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1.
Ann Dermatol Venereol ; 151(3): 103289, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39002406

RESUMO

AIMS: To describe the demographic characteristics of heroin and cocaine injectors with chronic injection-related trophic disorders, as well as the clinical and progressive characteristics of these disorders. METHODS: A descriptive, observational, multicenter and retrospective study over the last 15 years. Patients were recruited via a call for cases and by consulting the health data warehouse of the university hospital center. RESULTS: The population comprised 39 injection drug users, of whom 79.5% were male, with a median age of 41 years. Subjects had numerous co-addictions and 70.5% were infected with hepatitis C virus. Trophic disorders were multiple in some cases: 43.5% of patients had lymphoedema, 87% had ulcers, and 56.5% had injection-related scars. Ulcers were multiple, large, and present for a median of 3 years. They were located on the upper limbs in 32.5% of cases. Ulcers constituted a source of complications in 64.5% of cases and these were infectious in 91% of cases (local, osteoarticular or systemic). During follow-up, 8 patients died and 21.5% of patients requiring ulcer care were lost to follow-up. CONCLUSIONS: This study showed a high rate of complications, particularly infections, of ulcers in injection drug users. Localization of these ulcers to the upper limbs, although rare in the general population, is relatively frequent in this population. Follow-up is difficult and cooperation between dermatologist and addictologist is essential to improve patient care.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Dependência de Heroína , Úlcera Cutânea , Abuso de Substâncias por Via Intravenosa , Humanos , Masculino , Estudos Retrospectivos , Feminino , Adulto , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Dependência de Heroína/complicações , Dependência de Heroína/epidemiologia , Transtornos Relacionados ao Uso de Cocaína/complicações , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Úlcera Cutânea/epidemiologia , Úlcera Cutânea/etiologia , Pessoa de Meia-Idade , Doença Crônica , Cicatriz/etiologia
2.
J Eur Acad Dermatol Venereol ; 36(12): 2423-2429, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35854650

RESUMO

BACKGROUND: Dupilumab is the first biotherapy available for the treatment of moderate-to-severe childhood atopic dermatitis (AD). OBJECTIVE: The aim of this study was to evaluate the effectiveness and safety of dupilumab in daily practice. METHODS: Patients aged 6-11, who had received a first dose of dupilumab, were included in this multicentre retrospective cohort study. The primary endpoint was change in SCORAD after 3 months of treatment. Secondary endpoints were change in IGA score at 3 months, proportion of patients with SCORAD50 and SCORAD75, description of adverse events and proportion of children in our cohort who would be excluded from pivotal phase 3 clinical trial. RESULTS: Eighty patients were included. After 3 months of treatment, there was a significant decrease in SCORAD (mean: 21.8 ± 13.8 vs 53.9 ± 18.5; P < 0.0001) and IGA (1.3 ± 0.8 vs 3.5 ± 0.7; P < 0.0001). Conjunctivitis was observed in 11.3% (n = 9/80); three patients experienced dupilumab facial redness (DFR); 17.5% (n = 14/80) reported injection site reactions; 6.3% (n = 5/80) discontinued treatment. 61.2% (n = 49/80) children were ineligible in the phase 3 trial. LIMITATIONS: There is no control group. Because it was a real life study based on information from patient medical records in a French multicentre cohort, we cannot rule out the presence of reporting bias generated by the use of patient reported characteristics and missing information. CONCLUSION: These real-life data confirm the efficacy and safety of dupilumab in children with moderate to severe AD extended to dyshidrosis and atopic prurigo, but it also revealed a lower frequency of DFR and conjunctivitis. However, administration in injectable form may be a barrier in this age group.


Assuntos
Conjuntivite , Dermatite Atópica , Criança , Humanos , Dermatite Atópica/tratamento farmacológico , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Conjuntivite/induzido quimicamente , Estudos de Coortes , Imunoglobulina A
4.
Circ Res ; 85(8): e17-24, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10521249

RESUMO

The potential role of anti-inflammatory cytokines in the modulation of the atherosclerotic process remains unknown. Interleukin (IL)-10 has potent deactivating properties in macrophages and T cells and modulates many cellular processes that may interfere with the development and stability of the atherosclerotic plaque. IL-10 is expressed in human atherosclerosis and is associated with decreased signs of inflammation. In the present study, we show that IL-10-deficient C57BL/6J mice fed an atherogenic diet and raised under specific pathogen-free conditions exhibit a significant 3-fold increase in lipid accumulation compared with wild-type mice. Interestingly, the susceptibility of IL-10-deficient mice to atherosclerosis was exceedingly high (30-fold increase) when the mice were housed under conventional conditions. Atherosclerotic lesions of IL-10-deficient mice showed increased T-cell infiltration, abundant interferon-gamma expression, and decreased collagen content. In vivo, transfer of murine IL-10 achieved 60% reduction in lesion size. These results underscore the critical roles of IL-10 in both atherosclerotic lesion formation and stability. Moreover, IL-10 appears to be crucial as a protective factor against the effect of environmental pathogens on atherosclerosis.


