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1.
Sex Dev ; 12(1-3): 30-40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28850950

RESUMO

Commonly known for testosterone secretion, the testes also produce the protein hormones anti-müllerian hormone (AMH), inhibin B, and insulin-like factor 3 (INSL3). AMH and inhibin B are secreted by Sertoli cells, whereas INSL3 is a Leydig cell product. AMH is involved in fetal sex differentiation and induces the regression of the anlagen of the uterus and fallopian tubes. INSL3 participates in fetal testicular descent. Serum testicular protein hormone assessment can be very useful and complementary to testosterone measurements in patients with DSD. AMH and inhibin B determination is extremely helpful during childhood, when basal testosterone is normally low. Serum AMH and inhibin B above the female range are indicative of the presence of testicular tissue, and their circulating levels reflect the amount of functional Sertoli cells. In DSD patients with normal male levels of AMH and inhibin B, the diagnosis of gonadal dysgenesis can be ruled out, and isolated androgen secretion deficiency or androgen insensitivity should be suspected. In externally virilized XY patients with persistent müllerian ducts, serum AMH levels determine the diagnosis to AMH deficiency or resistance. At pubertal age, inhibin B levels serve to predict spermatogenic development.


Assuntos
Transtornos do Desenvolvimento Sexual/sangue , Transtornos do Desenvolvimento Sexual/diagnóstico , Hormônios Testiculares/sangue , Transtornos do Desenvolvimento Sexual/fisiopatologia , Feto/metabolismo , Humanos , Diferenciação Sexual
2.
J Clin Endocrinol Metab ; 92(7): 2739-43, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17488788

RESUMO

CONTEXT: We have previously observed increased anti-Müllerian hormone (AMH) levels in prepubertal daughters of polycystic ovary syndrome (PCOS) women, suggesting that these girls may have an altered follicular development. However, it is not known whether AMH levels remain increased during puberty. OBJECTIVE: The aim was to establish whether the increased AMH levels observed in prepubertal daughters of PCOS women persist during the peripubertal period, a stage during which the gonadal axis is activated and PCOS may become clinically manifested. DESIGN: We studied 28 daughters (8-16 yr old) of PCOS women (PCOSd) and 33 daughters (8-16 yr old) of control women (Cd). In both groups, an oral glucose tolerance test was performed. Gonadotropins, sex hormones, and AMH were determined in a fasting sample. RESULTS: Both groups were comparable in age, body mass index, and breast Tanner stage. Free androgen index, testosterone, AMH (Cd 14.4 +/- 8.0 pM vs. PCOSd 24.0 +/- 19.0 pM; P = 0.012), and 2-h insulin levels were significantly higher in the PCOSd group compared with the control group. The average ovarian volume was significantly higher in the PCOSd group. In both groups a positive correlation between 2-h insulin and AMH concentrations was observed (PCOSd: r = 0.530, P = 0.007; Cd: r =0.561, P = 0.008). CONCLUSIONS: AMH concentrations are increased in peripubertal PCOSd. These findings, along with the results of our previous study, suggest that PCOSd appear to show an increased follicular mass that is established during early development, and persists during puberty.


Assuntos
Glicoproteínas/sangue , Menarca/sangue , Síndrome do Ovário Policístico/diagnóstico , Puberdade/fisiologia , Hormônios Testiculares/sangue , Adolescente , Hormônio Antimülleriano , Criança , Diagnóstico Precoce , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Núcleo Familiar , Ovário/metabolismo , Ovário/patologia , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/genética
3.
J Clin Endocrinol Metab ; 91(10): 4092-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16849404

