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1.
Physiol Res ; 55(1): 49-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-15857167

RESUMO

Dehydroepiandrosterone may influence thyroid function. Its metabolite, 7-oxo-dehydroepiandrosterone, a precursor of immunomodulatory 7-hydroxylated metabolites and thermogenic agent, belongs to candidates of steroid replacement therapy. The question was addressed whether its application does influence laboratory parameters of thyroid function. 7-Oxo-dehydroepiandrosterone in the form of emulgel, 25 mg/day, was applied transdermally to 21 healthy men for 8 consecutive days. Morning blood was collected before the treatment (Day 0, Stage 1), during treatment (Day 5, Stage 2), on the first day after the last administration (Day 9, Stage 3), one week (Day 16, Stage 4), and 9 weeks (Day 72, Stage 5) after treatment termination. The levels of thyrotropin, free thyroxine and triiodothyronine, dehydroepiandrosterone, its sulfate and its 7-hydroxyepimers were measured. The changes were evaluated by analysis of variance and correlation analysis. During treatment a significant rise of 7beta-hydroxy-dehydroepiandrosterone was observed, which persisted 1 week after treatment termination. No changes were observed in dehydroepiandrosterone and its sulfate. Though a slight but significant rise of TSH and of both thyroid hormones occurred during treatment, its levels soon returned to the basal values. It was concluded that treatment of 7-oxo-dehydroepiandrosterone affects the thyroid parameters only temporarily and that it provides a considerable persistent amount of 7beta-hydroxy-dehydroepiandrosterone.


Assuntos
Desidroepiandrosterona/análogos & derivados , Glândula Tireoide/efeitos dos fármacos , Administração Cutânea , Adulto , Idoso , Análise de Variância , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/sangue , Desidroepiandrosterona/farmacologia , Géis , Experimentação Humana , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Glândula Tireoide/fisiologia , Hormônios Tireóideos/sangue , Fatores de Tempo
2.
Physiol Res ; 54(2): 151-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15544418

RESUMO

The influence of steroid hormones on plasma lipids and lipoproteins was confirmed by many studies. On the other hand, the effect of plasma lipids on metabolism of steroid hormones has so far not been examined. The objective of this research project was to determine (1) the levels of cortisol, testosterone, estradiol, dehydroepiandrosterone (DHEA), its sulfate (DHEAS), 7-hydroxylated DHEA, and SHBG in men suffering from mixed hyperlipidemia (HPL) (n=23, age 46.1+/-7.9 years) in comparison with healthy male volunteers (n=17, age 45.1+/-15.6 years); (2) whether therapy with fenofibrate influences the levels of the above mentioned steroids and SHBG; (3) what are the correlations between lipids and steroids in healthy males and HPL patients before and after therapy. Compared to controls, untreated patients had significantly higher estradiol and free testosterone index (IFT) levels (p<0.0003 and p<0.02, respectively) and significantly lower SHBG (p<0.02). Due to fenofibrate therapy, a significant decrease of TC, TG, and DHEA levels occurred (mean decrease: 14 %, 52 % and 21 %, respectively). Triglycerides correlated negatively with testosterone and SHBG in healthy subjects. HDL-C correlated positively and consequently, atherogenic index correlated negatively with 7-hydroxylated epimers of DHEA in treated patients. This is the first study dealing with the influence of fenofibrate administration on the steroid levels. Taking together, the most important is the finding of decrease DHEA levels after fenofibrate therapy. It could be explained, at least in part, by the effect of the fenofibrateon on the biosynthesis of DHEA and its regulation.


Assuntos
Desidroepiandrosterona/sangue , Fenofibrato/uso terapêutico , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
3.
Physiol Res ; 52(2): 211-21, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12678664

RESUMO

The levels of four pregnanolone isomers and their polar conjugates and pregnenolone sulfate were measured in the plasma of 13 and 7 women at delivery with subarachnoidal and epidural analgesia, respectively, and in corresponding samples of umbilical plasma using a simple quadrupole GC/MS system with electron impact ionization (pregnenolone isomers), RIA following HPLC separation (pregnenolone) and specific RIA (pregnanolone sulfate). The concentration of epipregnanolone (3beta-hydroxy-5beta-pregnan-20-one) in both maternal and umbilical plasma was much lower than that of other pregnanolone isomers. The levels of 3beta-hydroxy-pregnanolone isomers were significantly higher in the umbilical plasma than in the maternal, while the differences in 3alpha-hydroxy-isomers were insignificant. The differences in conjugates were insignificant with the exception of allopregnanolone, the levels of which were lower in umbilical plasma. In all the pregnanolone isomers, a significantly lower conjugated/unconjugated steroid ratio was found in the umbilical plasma than in the maternal plasma. In addition, time profiles of the steroids were measured around parturition and in the postpartum period in the maternal serum. Similarly, the levels of polar conjugates of all pregnanolone isomers were followed during parturition. Changes in concentrations of free steroids exhibited a similar pattern, with a fall primarily within the first hour after delivery. The decrease in conjugated steroids was shifted to the interval within the first hour and first day after delivery, and the changes were more pronounced. The time profiles of the conjugated/free steroid ratio exhibited a significant decrease within the first hour and the first day after delivery in all of the isomers investigated. A decrease was also observed in the ratio of 3alpha/3beta-isomers and 5alpha/5beta-isomers around parturition. The possible physiological consequences of the findings are indicated.


