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1.
Int J Mol Sci ; 25(6)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38542117

RESUMEN

Rabson-Mendenhall syndrome (RMS) is a rare autosomal recessive disorder characterized by severe insulin resistance, resulting in early-onset diabetes mellitus. We report the first case of RMS in a Paraguayan patient. The patient is a 6-year-old girl who presented with hypertrichosis, acanthosis nigricans, nephrocalcinosis, and elevated levels of glucose and insulin that served as diagnostic indicators for RMS. Genetic testing by next-generation sequencing (NGS) revealed two pathogenic variants in exons 2 and 19 of the INSR gene: c.332G>T (p.Gly111Val) and c.3485C>T (p.Ala1162Val), in combined heterozygosis. The novel INSR c. 332G>T variant leads to the substitution of glycine to valine at position 111 in the protein, and multiple in silico software programs predicted it as pathogenic. The c.3485C>T variant leads to the substitution of alanine to valine at position 1162 in the protein previously described for insulin resistance and RMS. The management of RMS is particularly challenging in children, and the use of metformin is often limited by its side effects. The patient was managed with nutritional measures due to the early age of onset. This report expands the knowledge of RMS to the Paraguayan population and adds a novel pathogenic variant to the existing literature.


Asunto(s)
Síndrome de Donohue , Resistencia a la Insulina , Niño , Femenino , Humanos , Síndrome de Donohue/diagnóstico , Resistencia a la Insulina/genética , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Mutación , Valina/genética , Antígenos CD/genética
2.
Rev Endocr Metab Disord ; 24(1): 5-21, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36255414

RESUMEN

The adrenal cortex undergoes multiple structural and functional rearrangements to satisfy the systemic needs for steroids during fetal life, postnatal development, and adulthood. A fully functional adrenal cortex relies on the proper subdivision in regions or 'zones' with distinct but interconnected functions, which evolve from the early embryonic stages to adulthood, and rely on a fine-tuned gene network. In particular, the steroidogenic activity of the fetal adrenal is instrumental in maintaining normal fetal development and growth. Here, we review and discuss the most recent advances in our understanding of embryonic and fetal adrenal development, including the known causes for adrenal dys-/agenesis, and the steroidogenic pathways that link the fetal adrenal with the hormone system of the mother through the fetal-placental unit. Finally, we discuss what we think are the major open questions in the field, including, among others, the impact of osteocalcin, thyroid hormone, and other hormone systems on adrenal development and function, and the reliability of rodents as models of adrenal pathophysiology.


Asunto(s)
Corteza Suprarrenal , Placenta , Embarazo , Femenino , Humanos , Reproducibilidad de los Resultados , Corteza Suprarrenal/fisiología , Corticoesteroides
3.
Curr Opin Pediatr ; 33(6): 556-563, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34654048

RESUMEN

PURPOSE OF REVIEW: The aim of this study was to provide a basic overview on human sex development with a focus on involved genes and pathways, and also to discuss recent advances in the molecular diagnostic approaches applied to clinical workup of individuals with a difference/disorder of sex development (DSD). RECENT FINDINGS: Rapid developments in genetic technologies and bioinformatics analyses have helped to identify novel genes and genomic pathways associated with sex development, and have improved diagnostic algorithms to integrate clinical, hormonal and genetic data. Recently, massive parallel sequencing approaches revealed that the phenotype of some DSDs might be only explained by oligogenic inheritance. SUMMARY: Typical sex development relies on very complex biological events, which involve specific interactions of a large number of genes and pathways in a defined spatiotemporal sequence. Any perturbation in these genetic and hormonal processes may result in atypical sex development leading to a wide range of DSDs in humans. Despite the huge progress in the understanding of molecular mechanisms underlying DSDs in recent years, in less than 50% of DSD individuals, the genetic cause is currently solved at the molecular level.