RESUMO

CONTEXT: Newborns with ambiguous genitalia or males with nonpalpable gonads usually require an early assessment of the presence and functional state of testicular tissue. OBJECTIVE: Our objective was to characterize the precise ontogeny of the serum patterns of gonadotropins, testosterone, anti-Müllerian hormone (AMH), and inhibins in normal newborn boys. DESIGN: We conducted a cross-sectional and longitudinal study. SUBJECTS: Serum samples were obtained in 57 boys and 13 girls on d 2 of life. A second sample was obtained on d 7, 10, 15, 20, and 30 (boys) and on d 30 (girls). MAIN OUTCOME MEASURES: Serum levels of gonadotropins, testosterone, AMH, and inhibins were measured. RESULTS: In males, LH and FSH were undetectable or very low on d 2. By d 7, LH increased to 3.94 +/- 3.19 IU/liter (mean +/- sd) and FSH to 2.04 +/- 1.67 IU/liter. LH/FSH ratios were 0.40 +/- 0.11 (d 2) and 2.02 +/- 0.20 (d 30). AMH rose from 371 +/- 168 pmol/liter (d 2) to 699 +/- 245 pmol/liter (d 30), and inhibin B rose from 214 +/- 86 ng/liter (d 2) to 361 +/- 93 ng/liter (d 30). The inhibin alpha-subunit precursor (pro-alphaC) remained stable during the first month of life. Testosterone levels were 66 +/- 42 ng/dl (d 2), 82 +/- 24 ng/dl (d 20), and 210 +/- 130 ng/dl (d 30). A sexual dimorphism was observed in AMH and inhibin B (lower in girls on d 2 and 30), in LH/FSH ratio (lower in girls on d 30) and in testosterone (lower in girls on d 30). CONCLUSIONS: Sertoli cell markers AMH and inhibin B are the earliest useful markers indicating the existence of normal testicular tissue.


Assuntos
Hormônio Foliculoestimulante/sangue , Glicoproteínas/sangue , Inibinas/sangue , Hormônio Luteinizante/sangue , Precursores de Proteínas/sangue , Hormônios Testiculares/sangue , Hormônio Antimülleriano , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Testosterona/sangue
4.
J Clin Endocrinol Metab ; 91(8): 3105-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16720659

RESUMO

CONTEXT: Anti-Müllerian hormone (AMH) is produced by the granulosa cells and reflects follicular development. Adult women with polycystic ovary syndrome (PCOS) have increased levels of AMH associated with an excessive number of growing follicles. However, it is not known whether these abnormalities are present before the clinical onset of PCOS. OBJECTIVE: Our objective was to investigate whether prepubertal daughters of women with PCOS have increased AMH levels. DESIGN: Fourteen female infants (2-3 months old) and 25 prepubertal girls (4-7 yr old) born to PCOS mothers were studied. As a control group, we studied 21 female infants and 24 prepubertal girls born to mothers with regular menses and without hyperandrogenism. The group with PCOS mothers and the control group had normal birth weight and were born from spontaneous singleton pregnancies. Circulating concentrations of gonadotropins, testosterone, androstenedione, estradiol, 17-OH-progesterone, SHBG, inhibin B, and AMH were determined by specific assays. RESULTS: Serum concentrations of AMH were significantly higher in the PCOS group compared with the control group during early infancy (20.4 +/- 15.6 vs. 9.16 +/- 8.6 pmol/liter; P = 0.024) and during childhood (14.8 +/- 7.7 vs. 9.61 +/- 4.4 pmol/liter; P = 0.007). Gonadotropin and serum sex steroid concentrations were similar in both groups during the two study periods, except for FSH, which was lower during childhood in girls born to PCOS mothers. CONCLUSIONS: We conclude that serum AMH concentrations are increased in prepubertal daughters of PCOS women, suggesting that these girls appear to show evidence of an altered follicular development during infancy and childhood.


Assuntos
Glicoproteínas/sangue , Síndrome do Ovário Policístico/sangue , Puberdade/sangue , Hormônios Testiculares/sangue , 17-alfa-Hidroxiprogesterona/sangue , Androstenodiona/sangue , Hormônio Antimülleriano , Criança , Pré-Escolar , Meio Ambiente , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Gonadotropinas/sangue , Humanos , Lactente , Inibinas/sangue , Síndrome do Ovário Policístico/etiologia , Síndrome do Ovário Policístico/genética , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue
5.
J Clin Endocrinol Metab ; 90(11): 6035-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16131574

RESUMO

CONTEXT: Isolated hypospadias may result from impaired testicular function or androgen end-organ defects or, alternatively, from hormone-independent abnormalities of morphogenetic events responsible for urethral seam. OBJECTIVE: The objective was to evaluate the relative prevalence of hormone-dependent etiologies in boys with isolated hypospadias. DESIGN, PATIENTS, AND MAIN OUTCOME MEASURES: We studied endocrine testicular capacity in 61 patients with isolated hypospadias and 28 with hypospadias associated with micropenis, cryptorchidism, or ambiguous genitalia. Serum anti-Müllerian hormone and inhibin B were used as Sertoli cell markers. A human chorionic gonadotropin test was performed to evaluate Leydig cell function. RESULTS: Testicular dysfunction was observed in 57.1% and androgen end-organ defects in 7.2% of patients with hypospadias associated with cryptorchidism, micropenis, or ambiguous genitalia. In the remaining 35.7%, the disorder was idiopathic. The presence of ambiguous genitalia predicted the existence of testicular or end-organ dysfunction with 81.8% specificity. Isolated hypospadias was associated in 14.8% of patients with testicular dysfunction and in 6.5% of cases with end-organ defects; in 78.7% of cases, the condition was idiopathic. The occurrence of isolated hypospadias ruled out the existence of testicular or end-organ disorders with 80.0% sensitivity. Altogether our data indicate that the risk for the existence of an underlying testicular or end-organ dysfunction is low in patients with isolated hypospadias (odds ratio, 0.13; 95% confidence interval, 0.05-0.36; P < 0.001). CONCLUSIONS: Boys with isolated hypospadias are more likely to have normal endocrine testicular and androgen end-organ functions, suggesting that transient disruption of morphogenetic events in early fetal life may be the predominant underlying cause.


