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1.
Nat Commun ; 14(1): 8097, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062045

RESUMO

Innervation of the hypothalamic median eminence by Gonadotropin-Releasing Hormone (GnRH) neurons is vital to ensure puberty onset and successful reproduction. However, the molecular and cellular mechanisms underlying median eminence development and pubertal timing are incompletely understood. Here we show that Semaphorin-6A is strongly expressed by median eminence-resident oligodendrocytes positioned adjacent to GnRH neuron projections and fenestrated capillaries, and that Semaphorin-6A is required for GnRH neuron innervation and puberty onset. In vitro and in vivo experiments reveal an unexpected function for Semaphorin-6A, via its receptor Plexin-A2, in the control of median eminence vascular permeability to maintain neuroendocrine homeostasis. To support the significance of these findings in humans, we identify patients with delayed puberty carrying a novel pathogenic variant of SEMA6A. In all, our data reveal a role for Semaphorin-6A in regulating GnRH neuron patterning by tuning the median eminence vascular barrier and thereby controlling puberty onset.


Assuntos
Hormônio Liberador de Gonadotropina , Semaforinas , Humanos , Hormônio Liberador de Gonadotropina/metabolismo , Eminência Mediana/metabolismo , Permeabilidade Capilar , Neurônios/metabolismo , Puberdade , Semaforinas/genética , Semaforinas/metabolismo
2.
Lancet Diabetes Endocrinol ; 11(3): 203-216, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36620967

RESUMO

Puberty is a major maturational event; its mechanisms and timing are driven by genetic determinants, but also controlled by endogenous and environmental cues. Substantial progress towards elucidation of the neuroendocrine networks governing puberty has taken place. However, key aspects of the mechanisms responsible for the precise timing of puberty and its alterations have only recently begun to be deciphered, propelled by epidemiological data suggesting that pubertal timing is changing in humans, via mechanisms that are not yet understood. By integrating basic and clinical data, we provide a comprehensive overview of current advances on the physiological basis of puberty, with a particular focus on the roles of kisspeptins and other central transmitters, the underlying molecular and endocrine mechanisms, and the pathways involved in pubertal modulation by nutritional and metabolic cues. Additionally, we have summarised molecular features of precocious and delayed puberty in both sexes, as revealed by clinical and genetic studies. This Review is a synoptic up-to-date view of how puberty is controlled and of the pathogenesis of major pubertal alterations, from both a clinical and translational perspective. We also highlight unsolved challenges that will seemingly concentrate future research efforts in this active domain of endocrinology.


Assuntos
Puberdade Precoce , Puberdade , Masculino , Feminino , Humanos , Kisspeptinas/genética , Kisspeptinas/metabolismo , Puberdade Precoce/genética
3.
Hypertension ; 77(3): 1010-1019, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33517680

RESUMO

The purpose of this prospective, population-based cohort study was to evaluate the roles of polycystic ovary syndrome (PCOS), obesity, weight gain, and hyperandrogenemia in the development of hypertensive disorders of pregnancy (HDP) through fertile age both in PCOS and in non-PCOS women. The study population-NFBC1966 (Northern Finland Birth Cohort 1966)-allowed a long-term follow-up of women from age 14 until 46 years who developed HDP (n=408) or did not (n=3373). HDP diagnosis was confirmed by combining hospital discharge records, data from Finnish Medical Birth Registers, and the questionnaire data at age 46. Women with self-reported PCOS (srPCOS; n=279), defined by both oligo-amenorrhea and hirsutism at age 31 or with PCOS diagnosis by age 46, were compared with women without reported PCOS (n=1577). Women with srPCOS had an increased HDP risk (odds ratio, 1.56 [95% CI, 1.03-2.37]), but the association disappeared after adjustment for body mass index. In women with srPCOS and HDP, body mass index increased from age 14 to 46 significantly more than in srPCOS women without HDP (median [interquartile range], 9.82 [6.23-14.6] and 7.21 [4.16-10.5] kg/m2, respectively; P<0.001). Also, in non-PCOS women, the increase was higher in women with (7.54 [5.32-11.62] kg/m2; P<0.001) than without HDP (6.33 [3.90-9.33] kg/m2; P<0.001). Increase in waist circumference between ages 31 and 46 years was associated with HDP but not with PCOS. Hyperandrogenemia at 31 or 46 years did not associate with HDP (1.44 [0.98-2.11]). In conclusion, obesity, especially abdominal obesity, and weight gain from adolescence to age 46, but not srPCOS or hyperandrogenemia, were associated with an increased risk of HDP.