Assuntos
Arteriosclerose/imunologia , Interleucina-10/deficiência , Animais , Arteriosclerose/patologia , Arteriosclerose/terapia , Colesterol/sangue , Dieta Aterogênica , Feminino , Interleucina-10/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL
5.
Biochim Biophys Acta ; 1255(1): 31-8, 1995 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-7893735

RESUMO

High-density lipoprotein (HDL) and two lipoprotein particles, those containing apo A-I and apo A-II (LpA-I:A-II) and those containing only apo A-I (LpA-I) were examined for their effect on Cu(2+)-catalyzed oxidation of human low-density lipoprotein (LDL). Lipoproteins and lipoprotein particles were prepared from plasma samples of five healthy subjects. LDL and HDL were purified by ultracentrifugation, LpA-I and LpA-I:A-II were isolated by an immunoaffinity chromatography procedure. The contaminating albumin often linked to the LpA-I affinity purified particles was eliminated by selected affinity immunosorption. The presence of HDL, LpA-I or LpA-I:A-II, at an apo A-I-containing lipoproteins/LDL ratio of 1, did not prevent LDL oxidation when assessed by oxidation kinetics, electrophoretic mobility, amounts of thiobarbituric acid-reactive products and fragmentation of apo B-100. On the other hand, when the albumin removing step was omitted, the subfraction of albumin-containing LpA-I particles impeded and even inhibited the oxidation of LDL in an albumin dose-dependent manner.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteína(a)/análogos & derivados , Lipoproteínas LDL/metabolismo , Albumina Sérica/farmacologia , Cobre/farmacologia , Relação Dose-Resposta a Droga , Humanos , Lipoproteína(a)/química , Lipoproteína(a)/isolamento & purificação , Lipoproteína(a)/farmacologia , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/química , Lipoproteínas LDL/isolamento & purificação , Albumina Sérica/química , Espectrofotometria Ultravioleta
6.
Circulation ; 99(18): 2445-51, 1999 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-10318668

RESUMO

BACKGROUND: In humans, fibrates are frequently used normolipidemic drugs. Fibrates act by regulating genes involved in lipoprotein metabolism via activation of the peroxisome proliferator-activated receptor-alpha (PPARalpha) in liver. In rodents, however, fibrates induce a peroxisome proliferation, leading to hepatomegaly and possibly hepatocarcinogenesis. Although this peroxisome proliferative response appears not to occur in humans, it remains controversial whether the beneficial effects of fibrates on lipoprotein metabolism can occur dissociated from such undesirable peroxisomal response. Here, we assessed the influence of fenofibrate on lipoprotein metabolism and peroxisome proliferation in the rabbit, an animal that, contrary to rodents and similar to humans, is less sensitive to peroxisome proliferators. METHODS AND RESULTS: First, we demonstrate that in normal rabbits, fenofibrate given at a high dose for 2 weeks does not influence serum concentrations or intestinal mRNA levels of the HDL apolipoprotein apoA-I. Therefore, the study was continued with human apoA-I transgenic rabbits that overexpress the human apoA-I gene under control of its homologous promoter, including its PPAR-response elements. In these animals, fenofibrate increases serum human apoA-I concentrations via an increased expression of the human apoA-I gene in liver. Interestingly, liver weight or mRNA levels and activity of fatty acyl-CoA oxidase, a rate-limiting and marker enzyme of peroxisomal beta-oxidation, remain unchanged after fenofibrate. CONCLUSIONS: Expression of the human apoA-I transgene in rabbit liver suffices to confer fibrate-mediated induction of serum apoA-I. Furthermore, these data provide in vivo evidence that the beneficial effects of fibrates on lipoprotein metabolism occur mechanistically dissociated from any deleterious activity on peroxisome proliferation and possibly hepatocarcinogenesis.


