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1.
Front Cardiovasc Med ; 11: 1381520, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952543

RESUMO

In recent years, the role of macrophages as the primary cell type contributing to foam cell formation and atheroma plaque development has been widely acknowledged. However, it has been long recognized that diffuse intimal thickening (DIM), which precedes the formation of early fatty streaks in humans, primarily consists of lipid-loaded smooth muscle cells (SMCs) and their secreted proteoglycans. Recent studies have further supported the notion that SMCs constitute the majority of foam cells in advanced atherosclerotic plaques. Given that SMCs are a major component of the vascular wall, they serve as a significant source of microvesicles and exosomes, which have the potential to regulate the physiology of other vascular cells. Notably, more than half of the foam cells present in atherosclerotic lesions are of SMC origin. In this review, we describe several mechanisms underlying the formation of intimal foam-like cells in atherosclerotic plaques. Based on these mechanisms, we discuss novel therapeutic approaches that have been developed to regulate the generation of intimal foam-like cells. These innovative strategies hold promise for improving the management of atherosclerosis in the near future.

2.
Arch Soc Esp Oftalmol (Engl Ed) ; 94(7): 331-336, 2019 Jul.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31079987

RESUMO

OBJECTIVE: To propose the Intense Pulsed Light (IPL) therapy as a helpful supplementary treatment in patients with dry eye disease. MATERIAL AND METHODS: Retrospective cross sectional design. Medical records of patients in whom dry eye disease symptoms were not satisfactorily controlled with medical therapy alone and who underwent additional IPL with at least three sessions completed. Data were analyzed before therapy and 3weeks after its completion to asses improvement. Determination of symptoms, through a visual analog scale; tear film stability, through tear Break Up Time (tBUT); measurement of tear secretion, through Schirmer Test; and ocular surface staining with Van Bijsterveld score were evaluated. SPSS software and nonparametric analysis of repeated measures were used. The study was approved by the ethics committee. RESULTS: 50 eyes from 25 subjects were reviewed. There were 9 males (36%) and 16 females (64%), with a median age of 59years (IQR 52-64). The median of the symptoms scale was 8 (IQR 8-9) and 3 (IQR 2-4) before and after the therapy respectively (P<.05). The median of BUT was 4 (IQR 3-5) and 10 (IQR 8-11), Schirmer test was 13 (IQR 12-15) and 15 (IQR 13-20), and Van Bijsterveld score was 3 (RIC 3-4) and 2 (IQR 2-3) before and after the therapy respectively (P<.05, for all measurements). CONCLUSION: IPL treatment has excellent results regarding both: dry eye disease symptoms improvement and in office objective tests such as tBUT, Schirmer test and Van Bijsterveld score; IPL could be considered as an effective adjunct for dry eye disease.


Assuntos
Síndromes do Olho Seco/terapia , Terapia de Luz Pulsada Intensa , Terapia Combinada , Estudos Transversais , Resistência a Medicamentos , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/etiologia , Feminino , Humanos , Terapia de Luz Pulsada Intensa/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rosácea/complicações , Índice de Gravidade de Doença , Síndrome de Sjogren/complicações , Resultado do Tratamento
3.
Sci Rep ; 7(1): 47, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28246388

