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1.
Probl Endokrinol (Mosk) ; 69(2): 80-91, 2023 May 11.
Artigo em Russo | MEDLINE | ID: mdl-37448275

RESUMO

AIM: To reveal the peculiarities of steroidogenesis and arterial hypertension in «physiological¼ hyperandrogenism in men. MATERIALS AND METHODS: One-stage simultaneous study. The groups of men with hyperandrogenism caused by increased total testosterone (n=34) and those with hyperandrogenism caused by increased dihydrotestosterone (DHT) (n=66) were compared. In determining the type of hyperandrogenism and allocating patients to groups, DHT and total testosterone levels were determined by enhanced chemiluminescence. Subgroups of men with and without arterial hypertension were compared in the group of patients with hyperandrogenism due to an increase in total testosterone. Body mass index, waist circumference, systolic and diastolic blood pressure, pulse, and LH, SBHG, estradiol, blood multisteroid levels by isotope dilution liquid chromatography/tandem mass spectrometry, glucose, blood lipid spectrum, uric acid, creatinine, renin, potassium, sodium, and blood chloride were assessed in all patients. Patients with arterial hypertension additionally underwent daily BP monitoring, albuminuria assessment, electrocardiography, ocular fundus examination. The baseline threshold level of significance was p<0.05. For multiple comparisons, the p significance level was calculated using the Bonferroni correction. RESULTS: Statistically significant differences were found in the levels of 17-hydroxypregnenolone, 17-hydroxyprogesterone, and androstenedione, which were higher in men with elevated levels of total testosterone. No statistically significant differences in other laboratory parameters were found. No cases of increased blood pressure were detected in the group of men with elevated DHT. In the group of men with elevated total testosterone, 23,5% of men with arterial hypertension without targetorgan lesions were identified, while hyperandrogenism was associated with 17,6% of cases. Arterial hypertension associated with hyperandrogenism was characterized by a rise in blood pressure in the early morning hours. Estradiol levels, while remaining within normal limits, were statistically significantly lower in patients with arterial hypertension compared with men with elevated testosterone but without hypertension. CONCLUSION: No cases of arterial hypertension were observed in «physiological¼ hyperandrogenism due to elevated DHT levels, whereas its incidence in «physiological¼ hyperandrogenism due to elevated total testosterone was 23,5%. The features of steroidogenesis were increased production of 17-hydroxypregnenolone, 17-hydroxyprogesterone, and androstenedione in men with testosterone hyperandrogenism and decreased estradiol production in patients with arterial hypertension compared with patients without testosterone hyperandrogenism.


Assuntos
Hiperandrogenismo , Hipertensão , Doenças Ovarianas , Feminino , Humanos , Masculino , Hiperandrogenismo/complicações , Androstenodiona , 17-alfa-Hidroxipregnenolona , Testosterona , Di-Hidrotestosterona , Estradiol , 17-alfa-Hidroxiprogesterona , Hipertensão/complicações
2.
J Steroid Biochem Mol Biol ; 231: 106311, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37060931

RESUMO

Steroid hormone level is a crucial factor affecting the outcomes of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). The purpose of this study was to evaluate serum steroid metabolome on the day of oocyte retrieval in women with polycystic ovarian syndrome (PCOS) and explore whether specific steroids can be potential indicators to improve the prediction of pregnancy outcomes in PCOS patients undergoing IVF/ICSI. In this study, the serum levels of 21 steroids in 89 women with PCOS and 73 control women without PCOS on the day of oocyte retrieval of the first IVF/ICSI treatment cycle were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). All patients subsequently received good-quality embryo transfer, and the correlation between their steroid profiles and pregnancy outcomes of the first embryo transfer (ET) was retrospectively analyzed. We found PCOS patients had aberrant levels of 11 out of 21 steroid hormones compared to control individuals, with androgen steroid hormones being considerably enhanced. Enzyme activity evaluation indicated that PCOS women might have abnormal activity of CYP17A1, CYP21A2, CYP11B2, CYP19A1, HSD3B, HSD11B, and HSD17B. Additionally, the level of 18-hydroxycorticosterone (p = 0.014), corticosterone (p = 0.035), and 17-hydroxypregnenolone (p = 0.005) were markedly higher in live birth group than in non- live birth group for PCOS women following frozen embryo transfer (FET). Multiple logistic regressions indicated that 18-hydrocorticosterone and 17-hydroxypregnenolone were independently associated with live birth outcomes of PCOS women following FET. Receiver operating characteristic (ROC) curve analysis revealed that 0.595 ng/mL for 18-hydrocorticosterone level (AUC: 0.6936, p = 0.014).and 2.829 ng/mL for 17-hydroxypregnenolone level (AUC: 0.7215, p = 0.005) were the best cutoff values to predict live birth outcomes of PCOS. In conclusion, the blood steroid metabolome was closely related to the IVF/ICSI outcomes of PCOS patients. 18-hydroxycorticosterone and 17-hydroxypregnenolone might be potential indicators to predict pregnancy outcomes of PCOS undergoing IVF/ICSI treatment.


Assuntos
Síndrome do Ovário Policístico , Resultado da Gravidez , Masculino , Humanos , Gravidez , Feminino , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/complicações , 18-Hidroxicorticosterona , Recuperação de Oócitos/métodos , Estudos Retrospectivos , 17-alfa-Hidroxipregnenolona , Cromatografia Líquida , Taxa de Gravidez , Sêmen , Espectrometria de Massas em Tandem , Fertilização in vitro/métodos , Esteroide 21-Hidroxilase
3.
Mol Hum Reprod ; 28(10)2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36069625

