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1.
J Steroid Biochem Mol Biol ; 139: 201-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23583279

RESUMO

In this review we focused on steroid metabolomics in human fetuses and newborns and its role in the physiology and pathophysiology of human pregnancy and subsequent stages of human life, and on the physiological relevance of steroids influencing the nervous systems with regards to their concentrations in the fetus. Steroid profiling provides valuable data for the diagnostics of diseases related to altered steroidogenesis in the fetal and maternal compartments and placenta. We outlined a potential use of steroid metabolomics for the prediction of reproductive disorders, misbalance of hypothalamic-pituitary-adrenal axis, and impaired insulin sensitivity in subsequent stages of human life. A possible role of steroids exhibiting a non-genomic effect in the development of gestational diabetes and in the neuroprotection via negative modulation of AMPA/kainate receptors was also indicated. Increasing progesterone synthesis and catabolism, declining production of tocolytic 5ß-pregnane steroids, and rising activities of steroid sulfotransferases with the approaching term may be of importance in sustaining pregnancy. An increasing trend was demonstrated with advancing gestation toward the production of ketones (and 3ß-hydroxyl groups in the case of 3α-hydroxy-steroids) was demonstrated in the fetus on the expense of 3α-hydroxy-, 17ß-hydroxy-, and 20α-hydroxy-groups weakening in the sequence C17, C3, and C20. There was higher production of active progestogen but lower production of active estrogen and GABAergic steroids with the approaching term. Rising activities of placental CYP19A1 and oxidative isoforms of HSD17B, and of fetal CYP3A7 with advancing gestation may protect the fetus from hyperestrogenization. This article is part of a Special Issue entitled 'Pregnancy and Steroids'.


Assuntos
Encéfalo/metabolismo , Feto/metabolismo , Hormônios Esteroides Gonadais/fisiologia , Corticosteroides/fisiologia , Animais , Estrogênios/fisiologia , Feminino , Desenvolvimento Fetal , Humanos , Gravidez , Progestinas/fisiologia
2.
J Clin Endocrinol Metab ; 91(8): 3092-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16720657

RESUMO

BACKGROUND: Pregnanolone isomers (PI) with a hydroxy group in the 3alpha-position are neuroinhibitors operating via positive modulation of GABA(A) receptors. The 3beta-PI and sulfates of PI and pregnenolone exert the opposite effect. In addition to the brain's in situ synthesis, some circulating steroids can penetrate the blood-brain barrier. METHODS: To assess the physiological impact of peripheral endogenous neuroactive pregnanolone isomers and their polar conjugates in women, serum allopregnanolone (P3alpha5alpha), isopregnanolone (P3beta5alpha), pregnanolone (P3alpha5beta), epipregnanolone (P3beta5beta), pregnenolone, estradiol (including their polar conjugates), and additional steroids were measured in 16 women in the follicular and luteal phases of the menstrual cycle using gas chromatography/mass spectrometry and RIA for the analysis. Linear models and Spearman's correlations were used for data evaluation. RESULTS AND DISCUSSION: The levels of conjugated PI were from one to almost three orders of magnitude higher in comparison with the free steroids. The results indicate that a substantial proportion of the progesterone is metabolized in the sequence progesterone-->5beta-dihydroprogesterone-->P3alpha5beta-->conjugated P3alpha5beta. The sulfation of PI and particularly of P3alpha5beta moderates the levels of free PI and restrains estradiol biosynthesis via progesterone degradation. PI including the conjugates reflected changing progesterone formation during the menstrual cycle. In the follicular phase, the positive correlation with conjugated pregnenolone, the independence of progesterone, and the negative age relationships of PI indicate their adrenal origin. The dependence on progesterone and the independence of conjugated pregnenolone suggest a gonadal source of PI in the luteal phase. The neuroactivating PI prevailed over neuroinhibiting PI.


