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1.
Andrology ; 12(2): 289-296, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37377277

RESUMO

BACKGROUND: Cryptorchidism is one of the most common congenital disorders in boys and it is associated with a higher risk of sub-fertility and testicular cancer. Testicular descent occurs during embryo-fetal development in two phases, transabdominal and inguino-scrotal. In the latter process, androgens play a leading role. The androgen receptor has in its N-terminal domain, two aminoacidic repeats encoded by polymorphic nucleotide repetitions: (CAG)nCAA and GGN. The number of repetitions of these trinucleotides has been associated with different transactivation capacities and sensitivities of the androgen receptor response. OBJECTIVE: To determine whether pediatric Chilean individuals with idiopathic inguinal cryptorchidism have a different number of CAG and/or GGN repeats polymorphisms compared with controls. MATERIALS AND METHODS: A total of 109 cases with idiopathic inguinal cryptorchidism (26 bilateral and 83 unilateral) were studied by polymerase chain reaction amplification from DNA extracted from peripheral blood, followed by fragment size analysis by capillary electrophoresis, which were compared with 140 controls. RESULTS: The CAG26 repeats allele was increased in the total cases (8.3% vs. 1.4%; p = 0.012; odds ratio = 6.21, 95% confidence interval 1.31-29.4), and in bilateral cases compared to controls (11.5% vs. 1.4%; p = 0.028; odds ratio = 9 CI 95% 1.43-56.8). Similarly, CAG > 22 alleles were increased in the total cases (62.4% vs. 49.3%, p = 0.041), and more significantly in bilateral cases (73.1% vs. 49.3%; p = 0.032; odds ratio = 2.79, 95% confidence interval 1.1-7.1). In addition, CAG < 18 alleles were not observed among cases, but were present in 5.7% of controls (p = 0.01). Regarding the GGN repeats, no differences were observed between cases and controls either when analyzing separately unilateral and bilateral cryptorchidism. The joint analysis of the distribution of CAG and GGN alleles showed that the CAG26 allele was present with GGN23, hence the combination CAG26/GGN23 alleles was equally increased in bilateral cases compared with controls (11.5% vs. 1.4%). In contrast, CAG < 18 was preferably observed in the combination CAG < 18/GGN≠23 and was absent in the total cases (4.3% vs. 0%; p = 0.037). DISCUSSION: These results suggest that greater lengths of CAG alleles may contribute to a diminished androgen receptor function. The CAG26 allele alone or in combination with GGN23 was associated with a higher risk of bilateral cryptorchidism. On the other hand, CAG < 18 and the CAG < 18/GGN≠23 allele combination may reduce the probability of cryptorchidism.


Assuntos
Criptorquidismo , Neoplasias Testiculares , Criança , Humanos , Masculino , Chile , Criptorquidismo/genética , Receptores Androgênicos/genética , Neoplasias Testiculares/genética , Repetições de Trinucleotídeos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38012981

RESUMO

STUDY OBJECTIVE: To determine the metabolic effects of the subcutaneous etonogestrel implant compared with an oral contraceptive in adolescents and young adults (AYAs) with type 1 diabetes (T1D) on body weight, body composition, glucose, lipids, and C-reactive protein levels. METHODS: This was a non-randomized, interventional, prospective study. Thirty-nine AYAs with T1D participated; 20 used the implant (Implant-T1D), and 19 used an oral combined contraceptive (OC-T1D). Body composition, HbA1c, intermittent continuous glucose monitoring, lipids, and high-sensitivity C-reactive protein (hsCRP) levels were evaluated. RESULTS: All participants were followed for at least 12 months, and 26 completed the 24-month follow-up. No women discontinued the intervention due to adverse effects. Body weight increased by 0.8 ± 3.5 and 1 ± 2.9 kg in the OC-T1D and the Implant-T1D group at 12 months and by 2.6 ± 3.9 and 3.3 ± 3.6 kg at 24 months, respectively. OC-T1D and Implant-T1D had similar HbA1c, mean interstitial glucose levels, and time in range throughout the study; no significant difference over time was observed. hsCRP levels increased in both groups and were associated with BMI and HbA1c (P < .001 for both variables). Women in the OC-T1D group had higher total cholesterol, HDL-C, and triglyceride levels compared with the Implant-T1D. CONCLUSION: Glucose levels were similar in youth using the subdermal progestin implant and an OC. However, both AYA groups showed increased BMI, fat mass, and subclinical inflammation. Changes in lipid levels were associated with the OC method. These data highlight the importance of weight gain prevention in young women with T1D using hormonal contraception.

