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1.
Artigo em Inglês | MEDLINE | ID: mdl-36498219

RESUMO

The aim of the study was to explore in depression the relationship between recent suicidal ideation and the different anhedonias taking into account the severity of depression. Recent studies have suggested that recent change of anhedonia and not state or trait anhedonia is associated with recent suicidal ideations even when the level of depression is controlled. Three samples were used (74 severe major depressives, 43 outpatients with somatic disorders presenting mild or moderate depression and 36 mild or moderate depressives hospitalized in the intensive coronary unit). Recent change of anhedonia was rated by the anhedonia subscale of the Beck Depression Inventory (BDI-II), state anhedonia by the Snaith-Hamilton Pleasure Scale (SHAPS), trait anhedonia by the TEPS (Temporal Experience of Pleasure Scale), musical anhedonia by the BMRQ (Barcelona Music Reward Questionnaire), social recent change of anhedonia by the SLIPS (Specific Loss of Interest and Pleasure Scale), the severity of depression by the BDI-II and the distinction between melancholic and non-melancholic was found using a subscale of the BDI-II. Bivariate and multivariate regression analyses were performed in each sample. In severe major depressives and, notably, in melancholia, recent suicidal ideation was associated with trait anhedonia; however, in mild or moderate depression, recent suicidal ideation was associated with recent change of anhedonia. Musical anhedonia and social recent change of anhedonia were not associated with recent suicidal ideation. Trait anhedonia could be, in severe depression, a strong predictor of recent suicidal ideation.


Assuntos
Transtorno Depressivo , Ideação Suicida , Humanos , Anedonia , Escalas de Graduação Psiquiátrica , Prazer
2.
Brain ; 142(12): 3806-3833, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31665242

RESUMO

Microglia of the developing brain have unique functional properties but how their activation states are regulated is poorly understood. Inflammatory activation of microglia in the still-developing brain of preterm-born infants is associated with permanent neurological sequelae in 9 million infants every year. Investigating the regulators of microglial activation in the developing brain across models of neuroinflammation-mediated injury (mouse, zebrafish) and primary human and mouse microglia we found using analysis of genes and proteins that a reduction in Wnt/ß-catenin signalling is necessary and sufficient to drive a microglial phenotype causing hypomyelination. We validated in a cohort of preterm-born infants that genomic variation in the Wnt pathway is associated with the levels of connectivity found in their brains. Using a Wnt agonist delivered by a blood-brain barrier penetrant microglia-specific targeting nanocarrier we prevented in our animal model the pro-inflammatory microglial activation, white matter injury and behavioural deficits. Collectively, these data validate that the Wnt pathway regulates microglial activation, is critical in the evolution of an important form of human brain injury and is a viable therapeutic target.


Assuntos
Encéfalo/metabolismo , Inflamação/metabolismo , Microglia/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Animais Geneticamente Modificados , Barreira Hematoencefálica/metabolismo , Células Cultivadas , Biologia Computacional , Humanos , Camundongos , Peixe-Zebra
3.
Arch Cardiovasc Dis ; 111(11): 634-643, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29198936

RESUMO

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) reduction is an integral part of the management of patients with coronary artery disease (CAD). AIMS: To assess attainment of LDL-C goals during long-term treatment of patients with stable CAD, and to determine predictors of goal attainment and the prognostic impact of reaching LDL-C<70mg/dL (1.8mmol/L) in a real-life setting. METHODS: Data were obtained for 4080 outpatients with stable CAD included in the multicentre CORONOR study. Five-year follow-up was achieved for 3991 (97.8%) patients. RESULTS: At inclusion, a recent (<1 year) measurement of LDL-C was available in 3757 (92.1%) patients. LDL-C<70mg/dL was reached by 885 (23.6%) patients. Independent predictors of LDL-C<70mg/dL were diabetes mellitus, statin treatment, treatment with renin-angiotensin system inhibitors, previous myocardial infarction and short time since last coronary event. The adjusted hazard ratio (HR) for the composite endpoint (cardiovascular death, myocardial infarction, ischemic stroke or coronary revascularization) during the 5-year follow-up was 1.31 (95% confidence interval [CI]: 1.09-1.58; P=0.004) for LDL-C≥70mg/dL versus<70mg/dL. When compared with patients with LDL-C<70mg/dL, the adjusted HRs for LDL-C 70-99mg/dL and ≥100mg/dL (2.6mmol/L) were 1.27 (95% CI: 1.05-1.55; P=0.016) and 1.38 (95% CI: 1.12-1.70; P=0.003), respectively. When LDL-C was used as a continuous variable, the adjusted HRs for increases of 10mg/dL (0.3mmol/L) and 1mmol/L were 1.05 (95% CI: 1.03-1.08) and 1.21 (95% CI: 1.10-1.33), respectively. CONCLUSIONS: In this observational study, only a minority of stable CAD patients had LDL-C<70mg/dL. The patients who reached their LDL-C goal had the lowest risk of cardiovascular events.