Asunto(s)
Trastornos del Desarrollo Sexual , Desarrollo Sexual , Trastornos del Desarrollo Sexual/diagnóstico , Trastornos del Desarrollo Sexual/genética , Genómica , Humanos , Fenotipo , Desarrollo Sexual/genética
4.
Acta Paediatr ; 110(8): 2424-2429, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33615554

RESUMEN

AIM: This study assessed lifestyle-related risk factors for cardiovascular disease in young women with Turner syndrome. METHODS: In 2012, we sent a questionnaire to women with Turner syndrome aged ≥18 years and living in Switzerland with questions on socio-demographic and medical data as well as health behaviour. We compared the reported lifestyle with that of women from the Swiss Health Survey 2012, a representative survey of the general population. RESULTS: Fifty-seven per cent (45/79) of women with Turner syndrome answered the questionnaire (mean age: 24 years). Eighty per cent (36/45) had never smoked compared with 58% (1156/1972) of the general population (p < 0.01). Women with Turner syndrome engaged less often in binge drinking (34% vs. 71%) (p < 0.001), but consumed alcohol equally often as the general population (p = 0.327). They performed sports as often as the general population (p = 0.34), but only one quarter (11/45) of women with Turner syndrome adhered to official physical activity recommendations. CONCLUSION: Although most women with Turner syndrome had a healthy lifestyle, only a minority had sufficient physical activity. Paediatricians should promote structured physical activity in girls with Turner syndrome from early childhood onwards to reduce their cardiovascular risk in adulthood and to increase long-term health-related quality of life.


Asunto(s)
Síndrome de Turner , Adolescente , Adulto , Preescolar , Femenino , Conductas Relacionadas con la Salud , Humanos , Estilo de Vida , Calidad de Vida , Suiza , Síndrome de Turner/complicaciones , Síndrome de Turner/epidemiología , Adulto Joven
5.
Int J Mol Sci ; 22(4)2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33567726

RESUMEN

Steroid hormones play a crucial role in supporting a successful pregnancy and ensuring proper fetal development. The placenta is one of the principal tissues in steroid production and metabolism, expressing a vast range of steroidogenic enzymes. Nevertheless, a comprehensive characterization of steroidogenic pathways in the human placenta and potential developmental changes occurring during gestation are poorly understood. Furthermore, the specific contribution of trophoblast cells in steroid release is largely unknown. Thus, this study aimed to (i) identify gestational age-dependent changes in the gene expression of key steroidogenic enzymes and (ii) explore the role of trophoblast cells in steroid biosynthesis and metabolism. Quantitative and Droplet Digital PCR analysis of 12 selected enzymes was carried out in the first trimester (n = 13) and term (n = 20) human placentas. Primary trophoblast cells (n = 5) isolated from human term placentas and choriocarcinoma-derived cell lines (BeWo, BeWo b30 clone, and JEG-3) were further screened for gene expression of enzymes involved in placental synthesis/metabolism of steroids. Finally, de novo steroid synthesis by primary human trophoblasts was evaluated, highlighting the functional activity of steroidogenic enzymes in these cells. Collectively, we provide insights into the expression patterns of steroidogenic enzymes as a function of gestational age and delineate the cellular origin of steroidogenesis in the human placenta.


Asunto(s)
Coriocarcinoma/metabolismo , Regulación de la Expresión Génica , Placenta/metabolismo , Primer Trimestre del Embarazo/metabolismo , Esteroide Hidroxilasas/metabolismo , Esteroides/metabolismo , Trofoblastos/metabolismo , Adulto , Células Cultivadas , Coriocarcinoma/patología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Placenta/citología , Embarazo , Esteroide Hidroxilasas/genética , Trofoblastos/citología
6.
Clin Infect Dis ; 71(4): 1030-1039, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-31633158