Assuntos
Hiperandrogenismo/fisiopatologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Obesidade/fisiopatologia , Síndrome do Ovário Policístico/fisiopatologia , Aumento de Peso/fisiologia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico , Modelos Logísticos , Pessoa de Meia-Idade , Vigilância da População , Gravidez , Estudos Prospectivos , Fatores de Risco , Autorrelato , Adulto Jovem
4.
Acta Paediatr ; 110(3): 881-888, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32794225

RESUMO

AIM: The aim was to compare the performances of the World Health Organization (WHO) and population-based (PB) references in the screening for hydrocephalus in infants aged <2 years. METHODS: We collected 341 longitudinal head circumference (HC) measurements of hydrocephalic infants and 120 181 measurements of 15 145 healthy infants from primary care. The measurements were converted into z-scores, and a new screening parameter, change in HC standard deviation score (SDS) over time (ΔHC SDS), was calculated. Comparisons were made using receiver operating characteristics analysis and linear mixed models. RESULTS: The mean HC SDSWHO was 3.5 and the mean HC SDSPB was 2.9 in the hydrocephalic infants, and in healthy children, those numbers were 1.0 SDSWHO and 0 SDSPB , respectively. The best screening accuracy was obtained with the PB reference in combination with the ΔHC SDS parameter (AUC 0.89). The accuracy of the WHO standard could be improved to a similar level by customising the screening cut-offs of HC SDS according to the population and combining screening parameters. CONCLUSIONS: Auxology alone was not sufficient for the screening of hydrocephalus. The WHO standard should be validated in the population, and population-specific cut-offs for normality defined before its introduction.


Assuntos
Hidrocefalia , Idoso , Cefalometria , Criança , Cabeça/anatomia & histologia , Humanos , Hidrocefalia/diagnóstico , Lactente , Programas de Rastreamento , Organização Mundial da Saúde
5.
JCI Insight ; 5(11)2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32493844

RESUMO

The initiation of puberty is driven by an upsurge in hypothalamic gonadotropin-releasing hormone (GnRH) secretion. In turn, GnRH secretion upsurge depends on the development of a complex GnRH neuroendocrine network during embryonic life. Although delayed puberty (DP) affects up to 2% of the population, is highly heritable, and is associated with adverse health outcomes, the genes underlying DP remain largely unknown. We aimed to discover regulators by whole-exome sequencing of 160 individuals of 67 multigenerational families in our large, accurately phenotyped DP cohort. LGR4 was the only gene remaining after analysis that was significantly enriched for potentially pathogenic, rare variants in 6 probands. Expression analysis identified specific Lgr4 expression at the site of GnRH neuron development. LGR4 mutant proteins showed impaired Wnt/ß-catenin signaling, owing to defective protein expression, trafficking, and degradation. Mice deficient in Lgr4 had significantly delayed onset of puberty and fewer GnRH neurons compared with WT, whereas lgr4 knockdown in zebrafish embryos prevented formation and migration of GnRH neurons. Further, genetic lineage tracing showed strong Lgr4-mediated Wnt/ß-catenin signaling pathway activation during GnRH neuron development. In conclusion, our results show that LGR4 deficiency impairs Wnt/ß-catenin signaling with observed defects in GnRH neuron development, resulting in a DP phenotype.