Assuntos
LDL-Colesterol/sangue , Doença da Artéria Coronariana/terapia , Dislipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Prevenção Secundária/métodos , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/mortalidade , Regulação para Baixo , Dislipidemias/sangue , Dislipidemias/diagnóstico , Dislipidemias/mortalidade , Feminino , França , Humanos , Hipolipemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
4.
Arch Cardiovasc Dis ; 110(3): 149-156, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28117245

RESUMO

BACKGROUND: Cardiovascular events related to high-intensity sport practice are rare but dramatic. Coronary artery disease (CAD) is the leading cause of these events after the age of 35 years. The value of a maximal exercise test (ET) for detection of athletes at risk remains a matter of debate. AIM: The aim of this prospective multicentre study was to clarify the medical value and cost-effectiveness of an ET in middle-aged white asymptomatic athletes who participate in high-intensity sport. METHODS: All athletes had a physical examination, assessment of cardiovascular risk factors, a resting electrocardiogram and an ET. In case of abnormal ET, complementary cardiovascular evaluation was performed, when requested, to detect potential cardiovascular disease. RESULTS: 1361 asymptomatic athletes (mean age 50.4±9.6 years; mean training 5.1±3.2h/week; 10.4% women) with a normal resting electrocardiogram and without cardiovascular disease were consecutively included. An abnormal ET was reported in 144 subjects (94% men); this was positively related to the subject's age and cardiovascular risk level. Cardiac arrhythmias (48%) and CAD symptoms (33.3%) were mainly reported. Cardiovascular disease was confirmed in 24 cases (1.7% from the whole population; 16.7% from those with an abnormal ET) - mainly CAD (n=12) and arterial hypertension (n=8). Seventy athletes presented significant unexplained arrhythmias. The cost was approximately €8450 for every confirmed case of cardiovascular disease. CONCLUSIONS: In this multicentre study in middle-aged athletes, a systematic ET was abnormal in 10.6% of cases. About 2% of subjects had cardiovascular disease, mainly arrhythmias and CAD. From these results, it seems that in a trained population aged >35 years, ET should be targeted at men with at least two cardiovascular risk factors, with acceptable cost-effectiveness.


Assuntos
Arritmias Cardíacas/diagnóstico , Atletas , Doença da Artéria Coronariana/diagnóstico , Teste de Esforço/economia , Custos de Cuidados de Saúde , Adulto , Idoso , Arritmias Cardíacas/economia , Arritmias Cardíacas/mortalidade , Arritmias Cardíacas/fisiopatologia , Doenças Assintomáticas , Pressão Sanguínea , Doença da Artéria Coronariana/economia , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/fisiopatologia , Análise Custo-Benefício , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia/economia , Feminino , França , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco
5.
Arch Cardiovasc Dis ; 108(6-7): 340-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25858539

RESUMO

BACKGROUND: In patients with coronary artery disease (CAD), non-optimal use of evidence-based medications is associated with an increased risk of adverse outcome. AIMS: To assess the prevalence and correlates of non-optimal secondary medical prevention in patients with stable CAD. METHODS: We included 4184 consecutive outpatients with stable CAD. Treatment at inclusion was classified as optimal/non-optimal regarding the four major classes of secondary prevention drugs: antithrombotics; statins; angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs); and beta-blockers. For each treatment, the prescription was considered non-optimal if the drug was missing despite a class IA indication according to international guidelines. To assess the information globally, non-optimal secondary prevention was defined as at least one major treatment missing. RESULTS: The proportions of patients with non-optimal treatment were 0.7%, 7.8%, 12.9% and 10.3% for antithrombotics, statins, ACE inhibitors/ARBs and beta-blockers, respectively. Non-optimal secondary medical prevention was observed in 16.8% of cases. By multivariable analysis, the correlates of non-optimal secondary medical prevention were long time interval since last coronary event (P<0.0001), older age (P<0.0001), diabetes mellitus (P<0.0001), hypertension (P<0.0001), no history of myocardial infarction (P=0.001), no history of coronary revascularization (P=0.013) and low glomerular filtration rate (P=0.042). CONCLUSIONS: Although most patients with stable CAD are receiving evidence-based medications according to guidelines, there remain subgroups at higher risk of non-optimal treatment. In particular, it might be feasible to improve prevention by focusing on patients in whom a long time has elapsed since the last coronary event.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Doença das Coronárias/terapia , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Idoso , Comorbidade , Diabetes Mellitus/epidemiologia , Uso de Medicamentos , Medicina Baseada em Evidências , Feminino , França , Fidelidade a Diretrizes , Humanos , Hipertensão/epidemiologia , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Infarto do Miocárdio/epidemiologia , Revascularização Miocárdica/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Recidiva , Fatores de Risco , Prevenção Secundária , Resultado do Tratamento
6.
Steroids ; 76(1-2): 28-30, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20727907