Assuntos
Anticolesterolemiantes/uso terapêutico , Apolipoproteína A-I/metabolismo , Fenofibrato/uso terapêutico , Microcorpos/efeitos dos fármacos , Proliferadores de Peroxissomos/farmacologia , Coelhos/metabolismo , Acil-CoA Oxidase , Animais , Animais Geneticamente Modificados , Anticolesterolemiantes/farmacologia , Apolipoproteína A-I/genética , HDL-Colesterol/sangue , Resistência a Medicamentos , Fenofibrato/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Lipase Lipoproteica/metabolismo , Lipoproteínas HDL/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Tamanho do Órgão/efeitos dos fármacos , Especificidade de Órgãos , Oxirredutases/análise , Proliferadores de Peroxissomos/toxicidade , Proteínas Recombinantes de Fusão/metabolismo , Roedores/metabolismo , Especificidade da Espécie
7.
Diabetes ; 41 Suppl 2: 81-5, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1526342

RESUMO

Lipoprotein particles containing apoA-I but not apoA-II are, among high-density lipoproteins, effective protectors against atherosclerosis that act by promoting the efflux of cellular cholesterol and the reverse cholesterol transport process. Because previous studies showed that in vitro nonenzymatic glycosylation of HDL impairs HDL receptor-mediated cholesterol efflux, we isolated Lp A-I from two poorly controlled insulin-dependent diabetic patients and compared the chemical composition and ability to promote cholesterol efflux with the same particles purified from two matched nondiabetic control subjects. No differences in lipid composition or in the ability to promote cholesterol efflux from cultured adipose cells were noted between the two types of Lp A-I preparations. However, when we separated Lp A-I from diabetic subjects by degree of glycosylation, the specifically glycosylated subfractions were about 50% less effective in producing cholesterol efflux than the nonglycosylated particles.


Assuntos
Apolipoproteína A-I/metabolismo , Colesterol/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Adulto , Animais , Transporte Biológico , Linhagem Celular , Glicosilação , Humanos , Masculino , Camundongos
8.
Arterioscler Thromb Vasc Biol ; 20(11): 2453-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11073852

RESUMO

Studies performed in vivo have been controversial regarding the implication of human apolipoprotein (apo)A-II in the atherogenic process. Expression of human apoA-II in transgenic mice fed a chow diet leads to (1) a bimodal distribution of high density lipoprotein (HDL) size as in humans, (2) a reduction in total cholesterol concentration that is mainly due to a reduction in non-HDL cholesterol level, and (3) a dramatic reduction in mouse endogenous apoA-I and apoA-II. After 20 weeks on an atherogenic diet, transgenic mice had reduced total cholesterol concentrations because of a reduction in cholesterol associated with all lipoprotein classes. Endogenous apoA-I and apoA-II were also dramatically decreased in transgenic mice. The mean area of atherosclerotic lesions was drastically decreased in transgenic mice (-44%, P=0.0027) compared with control mice. The amount of aortic surface covered by lesions was positively correlated with very low density lipoprotein cholesterol (P<0.01) and intermediate density lipoprotein cholesterol levels (P<0.05). Transgenic mice were protected against the development of atherosclerosis despite a marked decrease in HDL cholesterol and apoA-I concentrations. This protection may be related to the marked reduction in circulating low density lipoprotein (very low density and intermediate density lipoprotein) levels in transgenic mice.


Assuntos
Apolipoproteína A-II/genética , Arteriosclerose/genética , Arteriosclerose/prevenção & controle , Dieta Aterogênica , Fenômenos Fisiológicos da Nutrição Animal , Animais , Apolipoproteína A-II/sangue , Apolipoproteínas/sangue , Arteriosclerose/enzimologia , Arteriosclerose/patologia , Transporte Biológico/genética , Colesterol/metabolismo , HDL-Colesterol/sangue , HDL-Colesterol/química , Feminino , Predisposição Genética para Doença , Humanos , Lipídeos/sangue , Lipase Lipoproteica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Albumina Sérica
9.
Endocrinology ; 141(1): 462-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10614672

RESUMO

Estradiol significantly decreases fatty streak formation in the aortic root of chow-fed apolipoprotein E-deficient mice. In contrast, immunodeficient mice with homozygous disruption at the recombinase activating gene 2 loci present fatty streak development that is insensitive to estradiol. Lymphocytes thus appear to be required for development of the atheroprotective effect of estradiol in this mouse model.


