Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Clin Endocrinol Metab ; 105(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32865200

RESUMO

CONTEXT: Girls with premature adrenarche (PA) may have a higher risk of developing polycystic ovary syndrome (PCOS) and metabolic syndrome. The biological purpose of adrenarche is unknown and the role of novel biosynthetic pathways remains unclear. OBJECTIVE: To compare the urinary steroid metabolome and enzyme activities of girls with PA to age-matched control girls and to published steroid values of girls with normal adrenarche and of women with PCOS and their newborn daughters. DESIGN: Prospective observational study from 2009 to 2014. SETTING: Academic pediatric endocrinology referral center. PARTICIPANTS: Twenty-three girls with PA and 22 healthy, age-matched girls. MAIN OUTCOME MEASURES: Steroid metabolites in 24-hour urine samples, including 4 progesterones, 5 corticosterones, aldosterone, 13 androgens, 2 estrogens, 14 glucocorticoids, and enzyme activities represented by metabolite ratios. RESULTS: Girls with PA had a higher body mass index (mean standard deviation scores 0.9 vs -0.3, P = 0.013). Androgen excretion was higher in PA girls than in control girls (median 3257 nmol/24 hours vs 1627 nmol/24 hours, P < 0.001), in particular metabolites from alternate androgen pathways. The amount of progesterone, corticosterone, aldosterone, estrogen, and cortisol metabolites were similar between groups. Activities of 17ß-hydroxysteroid-dehydrogenase and of 17,20-lyase were higher in girls with PA. Activities of 3ß-hydroxysteroid-dehydrogenase, 21-hydroxylase, and 5α-reductase activity were not different between groups, in contrast to published results on girls with normal adrenarche or PCOS females. CONCLUSIONS: Metabolites and enzymes involved in alternate androgen pathways appear to be markers of PA. Prospective studies should assess whether steroid production in PA also differs from adrenarche at normal timing and persists into adulthood.


Assuntos
17-Hidroxiesteroide Desidrogenases/sangue , Adrenarca/sangue , Puberdade Precoce/sangue , Esteroide 17-alfa-Hidroxilase/sangue , 17-Hidroxiesteroide Desidrogenases/metabolismo , Adrenarca/metabolismo , Adrenarca/fisiologia , Androgênios/sangue , Androgênios/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Corticosterona/sangue , Corticosterona/metabolismo , Estrogênios/sangue , Estrogênios/metabolismo , Feminino , Humanos , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Metaboloma , Puberdade Precoce/metabolismo , Esteroide 17-alfa-Hidroxilase/metabolismo , Suíça , Regulação para Cima
2.
J Clin Endocrinol Metab ; 105(10)2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750115

RESUMO

CONTEXT: The levels of adrenal androgens are increased through the action of steroidogenic enzymes with morphological changes in the adrenal zona reticularis. OBJECTIVE: We investigated longitudinal changes in androgen levels and steroidogenic enzyme activities during early childhood. DESIGN AND PARTICIPANTS: From a prospective children's cohort, the Environment and Development of Children cohort, 114 boys and 86 girls with available blood samples from ages 2, 4, and 6 years were included. OUTCOME MEASUREMENTS: Serum concentrations of adrenal androgens using liquid chromatography-tandem mass spectrometry and steroidogenic enzyme activity calculated by the precursor/product ratio. RESULTS: During ages 2 to 4 years, 17,20-lyase and dehydroepiandrosterone (DHEA) sulfotransferase activities increased (P < 0.01 for both in boys). During ages 4 to 6 years, 17,20-lyase activity persistently increased, but 3ß-hydroxysteroid dehydrogenase (HSD) and 17ß-HSD activities decreased (P < 0.01 for all). Serum DHEA sulfate (DHEA-S) levels persistently increased from 2, 4, to 6 years, and DHEA, 17-hydroxyprogesterone, and androstenedione levels increased during ages 4 to 6 years (P < 0.01 for all). Serum DHEA-S levels during early childhood were associated with body mass index z-scores (P = 0.001 in only boys). CONCLUSION: This study supports in vivo human evidence of increased 17,20-lyase and DHEA sulfotransferase activities and decreased 3ß-HSD activity during early childhood.


Assuntos
3-Hidroxiesteroide Desidrogenases/sangue , Adrenarca/sangue , Androgênios/sangue , Esteroide 17-alfa-Hidroxilase/sangue , Sulfotransferases/sangue , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/metabolismo , 17-alfa-Hidroxiprogesterona/sangue , 17-alfa-Hidroxiprogesterona/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , Adrenarca/metabolismo , Androgênios/metabolismo , Androstenodiona/sangue , Androstenodiona/metabolismo , Criança , Pré-Escolar , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/metabolismo , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Esteroide 17-alfa-Hidroxilase/metabolismo , Sulfotransferases/metabolismo , Zona Reticular/metabolismo
3.
Biomed Res Int ; 2017: 3756089, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28357399