RESUMO

The synthesis of 7ß-hydroxy-epiandrosterone (6) possessing strong anti-inflammatory properties was achieved starting from 3ß-acetoxy-17,17-(ethylenedioxy)-5-androsten (1). This approach involved as a main step an allylic oxidation of the C-7 followed by two reduction reactions of the double bond and of the carbonyl group. This stereoselective synthesis in 5 steps gave 7ß-hydroxy-epiandrosterone in 63% overall yield.


Assuntos
Androsterona/análogos & derivados , Androsterona/síntese química , Androsterona/química , Conformação Molecular , Estereoisomerismo
7.
Horm Mol Biol Clin Investig ; 7(1): 295-301, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25961267

RESUMO

In order to develop an immunoassay of 7ß-hydroxy-epiandrosterone, a stereoselective synthesis of a specific hapten, 7ß-hydroxy-19-oxo-androstan 19-(O-carboxymethyl)oxime (17), was performed. This synthesis was achieved in 16% overall yield starting from the well-known 3ß-acetoxy-19-hydroxy-5-androsten-17-one (1). After coupling of the alkyl oxime moiety, an allylic oxidation of the C-7 carbon under mild conditions followed by two selective reductions established all the functionalities of the final compound 17.

8.
Horm Mol Biol Clin Investig ; 4(1): 489-98, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25961225

RESUMO

Numerous studies investigated the effects of pharmacological doses of DHEA in animals. Among protective effects, antiglucocorticoid potencies, triggering and modulation of immunity and anticancerous effects were reported. Because DHEA levels decrease in aging humans, this steroid has been assayed as replacement therapy in elderly volunteers without striking evidence for beneficial effects. Examination of the investigations carried out in animals lead to suspect that, rather than DHEA, its metabolites produced in tissues could be responsible for some of the observed effects. Known as the "mother steroid", DHEA is a precursor for androgenic and estrogenic steroid hormones. In addition, DHEA is hydroxylated at the 7α position by the cytochrome P450 7B1 (CYP7B1), and the 7α-hydroxy-DHEA produced is a substrate for the 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) which converts it into 7ß-hydroxy-DHEA. Both 7-hydroxylated metabolites were shown to favor the onset of immunity in mice and the activation of memory T cells in humans. Other DHEA and testosterone-derived metabolites, namely epiandrosterone and 5α-androstane-3ß,17ß-diol, are also substrates for the CYP7B1 and their 7α-hydroxylated products were also converted into the 7ß epimer by the 11ß-HSD1. When assayed at doses 104 lower than DHEA, 7ß-hydroxy-epiandrosterone was shown to shift the prostaglandin metabolism patterns from prostaglandin E2 (PGE2) to PGD2 production, thus triggering the resolution of inflammation. In addition, 7ß-hydroxy-epiandrosterone (1 nM) exerted the same effects as tamoxifen (1 µM) on the proliferation of MCF-7 and MDA-231 human breast cancer cells. These findings suggest that the observed effects of 7ß-hydroxy-epiandrosterone could be mediated by estrogen receptors. This overview of recent research implies that DHEA does not act directly and that its effects are due to its metabolites when produced in tissues. Treatments with DHEA should take into account the target tissue abilities to produce the desired metabolites through the two key enzymes, CYP7B1 and 11ß-HSD1.

9.
Horm Mol Biol Clin Investig ; 1(1): 11-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25961967

RESUMO

Inflamed tissues produce both prostaglandins (PGs) and 7α-hydroxylated derivatives of native circulating 3ß-hydroxysteroids. These 7α-hydroxysteroids are in turn transformed into 7ß-hydroxylated epimers by 11ß-hydroxysteroid dehydrogenase type 1 in the tissue. 7ß-Hydroxy-epiandrosterone (7ß-hydroxy-EpiA) affects PG production in two models of inflammation, dextran sodium sulfate-induced colitis in the rat and TNF-α-induced activation of PG production and PG synthase expression in cultured human peripheral blood monocytes (hPBMC). Treatment with 7ß-hydroxy-EpiA led to a shift from high to low colonic PGE2 levels and from low to high 15-deoxy-Δ12-14-PGJ2 (15d-PGJ2) levels, together with changes in the expression of the respective PG synthases and resolution of colonic inflammation. Addition of 7ß-hydroxy-EpiA to hPBMC also changed the expression of PG synthases and decreased PGE2 while increasing 15d-PGJ2 production. These effects were only observed with 7ß-hydroxy-EpiA and not with 7α-hydroxy- or 7ß-hydroxy-dehydroepiandrosterone (7α-hydroxy-DHEA and 7ß-hydroxy-DHEA). 15d-PGJ2, which is the native ligand for peroxisome proliferator-activated receptor subtype γ, contributes to cell protection and to the resolution of inflammation. Our results therefore suggest that 7ß-hydroxy-EpiA may facilitate inflammatory resolution by shifting PG production from PGE2 to PGD2 and 15d-PGJ2. The finding that 7ß-hydroxy-EpiA was effective at nM concentrations, whereas the two structurally closely related hydroxysteroids 7α-hydroxy-DHEA and 7ß-hydroxy-DHEA were inactive suggests that the effects of 7ß-hydroxy-EpiA are specific to this steroid and may be mediated by a specific receptor.

