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1.
Diab Vasc Dis Res ; 19(1): 14791641221085269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35343275

RESUMO

Advanced glycation end products (AGEs) are independently related to cardiovascular disease (CVD) and favor cholesterol and oxysterol accumulation in macrophage foam cells. Soluble RAGE (sRAGE) impairs cellular AGE signaling alleviating the deleterious effects of AGE in atherogenesis. The association between plasma AGEs and sRAGE with the content of cholesterol, markers of cholesterol synthesis and absorption, and oxysterols in atherosclerotic plaques was evaluated in subjects undergoing carotid endarterectomy.Plasma and carotid plaques were obtained from symptomatic (n = 23) and asymptomatic subjects (n = 40). Lipids from plaques were extracted and sterols (oxysterols, cholesterol, desmosterol, lathosterol, sitosterol, and campesterol) were determined by using gas chromatography/mass spectrometry. Plasma total AGEs and pentosidine were measured by using fluorimetry and sRAGE by using ELISA.In symptomatic subjects´ atherosclerotic plaques, an increased amount of cholesterol (3x) and oxysterols [7 α-hydroxycholesterol (1.4x); 7 ß-hydroxycholesterol (1.2x); 25-hydroxycholesterol (1.3x); 24-hydroxycholesterol (2.7x), and 27-hydroxycholesterol, (1.15x)], with exception to 7 ketocholesterol, were found in comparison to asymptomatic individuals. Plasma total AGEs and pentosidine significantly and positively correlated to sterols accumulated in the atherosclerotic lesion, including cholesterol, desmosterol, campesterol, sitosterol, and oxysterols. On the other hand, sRAGE inversely correlated to total AGEs and pentosidine in plasma, and with major species of oxysterols, cholesterol, and markers of cholesterol synthesis and absorption in the atherosclerotic lesion. In multiple regression analyses, it was observed a significant inverse correlation between sRAGE and 24-hydroxycholesterol and desmosterol, and a positive significant correlation between pentosidine and 24-hydroxycholesterol, 27-hydroxycholesterol, and campesterol.In conclusion, the plasma concentration of AGEs and sRAGE is a tool to predict the accumulation of sterols in atherosclerotic lesions in symptomatic and asymptomatic individuals, helping to prevent and improve the management of acute cardiovascular complications.


Assuntos
Aterosclerose , Placa Aterosclerótica , Produtos Finais de Glicação Avançada , Humanos , Receptor para Produtos Finais de Glicação Avançada , Esteróis
2.
Metabolism ; 114: 154429, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166579

RESUMO

OBJECTIVE: The systemic function of CETP has been well characterized. CETP plasma activity reduces HDL cholesterol and thus increases the risk of atherosclerosis. Here, we investigated whether CETP expression modulate adiposity. METHODS: Body adiposity and energy metabolism related assays and gene/protein expression were compared in CETP transgenic and non-transgenic mice and in hamsters treated with CETP neutralizing antibody. RESULTS: We found that transgenic mice expressing human CETP present less white adipose tissue mass and lower leptinemia than nontransgenic (NTg) littermates. No differences were found in physical activity, food intake, fat fecal excretion, lipogenesis or exogenous lipid accumulation in adipose depots. Nonetheless, adipose lipolysis rates and whole-body energy expenditure were elevated in CETP mice. In accordance, lipolysis-related gene expression and protein content were increased in visceral and brown adipose tissue (BAT). In addition, we verified increased BAT temperature and oxygen consumption. These results were confirmed in two other animal models: 1) hamsters treated with CETP neutralizing antibody and 2) an independent line of transgenic mice expressing simian CETP. CONCLUSIONS: These findings reveal a novel anti-adipogenic role for CETP.


Assuntos
Tecido Adiposo Marrom/metabolismo , Adiposidade/fisiologia , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Lipólise/fisiologia , Fígado/metabolismo , Animais , Anticorpos Neutralizantes , Proteínas de Transferência de Ésteres de Colesterol/genética , Cricetinae , Ingestão de Alimentos/fisiologia , Metabolismo Energético/fisiologia , Leptina/sangue , Camundongos , Camundongos Transgênicos , Atividade Motora/fisiologia
3.
J Physiol Biochem ; 76(3): 437-443, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32557226