RESUMO

Deletion of PI3K catalytic subunit p110α in adipose tissue (aP2-Cre/p110αflx/flx, α-/- hereafter) results in increased adiposity, glucose intolerance, and liver steatosis. Because this endocrine organ releases hormones like leptin, which are important in reproductive physiology, we investigated the reproductive phenotype of α-/- males. Compared to controls, α-/- males displayed delayed onset of puberty accompanied by a reduction in plasma LH levels and testicular weight. At postnatal day 30, α-/- mice exhibited normal body weight but elevated fasted plasma leptin levels. Testicular leptin gene expression was increased, whereas expression of the cholesterol transporter StAR and of P450 cholesterol side chain cleavage enzyme was decreased. Adult α-/- males were infertile and exhibited hyperandrogenemia with normal basal LH, FSH, and estradiol levels. However, neither sperm counts nor sperm motility was different between genotypes. The mRNA levels of leptin and of 17-beta-dehydrogenase 3, and enzyme important for testosterone production, were significantly higher in the testis of adult α-/- males. The mRNA levels of ERα, an important regulator of intratesticular steroidogenesis, were lower in the testis of adult and peripubertal α-/- males. We propose that chronic hyperleptinemia contributes to the negative impact that disrupting PI3K signaling in adipocytes has on puberty onset, steroidogenesis, and fertility in males.


Assuntos
Tecido Adiposo/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/genética , Infertilidade Masculina/genética , Puberdade Tardia/genética , 17-Hidroxiesteroide Desidrogenases/biossíntese , 17-Hidroxiesteroide Desidrogenases/sangue , Tecido Adiposo/patologia , Animais , Classe I de Fosfatidilinositol 3-Quinases/biossíntese , Hormônio Foliculoestimulante/sangue , Regulação da Expressão Gênica , Genótipo , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/patologia , Leptina/sangue , Leptina/genética , Hormônio Luteinizante/sangue , Masculino , Camundongos , Camundongos Transgênicos , Puberdade Tardia/sangue , Puberdade Tardia/patologia , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Testosterona/biossíntese
4.
Eur J Endocrinol ; 174(6): 801-11, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27188454

RESUMO

BACKGROUND: Men with Klinefelter syndrome (KS) show hypergonadotropic hypogonadism, but the pathogenesis of hypotestosteronemia remains unclear. Testicular steroidogenesis in KS men was evaluated over three decades ago after human chorionic gonadotropin (hCG) stimulation, but inconclusive results were obtained. Intriguingly, some recent studies show increased intratesticular testosterone concentrations in men with KS. OBJECTIVE: To analyze serum steroid profile, as a proxy of testicular steroidogenesis, after hCG stimulation in KS compared with control men. DESIGN: A prospective, longitudinal, case-control, clinical trial. METHODS: Thirteen KS patients (36±9 years) not receiving testosterone (TS) replacement therapy and 12 eugonadic controls (32±8 years) were enrolled. Serum steroids were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) at baseline and for five consecutive days after intramuscular injection of 5000IU hCG. RESULTS: Progesterone (P), 17-hydroxyprogesterone (17OHP), TS, and estradiol (E2) showed a significant increase (P<0.001) after hCG stimulation in both groups. On the contrary, androstenedione (AS) and dehydroepiandrosterone did not increase after hCG stimulation. The 17OHP/P ratio increased in both groups (P<0.001), the TS/AS ratio (17ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3) activity) did not increase after hCG in any group, and the E2/TS ratio (aromatase activity) increased significantly in both groups (P=0.009 in KS and P<0.001 in controls). Luteinizing hormone decreased after hCG in both groups (P=0.014 in KS and P<0.001 in controls), whereas follicle-stimulating hormone decreased only in control men (P<0.001). CONCLUSION: This study demonstrates for the first time using LC-MS/MS that Leydig cells of KS men are able to respond to hCG stimulation and that the first steps of steroidogenesis are fully functional. However, the TS production in KS men is impaired, possibly related to reduced hydroxysteroid deydrogenase activity due to an unfavorable intratesticular metabolic state.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Síndrome de Klinefelter/tratamento farmacológico , Testículo/efeitos dos fármacos , Testosterona/sangue , 17-Hidroxiesteroide Desidrogenases/sangue , Adulto , Gonadotropina Coriônica/farmacologia , Cromatografia Líquida , Estradiol/sangue , Humanos , Síndrome de Klinefelter/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Progesterona/sangue , Estudos Prospectivos , Espectrometria de Massas em Tandem , Resultado do Tratamento
5.
Toxicol Ind Health ; 32(7): 1266-77, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25425536

RESUMO

This study is aimed at elucidating the possible protective effects of Nigella sativa oil (NSO) in alleviating the toxicity of chlorpyrifos (CPF) on reproductive performance in male rats. Animals were orally administered with NSO (1 ml/kg/day), CPF (20 mg/kg/day), and NSO + CPF every day for 4 weeks. Results showed that CPF decreased spermatid number, sperm count, daily sperm production, and sperm motility while increased dead sperm and abnormal sperm compared with the control. Also the levels of testosterone, thyroxine levels, steroidogenic enzyme 17-ketosteroid reductase, body weight, food intake, and relative weight of reproductive organs were decreased. Thiobarbituric acid reactive substances were increased, while glutathione (GSH) and antioxidant enzymes were decreased in plasma and testes of rats treated with CPF. Histopathological examination of testes showed a decrease in the number of seminiferous tubules, form shrinkage, enlargement of the connective tissue and gametogenic changes in germ cells of rats treated with CPF. NSO alone increased testosterone, semen characteristics, GSH, and antioxidant enzymes and decreased the levels of free radicals. Furthermore, the presence of NSO with CPF alleviates its toxic effects. Our results indicated that NSO can improve semen picture and moderate CPF-induced reproductive toxicity.


