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Open access

Circulating aryl hydrocarbon receptor-interacting protein (AIP) is independent of GH secretion

Marko Stojanovic, Zida Wu, Craig E Stiles, Dragana Miljic, Ivan Soldatovic, Sandra Pekic, Mirjana Doknic, Milan Petakov, Vera Popovic, Christian Strasburger, and Márta Korbonits

Background

Aryl hydrocarbon receptor-interacting protein (AIP) is evolutionarily conserved and expressed widely throughout the organism. Loss-of-function AIP mutations predispose to young-onset pituitary adenomas. AIP co-localizes with growth hormone in normal and tumorous somatotroph secretory vesicles. AIP protein is detectable in circulation. We aimed to investigate possible AIP and GH co-secretion, by studying serum AIP and GH levels at baseline and after GH stimulation or suppression, in GH deficiency (GHD) and in acromegaly patients.

Subjects and methods

Insulin tolerance test (ITT) was performed in GHD patients (n = 13) and age-BMI-matched normal GH axis control patients (n = 31). Oral glucose tolerance test (OGTT) was performed in active acromegaly patients (n = 26) and age-BMI-matched normal GH axis control patients (n = 18). In-house immunometric assay was developed for measuring circulating AIP.

Results

Serum AIP levels were in the 0.1 ng/mL range independently of gender, age or BMI. Baseline AIP did not differ between GHD and non-GHD or between acromegaly and patients with no acromegaly. There was no change in peak, trough or area under the curve during OGTT or ITT. Serum AIP did not correlate with GH during ITT or OGTT.

Conclusions

Human circulating serum AIP in vivo was assessed by a novel immunometric assay. AIP levels were independent of age, sex or BMI and unaffected by hypoglycaemia or hyperglycaemia. Despite co-localization in secretory vesicles, AIP and GH did not correlate at baseline or during GH stimulation or suppression tests. A platform of reliable serum AIP measurement is established for further research of its circulatory source, role and impact.

DOI:
https://doi.org/10.1530/EC-19-0082
Volume 8: Issue 4,
Pages:
326–337 (12 total)
Open access

Prevalence of diabetes mellitus in patients with acromegaly

A V Dreval, I V Trigolosova, I V Misnikova, Y A Kovalyova, R S Tishenina, I A Barsukov, A V Vinogradova, and B H R Wolffenbuttel

Early carbohydrate metabolism disorders (ECMDs) and diabetes mellitus (DM) are frequently associated with acromegaly. We aimed to assess the prevalence of ECMDs in patients with acromegaly and to compare the results with those in adults without acromegaly using two population-based epidemiologic surveys. We evaluated 97 patients with acromegaly in several phases of their disease (mean age, 56 years and estimated duration of acromegaly, 12.5 years). An oral glucose tolerance test was done in those not yet diagnosed with DM to reveal asymptomatic DM or ECMDs (impaired glucose tolerance+impaired fasting glucose). Comparisons were made between patients with acromegaly and participants from the general adult population (n=435) and an adult population with multiple type 2 diabetes risk factors (n=314), matched for gender, age and BMI. DM was diagnosed in 51 patients with acromegaly (52.5%) and 14.3% of the general population (P<0.001). The prevalence of ECMDs was also higher in patients with acromegaly than in the general population and in the high-risk group; only 22% of patients with acromegaly were normoglycaemic. The prevalence of newly diagnosed ECMDs or DM was 1.3–1.5 times higher in patients with acromegaly compared with the high-risk group. Patients with acromegaly having ECMDs or DM were older, more obese and had longer disease duration and higher IGF1 levels (Z-score). Logistic regression showed that the severity of glucose derangement was predicted by age, BMI and IGF1 levels. In patients with acromegaly, the prevalence of DM and ECMDs considerably exceeds that of the general population and of a high-risk group, and development of DM depends on age, BMI and IGF1 levels.

DOI:
https://doi.org/10.1530/EC-14-0021
Volume 3: Issue 2,
Pages:
93–98 (6 total)
Open access

Changes in the clinical management of 5α-reductase type 2 and 17β-hydroxysteroid dehydrogenase type 3 deficiencies in France

Estelle Bonnet, Mathias Winter, Delphine Mallet, Ingrid Plotton, Claire Bouvattier, Maryse Cartigny, Laetiti Martinerie, Michel Polak, Anne Bachelot, Frédéric Huet, Sabine Baron, Muriel Houang, Sylvie Soskin, Anne Lienhardt, Jérôme Bertherat, Cyril Amouroux, Aurore Bouty, Lise Duranteau, Rémi Besson, Alaa El Ghoneimi, Dinane Samara-Boustani, François Becmeur, Nicolas Kalfa, Françoise Paris, François Medjkane, Aude Brac de la Perrière, Patricia Bretones, Hervé Lejeune, Marc Nicolino, Pierre Mouriquand, Daniela-Brindusa Gorduza, and Claire-Lise Gay

Objectives

To examine the changes in diagnostic practices and clinical management of patients with 5α-reductase type 2 (SRD5A2) or 17β-hydroxysteroid dehydrogenase type 3 (HSD17B3) deficiency since molecular diagnoses became available.