RESUMO

Using in vitro, in vivo and patient-based approaches, we investigated the potential of circulating microRNAs (miRNAs) as surrogate biomarkers of myocardial steatosis, a hallmark of diabetic cardiomyopathy. We analysed the cardiomyocyte-enriched miRNA signature in serum from patients with well-controlled type 2 diabetes and with verified absence of structural heart disease or inducible ischemia, and control volunteers of the same age range and BMI (N = 86), in serum from a high-fat diet-fed murine model, and in exosomes from lipid-loaded HL-1 cardiomyocytes. Circulating miR-1 and miR-133a levels were robustly associated with myocardial steatosis in type 2 diabetes patients, independently of confounding factors in both linear and logistic regression analyses (P < 0.050 for all models). Similar to myocardial steatosis, miR-133a levels were increased in type 2 diabetes patients as compared with healthy subjects (P < 0.050). Circulating miR-1 and miR-133a levels were significantly elevated in high-fat diet-fed mice (P < 0.050), which showed higher myocardial steatosis, as compared with control animals. miR-1 and miR-133a levels were higher in exosomes released from lipid-loaded HL-1 cardiomyocytes (P < 0.050). Circulating miR-1 and miR-133a are independent predictors of myocardial steatosis. Our results highlight the value of circulating miRNAs as diagnostic tools for subclinical diabetic cardiomyopathy.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Cardiomiopatias Diabéticas/sangue , MicroRNAs/sangue , Miocárdio/patologia , Idoso , Animais , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/complicações , Cardiomiopatias Diabéticas/etiologia , Dieta Hiperlipídica , Exossomos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Miócitos Cardíacos/patologia , Espectroscopia de Prótons por Ressonância Magnética
4.
Clin Exp Immunol ; 186(3): 292-303, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27571306

RESUMO

Apolipoprotein E (ApoE) deficiency promoted an exacerbation of autoimmune arthritis in mice by inducing proinflammatory immune responses. In this study we analysed the contribution of hypercholesterolaemia and/or the absence of ApoE anti-inflammatory properties, unrelated to its function in the control of cholesterol metabolism, towards the acceleration of arthritis in these mutant animals. The induction and severity of collagen type II-induced arthritis (CIA) were compared for B10.RIII wild-type (WT), B10.RIII.ApoE+/- , B10.RIII.ApoE-/- and B10.RIII.low-density lipoprotein receptor (LDLR-/- ) mice with different concentrations of circulating ApoE and cholesterol. A 50-70% reduction in serum levels of ApoE was observed in heterozygous B10.RIII.ApoE+/- mice in comparison to B10.RIII.WT, although both strains of mice exhibited similar circulating lipid profiles. This ApoE reduction was associated with an increased CIA severity that remained lower than in homozygous B10.RIII.ApoE-/- mice. An important rise in circulating ApoE concentration was observed in hypercholesterolaemic B10.RIII.LDLR-/- mice fed with a normal chow diet, and both parameters increased further with an atherogenic hypercholesterolaemic diet. However, the severity of CIA in B10.RIII.LDLR-/- mice was similar to that of B10.RIII.WT controls. In conclusion, by comparing the evolution of CIA between several strains of mutant mice with different levels of serum ApoE and cholesterol, our results demonstrate that both hypercholesterolaemia and ApoE regulate the intensity of in-vivo systemic autoimmune responses.


Assuntos
Apolipoproteínas E/metabolismo , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Colesterol/metabolismo , Imunomodulação , Animais , Apolipoproteínas E/sangue , Apolipoproteínas E/genética , Artrite Experimental/genética , Artrite Experimental/patologia , Doenças Autoimunes/genética , Doenças Autoimunes/patologia , Biomarcadores , Colesterol/sangue , HDL-Colesterol/sangue , HDL-Colesterol/metabolismo , Modelos Animais de Doenças , Estudos de Associação Genética , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/genética , Hipercolesterolemia/imunologia , Hipercolesterolemia/metabolismo , Camundongos , Camundongos Knockout , Mutação , Índice de Gravidade de Doença
5.
Rev Esp Anestesiol Reanim ; 58(8): 477-84, 2011 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-22141215