Assuntos
Clorpirifos/toxicidade , Óleos de Plantas/farmacologia , Substâncias Protetoras/farmacologia , Reprodução/efeitos dos fármacos , 17-Hidroxiesteroide Desidrogenases/sangue , Animais , Antioxidantes/metabolismo , Peso Corporal , Glutationa/sangue , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/química , Substâncias Protetoras/química , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tiroxina/sangue
6.
Andrologia ; 48(4): 363-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26190442

RESUMO

This study investigated the effect of resistant maltodextrin (RMD) on reproduction in streptozotocin (STZ)-nicotinamide-induced type 2 diabetic male rats. Forty male rats were induced with diabetes by a single intraperitoneal injection of STZ (50 mg kg(-1)) and nicotinamide (100 mg kg(-1)). Five groups were analysed in total: normal, diabetic rats without RMD, diabetic rats with RMD 1.2 g per 100 g diet (1×), with RMD 2.4 g per 100 g (2×), and with RMD 6.0 g per 100 g (5×). The groups of diabetic rats with the RMD supplement, compared to those without supplement, showed improved plasma glucose control, attenuated insulin resistance and recovery of testosterone level and spermatogenesis stage. The STZ-nicotinamide-induced diabetes mellitus (DM) caused a significant reduction in serum testosterone, testis androgen receptor (AR), steroidogenic acute regulatory protein (StAR) and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) protein, but a statistical recovery in each of these was observed in the 5× group. TUNEL-positive cells were observed in the diabetic without RMD group, and RMD treatment reduced apoptotic germ cells. The expression of Bax/Bcl2 was induced in the diabetic group and also significantly reduced in the 5× group. Dietary RMD may improve metabolic control in STZ-nicotinamide-induced diabetic rats and attenuate hyperglycaemia-related impaired male reproduction and testicular function.


Assuntos
Diabetes Mellitus Experimental/complicações , Hiperglicemia/complicações , Polissacarídeos/farmacologia , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , 17-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Células Germinativas/efeitos dos fármacos , Hiperglicemia/sangue , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Masculino , Niacinamida/administração & dosagem , Niacinamida/toxicidade , Fosfoproteínas/sangue , Polissacarídeos/administração & dosagem , Ratos , Ratos Wistar , Receptores Androgênicos/análise , Estreptozocina/administração & dosagem , Estreptozocina/toxicidade , Testículo/metabolismo , Testosterona/sangue
7.
Reprod Toxicol ; 51: 57-63, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25541261

RESUMO

The aim of this study was to test whether diabetic rats exposed to alcohol demonstrate a higher degree of reproductive toxicity and suffer with elevated oxidative toxicity when compared with alcohol exposed control rats. Diabetes was induced by injecting single dose of streptozotocin and alcohol was administered through orogastric tube once daily for a period of 55 days. Daily sperm production, epididymal sperm count, motile, viable and HOS-tail coiled sperms, serum testosterone levels and testicular 3ß- and 17ß-hydroxysteroid dehydrogenase activity levels were significantly decreased in diabetic rats. Significant reduction in testicular and epididymal superoxide dismutase and catalase activity levels, and elevation in lipid peroxidation products were observed in diabetic rats. Similar reproductive and oxidative toxicity was observed in alcohol treated control rats. Further, alcohol exposed diabetic rats showed additional deterioration in reproductive endpoints and noteworthy elevation in oxidative toxicity suggesting that treatment with alcohol further deteriorates sexual dysfunction in STZ-induced diabetic rats.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Etanol/toxicidade , Estresse Oxidativo/efeitos dos fármacos , 17-Hidroxiesteroide Desidrogenases/sangue , Animais , Catalase/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Epididimo/efeitos dos fármacos , Epididimo/metabolismo , Epididimo/patologia , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Malondialdeído/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Ratos Wistar , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testosterona/sangue
8.
Toxicol Ind Health ; 31(5): 467-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-23406956

RESUMO

Atherosclerosis is a condition caused by lipid build-up and inflammation in the arteries, so hyperlipidemia is the major reason for atherosclerosis. Testis was found to be negatively affected by hyperlipidemia which leads to its impaired functions. Vitamin E and l-carnitine have well-known lipid-lowering and antioxidative activities. Triton WR 1339 is a non-ionic detergent, which induces severe hyperlipidemia by inhibition of lipoprotein lipase. The present study evaluates the protective role of vitamin E and l-carnitine on the testis in atherosclerosis and detects the most effective choice for protection against atherosclerosis; vitamin E, l-carnitine or a combination of both. A total of 80 albino male rats were divided into eight groups (10 rats for each group): control (G1), triton (G2), l-carnitine (G3), triton + l-carnitine (G4), vitamin E (G5), triton + vitamin E (G6), l-carnitine + vitamin E (G7) and triton + l-carnitine + vitamin E (G8). Data showed a significant increase in the levels of total cholesterol (TC), triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), 17 beta hydroxysteroid dehydrogenase (17 ß HSD), testicular catalase and malondialdehyde (MDA) in G2 when compared with G1, whereas high-density lipoprotein cholesterol (HDL-C), serum testosterone, testicular 17 ketosteroid reductase (17 KSR), total thiol and glutathione-S-transferase (GST) data showed a significant decrease in G2 when compared with G1. Treatment with l-carnitine or/and vitamin E helps in improving the adverse effect of triton; also the histological changes confirm this finding. So the present study recommends all people to include l-carnitine and vitamin E in their diet to be protected against atherosclerosis.