Assuntos
Apolipoproteínas E/genética , Arteriosclerose/tratamento farmacológico , Estradiol/uso terapêutico , Animais , Aorta/patologia , Apolipoproteínas E/imunologia , Arteriosclerose/genética , Arteriosclerose/imunologia , Arteriosclerose/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Transposases/genética , Transposases/metabolismo
10.
Gene ; 156(2): 199-205, 1995 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-7758957

RESUMO

The human antithrombin III-encoding gene (hAT-III) promoter (phAT-III) was used to generate transgenic mice producing a human hepatic apolipoprotein, apolipoprotein A-II (hApoA-II). Integration of the transgene into the mouse genome resulted in the efficient production of hApoA-II in plasma, reaching up to 0.40 g/l in two transgenic lines. The human ApoA-II mRNA was detected at high levels, both in the liver and in the kidney of transgenic mice. The rat AT-III gene shows the same expression pattern. In contrast, as previously described, the same promoter permitted the expression of the SV40 large T antigen only in the liver of transgenic mice. In view of the extra-hepatic distribution of the ApoA-II mRNA, a preliminary characterization of the hAT-III proximal promoter (phAT-III), driving the expression of the transgene, was realized. Using DNase I footprinting analysis with liver nuclear extracts, four protected regions (I-IV) were identified in the first 175 bp of the 5' region of hAT-III. Electrophoretic mobility shift assays performed with liver and kidney nuclear extracts indicate that region III (nucleotides (nt) -67 to -90) interacts with the liver-enriched HNF4 nuclear factor. Furthermore, our data suggest that region I (nt -123 to -138) interacts with the liver-enriched HNF3 transcription factor family, both in liver and kidney. Taken together, these results demonstrate that phAT-III is a useful tool to create transgenic mice producing high plasma levels of a human apolipoprotein due to expression of the transgene in liver and kidney.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Antitrombina III/genética , Apolipoproteína A-II/biossíntese , Apolipoproteína A-II/genética , Marcação de Genes/métodos , Regiões Promotoras Genéticas/genética , Animais , Apolipoproteína A-II/sangue , Sequência de Bases , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Dados de Sequência Molecular , RNA Mensageiro/análise , Proteínas Recombinantes de Fusão/biossíntese , Distribuição Tecidual , Fatores de Transcrição/metabolismo
11.
FEBS Lett ; 452(3): 160-4, 1999 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-10386582

RESUMO

Statins are hypolipidemic drugs which not only improve cholesterol but also triglyceride levels. Whereas their cholesterol-reducing effect involves inhibition of de novo biosynthesis of cellular cholesterol through competitive inhibition of its rate-limiting enzyme 3-hydroxy-3-methylglutaryl CoA reductase, the mechanism by which they lower triglycerides remains unknown and forms the subject of the current study. Treatment of normal rats for 4 days with simvastatin decreased serum triglycerides significantly, whereas it increased high density lipoprotein cholesterol moderately. The decrease in triglyceride concentrations after simvastatin was caused by a reduction in the amount of very low density lipoprotein particles which were of an unchanged lipid composition. Simvastatin administration increased the lipoprotein lipase mRNA and activity in adipose tissue and heart. This effect on lipoprotein lipase was accompanied by decreased mRNA as well as plasma levels of the lipoprotein lipase inhibitor apolipoprotein C-III. These results suggest that the triglyceride-lowering effect of statins involves a stimulation of lipoprotein lipase-mediated clearance of triglyceride-rich lipoproteins.


Assuntos
Apolipoproteínas C/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lipase Lipoproteica/sangue , Sinvastatina/farmacologia , Triglicerídeos/sangue , Animais , Apolipoproteína A-I/sangue , Apolipoproteína A-II/sangue , Apolipoproteína C-III , Apolipoproteínas C/efeitos dos fármacos , Colesterol/sangue , HDL-Colesterol/sangue , Lipase Lipoproteica/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
12.
FEBS Lett ; 473(3): 333-6, 2000 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-10818235