3.
J Clin Endocrinol Metab ; 107(3): e912-e923, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34752621

RESUMO

CONTEXT: First-degree relatives of women with polycystic ovary syndrome (PCOS) present hormonal and metabolic alterations compared to girls unrelated to PCOS. It is unknown whether glucose intolerance in the PCOS proband confers a more severe metabolic predisposition on their first-degree relatives. OBJECTIVE: To determine whether glucose tolerance status in women with PCOS is associated with worsened glucose metabolism and sex hormone levels in their peripubertal daughters or sisters. DESIGN: Cross-sectional study. SETTING: Seven academic centers in North America, South America, and Europe. PATIENTS: Sixty-four pairs of women with PCOS and their daughters or younger sisters aged between 8 and 14 years were recruited. Twenty-five mothers or older sisters with PCOS were glucose intolerant (GI) and 39 were normal glucose tolerant (NGT). MAIN OUTCOME MEASURES: Beta-cell function estimated by the insulin secretion-sensitivity index-2 (ISSI-2) during an oral glucose tolerance test and by the disposition index during a frequently sampled IV glucose tolerance test. Free testosterone and 17-hydroxyprogesterone (17-OHP) levels. RESULTS: Being related to a GI PCOS proband was associated with a lower ISSI-2 (P-value = 0.032) after adjusting for ethnicity, body mass index z-score, and pubertal stage. They also had higher free testosterone (P-value = 0.011) and 17-OHP levels compared to girls with an NGT proband, the latter becoming significant after adjusting for confounders (P-value = 0.040). CONCLUSIONS: Compared to first-degree female relatives of women with PCOS and NGT, first-degree relatives of women with PCOS and GI display lower beta-cell function and hyperandrogenemia, putting them at higher risk of GI and PCOS development.


Assuntos
Androgênios/sangue , Intolerância à Glucose/epidemiologia , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adolescente , Androgênios/metabolismo , Criança , Estudos Transversais , Feminino , Glucose/metabolismo , Intolerância à Glucose/sangue , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Núcleo Familiar , Ovário/patologia , Fatores de Risco , Irmãos
4.
Front Endocrinol (Lausanne) ; 12: 691240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149626

RESUMO

Noonan syndrome is characterized by multiple phenotypic features, including growth retardation, which represents the main cause of consultation to the clinician. Longitudinal growth during childhood and adolescence depends on several factors, among them an intact somatotrophic axis, which is characterized by an adequate growth hormone (GH) secretion by the pituitary, subsequent binding to its receptor, proper function of the post-receptor signaling pathway for this hormone (JAK-STAT5b and RAS/MAPK), and ultimately by the production of its main effector, insulin like growth factor 1 (IGF-1). Several studies regarding the function of the somatotrophic axis in patients with Noonan syndrome and data from murine models, suggest that partial GH insensitivity at a post-receptor level, as well as possible derangements in the RAS/MAPK pathway, are the most likely causes for the growth failure in these patients. Treatment with recombinant human growth hormone (rhGH) has been used extensively to promote linear growth in these patients. Numerous treatment protocols have been employed so far, but the published studies are quite heterogeneous regarding patient selection, length of treatment, and dose of rhGH utilized, so the true benefit of GH therapy is somewhat difficult to establish. This review will discuss the possible etiologies for the growth delay, as well as the outcomes following rhGH treatment in patients with Noonan syndrome.


Assuntos
Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Noonan/tratamento farmacológico , Animais , Modelos Animais de Doenças , Transtornos do Crescimento/etiologia , Humanos , Camundongos , Síndrome de Noonan/complicações , Resultado do Tratamento
5.
Growth Horm IGF Res ; 57-58: 101390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33975196

RESUMO

Testosterone and estrogen concentrations progressively increase during puberty, and in association with growth hormone (GH), lead to the increase in height velocity known as the pubertal growth spurt. Very limited information is available however, regarding the possible effects of sex steroids over GH cellular sensitivity. OBJECTIVE: To investigate the effects of different concentrations of testosterone, estradiol and dihydrotestosterone over the GH intracellular signaling pathway. METHODS: We evaluated the effects of these sex steroids on the nuclear phosphorylation of STAT5b and IGF-1 expression, in HEPG2 human hepatoma cells. In addition, we studied whether Tamoxifen (TAM), can modulate these effects. RESULTS: The highest concentration of T tested (10 ng/mL) co-incubated with a fixed concentration of GH (40 ng/mL) increased nuclear STAT5b phosphorylation compared with GH alone (1.34 ± 0.2 vs 0.6 ± 0.09 AU; *p < 0.05), as well as IGF-1 expression (0.6 ± 0.03 vs 0.32 ± 0.05 AU; *p < 0.05). This effect was not observed with lower concentrations of T tested (1 and 5 ng/mL). A similar increase in nuclear STAT5b phosphorylation was observed with the lowest concentration of E2 tested (20 pg/mL), co-incubated with the same fixed concentration of GH (3.6 ± 0.5 vs 1.28 ± 0.33 AU; *p < 0.05). This effect was also associated with an increase in IGF-1 expression (0.73 ± 0.02 vs 0.39 ± 0.04 AU; *p < 0.05). These results were not observed with higher concentrations of E2 tested (75 and 200 pg/mL). DHT at concentrations of 0.1, 0.25 and 0.5 ng/mL, co-stimulated with GH, did not change cytoplasmic STAT5b phosphorylation, nuclear STAT5b or IGF-1 expression. In addition, the co-incubation of TAM with the highest concentration of T tested (10 ng/mL) and GH (40 ng/mL) did not change cytoplasmic, nuclear pSTAT5 levels or IGF-1 expression. CONCLUSIONS: T and E2 potentiate the GH signaling pathway in a concentration-dependent fashion. The observation that the non-aromatizable androgen dihydrotestosterone does not stimulate this pathway, and that the effects of T are blocked with TAM, suggests that the effects of T over the GH signaling pathway appear to be mediated by estrogen.