Assuntos
Pregnanolona/sangue , Adulto , Envelhecimento , Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Fase Folicular , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Isomerismo , Fase Luteal , Pregnanolona/química , Pregnenolona/sangue , Progesterona/sangue , Receptores de GABA-A/efeitos dos fármacos
3.
Alcohol Clin Exp Res ; 29(6): 1010-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15976527

RESUMO

BACKGROUND: Alcohol abuse is associated with menstrual irregularities related to the inhibition of progesterone secretion involved in regulation of the menstrual cycle. Reduced progesterone metabolites, including pregnanolone isomers (PIs), are efficient neuromodulators. The authors attempted to evaluate whether levels of PIs reflect impairment in progesterone biosynthesis in premenopausal women treated for alcohol addiction and whether alcohol detoxification therapy contributes to the restoration of their reproductive functions and psychosomatic stability by influencing steroid biosynthesis. METHODS: Serum allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one; P3alpha5alpha), pregnanolone (P3alpha5beta), isopregnanolone (P3beta5alpha), epipregnanolone (P3beta5beta), progesterone, pregnanolone sulfate (PregS), pregnanolone, and estradiol were measured in 20 women during therapy (at start, three days, 14 days, one month, and four months) by gas chromatography-mass spectrometry or radioimmunoassay. The results were evaluated by a linear mixed model for longitudinal data, with stage of the treatment and subject as categorical factors, phase of the menstrual cycle as a time-varying covariate, and age of the subject as a covariate and by regression in individual stages of the menstrual cycle. RESULTS: During detoxification treatment, progesterone increased in the luteal phase. P3alpha5alpha, P3beta5alpha, and P3beta5beta rose in both phases of the menstrual cycle. DISCUSSION: Given the similar mechanism in the effects of alcohol and steroids in activating gamma-aminobutyric acid A receptors, the restoration of progesterone and PIs during therapy could be explained by an adaptation to increasing requests for gamma-aminobutyric acid A-receptor activating substances owing to the cessation of alcohol intake or by the regeneration of progesterone formation. In conclusion, the reinstatement of progesterone, P3alpha5alpha, and P3beta5beta serum levels demonstrates the favorable effect of detoxification therapy on both reproductive functions and the psychosomatic stability of premenopausal women treated for alcohol addiction.


Assuntos
Alcoolismo/tratamento farmacológico , Pregnanolona/sangue , Pré-Menopausa/metabolismo , Progesterona/sangue , Adulto , Alcoolismo/reabilitação , Estradiol/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Modelos Lineares , Estudos Longitudinais , Ciclo Menstrual/sangue , Ciclo Menstrual/metabolismo , Pessoa de Meia-Idade , Pregnanolona/metabolismo , Pré-Menopausa/sangue , Progesterona/metabolismo , Radioimunoensaio , Análise de Regressão , Resultado do Tratamento
4.
Steroids ; 70(8): 515-24, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15894035

RESUMO

Long-term alcohol consumption results in menstrual irregularities due to the inhibition of progesterone secretion. Some progesterone metabolites, including three pregnanolone isomers (PI), abate, while pregnenolone sulfate (PregS) and dehydroepiandrosterone sulfate (DHEAS) increase, alcohol tolerance. The rationale of this study was to evaluate how the neuroactive steroids reflect the impaired progesterone formation in premenopausal women treated for alcohol addiction, and whether detoxification therapy could restore female reproductive functions and psychosomatic stability by reinstatement of the steroid biosynthesis. Accordingly, serum allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one (P3alpha5alpha)), pregnanolone (P3alpha5beta), isopregnanolone (P3beta5alpha) and epipregnanolone (P3beta5beta), progesterone, PregS, pregnenolone, 17alpha-hydroxy-pregnenolone (Preg17), 17alpha-hydroxy-progesterone (Prog17), DHEA, DHEAS, cortisol and estradiol were measured in 20 women during the therapy (start, 3 days, 14 days, 1 month, 4 months), and in 17 controls, using GC-MS or RIA and evaluated by age-adjusted ANCOVA with status and phase of the menstrual cycle (PMC) as factors, and status-PMC interaction. The patients exhibited depressed progesterone, Prog17, PI, and estradiol, a decreased progesterone/pregnenolone ratio, a decreased ratio of neuroinhibiting P3alpha5alpha to neuroactivating PregS, and an elevated PregS and PregS/pregnenolone ratio. The treatment mostly restored the indices. The reduction of neuroinhibiting pregnanolone isomers in the patients is primarily associated with the impairment in ovarian steroid biosynthesis. Nevertheless, changes in enzyme activities connected with the formation of PI and the influence of altered physiological requirements on the balance between endogenous neuroinhibiting and neuroactivating steroids are also likely. The reinstatement of serum estradiol, progesterone, and PI during the therapy demonstrates its favorable effect on both reproductive functions and the psychosomatic stability of the patients.