10.
J Steroid Biochem Mol Biol ; 114(1-2): 57-63, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19167490

RESUMO

Cytochrome P4507B1 7alpha-hydroxylates dehydroepiandrosterone (DHEA), epiandrosterone (EpiA) and 5alpha-androstane-3beta,17beta-diol (Adiol). 11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) interconverts 7alpha- and 7beta-forms. Whether the interconversion proceeds through oxido-reductive steps or epimerase activity was investigated. Experiments using [(3)H]-labelled 7beta-hydroxy-DHEA, 7beta-hydroxy-EpiA and 7beta-hydroxy-Adiol showed the (3)H-label to accumulate in the 7-oxo-DHEA trap but not in 7-oxo-EpiA or 7-oxo-Adiol traps. Computed models of 7-oxygenated steroids docked in the active site of 11beta-HSD1 either in a flipped or turned form relative to cortisone and cortisol. 7-Oxo-steroid reduction in 7alpha- or 7beta-hydroxylated derivatives resulted from either turned or flipped forms. 11beta-HSD1 incubation in H(2)(18)O medium with each 7-hydroxysteroid did not incorporate (18)O in 7-hydroxylated derivatives of EpiA and Adiol independently of the cofactor used. Thus oxido-reductive steps apply for the interconversion of 7alpha- and 7beta-hydroxy-DHEA through 7-oxo-DHEA. Epimerization may proceed on the 7-hydroxylated derivatives of EpiA and Adiol through a mechanism involving the cofactor and Ser(170). The physiopathological importance of this epimerization process is related to 7beta-hydroxy-EpiA production and its effects in triggering the resolution of inflammation.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Esteroide Hidroxilases/metabolismo , Esteroides , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/química , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Androstano-3,17-diol/química , Androstano-3,17-diol/metabolismo , Androsterona/química , Androsterona/metabolismo , Domínio Catalítico , Família 7 do Citocromo P450 , Desidroepiandrosterona/química , Desidroepiandrosterona/metabolismo , Humanos , Hidroxilação , Estrutura Molecular , Oxirredução , Esteroide Hidroxilases/genética , Esteroides/química , Esteroides/metabolismo
11.
Steroids ; 73(11): 1148-59, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18555503

RESUMO

7alpha-Hydroxy-DHEA, 7beta-hydroxy-DHEA and 7beta-hydroxy-EpiA are native metabolites of dehydroepiandrosterone (DHEA) and epiandrosterone (EpiA). Since numerous steroids are reported to interfere with inflammatory and immune processes, our objective was to test the effects of these hydroxysteroids on prostaglandin (PG) production and related enzyme gene expression. Human peripheral blood monocytes were cultured for 4 and 24 h in the presence of each of the steroids (1-100 nM), with and without addition of TNF-alpha (10 ng/mL). Levels of PGE(2), PGD(2) and 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)) were measured in the incubation medium, and cell content of cyclooxygenase (COX-2), and PGE and PGD synthases (m-PGES1, H-PGDS, L-PGDS), and peroxisome proliferator activated receptor (PPAR-gamma) was assessed by quantitative RT-PCR and Western blots. Addition of TNF-alpha resulted in elevated PG production and increased COX-2 and m-PGES1 levels. Among the three steroids tested, only 7beta-hydroxy-EpiA decreased COX-2, m-PGES1 and PPAR-gamma expression while markedly decreasing PGE(2) and increasing 15d-PGJ(2) production. These results suggest that 7beta-hydroxy-EpiA is a native trigger of cellular protection through simultaneous activation of 15d-PGJ(2) and depression of PGE(2) synthesis, and that these effects may be mediated by activation of a putative receptor, specific for 7beta-hydroxy-EpiA.