Assuntos
Androgênios/farmacologia , Estrogênios/farmacologia , Hormônio do Crescimento Humano/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/efeitos dos fármacos , Fator de Transcrição STAT5/efeitos dos fármacos , Aromatase/metabolismo , Di-Hidrotestosterona/farmacologia , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Células Hep G2 , Hormônio do Crescimento Humano/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fosforilação/efeitos dos fármacos , Puberdade , Receptores de Estrogênio/metabolismo , Receptores da Somatotropina/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Tamoxifeno/farmacologia , Testosterona/farmacologia
6.
Am J Med Genet A ; 179(8): 1598-1602, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31145547

RESUMO

We report the case of a 14 years and 8 months girl, who is the first child of nonconsanguineous parents, with short stature, obstructive hypertrophic cardiomyopathy, multiple facial lentigines, high and wide forehead, downslanting palpebral fissures, low-set ears, short neck, and pectus excavatum; all features suggestive of Noonan syndrome with multiple lentigines (NSML). In addition, the patient exhibited craniosynostosis. Molecular analysis of rats sarcoma (RAS)/mitogen-activated protein kinase (MAPK) pathway genes with high-resolution melting curve analysis followed by sequencing showed a RAF1 amino acid substitution of valine to glycine at position 263 (p.V263G). The present report provides clinical data regarding the first association of a RAF1 variant and craniosynostosis in a patient with clinical diagnosis of NSML.


Assuntos
Craniossinostoses/diagnóstico , Craniossinostoses/genética , Variação Genética , Síndrome LEOPARD/diagnóstico , Síndrome LEOPARD/genética , Fenótipo , Proteínas Proto-Oncogênicas c-raf/genética , Adolescente , Alelos , Substituição de Aminoácidos , Éxons , Facies , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Mutação
7.
J Pediatr Adolesc Gynecol ; 32(2): 117-121, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30502496

RESUMO

STUDY OBJECTIVE: To compare ovarian function between adolescents conceived using assisted reproductive technology (AcART) and adolescents who were conceived spontaneously (AcSP). DESIGN: Multicenter study of ovarian function in AcART because of male or tubal infertility. SETTING: University Hospital. PARTICIPANTS: We evaluated 22 AcART and 53 AcSP at 1-2 years after menarche. The participants were born at term (≥37 weeks of gestation) with normal birth weights (≥2500 g) from singleton pregnancies. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Differences in ovulation, reproductive hormones, and ovarian morphology. RESULTS: AcART had an older age of menarche than that of AcSP, even after adjusting for maternal age at menarche, gestational age, and birth weight (P = .027). AcART had lower incidence of ovulation (P = .021) and higher luteinizing hormone serum levels (P = .01) than those of AcSP. The incidence of oligomenorrhea and the cycle length were similar between AcART and AcSP. AcART had levels of anti-Müllerian hormone, inhibin B, follicle-stimulating hormone, estradiol, and androgens similar to those of AcSP. The ovarian morphology, ovarian volume, and follicle counts were similar in both groups. CONCLUSION: AcART had later menarche, lower ovulation rates, and higher luteinizing hormone levels than those of AcSP. Future studies should investigate whether these findings are indicative of a risk of ovarian dysfunction later in life for AcART.


Assuntos
Ovário/fisiologia , Ovulação/fisiologia , Técnicas de Reprodução Assistida/efeitos adversos , Adolescente , Feminino , Hormônios Gonadais/sangue , Gonadotropinas/sangue , Humanos , Gravidez , Gravidez na Adolescência/fisiologia , Globulina de Ligação a Hormônio Sexual/análise , Ultrassonografia
8.
J Pediatr Genet ; 7(4): 158-163, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30430033

RESUMO

We report the case of a 3-year-old girl, who is the third child of nonconsanguineous parents, with short stature, hypertrophic cardiomyopathy, and mild dysmorphic features; all suggestive of Noonan syndrome. In addition, the patient presents with feeding difficulties, deep palmar and plantar creases, sparse hair, and delayed psychomotor and language development, all characteristics frequently observed in cardiofaciocutaneous syndrome. Molecular analysis of the Ras/ MAPK pathway genes using high-resolution melting curve analysis and gene sequencing revealed a de novo KRAS amino acid substitution of leucine to tryptophan at codon 53 (p.L53W). This substitution was recently described in an Iranian patient with Noonan syndrome. The findings described in this report expand the phenotypic heterogeneity observed in RASopathy patients harboring a KRAS substitution, and advocate for the inclusion of genes with low mutational frequency in genetic screening protocols for Noonan syndrome and other RASopathies.