Assuntos
Hipospadia/fisiopatologia , Células Intersticiais do Testículo/fisiologia , Células de Sertoli/fisiologia , Testículo/fisiopatologia , Hormônio Antimülleriano , Gonadotropina Coriônica/farmacologia , Di-Hidrotestosterona/sangue , Glicoproteínas/sangue , Humanos , Hipospadia/etiologia , Masculino , Risco , Hormônios Testiculares/sangue , Testosterona/sangue , Uretra/embriologia
6.
Clin Endocrinol (Oxf) ; 60(6): 758-64, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15163341

RESUMO

OBJECTIVE: Anti-Müllerian hormone (AMH) and inhibin B are reliable markers of Sertoli cell function. The aim of the present study was to assess the functional state of Sertoli cells in order to detect early changes in the testicular function of prepubertal and pubertal patients with untreated grade II or III varicocele. DESIGN AND PATIENTS: Seven prepubertal and 55 pubertal boys with untreated grade II or III varicocele were studied. Seven prepubertal and 43 pubertal normal boys were considered as controls. MEASUREMENTS: Serum levels of gonadotrophins, testosterone, inhibin B and Pro-alphaC and AMH were determined by time-resolved immunofluorometric assays, radioimmunoassay (RIA) and specific enzyme-linked immunosorbent assays (ELISAs), respectively. RESULTS: Inhibin B and Pro-alphaC serum levels were higher in prepubertal patients with varicocele than in controls (P < 0.001). No further increment in inhibin B and Pro-alphaC levels was observed in pubertal patients with varicocele. Higher levels of AMH were found in patients in Tanner stages I, III, IV and V when compared to normal boys by Tanner stage (P < 0.05, P < 0.01, P < 0.01, P < 0.001, respectively). The direct correlation found in normal boys between inhibin B levels and LH, testosterone and testicular volume was not observed in patients with varicocele. CONCLUSIONS: The altered serum profile of gonadal hormones observed in untreated prepubertal and pubertal patients with varicocele may indicate an early abnormal regulation of the seminiferous epithelium function.


Assuntos
Glicoproteínas/sangue , Inibinas/sangue , Precursores de Proteínas/sangue , Puberdade/sangue , Hormônios Testiculares/sangue , Varicocele/sangue , Adolescente , Adulto , Hormônio Antimülleriano , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Estudos Transversais , Humanos , Hormônio Luteinizante/sangue , Masculino , Células de Sertoli/metabolismo , Testículo/anatomia & histologia , Testosterona/sangue , Varicocele/fisiopatologia
7.
J Pediatr Endocrinol Metab ; 16(3): 357-64, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12705358

RESUMO

In normal clinical practice, testicular evaluation in boys has relied on palpation and testosterone determination after hCG stimulation, which reflects the activity of interstitial Leydig cells. However, the most active compartment of the testis before puberty is the seminiferous tubule compartment, in which Sertoli cells proliferate and secrete anti-Müllerian hormone (AMH) and inhibin B. The recent development of commercially available assays for these two peptides has provided the pediatrician with excellent tools to assess the existence of functional testicular tissue in boys with no need for hCG stimulation. Serum AMH determination is also useful to assess testicular tissue mass and function in patients with intersex disorders. The determination of testosterone, its precursors and dihydrotestosterone, after hCG stimulation, should be reserved for situations in which Leydig cell function needs to be specifically assessed.