Assuntos
Androsterona/análogos & derivados , Dinoprostona/biossíntese , Expressão Gênica/efeitos dos fármacos , Monócitos/metabolismo , Prostaglandina D2/biossíntese , Androsterona/química , Androsterona/metabolismo , Androsterona/farmacologia , Células Cultivadas , Meios de Cultura/análise , Meios de Cultura/química , Ciclo-Oxigenase 2/análise , Ciclo-Oxigenase 2/biossíntese , Dinoprostona/análise , Dinoprostona/química , Dinoprostona/genética , Relação Dose-Resposta a Droga , Humanos , Oxirredutases Intramoleculares/análise , Oxirredutases Intramoleculares/biossíntese , Lipocalinas/análise , Lipocalinas/biossíntese , Modelos Biológicos , Estrutura Molecular , Monócitos/efeitos dos fármacos , PPAR gama/análise , Prostaglandina D2/análogos & derivados , Prostaglandina D2/análise , Prostaglandina D2/química , Prostaglandina D2/genética , Prostaglandina-E Sintases , Fatores de Tempo , Fator de Necrose Tumoral alfa/farmacologia
12.
J Steroid Biochem Mol Biol ; 110(3-5): 255-62, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18502118

RESUMO

High dose levels of dehydroepiandrosterone and its 7-hydroxylated derivatives have been shown to reduce oxidative stress and inflammatory responses in dextran sodium sulfate (DSS)-induced colitis in rats. Another endogenous steroid, 7beta-hydroxy-epiandrosterone (7beta-hydroxy-EpiA) has been shown to exert neuroprotective effects at much smaller doses. Our aims were to evaluate whether 7beta-hydroxy-EpiA pre-treatment prevents DSS-induced colitis and to determine whether the effects involve changes in anti-inflammatory prostaglandin (PG) D(2) and 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)) levels. Rats were administered 0.01, 0.1 and 1mg/kg 7beta-hydroxy-EpiA i.p. once a day for 7 days. Thereafter, colitis was induced by administration of 5% DSS in drinking water for 7 days. Levels of the PGs and the expression of cyclooxygenase (COX-2) and PG synthases were assessed during the course of the experiment. Administration of 7beta-hydroxy-EpiA caused a transient increase in COX-2 and PGE synthase expression within 6-15h and augmented colonic tissue levels of 15d-PGJ(2) levels starting at day 2. Treatment with DSS resulted in shortened colon length, depleted mucus in goblet cells and induced oxidative stress. COX-2 and mPGES-1 synthase expression were enhanced and accompanied by increased PGE(2), D(2) and 15d-PGJ(2) production. Although all dose levels of 7beta-hydroxy-EpiA reduced PGE(2) production, only the lowest dose (0.01mg/kg) of the steroid completely prevented colitis damage and tissue inflammation. 7beta-Hydroxy-EpiA pre-treatment prevents the occurrence of DSS-induced colitis through a shift from PGE(2) to PGD(2) production, associated with an early but transient increase in COX-2 expression and a sustained increase in the production of the anti-inflammatory prostaglandin 15d-PGJ(2).


Assuntos
Androsterona/análogos & derivados , Androsterona/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Prostaglandinas/metabolismo , Algoritmos , Androsterona/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Colite/induzido quimicamente , Colite/metabolismo , Colite/prevenção & controle , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citoproteção/efeitos dos fármacos , Sulfato de Dextrana , Avaliação Pré-Clínica de Medicamentos , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Lipocalinas/genética , Lipocalinas/metabolismo , Masculino , Prostaglandinas/sangue , Ratos , Ratos Wistar
13.
Steroids ; 72(13): 855-64, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17825335

RESUMO

Several studies have shown that the native 7alpha-hydroxy-dehydroepiandrosterone (7alpha-hydroxy-DHEA) is a substrate for the human 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) which converts the 7alpha- into the 7beta-epimer through an oxido-reduction process. Research on the 11beta-HSD1 has investigated its function and structure through using native glucocorticoid substrates and known inhibitors. Other steroid substrates are also of interest. Among testosterone metabolites, 5alpha-androstane-3beta,17beta-diol (Adiol) is a substrate for the cytochrome P450 7B1 which produces 5alpha-androstane-3beta,7alpha,17beta-triol (7alpha-Adiol). This steroid may be a substrate for the 11beta-HSD1. We used recombinant yeast-expressed 11beta-HSD1 with NADP(H)-regenerating systems for examining the products obtained after incubation with 7alpha-Adiol, 7beta-Adiol or 7-oxo-Adiol. Oxidative conditions for the 11beta-HSD1 provided no trace of 7-oxo-Adiol but the inter-conversion of 7alpha- and 7beta-hydroxy-Adiol with V(max)/K(M) (pmol min(-1) microg(-1)/microM) values of 2 and 0.5, respectively. This state was maintained under reductive conditions. The use of a 7-oxo-Adiol substrate under reductive conditions led to the production of both 7alpha- and 7beta-hydroxy-Adiol with V(max)/K(M) values of 3.43 and 0.22, respectively. These findings support the hypothesis that the oxido-reductase and epimerase activities of 11beta-HSD1 depend on the positioning of the steroid substrates within the active site and may provide insight into its fine structure and mechanism of action.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/química , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/química , Humanos , Cinética , Especificidade por Substrato , Água/química
14.
Am Heart J ; 154(3): 589-95, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17719311