RESUMEN

BACKGROUND: Perinatal treatment with lopinavir boosted by ritonavir (LPV/r) is associated with steroidogenic abnormalities. Long-term effects in infants have not been studied. METHODS: Adrenal-hormone profiles were compared at weeks 6 and 26 between human immunodeficiency virus (HIV)-1-exposed but uninfected infants randomly assigned at 7 days of life to prophylaxis with LPV/r or lamivudine (3TC) to prevent transmission during breastfeeding. LPV/r in vitro effect on steroidogenesis was assessed in H295R cells. RESULTS: At week 6, 159 frozen plasma samples from Burkina Faso and South Africa were assessed (LPV/r group: n = 92; 3TC group: n = 67) and at week 26, 95 samples from Burkina Faso (LPV/r group: n = 47; 3TC group: n = 48). At week 6, LPV/r-treated infants had a higher median dehydroepiandrosterone (DHEA) level than infants from the 3TC arm: 3.91 versus 1.48 ng/mL (P < .001). Higher DHEA levels (>5 ng/mL) at week 6 were associated with higher 17-OH-pregnenolone (7.78 vs 3.71 ng/mL, P = .0004) and lower testosterone (0.05 vs 1.34 ng/mL, P = .009) levels in LPV/r-exposed children. There was a significant correlation between the DHEA and LPV/r AUC levels (ρ = 0.40, P = .019) and Ctrough (ρ = 0.40, P = .017). At week 26, DHEA levels remained higher in the LPV/r arm: 0.45 versus 0.13 ng/mL (P = .002). Lopinavir, but not ritonavir, inhibited CYP17A1 and CYP21A2 activity in H295R cells. CONCLUSIONS: Lopinavir was associated with dose-dependent adrenal dysfunction in infants. The impact of long-term exposure and potential clinical consequences require evaluation. CLINICAL TRIALS REGISTRATION: NCT00640263.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/efectos adversos , Burkina Faso , Niño , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Lactante , Lopinavir/uso terapéutico , Embarazo , Ritonavir/efectos adversos , Sudáfrica , Esteroide 21-Hidroxilasa
7.
Int J Mol Sci ; 21(23)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33266346

RESUMEN

Disorders (or differences) of sex development (DSD) are congenital conditions characterized by atypical development of genetic, gonadal or phenotypic sex [...].


Asunto(s)
Mamíferos , Desarrollo Sexual/fisiología , Animales , Susceptibilidad a Enfermedades , Trastornos del Desarrollo Sexual/etiología , Humanos , Procesos de Determinación del Sexo
8.
Int J Mol Sci ; 21(5)2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155719

RESUMEN

Sex development is a very complex biological event that requires the concerted collaboration of a large network of genes in a spatial and temporal correct fashion. In the past, much has been learned about human sex development from monogenic disorders/differences of sex development (DSD), but the broad spectrum of phenotypes in numerous DSD individuals remains a conundrum. Currently, the genetic cause of less than 50% of DSD individuals has been solved and oligogenic disease has been proposed. In recent years, multiple genetic hits have been found in individuals with DSD thanks to high throughput sequencing. Our group has been searching for additional genetic hits explaining the phenotypic variability over the past years in two cohorts of patients: 46,XY DSD patients carriers of NR5A1 variants and 46,XY DSD and 46,XX DSD with MAMLD1 variants. In both cohorts, our results suggest that the broad phenotypes may be explained by oligogenic origin, in which multiple hits may contribute to a DSD phenotype, unique to each individual. A search for an underlying network of the identified genes also revealed that a considerable number of these genes showed interactions, suggesting that genetic variations in these genes may affect sex development in concert.


Asunto(s)
Trastornos del Desarrollo Sexual/genética , Trastornos del Desarrollo Sexual/patología , Variación Genética , Proteínas Nucleares/genética , Factores de Transcripción/genética , Femenino , Humanos , Masculino , Fenotipo
9.
Int J Mol Sci ; 21(16)2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32824094