Assuntos
Sangue Fetal/metabolismo , Trabalho de Parto/sangue , Período Pós-Parto/sangue , Pregnanolona/sangue , Pregnanolona/classificação , Feminino , Humanos , Isomerismo , Gravidez , Pregnanolona/química , Pregnanolona/metabolismo
4.
Physiol Res ; 52(1): 53-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12625807

RESUMO

Obesity in children is accompanied by increased circulating leptin concentrations. Girls have higher leptin concentrations than boys. The aim of our study was to compare serum leptin levels before and after a five-week weight reduction program and to study the relationship of leptin levels, serum total cholesterol, and androgens (testosterone, dehydroepiandrosterone, dehydroepiandrosterone sulphate) in 33 obese boys (age: 12.7+/-1.97 years, BMI: 30.46+/-4.54) and 66 obese girls (age: 12.7+/-2.51 years, BMI: 29.31+/-4.62). We found that serum leptin concentrations in obese children were significantly decreased after a weight reduction program (before 20.79+/-9.61 ng/ml, after 13.50+/-8.65 ng/ml in girls; before 12.25+/-10.09 ng/ml and after 5.18+/-3.56 ng/ml in boys, p<0.0001 in both genders). Leptin levels correlated positively with the body mass index before and after weight reduction. There was a positive association in obese boys and a negative one in obese girls between leptin levels and the WHR (waist to hip circumference ratio). Serum leptin also shows a strong relationship to fat distribution (p=0.02 in boys, p<0.0001 in girls). No significant correlation was found between leptin concentrations and total cholesterol or androgens. We confirmed that leptin is a sensitive parameter of body composition and weight reduction in obese children.


Assuntos
Androgênios/sangue , Leptina/sangue , Obesidade/sangue , Caracteres Sexuais , Redução de Peso , Adolescente , Composição Corporal , Índice de Massa Corporal , Criança , Colesterol/sangue , Feminino , Humanos , Masculino
5.
J Steroid Biochem Mol Biol ; 82(2-3): 241-50, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12477491

RESUMO

Five 3beta-hydroxy-5-ene steroids involved in the metabolic route from pregnenolone sulfate to dehydroepiandrosterone and its sulfate, of which three are known allosteric modulators of neurotransmitter receptors, were monitored in the serum of 20 women around parturition. In addition, their levels in maternal and umbilical serum were compared at delivery. On the basis of these data, a scheme of steroid biosynthesis in maternal organism during the critical stages around parturition is proposed. In maternal serum, all the steroids except dehydroepiandrosterone sulfate decreased during labor and even first day after delivery, although their changes were less distinct the more distant from pregnenolone sulfate (PregS) in the metabolic pathway. Calculation of product/immediate precursor ratios in maternal serum over all stages around parturition enabled identification of the respective changes in the activities of the relevant enzymes. The ratio of 17-hydroxypregnenolone/pregnenolone did not change significantly, while that of dehydroepiandrosterone/17-hydroxypregnenolone grew, indicating increased C17,20 side chain cleavage on the account of C17-hydroxylation both catalyzed by C17-hydroxylase-C17,20-lyase. As was shown by factor analysis, the changes in the maternal steroids were associated with a single common factor, which strongly correlated with all the steroids except dehydroepiandrosterone sulfate. The lack of change in the pregnenolone sulfate/pregnenolone ratio and a marked increase of the ratio dehydroepiandrosterone sulfate to unconjugated dehydroepiandrosterone indicate a different means of formation of both steroid sulfates. On the basis of these data, a scheme of steroid biosynthesis in maternal organism during the critical stages around parturition is proposed.


Assuntos
Sangue Fetal/química , Parto/metabolismo , Período Pós-Parto/metabolismo , Esteroides/sangue , Feminino , Feto/fisiologia , Humanos , Trabalho de Parto/metabolismo , Gravidez , Estatística como Assunto , Esteroides/química , Fatores de Tempo
6.
J Steroid Biochem Mol Biol ; 78(1): 51-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11530284

