Estrogens: Two nuclear receptors, multiple possibilities

Much is known about estrogen action in experimental animal models and in human physiology. This article reviews the mechanisms of estrogen activity in animals and humans and the role of its two receptors α and β in terms of structure and mechanisms of action in various tissues in health and in relationship with human pathologies (e.g., osteoporosis). Recently, the spectrum of clinical pictures of estrogen resistance caused by estrogen receptors gene variants has been widened by our description of a woman with β-receptor defect, which could be added to the already known descriptions of α-receptor defect in women and men and β-receptor defect in men. The essential role of the β-receptor in the development of the gonad stands out. We summarize the clinical pictures due to estrogen resistance in men and women and focus on long-term follow-up of two women, one with α- and the other with β-receptor resistance. Some open questions remain on the complex interactions between the two receptors on bone metabolism and hypothalamus-pituitary-gonadal axis, which need further deepening and research

Early-onset complete ovarian failure and lack of puberty in a woman with mutated estrogen receptor β (esr2)

Estrogen resistance due to mutations in the estrogen receptor α gene (ESR1) has been described in men and women and is characterized by osteoporosis, delayed bone age and continuous growth in adulthood, and delayed puberty and multiple ovarian cysts in women. Although mutations in the estrogen receptor β gene ESR2 were found in 46, XY patients with differences of sex development, no genetic variants of ESR2 were linked to gonadal defects in women.Settings and Patient: Here we describe a 16-year-old female patient who came to our tertiary care hospital with complete lack of estrogen action, as demonstrated by absent breast development, primary amenorrhea, and osteoporosis, resembling patients with ESR1 mutation. However, her gonads were clearly abnormal (streak), a finding not observed in ESR1- deficient patients.Design: To gain insights into the molecular consequences of the ESR2 defect, whole exome sequencing and extensive functional transactivation studies in ovarian, bone, and breast cells were conducted, with or without the natural activator of estrogen receptors, 17β-estradiol.Results: We identified a loss-of-function heterozygous mutation of a highly conserved residue in ESR2 that disrupts estradiol- dependent signaling and has a dominant negative effect, most likely due to failure to interact with its coactivator, nuclear coactivator 1.Conclusions: This is a report of a loss-of-function mutation in the estrogen receptor β in a young woman with complete ovarian failure, suggesting that ESR2 is necessary for human ovarian determination and/or maintenance and that ESR1 is not sufficient to sustain ovarian function in humans

Aktuelle Herausforderungen in der Therapie des Typ-1-Diabetes beim Kind

Das 1921 entdeckte Insulin wurde 1922 erstmals als Therapie für Typ-1-Diabetes eingeführt. Hundert Jahre später wird es immer noch als einzige medikamentöse Behandlung eingesetzt. Die jüngsten Fortschritte haben zu einer erheblichen Optimierung der Stoffwechselkontrolle beigetragen. Einleitung Typ-1-Diabetes (T1D) ist eine der häufigsten chronischen Erkrankungen bei Kindern, mit einer jährlichen Inzidenzzunahme von 3% [1]. Die Ätiologie des T1D ist unbekannt, aber eine Dysregulation der Autoimmunität, dokumentiert durch die Zirkulation von Autoantikörpern, sowie eine genetische Prädisposition sind ursächlich beteiligt. Das Risiko, an T1D zu erkranken, beträgt bei Kindern 0,4%; gibt es bereits an T1D-erkrankte Familienangehörige, steigt das Risiko um das Zehnfache. Neueste Daten weisen auf einen deutlichen Anstieg der weltweiten Inzidenz während der Corona-Pandemie hin [2–5]. Ziel dieses Beitrags ist es, die neuesten Entwicklungen und aktuellen Herausforderungen bei der Behandlung des T1D bei Kindern darzustellen

Loss-of-function and missense variants in NSD2 cause decreased methylation activity and are associated with a distinct developmental phenotype