RESUMO

Monogenic familial hypercholesterolemia is characterized by impaired cellular uptake of apolipoprotein B containing lipoproteins. However, its consequences on whole-body cholesterol metabolism are unclear. We investigated cholesterol metabolism in wild-type mice (control) and in knockout (KO) mice for the low-density lipoprotein receptor (LDLR-KO) and for apolipoprotein E (apoE-KO) containing the genetic basis of the C57BL/6J mice, under a cholesterol-free diet. Cholesterol and "non-cholesterol" sterols (cholestanol, desmosterol, and lathosterol) were measured in plasma, tissues, as well as in feces as cholesterol and its bacterial modified products (neutral sterols) using gas chromatography/mass spectrometry, and bile acids were measured by an enzymatic method. Compared to controls, LDLR-KO mice have elevated plasma and whole-body cholesterol concentrations, but total fecal sterols are not modified, characterizing unaltered body cholesterol synthesis together with impaired body cholesterol excretion. ApoE-KO mice presented the highest concentrations of plasma cholesterol, whole-body cholesterol, cholestanol, total fecal sterols, and cholestanol, compatible with high cholesterol synthesis rate; the latter seems attributed to elevated body desmosterol (Bloch cholesterol synthesis pathway). Nonetheless, whole-body lathosterol (Kandutsch-Russel cholesterol synthesis pathway) decreased in both KO models, likely explaining the diminished fecal bile acids. We have demonstrated for the first time quantitative changes of cholesterol metabolism in experimental mouse models that explain differences between LDLR-KO and apoE-KO mice. These findings contribute to elucidate the metabolism of cholesterol in human hypercholesterolemia of genetic origin.


Assuntos
Colestadienóis , Colesterol , Hipercolesterolemia/metabolismo , Metabolismo dos Lipídeos , Animais , Colestadienóis/sangue , Colestadienóis/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE
4.
Eur Arch Psychiatry Clin Neurosci ; 268(5): 501-507, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28861608

RESUMO

Cholesterol is an essential component in the structure and function of cell membranes and has been associated with the major pathological signatures of Alzheimer's disease (AD). To maintain brain cholesterol homeostasis, it is converted into 24(S)-hydroxycholesterol (24OHC) which can be driven through the blood-brain barrier. Several studies have already described a decrease in 24OHC and an increase of 27(S)-hydroxycholesterol (27OHC) in AD, as a reflection of disease burden, the loss of metabolically active neurons and the degree of structural atrophy. It is also well known that peripheral cholesterol is altered in AD patients. However, there are no data regarding effects of AD treatment in this cholesterol pathway. Since a study from our group indicated a significant increase in membrane phospholipid metabolism by donepezil, the aim of this study was to evaluate the effect of short- and long-term donepezil treatment on cholesterol and metabolites 24OHC and 27OHC in plasma of AD patients and in healthy volunteers. At baseline, we found a decrease of 24OHC (p = 0.003) in AD patients. Cholesterol levels increased with donepezil treatment (p = 0.04) but no differences were observed regarding 24OHC and 27OHC. However, these results confirm and extend previous studies demonstrating disturbed cholesterol turnover in Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Colesterol/sangue , Inibidores da Colinesterase/uso terapêutico , Indanos/uso terapêutico , Oxisteróis/sangue , Piperidinas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Inibidores da Colinesterase/administração & dosagem , Donepezila , Feminino , Humanos , Indanos/administração & dosagem , Masculino , Piperidinas/administração & dosagem
5.
Front Physiol ; 8: 644, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28928671

RESUMO

Background: Oxysterols are bioactive lipids that control cellular cholesterol synthesis, uptake, and exportation besides mediating inflammation and cytotoxicity that modulate the development of atherosclerosis. Aerobic exercise training (AET) prevents and regresses atherosclerosis by the improvement of lipid metabolism, reverse cholesterol transport (RCT) and antioxidant defenses in the arterial wall. We investigated in dyslipidemic mice the role of a 6-week AET program in the content of plasma and aortic arch cholesterol and oxysterols, the expression of genes related to cholesterol flux and the effect of the exercise-mimetic AICAR, an AMPK activator, in macrophage oxysterols concentration. Methods: Sixteen-week old male apo E KO mice fed a chow diet were included in the protocol. Animals were trained in a treadmill running, 15 m/min, 5 days/week, for 60 min (T; n = 29). A control group was kept sedentary (S; n = 32). Plasma lipids and glucose were determined by enzymatic techniques and glucometer, respectively. Cholesterol and oxysterols in aortic arch and macrophages were measured by gas chromatography/mass spectrometry. The expression of genes involved in lipid metabolism was determined by RT-qPCR. The effect of AMPK in oxysterols metabolism was determined in J774 macrophages treated with 0.25 mM AICAR. Results: Body weight and plasma TC, TG, HDL-c, glucose, and oxysterols were similar between groups. As compared to S group, AET enhanced 7ß-hydroxycholesterol (70%) and reduced cholesterol (32%) in aorta. In addition, exercise increased Cyp27a1 (54%), Cd36 (75%), Cat (70%), Prkaa1 (40%), and Prkaa2 (51%) mRNA. In macrophages, the activation of AMPK followed by incubation with HDL2 increased Abca1 (52%) and Cd36 (220%) and decrease Prkaa1 (19%), Cyp27a1 (47%) and 7α-hydroxycholesterol level. Conclusion: AET increases 7ß-hydroxycholesterol in the aortic arch of dyslipidemic mice, which is related to the enhanced expression of Cd36. In addition, the increase and reduction of Cyp27a1 and Cyp7b1 in trained mice may contribute to enhance levels of 27-OH C. Both oxysterols may act as an alternative pathway for the RCT contributing to the reduction of cholesterol in the aortic arch preventing atherogenesis.