Assuntos
Neurônios , Puberdade Tardia , Receptores Acoplados a Proteínas G/deficiência , Via de Sinalização Wnt , Animais , Feminino , Seguimentos , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Masculino , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Puberdade Tardia/genética , Puberdade Tardia/metabolismo , Puberdade Tardia/patologia , Receptores Acoplados a Proteínas G/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-31396156

RESUMO

Cryptorchidism, or undescended testis, is a well-known risk factor for testicular cancer and impaired semen quality in adulthood, conditions which have their origins in early fetal and postnatal life. In human pregnancy, the interplay of testicular and placental hormones as well as local regulatory factors and control by the hypothalamic-pituitary (HP) axis, lead to testicular descent by term. The normal masculine development may be disrupted by environmental factors or genetic defects and result in undescended testes. Minipuberty refers to the postnatal re-activation of the HP-testicular (T) axis after birth. During the first weeks of life, gonadotropin levels increase, followed by activation and proliferation of testicular Leydig, Sertoli and germ cells. Consequent rise in testosterone levels results in penile growth during the first months of life. Testicular size increases and testicular descent continues until three to five months of age. Insufficient HPT axis activation (e.g., hypogonadotropic hypogonadism) is often associated with undescended testis and therefore minipuberty is considered an important phase in the normal male reproductive development. Minipuberty provides a unique window of opportunity for the early evaluation of HPT axis function during early infancy. For cryptorchid boys, hormonal evaluation during minipuberty may give a hint of the underlying etiology and aid in the evaluation of the later risk of HPT axis dysfunction and impaired fertility. The aim of this review is to summarize the current knowledge of the role of minipuberty in testicular development and descent.

7.
Endocr Rev ; 40(5): 1285-1317, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220230

RESUMO

This review presents a comprehensive discussion of the clinical condition of delayed puberty, a common presentation to the pediatric endocrinologist, which may present both diagnostic and prognostic challenges. Our understanding of the genetic control of pubertal timing has advanced thanks to active investigation in this field over the last two decades, but it remains in large part a fascinating and mysterious conundrum. The phenotype of delayed puberty is associated with adult health risks and common etiologies, and there is evidence for polygenic control of pubertal timing in the general population, sex-specificity, and epigenetic modulation. Moreover, much has been learned from comprehension of monogenic and digenic etiologies of pubertal delay and associated disorders and, in recent years, knowledge of oligogenic inheritance in conditions of GnRH deficiency. Recently there have been several novel discoveries in the field of self-limited delayed puberty, encompassing exciting developments linking this condition to both GnRH neuronal biology and metabolism and body mass. These data together highlight the fascinating heterogeneity of disorders underlying this phenotype and point to areas of future research where impactful developments can be made.


Assuntos
Puberdade Tardia/genética , Animais , Epigênese Genética , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Liberador de Gonadotropina/fisiologia , Humanos , Masculino , Fenótipo , Puberdade Tardia/diagnóstico , Puberdade Tardia/etiologia , Puberdade Tardia/fisiopatologia , Caracteres Sexuais
8.
Hum Mol Genet ; 28(8): 1357-1368, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30608578

RESUMO

The initiation of puberty is orchestrated by an augmentation of gonadotropin-releasing hormone (GnRH) secretion from a few thousand hypothalamic neurons. Recent findings have indicated that the neuroendocrine control of puberty may be regulated by a hierarchically organized network of transcriptional factors acting upstream of GnRH. These include enhanced at puberty 1 (EAP1), which contributes to the initiation of female puberty through transactivation of the GnRH promoter. However, no EAP1 mutations have been found in humans with disorders of pubertal timing. We performed whole-exome sequencing in 67 probands and 93 relatives from a large cohort of familial self-limited delayed puberty (DP). Variants were analyzed for rare, potentially pathogenic variants enriched in case versus controls and relevant to the biological control of puberty. We identified one in-frame deletion (Ala221del) and one rare missense variant (Asn770His) in EAP1 in two unrelated families; these variants were highly conserved and potentially pathogenic. Expression studies revealed Eap1 mRNA abundance in peri-pubertal mouse hypothalamus. EAP1 binding to the GnRH1 promoter increased in monkey hypothalamus at the onset of puberty as determined by chromatin immunoprecipitation. Using a luciferase reporter assay, EAP1 mutants showed a reduced ability to trans-activate the GnRH promoter compared to wild-type EAP1, due to reduced protein levels caused by the Ala221del mutation and subcellular mislocation caused by the Asn770His mutation, as revealed by western blot and immunofluorescence, respectively. In conclusion, we have identified the first EAP1 mutations leading to reduced GnRH transcriptional activity resulting in a phenotype of self-limited DP.