RESUMO

Follicles are the functional unit of the ovary and several methods have been developed to grow follicles ex vivo, which recapitulate key events of oogenesis and folliculogenesis. Enzymatic digestion protocols are often used to increase the yield of follicles from the ovary. However, the impact of these protocols on the outermost theca and granulosa cells, and thereby follicle function, is not well defined. To investigate the impact of enzymatic digestion on follicle function, we collected preantral follicles from CD1 mice either by enzymatic digestion (Enzy-FL) or mechanical isolation (Mech-FL) and compared follicle growth, steroidogenesis and cell differentiation within an encapsulated in vitro follicle growth system which maintains the 3D architecture of the oocyte and its surrounding somatic cells. Follicles were encapsulated in 0.5% alginate and cultured for 8 days. Compared with Enzy-FL, Mech-FL grew more rapidly and produced significantly higher levels of androstenedione, estradiol and progesterone. The expression of theca-interstitial cell marker genes, Cyp17a1, which encodes 17-hydroxylase/17, 20-lyase and catalyzes the hydroxylation of pregnenolone and progesterone to 17-hydroxypregnenolone and 17-hydroxyprogesterone, and the conversion of these products into dehydroepiandrosterone and androstenedione, and Star, which encodes a transport protein essential for cholesterol entry into mitochondria, were also higher in Mech-FL than in Enzy-FL. Mech-FL maintained an intact theca-interstitial layer on the outer edge of the follicle that phenocopied in vivo patterns as confirmed by alkaline phosphatase staining, whereas theca-interstitial cells were absent from Enzy-FL from the onset of culture. Therefore, preservation of the theca cell layer at the onset of culture better supports follicle growth and function. Interestingly, granulosa cells in the outermost layers of Enzy-FL expressed CYP17A1 by Day 4 of culture while maintaining inhibin α-subunit expression and a cuboidal nucleus. Thus, in the absence of theca-interstitial cells, granulosa cells have the potential to differentiate into androgen-producing cells. This work may have implications for human follicle culture, where enzymatic isolation is required owing to the density of the ovarian cortex.


Assuntos
Liases , Progesterona , 17-alfa-Hidroxipregnenolona/metabolismo , 17-alfa-Hidroxiprogesterona/metabolismo , Alginatos/metabolismo , Fosfatase Alcalina/metabolismo , Androgênios/metabolismo , Androstenodiona/metabolismo , Animais , Proteínas de Transporte/metabolismo , Desidroepiandrosterona/metabolismo , Estradiol/metabolismo , Feminino , Células da Granulosa/metabolismo , Humanos , Inibinas/metabolismo , Liases/metabolismo , Camundongos , Pregnenolona/metabolismo , Progesterona/metabolismo , Células Tecais
4.
Endocrine ; 78(2): 373-379, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35907083

RESUMO

PURPOSE: This study aims to evaluate the correlations between the severity of the disease and serum steroid levels by analyzing the serum steroid levels in COVID-19 patients with different levels of disease progression and the control group. METHODS: Morning serum Aldosterone, 11-deoxycortisol, Androstenedione, 17-hydroxyprogesterone, Dihydrotestosterone (DHT), Dehydroepiandrosterone (DHEA), Corticosterone, Dehydroepiandrosterone sulfate (DHEAS), Estrone, Estradiol, Progesterone, 11-deoxycorticosterone, Cortisol, Corticosterone, Androsterone, Pregnenolone, 17-hydroxypregnenolone and 21-deoxycortisol levels were measured in 153 consecutive patients were grouped as mild, moderate, and severe based on the WHO COVID-19 disease severity classification and the control group. Steroid hormone levels were analyzed at once with a liquid chromatography-tandem mass spectrometric method (LC-MS/MS). RESULTS: In our study, nearly all steroids were statistically significantly higher in the patients' group than in the control group (p < 0.001). Also, DHEA was an independent indicator of the disease severity with COVID-19 CONCLUSIONS: Our study reveals that the alteration in steroid hormone levels was correlated with disease severity. Also, steroid hormone levels should be followed up during COVID-19 disease management.


Assuntos
COVID-19 , Cortodoxona , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Androstenodiona , 17-alfa-Hidroxipregnenolona , Sulfato de Desidroepiandrosterona , Hidrocortisona , Estrona , Progesterona , Corticosterona , Di-Hidrotestosterona , Androsterona , Aldosterona , 17-alfa-Hidroxiprogesterona , Pregnenolona , Estradiol , Índice de Gravidade de Doença , Desoxicorticosterona
5.
Front Endocrinol (Lausanne) ; 12: 633785, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149610

RESUMO

Cytochrome P450s (CYPs) are an essential family of enzymes in the human body. They play a crucial role in metabolism, especially in human steroid biosynthesis. Reactions catalyzed by these enzymes are highly stereo- and regio-specific. Lack or severe malfunctions of CYPs can cause severe diseases and even shorten life. Hence, investigations on metabolic reactions and structural requirements of substrates are crucial to gain further knowledge on the relevance of different enzymes in the human body functions and the origin of diseases. One key enzyme in the biosynthesis of gluco- and mineralocorticoids is CYP21A2, also known as steroid 21-hydroxylase. To investigate the steric and regional requirements of substrates for this enzyme, we performed whole-cell biotransformation assays using a strain of fission yeast Schizosaccharomyces pombe recombinantly expressing CYP21A2. The progestogens progesterone, pregnenolone, and their 17α-hydroxy-derivatives were used as substrates. After incubation, samples were analyzed using gas chromatography coupled to mass spectrometry. For progesterone and 17α-hydroxyprogesterone, their corresponding 21-hydroxylated metabolites 11-deoxycorticosterone and 11-deoxycortisol were detected, while after incubation of pregnenolone and 17α-hydroxypregnenolone, no hydroxylated product was observed. Findings were confirmed with authentic reference material. Molecular docking experiments agree with these results and suggest that interaction between the 3-oxo group and arginine-234 of the enzyme is a strict requirement. The presented results demonstrate once more that the presence of an oxo-group in position 3 of the steroid is indispensable, while a 3-hydroxy group prevents hydroxylation in position C-21 by CYP21A2. This knowledge may be transferred to other CYP21A2 substrates and hence help to gain essential insights into steroid metabolism.