6.
Life Sci ; 153: 163-70, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-27074350

RESUMO

UNLABELLED: The mechanisms by which exercise affects atherosclerotic plaque stability remain incompletely understood. We evaluated the effects of two training protocols on both atherosclerotic plaque structure and the signaling pathways involved in plaque rupture. METHODS: Male low-density lipoprotein (LDL) receptor knockout mice were fed a high-fat, high-cholesterol diet (HFD). One group was subjected to moderate exercise using a treadmill for 14weeks (preventive protocol). The other group started an exercise regimen after 16weeks of the HFD (therapeutic group). Atherosclerotic plaques within the aorta were evaluated for lipid and collagen contents, as well as for inflammatory markers. Plasma cholesterol and cytokine levels were also determined. RESULTS: The mice receiving a HFD developed hypercholesterolemia and atherosclerotic plaques within the aorta. The aortas from the animals in the preventive protocol exhibited smaller lipid cores and higher collagen content. These animals also exhibited lower CD40 expression within the plaques. The aortas of the mice in the therapeutic group exhibited higher collagen content, but no differences in either lipid core size or plaque size were noted. No differences in blood pressure, plasma cholesterol, cytokine levels, plaque size or metalloproteinase 9 expression were observed in the trained animals compared with the sedentary animals. CONCLUSION: Moderate aerobic exercise modified atherosclerotic plaque characteristics and converted the plaques into a more stable phenotype, increasing the collagen content in response to both exercise programs. Furthermore, moderate aerobic exercise reduced the animals' fat content and decreased the activity of the CD40-CD40L signaling pathway in the preventive group.


Assuntos
Condicionamento Físico Animal , Placa Aterosclerótica/fisiopatologia , Animais , Masculino , Camundongos , Camundongos Knockout
7.
Clin Chim Acta ; 433: 169-73, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24657483

RESUMO

BACKGROUND: HDL is considered the most important mechanism for the excretion of intracellular cholesterol. The liver is the only organ capable to metabolize cholesterol into bile acid. The enzymatic conversion of cholesterol to bile acid is dependent on the cytochrome P450 microsomal system which is also responsible for the generation of oxysterols. The latter's plasma concentrations may reflect the metabolic processes of specific tissues where they are generated. The objective of this study was to investigate in healthy individuals who differ according to their HDL levels the concentration of oxysterols and relate it to the HDL-dependent cell cholesterol efflux rate. METHODS: 24-Hydroxycholesterol, 25-hydroxycholesterol, 27-hydroxycholesterol were determined in plasma by GLC/mass spectrometry in 107 healthy subjects with low HDL (HDL-C<1.03mmol/l) and high HDL cholesterol (HDL-C>1.55mmol/l). HDL-dependent in vitro cell cholesterol efflux rate was measured in 29 cases. RESULTS: No differences were found in plasma oxysterol concentrations between the Low HDL and High HDL groups. There was a significant negative correlation between HDL-C and 27-hydroxycholesterol. Plasma oxysterol concentrations were significantly lower in female than in male subjects. The Low HDL male group had higher 27-hydroxycholesterol than the High HDL male group. Cell cholesterol efflux rate was lower in Low HDL than in High HDL and related inversely with 27-hydroxycholesterol. CONCLUSION: As compared to High HDL, Low HDL men have increased 27-hydroxycholesterol plasma level that may circumvent their reduced cell cholesterol efflux rate.


Assuntos
HDL-Colesterol/sangue , Hidroxicolesteróis/sangue , Hidroxicolesteróis/metabolismo , Adulto , Transporte Biológico , HDL-Colesterol/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Fígado/citologia , Fígado/metabolismo , Masculino
8.
Atherosclerosis ; 231(2): 442-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24267264

RESUMO

SCOPE: There have been conflicting reports on the usefulness of phytosterols (PS) in preventing atherosclerosis. We evaluated the effects of dietary PS supplementation in LDLr-KO male mice on the plasma and aorta sterol concentrations and on atherosclerotic lesion development. METHODS AND RESULTS: Mice were fed a high fat diet (40% of energy) supplemented with or without PS (2% w/w, n = 10). Plasma and arterial wall cholesterol and PS concentrations, lesion area, macrophage infiltration, and mRNA expression from LOX-1, CD36, ABCA1 and ABCG1 in peritoneal macrophages were measured. After 16 weeks, the plasma cholesterol concentration in PS mice was lower than that in the controls (p = 0.02) and in the arterial wall (p = 0.03). Plasma PS concentrations were higher in PS-fed animals than in controls (p < 0.0001); however, the arterial wall PS concentration did not differ between groups. The atherosclerotic lesion area in the PS group (n = 5) was smaller than that in controls (p = 0.0062) and the macrophage area (p = 0.0007). PS correlates negatively with arterial lipid content and macrophage (r = -0.76; p < 0.05). PS supplementation induced lower ABCG1 mRNA expression (p < 0.05). CONCLUSIONS: Despite inducing an increase in PS plasma concentration, PS supplementation is not associated with its accumulation in the arterial wall and prevents atherosclerotic lesion development.