Assuntos
Hormônio Liberador de Gonadotropina/fisiologia , Puberdade Tardia/genética , Securina/genética , Adolescente , Adulto , Animais , Criança , Feminino , Regulação da Expressão Gênica/genética , Hormônio Liberador de Gonadotropina/genética , Humanos , Hipotálamo/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , Regiões Promotoras Genéticas/genética , Puberdade/genética , Puberdade/fisiologia , RNA Mensageiro/genética , Securina/fisiologia , Maturidade Sexual/genética , Transativadores/genética , Fatores de Transcrição/genética , Sequenciamento do Exoma , Adulto Jovem
9.
J Clin Endocrinol Metab ; 103(9): 3420-3429, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29931354

RESUMO

Context: Self-limited delayed puberty (DP) segregates in an autosomal-dominant pattern, but the genetic basis is largely unknown. Although DP is sometimes seen in relatives of patients with hypogonadotropic hypogonadism (HH), mutations in genes known to cause HH that segregate with the trait of familial self-limited DP have not yet been identified. Objective: To assess the contribution of mutations in genes known to cause HH to the phenotype of self-limited DP. Design, Patients, and Setting: We performed whole-exome sequencing in 67 probands and 93 relatives from a large cohort of familial self-limited DP, validated the pathogenicity of the identified gene variant in vitro, and examined the tissue expression and functional requirement of the mouse homolog in vivo. Results: A potentially pathogenic gene variant segregating with DP was identified in 1 of 28 known HH genes examined. This pathogenic variant occurred in HS6ST1 in one pedigree and segregated with the trait in the six affected members with heterozygous transmission (P = 3.01 × 10-5). Biochemical analysis showed that this mutation reduced sulfotransferase activity in vitro. Hs6st1 mRNA was expressed in peripubertal wild-type mouse hypothalamus. GnRH neuron counts were similar in Hs6st1+/- and Hs6st1+/+ mice, but vaginal opening was delayed in Hs6st1+/- mice despite normal postnatal growth. Conclusions: We have linked a deleterious mutation in HS6ST1 to familial self-limited DP and show that heterozygous Hs6st1 loss causes DP in mice. In this study, the observed overlap in potentially pathogenic mutations contributing to the phenotypes of self-limited DP and HH was limited to this one gene.


Assuntos
Hipogonadismo/genética , Puberdade Tardia/genética , Sulfotransferases/deficiência , Animais , Estudos de Coortes , Feminino , Finlândia , Hormônio Liberador de Gonadotropina/genética , Heterozigoto , Humanos , Hipotálamo/metabolismo , Masculino , Camundongos , Mutação , Linhagem , Fenótipo , Sulfotransferases/genética , Sequenciamento do Exoma
10.
Clin Endocrinol (Oxf) ; 89(1): 85-92, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29668033

RESUMO

BACKGROUND: The postnatal gonadotrophin surge is sexually dimorphic: FSH levels predominate in girls and LH levels in boys. However, in preterm (PT) girls, both gonadotrophin levels are higher than in PT boys. OBJECTIVE: To evaluate how gonadal maturation contributes to the sex differences in FSH and LH. DESIGN: Monthly follow-up of 58 full-term (FT, 29 boys) and 67 PT (33 boys) infants from 1 week (D7) to 6 months of age (M1-M6). Analyses were also carried out according to postmenstrual (PM) age in PT infants. METHODS: Urinary LH, FSH, oestradiol (E2), testosterone (T) and serum inhibin B (InhB) levels. RESULTS: High gonadotrophin levels in PT girls abruptly decreased (P < .001) by M2, corresponding to a PM age of 38-42 weeks, and LH levels fell below the levels found in boys. This decrease was parallel to a steep increase in E2 levels (P < .001), and, from M4 to M6, LH and E2 correlated positively in PT girls (P < .01). T levels in PT boys increased earlier than E2 levels in PT girls. In addition, InhB levels were high in PT boys already at D7, in contrast to low InhB in PT girls. InhB and FSH correlated negatively in the whole group (P < .001). CONCLUSIONS: Ovarian hormone synthesis is immature and incapable of responding to gonadotrophin stimulus before 38-42 PM weeks in PT girls, which may explain their highly elevated FSH and LH levels. The higher InhB levels in boys compared to girls may explain sexual dimorphism in FSH levels.