RESUMO

BACKGROUND: Previous studies, with limited number of patients, have tried to determine the predictors of left ventricular ejection fraction (LVEF) improvement after beta-blockade. No study has demonstrated that LVEF improvement was an independent predictor of cardiac survival. METHODS: The aims of the study were to determine in a large group of patients with stable chronic heart failure associated with reduced LVEF the predictors of LVEF improvement (difference in LVEF [deltaLVEF], ie, the value after beta-blockade minus the value before beta-blockade) after beta-blockade and to analyze prognostic impact of deltaLVEF. Three hundred fourteen consecutive patients underwent an echocardiogram, a radionuclide angiogram, and a maximum cardiopulmonary exercise test before and 3 months after maximal tolerated doses of beta-blockers have been reached. RESULTS: After beta-blockade, LVEF improved from 30% +/- 11% to 40% +/- 13%. In the whole population, independent predictors of deltaLVEF were nonischemic etiology, baseline LVEF (negative correlation), and baseline heart rate (positive correlation). In ischemic patients, independent predictors of deltaLVEF were absence of history of myocardial infarction, baseline heart rate, and baseline LVEF; whereas in nonischemic patients, independent predictors were baseline LVEF and baseline QRS width (negative correlation). After 1082 days of follow-up, there were 53 cardiovascular deaths and 2 urgent transplantations. Left ventricular ejection fraction improvement (defined as an absolute increase in LVEF > 5%) was an independent predictor of cardiac survival. Patients who had an LVEF < or = 45% after beta-blockade with a deltaLVEF < or = 5% represented a high-risk subgroup. CONCLUSIONS: In patients with chronic heart failure, predictors of LVEF improvement after beta-blockade were different according to etiology. Left ventricular ejection fraction improvement was an independent predictor of cardiac survival.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Bisoprolol/uso terapêutico , Carbazóis/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Propanolaminas/uso terapêutico , Volume Sistólico , Carvedilol , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
15.
J Steroid Biochem Mol Biol ; 105(1-5): 159-65, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17624766

RESUMO

The human 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) catalyzes both the NADP(H)-dependent oxido-reduction of cortisol and cortisone and the inter-conversion of 7alpha- and 7beta-hydroxy-dehydroepiandrosterone (DHEA) through a 7-oxo-DHEA intermediate. As shown with human liver and intestine fractions, 7alpha-hydroxy-epiandrosterone (7alpha-hydroxy-EpiA) and 7beta-hydroxy-EpiA were readily inter-converted with no evidence for a 7-oxo-EpiA intermediate. Whether this inter-conversion resulted from action of the 11beta-HSD1 or from an unknown epimerase is unresolved. Furthermore, whether these steroids could inhibit the cortisol-cortisone oxido-reduction remains a question. The recombinant human 11beta-HSD1 was used to test these questions. NADP(+) supplementation only provided the production of 7beta-hydroxy-EpiA out of 7alpha-hydroxy-EpiA with a V(max)/K(M) ratio at 0.1. With NADPH supplementation, both 7alpha-hydroxy-EpiA and 7beta-hydroxy-EpiA were formed in low amounts from 7beta-hydroxy-EpiA and 7alpha-hydroxy-EpiA, respectively. These inter-conversions occurred without a trace of the putative 7-oxo-EpiA intermediate. In contrast, the 7-oxo-EpiA substrate was efficiently reduced into 7alpha-hydroxy-EpiA and 7beta-hydroxy-EpiA, with V(max)/K(M) ratios of 23.6 and 5.8, respectively. Competitive and mixed type inhibitions of the 11beta-HSD1-mediated cortisol oxidation were exerted by 7alpha-hydroxy-EpiA and 7beta-hydroxy-EpiA, respectively. The 11beta-HSD1-mediated cortisone reduction was inhibited in a competitive manner by 7-oxo-EpiA. These findings suggest that the active site of the human 11beta-HSD1 may carry out directly the epimeric transformation of 7-hydroxylated EpiA substrates. The low amounts of these steroids in human do not support a physiological importance for modulation of the glucocorticoid status in tissues.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Androsterona/metabolismo , Inibidores Enzimáticos/farmacologia , Sequência de Bases , Cortisona/metabolismo , Primers do DNA , Humanos , Hidrocortisona/metabolismo , Cinética , Especificidade por Substrato
16.
J Steroid Biochem Mol Biol ; 104(3-5): 326-33, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17467270