RESUMO

OBJECTIVES: Our main objective was to determine the reasons why residents chose to specialize in anesthesiology and postoperative critical care in the autonomous community of Madrid. We also wished to know if prior contact with this specialty influenced their choice, if those who chose it as a second specialization differed from those who were doing a first residency, what expectations the residents had and if they had been met, and if they were satisfied with their training. MATERIAL AND METHODS: Survey of all residents in anesthesiology and postoperative critical care medicine in the community of Madrid between November 2008 and February 2010. The questionnaire items covered demographic data, prior specialty training, undergraduate contact with the specialty, reasons for choosing this specialty (technical, social, or employment-related interests), satisfaction, and expectations met. RESULTS: We received 89 valid questionnaires, a sample that represented 35% of the residents. The reasons expressed most often were learning and performing techniques (97.8%); that the specialty was dynamic, with broad theoretical and practical content (98.9%), and an interest in providing critical care (93.3%). These 3 reasons were considered important or very important by most of the respondents; 55.8% considered that learning and carrying out techniques was the most important reason. All the respondents who had previously done specialty training said they were dissatisfied. Prior contact with the specialty was associated with having different reasons and interests, such as an interest in pain (F = .037) or emulating a role model (P = .014). CONCLUSIONS: The specialty's mix of theoretical and practical content and the chance to perform techniques and provide critical care are the features the residents find most attractive. Residents who already have another specialty are less satisfied and their expectations are not as well met.


Assuntos
Anestesiologia/educação , Escolha da Profissão , Cuidados Críticos , Cuidados Pós-Operatórios/educação , Feminino , Humanos , Internato e Residência , Masculino , Motivação , Espanha , Inquéritos e Questionários , População Urbana
6.
Rev. esp. anestesiol. reanim ; 58(8): 477-484, oct. 2011. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-91276

RESUMO

Objetivos: El objetivo principal fue conocer las motivaciones que han determinado la elección de la especialidad en Anestesiología y Reanimación en la Comunidad de Madrid y determinar si el conocimiento o contacto previo con la especialidad contribuía a la elección de la misma, ver si existían diferencias en las motivaciones principales del grupo que elige la especialidad por primera vez, con respecto a los que lo hacen como segunda especialidad y saber cuáles eran sus expectativas y si éstas se habían cumplido, además de conocer el grado de satisfacción global. Material y métodos: Encuesta dirigida a todos los residentes de Anestesiología y Reanimación de la Comunidad de Madrid entre noviembre de 2008 y febrero de 2010. La encuesta incluía datos demográficos, especialidad previa, contacto pregraduado, motivos de elección (técnicos, sociales, laborales, satisfacción obtenida y expectativas cumplidas). Resultados: Se obtuvieron 89 encuestas válidas (35% de repuestas). Los aspectos más frecuentemente valorados fueron: el desarrollo y realización de técnicas (97,8%), el concepto de especialidad dinámica y con amplio contenido teórico práctico (98,9%), la valoración y el tratamiento del paciente crítico (93,3%). Asimismo estas tres razones las consideraron entre importantes y muy importantes en la valoración cuantitativa por la mayoría de los encuestados, siendo lo más importante para el 55,8% la realización y desarrollo de técnicas. El 100% de los que tenían especialidad previa, se definieron insatisfechos. El conocimiento previo de la especialidad establece diferencias en las motivaciones e intereses, como el interés por el dolor (p = 0,037) o el modelo profesional a emular (p = 0,014). Conclusiones. Lo que más atrae a los residentes es el contenido teórico práctico, la posibilidad de realizar técnicas y la valoración y tratamiento del paciente crítico. Los residentes con otra especialidad están menos satisfechos y sus expectativas menos cumplidas que el resto(AU)