PURPOSE: Despite a few recent reports of patients harboring truncating variants in NSD2, a gene considered critical for the Wolf–Hirschhorn syndrome (WHS) phenotype, the clinical spectrum associated with NSD2 pathogenic variants remains poorly understood. METHODS: We collected a comprehensive series of 18 unpublished patients carrying heterozygous missense, elongating, or truncating NSD2 variants; compared their clinical data to the typical WHS phenotype after pooling them with ten previously described patients; and assessed the underlying molecular mechanism by structural modeling and measuring methylation activity in vitro. RESULTS: The core NSD2-associated phenotype includes mostly mild developmental delay, prenatal-onset growth retardation, low body mass index, and characteristic facial features distinct from WHS. Patients carrying missense variants were significantly taller and had more frequent behavioral/psychological issues compared with those harboring truncating variants. Structural in silico modeling suggested interference with NSD2’s folding and function for all missense variants in known structures. In vitro testing showed reduced methylation activity and failure to reconstitute H3K36me2 in NSD2 knockout cells for most missense variants. CONCLUSION: NSD2 loss-of-function variants lead to a distinct, rather mild phenotype partially overlapping with WHS. To avoid confusion for patients, NSD2 deficiency may be named Rauch–Steindl syndrome after the delineators of this phenotype

A novel GATA6 variant in a boy with neonatal diabetes and diaphragmatic hernia: a familial case with a review of the literature

GATA6 gene variants come along with possible features such as pancreas agenesis/hypoplasia, neonatal diabetes and congenital heart defect. Congenital hypothyroidism, and hepatobiliary and gut abnormalities are also detectable. Children with congenital heart defects and neonatal diabetes were already described in 1970. GATA6 variants can be due to de novo variants or due to inherited variants. To date, 11 cases due to an inherited variant have been described. Herein we present a novel heterozygous GATA6 variant (c.1291C > T p.[Gln431*]) in a boy with transient neonatal diabetes, diaphragmatic hernia, congenital heart defect and early-onset scoliosis. The same variant was also present in the mother. At the age of 3 years, a random evaluation revealed a hemoglobin A1c (HbA1c) level of 7.8% (62 mmol/mol) without any diabetes-related symptoms. He was started on insulin therapy and HbA1c normalized. A short review of the literature of hereditary cases of the GATA6 variant revealed the variable phenotypic spectrum and showed that patients with a mild phenotype are likely to have children with a more severe phenotype

Double variants in TSHR and DUOX2 in a patient with hypothyroidism: case report

Thyroid dyshormonogenesis (TDH) is characterized by the defective synthesis of thyroid hormones. We present a patient with congenital hypothyroidism (CH) who presented in newborn screening with elevated serum thyroid-stimulating hormone (TSH), decreased free thyroxine (fT4) and increased thyroglobulin (Tg) concentrations. Ultrasound scan revealed a properly structured thyroid gland. Treatment with L-thyroxine was initiated. At the age of 2 years, thyroxine replacement was stopped. The patient remained untreated until 6 years of age when TSH levels progressively increased and L-thyroxine treatment was restarted at a dose of 12.5 μg/day. Genetic analysis revealed a double heterozygosity for likely pathogenic variants of dual oxidase 2 (DUOX2) and thyroid stimulating hormone receptor (TSHR). Both genes were earlier shown to be associated with CH. In a literature review, our patient was compared to previously published patients with similar clinical characteristics, and a good genotype-phenotype correlation was identified

Characteristics of Growth in Children With Classic Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency During Adrenarche and Beyond

Context: Patients with classic congenital adrenal hyperplasia (CAH) often fail to achieve their full growth potential. Adrenarche may accelerate bone maturation and thereby result in decreased growth in CAH. Objective: To analyze the impact of growth during adrenarche on final height of adequately treated classic CAH patients. Design: Retrospective, multi-center study. Setting: Four academic pediatric endocrinology centers. Participants: Fourty-one patients with classical CAH, born between 1990 and 2012. Main outcome measures: We assessed skeletal maturation (bone age), growth velocity and (projected) adult height outcomes, and analyzed potential influencing factors, such as sex, genotype, and glucocorticoid therapy. Results: Patients with classic CAH were shorter than peers (-0.4SDS±0.8SD) and their parents (corrected final height -0.6SDS±1.0SD). Analysis of growth during adrenarche revealed two different growth patterns: patients with accelerating bone age (49%), and patients with non-accelerating bone age compared to chronological age (BA-CA). Patients with accelerating BA-CA were taller than the normal population during adrenarche years (p=0.001) and were predicted to achieve a lower adult height SDS (-0.9SDS, 95%CI -1.3;-0.5) than non-accelerating patients when assessed during adrenarche (0.2SDS, 95%CI -0.3;0.8). Final adult height was similarly reduced in both accelerating and non-accelerating BA-CA groups (-0.4SDS, 95%CI -0.9;0.1 vs -0.3SDS, 95%CI -0.8;0.1). Conclusions: Patients with and without significant bone age advancement, and thus differing height prediction during adrenarche, showed similar (predicted) final height when reassessed during pubertal years. Bone age alone should not be used during adrenarche as clinical marker for metabolic control in CAH treatment. Keywords: adrenarche; classic CAH; final height prediction; growth