Assuntos
Alcoolismo/tratamento farmacológico , Pregnanolona/análogos & derivados , Pré-Menopausa/sangue , Pré-Menopausa/fisiologia , Esteroides/metabolismo , Desidroepiandrosterona/sangue , Desidroepiandrosterona/química , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/química , Sulfato de Desidroepiandrosterona/metabolismo , Estradiol/sangue , Estradiol/química , Estradiol/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Pregnanolona/sangue , Pregnanolona/química , Pregnanolona/metabolismo , Pregnenolona/sangue , Pregnenolona/química , Pregnenolona/metabolismo , Pré-Menopausa/efeitos dos fármacos , Progesterona/sangue , Progesterona/química , Progesterona/metabolismo , Radioimunoensaio , Estereoisomerismo , Esteroides/sangue , Esteroides/química , Fatores de Tempo
5.
J Steroid Biochem Mol Biol ; 96(2): 187-200, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15908198

RESUMO

7-Hydroxy-metabolites of dehydroepiandrosterone (DHEA) and 3beta,17beta-androstenediol (AD) possess immunomodulatory and neuroprotective properties; therefore, the measurement of these steroids in patients with autoimmune diseases or disturbances in the CNS may be of interest. A gas chromatography-mass spectrometry (GC-MS) method for the determination of 7-hydroxy-metabolites of pregnenolone, DHEA, AD, and testosterone including the parent steroids was applied to serum samples from 12 adult men (27-66 years), 13 male adolescents (13-20 years), 5 boys (6-10 years), 15 women in the follicular phase of the menstrual cycle (22-45 years), 17 women in the luteal phase (22-45 years), and 4 girls (6-10 years). The steroids were age and sex dependent, but independent of the menstrual cycle. The ratio of the 7alpha-hydroxy-metabolites to their parent steroids were age dependent, exhibiting an increasing trend (p < 0.0001, ANOVA) from pregnenolone (5%) to AD (20%). The ratio of 7beta- to 7alpha-metabolites ranged from 0.6 to 1. These results are consistent with models suggesting 7alpha-hydroxylation of the parent steroid, conversion to a 7-oxo-steroid and finally to the 7beta-hydroxylated-metabolite. Partial correlations suggested that 7-hydroxylation might reduce the concentration of circulating androgens. Despite the three times lower concentration of AD-metabolites, their antiglucocorticoid, immunomodulatory, and neuroprotective effects may be comparable to that of DHEA based on their reported greater biological activity.


Assuntos
Androstenodiol/análogos & derivados , Androstenodiol/sangue , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Pregnenolona/análogos & derivados , Pregnenolona/sangue , Testosterona/análogos & derivados , Testosterona/sangue , Adolescente , Adulto , Criança , Feminino , Fase Folicular , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxilação , Masculino , Valores de Referência
6.
J Clin Endocrinol Metab ; 90(1): 395-403, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15486056

RESUMO

The pregnanolone isomers (PI) allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one), pregnanolone (3alpha-hydroxy-5beta-pregnan-20-one), isopregnanolone (3beta-hydroxy-5alpha-pregnan-20-one), epipregnanolone (3beta-hydroxy-5beta-pregnan-20-one), progesterone, and estradiol were measured in 138 pregnant women. The sampling was carried out from the first through the 10th month of pregnancy. Gas chromatography-mass spectrometry analysis and RIA were used for the measurement of steroid levels. The ratios of individual PI were similar to those found previously around parturition: about 25:10:7:1 for allopregnanolone, pregnanolone, isopregnanolone, and epipregnanolone, respectively. All the PI showed a significant increase during pregnancy, which was more pronounced in the 3alpha-steroids. The results indicated changing ratios between 3alpha- and 3beta-PI and between 5alpha- and 5beta-PI throughout pregnancy. The constant allopregnanolone/isopregnanolone ratio found through pregnancy weakened the hypothesis of the role of isopregnanolone in the onset of parturition. The ratio of estradiol (stimulating uterine activity) to 5alpha-PI and epipregnanolone exhibited significant changes during pregnancy in favor of estradiol up to the sixth or seventh month, in contrast to the constant estradiol/pregnanolone ratio. A pregnancy-stabilizing role of pregnanolone, counterbalancing the stimulating effect of estradiol on the onset of parturition, was suggested.


Assuntos
Gravidez/sangue , Pregnanolona/sangue , Estradiol/sangue , Feminino , Idade Gestacional , Humanos , Isomerismo , Trabalho de Parto/sangue , Progesterona/sangue
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