Assuntos
Corticosteroides/metabolismo , Pregnenolona/farmacologia , Esteroide 21-Hidroxilase/metabolismo , 17-alfa-Hidroxipregnenolona/metabolismo , Domínio Catalítico , Sistema Enzimático do Citocromo P-450 , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxilação , Modelos Moleculares , Simulação de Acoplamento Molecular , Pregnenolona/metabolismo , Progesterona/metabolismo , Schizosaccharomyces , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroides/metabolismo , Especificidade por Substrato
6.
J Clin Endocrinol Metab ; 106(9): e3725-e3738, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-33822093

RESUMO

CONTEXT: Fetal zone steroids (FZSs) are excreted in high concentrations in preterm infants. Experimental data suggest protective effects of FZSs in models of neonatal disease. OBJECTIVE: We aimed to characterize the postnatal FZS metabolome of well preterm and term infants. METHODS: Twenty-four-hour urinary FZS excretion rates were determined in early preterm (<30 weeks' gestation), preterm (30-36 weeks), and term (>37 weeks) infants. Pregnenolone and 17-OH-pregnenolone metabolites (n = 5), and dehydroepiandrosterone sulfate and metabolites (n = 12) were measured by gas chromatography mass spectrometry. Postnatal concentrations of FZSs were compared with already published prenatal concentrations in amniotic fluid. RESULTS: Excretion rates of total FZSs and most of the single metabolites were highest in early preterm infants. In this group, excretion rates approach those of term infants at term equivalent postmenstrual age. Preterm infants of 30-36 weeks had more than half lower median excretion rates of FZSs than early preterm infants at the same time of postmenstrual age. Postnatal concentrations of FZSs were partly more than 100-fold higher in all gestational age groups than prenatal concentrations in amniotic fluid at midgestation. CONCLUSION: The excretion rates of FZSs as a proxy of the involution of the fetal zone of the most immature preterm infants approached those of term infants at term equivalent. In contrast, the fetal zone in more mature preterm infants undergoes more rapid involution. These data in exclusively well neonates can serve as a basis to investigate the effects of illness on the FZS metabolome in future studies.


Assuntos
Feto/metabolismo , Idade Gestacional , Recém-Nascido Prematuro/urina , Esteroides/urina , 17-alfa-Hidroxipregnenolona/urina , Adulto , Envelhecimento/metabolismo , Líquido Amniótico/química , Estudos de Coortes , Sulfato de Desidroepiandrosterona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente Extremamente Prematuro/urina , Recém-Nascido , Masculino , Gravidez , Pregnenolona/urina , Caracteres Sexuais
7.
PLoS One ; 15(12): e0244000, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33320886

RESUMO

The aim of this study was to investigate the potential interference of cyanobacterial metabolites, in particular microcystins (MCs), with steroid hormone biosynthesis. Steroid hormones control many fundamental processes in an organism, thus alteration of their tissue concentrations may affect normal homeostasis. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the modulation of 14 hormones involved in the adrenal steroid biosynthesis pathway using forskolin-treated H295R cells, following exposure with either microcystin-LR (MC-LR) alone, a mixture made up of MC-LR together with eight other MCs and nodularin-R (NOD-R), or extracts from the MC-LR-producing Microcystis aeruginosa PCC7806 strain or its MC-deficient mutant PCC7806mcyB-. Production of 17-hydroxypregnenolone and dehydroepiandrosterone (DHEA) was increased in the presence of MC-LR in a dose-dependent manner, indicating an inhibitory effect on 3ß-hydroxysteroid dehydrogenase (3ß-HSD). This effect was not observed following exposure with a MCs/NOD-R mixture, and thus the effect of MC-LR on 3ß-HSD appears to be stronger than for other congeners. Exposure to extracts from both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- had an opposite effect on 3ß-HSD, i.e. concentrations of pregnenolone, 17-hydroxypregnenolone and DHEA were significantly decreased, showing that there are other cyanobacterial metabolites that outcompete the effect of MC-LR, and possibly result instead in net-induction. Another finding was a possible concentration-dependent inhibition of CYP21A2 or CYP11ß1, which catalyse oxidation reactions leading to cortisol and cortisone, by MC-LR and the MCs/NOD-R mixture. However, both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- extracts had an opposite effect resulting in a substantial increase in cortisol levels. Our results suggest that MCs can modulate steroidogenesis, but the net effect of the M. aeruginosa metabolome on steroidogenesis is different from that of pure MC-LR and independent of MC production.


Assuntos
17-alfa-Hidroxipregnenolona/metabolismo , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Desidroepiandrosterona/biossíntese , Inibidores Enzimáticos/farmacologia , Microcistinas/farmacologia , Microcystis/química , Linhagem Celular Tumoral , Família 11 do Citocromo P450/antagonistas & inibidores , Família 21 do Citocromo P450/antagonistas & inibidores , Humanos
8.
J Steroid Biochem Mol Biol ; 197: 105538, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31734493

RESUMO

Measuring some sex and precursor steroids is still challenging even by liquid chromatography - tandem mass spectrometry (LC-MS/MS), and few normal values are available. We developed a LC-MS/MS method for estradiol, estrone, dihydrotestosterone and 17-hydroxypregnenolone measurement, compared it with direct immunoassays, and generated sex, age, menopausal and menstrual status specific reference intervals. Liquid-liquid extraction was optimized on 300 µL serum spiked with isotopic internal standards. A 2D-LC system allowed on-line purification and separation in 11 min run. Electrospray ionization was enhanced by ammonium fluoride. MS-detection was obtained by multiple reaction monitoring. Direct ECLIA for estradiol (n = 80) and RIA for estrone (n = 41) were compared with LC-MS/MS. Reference values were estimated in healthy, lean women in reproductive age (n = 118), menopausal women (n = 33) and men (n = 159). The assay showed satisfying imprecision, trueness, recovery and selectivity. Adequate functional sensitivity was achieved for measuring estrone (18.1 pmol/L) and 17-hydroxypregnenolone (117 pmol/L) in all subjects, and estradiol (35.9 pmol/L) and dihydrotestosterone (134 pmol/L) in women in reproductive age and men, but not in menopausal women. Compared with LC-MS/MS, immunoassays showed good agreement for estradiol but severe disagreement for estrone. Estrogens exhibited sex, menopausal and menstrual variations. Dihydrotestosterone and 17-hydroxypregnenolone depended on sex and menopause, the latter also declining with age in men. Strictly defined reference intervals in the adult female and male population were generated for challenging steroids such as estrogens, dihydrotestosterone and 17-hydroxypregnenolone by a novel LC-MS/MS method. Our achievement can be used to deepen the comprehension of several endocrine diseases.