Assuntos
Gonadotropinas/urina , Hormônio Luteinizante/metabolismo , Ovário/metabolismo , Hormônios Testiculares/metabolismo , Testículo/metabolismo , Estradiol/urina , Feminino , Hormônio Foliculoestimulante/urina , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/metabolismo , Recém-Nascido Prematuro/urina , Inibinas/urina , Hormônio Luteinizante/urina , Masculino , Ovário/patologia , Hormônios Testiculares/urina , Testículo/patologia
11.
J Clin Endocrinol Metab ; 102(9): 3349-3359, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911133

RESUMO

Context: The human fetal adrenal (HFA) is an integral component of the fetoplacental unit and important for the maintenance of pregnancy. Low kisspeptin levels during pregnancy are associated with miscarriage, and kisspeptin and its receptor are expressed in the HFA. However, the role of kisspeptin in fetal adrenal function remains unknown. Objective: To determine the role of kisspeptin in the developing HFA. Design: Experiments using H295R and primary HFA cells as in vitro models of the fetal adrenal. Association of plasma kisspeptin levels with HFA size in a longitudinal clinical study. Setting: Academic research center and tertiary fetal medicine unit. Participants: Thirty-three healthy pregnant women were recruited at their 12-week routine antenatal ultrasound scan. Main Outcome Measures: The spatiotemporal expression of Kiss1R in the HFA. The production of dehydroepiandrosterone sulfate (DHEAS) from HFA cells after kisspeptin treatment, alone or in combination with adrenocorticotropic hormone or corticotropin-releasing hormone. Fetal adrenal volume (FAV) and kisspeptin levels at four antenatal visits (∼20, 28, 34, and 38 weeks' gestation). Results: Expression of Kiss1R was present in the HFA from 8 weeks after conception to term and was shown in the inner fetal zone. Kisspeptin significantly increased DHEAS production in H295R and second-trimester HFA cells. Serial measurements of kisspeptin confirmed a correlation with FAV growth in the second trimester, independent of sex or estimated fetal weight. Conclusions: Kisspeptin plays a key role in the regulation of the HFA and thus the fetoplacental unit, particularly in the second trimester of pregnancy.


Assuntos
Córtex Suprarrenal/embriologia , Glândulas Suprarrenais/embriologia , Desenvolvimento Fetal/fisiologia , Kisspeptinas/sangue , Córtex Suprarrenal/crescimento & desenvolvimento , Glândulas Suprarrenais/crescimento & desenvolvimento , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Análise de Variância , Biomarcadores/sangue , Hormônio Liberador da Corticotropina/metabolismo , Feminino , Humanos , Gravidez , Resultado da Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal , Adulto Jovem
12.
Mol Cell Endocrinol ; 447: 12-22, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28232089

RESUMO

GnRH neurons are fundamental for reproduction in all vertebrates, integrating all reproductive inputs. The inaccessibility of human GnRH-neurons has been a major impediment to studying the central control of reproduction and its disorders. Here, we report the efficient generation of kisspeptin responsive GnRH-secreting neurons by directed differentiation of human Embryonic Stem Cells and induced-Pluripotent Stem Cells derived from a Kallman Syndrome patient and a healthy family member. The protocol involves the generation of intermediate Neural Progenitor Cells (NPCs) through long-term Bone morphogenetic protein 4 inhibition, followed by terminal specification of these NPCs in media containing Fibroblast Growth Factor 8 and a NOTCH inhibitor. The resulting GnRH-expressing and -secreting neurons display a neuroendocrine gene expression pattern and present spontaneous calcium transients that can be stimulated by kisspeptin. These in vitro generated GnRH expressing cells provide a new resource for studying the molecular mechanisms underlying the development and function of GnRH neurons.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Kisspeptinas/metabolismo , Neurônios/metabolismo , Células-Tronco Pluripotentes/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Linhagem Celular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Células-Tronco Neurais/metabolismo
13.
Cell Rep ; 16(4): 1026-1038, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27396331