Assuntos
Carnitina/farmacologia , Doenças das Artérias Carótidas/prevenção & controle , Testículo/efeitos dos fármacos , Vitamina E/farmacologia , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Doenças das Artérias Carótidas/tratamento farmacológico , Catalase/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Glutationa Transferase/sangue , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Testosterona/sangue , Triglicerídeos/sangue
9.
Asian J Androl ; 15(3): 368-74, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23524530

RESUMO

Populations living at high altitudes (HAs), particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis (16 g dl(-1)21 g dl(-1)). Elevated haemoglobin values (EE) are associated with chronic mountain sickness, a condition reflecting the lack of adaptation to HA. According to current data, native men from regions of HA are not adequately adapted to live at such altitudes if they have elevated serum testosterone levels. This seems to be due to an increased conversion of dehydroepiandrosterone sulphate (DHEAS) to testosterone. Men with erythrocytosis at HAs show higher serum androstenedione levels and a lower testosterone/androstenedione ratio than men with EE, suggesting reduced 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activity. Lower 17beta-HSD activity via Δ4-steroid production in men with erythrocytosis at HA may protect against elevated serum testosterone levels, thus preventing EE. The higher conversion of DHEAS to testosterone in subjects with EE indicates increased 17beta-HSD activity via the Δ5-pathway. Currently, there are various situations in which people live (human biodiversity) with low or high haemoglobin levels at HA. Antiquity could be an important adaptation component for life at HA, and testosterone seems to participate in this process.


Assuntos
Adaptação Fisiológica/fisiologia , Altitude , Policitemia/etiologia , Testosterona/sangue , 17-Hidroxiesteroide Desidrogenases/sangue , Androstenodiona/sangue , Animais , Sulfato de Desidroepiandrosterona/sangue , Eritropoese , Hemoglobinas/metabolismo , Humanos , Hipóxia/sangue , Hipóxia/fisiopatologia , Policitemia/sangue , Policitemia/fisiopatologia
10.
J Sex Med ; 10(10): 2586-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22594312

RESUMO

INTRODUCTION: 17ß-hydroxysteroid dehydrogenase type 3 (HSD17B3) isoenzyme is present almost exclusively in the testes and converts delta 4 androstenedione to testosterone. Mutations in the HSD17B3 gene cause HSD17B3 deficiency and result in 46,XY Disorders of Sex Development (46,XY DSD). AIM: This study aimed to present the clinical and biochemical features of a Tunisian patient who presented a sexual ambiguity orienting to HSD17B3 deficiency and to search for a mutation in the HSD17B3 gene by DNA sequencing. METHODS: Polymerase chain reaction (PCR) amplification and subsequent sequencing of all the coding exons of HSD17B3 gene were performed on genomic DNA from the patient, her family, and 50 controls. RESULTS: Genetic mutation analysis of the HSD17B3 gene revealed the presence of a novel homozygous nonsense mutation in the exon 9 (c.618 C>A) leading to the substitution p.C206X. The mutation p.C206X in the coding exons supports the hypothesis of HSD17B3 deficiency in our patient. CONCLUSION: The patient described in this study represented a new case of a rare form of 46,XY DSD, associated to a novel gene mutation of HSD17B3 gene. The screening of this mutation is useful for confirming the diagnosis of HSD17B3 deficiency and for prenatal diagnosis.


Assuntos
17-Hidroxiesteroide Desidrogenases/deficiência , Códon sem Sentido , Transtorno 46,XY do Desenvolvimento Sexual/genética , Ginecomastia/genética , Erros Inatos do Metabolismo de Esteroides/genética , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/genética , Androstenodiona/sangue , Biomarcadores/sangue , Pré-Escolar , Análise Mutacional de DNA/métodos , Transtorno 46,XY do Desenvolvimento Sexual/sangue , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Transtorno 46,XY do Desenvolvimento Sexual/enzimologia , Éxons , Feminino , Predisposição Genética para Doença , Ginecomastia/sangue , Ginecomastia/diagnóstico , Ginecomastia/enzimologia , Homozigoto , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Erros Inatos do Metabolismo de Esteroides/sangue , Erros Inatos do Metabolismo de Esteroides/diagnóstico , Erros Inatos do Metabolismo de Esteroides/enzimologia , Testosterona/sangue , Tunísia
11.
Nepal Med Coll J ; 15(1): 62-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24592797

RESUMO

Male rats exposed to continous light for 70 days showed an increased weights of testis, accessory sex organs, serum levels of FSH, LH, testosterone, testicular 17beta-hydroxysteroid dehydrogenase (1beta-HSD) activity and alpha 2u-globulin, while 3beta-hydroxysteroid dehydrogenase activity showed no significant changes. Prolonged light exposure also stimulated sepermatogenesis in rats. These results suggest that alpha 2u-globulin possibly stimutates the male gonad by inducing pituitary gonadotropins in continuous light-exposed rats.