RESUMEN

Classical congenital adrenal hyperplasia (CAH) caused by pathogenic variants in the steroid 21-hydroxylase gene (CYP21A2) is a severe life-threatening condition. We present a detailed investigation of the molecular and functional characteristics of a novel pathogenic variant in this gene. The patient, 46 XX newborn, was diagnosed with classical salt wasting CAH in the neonatal period after initially presenting with ambiguous genitalia. Multiplex ligation-dependent probe analysis demonstrated a full deletion of the paternal CYP21A2 gene, and Sanger sequencing revealed a novel de novo CYP21A2 variant c.694-696del (E232del) in the other allele. This variant resulted in the deletion of a non-conserved single amino acid, and its functional relevance was initially undetermined. We used both in silico and in vitro methods to determine the mechanistic significance of this mutation. Computational analysis relied on the solved structure of the protein (Protein-data-bank ID 4Y8W), structure prediction of the mutated protein, evolutionary analysis, and manual inspection. We predicted impaired stability and functionality of the protein due to a rotatory disposition of amino acids in positions downstream of the deletion. In vitro biochemical evaluation of enzymatic activity supported these predictions, demonstrating reduced protein levels to 22% compared to the wild-type form and decreased hydroxylase activity to 1-4%. This case demonstrates the potential of combining in-silico analysis based on evolutionary information and structure prediction with biochemical studies. This approach can be used to investigate other genetic variants to understand their potential effects.


Asunto(s)
Simulación por Computador , Mutación/genética , Esteroide 21-Hidroxilasa/química , Esteroide 21-Hidroxilasa/genética , Preescolar , Evolución Molecular , Femenino , Humanos , Lactante , Recién Nacido
10.
Int J Mol Sci ; 21(17)2020 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-32867102

RESUMEN

Congenital adrenal hyperplasia (CAH) consists of several autosomal recessive disorders that inhibit steroid biosynthesis. We describe a case report diagnosed with adrenal insufficiency due to low adrenal steroids and adrenocorticotropic hormone excess due to lack of cortisol negative feedback signaling to the pituary gland. Genetic work up revealed two missense variants, p.Thr204Arg and p.Leu260Arg in the STAR gene, inherited by both parents (non-consanguineous). The StAR protein supports CYP11A1 enzyme to cleave the side chain of cholesterol and synthesize pregnenolone which is metabolized to all steroid hormones. We used bioinformatics to predict the impact of the variants on StAR activity and then we performed functional tests to characterize the two novel variants. In a cell system we tested the ability of variants to support cholesterol conversion to pregnenolone and measured their mRNA and protein expression. For both variants, we observed loss of StAR function, reduced protein expression and categorized them as pathogenic variants according to guidelines of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. These results fit the phenotype of the girl during diagnosis. This study characterizes two novel variants and expands the list of missense variants that cause CAH.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Mutación Missense , Fosfoproteínas/química , Fosfoproteínas/genética , Hiperplasia Suprarrenal Congénita/metabolismo , Animales , Células COS , Chlorocebus aethiops , Colesterol/metabolismo , Trastorno del Desarrollo Sexual 46,XY/metabolismo , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Masculino , Modelos Moleculares , Linaje , Pregnenolona/metabolismo , Conformación Proteica
11.
Int J Mol Sci ; 21(22)2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33202802

RESUMEN

Variants of NR5A1 are often found in individuals with 46,XY disorders of sex development (DSD) and manifest with a very broad spectrum of clinical characteristics and variable sex hormone levels. Such complex phenotypic expression can be due to the inheritance of additional genetic hits in DSD-associated genes that modify sex determination, differentiation and organ function in patients with heterozygous NR5A1 variants. Here we describe the clinical, biochemical and genetic features of a series of seven patients harboring monoallelic variants in the NR5A1 gene. We tested the transactivation activity of novel NR5A1 variants. We additionally included six of these patients in a targeted diagnostic gene panel for DSD and identified a second genetic hit in known DSD-causing genes STAR, AMH and ZFPM2/FOG2 in three individuals. Our study increases the number of NR5A1 variants related to 46,XY DSD and supports the hypothesis that a digenic mode of inheritance may contribute towards the broad spectrum of phenotypes observed in individuals with a heterozygous NR5A1 variation.