RESUMO

Dehydroepiandrosterone (DHEA) is 7alpha-hydroxylated by the cytochome P450 7B1 (CYP7B1) in the human brain and liver. This produces 7alpha-hydroxy-DHEA that is a substrate for 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) which exists in the same tissues and carries out the inter-conversion of 7alpha- and 7beta-hydroxy-DHEA through a 7-oxo-intermediary. Since the role of 11beta-HSD1 is to transform the inactive cortisone into active cortisol, its competitive inhibition by 7alpha-hydroxy-DHEA may support the paradigm of native anti-glucocorticoid arising from DHEA. Therefore, our objective was to use human tissues to assess the presences of both CYP7B1 and 11beta-HSD1. Human skin was selected then and used to test its ability to produce 7alpha-hydroxy-DHEA, and to test the interference of 7alpha- and 7beta-hydroxy-DHEA and 7-oxo-DHEA with the 11beta-HSD1-mediated oxidoreduction of cortisol and cortisone. Immuno-histochemical studies showed the presence of both CYP7B1 and 11beta-HSD1 in the liver, skin and tonsils. DHEA was readily 7alpha-hydroxylated when incubated using skin slices. A S9 fraction of dermal homogenates containing the 11beta-HSD1 carried out the oxidoreduction of cortisol and cortisone. Inhibition of the cortisol oxidation by 7alpha-hydroxy-DHEA and 7beta-hydroxy-DHEA was competitive with a Ki at 1.85+/-0.495 and 0.255+/-0.005 microM, respectively. Inhibition of cortisone reduction by 7-oxo-DHEA was of a mixed type with a Ki at 1.13+/-0.15 microM. These findings may support the previously proposed native anti-glucocorticoid paradigm and suggest that the 7alpha-hydroxy-DHEA production is a key for the fine tuning of glucocorticoid levels in tissues.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Desidroepiandrosterona/metabolismo , Esteroide Hidroxilases/metabolismo , Cortisona/metabolismo , Família 7 do Citocromo P450 , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/farmacologia , Feminino , Humanos , Hidrocortisona/metabolismo , Hidroxilação , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Oxirredução , Pele/enzimologia , Pele/metabolismo
17.
J Steroid Biochem Mol Biol ; 100(1-3): 95-105, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16713254

RESUMO

Circulating 3beta-hydroxysteroids including dehydroepiandrosterone (DHEA) are 7alpha-hydroxylated by the cytochrome P450-7B1 in the liver, skin and brain, which are the target organs of glucocorticoids. Anti-glucocorticoid effects with 7alpha-hydroxy-DHEA were observed in vivo without an interference with glucocorticoid binding to its receptor. In the organs mentioned above, the circulating inactive cortisone was reduced into active cortisol by the 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). We demonstrated that 7alpha-hydroxy-DHEA was also a substrate for this enzyme. Studies of the 11beta-HSD1 action on 7alpha-hydroxy-DHEA showed the reversible production of 7beta-hydroxy-DHEA through an intermediary 7-oxo-DHEA, and the kinetic parameters favored this production over that of active glucocorticoids. Both the production of 7alpha-hydroxysteroids and their interference with the activation of cortisone into cortisol are basic to the concept of native anti-glucocorticoids efficient at their production site. This opens a promising new area for research.


Assuntos
Desidroepiandrosterona/metabolismo , Glucocorticoides/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Envelhecimento/metabolismo , Animais , Encéfalo/metabolismo , Cortisona/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Família 7 do Citocromo P450 , Humanos , Hidrocortisona/metabolismo , Cinética , Fígado/metabolismo , Modelos Biológicos , Receptores de Glucocorticoides/metabolismo , Pele/metabolismo , Esteroide Hidroxilases/metabolismo , Especificidade por Substrato
18.
Neurosci Lett ; 374(2): 109-12, 2005 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-15644274

RESUMO

Alcohol exposition during pregnancy has irreversible effects on the fetus brain. In hamsters, intrapallial injection of the glutamate receptor agonist ibotenic acid (100ng) on the day of birth (P0) induced neuronal migration disorders. In utero alcohol (7%) exposure from day 5 of gestation to P5, enhanced lesions size measured in pups' brain at P5. The administration for the same period of the taurine derivative acamprosate together with alcohol or in water to pregnant females reduced the rate of occurrence of nodular heterotopia, sub-pial ectopia and microgyria in non-alcohol-exposed pups. In addition acamprosate diminished lesion size in alcohol-exposed and non-exposed pups. A significant dose-related effect of acamprosate was observed. In addition, acamprosate rescued 27% of the pups injected with 10 microg ibotenic acid, a lethal dose in alcohol-exposed animals.