Assuntos
Artérias/patologia , Aterosclerose/prevenção & controle , Fitosteróis/química , Receptores de LDL/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Absorção , Animais , Aorta/patologia , Aterosclerose/patologia , Peso Corporal , Antígenos CD36/metabolismo , Colesterol/metabolismo , Comportamento Alimentar , Lipídeos/sangue , Lipoproteínas/metabolismo , Macrófagos/metabolismo , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fitosteróis/sangue , Receptores Depuradores Classe E/metabolismo
9.
Cardiovasc Diabetol ; 12: 173, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24267726

RESUMO

BACKGROUND: We have searched if plasma high density lipoprotein-cholesterol (HDL-C) concentration interferes simultaneously with whole-body cholesterol metabolism and insulin sensitivity in normal weight healthy adult subjects. METHODS: We have measured the activities of several plasma components that are critically influenced by insulin and that control lipoprotein metabolism in subjects with low and high HDL-C concentrations. These parameters included cholesteryl ester transfer protein (CETP), phospholipid transfer protein (PLTP), lecithin cholesterol acyl transferase (LCAT), post-heparin lipoprotein lipase (LPL), hepatic lipase (HL), pre-beta-1HDL, and plasma sterol markers of cholesterol synthesis and intestinal absorption. RESULTS: In the high-HDL-C group, we found lower plasma concentrations of triglycerides, alanine aminotransferase, insulin, HOMA-IR index, activities of LCAT and HL compared with the low HDL-C group; additionally, we found higher activity of LPL and pre-beta-1HDL concentration in the high-HDL-C group. There were no differences in the plasma CETP and PLTP activities. CONCLUSIONS: These findings indicate that in healthy hyperalphalipoproteinemia subjects, several parameters that control the metabolism of plasma cholesterol and lipoproteins are related to a higher degree of insulin sensitivity.


Assuntos
HDL-Colesterol/sangue , Resistência à Insulina , Insulina/sangue , Adulto , Idoso , Biomarcadores/sangue , Brasil , Proteínas de Transferência de Ésteres de Colesterol/sangue , Proteínas de Transferência de Ésteres de Colesterol/deficiência , VLDL-Colesterol/sangue , Feminino , Voluntários Saudáveis , Humanos , Peso Corporal Ideal , Absorção Intestinal , Lipase/sangue , Metabolismo dos Lipídeos , Erros Inatos do Metabolismo Lipídico/sangue , Lipase Lipoproteica/sangue , Masculino , Pessoa de Meia-Idade , Fosfatidilcolina-Esterol O-Aciltransferase/sangue , Proteínas de Transferência de Fosfolipídeos/sangue , Adulto Jovem
10.
Chronobiol Int ; 30(8): 1011-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23837747

RESUMO

Assessment of lipid profile parameters has been considered a cornerstone in classifying individuals and populations at risk for cardiovascular disease. Recently, however, preliminary data have raised the possibility of seasonal variations in these parameters, which may cause under- or overestimation. Biological rhythms and seasonal variation of lipid profile was investigated in 227 359 consecutive individuals who underwent health checkups in primary care centers between 2008 and 2010. Plasma low-density lipoprotein cholesterol (LDL-C) >130 mg/dL was 8% more prevalent during winter than summer, with a larger difference among women and middle-aged adults (p < 0.001). High-density lipoprotein cholesterol (HDL-C) <40 mg/dL and triglycerides (TG) >150 mg/dL were respectively 9% and 5% more prevalent during the summer (p < 0.001). Variation amplitude was 3.4 ± 0.3 mg/dL for HDL-C (p = 0.005), 7 ± 2 mg/dL for LDL-C (p = 0.047), and 12 ± 9 mg/dL for TG (p = 0.058). Based on a large population sample, this study confirms the existence of biological rhythms and seasonal variation in lipid profile. This finding must be particularly accounted for in cross-sectional analyses of relative risk, prevalence, or the rate of goal achievement for lipid parameters.