RESUMO

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors, which heterodimerize with the retinoid X receptor and bind to peroxisome proliferator response elements in the promoters of regulated genes. Despite the wealth of information available on the function of PPARalpha and PPARgamma, relatively little is known about the most widely expressed PPAR subtype, PPARdelta. Here we show that treatment of insulin resistant db/db mice with the PPARdelta agonist L-165041, at doses that had no effect on either glucose or triglycerides, raised total plasma cholesterol concentrations. The increased cholesterol was primarily associated with high density lipoprotein (HDL) particles, as shown by fast protein liquid chromatography analysis. These data were corroborated by the chemical analysis of the lipoproteins isolated by ultracentrifugation, demonstrating that treatment with L-165041 produced an increase in circulating HDL without major changes in very low or low density lipoproteins. White adipose tissue lipoprotein lipase activity was reduced following treatment with the PPARdelta ligand, but was increased by a PPARgamma agonist. These data suggest both that PPARdelta is involved in the regulation of cholesterol metabolism in db/db mice and that PPARdelta ligands could potentially have therapeutic value.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Lipídeos/sangue , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Acetatos/farmacologia , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Colesterol/química , Colesterol/metabolismo , Cromatografia Líquida , Proteínas de Ligação a DNA/química , Ligantes , Lipase Lipoproteica/metabolismo , Lipoproteínas/química , Lipoproteínas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fenóis/farmacologia , Fenoxiacetatos , Receptores Citoplasmáticos e Nucleares/química , Fatores de Transcrição/química , Triglicerídeos/sangue , Ultracentrifugação
13.
Atherosclerosis ; 131(2): 257-62, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9199280

RESUMO

Apolipoprotein E (apo E) is a component of all the classes of lipoproteins and can be distributed among apo B- (LpB) and non apo B-containing lipoproteins (Lp-non-B). Using a new electroimmunoassay kit, plasma apo E, apo E in Lp-non-B (apo E-Lp-non-B) and apo E in LpB (apo E-LpB) levels were measured in healthy control subjects (n=481) from 3 centers participating in the ECTIM study (Etude Cas-Témoins sur l'Infarctus du Myocarde), a population-based study on myocardial infarction. The distribution of apo E among lipoproteins was analyzed according to the apo E phenotype after adjustment for center, body mass index, tobacco use, alcohol consumption and triglycerides. Apo E was higher (average excess: + 0.32; P < 0.0001) and lower (average excess: -0.12; P < 0.0001) in subjects carrying the allele epsilon2 and the allele epsilon4 respectively, than in apo E3/3 subjects. These differences are the consequence of variations in apo E-Lp-non-B which clearly differed between the groups classified according to their apo E phenotype (P < 0.0001). The average excess of apo E Lp non-B compared to apo E3/3 subjects was + 0.43 (P < 0.0001) and -0.22 (P < 0.0001) for the epsilon2 and epsilon4 alleles respectively. Apo E-LpB was lower in subjects carrying the epsilon2 allele (P < 0.02) while the presence of the epsilon4 allele did not modify this parameter. The proportion of apo E within HDL was clearly higher and lower in subjects carrying apo E2 and apo E4 respectively than in apo E3/3 subjects. Although triglyceride levels were dependent on the apo E phenotype, the adjustment of the proportion of apo E in HDL for triglycerides hardly modified the results. For the first time, these results, using direct measurements on a large number of subjects, confirm the greater preference of apo E4 over apo E2 for LpB and vice versa for Lp-non-B. They also show a greater affinity of apo E2 for HDL compared to apo E3. This high affinity of apo E2 for HDL could be due to the formation of the apo E-A-II complex. These results indicate that apo E phenotype modulates the distribution of apo E among lipoproteins and suggest differences in lipoprotein metabolism between apo E2, apo E3 and apo E4.


Assuntos
Apolipoproteínas B/sangue , Apolipoproteínas E/sangue , Apolipoproteínas E/genética , Infarto do Miocárdio/genética , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Colesterol/sangue , HDL-Colesterol/sangue , VLDL-Colesterol/sangue , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Fenótipo , Fatores de Risco , Triglicerídeos/sangue
14.
Atherosclerosis ; 141(2): 227-35, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9862171