9.
Pediatr Endocrinol Rev ; 16(Suppl 1): 100-104, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30378787

RESUMO

Noonan syndrome (NS) is a genetic disorder, which can present clinically with a variable phenotype. Proportional post natal short stature is a common manifestation of NS, with the majority of affected patients having an adult height below the third percentile. Some investigators have reported minor abnormalities in GH secretion and/or action, suggesting that recombinant growth hormone (rhGH) therapy may be useful for the treatment of their short stature. Our review of the literature regarding rhGH therapy in children with NS indicates that this therapy improves height velocity, but relatively few controlled clinical trials reporting adult height are available. rhGH treatment does not appear to be associated with adverse effects in these patients, but data on the possible development of malignancy during treatment are somewhat limited. Therefore, we believe that there is a need for large controlled clinical trials in patients with this condition, in order to accurately assess the effects of rhGH therapy over adult height.


Assuntos
Hormônio do Crescimento/uso terapêutico , Síndrome de Noonan , Estatura , Transtornos do Crescimento , Hormônio do Crescimento Humano , Humanos , Síndrome de Noonan/tratamento farmacológico
10.
Rev. chil. endocrinol. diabetes ; 11(3): 97-102, jul. 2018. ilus
Artigo em Espanhol | LILACS | ID: biblio-915180

RESUMO

Abstract: Sex hormones play a major role during pubertal growth. Estradiol (E2) and testosterone (T) levels progressively increase during puberty and in the presence of growth hormone (GH), growth velocity increases. Understanding the interactions between sex hormones and GH, may optimize the treatment of pubertal children with growth disorders. The aim of our study was to investigate possible molecular mechanisms which might potentiate longitudinal growth during puberty due to E 2or T combined with GH. We evaluated the GH/JAK2/STAT5 signaling pathway in the human hepatoma cell line HEPG2. Our results suggest that sex hormones potentiate the GH signaling pathway in a dose dependent fashion. Relatively low concentrations of E 2associated with GH induce a substantial activation of the GH pathway, whereas relatively high concentrations of T associated with GH produce a similar effect. These findings are concordant with the physiology of the pubertal growth spurt, which is an early event in girls (when E 2 circulating levels are low), and a late event in boys (when T circulating levels are high).


Resumen: Las hormonas sexuales, modulan el crecimiento durante la pubertad. Los niveles de estradiol (E2) y testosterona (T) aumentan progresivamente durante la pubertad y en combinación con la hormona de crecimiento (GH), producen un incremento en la velocidad de crecimiento en este período conocido como el "estirón puberal". El estudio de la interacción entre las hormonas sexuales y la GH, es de gran importancia para optimizar el tratamiento de niños(as) con alteraciones del crecimiento durante la pubertad. El objetivo de nuestro estudio fue investigar los posibles mecanismos que podrían potenciar el crecimiento longitudinal durante la pubertad, en especial las interacciones entre E 2o T en combinación con GH. Se evaluó la activación de la vía de señalización GH/JAK2/STAT5 frente al estímulo combinado con estas hormonas en cultivos celulares de hepatoma humana HEPG2. Nuestros resultados sugieren que existe un efecto potenciador de las hormonas sexuales sobre la vía de señalización de GH. Observamos que concentraciones relativamente bajas de E2 junto con GH producen una clara activación de la vía de señalización para GH, mientras que concentraciones relativamente altas de T junto con GH producen una activación similar. Estos hallazgos son concordantes con la fisiología del estirón puberal, que es más precoz en niñas (cuando los niveles circulantes de E2 son bajos), y más tardíos en varones (cuando los niveles circulantes de T son altos).


Assuntos
Humanos , Testosterona/fisiologia , Hormônio do Crescimento/fisiologia , Estradiol/fisiologia , Fator de Transcrição STAT5/fisiologia , Janus Quinase 2/fisiologia , Puberdade
11.
Artigo em Inglês | MEDLINE | ID: mdl-30697189