RESUMO

Time profiles of the pregnanolone isomers epipregnanolone (3 beta-hydroxy-5 beta-pregnan-20-one), allopregnanolone (3 alpha-hydroxy-5 alpha-pregnan-20-one), pregnanolone (3 alpha-hydroxy-5 beta-pregnan-20-one), and isopregnanolone (3 beta-hydroxy-5 alpha-pregnan-20-one) were measured around parturition and in the postpartum period in the serum of 13 and three women with subarachnoidal and epidural analgesia, respectively. In addition, the levels of polar conjugates of all pregnanolone isomers were followed during parturition. GC/MS analysis was used for the measurement of steroid levels. Changes in concentrations of free steroids exhibited a similar pattern, with a fall primarily within the first hour after delivery. The decrease in conjugated steroids was shifted to the interval within the first hour and first day after delivery, and the changes were more pronounced. The time profile of the conjugated/free steroid ratio exhibited a significant decrease within the first hour and the first day after delivery in all of the isomers investigated. A decrease was also observed in the ratio of 3 alpha/3 beta-isomers and 5 alpha/5 beta-isomers around parturition. The possible physiological consequences of the findings are indicated.


Assuntos
Trabalho de Parto/sangue , Período Pós-Parto/sangue , Pregnanolona/sangue , Adulto , Analgésicos/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Gravidez , Pregnanolona/análogos & derivados , Pregnanolona/química , Estereoisomerismo , Esteroides/sangue , Fatores de Tempo
7.
Eur J Endocrinol ; 144(6): 619-28, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375796

RESUMO

OBJECTIVE: To evaluate adrenal and ovarian steroidogenesis before and after long-term treatment with metformin in women with polycystic ovary syndrome (PCOS). DESIGN AND METHODS: Twenty-four women with PCOS were evaluated before and after treatment (27+/-4 weeks) with metformin (1000 mg/day) using adrenocorticotrophin (ACTH), GnRH analogue and oral glucose tolerance (oGTT) tests. For statistical evaluation, ANOVA and Wilcoxon's test were used. RESULTS: In 58% of the women a significant improvement in menstrual cyclicity was observed. No significant change in basal steroid levels was found. After ACTH stimulation, a significant decrease in the activity of 3 beta-hydroxysteroid dehydrogenase in C(21) steroids (P<0.05) and in 17 beta-hydroxysteroid dehydrogenase (P<0.01) was observed, as was an increase in the activity of C17,20-lyase in the Delta(4) pathway (P<0.01). A significant growth in the dehydroepiandrosterone (DHEA)/DHEA-sulfate ratio (P<0.05) was detected. With regard to ovarian steroidogenesis, a significant decrease in the stimulated levels of testosterone (P<0.05), index of free testosterone (P<0.01), LH (P<0.05) and oestradiol (P<0.01), and an increase in the levels of 17-hydroxypregnenolone (P<0.05) were detected. In the indices of ovarian enzyme activities, we observed a significant decrease in 3 beta-hydroxysteroid dehydrogenase in C21 steroids (P<0.01), in C17,20-lyase in the Delta 5 pathway (P<0.01), in 17 beta-hydroxysteroid dehydrogenase (P<0.05) and in aromatase. In glucose metabolism, a tendency towards reduction in the homeostasis model assessment (HOMA)-R (for insulin resistance) and HOMA-F (for beta cell function) was detected. In addition, an increase in the levels of C peptide during oGTT was observed (P<0.01). CONCLUSIONS: Long-term metformin treatment reduced various steroid enzymatic activities both in the ovary and the adrenal glands, without apparent changes in basal steroid levels and in insulin sensitivity.


Assuntos
Glândulas Suprarrenais/metabolismo , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Esteroides/biossíntese , Hormônio Adrenocorticotrópico , Adulto , Feminino , Teste de Tolerância a Glucose , Hormônio Liberador de Gonadotropina , Homeostase/efeitos dos fármacos , Humanos , Resistência à Insulina
8.
Physiol Res ; 50(1): 9-18, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11300231

RESUMO

The aim of this study was to investigate the effect of 7-oxo-DHEA (dehydroepiandrosterone) on the serum levels of steroid sexual hormones, gonadotropins, lipids and lipoproteins in men. 7-oxo-DHEA was applied onto the skin as a gel to 10 volunteers aged 27 to 72 years for 5 consecutive days. The single dose contained 25 mg 7-oxo-DHEA. Serum concentrations of testosterone, estradiol, cortisol, androstenedione, luteinizing hormone (LH), follicle-stimulating hormone (FSH), sex hormone binding globulin (SHBG), total cholesterol, HDL- and LDL-cholesterol, triglycerides, apolipoprotein A-I and B and lipoprotein(a) were measured before the beginning and shortly after the end of the steroid application. After the treatment, we noted the following significant changes: a decline of testosterone and estradiol levels, increase of LH, HDL-cholesterol and apolipoprotein A-I levels. The decrease of total cholesterol levels was of the borderline significance. A slight but significant increase was found in apolipoprotein B and lipoprotein(a). The most expressive was the fall of the atherogenic index. We suggest that the gel containing 7-oxo-DHEA might be a suitable drug for improving the composition of the steroid and lipid parameters in elderly men.