NOS1 mutations cause hypogonadotropic hypogonadism with sensory and cognitive deficits that can be reversed in infantile mice

The nitric oxide (NO) signaling pathway in hypothalamic neurons plays a key role in the regulation of the secretion of gonadotropin-releasing hormone (GnRH), which is crucial for reproduction. We hypothesized that a disruption of neuronal NO synthase (NOS1) activity underlies some forms of hypogonadotropic hypogonadism. Whole-exome sequencing was performed on a cohort of 341 probands with congenital hypogonadotropic hypogonadism to identify ultrarare variants in NOS1. The activity of the identified NOS1 mutant proteins was assessed by their ability to promote nitrite and cGMP production in vitro. In addition, physiological and pharmacological characterization was carried out in a Nos1-deficient mouse model. We identified five heterozygous NOS1 loss-of-function mutations in six probands with congenital hypogonadotropic hypogonadism (2%), who displayed additional phenotypes including anosmia, hearing loss, and intellectual disability. NOS1 was found to be transiently expressed by GnRH neurons in the nose of both humans and mice, and Nos1 deficiency in mice resulted in dose-dependent defects in sexual maturation as well as in olfaction, hearing, and cognition. The pharmacological inhibition of NO production in postnatal mice revealed a critical time window during which Nos1 activity shaped minipuberty and sexual maturation. Inhaled NO treatment at minipuberty rescued both reproductive and behavioral phenotypes in Nos1-deficient mice. In summary, lack of NOS1 activity led to GnRH deficiency associated with sensory and intellectual comorbidities in humans and mice. NO treatment during minipuberty reversed deficits in sexual maturation, olfaction, and cognition in Nos1 mutant mice, suggesting a potential therapy for humans with NO deficiency

Characteristics of growth in children with classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency during adrenarche and beyond.

CONTEXT Patients with classic congenital adrenal hyperplasia (CAH) often fail to achieve their full growth potential. Adrenarche may accelerate bone maturation and thereby result in decreased growth in CAH. OBJECTIVE To analyze the impact of growth during adrenarche on final height of adequately treated classic CAH patients. DESIGN Retrospective, multi-center study. SETTING Four academic pediatric endocrinology centers. PARTICIPANTS Fourty-one patients with classical CAH, born between 1990 and 2012. MAIN OUTCOME MEASURES We assessed skeletal maturation (bone age), growth velocity and (projected) adult height outcomes, and analyzed potential influencing factors, such as sex, genotype, and glucocorticoid therapy. RESULTS Patients with classic CAH were shorter than peers (-0.4SDS±0.8SD) and their parents (corrected final height -0.6SDS±1.0SD). Analysis of growth during adrenarche revealed two different growth patterns: patients with accelerating bone age (49%), and patients with non-accelerating bone age compared to chronological age (BA-CA). Patients with accelerating BA-CA were taller than the normal population during adrenarche years (p=0.001) and were predicted to achieve a lower adult height SDS (-0.9SDS, 95%CI -1.3;-0.5) than non-accelerating patients when assessed during adrenarche (0.2SDS, 95%CI -0.3;0.8). Final adult height was similarly reduced in both accelerating and non-accelerating BA-CA groups (-0.4SDS, 95%CI -0.9;0.1 vs -0.3SDS, 95%CI -0.8;0.1). CONCLUSIONS Patients with and without significant bone age advancement, and thus differing height prediction during adrenarche, showed similar (predicted) final height when reassessed during pubertal years. Bone age alone should not be used during adrenarche as clinical marker for metabolic control in CAH treatment