RESUMO

Introduction: Fetal growth restriction may be the consequence of maternal, fetal, or placental factors. The insulin-like growth factors (IGFs) are major determinants of fetal growth, and are expressed in the mother, fetus and placenta in most species. Previously we reported higher placental protein content of IGF-I, IGF-IR, and AKT in small (SGA) compared with those from appropriate for gestational age (AGA) placentas. The protein Klotho, has been reported in placenta and may regulate IGF-I activity. In this study we determined Klotho gene expression and protein immunostaining in term (T-SGA y T-AGA) and preterm (PT-SGA y PT-AGA) human placentas. In addition, we assessed the effect of Klotho on the IGF-IR and AKT activation induced by IGF-I. Methods: Placentas (n = 1 17) from 32 T-SGA (birth weight (BW) = -1.74 ± 0.08 SDS), 37 T-AGA (BW = 0.12 ± 0.12 SDS), 20 PT-SGA (BW = -2.08 ± 0.14 SDS), and 28 PT-AGA (BW = -0.43 ± 0.13 SDS) newborns were collected. mRNA expression by RT-PCR in the chorionic (CP) and basal (BP) plates of the placentas, and the presence of Klotho was evaluated by immunohistochemistry (integral optical density, IOD). In addition, we developed placental explants that were incubated with IGF-I in the presence or absence of Klotho. Results: We found a lower mRNA expression and protein immunoreactivity of Klotho in the CP of SGA (term and preterm) compared with AGA placentas. We also observed a significant reduction in IGF-IR tyrosine activation induced by IGF-I 10 nM when preincubated with 2.0 nM of Klotho (2.4 ± 0.5 arbitrary units vs. 1.3 ± 0.3 AU), and similar results we observed on AKT and ERK42/44 activation. Conclusion: We describe for the first time that Klotho mRNA and protein varies according to fetal growth and gestational age. In addition, Klotho appears to down-regulate the activation induced by IGF-I on IGF-IR and AKT, suggesting that Klotho may be regulating IGF-I activity in human placentas according to intrauterine fetal growth.

12.
J Pediatr Endocrinol Metab ; 30(5): 561-568, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28593921

RESUMO

BACKGROUND: During puberty there is a physiologic increase in adrenal and ovarian androgens. It has been suggested that the somatotrophic axis may be related to the development of hyperandrogenism and anovulation in non-obese adult women with polycystic ovarian syndrome (PCOS). The objective of the study was to investigate whether ovarian androgen secretion in young postmenarchal girls is related to the function of their somatotropic axis. METHODS: This was a cross-sectional study of adolescent girls. We studied non-obese adolescent girls with hyperandrogenism (HA; n = 21) matched with control girls (C; n = 25) for chronological age, age at menarche and body mass index. We obtained a fasting blood sample for measurement of serum glucose, insulin, 17-hydroxyprogesterone (17OH-Prog), dehydroepiandrosterone-sulfate (DHEA-S), androstenedione, sex hormone-binding globulin (SHBG), total testosterone, IGF-I, IGF-II, IGFBP-1, IGFBP-3, ghrelin, leptin, AMH (antiMüllerian hormone), luteinizing hormone (LH) and follicle stimulating hormone (FSH) during the follicular phase of the menstrual period. We performed an oral glucose tolerance test to determine blood glucose, insulin and ghrelin levels and urine samples to measure urinary GH (growth hormone) levels. RESULTS: As expected, the hyperandrogenic girls had significantly higher Ferriman scores, basal total testosterone, free androgen index (FAI), androstenedione, AMH, and basal LH levels compared with the girls in controls. Serum IGF-I, IGF-II, IGFBP-3 and urinary GH did not differ between HA and C. There was a correlation between urinary GH and FAI in all girls (r 0.29, p < 0.05). In addition, in HA girls FAI correlated with insulin, homeostasis model assessment (HOMA) and ghrelin. CONCLUSIONS: We observed a correlation between urinary GH and FAI in the hyperandrogenic and control girls, suggesting that the function of the somatotrophic axis may influence the secretion of androgens in adolescent girls.


Assuntos
Hormônios/metabolismo , Hiperandrogenismo/patologia , Ovário/fisiopatologia , Receptores da Somatotropina/metabolismo , Adolescente , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Hiperandrogenismo/metabolismo , Maturidade Sexual
13.
Horm Res Paediatr ; 87(6): 412-422, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28395282

RESUMO

BACKGROUND: The growth-promoting effects of IGF-I is mediated through the IGF-I receptor (IGF1R), a widely expressed cell-surface tyrosine kinase receptor. IGF1R copy number variants (CNV) can cause pre- and postnatal growth restriction or overgrowth. METHODS: Whole exome sequence (WES), chromosomal microarray, and targeted IGF1R gene analyses were performed on 3 unrelated children who share features of small for gestational age, short stature, and elevated serum IGF-I, but otherwise had clinical heterogeneity. Fluorescence-activated cell sorting (FACS) analysis of cell-surface IGF1R was performed on live primary cells derived from the patients. RESULTS: Two novel IGF1R CNV and a heterozygous IGF1R nonsense variant were identified in the 3 patients. One CNV (4.492 Mb) was successfully called from WES, utilizing eXome-Hidden Markov Model (XHMM) analysis. FACS analysis of cell-surface IGF1R on live primary cells derived from the patients demonstrated a ∼50% reduction in IGF1R availability associated with the haploinsufficiency state. CONCLUSION: In addition to conventional methods, IGF1R CNV can be identified from WES data. FACS analysis of live primary cells is a promising method for efficiently evaluating and screening for IGF1R haploinsufficiency. Further investigations are necessary to delineate how comparable IGF1R availability leads to the wide spectrum of clinical phenotypes and variable responsiveness to rhGH therapy.