Assuntos
Desidroepiandrosterona/administração & dosagem , Hormônios Esteroides Gonadais/sangue , Gonadotropinas/sangue , Lipídeos/sangue , Administração Cutânea , Adulto , Idoso , Androstenodiona/sangue , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Desidroepiandrosterona/farmacologia , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hidrocortisona/sangue , Lipoproteína(a)/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Triglicerídeos/sangue
9.
Endocr Regul ; 35(1): 17-24, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11308992

RESUMO

OBJECTIVE: In girls with Turner's syndrome a positive effect of growth hormone (GH) therapy on statutal growth has been well documented, in spite of the fact that the levels of GH and IGF-I in these patients are usually within the normal range. It is known that plasma levels of sex hormone-binding globulin (SHBG) are negatively associated with growth hormone (GH) and with [GF-I. Limited data on SHBG levels in these patients and only scarce reports on other than gonadal steroids in these patients are available so far. The major aim of this study was to find out whether SHBG does respond to GH treatment. METHODS: Plasma levels of SHBG, estradiol, progesterone, testosterone and the adrenal steroids and their precursors, namely cortisol, 17alpha-hydroxyprogesterone, androstenedione, dehydroepiandrosterone and its sulfate were determined in 65 patients aged 2-23 years with Turner's syndrome. The patients were divided into 4 groups according to their actual treatment (untreated, sex steroids only, GH only, GH and sex steroids) and the differences between the groups were evaluated. With respect to dependence of SHBG and of steroids studied on age (with exception of cortisol), their values were expressed as per cents of medians of the physiological values. RESULTS: As expected, low levels of sex steroids were found. As to the adrenal steroids, in general, their average levels were lower than in healthy subjects but still within the physiological limits. With one exception (androstenedione), no significant differences were found between the groups. The levels of cortisol were undistinguishable from healthy subjects. Absolute as well as relative SHBG levels in untreated group and in the group treated with estrogens were normal or even lower than those reported for normal subjects of the same chronological age. Significantly reduced absolute as well as relative SHBG levels in comparison to all other groups were found in GH treated children. CONCLUSION: The results indicate that SHBG may serve as a sensitive biochemical marker of the response to the GH administration.


Assuntos
Biomarcadores/sangue , Hormônio do Crescimento Humano/uso terapêutico , Globulina de Ligação a Hormônio Sexual/análise , Síndrome de Turner/tratamento farmacológico , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Corticosteroides/sangue , Adulto , Androstenodiona/sangue , Criança , Pré-Escolar , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Estrogênios/administração & dosagem , Estrogênios/uso terapêutico , Feminino , Humanos , Ensaio Imunorradiométrico , Fator de Crescimento Insulin-Like I/análise , Acetato de Medroxiprogesterona/administração & dosagem , Acetato de Medroxiprogesterona/uso terapêutico , Progesterona/sangue , Testosterona/sangue , Síndrome de Turner/sangue
10.
Cas Lek Cesk ; 140(22): 688-94, 2001 Nov 08.
Artigo em Tcheco | MEDLINE | ID: mdl-11789058

RESUMO

BACKGROUND: Insulin resistance is probably the key factor in the pathogenesis of polycystic ovary syndrome, and thus insulin sensitization can be a beneficial treatment. We tried to investigate effects of long-term therapy with metformin in polycystic ovary syndrome on steroid levels, ovarian steroidogenesis and on insulin resistance and secretion. We also tried to find predictors of the successful therapy (in terms of improvement of menstrual cyclicity). METHODS AND RESULTS: 24 oligo/amenorhoeic women with polycystic ovary syndrome were included into the study. Basal blood samples were taken for the determination of testosterone, estradiol, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone-sulphate, 17OH progesterone, 17OH pregnenonole, sex-hormone binding globulin and cortisol. Gonadoliberin (GnRH) analogue test was performed with estimation of the same steroids and LH. Oral glucose tolerance test was done with dextrose, and with estimation of glucose, insulin, and C peptide. HOMA model assessment was used for calculation of insulin resistance and insulin secretion. All examinations were done before and after 27 +/- 4 weeks (average +/- standard deviation) of therapy with metformin 1000 mg/day. Significant improvement in menstrual cyclicity was observed in 58% of women. No significant change in basal steroid levels was found. A trend towards decline in insulin resistance and secretion was detected. Significant decrease in the mean stimulated testosterone level (from 1.74 to 1.54 nmol/l, 95% CI 1.42-2.08 and 1.21-1.87; p < 0.05), 17OH progesterone level (from 3.32 to 2.37, 95% CI 1.42-2.08 and 1.21-1.87; p < 0.05), LH (from 9.1 to 4.8 IU/l, 95% CI 6.4-12.8 and 3.4-6.8; p < 0.05), and estradiol level (from 0.91 to 0.43 nmol/l, 95% CI 0.69-1.19 and 0.38-0.65; p < 0.01) were detected. The best prediction of the improvement in menstrual cyclicity after metformin was achieved with the combination of basal 17OH progesterone, androstendione, testosterone and SHBG. This model correctly classified 86.7% of subjects. CONCLUSIONS: Long-term therapy with metformin led to the improvement in menstrual cyclicity, without significant change in basal steroid levels or parameters of insulin resistance.