Assuntos
alfa-Globulinas/metabolismo , Luz , Espermatogênese/efeitos da radiação , Testículo/efeitos da radiação , 17-Hidroxiesteroide Desidrogenases/sangue , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão/efeitos da radiação , Radioimunoensaio , Ratos , Testosterona/sangue
12.
Mol Vis ; 17: 2297-310, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21921981

RESUMO

PURPOSE: To evaluate the relationship among single nucleotide polymorphisms (SNPs) in steroidogenesis enzyme genes, serum levels of sex steroids, and high myopia in Taiwanese male and female populations. METHODS: A campus-based sample of 283 cases (145 males and 138 females) with high myopia and 280 controls (144 males and 136 females) with low myopia or emmetropia was studied. Estradiol, progesterone, and testosterone levels were determined using enzyme-linked immunosorbent assay kits. We genotyped six SNPs within five steroidogenesis enzyme genes (17 alpha-hydroxylase/17,20 lyase [CYP17A1], 3 beta-hydroxysteroid dehydrogenase [HSD3B1], 17 beta-hydroxysteroid dehydrogenase 1 [HSD17B1], steroid-5-alpha-reductase, alpha polypeptide 2 [SRD5A2], and aromatase [CYP19A1]) using polymerase chain reaction-restriction fragment length polymorphism methods. Student's t-tests, χ(2) tests, logistic regression, multifactor dimensionality reduction (MDR) methods, and ANOVA were used to determine significance. RESULTS: An MDR analysis corroborated the synergistic genotype association and demonstrated that synergistic interaction between rs6203 (HSD3B1), rs10046 (CYP19A1), and sex might confer susceptibility to high myopia (p=0.019). In both male and female subjects, levels of testosterone were significantly higher in cases than in controls; in male subjects, the levels of estradiol were significantly higher and those of progesterone were significantly lower in cases (all p-values <0.001). The rs605059 (HSD17B1), with sex-gene interaction, showed association with estradiol levels in males (p=0.035) and testosterone levels in females (p=0.027). CONCLUSIONS: Testosterone levels correlate with high myopia, and interaction of steroidogenesis enzyme genes and sex may be a modulating factor in sex hormone metabolism and high-myopia risk.


Assuntos
Povo Asiático , Estradiol/genética , Miopia/genética , Esteroides/sangue , Testosterona/genética , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/genética , Adulto , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Estradiol/sangue , Estradiol Desidrogenases/sangue , Estradiol Desidrogenases/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Miopia/sangue , Miopia/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores Sexuais , Esteroide 17-alfa-Hidroxilase/sangue , Esteroide 17-alfa-Hidroxilase/genética , Taiwan/epidemiologia , Testosterona/sangue
13.
Contraception ; 75(5): 390-400, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17434022

RESUMO

OBJECTIVE: To study a method of chemical sterilization and its efficacy in adult male stray dogs. METHODS: Sterilization was performed 45 days after a single bilateral intratesticular injection of calcium chloride (CaCl(2)) at the doses of 5, 10, 15 or 20 mg per testis per kg body weight. RESULTS: Histomorphological measures of testes showed total necrosis of testicular tissue at 45 days after an injection of either 10 or 15 or 20 mg CaCl(2) along with fibrosis and hyalinization in seminiferous tubules and interstitial spaces. Infiltration of leucocytes was also observed with the 10- or 15-mg dose. Disintegration of germ cell arrangement in seminiferous tubules and washing out of germ cells from the tubules were noted with the 5-mg dose. Relative organ weight, epididymal sperm count, plasma and intratesticular concentrations of testosterone, testicular activities of Delta(5),3beta-hydroxysteroid dehydrogenase (Delta(5),3beta-HSD), 17beta-hydroxysteroid dehydrogenase (17beta-HSD), glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) and testicular contents of glutathione (GSH) and glutathione disulphide (GSSG) and the ratio of GSH/GSSG, all were declined in each of the calcium chloride treated groups in comparison to the control group. Increases occurred in testicular malondialdehyde (MDA) and plasma concentrations of LH and FSH with each of the treatments by comparison with the control group. Plasma concentrations of cortisol, fasting blood sugar level, blood urea nitrogen as well as packed cell volume (PCV) and total plasma protein were recorded to monitor the changes in chronic stress in the experimental animals. Changes in these parameters were not significant. CONCLUSION: An intratesticular injection of CaCl(2) at specified doses could be a suitable method of sterilization in preference to surgical castration of dogs.