Methods

Clinical, laboratory, and therapeutic data were retrieved from the medical records of 52 patients with a molecular diagnosis of SRD5A2 (n = 31) or HSD17B3 (n = 21) deficiency. Temporal trends regarding age at assessment and initial sex assignment over 1994–2020 were qualitatively analyzed. Age at molecular diagnosis was compared between two subgroups of patients according to their year of birth.

Results

Fifty-eight percent (n = 30) patients were diagnosed during the perinatal period, 33% (n = 17) during infancy, and 9% (n = 5) during adolescence or adulthood. Over the studied period, the patients’ age at initial assessment and diagnosis frankly decreased. The median (range) age at diagnostic confirmation was 10.5 (0–53.2) years for patients born before 2007 and 0.4 (0–9.3) years for those born in 2007 or later (P = 0.029). Genetic testing identified 27 different variants for the SRD5A2 gene (30% novel, n = 8) and 18 for the HSD17B3 gene (44% novel, n = 8). Before 2002, most patients were initially assigned as females (95%, n = 19), but this proportion dropped for those born later (44%, n = 14; P < 0.001). The influence of initial genital appearance on these decisions seemingly decreased in the most recent years. Therapeutic interventions differed according to the sex of rearing. Ten percent (n = 2) patients requested female-to-male reassignment during adulthood.

Conclusion

This study showed, over the past two decades, a clear trend toward earlier diagnosis and assignment of affected newborns as males.

DOI:
https://doi.org/10.1530/EC-22-0227
Volume 12: Issue 3
Open access

Biochemical identification of prepubertal boys with Klinefelter syndrome by combined reproductive hormone profiling using machine learning

Andre Madsen, Anders Juul, and Lise Aksglaede

Objective

Klinefelter syndrome (KS) is the most common sex chromosome disorder and genetic cause of infertility in males. A highly variable phenotype contributes to the fact that a large proportion of cases are never diagnosed. Typical hallmarks in adults include small testes and azoospermia which may prompt biochemical evaluation that typically shows extremely high follicle-stimulating hormone and low/undetectable inhibin B serum concentrations. However, in prepubertal KS individuals, biochemical parameters are largely overlapping those of prepubertal controls. We aimed to characterize clinical profiles of prepubertal boys with KS in relation to controls and to develop a novel biochemical classification model to identify KS before puberty.

Methods

Retrospective, longitudinal data from 15 prepubertal boys with KS and data from 1475 controls were used to calculate age- and sex-adjusted standard deviation scores (SDS) for height and serum concentrations of reproductive hormones and used to infer a decision tree classification model for KS.

Results

Individual reproductive hormones were low but within reference ranges and did not discriminate KS from controls. Clinical and biochemical profiles including age- and sex-adjusted SDS from multiple reference curves provided input data to train a ‘random forest’ machine learning (ML) model for the detection of KS. Applied to unseen data, the ML model achieved a classification accuracy of 78% (95% CI, 61–94%).

Conclusions

Supervised ML applied to clinically relevant variables enabled computational classification of control and KS profiles. The application of age- and sex-adjusted SDS provided robust predictions irrespective of age. Specialized ML models applied to combined reproductive hormone concentrations may be useful diagnostic tools to improve the identification of prepubertal boys with KS.

DOI:
https://doi.org/10.1530/EC-22-0537
Volume 12: Issue 5
Open access

Categorization of β-cell capacity in patients with obesity via OGTT using K-means clustering

Li Li, Qifa Song, and Xi Yang

Insufficient insulin release plays a crucial role in the development of unhealthy status in patients with obesity; the present study aimed to classify these patients by the indices for insulin resistance and insulin release. After the indices from OGTT were assessed to achieve high differentiability and low redundancy in classifying patients, HOMA-IR and IGI30min were chosen to classify the patients using K-means clustering method. A total of 249 non-diabetic patients with obesity were classified into four groups. In Group 1, 19 patients were characteristic of high insulin resistance and high insulin release, as well as well-controlled glucose levels, the highest BMI, the youngest age, and the highest early phase release of insulin. In Group 2, 38 patients were unhealthiest in terms of high insulin resistance, reduced insulin release and IGT status. Group 3 consisted of 63 patients that were healthiest with low insulin resistance and high insulin release. In Group 4, 46 IGT patients and 14 IFG patients were identified among 129 patients that showed low insulin resistance, low insulin release, moderate obesity and older age. These concurrent impotent insulin release, older age, and moderate obesity indicated decreasing obesity with increasing age and reduced insulin release. The classification of patients with obesity using K-means clustering method by HOMA-IR and IGI30min provides more information about the development of obesity and unhealthy status. The patients with distinct insulin resistance and insulin release should be followed up, especially for those with reduced or even absent insulin response to glucose stimulation.