Asunto(s)
Proteínas de Unión al ADN/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Variación Genética , Heterocigoto , Herencia Multifactorial , Fosfoproteínas/genética , Receptores de Péptidos/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Factor Esteroidogénico 1/genética , Factores de Transcripción/genética , Adolescente , Niño , Preescolar , Trastorno del Desarrollo Sexual 46,XY/patología , Femenino , Humanos , Lactante , Recién Nacido , Masculino
12.
Genet Med ; 20(8): 872-881, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29144511

RESUMEN

PURPOSE: Congenital hypogonadotropic hypogonadism (CHH), a rare genetic disease caused by gonadotropin-releasing hormone deficiency, can also be part of complex syndromes (e.g., CHARGE syndrome). CHD7 mutations were reported in 60% of patients with CHARGE syndrome, and in 6% of CHH patients. However, the definition of CHD7 mutations was variable, and the associated CHARGE signs in CHH were not systematically examined. METHODS: Rare sequencing variants (RSVs) in CHD7 were identified through exome sequencing in 116 CHH probands, and were interpreted according to American College of Medical Genetics and Genomics guidelines. Detailed phenotyping was performed in CHH probands who were positive for CHD7 RSVs, and genotype-phenotype correlations were evaluated. RESULTS: Of the CHH probands, 16% (18/116) were found to harbor heterozygous CHD7 RSVs, and detailed phenotyping was performed in 17 of them. Of CHH patients with pathogenic or likely pathogenic CHD7 variants, 80% (4/5) were found to exhibit multiple CHARGE features, and 3 of these patients were reclassified as having CHARGE syndrome. In contrast, only 8% (1/12) of CHH patients with nonpathogenic CHD7 variants exhibited multiple CHARGE features (P = 0.01). CONCLUSION: Pathogenic or likely pathogenic CHD7 variants rarely cause isolated CHH. Therefore a detailed clinical investigation is indicated to clarify the diagnosis (CHH versus CHARGE) and to optimize clinical management.


Asunto(s)
Síndrome CHARGE/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Hipogonadismo/genética , Síndrome CHARGE/diagnóstico , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/metabolismo , Familia , Femenino , Estudios de Asociación Genética , Variación Genética/genética , Heterocigoto , Humanos , Masculino , Mutación , Linaje , Fenotipo , Análisis de Secuencia de ADN
14.
Eur J Pediatr ; 175(12): 2007-2010, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27631591

RESUMEN

Transplantation of cryopreserved ovarian tissue has been shown to successfully induce pregnancies. Furthermore, puberty may be induced by transplanted ovarian tissue in girls suffering from premature primary ovarian insufficiency (PPOI) due to gonadotoxic therapy. Therefore, the question arises if ovarian tissue cryopreservation should be recommended for puberty induction in prepubertal girls with cancer prior to gonadotoxic therapies. Although this strategy seems to be more natural than administering exogenous steroid sex hormones, there are some disadvantages from the endocrinological point of view. During physiologic puberty, serum estradiol levels increase very slowly, followed by irregular and finally regular ovulations with progesterone production during the luteal phase. PPOI presents as hypergonadotrophic hypogonadism. When transplanting ovarian tissue in girls with PPOI, the elevated gonadotrophins will promote a sudden follicular growth of one or several follicles with a sharp increase of serum estrogen levels and regular ovulations. This will result into an accelerated pubertal development with the risk of overt weight gain, cutaneous striae and premature growth stop possibly leading to psychological implications. CONCLUSION: Transplantation of cryopreserved ovarian tissue should not be recommended as an alternative to medically induced puberty.


Asunto(s)
Criopreservación , Ovario/trasplante , Insuficiencia Ovárica Primaria/cirugía , Niño , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Infertilidad Femenina/inducido químicamente , Pubertad/fisiología , Trasplante Autólogo/efectos adversos
15.
Gynecol Endocrinol ; 31(5): 349-54, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25585547