RESUMO

This study investigates the suitability of the trimeric apolipoprotein (apo)AI(145-183) peptide that we recently described, to serve as a model to probe the relationship between apoAI structure and function. Three copies of the apoAI(145-183) unit, composed each of two amphipathic alpha-helical segments, were branched onto a covalent core matrix and the construct was recombined with phospholipids. A similar construct was made with the apoAI(102-140) peptide and used as a comparison with dimyristoylglycerophosphocholine (DMPC)-apoAI complexes. The DMPC-trimeric-apoAI(145-183) complexes had similar immunological reactivity with monoclonal antibodies directed against the 149-186 apoAI sequence (A44), suggesting that the A44 epitope is exposed similarly in both the synthetic peptide and the native apoAI complexes. The complexes generated with the trimeric-apoAI(145-183) bind specifically to HeLa cells with comparable affinity to the DMPC apoAI complexes; they are a good competitor for binding of apoAI to both HeLa cells and Fu5AH rat hepatoma cells; finally, these complexes promote cholesterol efflux from Fu5AH cells with an efficiency comparable with the apo AI/lipid complexes. To study LCAT activation by the trimeric apo AI(145-183) construct, complexes were prepared with dipalmitoylphosphatidylcholine (DPPC), cholesterol (C) and either the trimeric construct or apoAI. LCAT activation by the trimeric construct was much lower than by apo AI, possibly because the conformation of the trimeric 145-183 peptide in DPPC/C/peptide complexes does not mimic that of apoAI in the corresponding complexes. In comparison, the complexes generated with the multimeric apoAI(102-140) construct had a poor capacity to mimic the physico-chemical and biological properties of apoAI. The apoAI(102-140) construct had low affinity for lipid compared with the (145-183) construct. After association with lipids, it was a poor competitor of DMPC-apoAI complexes for cellular binding and had only limited capacity to promote cholesterol efflux. These results suggest trimeric constructs can serve as an appropriate models for apoAI, enabling further investigations and new experimental approaches to determine the structure-function relationship of apoAI.


Assuntos
Apolipoproteína A-I/metabolismo , Lipoproteínas HDL/metabolismo , Animais , Apolipoproteína A-I/química , Colesterol/metabolismo , Células HeLa , Humanos , Neoplasias Hepáticas Experimentais , Peptídeos/síntese química , Fosfatidilcolina-Esterol O-Aciltransferase/fisiologia , Conformação Proteica , Ratos , Células Tumorais Cultivadas
15.
Atherosclerosis ; 120(1-2): 209-19, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8645362

RESUMO

The goal of this study was to compare the structural and biological characteristics of apolipoprotein (apo) B-100-containing particle subfractions isolated from poorly controlled diabetic patients with insulin-dependent diabetes (IDDM), and healthy controls matched for sex, age and body mass index (BMI). Different apo B-containing particles were isolated by sequential immunochromatography and were free of apo A-I, apo A-II, apo A-IV and apo(a). Particles lipoprotein (Lp) B/C-III contained apo B and apo C-III. They were free of apo E. Particles Lp B/E contained apo B and apo E. They were free of apo C-III. Particles Lp B were devoided of apo C-III and apo E. All these particles could contain other known apolipoproteins not cited here, as for example apo C-II and/or apo C-I. The plasma levels of cholesterol, triglycerides, phospholipids, apo A-I, B-100, C-III, E, total Lp B/C-III, total Lp B/E were not different between patients and controls. The physico-chemical properties of Lp B/C-III and Lp B/E were similar in both groups. Only Lp B from patients exhibited some changes, an increase in the size and a decrease in the cholesterol and cholesteryl ester levels. The conformational properties of the lipoproteins were studied through their immunoreactivity against four different anti-apo B-100 monoclonal antibodies (MAb) for which sequential epitopes have been located on the protein, and one MAb for which the epitope is conformationally expressed. Again, minor changes were observed between patients and controls, and only a slight decrease in the immunoreactivity of the epitope encompassing amino-acid residues 405 to 539 of Lp B and of the conformationally expressed epitope of Lp B/C-III were found in patients. Nevertheless, whatever these conformational and/or physico-chemical modifications may be, they were not sufficient to induce functional alterations in the binding of the particles from the patients to the LDL-receptor of HeLa cells. This study shows that IDDM is not associated with any significant abnormalities in the apo-containing lipoprotein particles. The excessive occurrence of coronary heart disease (CHD) and other atherosclerotic vascular disease in patients with IDDM must have other causes.


Assuntos
Apolipoproteínas B/análise , Diabetes Mellitus Tipo 1/sangue , Lipoproteínas/química , Adulto , Idoso , Apolipoproteína B-100 , Arteriosclerose/etiologia , Arteriosclerose/fisiopatologia , Glicemia/análise , Doença das Coronárias/etiologia , Doença das Coronárias/fisiopatologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Células HeLa/metabolismo , Humanos , Insulina/uso terapêutico , Resistência à Insulina , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Receptores de LDL/metabolismo
16.
Atherosclerosis ; 66(1-2): 153-61, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3632747