Assuntos
Transtornos do Crescimento/genética , Haploinsuficiência , Receptores de Somatomedina/genética , Criança , Exoma , Feminino , Transtornos do Crescimento/diagnóstico , Humanos , Receptor IGF Tipo 1
14.
J Pediatr Endocrinol Metab ; 29(11): 1241-1248, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26887034

RESUMO

BACKGROUND: Triptorelin is an established treatment for central precocious puberty (CPP) as 1- and 3-month formulations. The current triptorelin 22.5 mg 6-month formulation is approved for prostate cancer therapy. This is the first study in patients with CPP. METHODS: The efficacy and safety of the triptorelin 6-month formulation in CPP were investigated. The primary objective was to evaluate the efficacy in achieving luteinizing hormone (LH) suppression to pre-pubertal levels at month 6. This was an international, non-comparative phase III study over 48 weeks. Eighteen medical centers in the US, Chile and Mexico participated. Forty-four treatment naïve patients (39 girls and five boys) aged at treatment start 2-8 years for girls and 2-9 years for boys with an advancement of bone age over chronological age ≥1 year were to be included. Triptorelin was administered im twice at an interval of 24 weeks. LH, follicle stimulating hormone (FSH) (basal and stimulated), estradiol (girls), testosterone (boys), auxological parameters, clinical signs of puberty and safety were assessed. RESULTS: Forty-one patients (93.2%) showed pre-pubertal LH levels (stimulated LH ≤5 IU/L) at month 6 and maintained LH suppression through month 12. The percentage of patients with LH suppression exceeded 93% at each time point and reached 97.7% at month 12. No unexpected drug-related adverse events were reported. CONCLUSIONS: The triptorelin 6-month formulation was safe and effective in suppressing the pituitary-gonadal axis in children with CPP. The extended injection interval may improve compliance and increase comfort in the management of CPP.


Assuntos
Hormônio Liberador de Gonadotropina/agonistas , Hormônio Luteinizante/antagonistas & inibidores , Puberdade Precoce/tratamento farmacológico , Substâncias para o Controle da Reprodução/administração & dosagem , Pamoato de Triptorrelina/administração & dosagem , Biomarcadores/sangue , Criança , Desenvolvimento Infantil/efeitos dos fármacos , Pré-Escolar , Chile , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Preparações de Ação Retardada/uso terapêutico , Esquema de Medicação , Estradiol/sangue , Estradiol/química , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante Humano/antagonistas & inibidores , Hormônio Foliculoestimulante Humano/sangue , Hormônio Foliculoestimulante Humano/metabolismo , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Masculino , México , Osteogênese/efeitos dos fármacos , Puberdade Precoce/sangue , Puberdade Precoce/metabolismo , Substâncias para o Controle da Reprodução/efeitos adversos , Substâncias para o Controle da Reprodução/uso terapêutico , Testosterona/antagonistas & inibidores , Testosterona/sangue , Testosterona/metabolismo , Pamoato de Triptorrelina/efeitos adversos , Pamoato de Triptorrelina/uso terapêutico , Estados Unidos
15.
Growth Horm IGF Res ; 27: 18-27, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26843474

RESUMO

BACKGROUND/AIM: Responsiveness to GH in target cells is mediated by its receptor, which activates the Janus kinase-2 (JAK2) and STAT5 (signal transducers and activators of transcription 5) leading to the expression of IGF-1 and IGFALS. The aim of this study was to compare the GH signaling pathway in newborns and prepubertal boys. SUBJECTS AND METHODS: We determined the GHR protein content and the effect of stimulation with recombinant human GH (rhGH; 200ng/mL) on JAK2 and STAT5 phosphorylation in skin fibroblast cultures obtained from newborns and prepubertal boys. The transcript levels of IGFALS and IGF-I, were also studied and compared after 16h or 24h of stimulation with GH in both study groups. RESULTS: Newborn infants showed less GHR protein than the prepubertal boys. After rhGH stimulation, JAK2 and STAT5 phosphorylation was absent in skin fibroblasts from newborns, but was clearly detectable in prepubertal boys. After 16h of treatment with rhGH, IGFALS and IGF-I transcript levels increased in the prepubertal boys when compared to baseline. In newborns, however, we did not observe a response after 16 and 24h of rhGH stimulation. CONCLUSION: The significant attenuation of the GH signaling pathway observed in fibroblasts from newborn boys appears to be related to a reduction in GHR content and lack of phosphorylation of JAK2 and STAT5 in response to rhGH. This might impair STAT5 dimer formation, leading to a reduction in the transcript levels of IGFALS and IGF-I during the newborn period.