RESUMEN

BACKGROUND: Aromatase deficiency may result in a complete block of estrogen synthesis because of the failure to convert androgens to estrogens. In females, this results in virilisation at birth, ovarian cysts in prepuberty and lack of pubertal development but virilisation, thereafter. OBJECTIVE AND METHODS: We studied the impact of oral 17ß-estradiol treatment on ovarian and uterine development, and on LH/FSH and inhibin B during the long-term follow-up of a girl harboring compound heterozygote point mutations in the CYP19A1 gene. RESULTS: In early childhood, low doses of oral 17ß-estradiol were needed. During prepuberty treatment with slowly increasing doses of E2 resulted in normal uterine and almost normal development of ovarian volume, as well as number and size of follicles. Regarding hormonal feedback mechanisms, inhibin B levels were in the upper normal range during childhood and puberty. Low doses of estradiol did not suffice to achieve physiological gonadotropin levels in late prepuberty and puberty. However, when estradiol doses were further increased in late puberty levels of both FSH and LH declined with estradiol levels within normal range. CONCLUSION: Complete aromatase deficiency provides an excellent model of how ovarian and uterine development in relation to E2, LH, FSH and inhibin B feedback progresses from infancy to adolescence.


Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/tratamiento farmacológico , Aromatasa/deficiencia , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno/métodos , Estrógenos/uso terapéutico , Ginecomastia/tratamiento farmacológico , Infertilidad Masculina/tratamiento farmacológico , Errores Innatos del Metabolismo/tratamiento farmacológico , Ovario/crecimiento & desarrollo , Útero/crecimiento & desarrollo , Trastornos del Desarrollo Sexual 46, XX/metabolismo , Administración Oral , Adolescente , Aromatasa/genética , Aromatasa/metabolismo , Niño , Preescolar , Femenino , Hormona Folículo Estimulante/metabolismo , Ginecomastia/metabolismo , Humanos , Lactante , Infertilidad Masculina/metabolismo , Inhibinas/metabolismo , Hormona Luteinizante/metabolismo , Errores Innatos del Metabolismo/metabolismo , Estudios Retrospectivos
16.
Am J Hum Genet ; 89(2): 201-18, 2011 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-21802064

RESUMEN

Human sexual determination is initiated by a cascade of genes that lead to the development of the fetal gonad. Whereas development of the female external genitalia does not require fetal ovarian hormones, male genital development requires the action of testicular testosterone and its more potent derivative dihydrotestosterone (DHT). The "classic" biosynthetic pathway from cholesterol to testosterone in the testis and the subsequent conversion of testosterone to DHT in genital skin is well established. Recently, an alternative pathway leading to DHT has been described in marsupials, but its potential importance to human development is unclear. AKR1C2 is an enzyme that participates in the alternative but not the classic pathway. Using a candidate gene approach, we identified AKR1C2 mutations with sex-limited recessive inheritance in four 46,XY individuals with disordered sexual development (DSD). Analysis of the inheritance of microsatellite markers excluded other candidate loci. Affected individuals had moderate to severe undervirilization at birth; when recreated by site-directed mutagenesis and expressed in bacteria, the mutant AKR1C2 had diminished but not absent catalytic activities. The 46,XY DSD individuals also carry a mutation causing aberrant splicing in AKR1C4, which encodes an enzyme with similar activity. This suggests a mode of inheritance where the severity of the developmental defect depends on the number of mutations in the two genes. An unrelated 46,XY DSD patient carried AKR1C2 mutations on both alleles, confirming the essential role of AKR1C2 and corroborating the hypothesis that both the classic and alternative pathways of testicular androgen biosynthesis are needed for normal human male sexual differentiation.


Asunto(s)
Andrógenos/biosíntesis , Vías Biosintéticas , Feto/metabolismo , Diferenciación Sexual , Testículo/embriología , Testículo/metabolismo , Empalme Alternativo/genética , Secuencia de Aminoácidos , Secuencia de Bases , Dihidrotestosterona/metabolismo , Familia , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Hidroxiesteroide Deshidrogenasas/química , Hidroxiesteroide Deshidrogenasas/genética , Hidroxiesteroide Deshidrogenasas/metabolismo , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Mutantes/metabolismo , Mutación/genética , Oxidorreductasas/química , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Linaje
17.
Clin Endocrinol (Oxf) ; 80(2): 191-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23859637