RESUMO

The immunoreactivity of apolipoprotein B (apo B) in plasma samples obtained from a variety of subjects was analysed by non-competitive ELISA with a polyclonal and a monoclonal (BIP 45) anti-LDL antibody. Three populations were tested: the first, comprising 244 healthy male volunteers, provided reference values; the second consisted of a population undergoing coronary angiography (n = 88) and was divided into a subgroup with (n = 64) and without (n = 24) coronary artery disease (CAD); the third was made up of 56 patients with heterozygous familial hypercholesterolemia. Total apo B (measured with the polyclonal antibody) was increased in the populations with CAD and in the heterozygous familial hypercholesterolemic subjects compared to the reference population. When monoclonal antibody BIP 45 was used in the non-competitive ELISA, three different patterns emerged in each population, corresponding to weak, intermediate and strong binding of the particles containing apo B to the monoclonal antibody. This may result from genetic polymorphism of apo B, and in the reference population the data fit a model consisting of two co-dominant apo B alleles (BIP(-) and BIP(+]; the 3 subpopulations then correspond to the 2 homozygotes and the heterozygote. The number of patients whose particles bound weakly to monoclonal BIP 45 antibody was low in the CAD population, while intermediate binding was increased in this group. Nevertheless, when the analysis of variance of allele BIP(-) was studied no significant difference between groups was established. This finding indicates that the genetic difference in apo B detected by BIP 45 may not be significant in the development of CAD. Furthermore, the apo B genetic polymorphism detected by BIP 45 is not associated with a particular lipoprotein level in the reference population.


Assuntos
Anticorpos Monoclonais , Apolipoproteínas B/genética , Doença das Coronárias/genética , Lipídeos/sangue , Lipoproteínas LDL/imunologia , Polimorfismo Genético , Animais , Anticorpos Monoclonais/imunologia , Masculino , Camundongos
17.
J Immunol Methods ; 109(1): 61-8, 1988 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-2451696

RESUMO

Antibodies of predetermined specificity raised against a synthetic peptide corresponding to the C-terminal region of apolipoprotein C-II (Apo C-II) 63-79 were shown to be specific for the apolipoprotein by Western blot. The recognition by these antibodies of Apo C-II containing lipoprotein particles (both isolated and in plasma) was studied in a fluid-phase radioimmunoassay and the affinity constant for plasma was determined. The role of lipids in the expression of epitopes was studied by comparing the antigenicity of intact and delipidated Apo C-II containing fractions. The antibodies proved to be as suitable as conventional anti-protein antibodies in an immunoenzymometric assay and, moreover, were able to develop 'rockets' in an electroimmunoassay.


Assuntos
Anticorpos/isolamento & purificação , Especificidade de Anticorpos , Apolipoproteínas C/imunologia , Fragmentos de Peptídeos/imunologia , Afinidade de Anticorpos , Apolipoproteína C-II , Apolipoproteínas C/sangue , Sítios de Ligação de Anticorpos , Ligação Competitiva , Epitopos/análise , Epitopos/imunologia , Humanos , Imunoeletroforese/métodos , Técnicas Imunoenzimáticas , Lipoproteínas HDL/fisiologia , Lipoproteínas VLDL/fisiologia
18.
Am J Med ; 83(5B): 71-4, 1987 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-3688011

RESUMO

The effect of treatment with fenofibrate was investigated in nine patients (seven men) presenting with type III hyperlipoproteinemia. This therapy produced a statistically significant decrease in serum triglyceride, cholesterol, apolipoproteins B, CII, CIII, and E levels. Particular attention was focused on lipoproteins containing apolipoprotein B. The concentration of particles recognized by monoclonal antibodies (BL3, BL5, and BL7), associated with atherosclerotic disease, was lowered by the treatment. The most dramatic decrease was observed for lipoproteins LpE:B and LpCIII:B, which are particularly enhanced in type III hyperlipoproteinemia.


Assuntos
Fenofibrato/uso terapêutico , Hiperlipoproteinemia Tipo III/tratamento farmacológico , Propionatos/uso terapêutico , Adulto , Idoso , Apolipoproteínas/sangue , Colesterol/sangue , Feminino , Humanos , Hiperlipoproteinemia Tipo III/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
19.
Am J Med ; 93(3): 259-62, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1524076