Assuntos
17-alfa-Hidroxipregnenolona/sangue , Cromatografia Líquida/métodos , Di-Hidrotestosterona/sangue , Estradiol/sangue , Estrona/sangue , Espectrometria de Massas em Tandem/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
9.
Chemosphere ; 218: 328-339, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30476764

RESUMO

The presence of environmental pollutants in our ecosystem may impose harmful health effects to wildlife and humans. Several of these toxic chemicals have a potential to interfere with the endocrine system. The adrenal cortex has been identified as the main target organ affected by endocrine disrupting chemicals. The aim of this work was to assess exposure effects of defined and environmentally relevant mixtures of chlorinated, brominated and perfluorinated chemicals on steroidogenesis, using the H295R adrenocortical cell line model in combination with a newly developed liquid chromatography tandem mass spectrometry (LC-MS/MS) method. By using this approach, we could simultaneously analyze 19 of the steroids in the steroid biosynthesis pathway, revealing a deeper insight into possible disruption of steroidogenesis. Our results showed a noticeable down-regulation in steroid production when cells were exposed to the highest concentration of a mixture of brominated and fluorinated compounds (10,000-times human blood values). In contrast, up-regulation was observed with estrone under the same experimental condition, as well as with some other steroids when cells were exposed to a perfluorinated mixture (1000-times human blood values), and the mixture of chlorinated and fluorinated compounds. Interestingly, the low concentration of the perfluorinated mixture alone produced a significant, albeit small, down-regulation of pregnenolone, and the total mixture a similar effect on 17-hydroxypregnenolone. Other mixtures resulted in only slight deviations from the control. Indication of synergistic effects were noted when we used a statistical model to improve data interpretation. A potential for adverse outcomes of human exposures is indicated, pointing to the need for further investigation into these mixtures.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Esteroides/metabolismo , 17-alfa-Hidroxipregnenolona/metabolismo , Córtex Suprarrenal/efeitos dos fármacos , Córtex Suprarrenal/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Cromatografia Líquida , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Disruptores Endócrinos/administração & dosagem , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/administração & dosagem , Éteres Difenil Halogenados/toxicidade , Humanos , Metaboloma/efeitos dos fármacos , Modelos Estatísticos , Bifenilos Policlorados/toxicidade , Espectrometria de Massas em Tandem
10.
Sci Total Environ ; 610-611: 1164-1172, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28847137

RESUMO

A highly sensitive and robust method was developed for routine analysis of two progestin metabolites, 17α-hydroxypregnanolone (17OH-Δ5P) and pregnanediol (PD), and 31 other natural and synthetic steroids and related metabolites (estrogens, androgens, corticosteroids, progestins) in river water, as well as influents and effluents of municipal wastewater treatment plants (WWTP) using HPLC-MS/MS combined with solid-phase extraction. For the various matrixes considered, the optimized method showed satisfactory performance with recoveries of 70-120% for most of target steroids. The method detection limits (MDLs) ranged from 0.01 to 3ng/L for river water, 0.02 to 10ng/L for WWTP effluents, and 0.1 to 40ng/L for influents with good linearity and reproducibility. The developed method was successfully applied for the analysis of steroids in rivers and WWTP influent and effluents. WWTP influents concentrations of 17OH-Δ5P and PD were 51-256ng/L and up to 400ng/L, respectively, along with androstenedione (concentration range: 38-220ng/L), testosterone (11-26ng/L), estrone (2.3-37ng/L), 17ß-estradiol (N.D.-8.7ng/L), 17α-hydroxyprogesterone (N.D.-66ng/L), medroxyprogesterone acetate (N.D.-5.3ng/L), and progesterone (2.0-22ng/L), while only androstenedione (ADD), estrone (E1), and estriol (E3) were detected in effluent with concentrations ranging up to 1.7ng/L, 0.90ng/L and 0.8ng/L, respectively. In river water samples, only ADD and E1 were detected with concentrations up to 1.0ng/L and 0.91ng/L. Our procedure represents the first method for analyzing 17OH-Δ5P and PD in environmental samples along with a large series of steroids.


Assuntos
Cromatografia Líquida de Alta Pressão , Progestinas/análise , Rios/química , Esteroides/análise , Espectrometria de Massas em Tandem , Águas Residuárias/química , Poluentes Químicos da Água/análise , 17-alfa-Hidroxipregnenolona/análise , Corticosteroides/análise , Androgênios/análise , Estradiol/análise , Estriol/análise , Estrona/análise , Pregnanodiol/análise , Extração em Fase Sólida , Eliminação de Resíduos Líquidos
11.
J Biol Chem ; 292(32): 13168-13185, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28684414