RESUMEN

OBJECTIVE: The steroidogenic acute regulatory protein (StAR) transports cholesterol to the mitochondria for steroidogenesis. Loss of StAR function causes lipoid congenital adrenal hyperplasia (LCAH) which is characterized by impaired synthesis of adrenal and gonadal steroids causing adrenal insufficiency, 46,XY disorder of sex development (DSD) and failure of pubertal development. Partial loss of StAR activity may cause adrenal insufficiency only. PATIENT: A newborn girl was admitted for mild dehydration, hyponatremia, hyperkalemia and hypoglycaemia and had normal external female genitalia without hyperpigmentation. Plasma cortisol, 17OH-progesterone, DHEA-S, androstendione and aldosterone were low, while ACTH and plasma renin activity were elevated, consistent with the diagnosis of primary adrenal insufficiency. Imaging showed normal adrenals, and cytogenetics revealed a 46,XX karyotype. She was treated with fluids, hydrocortisone and fludrocortisone. DESIGN, METHODS AND RESULTS: Genetic studies revealed a novel homozygous STAR mutation in the 3' acceptor splice site of intron 4, c.466-1G>A (IVS4-1G>A). To test whether this mutation would affect splicing, we performed a minigene experiment with a plasmid construct containing wild-type or mutant StAR gDNA of exons-introns 4-6 in COS-1 cells. The splicing was assessed on total RNA using RT-PCR for STAR cDNAs. The mutant STAR minigene skipped exon 5 completely and changed the reading frame. Thus, it is predicted to produce an aberrant and shorter protein (p.V156GfsX19). Computational analysis revealed that this mutant protein lacks wild-type exons 5-7 which are essential for StAR-cholesterol interaction. CONCLUSIONS: STAR c.466-1A skips exon 5 and causes a dramatic change in the C-terminal sequence of the protein, which is essential for StAR-cholesterol interaction. This splicing mutation is a loss-of-function mutation explaining the severe phenotype of our patient. Thus far, all reported splicing mutations of STAR cause a severe impairment of protein function and phenotype.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Empalme Alternativo/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Mutación , Fosfoproteínas/genética , Hiperplasia Suprarrenal Congénita/patología , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/genética , Animales , Sitios de Unión/genética , Células COS , Chlorocebus aethiops , Colesterol/química , Colesterol/metabolismo , Trastorno del Desarrollo Sexual 46,XY/patología , Exones/genética , Femenino , Humanos , Recién Nacido , Modelos Moleculares , Fenotipo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Unión Proteica , Estructura Terciaria de Proteína
18.
J Clin Endocrinol Metab ; 109(6): 1403-1422, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38181424

RESUMEN

CONTEXT: Adrenarche marks the timepoint of human adrenal development when the cortex starts secreting androgens in increasing amounts, in healthy children at age 8-9 years, with premature adrenarche (PA) earlier. Because the molecular regulation and significance of adrenarche are unknown, this prepubertal event is characterized descriptively, and PA is a diagnosis by exclusion with unclear long-term consequences. EVIDENCE ACQUISITION: We searched the literature of the past 5 years, including original articles, reviews, and meta-analyses from PubMed, ScienceDirect, Web of Science, Embase, and Scopus, using search terms adrenarche, pubarche, DHEAS, steroidogenesis, adrenal, and zona reticularis. EVIDENCE SYNTHESIS: Numerous studies addressed different topics of adrenarche and PA. Although basic studies on human adrenal development, zonation, and zona reticularis function enhanced our knowledge, the exact mechanism leading to adrenarche remains unsolved. Many regulators seem involved. A promising marker of adrenarche (11-ketotestosterone) was found in the 11-oxy androgen pathway. By current definition, the prevalence of PA can be as high as 9% to 23% in girls and 2% to 10% in boys, but only a subset of these children might face related adverse health outcomes. CONCLUSION: New criteria for defining adrenarche and PA are needed to identify children at risk for later disease and to spare children with a normal variation. Further research is therefore required to understand adrenarche. Prospective, long-term studies should characterize prenatal or early postnatal developmental pathways that modulate trajectories of birth size, early postnatal growth, childhood overweight/obesity, adrenarche and puberty onset, and lead to abnormal sexual maturation, fertility, and other adverse outcomes.