Assuntos
Dislipidemias/epidemiologia , Periodicidade , Estações do Ano , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Brasil/epidemiologia , Criança , Pré-Escolar , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Dislipidemias/sangue , Dislipidemias/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Prevalência , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Fatores de Tempo , Triglicerídeos/sangue , Adulto Jovem
11.
Clin Biochem ; 46(15): 1619-21, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23850851

RESUMO

UNLABELLED: Sterol 27-hydroxylase converts cholesterol to 27-hydroxycholesterol (27-OHC) which is widely distributed among tissues and is expressed at high levels in the vascular endothelium and macrophages. There is a continuous flow of this oxysterol from the tissues into the liver, where it is converted to bile acids. OBJECTIVE: Measure plasma concentrations of 27-OHC in subjects that differ according to their plasma HDL-C concentration. METHODS: Healthy men presenting low HDL-C (<1.03 mmol/L), n=18 or high HDL-C (>1.55 mmol/L), n=18, BMI<30 kg/m² were recruited after excluding secondary causes that might interfere with their plasma lipid concentrations such as smoking, heavy drinking and diabetes. Blood samples were drawn after a 12h fasting period for the measurement of 27-OHC by the combined GC/MS analysis utilizing deuterium-label internal standards. RESULTS: The plasma ratio 27-OHC/total cholesterol (median and range nmoL/mmoL) was 50.41 (27.47-116.00) in the High HDL-C subjects and 63.34 (36.46-91.18) in the Low HDL-C subjects (p=0.0258). CONCLUSION: Our data indicate that the production of 27-OHC by extrahepatic tissues and its transport to the liver may represent an alternative pathway for a deficient reverse cholesterol transport system when plasma HDL-C is low.


Assuntos
HDL-Colesterol/sangue , Hidroxicolesteróis/sangue , Fígado/metabolismo , Adulto , Idoso , Transporte Biológico , Jejum , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade
12.
Atherosclerosis ; 224(1): 66-74, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22809447

RESUMO

The development of atherosclerosis and the inflammatory response were investigated in LDLr-KO mice on three high-fat diets (40% energy as fat) for 16 weeks: trans (TRANS), saturated (SAFA) or ω-6 polyunsaturated (PUFA) fats. The following parameters were measured: plasma lipids, aortic root total cholesterol (TC), lesion area (Oil Red-O), ABCA1 content and macrophage infiltration (immunohistochemistry), collagen content (Picrosirius-red) and co-localization of ABCA1 and macrophage (confocal microscopy) besides the plasma inflammatory markers (IL-6, TNF-α) and the macrophage inflammatory response to lipopolysaccharide from Escherichia coli (LPS). As expected, plasma TC and TG concentrations were lower on the PUFA diet than on TRANS or SAFA diets. Aortic intima macrophage infiltration, ABCA1 content, and lesion area on PUFA group were lower compared to TRANS and SAFA groups. Macrophages and ABCA1 markers did not co-localize in the atherosclerotic plaque, suggesting that different cell types were responsible for the ABCA1 expression in plaques. Compared to PUFA, TRANS and SAFA presented higher collagen content and necrotic cores in atherosclerotic plaques. In the artery wall, TC was lower on PUFA compared to TRANS group; free cholesterol was lower on PUFA compared to TRANS and SAFA; cholesteryl ester concentration did not vary amongst the groups. Plasma TNF-α concentration on PUFA and TRANS-fed mice was higher compared to SAFA. No difference was observed in IL-6 concentration amongst groups. Regarding the macrophage inflammatory response to LPS, TRANS and PUFA presented higher culture medium concentrations of IL-6 and TNF-α as compared to SAFA. The PUFA group showed the lowest amount of the anti-inflammatory marker IL-10 compared to TRANS and SAFA groups. In conclusion, PUFA intake prevented atherogenesis, even in a pro-inflammatory condition.


Assuntos
Aterosclerose/prevenção & controle , Ácidos Graxos Ômega-6/uso terapêutico , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Animais , Aorta/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Colesterol/sangue , Colágeno/metabolismo , Dieta Hiperlipídica , Gorduras Insaturadas na Dieta/metabolismo , Gorduras Insaturadas na Dieta/uso terapêutico , Inflamação/metabolismo , Inflamação/prevenção & controle , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Receptores de LDL/deficiência , Ácidos Graxos trans/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Lipids Health Dis ; 10: 172, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21957962