RESUMO

Cytochrome P450 (P450, CYP) 17A1 plays a critical role in steroid metabolism, catalyzing both the 17α-hydroxylation of pregnenolone and progesterone and the subsequent 17α,20-lyase reactions to form dehydroepiandrosterone (DHEA) and androstenedione (Andro), respectively, critical for generating glucocorticoids and androgens. Human P450 17A1 reaction rates examined are enhanced by the accessory protein cytochrome b5 (b5), but the exact role of b5 in P450 17A1-catalyzed reactions is unclear as are several details of these reactions. Here, we examined in detail the processivity of the 17α-hydroxylation and lyase steps. b5 did not enhance reaction rates by decreasing the koff rates of any of the steroids. Steroid binding to P450 17A1 was more complex than a simple two-state system. Pre-steady-state experiments indicated lag phases for Andro production from progesterone and for DHEA from pregnenolone, indicating a distributive character of the enzyme. However, we observed processivity in pregnenolone/DHEA pulse-chase experiments. (S)-Orteronel was three times more inhibitory toward the conversion of 17α-hydroxypregnenolone to DHEA than toward the 17α-hydroxylation of pregnenolone. IC50 values for (S)-orteronel were identical for blocking DHEA formation from pregnenolone and for 17α-hydroxylation, suggestive of processivity. Global kinetic modeling helped assign sets of rate constants for individual or groups of reactions, indicating that human P450 17A1 is an inherently distributive enzyme but that some processivity is present, i.e. some of the 17α-OH pregnenolone formed from pregnenolone did not dissociate from P450 17A1 before conversion to DHEA. Our results also suggest multiple conformations of P450 17A1, as previously proposed on the basis of NMR spectroscopy and X-ray crystallography.


Assuntos
17-alfa-Hidroxipregnenolona/metabolismo , Citocromos b5/metabolismo , Desidroepiandrosterona/metabolismo , Modelos Moleculares , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Pregnenolona/metabolismo , Esteroide 17-alfa-Hidroxilase/metabolismo , 17-alfa-Hidroxipregnenolona/química , Androstenodiona/química , Androstenodiona/metabolismo , Animais , Sítios de Ligação , Biocatálise/efeitos dos fármacos , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Citocromos b5/genética , Desidroepiandrosterona/química , Humanos , Imidazóis/química , Imidazóis/metabolismo , Imidazóis/farmacologia , Cinética , Ligantes , NADPH-Ferri-Hemoproteína Redutase/genética , Naftalenos/química , Naftalenos/metabolismo , Naftalenos/farmacologia , Oxirredução , Pregnenolona/química , Progesterona/química , Progesterona/metabolismo , Conformação Proteica , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Esteroide 17-alfa-Hidroxilase/química , Esteroide 17-alfa-Hidroxilase/genética
12.
J Clin Endocrinol Metab ; 102(8): 2701-2710, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472487

RESUMO

Context: Patients with 21-hydroxylase deficiency (21OHD) have long-term complications, resulting from poor disease control and/or glucocorticoid overtreatment. Lack of optimal biomarkers has made it challenging to tailor therapy and predict long-term outcomes. Objective: To identify biomarkers of disease control and long-term complications in 21OHD. Setting and Participants: Cross-sectional study of 114 patients (70 males), ages 2 to 67 years (median, 15 years), seen in a tertiary referral center. Methods: We correlated a mass-spectrometry panel of 23 steroids, obtained before first morning medication, with bone age advancement (children), adrenal volume (adults), testicular adrenal rest tumors (TART), hirsutism, menstrual disorders, and pituitary hormones. Results: Total adrenal volume correlated positively with 18 steroids, most prominently 21-deoxycortisol and four 11-oxygenated-C19 (11oxC19) steroids: 11ß-hydroxyandrostenedione (11OHA4), 11-ketoandrostenedione (11ketoA4), 11ß-hydroxytestosterone (11OHT), and 11-ketotestosterone (11ketoT) (r ≈ 0.7, P < 0.0001). Nine steroids were significantly higher (P ≤ 0.01) in males with TART compared with those without TART, including 11OHA4 (6.8-fold), 11OHT (4.9-fold), 11ketoT (3.6-fold), 11ketoA4 (3.3-fold), and pregnenolone sulfate (PregS; 4.8-fold). PregS (28.5-fold) and 17-hydroxypregnenolone sulfate (19-fold) levels were higher (P < 0.01) in postpubertal females with menstrual disorders. In males, testosterone levels correlated positively with all 11oxC19 steroids in Tanner stages 1 and 2 (r ≈ 0.7; P < 0.001) but negatively in Tanner stage 5 (r = -0.3 and P < 0.05 for 11ketoA4 and 11ketoT). In females, testosterone level correlated positively with all four 11oxC19 steroids across all Tanner stages (r ≈ 0.8; P < 0.0001). Conclusion: 11oxC19 steroids and PregS might serve as clinically useful biomarkers of disease control and long-term complications in 21OHD.


Assuntos
Hiperplasia Suprarrenal Congênita/metabolismo , Tumor de Resto Suprarrenal/metabolismo , Androgênios/metabolismo , Hirsutismo/metabolismo , Distúrbios Menstruais/metabolismo , Neoplasias Testiculares/metabolismo , 17-alfa-Hidroxipregnenolona/análogos & derivados , 17-alfa-Hidroxipregnenolona/metabolismo , Adolescente , Glândulas Suprarrenais/patologia , Adulto , Determinação da Idade pelo Esqueleto , Idoso , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Androstenos/metabolismo , Criança , Pré-Escolar , Cortodoxona/metabolismo , Estudos Transversais , Feminino , Humanos , Hidroxitestosteronas/metabolismo , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pregnenolona/metabolismo , Testosterona/análogos & derivados , Testosterona/metabolismo , Adulto Jovem
13.
Nat Prod Res ; 31(20): 2435-2440, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28480737

RESUMO

Six pregnane steroids including one new compound namely 15ß-hydroxypregna-4,20-dien-3-one (1), were isolated and structurally elucidated from the octocoral Carijoa riisei. The cytotoxic activity against a panel of eight human cancer cell lines of isolated compounds was also evaluated by SRB method. As the results, 18-acetoxypregna-1,4,20-trien-3-one (5) showed significant cytotoxicity against all the tested cell lines with the IC50 values from 22.29 ± 1.47 to 48.73 ± 3.93 µM, whereas 15ß-acetoxypregna-1,4,20-trien-3-one (3) and 20R-acetoxypregna-1,4-dien-3-one (6) only exhibited weak effect on KB cell line with IC50 values of 93.62 ± 7.32 and 71.38 ± 5.45 µM, respectively.