Asunto(s)
Adrenarquia , Humanos , Adrenarquia/fisiología , Niño , Pubertad Precoz , Femenino , Masculino , Zona Reticular/metabolismo , Zona Reticular/crecimiento & desarrollo
19.
Horm Res Paediatr ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38852580

RESUMEN

BACKGROUND: Normal hypothalamic-pituitary-ovarian (HPO) endocrine function is essential for female pubertal and psychosocial development and for ongoing adult physical, sexual and psychosocial health. Girls with hypogonadism, any endocrine disorder causing abnormal uterine bleeding (AUB) or with contraception needs may require sex hormone treatment. Challenges include evolving needs of a young girl through the course of sexual maturation, potential health risks related to the use of sex hormones for pubertal induction, hormone replacement therapy (HRT), menstrual management and/or contraception. SUMMARY: To ensure optimal sex hormone treatment, both a comprehensive understanding of the underlying disorder affecting HPO endocrine function and a professional communication with the patient and physicians involved are warranted. In this narrative mini-review, we discuss pubertal induction and HRT for girls with hypogonadism and the management of AUB and contraception for young women up to age 30 years. Additionally, we provide advice on management of AUB and contraception in young women with common conditions including polycystic ovary syndrome, congenital adrenal hyperplasia and others. A PubMed-literature search including articles published over the last 20 years, together with clinical experience of the authors was integrated to provide treatment recommendations. KEY MESSAGE: Sex hormone treatment, where needed, requires comprehensive understanding of a range of available options. When tailored to individual needs, with flexibility to accommodate changing circumstance in young women it is safe, well tolerated and provides both physical and psychosocial health.

20.
Mol Cell Endocrinol ; 592: 112293, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38838762

RESUMEN

CONTEXT: Adrenarche is a normal developmental event in mid-childhood characterized by increasing adrenal androgen secretion. The role of the classic androgen pathway has been well described in adrenarche, but the role of newer active androgens and additional androgen pathways is less clear. OBJECTIVE: To study the contribution of novel androgens and related steroid biosynthesis pathways to the development of adrenarche, and to identify additional steroid biomarkers of adrenarche. DESIGN: A longitudinal study of children aged 6-8 years at baseline, followed up at ages 8-10 and 14-16 years. A total of 34 children (20 girls) with clinical and/or biochemical signs of adrenarche (cases) and 24 children (11 girls) without these signs (controls) at age 8-10 years were included. Serum steroid profiling was performed by liquid chromatography high-resolution mass spectrometry. MAIN OUTCOME MEASURES: Thirty-two steroids compartmentalized in progestagens, gluco- and mineralocorticoid pathways, and four androgen related pathways, including the classic, backdoor, 11-oxy, and 11-oxy backdoor pathways. RESULTS: The classic and 11-oxy androgen pathways were more active, and serum concentrations of main androgens in the classic (dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione and androsterone) and 11-oxy (11ß-hydroxyandrostenedione, 11ß-hydroxytestosterone, 11-ketoandrostenedione, and 11-ketotestosterone) pathways were higher in cases at ages 6-8 and 8-10 years. Pregnenolone concentrations at adrenarchal age (8-10 years) and cortisol concentrations at adolescence (14-16 years) were higher in cases. 11ß-hydroxyandrosterone and 11-ketoandrosterone tended to be higher in cases with clinical signs compared to cases who had only biochemical evidence of adrenarche, albeit they were detected at low levels. In biomarker analyses, calculated steroid ratios with cortisol, cortisone, or 11-deoxycortisone as dividers were better classifiers for adrenarche than single steroids. Among these ratios, androstenedione/cortisone was the best. CONCLUSIONS: The classic and 11-oxy androgen pathways are active in adrenarche. Children with earlier timing of adrenarche have higher serum cortisol levels at late pubertal age, suggesting that early adrenarche might have long-term effects on adrenal steroidogenesis by increasing the activity of the glucocorticoid pathway. Future studies should employ comprehensive steroid profiling to define novel classifiers and biomarkers for adrenarche and premature adrenarche.

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