Assuntos
Dissuasores de Álcool/farmacologia , Córtex Cerebral/efeitos dos fármacos , Etanol/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Taurina/análogos & derivados , Taurina/farmacologia , Acamprosato , Animais , Animais Recém-Nascidos , Depressores do Sistema Nervoso Central/efeitos adversos , Córtex Cerebral/lesões , Córtex Cerebral/patologia , Cricetinae , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Ácido Ibotênico/toxicidade , Masculino , Gravidez
19.
Pediatr Res ; 57(2): 287-93, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15585688

RESUMO

Alcohol is one of the most common noxious substance to which fetuses are exposed. The aim of the study was to determine the effects of in utero alcohol exposure on excitotoxin-induced neuronal migration disorders. Female hamsters received alcohol (7%) for 3-5 mo or for the last 9-12 d of gestation. Alcohol diet was continued for 5 d during lactation in both groups. Drinking behavior was monitored. Peak plasma alcohol levels were 104+/-12 mg/dL and 225+/-6 mg/dL after 30 min for hamsters receiving an intragastric dose of 3 mL or 5 mL alcohol, respectively. At birth, pups received intrapallial injections ibotenic acid (1 ng, 100 ng, or 10 microg). Histology and N-methyl-D-aspartic acid (NMDA) receptor labeling by 3H-MK-801 in the pups cortices were studied. Short-term-alcohol-exposed pups had normal body and brain weights at birth, but their body growth was retarded postnatally. Ibotenic acid induced similar neuronal migration impairments in control and alcohol-exposed pups (nodular heterotopia in the white matter and/or deep cortical layers, subpial ectopia, and micro- or polymicrogyria). The size of lesions induced by 100 ng ibotenic acid was increased in alcohol-exposed pups; the 10 microg dose was lethal. The density of 3H-MK-801 binding sites was similar in the three groups, indicating that exacerbated ibotenic acid excitotoxicity in alcohol-exposed pups did not result from increased NMDA receptor density. This study shows that alcohol exposure at levels that do not induce neuron migration disorders is sufficient to enhance the effects of the hypoxia-ischemia mimicking effects of ibotenic acid.


Assuntos
Encéfalo/embriologia , Etanol/efeitos adversos , Ácido Ibotênico/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Intoxicação Alcoólica , Animais , Animais Recém-Nascidos , Sítios de Ligação , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Movimento Celular , Depressores do Sistema Nervoso Central/efeitos adversos , Cricetinae , Comportamento de Ingestão de Líquido , Feminino , Hipóxia , Ácido Ibotênico/metabolismo , Isquemia , Lactação , Mesocricetus , Neurônios/metabolismo , Gravidez , Prenhez , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
20.
J Neuropathol Exp Neurol ; 63(1): 53-63, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14748561

RESUMO

White matter (WM) lesions in preterm newborns may lead to cerebral palsy. To study WM lesions in a mouse model, we used intrapallial stereotactic injections of ibotenic acid, an N-methyl-D-aspartate receptor agonist. Previous studies support a contribution of tissue-type plasminogen activator (t-PA) to the brain lesions seen in various adult excitotoxic models. Therefore, we studied both 5-day-old (P5) wild-type mice and t-PA knock-out (t-PA-/-) mice. The ibotenic acid doses required to induce WM cysts were lower in the wild-type mice (EC50 < 0.01 microg/animal) than in the t-PA-/- mice (EC50 = 2.5 microg/animal) (p < 0.01), indicating the existence of t-PA-dependent and t-PA-independent mechanisms. Dose-dependent prolonged cyst growth occurred in the wild-type mice only. Early microglial activation and astrogliosis were similar in the wild-type and t-PA-/- mice. In adult mice (P45), demyelination occurred at the injection site in both groups but the astroglial scar was denser in the wild-type than in the t-PA-/- mice. These data support involvement of t-PA at several stages of WM lesion formation. Inactivation of t-PA might confer protection by prolonged hemostasis. The role of t-PA in cyst expansion suggests a new approach to the development of neuroprotective strategies in infants with developing WM lesions.


Assuntos
Encefalopatias/metabolismo , Encefalopatias/patologia , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Animais Recém-Nascidos , Encefalopatias/induzido quimicamente , Cistos/induzido quimicamente , Cistos/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Agonistas de Aminoácidos Excitatórios/administração & dosagem , Agonistas de Aminoácidos Excitatórios/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Ácido Ibotênico/administração & dosagem , Ácido Ibotênico/farmacologia , Imuno-Histoquímica , Injeções Intraventriculares , Camundongos , Camundongos Knockout , Neuroglia/patologia , Fatores de Tempo , Ativador de Plasminogênio Tecidual/genética
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