Assuntos
17-alfa-Hidroxipregnenolona/isolamento & purificação , Antozoários/química , Pregnanos/química , Esteroides/química , 17-alfa-Hidroxipregnenolona/química , Animais , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Pregnanos/isolamento & purificação , Esteroides/isolamento & purificação , Vietnã
14.
Biomed Res Int ; 2017: 8182020, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28421200

RESUMO

Purpose. The aim of the present study was to elucidate the metabolic mechanisms associated with chronic fatigue syndrome (CFS) via an analysis of urine metabolites prior to and following exercise in a rat model. Methods. A rat model of CFS was established using restraint-stress, forced exercise, and crowded and noisy environments over a period of 4 weeks. Behavioral experiments were conducted in order to evaluate the model. Urine metabolites were analyzed via gas chromatography-mass spectrometry (GC-MS) in combination with multivariate statistical analysis before and after exercise. Results. A total of 20 metabolites were detected in CFS rats before and after exercise. Three metabolic pathways (TCA cycle; alanine, aspartate, and glutamate metabolism; steroid hormone biosynthesis) were significantly impacted before and after exercise, while sphingolipid metabolism alone exhibited significant alterations after exercise only. Conclusion. In addition to metabolic disturbances involving some energy substances, alterations in steroid hormone biosynthesis and sphingolipid metabolism were detected in CFS rats. Sphingosine and 21-hydroxypregnenolone may be key biomarkers of CFS, potentially offering evidence in support of immune dysfunction and hypothalamic-pituitary-adrenal (HPA) axis hypoactivity in patients with CFS.


Assuntos
17-alfa-Hidroxipregnenolona/urina , Síndrome de Fadiga Crônica/urina , Condicionamento Físico Animal , Esfingosina/urina , Aminoácidos/metabolismo , Animais , Comportamento Animal , Modelos Animais de Doenças , Síndrome de Fadiga Crônica/fisiopatologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hormônios Esteroides Gonadais/metabolismo , Humanos , Ratos , Ratos Sprague-Dawley
15.
Proc Natl Acad Sci U S A ; 112(52): 15856-61, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26668369

RESUMO

Ablation of androgen production through surgery is one strategy against prostate cancer, with the current focus placed on pharmaceutical intervention to restrict androgen synthesis selectively, an endeavor that could benefit from the enhanced understanding of enzymatic mechanisms that derives from characterization of key reaction intermediates. The multifunctional cytochrome P450 17A1 (CYP17A1) first catalyzes the typical hydroxylation of its primary substrate, pregnenolone (PREG) and then also orchestrates a remarkable C17-C20 bond cleavage (lyase) reaction, converting the 17-hydroxypregnenolone initial product to dehydroepiandrosterone, a process representing the first committed step in the biosynthesis of androgens. Now, we report the capture and structural characterization of intermediates produced during this lyase step: an initial peroxo-anion intermediate, poised for nucleophilic attack on the C20 position by a substrate-associated H-bond, and the crucial ferric peroxo-hemiacetal intermediate that precedes carbon-carbon (C-C) bond cleavage. These studies provide a rare glimpse at the actual structural determinants of a chemical transformation that carries profound physiological consequences.


Assuntos
17-alfa-Hidroxipregnenolona/metabolismo , Androgênios/metabolismo , Desidroepiandrosterona/metabolismo , Pregnenolona/metabolismo , Esteroide 17-alfa-Hidroxilase/metabolismo , 17-alfa-Hidroxipregnenolona/química , Androgênios/química , Biocatálise , Vias Biossintéticas , Desidroepiandrosterona/química , Humanos , Ligação de Hidrogênio , Hidroxilação , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Pregnenolona/química , Conformação Proteica , Espectrofotometria/métodos , Esteroide 17-alfa-Hidroxilase/química , Esteroide 17-alfa-Hidroxilase/genética , Especificidade por Substrato , Temperatura
16.
Endocrinology ; 156(7): 2646-56, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25942073

RESUMO

Urocortin 2 (UCN2) is a neuropeptide of the CRH family, involved in homeostatic mechanisms, the stress response, and control of anxiety. To elucidate the effects of UCN2 on steroidogenesis, we developed a mouse model that allows a Cre recombinase-determined conditional overexpression of UCN2 (UCN2-COE). In these mice SF1-Cre-driven overexpression of UCN2 was restricted to the adrenal glands, gonads, and parts of the hypothalamus. UCN2-COE animals of both sexes revealed significantly higher plasma UCN2 levels and significantly higher UCN2 expression levels in the adrenals and ovaries. In contrast, the baseline expression of UCN2 was already high in the testes of control mice with no further increase achievable in UCN2-COE animals. Adrenal steroidogenesis of UCN2-COE animals was investigated under baseline conditions, upon an ACTH stimulation test, and following a restraint stress test. A tendency toward lower expression of steroidogenic enzymes was detectable in UCN2-COE animals of both sexes with slight differences between males and females. A similar reduction in the expression levels of the final steps of ovarian steroidogenesis, accompanied by reduced plasma estradiol levels, was observed in female UCN2-COE animals. Thus, adrenal UCN2 overexpression resulted in down-regulation of adrenal steroidogenesis, suggesting a reduction in the stress response in the mouse (stress coping behavior). Similarly, UCN2 overexpression in the ovaries caused a decrease in steroidogenesis and reduction of follicles that had undergone ovulation. Nevertheless, this finding was not associated with reduced fertility.