DOI:
https://doi.org/10.1530/EC-19-0476
Volume 9: Issue 2,
Pages:
135–143 (9 total)
Open access

Increased prevalence of overweight and obesity in children with X-linked hypophosphatemia

Volha V Zhukouskaya, Anya Rothenbuhler, Annamaria Colao, Carolina Di Somma, Peter Kamenický, Séverine Trabado, Dominique Prié, Christelle Audrain, Anna Barosi, Christèle Kyheng, Anne-Sophie Lambert, and Agnès Linglart

Background/aim

X-linked hypophosphatemia (XLH) is a rare disease characterized by low phosphate levels. Scientific evidence points to a link between hypophosphatemia and obesity in general population. The aim of our longitudinal observational study was to investigate the prevalence of obesity and associated factors in a large cohort of children with XLH.

Patients/methods

We studied 172 XLH-children 5–20 years of age (113 girls/59 boys). Anthropometric parameters (weight, height, and BMI) were collected at birth and during follow-up at mean ages of 5.3, 8.2, 11.3, and 15.9 years (groups 1, 2, 3, and 4, respectively). In each group, subjects were classified based on International Obesity Taskforce (IOTF) cut off values of BMI for age and sex as overweight or obese (IOTF 25–30 or ≥30 kg/m2, respectively).

Results

In each age-group, almost 1/3 of XLH-patients were classified as overweight or obese (29.4, 28.7, 27.5, and 36.7% in groups 1, 2, 3, and 4, respectively). Children without a XLH-family history had higher BMI-IOTF at every point of follow-up, compared to those with positive XLH-family history. Similarly, higher BMI-IOTF was significantly associated with treatment duration (23.3 ± 4.4 vs 23.8 ± 3.8 vs 25.2 ± 4.5 kg/m2, for subjects with treatment duration of <5, 5–10 and >10 years, respectively, P for trend = 0.025). Multiple regression analysis confirmed an association of treatment duration and lack of XLH-family history with higher BMI-IOTF.

Conclusion

One out of three of XLH-children have phenotypically unfavourable metabolic profile expressed as increased prevalence of overweight or obesity in comparison to general population. Both the lack of XLH family history and the duration of treatment increase the risk of higher BMI-IOTF. BMI should be carefully monitored in children, and later in adults, with XLH.

DOI:
https://doi.org/10.1530/EC-19-0481
Volume 9: Issue 2,
Pages:
144–153 (10 total)
Open access

Clinical data and basal gonadotropins in the diagnosis of central precocious puberty in girls

Teodoro Durá-Travé, Fidel Gallinas-Victoriano, María Malumbres-Chacon, Lotfi Ahmed-Mohamed, María Jesús Chueca -Guindulain, and Sara Berrade-Zubiri

Objective

The objective of this study was to analyze whether some auxological characteristics or a single basal gonadotropin measurement will be sufficient to distinguish the prepubertal from pubertal status.

Methods

Auxologycal characteristics were recorded and serum LH and FSH were measured by immunochemiluminescence assays before and after GnRH stimulation test in a sample of 241 Caucasian girls with breast budding between 6- and 8-years old. Peak LH levels higher than 5 IU/L were considered a pubertal response. Area under the curve, cut-off points, sensitivity, and specificity for auxologycal variables and basal gonadotropins levels were determined by receiver operating curves.

Results

There were no significant differences in age at onset, weight, height, BMI and height velocity between both groups. Bone age was significantly higher in pubertal girls (P < 0.05), although with limited discriminatory capacity. The sensitivity and specificity for the basal LH levels were 89 and 82%, respectively, for a cut off point of 0.1 IU/L. All girls in the pubertal group had a basal LH higher than 1.0 IU/L (positive predictive value of 100%). There was a wide overlap of basal FSH and LH/FSH ratio between prepubertal and pubertal girls.

Conclusions

Auxologycal characteristics should not be used only in the differential diagnosis between prepubertal from pubertal status in 6- to 8-year-old girls. We found a high specificity of a single basal LH sample and it would be useful for establishing the diagnosis of puberty in this age group, reducing the need for GnRH stimulation testing.

