrogen source, nitrogen source concentration, inducer, inducer concentration, fungal strain (Aspergillus niger or Aspergillus flavus were selected as good lipase producers via submerged fermentation), pH and agitation. The concentration of the yeast extract and soybean oil and the pH had a significant effect (p < 0.05) on lipase production and were consecutively studied through a Full Factorial Design 23, with the concentration of yeast extract and pH being significant (p < 0.05). These variables were optimized using a central composite design, obtaining maximum lipolytic activities with the use of 45 g/L of yeast extract and pH 7.15. The statistical model showed a 94.12% correlation with the experimental data.
Descritores: Aspergillus flavus/metabolismo
Aspergillus niger/metabolismo
Microbiologia Industrial/métodos
Proteínas Fúngicas/biossíntese
Lipase/biossíntese
-Carbono/metabolismo
Meios de Cultura/metabolismo
Meios de Cultura/química
Fermentação
Nitrogênio/metabolismo
Responsável: BR1.1 - BIREME


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Id: biblio-964865
Autor: González, Yenny; González de García, Mirtha; Degen de Arrúa, Rosa; López, Marcelo; Bernal, Cynthia; Ayala, Juan; Yubero, Fátima.
Título: Morfología, anatomía estructural y actividad lipasa de la pulpa de "coco", Acrocomia aculeata(Jacq) Lodd. ex Mart.(Arecaceae) en función al tiempo de colecta / Morphology, structural anatomy and lipase activity in coconut pulp, Acrocomia aculeata(Jacq) Lodd.ex Mart.(Arecaceae) according to time of collection
Fonte: Rojasiana;17(1):73-80, 2018.
Idioma: es.
Descritores: Cocos/anatomia & histologia
Cocos/enzimologia
Óleo de Palmeira
-Fatores de Tempo
Qualidade dos Alimentos
Arecaceae/anatomia & histologia
Arecaceae/enzimologia
Lipase/metabolismo
Responsável: PY37.1 - Biblioteca


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Id: lil-520217
Autor: Parvathi, Ammini; Krishna, Kiran; Jose, Jiya; Joseph, Neetha; Nair, Santha.
Título: Biochemical and molecular characterization of Bacillus pumilus isolated from coastal environment in Cochin, India / Caracterização bioquímica e molecular de Bacillus pumilus isolado do ambiente costeiro de Cochin, Índia
Fonte: Braz. j. microbiol;40(2):269-275, Apr.-June 2009. ilus, tab.
Idioma: en.
Resumo: Bacillus species constitute a diverse group of bacteria widely distributed in soil and the aquatic environment. In this study, Bacillus strains isolated from the coastal environment of Cochin, India were identified by detailed conventional biochemical methods, fatty acid methyl ester (FAME) analysis and partial 16S rDNA sequencing. Analysis of the data revealed that Bacillus pumilus was the most predominant species in the region under study followed by B. cereus and B. sphaericus. The B. pumilus isolates were further characterized by arbitrarily primed PCR (AP-PCR), antibiotic sensitivity profiling and PCR screening for known toxin genes associated with Bacillus spp. All B. pumilus isolates were biochemically identical, exhibited high protease and lipase activity and uniformly sensitive to antibiotics tested in this study. One strain of B. pumilus harboured cereulide synthetase gene cesB of B. cereus which was indistinguishable from rest of the isolates biochemically and by AP-PCR. This study reports, for the first time, the presence of the emetic toxin gene cesB in B. pumilus.

As espécies de Bacillus constituem um grupo diversificado de bactérias amplamente distribuídas no solo e no ambiente aquático. Neste estudo, cepas de Bacillus isoladas do ambiente costeiro de Cochin, Índia, foram identificadas através de métodos bioquímicos convencionais, análise de ésteres metílicos de ácidos graxos (FAME) e sequenciamento de 16S rDNA. A análise dos dados revelou que Bacillus pumilus foi a espécie predominante na região estudada, seguido de B. cereus e B. sphaericus. Os isolados de B. pumilus foram caracterizados através da reação em cadeia da polimerase com primers arbitrários (AP-PCR), perfil de sensibilidade a antibióticos e triagem por PCR de genes de toxinas associadas com Bacillus spp. Todos os isolados de B. pumilus foram bioquimicamente idênticos, apresentaram elevada atividade de protease e lipase e foram uniformemente sensíveis aos antibióticos estudados. Um dos isolados de B. pumilus apresentou o gene cesB de B. cereus, que não foinão distinguível dos demais isolados por testes bioquímicos nem por AP-PCR. Este é o primeiro relato da presença do gene cesB da toxina eméticaem B. pumilus.
Descritores: Aspergillus flavus/genética
Bacillus/isolamento & purificação
Técnicas In Vitro
Lipase/genética
Peptídeo Hidrolases/genética
Pimenta/genética
Reação em Cadeia da Polimerase
Sequência de Bases
Ácidos Graxos/análise
-Ambiente Aquático
Métodos
Solo
Técnicas
Tipo de Publ: Relatório Técnico
Responsável: BR32.1 - Serviço de Biblioteca e Informação Biomédica