RESUMO

BACKGROUND: Advanced glycation end products (AGE) alter lipid metabolism and reduce the macrophage expression of ABCA-1 and ABCG-1 which impairs the reverse cholesterol transport, a system that drives cholesterol from arterial wall macrophages to the liver, allowing its excretion into the bile and feces. Oxysterols favors lipid homeostasis in macrophages and drive the reverse cholesterol transport, although the accumulation of 7-ketocholesterol, 7alpha- hydroxycholesterol and 7beta- hydroxycholesterol is related to atherogenesis and cell death. We evaluated the effect of glycolaldehyde treatment (GAD; oxoaldehyde that induces a fast formation of intracellular AGE) in macrophages overloaded with oxidized LDL and incubated with HDL alone or HDL plus LXR agonist (T0901317) in: 1) the intracellular content of oxysterols and total sterols and 2) the contents of ABCA-1 and ABCG-1. METHODS: Total cholesterol and oxysterol subspecies were determined by gas chromatography/mass spectrometry and HDL receptors content by immunoblot. RESULTS: In control macrophages (C), incubation with HDL or HDL + T0901317 reduced the intracellular content of total sterols (total cholesterol + oxysterols), cholesterol and 7-ketocholesterol, which was not observed in GAD macrophages. In all experimental conditions no changes were found in the intracellular content of other oxysterol subspecies comparing C and GAD macrophages. GAD macrophages presented a 45% reduction in ABCA-1 protein level as compared to C cells, even after the addition of HDL or HDL + T0901317. The content of ABCG-1 was 36.6% reduced in GAD macrophages in the presence of HDL as compared to C macrophages. CONCLUSION: In macrophages overloaded with oxidized LDL, glycolaldehyde treatment reduces the HDL-mediated cholesterol and 7-ketocholesterol efflux which is ascribed to the reduction in ABCA-1 and ABCG-1 protein level. This may contribute to atherosclerosis in diabetes mellitus.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Regulação para Baixo , Produtos Finais de Glicação Avançada/metabolismo , Cetocolesteróis/metabolismo , Lipoproteínas/metabolismo , Macrófagos/metabolismo , Esteróis/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Acetaldeído/análogos & derivados , Acetaldeído/farmacologia , Animais , Anticolesterolemiantes/farmacologia , Linhagem Celular , Angiopatias Diabéticas/imunologia , Angiopatias Diabéticas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Receptores X do Fígado , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Receptores Nucleares Órfãos/agonistas , Oxidantes/farmacologia , Estresse Oxidativo
14.
J Nutr ; 140(6): 1127-32, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20357081

RESUMO

We investigated the effects of dietary trans fatty acids, PUFA, and SFA on body and liver fat content, liver histology, and mRNA of enzymes involved in fatty acid metabolism. LDL receptor knockout weaning male mice were fed for 16 wk with diets containing 40% energy as either trans fatty acids (TRANS), PUFA, or SFA. Afterwards, subcutaneous and epididymal fat were weighed and histological markers of nonalcoholic fatty liver disease (NAFLD) were assessed according to the Histological Scoring System for NAFLD. PPARalpha, PPARgamma, microsomal triglyceride transfer protein (MTP), carnitine palmitoyl transferase 1 (CPT-1), and sterol regulatory element binding protein-1c (SREBP-1c) mRNA were measured by quantitative RT-PCR. Food intake was similar in the 3 groups, although mice fed the TRANS diet gained less weight than those receiving the PUFA diet. Compared with the PUFA- and SFA-fed mice, TRANS-fed mice had greater plasma total cholesterol (TC) and triglyceride (TG) concentrations, less epididymal and subcutaneous fat, larger livers with nonalcoholic steatohepatitis (NASH)-like lesions, and greater liver TC and TG concentrations. Macrosteatosis in TRANS-fed mice was associated with a higher homeostasis model assessment of insulin resistance (HOMA(IR)) index and upregulated mRNA related to hepatic fatty acid synthesis (SREBP-1c and PPARgamma) and to downregulated MTP mRNA. Diet consumption did not alter hepatic mRNA related to fatty acid oxidation (PPARalpha and CPT-1). In conclusion, compared with PUFA- and SFA-fed mice, TRANS-fed mice had less adiposity, impaired glucose tolerance characterized by greater HOMA(IR) index, and NASH-like lesions due to greater hepatic lipogenesis. These results demonstrate the role of trans fatty acid intake on the development of key features of metabolic syndrome.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Fígado Gorduroso/induzido quimicamente , Ácidos Graxos trans/toxicidade , Animais , Glicemia/efeitos dos fármacos , Ácidos Graxos/toxicidade , Ácidos Graxos Insaturados/toxicidade , Insulina/sangue , Lipoproteínas , Masculino , Síndrome Metabólica , Camundongos , Camundongos Knockout , Receptores de LDL/genética , Receptores de LDL/metabolismo
15.
J Agric Food Chem ; 57(5): 1775-80, 2009 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-19219987

RESUMO

The antioxidant activity of mate tea, the roasted product derived from yerba mate (Ilex paraguarienis), was observed in vitro and in animal models, but studies in humans are lacking. The aim of this study was to investigate the effects of mate tea supplementation on plasma susceptibility to oxidation and on antioxidant enzyme gene expression in healthy nonsmoking women, after acute or prolonged ingestion. We evaluated plasma total antioxidant status (TAS), the kinetics of diene conjugate generation, and thiobarbituric acid reactive substance (TBARS) contents in plasma, as well as mRNA levels of antioxidant gluthatione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). After the supplementation period with mate tea, lipid peroxidation was acutely lowered, an effect that was maintained after prolonged administration. Total antioxidant status and the level of antioxidant enzyme gene expression were also demonstrated after prolonged consumption. These results suggest that regular consumption of mate tea may increase antioxidant defense of the body by multiple mechanisms.