Assuntos
Proteínas de Transporte/metabolismo , Fibroblastos/metabolismo , Glicoproteínas/metabolismo , Hormônio do Crescimento Humano/metabolismo , Janus Quinase 2/metabolismo , Puberdade/metabolismo , Receptores da Somatotropina/metabolismo , Fator de Transcrição STAT5/metabolismo , Pele/metabolismo , Western Blotting , Proteínas de Transporte/genética , Células Cultivadas , Criança , Fibroblastos/citologia , Glicoproteínas/genética , Hormônio do Crescimento Humano/genética , Humanos , Recém-Nascido , Janus Quinase 2/genética , Masculino , Fosforilação , Puberdade/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores da Somatotropina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT5/genética , Transdução de Sinais , Pele/citologia
16.
Gynecol Endocrinol ; 31(4): 260-3, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25392126

RESUMO

INTRODUCTION: Variations in inflammatory markers have been reported in adult women during the luteal phase, but whether these findings are observed during adolescence is unknown. We postulate that higher ultrasensitive C-reactive protein (usCRP) and lower 2-hydroxyestrone (2OHE) levels, an estrogen metabolite with cardioprotective actions, are present during the luteal phase in young women. AIM: To evaluate usCRP levels during the menstrual cycle and to determine its association with 2OHE and 16α-hydroxyestrone (16OHE) in adolescents. METHODS: Healthy postmenarcheal adolescents (N = 37) were studied during one menstrual cycle in follicular phase (FP) and luteal phase-like period (LP-L). RESULTS: Elevations in usCRP levels in the LP-L were observed in the entire group and in anovulatory cycles (1.9 ± 1.1 mg/L in FP to 2.5 ± 1.8 mg/L in LP-L; p < 0.0001). Increases in estrone, estradiol, free and bioavailable estradiol, testosterone, usCRP and 2OHE levels were observed in LP-L compared with FP (p < 0.01), with a borderline elevation in IFG-I levels (p = 0.06). CONCLUSIONS: We report an elevation of usCRP and 2OHE levels during the luteal phase in healthy adolescents. Elevations of this inflammatory marker in anovulatory adolescents without an increase in 2OHE may play a role in metabolic risks associated with chronic anovulation.


Assuntos
Desenvolvimento do Adolescente , Proteína C-Reativa/análise , Fase Luteal/sangue , Regulação para Cima , Adolescente , Biomarcadores/sangue , Biomarcadores/urina , Chile , Feminino , Fase Folicular/sangue , Fase Folicular/urina , Humanos , Hidroxiestronas/urina , Fase Luteal/urina , Progesterona/sangue , Valores de Referência , Saúde da População Urbana
17.
PLoS One ; 9(7): e102252, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25050889

RESUMO

INTRODUCTION: The human placenta expresses the IGF-I and IGF-IR proteins and their intracellular signal components (IRS-1, AKT and mTOR). The aim of this study was to assess the IGF-IR content and activation of downstream signaling molecules in placentas from newborns who were classified by gestational age and birth weight. We studied placentas from 25 term appropriate (T-AGA), 26 term small (T-SGA), 22 preterm AGA (PT-AGA), and 20 preterm SGA (PT-SGA) newborns. The total and phosphorylated IGF-IR, IRS-1, AKT, and mTOR contents were determined by Western Blot and normalized by actin or with their respective total content. The effect of IGF-I was determined by stimulating placental explants with recombinant IGF-I 10-8 mol/L for 15, 30, and 60 minutes. RESULTS: The IGF-IR content was higher in T-SGA compared to T-AGA placentas, and the IRS-1 content was higher in PT-placentas compared with their respective T-placentas. The effect of IGF-I on the phosphorylated forms of IGF-IR was increased in T-SGA (150%) and PT-SGA (300%) compared with their respective AGA placentas. In addition, AKT serine phosphorylation was higher in PT-SGA compared to PT-AGA and T-SGA placentas (90% and 390% respectively). CONCLUSION: The higher protein content and response to IGF-I of IGF-IR, IRS-1, and AKT observed in SGA placentas may represent a compensatory mechanism in response to fetal growth restriction.


Assuntos
Peso ao Nascer , Idade Gestacional , Fator de Crescimento Insulin-Like I/fisiologia , Placenta/metabolismo , Receptor IGF Tipo 1/metabolismo , Feminino , Retardo do Crescimento Fetal/metabolismo , Humanos , Recém-Nascido de Baixo Peso/metabolismo , Recém-Nascido , Masculino , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Técnicas de Cultura de Tecidos
18.
Growth Horm IGF Res ; 24(4): 119-22, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24857397