Assuntos
Gonadotropina Coriônica/metabolismo , Criptorquidismo/diagnóstico , Transtornos do Desenvolvimento Sexual/diagnóstico , Glicoproteínas , Inibidores do Crescimento/sangue , Inibinas/sangue , Células de Sertoli/metabolismo , Hormônios Testiculares/sangue , Adolescente , Hormônio Antimülleriano , Biomarcadores/sangue , Criança , Pré-Escolar , Criptorquidismo/fisiopatologia , Humanos , Masculino , Túbulos Seminíferos/citologia , Túbulos Seminíferos/metabolismo , Testículo/citologia , Testículo/metabolismo
8.
Am J Surg Pathol ; 25(10): 1237-44, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11688457

RESUMO

We report on six boys with intratubular Sertoli cell proliferations (ISCPs), studied by routine histologic methods, electron microscopy, and immunohistochemistry of anti-müllerian hormone (AMH), inhibin alpha-subunit, 3beta-hydroxysteroid dehydrogenase (3beta-HSD), proliferative cellular nuclear antigen, and p53, and carefully followed for extended periods with periodic clinical examinations, testicular ultrasonographies, and determinations of serum levels of AMH and inhibin B. Peutz-Jeghers syndrome was found in four of six patients, and gynecomastia occurred in five of six patients. One boy had isosexual pseudoprecocity. ISCPs were observed as multiple foci of seminiferous tubules with large and proliferated Sertoli cells replacing germ cells and limited by the basement membrane. Mitotic figures, atypia, and/or interstitial invasion were not observed. Bilateral ISCPs were the only pathologic finding in three patients (patient nos. 1-3) and were associated with a microscopic tumor that resembled a large-cell calcifying Sertoli cell tumor (LCCSCT) in a fourth patient (patient no. 4). In the two remaining patients (patient nos. 5 and 6) ISCPs and LCCSCT were found in both testes. Ultrastructural examination showed large Sertoli cells, with round nuclei, sparse organelles, and some glycogen. Inhibin alpha-subunit immunolocalization was positive in the five patients in whom it was determined (patient nos. 2-6), AMH was positive in those ISCPs associated with tumors (patient nos. 4-6) and negative in isolated ISCPs (patient nos. 2 and 3); 3beta-HSD and PCNA were variable, and p53 was negative in all ISCPs. Patient nos. 1-4 have been followed for 2-19 years. One of them is currently entering puberty, the other two have already completed puberty and have testes of normal size, and the remaining one is an adult with clinically normal testes and sperm production. None of these patients had evidence of tumor development during follow-up as shown by serial ultrasonographies and serum levels of AMH and inhibin B. Patient nos. 5 and 6 who had bilateral ISCPs and LCCSCT were orchidectomized and evolved for 2-10 years after surgery without tumor recurrence. The prognostic significance of ISCPs, particularly when they are the only pathologic finding in a testicular biopsy, is a matter of controversy. Based on the long normal evolution, we recommend a conservative approach to therapy. The bilateral and multicentric character of ISCPs and their association with Sertoli tumors and Peutz-Jeghers syndrome suggest that they represent either proliferative lesions with tumorigenic potential or the intraepithelial stage in the evolution of some testicular Sertoli cell tumors.


Assuntos
Glicoproteínas , Lesões Pré-Cancerosas/patologia , Tumor de Células de Sertoli/patologia , Células de Sertoli/patologia , Neoplasias Testiculares/patologia , 3-Hidroxiesteroide Desidrogenases/análise , Adolescente , Hormônio Antimülleriano , Divisão Celular , Criança , Seguimentos , Inibidores do Crescimento/sangue , Humanos , Inibinas/análise , Inibinas/sangue , Masculino , Síndrome de Peutz-Jeghers/patologia , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/química , Lesões Pré-Cancerosas/diagnóstico por imagem , Antígeno Nuclear de Célula em Proliferação/análise , Tumor de Células de Sertoli/sangue , Tumor de Células de Sertoli/química , Tumor de Células de Sertoli/diagnóstico por imagem , Células de Sertoli/química , Hormônios Testiculares/sangue , Neoplasias Testiculares/sangue , Neoplasias Testiculares/química , Neoplasias Testiculares/diagnóstico por imagem , Proteína Supressora de Tumor p53/análise , Ultrassonografia
9.
Artigo em Inglês | MEDLINE | ID: mdl-11097782

RESUMO

Anti-müllerian hormone (AMH) is specifically produced by Sertoli cells in the male. The testes express a high level of AMH from early fetal life, driven by the transcription factors SOX9, SF1, WT1 and GATA4, until puberty, when AMH is downregulated by testosterone and meiosis. When androgen negative effect is absent, follicle-stimulating hormone increases the secretion of AMH. Serum AMH determination is useful in the evaluation of children with non-palpable gonads, with or without ambiguous genitalia. It signals the existence of functional testicular tissue and allows a distinction to be made between gonadal dysgenesis and dissociated tubular-interstitial dysfunction. Serum AMH is a useful marker in the follow-up of male patients with precocious puberty or hypogonadotrophic hypogonadism, as well as of patients with sex cord stromal tumours of the gonads. Finally, AMH determination on the seminal plasma of men with non-obstructive azoospermia may be used as a marker of the existence of testicular spermatozoa when intracytoplasmic sperm injection is considered.