Objectives: Our main objective was to determine the reasons why residents chose to specialize in anesthesiology and postoperative critical care in the autonomous community of Madrid. We also wished to know if prior contact with this specialty influenced their choice, if those who chose it as a second specialization differed from those who were doing a first residency, what expectations the residents had and if they had been met, and if they were satisfied with their training. Material and methods: Survey of all residents in anesthesiology and postoperative critical care medicine in the community of Madrid between November 2008 and February 2010. The questionnaire items covered demographic data, prior specialty training, undergraduate contact with the specialty, reasons for choosing this specialty (technical, social, or employment-related interests), satisfaction, and expectations met. Results: We received 89 valid questionnaires, a sample that represented 35% of the residents. The reasons expressed most often were learning and performing techniques (97.8%); that the specialty was dynamic, with broad theoretical and practical content (98.9%), and an interest in providing critical care (93.3%). These 3 reasons were considered important or very important by most of the respondents; 55.8% considered that learning and carrying out techniques was the most important reason. All the respondents who had previously done specialty training said they were dissatisfied. Prior contact with the specialty was associated with having different reasons and interests, such as an interest in pain (P=.037) or emulating a role model (P=.014). Conclusions: The specialty's mix of theoretical and practical content and the chance to perform techniques and provide critical care are the features the residents find most attractive. Residents who already have another specialty are less satisfied and their expectations are not as well met(AU)


Assuntos
Humanos , Masculino , Feminino , Anestesiologia/educação , Internato e Residência , Internato e Residência/organização & administração , Anestesiologia , Internato e Residência/tendências , Enquete Socioeconômica
7.
Br J Nutr ; 103(2): 153-60, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19822032

RESUMO

Disodium ascorbyl phytostanol phosphate (FM-VP4) is a synthetic compound derived from sitostanol and campestanol that has proved to be efficient as a cholesterol-lowering therapy in mice and human subjects. However, the mechanism of action of FM-VP4 remains unknown. The present study tests the ability of FM-VP4 to alter intestinal and liver cholesterol homeostasis in mice. Female C57BL/6J mice were fed either a control chow or a 2 % FM-VP4-enriched diet for 4 weeks. FM-VP4 reduced the in vivo net intestinal cholesterol absorption and plasma and liver cholesterol concentrations by 2.2-, 1.5- and 1.6-fold, respectively, compared with control mice. Furthermore, FM-VP4 also showed an impact on bile acid homeostasis. In FM-VP4 mice, liver and intestinal bile acid content was increased by 1.3- and 2.3-fold, respectively, whereas faecal bile acid output was 3.3-fold lower. FM-VP4 also increased the intestinal absorption of orally administered [3H]taurocholic acid to small intestine in vivo. Inhibition of intestinal cholesterol absorption by FM-VP4 was not mediated via transcriptional increases in intestine liver X receptor (LXR)-alpha, adenosine triphosphate-binding cassette transporter (ABC)-A1, ABCG5/G8 nor to decreases in intestinal Niemann-Pick C1-like 1 (NPC1L1) expression. In contrast, FM-VP4 up-regulated liver LXRalpha, ABCA1, ABCG5, scavenger receptor class BI (SR-BI) and hydroxymethylglutaryl coenzyme A reductase (HMGCoA-R) gene expression, whereas it down-regulated several farnesoid X receptor (FXR)-target genes such as cytochrome P450 family 7 subfamily A polypeptide 1 (CYP7A1) and Na+/taurocholate co-transporter polypeptide (NTCP). In conclusion, FM-VP4 reduced intestinal cholesterol absorption, plasma and liver cholesterol and affected bile acid homeostasis by inducing bile acid intestinal reabsorption and changed the liver expression of genes that play an essential role in cholesterol homeostasis. This is the first phytosterol or stanol that affects bile acid metabolism and lowers plasma cholesterol levels in normocholesterolaemic mice.


Assuntos
Circulação Hepática/efeitos dos fármacos , Fitosteróis/farmacologia , Animais , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Colesterol/metabolismo , Ingestão de Energia , Humanos , Absorção Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/fisiologia , Fígado/efeitos dos fármacos , Fígado/fisiologia , Circulação Hepática/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA/genética , RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Metabolism ; 57(11): 1497-501, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18940385