RESUMO

PURPOSE: To assess an independent relationship between shift work and serum lipid levels. DESIGN: Cross-sectional survey. SETTING: Two plants of northern France: a chemical one and a nuclear power station. PARTICIPANTS: All the shift workers of the chemical plant and of one part of the nuclear station. One hundred nine persons were selected, 25 were excluded or absent during the study, and 11 refused to participate. Day workers matched with shift workers according to age, educational level, birthplace, and occupational physical activity level served as controls; 109 were selected, 26 were excluded or absent, and 10 refused to participate. MAIN OUTCOME MEASURES: Fasting venous plasma concentration of total cholesterol, triglyceride, and high-density lipoprotein (HDL) cholesterol; dietary intake assessed by a 3-day record, smoking habits, and body mass index (BMI). RESULTS: Shift workers had significantly higher levels of serum triglyceride (1.26 versus 1.03 mmol/L, p = 0.01). Cholesterol and HDL cholesterol levels were similar for the two groups. There was no difference in energy and nutrient intake, but day workers had a higher alcohol intake (15.64 g/d versus 9.3 g/d, p = 0.03). Multivariate analysis conducted with triglycerides as dependent variable and shift work, BMI, smoking, age, leisure time physical activity level, energy intake, and alcohol intake as independent variables confirmed that shift work has a significant explanatory power for triglyceride levels (beta = 0.134, p = 0.0005). CONCLUSION: This study confirms that shift work is associated with an increase of triglyceride levels independent of dietary intake. We did not find any influence of shift work on cholesterol and HDL cholesterol. Despite this latter fact, our findings are to be considered in the explanation of coronary risk among shift workers. Further studies are needed to elucidate the mechanism of this relative hypertriglyceridemia: stress induced by shift work or diurnal rhythm disturbances.


Assuntos
Triglicerídeos/sangue , Tolerância ao Trabalho Programado/fisiologia , Adulto , Fatores Etários , Pressão Sanguínea , Índice de Massa Corporal , Estudos Transversais , Dieta , Humanos , Masculino , Fumar
20.
Metabolism ; 45(4): 430-4, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8609827

RESUMO

Insulin-dependent diabetes mellitus (IDDM) is characterized by altered composition of atherogenic lipoproteins, especially a depletion in choline-containing phospholipids (PL) of apolipoprotein (apo) B lipoproteins (LpB). To determine the effects of continuous intraperitoneal (IP) insulin infusion (CIPII) on this qualitative lipoprotein abnormality, we compared lipoprotein profiles of 14 IDDM patients treated by continuous subcutaneous insulin infusion (CSII) and at 2 and 4 months after treatment with CIPII using an implantable pump. IDDM patients were in fair metabolic control and were compared with 14 healthy control subjects matched for sex, age, body mass index, and plasma lipids. The following parameters were studies: hemoglobin A1c (HbA1c), monthly blood glucose, daily insulin dose (units per kilogram per day), total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol, apo A-I, and apo B. Choline-containing PL were assessed in plasma and in apo B- and no-apo B-containing lipoprotein particles (LpB and Lp no B). As compared with the control group, plasma PL and LpB-PL were significantly lower in IDDM patients treated by CSII (2.95 +/- 0.26 v 3.30 +/- 0.45 mmol/L,P<.05, and 1.09 +/- 0.45 v 1.68 +/- 0.33 mmol/L,P<.01, respectively). No significant differences were observed for Lp no B lipid determinations between both groups. After initiation of CIPII, IDDM patients did not experience any significant changes in mean values for body mass index, HbA1c, and monthly blood glucose throughout the study. Daily insulin doses were identical to those observed before IP therapy. Lipid parameters remained unchanged in IDDM patients (TC, TG, HDL and LDL cholesterol, apo A-I, and apo B). A moderate but progressive elevation of plasma PL was noted, and after 4 months of CIPII, PL and LpB-PL levels were no longer significantly different between IDDM patients and controls. The increase in plasma and LpB choline-containing PL observed after 2 and 4 months of CIPII is not linked to changes in blood glucose control, body weight or daily insulin requirements. These changes may be related to the route of insulin administration, which may be accompanied by a reduction of lipoprotein lipase (LPL) activity and consequently a reduction of phospholipase activity. These results suggest that IP insulin delivery may be a more physiological route that increases the choline-containing PL content of LpB particles.


Assuntos
Apolipoproteínas B/metabolismo , Colina/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Insulina/farmacologia , Fosfolipídeos/metabolismo , Adulto , Apolipoproteínas B/sangue , Glicemia/análise , Índice de Massa Corporal , Colesterol/sangue , Colina/análise , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Humanos , Bombas de Infusão Implantáveis , Infusões Parenterais , Insulina/administração & dosagem , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Fosfolipídeos/química , Fatores de Tempo , Triglicerídeos/sangue
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