Assuntos
Cloreto de Cálcio/administração & dosagem , Hidrocortisona/sangue , Esterilização Reprodutiva/métodos , Testículo/efeitos dos fármacos , Testosterona/sangue , 17-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/sangue , Animais , Glicemia/efeitos dos fármacos , Proteínas Sanguíneas/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Cães , Relação Dose-Resposta a Droga , Hormônio Foliculoestimulante/sangue , Glutationa/metabolismo , Hematócrito , Hormônio Luteinizante/sangue , Masculino , Malondialdeído/metabolismo , Contagem de Espermatozoides , Superóxido Dismutase/metabolismo , Testículo/metabolismo
14.
J Mol Med (Berl) ; 84(8): 651-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16572348

RESUMO

17beta-hydroxysteroid dehydrogenase (17beta-HSD) and 5alpha-reductase isoenzymes play a crucial role in the formation and metabolism of sex steroids. Not only the key androgens testosterone and dihydrotestosterone but also their precursors are potent activators of the androgen receptor and are, therefore, likely to act as determinants of male sexual differentiation and maturation in a differentially regulated way. The aim of the present study was to relatively quantify the expression of the mRNA of 17beta-HSD isoenzymes, namely, type 1, 2, 3, 4, 5, 7, and 10, together with the 5alpha-reductase type 1 and 2, and the androgen receptor in normal human males and females. RNA was isolated from peripheral blood cells of both sexes and from genital skin fibroblasts (GSFs) of two different localizations (foreskin and scrotal skin) obtained from phenotypically normal males. mRNA expression was semi-quantified by quantitative reverse-transcriptase polymerase chain reaction with the LightCycler Instrument (Roche). The examined enzymes show statistically significant differences in their transcription pattern between the blood and the GSF RNA samples. Within the GSF samples, there are also significant variations between the two examined localizations in the transcription of 17beta-HSD type 1, 2, 4, and 5 as well as for the androgen receptor. We found large interindividual variation of enzyme transcription patterns in all investigated tissues. In peripheral blood cells, no sex-specific differences were seen. We conclude that sex steroid enzymes are expressed not only in genital primary target tissues but also in peripheral blood. The expression in different target tissues may contribute to both the individual sexual and tissue-specific phenotype in humans.


Assuntos
17-Hidroxiesteroide Desidrogenases/biossíntese , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/biossíntese , Hormônios Esteroides Gonadais/biossíntese , Receptores Androgênicos/biossíntese , 17-Hidroxiesteroide Desidrogenases/sangue , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular , Células Cultivadas , Criança , Pré-Escolar , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Prepúcio do Pênis/citologia , Prepúcio do Pênis/metabolismo , Humanos , Lactente , Isoenzimas/biossíntese , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , RNA Mensageiro/biossíntese , Receptores Androgênicos/sangue , Fatores Sexuais
15.
Gynecol Obstet Invest ; 61(4): 208-15, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16479139

RESUMO

BACKGROUND: Insulin-lowering agents are reported to be useful in treating polycystic ovary syndrome (PCOS) anovulation. It has been suggested that lower insulin levels secondarily affect ovarian tissue, although the direct mechanism of action has not yet been verified. Here we investigated if these agents directly affect the ovary. METHODS: Thirty female Wister rats were studied. Six control rats were injected subcutaneously with 0.2 ml sesame oil, while 24 rats used as PCOS models were injected subcutaneously with dehydroepiandrosterone (DHEA) and divided into four groups. Six rats were injected with only DHEA, while the remaining 18 rats received metformin, pioglitazone or troglitazone. The ovaries were immunohistochemically stained with anti- testosterone and anti-17beta-HSD antibodies, and then evaluated for morphological changes. RESULTS: In the DHEA administration group, the number of atretic follicles significantly increased compared to that of control rats. The insulin-lowering agents did not improve the multicystic appearance. Serum testosterone concentrations significantly increased with DHEA administration, but the increase was inhibited by oral administration of insulin-lowering agents. Testosterone deposits in ovarian tissue were also reduced by feeding rats insulin-lowering agents. CONCLUSION: Insulin-lowering agents affected ovarian tissue by inhibiting testosterone biosynthesis in vivo.


Assuntos
Hipoglicemiantes/uso terapêutico , Ovário/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Testosterona/biossíntese , 17-Hidroxiesteroide Desidrogenases/sangue , 17-Hidroxiesteroide Desidrogenases/efeitos dos fármacos , Adjuvantes Imunológicos/toxicidade , Animais , Cromanos/uso terapêutico , Desidroepiandrosterona/toxicidade , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Imuno-Histoquímica , Insulina/sangue , Metformina/uso terapêutico , Pioglitazona , Síndrome do Ovário Policístico/induzido quimicamente , Ratos , Ratos Wistar , Testosterona/sangue , Tiazolidinedionas/uso terapêutico , Troglitazona
16.
Reprod Biol Endocrinol ; 2: 22, 2004 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-15140254