RESUMO

Most studies have focused on the cholesterol-lowering activity of phytosterols; however, other biological actions have also been attributed to these plant compounds. In this study, we investigated whether phytosterols could delay (progression phase) and/or reverse (regression phase) insulin resistance or type 2 diabetes mellitus in an experimental mouse model of diet-induced obesity, insulin resistance, and diabetes. Body mass, plasma lipid levels, insulin resistance, and hyperglycemia were determined. Phytosterol intake did not improve these metabolic parameters. Therefore, we were unable to substantiate any protective effect of phytosterol intake on diabetes development or regression in the mouse model used.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Gorduras na Dieta/administração & dosagem , Resistência à Insulina , Obesidade/prevenção & controle , Fitosteróis/farmacologia , Animais , Colesterol/sangue , Diabetes Mellitus Tipo 2/etiologia , Suscetibilidade a Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia
9.
Chemosphere ; 61(5): 711-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16219505

RESUMO

The effect of the consecutive annual additions of pig slurry at rates of 0 (control), 90 and 150 m3 ha(-1) y(-1) over a 4-year period on the binding affinity for Cu(II) of soil humic acids (HAs) and fulvic acids (FAs) was investigated in a field plot experiment under semiarid conditions. A ligand potentiometric titration method and a single site model were used for determining the Cu(II) complexing capacities and the stability constants of Cu(II) complexes of HAs and FAs isolated from pig slurry and control and amended soils. The HAs complexing capacities and stability constants were larger than those of the corresponding FA fractions. With respect to the control soil HA, pig-slurry HA was characterized by a much smaller binding capacity and stability constant. Amendment with pig slurry decreased the binding affinity of soil HAs. Similar to the corresponding HAs, the binding affinity of pig-slurry FA was much smaller while that of amended-soil FAs were slightly smaller when compared to the control soil FA. The latter effect was, however, more evident with increasing the amount of pig slurry applied to soil per year and the number of years of pig slurry application.


Assuntos
Benzopiranos/química , Cobre/química , Substâncias Húmicas , Esterco , Poluentes do Solo , Animais , Fertilizantes , Solo , Suínos
11.
J Lipid Res ; 42(11): 1727-39, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11714842

RESUMO

Our understanding of apolipoprotein A-II (apoA-II) physiology is much more limited than that of apoA-I. However, important and rather surprising advances have been produced, mainly through analysis of genetically modified mice. These results reveal a positive association of apoA-II with FFA and VLDL triglyceride plasma concentrations; however, whether this is due to increased VLDL synthesis or to decreased VLDL catabolism remains a matter of controversy. As apoA-II-deficient mice present a phenotype of insulin hypersensitivity, a function of apoA-II in regulating FFA metabolism seems likely. Studies of human beings have shown the apoA-II locus to be a determinant of FFA plasma levels, and several genome-wide searches of different populations with type 2 diabetes have found linkage to an apoA-II intragenic marker, making apoA-II an attractive candidate gene for this disease. The increased concentration of apoB-containing lipoproteins present in apoA-II transgenic mice explains, in part, why these animals present increased atherosclerosis susceptibility. In addition, apoA-II transgenic mice also present impairment of two major HDL antiatherogenic functions: reverse cholesterol transport and protection of LDL oxidative modification. The apoA-II locus has also been suggested as an important genetic determinant of HDL cholesterol concentration, even though there is a major species-specific difference between the effects of mouse and human apoA-II. As antagonizing apoA-I antiatherogenic actions can hardly be considered the apoA-II function in HDL, this remains a topic for future investigations. We suggest that the existence of apoA-II or apoA-I in HDL could be an important signal for specific interaction with HDL receptors such as cubilin or heat shock protein 60.