RESUMO

A surface marker that distinctly identifies cardiac progenitors (CPs) is essential for the robust isolation of these cells, circumventing the necessity of genetic modification. Here, we demonstrate that a Glycosylphosphatidylinositol-anchor containing neurotrophic factor receptor, Glial cell line-derived neurotrophic factor receptor alpha 2 (Gfra2), specifically marks CPs. GFRA2 expression facilitates the isolation of CPs by fluorescence activated cell sorting from differentiating mouse and human pluripotent stem cells. Gfra2 mutants reveal an important role for GFRA2 in cardiomyocyte differentiation and development both in vitro and in vivo. Mechanistically, the cardiac GFRA2 signaling pathway is distinct from the canonical pathway dependent on the RET tyrosine kinase and its established ligands. Collectively, our findings establish a platform for investigating the biology of CPs as a foundation for future development of CP transplantation for treating heart failure.


Assuntos
Diferenciação Celular/fisiologia , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Transdução de Sinais/fisiologia , Animais , Células Cultivadas , Glicosilfosfatidilinositóis/metabolismo , Humanos , Ligantes , Camundongos , Organogênese/fisiologia , Células-Tronco Pluripotentes/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo
14.
Pediatrics ; 138(1)2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27283013

RESUMO

BACKGROUND AND OBJECTIVE: Transient activation of the hypothalamic-pituitary-gonadal axis with a sex steroid surge is observed in boys and girls during the first months of life. However, the role of sex steroids in the regulation of growth has not been substantiated in infancy. We tested the hypothesis that testosterone (T) surge, known to be higher in infant boys than in girls during the transient postnatal gonadal activation regulates linear growth in infants. METHODS: To characterize in detail the linear growth velocity (GV) differences between genders in the normal population in early infancy, we evaluated growth of 18 570 healthy infants (51.0% boys) with 162 003 height measurements from birth to 12 months of age. GV was monitored and compared with serially measured urinary T and estradiol levels and serum insulin-like growth factor 1 levels in 84 healthy infants (45% boys) during the first 6 months of life. RESULTS: GV was significantly faster from birth to 6 months of age in boys than in girls (P ≤ .01). The greatest GV difference, 4.1 cm per year, was observed at 1 month of age, simultaneously with the peak of postnatal gonadal activation. In the mixed model analysis, GV showed a significant positive association with T in both genders (parameter estimate up to 0.62, 95% confidence interval 0.44-0.81). CONCLUSIONS: These results provide a new insight into the regulation of growth in infants and elucidate a novel biological role of the transient postnatal gonadal activation in growth regulation.


Assuntos
Estatura/fisiologia , Desenvolvimento Infantil/fisiologia , Estradiol/urina , Crescimento/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , Testosterona/urina , Biomarcadores/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Modelos Estatísticos , Estudos Prospectivos , Caracteres Sexuais
15.
EMBO Mol Med ; 8(6): 626-42, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27137492

RESUMO

Early or late pubertal onset affects up to 5% of adolescents and is associated with adverse health and psychosocial outcomes. Self-limited delayed puberty (DP) segregates predominantly in an autosomal dominant pattern, but the underlying genetic background is unknown. Using exome and candidate gene sequencing, we have identified rare mutations in IGSF10 in 6 unrelated families, which resulted in intracellular retention with failure in the secretion of mutant proteins. IGSF10 mRNA was strongly expressed in embryonic nasal mesenchyme, during gonadotropin-releasing hormone (GnRH) neuronal migration to the hypothalamus. IGSF10 knockdown caused a reduced migration of immature GnRH neurons in vitro, and perturbed migration and extension of GnRH neurons in a gnrh3:EGFP zebrafish model. Additionally, loss-of-function mutations in IGSF10 were identified in hypothalamic amenorrhea patients. Our evidence strongly suggests that mutations in IGSF10 cause DP in humans, and points to a common genetic basis for conditions of functional hypogonadotropic hypogonadism (HH). While dysregulation of GnRH neuronal migration is known to cause permanent HH, this is the first time that this has been demonstrated as a causal mechanism in DP‡.