Assuntos
Androgênios/sangue , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , 17-alfa-Hidroxipregnenolona , 17-alfa-Hidroxiprogesterona , Adulto , Feminino , Teste de Tolerância a Glucose , Humanos , Ciclo Menstrual/efeitos dos fármacos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia
11.
Exp Clin Endocrinol Diabetes ; 108(7): 455-62, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11083066

RESUMO

Polycystic ovary syndrome (PCOS) is connected with insulin resistance (IR), and often with the hypersecretion of adrenal androgens. Mutual relationships between IR and adrenal and ovarian steroidogenesis were investigated in the group of 19 oligo/amenorhoeic women with PCOS. The age and body mass index (BMI) of the patients were 21+/-4.7 years and 26.4+/-5 kg/m2 (average+/-SD), respectively. All underwent a 60-minute adrenocorticotrophic hormone (ACTH) stimulation test, a gonadoliberin analogue (GnRHa) test with buserelin and an oral glucose tolerance test (oGTT) in the early follicular phase of the menstrual cycle. When absolute stimulated steroid levels after GnRHa were studied, a significant positive correlation between DHEA and area under curve during oGTT for C peptide (AUC-CP) (r=0.477, p= 0.039) and a borderline negative correlation (r=-0.404, p= 0.087) between AUC-CP and 17-OH progesterone, were found. Considering steroid values after ACTH, a significant positive correlation of IR index was found only with 17-OH-progesterone (r=0.499, p= 0.03). When stimulated enzymatic activities (expressed as product/ precursor ratios) were analyzed using factor analysis, a positive relationship between IR and ovarian C17,20-lyase in both delta4 and delta5 pathway was revealed. On the other hand, no relationship was confirmed between IR and enzymatic activities in the adrenals. The authors conclude that insulin resistance and/or hyperinsulinemia is probably not the primary factor responsible for the exaggerated adrenal androgen secretion found in a great number of patients with PCOS.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Glândulas Suprarrenais/enzimologia , Resistência à Insulina , Ovário/enzimologia , Síndrome do Ovário Policístico/fisiopatologia , Esteroide 17-alfa-Hidroxilase/metabolismo , 17-alfa-Hidroxiprogesterona/sangue , Hormônio Adrenocorticotrópico , Adulto , Androgênios/sangue , Glicemia/metabolismo , Peptídeo C/sangue , Desidroepiandrosterona/sangue , Análise Fatorial , Feminino , Teste de Tolerância a Glucose , Humanos , Hidrocortisona/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/enzimologia , Valores de Referência
12.
Physiol Res ; 49 Suppl 1: S43-56, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10984071

RESUMO

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS), the major androgens secreted by human adrenal glands, were suggested to play a protective role in the pathogenesis of atherosclerosis and coronary heart disease. On the basis of a critical review of all existing studies we concluded that 1) there is no evidence of a protective role of DHEA and DHEAS in women, and 2) men with low plasma DHEA and DHEAS levels can be considered as beings at risk of developing a fatal cardiovascular event. These androgens can interfere with atherogenic process by several mechanisms. They influence enzymes such as glucoso-6-phosphate dehydrogenase, which can modify the lipid spectrum. Furthermore, they can inhibit human platelet aggregation, enhance fibrinolysis, slow down cell proliferation and reduce plasma levels of plasminogen activator inhibitor type 1 and tissue plasminogen activator antigen. We suggest that all these DHEA(S) actions are dependent on sex hormone metabolic pathways. There are still insufficient data to advise DHEA supplementation in elderly men, but this type of hormone replacement therapy merits further studies.


Assuntos
Doença das Coronárias/epidemiologia , Doença das Coronárias/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Desidroepiandrosterona/metabolismo , Animais , Doença das Coronárias/tratamento farmacológico , Estudos Transversais , Desidroepiandrosterona/sangue , Desidroepiandrosterona/uso terapêutico , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/uso terapêutico , Feminino , Terapia de Reposição Hormonal , Humanos , Masculino , Estudos Prospectivos , Caracteres Sexuais
13.
Physiol Res ; 49(6): 685-93, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11252535