Assuntos
Apolipoproteína A-II/fisiologia , Arteriosclerose/genética , Metabolismo dos Lipídeos , Animais , Apolipoproteína A-II/química , Apolipoproteína A-II/deficiência , Apolipoproteína A-II/genética , Apolipoproteínas B/sangue , Transporte Biológico , Colesterol/metabolismo , HDL-Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Peroxidação de Lipídeos , Lipoproteínas VLDL/sangue , Camundongos , Camundongos Transgênicos , Triglicerídeos/sangue
12.
J Lipid Res ; 42(2): 241-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11181754

RESUMO

Apolipoprotein (apo)A-II is a major high density lipoprotein (HDL) protein; however, its role in lipoprotein metabolism is largely unknown. Transgenic (Tg) mice that overexpress human apoA-II present functional lecithin: cholesterol acyltransferase deficiency, HDL deficiency, hypertriglyceridemia and, when fed an atherogenic diet, increased non-HDL cholesterol and increased susceptibility to atherosclerosis. In contrast to humans, mice do not present cholesteryl ester transfer protein (CETP) activity in plasma. To study the in vivo interaction of these two proteins, we crossbred human apoA-II and CETP-Tg mice. CETP x apoA-II-Tg mice fed an atherogenic diet, compared with CETP-Tg mice presented a 2-fold decrease in HDL cholesterol and a quantitatively similar increase in total plasma cholesterol and percentage of free cholesterol, non-HDL cholesterol, and free fatty acids, together with a remarkable 112-fold increase in plasma triglycerides. Plasma triglycerides in CETP x apoA-II-Tg mice were mainly associated with very low density lipoproteins (VLDL), which were also enriched in protein content, and resulted from a combination of higher production rate compared with both of their progenitors and non-Tg control mice, and decreased catabolism compared only with CETP-Tg mice. These results show CETP x apoA-II-Tg mice to be a good model with which to study mechanisms leading to VLDL overproduction and suggest that CETP and, in particular apoA-II, may play a role in the regulation of VLDL metabolism.


Assuntos
Apolipoproteína A-II/metabolismo , Proteínas de Transporte/fisiologia , Glicoproteínas , Lipoproteínas VLDL/biossíntese , Animais , Proteínas de Transporte/genética , Proteínas de Transferência de Ésteres de Colesterol , Cromatografia Líquida , Feminino , Humanos , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatidilcolina-Esterol O-Aciltransferase/sangue
13.
Biochim Biophys Acta ; 1488(3): 233-44, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11082533

RESUMO

We investigated the mechanisms that lead to combined hyperlipidemia in transgenic mice that overexpress human apolipoprotein (apo) A-II (line 11.1). The 11.1 transgenic mice develop pronounced hypertriglyceridemia, and a moderate increase in free fatty acid (FFA) and plasma cholesterol, especially when fed a high-fat/high-cholesterol diet. Post-heparin plasma lipoprotein lipase and hepatic lipase activities (using artificial or natural autologous substrates), the decay of plasma triglycerides with fasting, and the fractional catabolic rate of the radiolabeled VLDL-triglyceride (both fasting and postprandial) were similar in 11. 1 transgenic mice and in control mice. In contrast, a 2.5-fold increase in hepatic VLDL-triglyceride production was observed in 11. 1 transgenic mice in a period of 2 h in which blood lipolysis was inhibited. This increased synthesis of hepatic VLDL-triglyceride used preformed FFA rather than FFA of de novo hepatic synthesis. The 11.1 transgenic mice also presented reduced epididymal/parametrial white adipose tissue weight (1.5-fold), increased rate of epididymal/parametrial hormone-sensitive lipase-mediated lipolysis (1.2-fold) and an increase in cholesterol and, especially, in triglyceride liver content, suggesting an enhanced mobilization of fat as the source of preformed FFA reaching the liver. Increased plasma FFA was reverted by insulin, demonstrating that 11.1 transgenic mice are not insulin resistant. We conclude that the overexpression of human apoA-II in transgenic mice induces combined hyperlipidemia through an increase in VLDL production. These mice will be useful in the study of molecular mechanisms that regulate the overproduction of VLDL, a situation of major pathophysiological interest since it is the basic mechanism underlying familial combined hyperlipidemia.