Assuntos
Movimento Celular , Imunoglobulinas/genética , Proteínas Mutantes/genética , Neurônios/fisiologia , Puberdade Tardia/fisiopatologia , Adolescente , Animais , Análise Mutacional de DNA , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Hipotálamo/citologia , Masculino , Modelos Animais , Neurônios/metabolismo , Análise de Sequência de DNA , Peixe-Zebra
16.
Lancet Diabetes Endocrinol ; 4(5): 447-56, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26777129

RESUMO

Growth monitoring of apparently healthy children aims at early detection of serious underlying disorders. However, existing growth-monitoring practices are mainly based on suboptimal methods, which can result in delayed diagnosis of severe diseases and inappropriate referrals. We did a systematic review to address two key and interconnected questions underlying growth monitoring: which conditions should be targeted, and how should abnormal growth be defined? We systematically searched for studies reporting algorithms for growth monitoring in children and studies comparing the performance of new WHO growth charts with that of other growth charts. Among 1556 identified citations, 69 met the inclusion criteria. Six target conditions have mainly been studied: Turner syndrome, coeliac disease, cystic fibrosis, growth hormone deficiency, renal tubular acidosis, and small for gestational age with no catch-up after 2 or 3 years. Seven algorithms to define abnormal growth have been proposed in the past 20 years, but their level of validation is low, and their overall sensitivities and specificities vary substantially; however, the Grote and Saari clinical decision rules seem the most promising. Two studies reported that WHO growth charts had poorer performance compared with other existing growth charts for early detection of target conditions. Available data suggest a large gap between the widespread implementation of growth monitoring and its level of evidence or the clinical implications of early detection of serious disorders in children. Further investigations are needed to standardise the practice of growth monitoring, with a consensus on a few priority target conditions and with internationally validated clinical decision rules to define abnormal growth, including the selection of appropriate growth charts.


Assuntos
Gráficos de Crescimento , Transtornos do Crescimento/diagnóstico , Programas de Rastreamento/normas , Algoritmos , Diagnóstico Precoce , Humanos
17.
Leuk Lymphoma ; 57(3): 700-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26122194

RESUMO

Auto-transplant of cryopreserved ovarian tissue in leukemia patients carries a risk to reintroduce malignant cells. Maturation of ovarian follicles in vitro is a promising strategy to overcome the leukemic cell contamination. The follicle development and survival in 14 cryopreserved ovarian tissues with leukemia-specific PCR marker was evaluated after 7 or 14 days culture. Minimal residual disease (MRD) quantification was assessed by real-time quantitative PCR in order to identify the MRD positive (n = 6) and negative (n = 8) samples and to monitor levels of MRD before and after culture. The morphology of ovarian follicles were studied by light microscopy. After culture, no statistical significant differences were detected in follicle densities between MRD positive- and negative samples. Ovarian MRD either decreased below undetectable or fluctuated near the baseline level after 7 and 14 days in culture. This study provides quantitative in vitro evidence that leukemia contamination does not affect the follicle survival in cryopreserved ovarian tissue.