Assuntos
Glândulas Suprarrenais/metabolismo , Hormônio Liberador da Corticotropina/genética , Ovário/metabolismo , RNA Mensageiro/metabolismo , Urocortinas/genética , 17-Hidroxiesteroide Desidrogenases/genética , 17-alfa-Hidroxipregnenolona/metabolismo , 3-Hidroxiesteroide Desidrogenases/efeitos dos fármacos , 3-Hidroxiesteroide Desidrogenases/genética , Glândulas Suprarrenais/efeitos dos fármacos , Hormônio Adrenocorticotrópico/farmacologia , Animais , Aromatase/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/efeitos dos fármacos , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Citocromo P-450 CYP11B2/efeitos dos fármacos , Citocromo P-450 CYP11B2/genética , Estradiol/metabolismo , Feminino , Técnicas de Introdução de Genes , Hormônios Esteroides Gonadais , Masculino , Camundongos , Ovário/anatomia & histologia , Fenótipo , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/genética , Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esteroide 11-beta-Hidroxilase/efeitos dos fármacos , Esteroide 11-beta-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/genética , Testículo/metabolismo
17.
PLoS One ; 10(3): e0120473, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785994

RESUMO

Neurosteroids can modulate the activity of the GABAA receptors, and thus affect anxiety-like behaviors. The non-benzodiazepine anxiolytic compound etifoxine has been shown to increase neurosteroid concentrations in brain tissue but the mode of action of etifoxine on neurosteroid formation has not yet been elucidated. In the present study, we have thus investigated the effect and the mechanism of action of etifoxine on neurosteroid biosynthesis using the frog hypothalamus as an experimental model. Exposure of frog hypothalamic explants to graded concentrations of etifoxine produced a dose-dependent increase in the biosynthesis of 17-hydroxypregnenolone, dehydroepiandrosterone, progesterone and tetrahydroprogesterone, associated with a decrease in the production of dihydroprogesterone. Time-course experiments revealed that a 15-min incubation of hypothalamic explants with etifoxine was sufficient to induce a robust increase in neurosteroid synthesis, suggesting that etifoxine activates steroidogenic enzymes at a post-translational level. Etifoxine-evoked neurosteroid biosynthesis was not affected by the central-type benzodiazepine (CBR) receptor antagonist flumazenil, the translocator protein (TSPO) antagonist PK11195 or the GABAA receptor antagonist bicuculline. In addition, the stimulatory effects of etifoxine and the triakontatetraneuropeptide TTN, a TSPO agonist, were additive, indicating that these two compounds act through distinct mechanisms. Etifoxine also induced a rapid stimulation of neurosteroid biosynthesis from frog hypothalamus homogenates, a preparation in which membrane receptor signalling is disrupted. In conclusion, the present study demonstrates that etifoxine stimulates neurosteroid production through a membrane receptor-independent mechanism.


Assuntos
17-alfa-Hidroxipregnenolona/agonistas , Ansiolíticos/farmacologia , Desidroepiandrosterona/agonistas , Hipotálamo/efeitos dos fármacos , Oxazinas/farmacologia , Pregnanolona/agonistas , Progesterona/agonistas , 17-alfa-Hidroxipregnenolona/metabolismo , 20-alfa-Di-Hidroprogesterona/antagonistas & inibidores , 20-alfa-Di-Hidroprogesterona/biossíntese , Animais , Bicuculina/farmacologia , Misturas Complexas/química , Desidroepiandrosterona/biossíntese , Relação Dose-Resposta a Droga , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Antagonistas de Receptores de GABA-A/farmacologia , Expressão Gênica , Hipotálamo/metabolismo , Isoquinolinas/farmacologia , Masculino , Neuropeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Pregnanolona/biossíntese , Progesterona/biossíntese , Rana esculenta , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Técnicas de Cultura de Tecidos
18.
Hum Reprod ; 29(12): 2764-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25336708

RESUMO

STUDY QUESTION: Are there abnormalities in gonadotrophin secretion, adrenal steroidogenesis and/or testicular steroidogenesis in brothers of women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Brothers of women with PCOS have increased gonadotrophin responses to gonadotrophin releasing hormone (GnRH) agonist stimulation and alterations in adrenal and gonadal steroidogenesis. WHAT IS KNOWN ALREADY: PCOS is a complex genetic disease. Male as well as female first-degree relatives have reproductive features of the syndrome. We previously reported that brothers of affected women have elevated circulating dehydroepiandrosterone sulfate levels. STUDY DESIGN, SIZE, DURATION: This was a case-control study performed in 29 non-Hispanic white brothers of 22 women with PCOS and 18 control men. PARTICIPANTS/MATERIALS, SETTING, METHODS: PCOS brothers and control men were of comparable age, weight and ethnicity. Adrenocorticotrophic hormone (ACTH) and GnRH agonist stimulation tests were performed. Gonadotrophin responses to GnRH agonist as well as changes in precursor-product steroid pairs (delta, Δ) across steroidogenic pathways in response to ACTH and GnRH agonist were examined. MAIN RESULTS AND THE ROLE OF CHANCE: Basal total (T) levels did not differ, but dehydroepiandrosterone (DHEA) levels (0.13 ± 0.08 brothers versus 0.22 ± 0.09 controls, nmol/l, P = 0.03) were lower in brothers compared with control men. ACTH-stimulated Δ17-hydroxypregnenolone (17Preg)/Δ17-hydroxyprogesterone (17Prog) (7.8 ± 24.2 brothers versus 18.9 ± 21.3 controls, P = 0.04) and ΔDHEA/Δandrostenedione (AD) (0.10 ± 0.05 brothers versus 0.14 ± 0.08 controls, P = 0.04) were lower in brothers than in the controls. GnRH agonist-stimulated Δ17Prog/ΔAD (0.28 ± 8.47 brothers versus 4.79 ± 10.28 controls, P = 0.003) was decreased and luteinizing hormone (38.6 ± 20.6 brothers versus 26.0 ± 9.8 controls, IU/l, P = 0.02), follicle-stimulating hormone (10.2 ± 7.5 brothers versus 4.8 ± 4.1 controls, IU/l P = 0.002), AD (1.7 ± 1.4 brothers versus 0.9 ± 1.5 controls, nmol/l, P = 0.02) and ΔAD/ΔT (0.16 ± 0.14 brothers versus 0.08 ± 0.12 controls, P = 0.005) responses were increased in brothers compared with controls. LIMITATIONS, REASONS FOR CAUTION: The modest sample size may have limited our ability to observe other possible differences in steroidogenesis between PCOS brothers and control men. WIDER IMPLICATIONS OF THE FINDINGS: Decreased ACTH-stimulated Δ17Preg/Δ17Prog and ΔDHEA/ΔAD responses suggested increased adrenal 3ß-hydroxysteroid dehydrogenase activity in the brothers. Decreased Δ17Prog/ΔAD and increased ΔAD/ΔT responses to GnRH agonist stimulation suggested increased gonadal 17,20-lyase and decreased gonadal 17ß-hydroxysteroid dehydrogenase activity in the brothers. Increased LH and FSH responses to GnRH agonist stimulation suggested neuroendocrine alterations in the regulation of gonadotrophin secretion similar to those in their proband sisters. These changes in PCOS brothers may reflect the impact of PCOS susceptibility genes and/or programming effects of the intrauterine environment. STUDY FUNDING/COMPETING INTERESTS: This research was supported by P50 HD044405 (A.D.), K12 HD055884 (L.C.T.), U54 HD034449 (A.D., R.S.L.) from the National Institute of Child Health and Development. Some hormone assays were performed at the University of Virginia Center for Research in Reproduction Ligand Assay and Analysis Core that is supported by U54 HD28934 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Partial support for some of the clinical studies was provided by UL1 RR025741 and UL1 TR000150 (Northwestern University Clinical and Translational Sciences Institute) from the National Center for Research Resources, National Institutes of Health, which is now the National Center for Advancing Translational Sciences. The authors have no conflict of interest to declare.