RESUMO

In order to ascertain the kinetics of absorption and metabolism of transdermally administered dehydroepiandrosterone (DHEA), 10 men 29-72 years old (mean 52.4+/-14.5) received 50 mg DHEA/day in a gel applied onto the skin of the abdomen for 5 consecutive days. The objective was to establish the extent to which DHEA influences the levels of gonadotropins, sex hormone-binding globulin and lipids. It was found that DHEA is well absorbed and rapidly metabolized to its sulfate (DHEAS), androstenedione, and consequently to testosterone and estradiol. The DHEA levels that markedly increased after the first doses gradually declined already during the application, and this decline proceeded even after it was discontinued, reaching levels significantly lower than the original ones. On the other hand, the levels of DHEA metabolites (with the exception of DHEAS) rose during the application and reached values significantly higher than the basal ones within 5 weeks. This effect was accompanied by significantly decreased levels of LH. The serum levels of lipids, namely of cholesterol (both HDL and LDL cholesterol), triglycerides, apolipoproteins A-I and B and lipoprotein(a) after DHEA application were not changed significantly, and the atherogenic index (AI) remained unaltered. However, some correlations between hormones and lipids were found. Negative correlations concerned the following indices: DHEA/Lp(a); DHEAS/cholesterol; DHEA, DHEAS, testosterone/TG; testosterone/AI. On the other hand, LH, FSH/cholesterol, FSH, SHBG/LDL cholesterol, FSH/Apo B, Lp(a) correlated positively. It can be concluded that transdermal short-time application of DHEA results in a decrease of endogenous DHEA after finishing the treatment, with a parallel marked increase in the levels of sex hormones. Using this application protocol, exogenous DHEA neither altered the lipid spectrum, nor did it influence the atherogenic index.


Assuntos
Desidroepiandrosterona/administração & dosagem , Gonadotropinas Hipofisárias/sangue , Lipídeos/sangue , Esteroides/sangue , Administração Cutânea , Adulto , Idoso , Androstenodiona/sangue , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Desidroepiandrosterona/sangue , Desidroepiandrosterona/farmacocinética , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Géis , Humanos , Cinética , Lipoproteína(a)/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Testosterona/sangue , Triglicerídeos/sangue
14.
J Steroid Biochem Mol Biol ; 75(4-5): 237-44, 2000 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11282277

RESUMO

A rapid method for the identification and measurement of four pregnanolone isomers and their polar conjugates in human plasma was developed using a simple quadrupole GC/MS system with electron impact ionization. Steroid levels were measured in the plasma of 13 and three women at delivery with subarachnoidal and epidural analgesia, respectively, and in corresponding samples of umbilical plasma. A good correlation (r=0.94, P<0.001, n=8) was found between the allopregnanolone in maternal plasma determined by GC/MS and that measured by RIA. Epipregnanolone (3beta-hydroxy-5beta-pregnan-20-one) was identified and measured for the first time in human plasma; its concentration in both maternal and umbilical plasma was much lower than that of other pregnanolone isomers. The levels of 3beta-hydroxy-pregnanolone isomers were significantly higher in the umbilical plasma than in the maternal plasma, while the differences in 3alpha-hydroxy-isomers were insignificant. The differences in conjugates were insignificant except in the case of allopregnanolone, the levels of which were lower in umbilical plasma. In all of the pregnanolone isomers, a significantly lower conjugated/unconjugated steroid ratio was found in the umbilical plasma than in the maternal plasma. The possible role of the sulfatation of pregnanolone isomers around parturition is discussed.


Assuntos
Sangue Fetal/metabolismo , Trabalho de Parto/sangue , Período Pós-Parto/sangue , Pregnanolona/sangue , Adulto , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Recém-Nascido , Gravidez , Pregnanolona/química , Estereoisomerismo
15.
Cas Lek Cesk ; 139(24): 772-5, 2000 Dec 06.
Artigo em Tcheco | MEDLINE | ID: mdl-11262916

RESUMO

BACKGROUND: Relationship between dehydroepiandrosterone (DHEA), its sulphate (DHEAS) and various components of metabolic syndrome X have been recently discussed in several papers. Originally only DHEA or DHEAS have been considered to be responsible for all of the effects. At present mainly DHEA hydroxyderivatives (particularly 7-hydroxyisometers) are assumed to be responsible for those effects. METHODS AND RESULTS: 68 obese subjects (28 males) aged 42.6 +/- 11.1 years, with average BMI 35.7 +/- 11.6 kg/m2 were examined. Relationship between 7-alpha and 7-beta-(OH)-DHEA and various components of metabolic syndrome X have been followed in a pilot epidemiological study. Fluctuations of the hydroxyderivates level during one-day starvation test were investigated in a group of 11 obese females and compared with that of the control group (12 lean subjects with BMI 23.1 +/- 2.4 kg/m2). From the view of the metabolic syndrome X, the negative correlation between the serum levels of 7-beta-(OH)-DHEA and insulinemia (r = -0.28; p = 0.23), glycemia (r = -0.48; p < 0.001), serum level of uric acid (r = -0.35; p = 0.02) and opposite the positive correlation between the serum level of HDL-cholesterol (r = 0.42; p < 0.01) should be pointed out. The negative correlation between 7-alpha-(OH)-DHEA and age and BMI was noticed (correlation for 7-beta-(OH)-DHEA was similar). No other statistically significant correlation was found among the other monitored parameters. In 11 obese females the dynamic changes of the above-mentioned DHEA hydroxyderivatives during one-day starvation test were monitored. Changes were compared with the control group (12 lean females). Significant increases in DHEAS, 7-beta-(OH)-DHEA, and sex hormone binding globulin (SHBG) levels were observed during this test. Significant differences in dynamic changes (before and after the test) between obese and lean group have been found only in DHEAS and SHBG. CONCLUSION: We suppose that 7-beta-(OH)-DHEA (more than 7-alpha-(OH)-DHEA) is specifically related to the metabolic syndrome X and that its claimed anti-glucocorticoid effect in the immune response can play some role in its metabolic effects.