Assuntos
Criopreservação , Preservação da Fertilidade , Leucemia/diagnóstico , Neoplasia Residual/diagnóstico , Ovário , Adolescente , Adulto , Criança , Pré-Escolar , Criopreservação/métodos , Feminino , Preservação da Fertilidade/métodos , Humanos , Leucemia/tratamento farmacológico , Leucemia/genética , Proteínas de Fusão Oncogênica/genética , Folículo Ovariano , Reação em Cadeia da Polimerase em Tempo Real , Técnicas de Cultura de Tecidos , Adulto Jovem
19.
Nat Rev Endocrinol ; 11(9): 547-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26194704

RESUMO

Congenital hypogonadotropic hypogonadism (CHH) is a rare disorder caused by the deficient production, secretion or action of gonadotropin-releasing hormone (GnRH), which is the master hormone regulating the reproductive axis. CHH is clinically and genetically heterogeneous, with >25 different causal genes identified to date. Clinically, the disorder is characterized by an absence of puberty and infertility. The association of CHH with a defective sense of smell (anosmia or hyposmia), which is found in ∼50% of patients with CHH is termed Kallmann syndrome and results from incomplete embryonic migration of GnRH-synthesizing neurons. CHH can be challenging to diagnose, particularly when attempting to differentiate it from constitutional delay of puberty. A timely diagnosis and treatment to induce puberty can be beneficial for sexual, bone and metabolic health, and might help minimize some of the psychological effects of CHH. In most cases, fertility can be induced using specialized treatment regimens and several predictors of outcome have been identified. Patients typically require lifelong treatment, yet ∼10-20% of patients exhibit a spontaneous recovery of reproductive function. This Consensus Statement summarizes approaches for the diagnosis and treatment of CHH and discusses important unanswered questions in the field.


Assuntos
Hipogonadismo/patologia , Hipogonadismo/terapia , Consenso , Europa (Continente) , Feminino , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/genética , Masculino , Maturidade Sexual
20.
JAMA Pediatr ; 169(3): e1525, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25730696

RESUMO

IMPORTANCE: Growth-monitoring programs in children aim to achieve the early detection of disorders that affect growth. Celiac disease (CD) is underdiagnosed in the pediatric population in which the presenting features often include faltering linear growth, short stature, or poor weight gain. OBJECTIVES: To develop new evidence-based cutoffs for screening for growth disorders and to evaluate the performance of these cutoffs among children with CD measured regularly in a nationwide growth screening program. DESIGN, SETTING, AND PARTICIPANTS: A longitudinal retrospective study that included longitudinal growth data of healthy children (the reference population) from primary health care and children with CD (the cases) from primary health care and 3 university hospital outpatient clinics in Finland (Kuopio University Hospital, Tampere University Hospital, and Helsinki University Hospital) from January 1, 1994, to April 9, 2009. Children of the reference population were between 0 and 20 years of age and children with CD were between 1 and 16 years of age. In the reference population of 51,332 healthy children, 5 age-specific and sex-specific growth-screening parameters (height standard deviation score and body mass index standard deviation score distance from the population mean, distance from target height, change in height standard deviation score, and change in body mass index standard deviation score) were developed. Performance of these parameters and their combination was evaluated in 177 children with CD by analyzing longitudinal growth data from birth until diagnosis of CD. MAIN OUTCOME AND MEASURE: The screening accuracy for detecting abnormal growth in children with CD, assessed using receiver operating characteristics analysis expressed as the area under the curve. RESULTS: Celiac disease was detected with good accuracy (area under the curve [95% CI] = 0.88 [0.84-0.93] for girls and 0.84 [0.77-0.91] for boys) when screening was performed using the combination of all 5 growth-screening parameters. When the specificity of the screening was set at 90%, growth was already abnormal in 57% of the girls with CD and 48% of the boys with CD 2 years prior to diagnosis. CONCLUSIONS AND RELEVANCE: Prior to diagnosis, growth faltered in most children with CD. These children could have been detected several years earlier by a well-established growth-monitoring program. Acceptable screening accuracy can be achieved for CD via the use of several growth-monitoring parameters in combination, preferably using computerized screening algorithms that are integrated into an electronic health record system.


Assuntos
Doença Celíaca/diagnóstico , Desenvolvimento Infantil , Programas de Rastreamento/métodos , Adolescente , Criança , Pré-Escolar , Diagnóstico Precoce , Feminino , Finlândia , Humanos , Estudos Longitudinais , Masculino , Sistema de Registros , Estudos Retrospectivos , Sensibilidade e Especificidade
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