Assuntos
Apolipoproteína A-II/genética , Gorduras na Dieta/administração & dosagem , Hiperlipidemia Familiar Combinada/genética , Lipoproteínas VLDL/biossíntese , Animais , Apolipoproteína A-II/biossíntese , Apolipoproteína A-II/sangue , Glicemia , Colesterol na Dieta/administração & dosagem , Ácidos Graxos não Esterificados/sangue , Feminino , Privação de Alimentos , Regulação da Expressão Gênica , Teste de Tolerância a Glucose , Humanos , Hiperlipidemia Familiar Combinada/sangue , Insulina/sangue , Resistência à Insulina , Lipólise , Lipoproteínas VLDL/sangue , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Fatores de Tempo , Triglicerídeos/sangue
14.
J Lipid Res ; 41(8): 1328-38, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10946021

RESUMO

Familial combined hyperlipidemia (FCHL) is a common inherited hyperlipidemia and a major risk factor for atherothrombotic cardiovascular disease. The cause(s) leading to FCHL are largely unknown, but the existence of unidentified "major" genes that would increase VLDL production and of "modifier" genes that would influence the phenotype of the disease has been proposed. Expression of apolipoprotein A-II (apoA-II), a high density lipoprotein (HDL) of unknown function, in transgenic mice produced increased concentration of apoB-containing lipoproteins and decreased HDL. Here we show that expression of human apoA-II in apoE-deficient mice induces a dose-dependent increase in VLDL, resulting in plasma triglyceride elevations of up to 24-fold in a mouse line that has 2-fold the concentration of human apoA-II of normolipidemic humans, as well as other well-known characteristics of FCHL: increased concentrations of cholesterol, triglyceride, and apoB in very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL) and low density lipoprotein (LDL), reduced HDL cholesterol, normal lipoprotein lipase and hepatic lipase activities, increased production of VLDL triglycerides, and increased susceptibility to atherosclerosis. However, FCHL patients do not have plasma concentrations of human apoA-II as high as those of apoE-deficient mice overexpressing human apoA-II, and the apoA-II gene has not been linked to FCHL in genome-wide scans. Therefore, the apoA-II gene could be a "modifier" FCHL gene influencing the phenotype of the disease in some individuals through unkown mechanisms including an action on a "major" FCHL gene. We conclude that apoE-deficient mice overexpressing human apoA-II constitute useful animal models with which to study the mechanisms leading to overproduction of VLDL, and that apoA-II may function to regulate VLDL production.


Assuntos
Apolipoproteína A-II/genética , Apolipoproteínas E/deficiência , Expressão Gênica , Hiperlipidemia Familiar Combinada/genética , Animais , Apolipoproteínas B/sangue , Arteriosclerose/genética , Glicemia/análise , Peso Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Predisposição Genética para Doença , Humanos , Insulina/sangue , Lipase/sangue , Lipólise , Lipoproteínas/sangue , Lipoproteínas IDL , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Camundongos , Camundongos Transgênicos , Triglicerídeos/sangue
16.
Metabolism ; 48(4): 415-21, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10206431

RESUMO

We have developed several lines of transgenic animals that overexpress different levels of human apolipoprotein A-II (apoA-II). The 11.1 transgenic line has human apoA-II in plasma at threefold the level in normolipidemic humans and a functional lecithin:cholesterol acyltransferase (LCAT) deficiency. The latter is a biochemical phenotype similar to that of fish-eye disease (FED), which is characterized by free cholesterol (FC) and phospholipid accumulation in the cornea, leading to opacity and impaired vision. To assess whether the metabolic alterations in these mice also lead to lipid accumulation in the cornea, we fed them on a long-term regular chow or high-fat/high-cholesterol (HF/HC) diet. The 11.1 transgenic mice showed a moderate accumulation of FC in the cornea, but only when fed the regular chow diet. This FC accumulation was less severe than the accumulation described in FED, which may explain the lack of corneal opacity in these mice. Electron microscopy and immunoblotting analysis of the cornea of 11.1 transgenic mice in comparison to control mice showed (1) a mild but nevertheless more intense intracytoplasmatic lipid particle deposition in the epithelial cells and (2) a decrease of immunoreactive apoA-I in the area of Bowman's layer and at the superficial stroma. The serum capacity to cause cholesterol efflux from rat fibroblasts was decreased in 11.1 transgenic mice, but only in those fed a regular chow diet. We conclude that 11.1 human apoA-II transgenic mice may be a useful model for studies of early lipid deposition in the cornea and its possible prevention.