Assuntos
Desidroepiandrosterona/sangue , Resistência à Insulina , Obesidade/sangue , Inanição/sangue , Adulto , Desidroepiandrosterona/análogos & derivados , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Steroids ; 64(5): 341-55, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10406484

RESUMO

Polyclonal antiserum against 3beta,17alpha-dihydroxypregn-5-en-20-one-19-O-(carboxymethyl )-oxime bovine serum albumin (17alpha-hydroxypregnenolone-19-CMO:BSA), was raised in rabbits. Its main structural determinants were the substituents on D-ring as demonstrated by its 107% cross-reaction with 17alpha-hydroxyprogesterone. This unspecificity was almost completely eliminated by addition of the excess of the cross-reactant directly to the analytical system. The contribution of the cross-reactant from the sample in such a system became negligible due to saturation of the populations of polyclonal antibodies recognizing the analyte as well as the cross-reactant. The possible interference of 17alpha-hydroxypregnenolone-3-sulfate was avoided by inserting ether extraction. The analytical system appeared to be stable to differences in cross-reactant concentrations even in samples from patients with pathologically elevated serum levels of 17alpha-hydroxyprogesterone. The radioimmunoassay was compared with the system using the unspecific antiserum alone, but after separation of the cross-reactants by HPLC. As demonstrated by parallel measurement of 125 samples of human plasma from both sexes and various ages either before and/or after adrenocorticotropin stimulation and 17 samples with elevated basal of human plasma 17alpha-hydroxyprogesterone levels, an excellent correlation was achieved between both methods. The method, based on a simple addition of the cross-reactant, avoids the time-consuming chromatographic separation and, in comparison with the other approaches for improving the specificity of polyclonal antisera, is efficient and rapid. Mathematical analysis of the relations in equilibrium demonstrates that such a simple approach is an efficient way for improvement of immunoassay specificity using some polyclonal antisera.


Assuntos
17-alfa-Hidroxipregnenolona/sangue , Radioimunoensaio/métodos , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Controle de Qualidade , Sensibilidade e Especificidade , Trítio
17.
Clin Chem Lab Med ; 37(4): 439-47, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10369116

RESUMO

17-Hydroxypregnenolone (3beta,17alpha-dihydroxypregn-5-en-20-one) and pregnenolone (3beta-hydroxypregn-5-en-20-one) were determined by radioimmunoassay following HPLC separation in serum of healthy subjects of both sexes from 2 to 66 years old (29 girls, 85 women, 30 boys, 89 men). The effects of age and sex on the levels of both steroids were investigated and the upper limits of normal in age groups were determined. The 17-hydroxypregnenolone levels as a function of age were characterized by a statistically significant maximum at the age of 18 and 20 years followed by a local minimum at the age of 39 and 37 years and by a statistically insignificant local maximum at the age of 55 and 49 years in men and women, respectively. Pregnenolone age-dependence was similar and the statistically significant maximum was reached at the age of 17 and 16 years, the local minimum occurred at the age of 37 and 38 years and the second, statistically insignificant, local maximum at the age of 48 and 47 years in men and women, respectively. Both 17-hydroxypregnenolone and pregnenolone in both sexes exhibited similarly shaped peaks with age. Both peaks of the polynomial fit in 17-hydroxypregnenolone were more pronounced in men than in women (13.0 and 9.20 nmol/l in the first peak; 7.72 and 4.78 in the second peak respectively). The situation with pregnenolone was the opposite. Both peaks of the polynomial fit in pregnenolone were lower in men than in women (2.29 and 3.21 nmol/l in the first peak; 0.92 and 1.78 in the second peak, respectively). The higher serum levels of pregnenolone at puberty and during fertile age and their wider variance in comparison with men could, be explained by the different gonadal steroidogenesis depending on the menstrual cycle, where the pregnenolone serves as a substrate for progesterone formation. The age dependencies of 17-hydroxypregnenolone and pregnenolone in women resembled that of unconjugated dehydroepiandrosterone. These results indicate that the increased metabolic activity in gonads in adolescence concerns not only dehydroepiandrosterone as the product of the 5-ene metabolic pathway but also its precursors.