RESUMO

BACKGROUND: The possible relationship between the circulating concentrations of T4 and GH sensitivity has not been elucidated. OBJECTIVE: The aim of this study is to evaluate the effect of levothyroxine supplementation on GH sensitivity in prepubertal boys with idiopathic short stature (ISS). METHODS: We selected 28 prepubertal boys with ISS (mean age 8.2±0.5years) and free T4 (Ft4) concentrations between the 3rd and the 25th percentiles (Ft4: 0.8-1.5ng/dl). They were randomly divided into two groups: Group A received thyroid supplementation (1-3µg/kg/day) for 120days, and Group B received placebo for the same period. To evaluate GH sensitivity, an IGF-I generation test (GH: 33µg/kg/day sc for 3days) was performed in both groups: under basal conditions, and after 120days of levothyroxine supplementation (or placebo). RESULTS: After thyroid supplementation, Group A had higher Ft4 concentrations compared with Group B (2.14±0.06 vs 1.48±0.06ng/dl, p=0.01), their growth velocity was significantly higher (2.3±0.1 vs 1.5±0.2cm/4months), and they exhibited a greater increase in IGF-I after GH administration (Group A: 32.5±3.8% vs Group B 17.3±2.6%). CONCLUSION: Supplementation with levothyroxine for 120days promotes an increase in growth velocity, and a greater IGF-I response to short-term GH administration in prepubertal boys with ISS and low-normal thyroid hormone concentrations.


Assuntos
Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento/uso terapêutico , Tiroxina/uso terapêutico , Estatura/efeitos dos fármacos , Criança , Humanos , Fator de Crescimento Insulin-Like I/análise , Masculino , Tiroxina/sangue , Tiroxina/farmacologia , Resultado do Tratamento
19.
Int J Pediatr Endocrinol ; 2014(1): 6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24745883

RESUMO

BACKGROUND: Prepubertal hypertrichosis is a reportedly benign condition characterized by an excessive growth of vellous hair in non-androgen dependent areas of the body compared to the amount usually present in normal subjects of the same age, race and sex. Although this condition is usually considered idiopathic and regarded as benign, it may be very disturbing cosmetically, causing significant patient and parental anxiety. METHOD: We performed a hormonal and androgen receptor study in 42 prepubertal girls with hypertrichosis and 29 control girls from 2 to 8 years of age. Both groups underwent a determination of basal LH, FSH, 17OH progesterone, androstenedione, testosterone, estradiol and SHBG, abdominal ultrasound to assess ovarian morphology, and the number of androgen receptor CAG/GGC repeats in DNA obtained from peripheral leukocytes. RESULTS: The hypertrichosis score was higher in the cases compared to controls. Serum gonadotropins and sex steroids were similar in both groups, but SHBG was significantly lower in the girls with hypertrichosis (71.1 ± 2.9 vs 81.9 ± 3.0 nmol/L, p < 0.02). The distribution of shorter, larger and total alleles was not statistically different between cases and controls. The combined analysis of CAG/GGC, however, showed a significantly higher prevalence of the most androgen-sensitive haplotypes (1-2: <22CAG + 17/17GGC- < 14CAG + 17/18GGC) in girls with hypertrichosis compared to controls. CONCLUSIONS: We conclude that girls with hypertrychosis exhibit AR(s) with enhanced sensitivity, which may facilitate the growth of their body hair.

20.
Am J Med Genet A ; 164A(5): 1204-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24664892

RESUMO

Laron syndrome (LS) is a genetic disorder caused by mutations in the growth hormone receptor (GHR) gene. The most frequent GHR mutation is E180splice (rs121909360), which was initially found in an inbred population of Spanish descent in Ecuador and subsequently in Israel, Brazil, Chile, and the United States. The aim of the present study is to determine if the E180splice mutation arose from a common origin. We studied 22 patients with LS from Ecuador, Israel (of Moroccan origin), Brazil, Chile, and the United States (of Mexican origin) who were homozygous for the E180splice mutation and compared them to control individuals for markers surrounding the GHR, intragenic polymorphisms, and Y-chromosome STR. An identical haplotype was found in all but one of the subjects carrying the E180splice mutation: D5S665: 150/150; D5S2082: 192/192; D5S2087: 246/246; rs6179 G/G; and rs6180 C/C. One patient differed from the others only at D5S2082 (168/192). This haplotype is rare (~1%) in control individuals and confirmed that the E180splice-associated haplotype was not derived from independent origins but represented recombination from a common ancestor. The analysis of paternal lineage markers showed that 50% belong to haplogroup R1b (found in Portugal and Spain) and 40% to haplogroups J and E (typical in the Middle East and in Eastern European Jews). The germline E180Splice mutation appears to have originated from a single common ancestor. The presence of Y-chromosome markers associated with Sephardic populations in persons harboring the E180splice mutation provides genetic evidence in support of the historical tracking of the exodus of this specific population.


Assuntos
Síndrome de Laron/diagnóstico , Síndrome de Laron/genética , Mutação , Sítios de Splice de RNA , Receptores da Somatotropina/genética , Brasil , Cromossomos Humanos Y , DNA Mitocondrial , Equador , Feminino , Haplótipos , Homozigoto , Humanos , Israel , Judeus/genética , Masculino , Repetições de Microssatélites
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