Assuntos
Apolipoproteína A-II/metabolismo , Colesterol/metabolismo , Córnea/metabolismo , Deficiência da Lecitina Colesterol Aciltransferase/metabolismo , Animais , Apolipoproteína A-II/genética , Western Blotting , Células Cultivadas , Colesterol/sangue , Colesterol/genética , Córnea/ultraestrutura , Humanos , Deficiência da Lecitina Colesterol Aciltransferase/genética , Lipídeos/sangue , Lipoproteínas/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Eletrônica
17.
J Lipid Res ; 39(2): 457-62, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9580110

RESUMO

We report on the effect of human apolipoprotein (apo) A-II transgene expression on atherosclerosis susceptibility in two transgenic lines (25.3 and 11.1) whose plasma human apoA-II concentrations (approximately 23 and 96 mg/dl, respectively) span the normal range in humans. After 9 months of an atherogenic diet, 25.3 and 11.1 transgenic mice developed aortic atherosclerotic lesions that were approximately 1.7- and 7-fold, respectively, more extensive than those of non-transgenic control mice. However, there was no difference in the area of atherosclerosis of transgenic and control mice when fed a regular chow diet This contrasts with the findings in murine apoA-II transgenic mice and provides evidence of a species-specific characteristic that could be of relevance with respect to the high fat intake diets common in most industrialized countries. A possible mechanism of the pro-atherogenic action of human apoA-II could be the inhibition of reverse cholesterol transport and, in support of this, we observed an impairment of apoA-I-HDL particle interconversion in the plasma of 11.1 transgenic mice caused, at least in part, by a marked decrease in the endogenous lecithin:cholesterol acyltransferase activity.


Assuntos
Apolipoproteína A-II/genética , Apolipoproteína A-II/metabolismo , Arteriosclerose/genética , Expressão Gênica , Animais , Doenças da Aorta/etiologia , Doenças da Aorta/genética , Doenças da Aorta/patologia , Apolipoproteína A-I/metabolismo , Arteriosclerose/etiologia , Arteriosclerose/patologia , Dieta Aterogênica , Humanos , Lipoproteínas HDL/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatidilcolina-Esterol O-Aciltransferase/sangue , Especificidade da Espécie
18.
Ann Allergy ; 70(1): 23-5, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8424592

RESUMO

Asthmatic patients frequently develop wheezing after respiratory tract infection. Mycoplasma pneumoniae causes respiratory tract infections in children and in adults. The purpose of this study was to determine the frequency of recovery of M. pneumoniae from patients with asthma. Seventy-seven patients with asthma and 88 persons without asthma or any other respiratory tract disease (controls) were included in the study. Ages ranged from 8 months to 31 years. Throat swabs were taken and deposited in egg yolk broth with methylene blue in order to isolate M. pneumoniae. The bacterium was identified using inhibition of growth with homologous antiserum. The isolation rate in patients with asthma was 24.7% while that in controls was 5.7% (P < .01). The results suggest that M. pneumoniae colonizes a higher percentage of patients with asthma than controls and could possibly have induced the wheezing.


Assuntos
Asma/microbiologia , Mycoplasma pneumoniae/isolamento & purificação , Adolescente , Adulto , Asma/complicações , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Pulmão/microbiologia , Masculino , Pneumonia por Mycoplasma/complicações
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