Assuntos
Antioxidantes/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/genética , Ilex paraguariensis/química , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Superóxido Dismutase/genética , Adulto , Ingestão de Alimentos , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Saúde da Mulher , Adulto Jovem
16.
Med Sci Sports Exerc ; 40(5): 779-86, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18408623

RESUMO

PURPOSE: In this study we analyzed the role played by aerobic exercise training in the plasma lipoprotein profile, prebeta 1-HDL concentration, and in the in vitro HDL3 ability to remove cholesterol from macrophages and inhibit LDL oxidation in type 2 diabetes mellitus (DM) patients and control subjects, in the fasting and postprandial states. METHODS: Healthy controls (HTC, N = 11; 1 M/10 F) and subjects with type 2 diabetes mellitus (DMT, N = 11; 3M/8F) were engaged in a 4-month aerobic training program, and compared with a group of sedentary subjects with type 2 diabetes mellitus (DMS, N = 10; 4 M/6 F). All groups were submitted to an oral fat load test to analyze all parameters, both at the beginning of the investigation protocol (basal) and at the end of the study period (final). RESULTS: Exercising did not modify body weight, BMI, plasma concentrations of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides (TG), glucose, insulin, or HOMA-IR, but it reduced the waist circumference. The HDL3 composition did not change, and its ability to remove cell cholesterol was unaltered by aerobic training. In DMT but not in HTC, aerobic training improved 15% the HDL3 protective effect against LDL maximal oxidation rate in the fasting state, and reduced 24% the plasma prebeta 1-HDL concentration in the postprandial state, suggesting an enhanced prebeta 1-HDL conversion into larger, more mature HDL particles. In this regard, regular aerobic exercise enriched HDL2 with TG in the fasting and postprandial states in HTC and in the fasting phase in DMT. CONCLUSION: Our results show that aerobic exercise training in diabetes mellitus improves the HDL efficiency against LDL oxidation and favors HDL maturation. These findings were independent of changes in insulin resistance and of the rise of plasma HDL cholesterol concentration.


Assuntos
HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Exercício Físico , Análise de Variância , Antropometria , Estudos de Casos e Controles , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial
17.
Atherosclerosis ; 200(2): 410-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18262533

RESUMO

BACKGROUND: Dietary salt restriction has been reported to adversely modify the plasma lipoprotein profile in hypertensive and in normotensive subjects. We investigated the effects of the low sodium intake (LSI) on the plasma lipoprotein profile and on inflammation and thrombosis biomarkers during the fasting and postprandial periods. METHODS: Non-obese, non-treated hypertensive adults (n=41) were fed strictly controlled diets. An initial week on a control diet (CD, Na=160 mmol/day) was followed by 3 weeks on LSI (Na=60 mmol/day). At admission and on the last day of each period, the 24-h ambulatory blood pressure was monitored and blood was drawn after an overnight fasting period and after a fat-rich test meal. RESULTS: The dietary adherence was confirmed by 24-h urinary sodium excretion. Fasting triglyceride (TG), chylomicron-cholesterol, hsC-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) concentrations, renin activity, aldosterone, insulin, and homeostasis model assessment insulin resistance (HOMA-IR) values were higher, but non-esterified fatty acids (NEFA) were lower on LSI than on CD. For LSI, areas under the curve (AUC) of TG, chylomicron-cholesterol, apoB and the cholesterol/apoB ratio were increased, whereas AUC-NEFA was lowered. LSI did not modify body weight, hematocrit, fasting plasma cholesterol, glucose, adiponectin, leptin, fibrinogen and factor VII (FVII), and AUC of lipoprotein lipase and of lipoprotein remnants. CONCLUSION: LSI induced alterations in the plasma lipoproteins and in inflammatory markers that are common features of the metabolic syndrome.


Assuntos
Dieta , Hipertensão/sangue , Inflamação/sangue , Lipoproteínas/sangue , Cloreto de Sódio na Dieta/metabolismo , Adulto , Aterosclerose/sangue , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Placebos , Período Pós-Prandial , Trombose/sangue
18.
Am J Clin Nutr ; 86(5): 1270-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17991635