RESUMO

BACKGROUND: In the rat, the maintenance of gestation is dependent on progesterone production from the corpora lutea (CL), which are under the control of pituitary, decidual and placental hormones. The luteal metabolism of progesterone during gestation has been amply studied. However, the regulation of progesterone synthesis and degradation during pseudopregnancy (PSP), in which the CL are mainly under the control of pituitary prolactin (PRL), is not well known. The objectives of this investigation were: i) to study the luteal metabolism of progesterone during PSP by measuring the activities of the enzymes 3beta-hydroxysteroid dehydrogenase (3betaHSD), involved in progesterone biosynthesis, and that of 20alpha-hydroxysteroid dehydrogenase (20alphaHSD), involved in progesterone catabolism; and ii) to determine the role of decidualization on progesterone metabolism in PSP. METHODS: PSP was induced mechanically at 10:00 h on the estrus of 4-day cycling Wistar rats, and the stimulus for decidualization was provided by scratching the uterus on day 4 of PSP. 3betaHSD and 20alphaHSD activities were measured in the CL isolated from ovaries of PSP rats using a spectrophotometric method. Serum concentrations of progesterone, PRL, androstenedione, and estradiol were measured by radioimmunoassay (RIA). RESULTS: The PSP stage induced mechanically in cycling rats lasted 11.3 +/- 0.09 days (n = 14). Serum progesterone concentration was high until day 10 of PSP, and declined thereafter. Serum PRL concentration was high on the first days of PSP but decreased significantly from days 6 to 9, having minimal values on days 10 and 11. Luteal 3betaHSD activities were elevated until day 6 of PSP, after which they progressively declined, reaching minimal values at the end of PSP. Luteal 20alphaHSD activities were very low until day 9, but abruptly increased at the end of PSP. When the deciduoma was induced by scratching the uterus of pseudopregnant animals on day 4 (PSP+D), PSP was extended to 18 +/- 2.2 days (n = 8). In PSP + D rats, serum progesterone and PRL levels, and luteal 3betaHSD activities were higher than in pseudopregnant rats on day 11. Decidualization also prevented the increase in luteal 20alphaHSD activities observed on day 11 of PSP. Administration of the dopaminergic agonist CB154 in PSP + D rats on day 10 of PSP induced a decline in both serum PRL and progesterone on day 11 of PSP, values that were not different from that of pseudopregnant controls. CONCLUSIONS: We have established that during the final period of PSP a decline in progesterone biosynthesis occurs before the increase in progesterone catabolism. We have also shown that decidualization in pseudopregnant rats extends the life of the CL by prolonging the production of pituitary PRL, and by maintaining high 3betaHSD and low 20alphaHSD activities within the CL leading to sustained production of progesterone.


Assuntos
17-Hidroxiesteroide Desidrogenases/metabolismo , 20-Hidroxiesteroide Desidrogenases/metabolismo , Corpo Lúteo/enzimologia , Deciduoma/fisiologia , Pseudogravidez/enzimologia , 17-Hidroxiesteroide Desidrogenases/sangue , 20-Hidroxiesteroide Desidrogenases/sangue , Androstenodiona/sangue , Animais , Bromocriptina/farmacologia , Dopamina/metabolismo , Estradiol/sangue , Feminino , Fase Luteal/sangue , Fase Luteal/fisiologia , Progesterona/biossíntese , Progesterona/sangue , Prolactina/biossíntese , Prolactina/sangue , Pseudogravidez/sangue , Ratos , Ratos Wistar
17.
J Clin Endocrinol Metab ; 88(9): 4180-5, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12970284

RESUMO

We studied cortisol metabolism together with insulin sensitivity [homeostatic model assessment (HOMA)] and renal hemodynamics in 19 salt-resistant (sr) and nine salt-sensitive (ss) normotensive subjects after a low- and high-salt diet. Results are described as high- vs. low-salt diet. Sum of urinary cortisol metabolite excretion (sum(metabolites)) increased in sr subjects (3.8 +/- 1.6 vs. 3.1 +/- 1.1 microg/min per square meter, P < 0.05) and decreased in ss subjects (2.3 +/- 1.0 vs. 2.9 +/- 1.1 microg/min per square meter, P < 0.05). Plasma 0830 h cortisol decreased in sr subjects but did not change significantly in ss subjects. In all subjects, the absolute blood pressure change correlated negatively with the percentage change in sum(metabolites) (P < 0.05) and positively with the percentage change in renal vascular resistance (P < 0.05). Sum(metabolites) during high-salt diet correlated negatively with the percentage changes in plasma 0830 h cortisol (P < 0.05) and renal vascular resistance (P = 0.05). HOMA did not change in either group, but the percentage change in HOMA correlated positively with the percentage change in plasma cortisol (P = 0.001) and negatively with the percentage change in sum(metabolites) (P < 0.01). Parameters of 11 beta-hydroxysteroid dehydrogenase activity were not different between groups and did not change. In conclusion, these data suggest that cortisol elimination is affected differently after salt loading in sr and ss subjects. Changes in circulating cortisol might contribute to individual sodium-induced alterations in insulin sensitivity.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hidrocortisona/metabolismo , Cloreto de Sódio na Dieta/farmacologia , 17-Hidroxiesteroide Desidrogenases/sangue , Adulto , Peso Corporal/efeitos dos fármacos , Cortisona/sangue , Feminino , Taxa de Filtração Glomerular , Homeostase/efeitos dos fármacos , Humanos , Hidrocortisona/urina , Masculino , Circulação Renal/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Sódio/urina
18.
J Clin Endocrinol Metab ; 86(9): 4536-42, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11549704