Assuntos
17-alfa-Hidroxipregnenolona/sangue , Fatores Etários , Pregnenolona/sangue , Fatores Sexuais , 17-alfa-Hidroxipregnenolona/imunologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pregnenolona/imunologia , Fatores de Tempo
18.
J Endocrinol ; 154(1): 57-62, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9246938

RESUMO

Dehydroepiandrosterone sulphate (DHEAS) and unconjugated dehydroepiandrosterone (DHEA) have been determined in the blood serum of normal subjects of both sexes from 1 month to 100 years of age. In total, 92 girls, 49 boys, 211 women and 110 men were investigated. The effects of age and sex on the levels of the hormones were measured. DHEAS levels declined rapidly during the first year of life and were maintained at a minimum level for 5 years. They increased significantly from 6 to 7 years of age and reached maximum levels in women at about 24 years and in men at about 30 years of age. They then declined rapidly in both sexes but the fall which occurred after 50 and 60 years of age respectively was only moderate. Age-related unconjugated DHEA levels were different. After the first month of life DHEA levels were relatively high and declined more slowly. The minimum level was observed in girls between 5 and 7 years and in boys between 5 and 9 years of age. A significant rise then began and levels reached a maximum in women as well as in men at about 20 years of age. In men levels then declined up to the age of 80. In women the DHEA levels declined during the next 15 years and from approximately 36 years of age they again rose significantly up to a second peak. A mild but significant decline then resumed. There was a difference in the levels of DHEA and DHEAS depending on sex. Unlike DHEAS, unconjugated DHEA was higher in women than in men. However, this difference was significant only in some age groups: during puberty (between 11 and 15 years of age), in the premenopausal period (between 36 and 45 years of age) and in the older group (after 60 years of age). Age- and sex-related dependencies were different between DHEAS and DHEA. They indicate the possible variable secretion and dynamics of their (inter)conversion. We have concluded that DHEA measurements cannot be a substitute for DHEAS and vice versa.


Assuntos
Envelhecimento/sangue , Desidroepiandrosterona/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais
19.
J Steroid Biochem Mol Biol ; 51(5-6): 315-8, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7826894

RESUMO

The results of measurement of 17-hydroxyprogesterone (17-OH-P) in 125 samples of amniotic fluid (AF) from early amniocenteses are presented. The fetuses from all pregnancies studied were unaffected by congenital adrenal hyperphasia caused by 21-hydroxylase deficiency. The AF 17-OH-P level increases slightly but significantly between the 11th and 15th week of gestation, with a maximum in the 14th week. There is no difference between the values measured in male and female fetuses. The AF 17-OH-P levels from the early gestation were compared with those from the 16th-22nd week of pregnancy (published previously). The overall differences of AF 17-OH-P concentrations when considered in all gestational age groups in the whole period 12-22 weeks were statistically insignificant. Thus, the biochemical prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency and control of its early fetal treatment could be carried out starting from the end of the first trimester in the same way as at the later period of gestation.


Assuntos
Líquido Amniótico/metabolismo , Hidroxiprogesteronas/metabolismo , Primeiro Trimestre da Gravidez/metabolismo , 17-alfa-Hidroxiprogesterona , Hiperplasia Suprarrenal Congênita/diagnóstico , Intervalos de Confiança , Feminino , Idade Gestacional , Humanos , Gravidez , Segundo Trimestre da Gravidez/metabolismo , Diagnóstico Pré-Natal , Valores de Referência , Fatores Sexuais
20.
J Steroid Biochem Mol Biol ; 48(1): 81-7, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8136309

RESUMO

The effect of long-term glucocorticoid therapy for systemic diseases on glucocorticoid receptor (GR) content and on basal and ACTH-stimulated levels of plasma and salivary cortisol 17 alpha-hydroxy-progesterone, androstenedione, 11 beta-hydroxyandrostenedione, DHEA, its sulfate and sex hormone-binding globulin (SHBG), as well as on basal levels of aldosterone, was investigated in a group of 24 children treated with prednisone for at least 8 months. The therapy was interrupted 24 h before the ACTH test and before plasma and saliva sampling. The control group consisted of 21 healthy children of corresponding age and sex. The patients were divided into two subgroups with normal and subnormal basal cortisolemia, they also differed in their response to ACTH. The GR levels in patient groups were indistinguishable from those found in controls. No correlation was found between GR content and basal levels of the above steroids or their response to ACTH. The best markers, apart from basal cortisolemia, for evaluation of the degree of suppression of adrenal function appeared to be the response of salivary (but not of plasma) cortisol and 17 alpha-hydroxy-progesterone to ACTH. Surprisingly, significantly lower levels of SHBG levels, which rose markedly after ACTH, were found in all the patients.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Hormônios Esteroides Gonadais/sangue , Prednisona/uso terapêutico , Receptores de Glucocorticoides/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Hidrocortisona/sangue , Masculino , Globulina de Ligação a Hormônio Sexual/metabolismo , Fatores de Tempo
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