RESUMO

BACKGROUND: Plasma HDL concentrations and composition, important predictors of coronary heart disease, are modified by fatty acids (FAs) in high-fat diets. OBJECTIVE: Following the National Cholesterol Education Program Adult Treatment Panel III recommendation that 25%-30% of total calorie intake be in the form of fat, we compared the results of the intake of 30% of energy as fat in diets enriched with trans, polyunsaturated, or saturated FAs. These dietary effects on the composition and ability of HDL(2), HDL(3), and total plasma to efflux cholesterol from mouse peritoneal macrophages that previously were loaded with LDL-acetylated 14C-cholesteryl ester were evaluated by using ultracentrifugally isolated lipoproteins. DESIGN: After a 2-wk run-in period, 30 healthy persons (9 M, 21 F), were randomly distributed among 3 groups (n = 10/group) and fed for 4 wk with either an 8.3% trans FA, a 14.6% polyunsaturated FA, or a 13.2% saturated FA diet. The 3 diets had similar proportions of monounsaturated FAs. RESULTS: The percentage of radioactive cell cholesterol removal did not vary among these diets, possibly because of the small difference in the composition of the HDL fraction elicited by the different diets. However, the percentage was consistently higher for HDL(3) than for HDL(2). CONCLUSION: Differences in the cell cholesterol efflux with these diets were not observed, probably because the changes in the HDL composition were quite modest as a result of the limitation of the fat intake to 30% of total calories and because of the rigorous control of the proportions of FAs in the experimental diets used in this investigation.


Assuntos
HDL-Colesterol/sangue , Colesterol/metabolismo , Gorduras na Dieta/administração & dosagem , Ácidos Graxos/administração & dosagem , Macrófagos/metabolismo , Adulto , Animais , Transporte Biológico , Células Cultivadas , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade
19.
Int J Psychoanal ; 87(Pt 6): 1587-601, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17130084

RESUMO

The author describes a type of mental development in which the primitive libidinal value of faeces and urine is kept unaltered all through adulthood. In this instance, individuals harbour fantasies of projective identification with the internal parents, denying their real dependence, which leads to a pseudomaturity. These fantasies are usually accompanied by anal and genital masturbation and have intense aggressive content. Furthermore, there is a significant confusion among all body orifices, leading to an inability to distinguish the self from the object, the inner world from outside reality. Individuals with this type of development can only maintain limited object relations and have highly erotized excretory activities. Manipulation of faeces may occur. This structure works as a defence against breakdown, but may also provide pleasure as it gives the illusion of omnipotent control of the object, as typical in pathological organizations. The author presents clinical material and discusses the difficulties of the analysis, in which the patient tries to seduce the analyst into colluding with his mental functioning, primarily as a means of communication as well as a projection of his despair and his disbelief in the analyst's ability to help him.


Assuntos
Confusão/psicologia , Confusão/terapia , Libido , Interpretação Psicanalítica , Terapia Psicanalítica/métodos , Adulto , Contratransferência , Fezes , Humanos , Masculino , Masturbação , Urina
20.
Lipids ; 41(7): 655-62, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17069349

RESUMO

The possibility that soy protein containing isoflavones influences the development of experimental atherosclerosis has been investigated in ovariectomized mice heterozygous for the human CETP transgene and for the LDL-receptor null allele (LDLr(+/-) CETP(+/-)). After ovariectomy at 8 wk of age they were fed a fat/cholesterol-rich diet for 19 wk and divided into three experimental groups: dietary unmodified soy protein containing isoflavones (mg/g of diet), either at low-dose (Iso Low, 0.272, n = 25), or at high-dose (Iso High, 0.535, n = 28); and the atherogenic diet containing an isoflavone-depleted alcohol-washed soy protein as a control group (n = 28). Aortic root lipid-stained lesion area (mean microm2 x 10(3) +/- SD) did not differ among Iso Low (12.3 +/- 9.9), Iso High (7.4 +/- 6.4), and controls (10.7 +/- 12.8). Autoantibody titers against plasma oxidized LDL did not differ among the experimental groups. Using the control mice as the reference value (100%), in vitro mouse peritoneal macrophage uptake of labeled acetylated LDL-cholesterol was lower in the Iso High (68%) than in the Iso Low (85%) group. The in vitro percent removal by exogenous HDL of labeled unesterified cholesterol from macrophages previously enriched with human [4- 14C]-cholesteryl oleate acetylated LDL was enhanced in the Iso High group (50%). In spite of these in vitro potentially antiatherogenic actions, soy protein containing isoflavones did not modify the average size of lipid-stained area in the aortic root.


Assuntos
Aterosclerose/metabolismo , Proteínas de Transporte/genética , Glicoproteínas/genética , Isoflavonas/farmacologia , Lipoproteínas/metabolismo , Macrófagos/metabolismo , Proteínas de Soja/farmacologia , Animais , Aterosclerose/dietoterapia , Aterosclerose/genética , Proteínas de Transporte/metabolismo , Proteínas de Transferência de Ésteres de Colesterol , Modelos Animais de Doenças , Progressão da Doença , Feminino , Glicoproteínas/metabolismo , Heterozigoto , Humanos , Lipídeos/sangue , Lipoproteínas/sangue , Macrófagos/química , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovariectomia , Receptores de LDL/genética , Proteínas de Soja/química , Transgenes
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