RESUMO

The physical changes that herald the onset of puberty result from the combination of adrenarche and gonadarche. To examine adrenal maturation and associated changes in growth without the confounding effects of changes in the gonadal steroid milieu, we performed a longitudinal study in 14 young girls with idiopathic central precocious puberty during long-term pituitary-gonadal suppression. Beginning at the mean age of 2.9 yr, dehydroepiandrosterone sulfate levels, linear growth, skeletal maturation, body mass index, and secondary sexual development were evaluated at 3- to 6-month intervals for up to 12.3 yr. In 12 of the girls, levels of dehydroepiandrosterone, androstenedione, 17-hydroxypregnenolone, and 17alpha-hydroxyprogesterone were determined before and after acute ACTH stimulation every 6 months to investigate the maturation of adrenal steroidogenic enzyme activity. Serum dehydroepiandrosterone sulfate levels rose progressively throughout the study. An exponential model fit the longitudinal datasets well and indicated that dehydroepiandrosterone sulfate levels increased approximately 22%/yr from the youngest age onward. Increasing activity of 17-20 lyase (CYP17) and decreasing activity of 3beta-hydroxysteroid dehydrogenase were also evident in preadrenarchal subjects. When controlled for chronological age, no significant associations were noted between weight, body mass index, or body surface area and dehydroepiandrosterone sulfate levels. However, similar analyses revealed modest correlations of both height and growth velocity with dehydroepiandrosterone sulfate levels. Our results suggest that adrenarche is not the result of sudden rapid changes in adrenal enzyme activities or adrenal androgen concentrations; rather, adrenarche may be a gradual maturational process that begins in early childhood.


Assuntos
Glândulas Suprarrenais/crescimento & desenvolvimento , 17-Hidroxiesteroide Desidrogenases/sangue , 17-alfa-Hidroxipregnenolona/sangue , 17-alfa-Hidroxiprogesterona/sangue , Hormônio Adrenocorticotrópico , Androstenodiona/sangue , Estatura/fisiologia , Pré-Escolar , Sulfato de Desidroepiandrosterona/sangue , Feminino , Hormônios/sangue , Humanos , Estudos Longitudinais , Esteroide 17-alfa-Hidroxilase/sangue
19.
Endocr Res ; 26(2): 247-62, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10921451

RESUMO

The effects of single dose, 4 consecutive days, 4 and 8 weekly doses of methotrexate (MTX) treatment (3 mg/kg body weight, intramuscularly) with and without leucovorin (LCN) supplementation (0.3 mg/kg body weight, intramuscularly) on serum testosterone titres, total, free and esterified cholesterol concentrations and steroidogenic enzymes, viz. 3beta- and 17beta-hydroxy steroid dehydrogenase activities were studied in adult albino rats. MTX treatment caused a marked reduction in serum testosterone titres in all the treatment groups in a duration-dependent manner. LCN supplementation did not restore serum testosterone titres to normalcy. Total and free cholesterol concentrations remained unaltered in both MTX and MTX + LCN treated groups. On the other hand, a marked increase in esterified cholesterol concentration was evident only in weekly dose treatment groups. The specific activities of 3beta- and 17beta-hydroxy steroid dehydrogenase were markedly diminished in both MTX and MTX + LCN treated groups. The results suggest the inhibitory effect of MTX on steroidogenesis.


Assuntos
Metotrexato/farmacologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/biossíntese , 17-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , 17-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , 3-Hidroxiesteroide Desidrogenases/sangue , Animais , Colesterol/sangue , Ésteres do Colesterol/sangue , Inibidores Enzimáticos/farmacologia , Leucovorina/administração & dosagem , Leucovorina/farmacologia , Masculino , Metotrexato/administração & dosagem , Ratos , Ratos Wistar , Testosterona/sangue
20.
Life Sci ; 58(17): 1469-74, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8622573

RESUMO

The purpose of the present study was to evaluate the effects of anti-alpha-2U-globulin on pituitary-gonadal functions in male rats. Adult male rats were given injections of anti-alpha-2u-globulin (1 mg/day) for 14 days, when they were killed 7 days after the last injection, serum levels of gonadotrophins and testosterone measured by radioimmunoassays, were less, testicular delta 3 beta- and 17 beta-hydroxy-steroid dehydrogenase (3 beta- and 17 beta-HSD) activities were suppressed, spermatogenesis was inhibited and serum level of alpha-2u-globulin was decreased in anti-alpha-2u-globulin treated rats. Administration of alpha-2u-globulin (1.5 mg/day) for 7 days to anti-alpha-2u-globulin treated rats reversed the 3beta-HSD and 17beta-HSD activities and serum levels of gonadotrophins, testosterone and alpha-2u-globulin, while spermatogenesis was restored to normal. The results indicate that changes in testicular steroidogenesis and spermatogenesis in rats after passive immunization against alpha-2u-globulin may be due to decrease in availability of endogenous alpha-2u-globulin.


Assuntos
alfa-Globulinas/imunologia , Imunização Passiva , Testículo/fisiologia , 17-Hidroxiesteroide Desidrogenases/sangue , 3-Hidroxiesteroide Desidrogenases/sangue , alfa-Globulinas/fisiologia , Animais , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Testículo/enzimologia , Testosterona/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...