Assuntos
Glicoproteínas , Inibidores do Crescimento/fisiologia , Túbulos Seminíferos/fisiologia , Hormônios Testiculares/fisiologia , Hormônio Antimülleriano , Doenças dos Genitais Masculinos/sangue , Doenças dos Genitais Masculinos/diagnóstico , Inibidores do Crescimento/sangue , Inibidores do Crescimento/metabolismo , Humanos , Masculino , Sêmen/metabolismo , Hormônios Testiculares/sangue , Hormônios Testiculares/metabolismo
10.
J Pediatr Endocrinol Metab ; 13(6): 605-12, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10905384

RESUMO

Investigation of the origin of sexual ambiguity is complex. Although testicular function has traditionally been assessed only by examining the steroidogenic capacity of Leydig cells and spermatogenesis, it has recently been shown that the measurement of serum anti-Müllerian hormone (AMH) as a marker of Sertoli cell function may also help clinicians. The aim of this study was to evaluate both Leydig and Sertoli cell functions in 46,XY patients with intersex states in order to establish biochemical patterns that would help to reach an etiologic diagnosis. We measured serum androgens, AMH and gonadotropins in 24 patients with sexual ambiguity and XY karyotype: 8 with gonadal dysgenesis (GD), 3 with 3beta-hydroxysteroid dehydrogenase deficiency (3betaHSD), 5 with androgen insensitivity syndrome (AIS), 4 with 5alpha-reductase 2 (SRD5A2) deficiency, and 4 were of unknown origin or idiopathic. Our results showed that while testosterone was low and gonadotropins elevated in patients with either GD or 3betaHSD, AMH was low in the former and high in the latter. Serum AMH and gonadotropins were normal or high in patients with 3betaHSD or AIS, but these could be distinguished by testosterone levels. Serum testosterone and gonadotropins were normal or high in AIS and SRD5A2 deficiency patients; however, while AMH was elevated in AIS, it was not the case in SRD5A2 deficiency patients, indicating that testosterone is sufficient to inhibit AMH within the testis. In idiopathic cases gonadotropins and testosterone were normal, and AMH was normal or low. We conclude that the combined measurement of androgens, AMH and gonadotropins helps to establish the diagnosis in intersex patients.


Assuntos
Transtornos do Desenvolvimento Sexual/fisiopatologia , Glicoproteínas , Testículo/fisiopatologia , 3-Hidroxiesteroide Desidrogenases/deficiência , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/deficiência , Adolescente , Síndrome de Resistência a Andrógenos/fisiopatologia , Hormônio Antimülleriano , Criança , Pré-Escolar , Gonadotropina Coriônica/farmacologia , Hormônio Foliculoestimulante/sangue , Disgenesia Gonadal/fisiopatologia , Inibidores do Crescimento/sangue , Humanos , Lactente , Cariotipagem , Células Intersticiais do Testículo/fisiologia , Hormônio Luteinizante/sangue , Masculino , Células de Sertoli/fisiologia , Hormônios Testiculares/sangue , Testosterona/sangue
11.
J Pediatr ; 129(6): 918-21, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8969738

RESUMO

Ovarian juvenile granulosa cell tumors are a rare cause of sexual precocity. Clinical examination, serum estradiol levels, and pelvic imaging studies have been used traditionally to detect such tumors. Immunoassays for müllerian inhibitory substance and inhibin have recently been noted to provide a more sensitive means of tumor detection in adults. We now describe two girls with this type of tumor in whom serum concentrations of inhibin and müllerian inhibitory substance were used as tumor markers.


Assuntos
Biomarcadores Tumorais/sangue , Glicoproteínas , Tumor de Células da Granulosa/diagnóstico , Inibidores do Crescimento/sangue , Substâncias de Crescimento/sangue , Inibinas/sangue , Ductos Paramesonéfricos , Neoplasias Ovarianas/diagnóstico , Hormônios Testiculares/sangue , Ativinas , Hormônio Antimülleriano , Criança , Pré-Escolar , Feminino , Humanos
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