Assuntos
Gonadotropinas/sangue , Síndrome do Ovário Policístico , Esteroides/sangue , 17-alfa-Hidroxipregnenolona/sangue , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Adulto , Androstenodiona/sangue , Estudos de Casos e Controles , Cortodoxona/sangue , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Irmãos
19.
Artigo em Inglês | MEDLINE | ID: mdl-24239668

RESUMO

While there have been a number of studies on the effects of photoperiod and duration of light and dark exposure, much less information is available on the importance of light intensity. This study investigated the effects of exposure of goldfish, Carassius auratus exposed to white fluorescent bulbs, and red (peak at 630nm), and green (530nm) light emitting diodes (LEDs) at approximately 0.9W/m(2) (12-h light:12-h dark) for four months on a number of hormones of the hypothalamus-pituitary-gonad (HPG) axis, in vivo and in vitro. We investigated the effects of native GnRH molecules (gonadotropin-releasing hormones; salmon GnRH, sGnRH; and chicken GnRH-II, cGnRH-II), gonadotropin hormones (GTHα; follicle-stimulating hormone, FSH-ß; luteinizing hormone, LH-ß2), kisspeptin 1 (Kiss1) and G protein-coupled receptor 54 (GPR54) mRNA levels. Furthermore, we measured LH and 17α-hydroxypregnenolone levels in plasma and we performed gonad histological observations. GnRHs, Kiss1, GPR54 and GTH mRNA and plasma LH and 17α-hydroxypregnenolone levels in the in vivo and in vitro groups exposed to green LEDs were significantly higher than the other groups. Histological analysis revealed the presence of oocytes in the yolk stage in fish exposed to green light. These results suggest that green wavelengths regulate the HPG axis and enhance sexual maturation in goldfish.


Assuntos
Carpa Dourada/crescimento & desenvolvimento , Luz , Ovário/metabolismo , 17-alfa-Hidroxipregnenolona/sangue , Animais , Células Cultivadas , Feminino , Proteínas de Peixes/sangue , Proteínas de Peixes/genética , Expressão Gênica , Hormônio Liberador de Gonadotropina/fisiologia , Gonadotropinas/sangue , Crescimento e Desenvolvimento/efeitos da radiação , Sistema Hipotálamo-Hipofisário , Hipotálamo/citologia , Hipotálamo/metabolismo , Kisspeptinas/sangue , Kisspeptinas/genética , Hormônio Luteinizante/sangue , Ovário/citologia , Ovário/crescimento & desenvolvimento , Receptores de Galanina/genética , Receptores de Galanina/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-24239680

RESUMO

Kisspeptins (Kiss) have been recognized as potent regulators of reproduction in teleosts, and Kiss is suggested to be a key regulator of the hypothalamus-pituitary-gonad axis (HPG). However, its regulatory role on reproduction in fish remains unclear. Therefore, to investigate the role of Kiss on fish reproduction, this study aimed to test differences in the hormones of the HPG axis, Kiss as neuropeptides, and sex steroids on the sexual maturation of paired cinnamon clownfish, Amphiprion melanopus, following treatment with Kiss. We investigated the actions of sex maturation hormones, including HPG axis hormones and sex steroid hormones, such as gonadotropin-releasing hormones, gonadotropin hormones (GTHs), GTH receptors, estrogen receptors, and vitellogenin in the pituitary, gonads, and liver following treatment with Kiss. The expression levels of HPG axis genes increased after the Kiss injection. In addition, the levels of plasma 17α-hydroxypregnenolone, estradiol-17ß, and 11-ketotestosterone increased. These results support the hypothesis that Kiss play important roles in the regulation of the HPG axis and are most likely involved in gonadal development and sexual maturation in cinnamon clownfish.


Assuntos
Peixes/metabolismo , Gônadas/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Kisspeptinas/metabolismo , Maturidade Sexual , 17-alfa-Hidroxipregnenolona/sangue , Animais , Estradiol/sangue , Feminino , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Gonadotropinas/genética , Gonadotropinas/metabolismo , Masculino , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores da Gonadotropina/genética , Receptores da Gonadotropina/metabolismo , Testosterona/análogos & derivados , Testosterona/sangue
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