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Id: lil-633030
Autor: Berg, Gabriela; Brites, Fernando; Muzzio, María Luz; Zago, Valeria; López, Graciela; Benitez, María Belén; Gomez Rosso, Leonardo; Miksztowicz, Verónica; Cacciagiú, Leonardo; González, Ana Inés; Aisemberg, Laura; Schreier, Laura; Wikinski, Regina.
Título: Factores circulantes de injuria endotelial y procesos subendoteliales en mujeres postmenopáusicas sanas / Endothelial injuring factors and subendothelial events in healthy postmenopausal women
Fonte: Acta bioquím. clín. latinoam;41(4):499-510, oct.-dic. 2007. ilus, graf, tab.
Idioma: es.
Projeto: UBACyT; . ANPCyT. PICT 14299.
Resumo: La concentración elevada de lipoproteínas aterogénicas con apo B en mujeres posmenopáusicas (MPM), es un componente importante del mecanismo multifactorial causante de la enfermedad coronaria. En MPM sanas (n=30) en comparación con premenopáusicas (MpreM) (n=28), se evaluó el perfil lipoproteico incluyendo apoproteínas A-I y B, LDL pequeña y densa, composición y oxidabilidad de LDL, proteína transportadora de colesterol esterificado y lipasa hepática. Se determinaron los siguientes factores emergentes: homocisteína, fosfolipasa A2, ferritina, PCR-hs (alta sensibilidad) y fibronectina proveniente de la matriz extracelular. La insulino-resistencia fue evaluada por la circunferencia de cintura, el índice HOMA y el índice triglicéridos/colesterol-HDL. El índice de riesgo apo B/apoA-I fue significativamente mayor en MPM (p<0,0001). MPM presentaron mayor proporción de LDL pequeña y densa, la cual correlacionó con el aumento de actividad de lipasa hepática (p<0,005), y con marcadores de insulino-resistencia (p<0,05). Fosfolipasa A2 (p<0,05), homocisteína (p<0,005), ferritina (p<0,0001), PCR-hs (p<0,005) y fibronectina (p<0,05)) fueron mayores en MPM. La oxidabilidad de LDL no mostró diferencias significativas pero correlacionó positivamente con LDL pequeña y densa (p<0,01), fosfolipasa A2 (p<0,05), homocisteína (p<0,05), PCR-hs (p<0,04), fibronectina (p<0,05) y cintura (p<0,02). Luego de ajustar por la condición menopáusica, edad y cintura, la oxidabilidad de LDL permaneció asociada con LDL pequeña y densa (b:0,36, p=0,027), homocisteína (b:0,36, p<0,038), fibronectina (b:0,41 p=0,05) y cintura (b:0,35, p=0,047). En este estudio, la interacción de factores de riesgo aterogénico clásicos y no tradicionales sugiere una secuencia de eventos que comienzan con la injuria endotelial causada por homocisteína y LDL pequeña y densa, que penetra en subendotelio donde su oxidación es favorecida por la homocisteína. Se produciría un proceso inflamatorio, que cursa con aumento de PCR y ferritina. La fosfolipasa A2, proveniente de macrófagos, atravesaría el endotelio unida a la LDL modificada, y promueve la liberación de fibronectina desde la matriz extracelular. La estrecha interacción entre la injuria endotelial, inflamación e insulino-resistencia se observaría desde estadíos subclínicos de aterosclerosis en MPM sanas.

In postmenopausal women (PMW), high concentrations of atherogenic apoB lipoproteins is an important component of the multifactorial mechanism underlying a higher risk of coronary artery disease, as compared with premenopausal women (PreMW). Lipoprotein pattern, including apopoproteins A-I and B, LDL chemical composition and small dense LDL (sdLDL), hepatic lipase activity, circulating cholesterol transfer protein and LDL oxidability were assessed in PMW (n=30) in comparison to PreMW (n=28). The following endothelial injuring factors were measured: homocysteine, lipoprotein binding phospholipase A2 (LpPLA2), ferritin, hs-CRP and fibronectin coming from extracellular vascular matrix. Insulin-resistance was evaluated by waist circumference, HOMA and triglyceride/HDL-cholesterol. PMW showed higher apoB/apoA-I (p<0.0001) and a higher proportion of sdLDL which showed significant correlations with the increase in hepatic lipase activity (p<0.005) and insulin-resistance markers (p<0.05). LpPLA2 (p<0.05), homocysteine (p<0.005), hs-CRP (p<0.005), fibronectin (p<0.05) and ferritin (p<0.0001) were elevated in PMW. LDL oxidability showed no differences between groups, but was positively correlated with waist (p<0.02), homocysteine (p<0.05), fibronectin (p<0.05), hs-CRP (p<0.04), LpPLA2 (p<0.05) and sdLDL (p<0.01). After adjusting by age, menopausal condition and waist, LDL oxidability remained associated with homocysteine (b: 0,36) p<0,038), sdLDL (b: 0.36, p=0.027), waist (b: 0.35, p=0.047) and fibronectin (b: 0,41 p=0.05). In this study, the interaction of classic and emerging atherogenic risk factors would suggest a sequence of events starting with endothelial damage caused by homocysteine and sdLDL, promoting its passage into the subendothelial space where it is oxidatively modified, enhanced by homocysteine. The above mentioned inflammatory process takes place with an increase in circulating hs-CRP and ferritin. LpPLA2, coming from macrophages, passes through the endothelium bound to modified LDL, promoting a release of fibronectin from the subendothelial extracellular matrix. Results suggest that the close interaction among endothelial injury, inflammation and insulin resistance can be observed since subclinical atherosclerosis states in healthy PMW.
Descritores: Menopausa
Fibronectinas
Pós-Menopausa
Homocisteína
-Receptores da Fosfolipase A2
Lipase
Responsável: AR1.2 - Instituto de Investigaciónes Epidemiológicas



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