DOI:
https://doi.org/10.1530/EC-20-0651
Volume 10: Issue 2,
Pages:
164–170 (7 total)
Open access

Lean mass, magnesium, faecal calprotectin and glucocorticoid exposure as risk factors for low bone mineral density in inflammatory bowel disease patients

Iulia Soare, Anca Sirbu, Mihai Mircea Diculescu, Bogdan Radu Mateescu, Cristian Tieranu, Sorina Martin, Carmen Gabriela Barbu, Mirela Ionescu, and Simona Fica

Background and aim

Low bone mineral density (BMD) is a common complication in patients with inflammatory bowel disease (IBD). However, debates are ongoing with regard to the other involved factors, especially in younger patients. This study aimed to evaluate the parameters that contribute to decreased BMD, focusing on premenopausal women and men aged <50 years.

Methods

This study included 81 patients with IBD and 81 age-, sex- and BMI-matched controls. Blood tests were conducted on IBD patients, and a dual-energy X-ray absorptiometry (DXA) scan was performed on both groups.

Results

Low BMD and fragility fracture were found to be more prevalent in IBD patients than in healthy subjects (49.3% vs 23.4%, P = 0.001 and 9.8% vs 1.2%, P = 0.01, respectively). Patients with low BMD were older, with a longer disease duration, higher faecal calprotectin (FC) levels and lower magnesium and lean mass (appreciated as appendicular skeletal muscle index (ASMI)). Multiple regression analysis revealed that ASMI, age and use of glucocorticoids were the independent parameters for decreased BMD. Although 91.3% of the patients had a 25-hydroxy vitamin D level of <30 ng/mL, it was not a statistically significant factor for decreased BMD.

Conclusion

In our study, the levels of vitamin D did not seem to have an important impact on BMD. Conversely, FC, magnesium and lean mass are important factors, suggesting that good control of disease, adequate magnesium intake and increased lean mass can have a good impact on bone metabolism in patients with IBD.

DOI:
https://doi.org/10.1530/EC-21-0138
Volume 10: Issue 8,
Pages:
918–925 (8 total)
Open access

Diurnal and stress-reactive dehydroepiandrosterone levels and telomere length in youth

Andrew R Dismukes, Vanessa J Meyer, Elizabeth A Shirtcliff, Katherine P Theall, Kyle C Esteves, and Stacy S Drury

The current investigation examined the association between the aging-related biomarkers dehydroepiandrosterone (DHEA) and telomere length (TL) in community-recruited African-American youth. The examination of DHEA included stress reactive, basal and diurnal sampling, in order to elucidate the underlying physiological process that may overlap with TL. One hundred and two participants completed the Trier Social Stressor Test for children (TSST-C). TL was obtained from all youth from buccal swabs on the same day as the TSST-C. Saliva samples from 83 participants were obtained over the course of two additional days to measure waking and diurnal levels of DHEA. DHEA diurnal slope was a robust predictor of TL (B=0.516, P<0.05), while other DHEA values were not significantly associated with TL. This study is one of the first studies to examine basal, diurnal and reactivity measurements of DHEA in youth. Furthermore, this is the first study, to our knowledge, to demonstrate a positive association between DHEA, a putative anti-aging hormone, and TL, an indicator of cellular aging.

DOI:
https://doi.org/10.1530/EC-16-0007
Volume 5: Issue 3,
Pages:
107–114 (8 total)
Open access

Interrelationships among reproductive hormones and antral follicle count in human menstrual cycles

David Mark Robertson, Chel Hee Lee, and Angela Baerwald

It is recognised that ovarian factors, including steroid and protein hormones, are critical in the feedback regulation of pituitary gonadotropins; however, their individual contributions are less defined. The aim of this study was to explore the reciprocal relationships between ovarian and pituitary hormones across the normal ovulatory menstrual cycle as women age. FSH, LH, oestradiol, progesterone, inhibin A, inhibin B and anti-mullerian hormone (AMH) were measured in serum collected every 1–3 days across one interovulatory interval (IOI) from 26 healthy women aged 18–50 years. The antral follicle count (AFC) for follicles 2–5 mm, >6 mm and 2–10 mm were tabulated across the IOI. Independent associations between ovarian hormones/AFC vs pituitary follicle-stimulating hormone (FSH) and luteinising hormone (LH) were investigated using multivariate regression analysis. The data were sub-grouped based on the presence or absence luteal phase-dominant follicles (LPDF). Serum oestradiol and AMH were inversely correlated with FSH in both follicular and luteal phases. Inhibin B correlated inversely with FSH and LH in the late follicular phase and directly in the luteal phase. AFC, inhibin A and progesterone were not key predictors of either FSH or LH. The strong association between AMH and FSH with age implies that AMH, as well as oestradiol and inhibin B are important regulators of FSH. The change in feedback response of inhibin B with both FSH and LH across the cycle suggests two phases of the negative feedback.

DOI:
https://doi.org/10.1530/EC-16-0077
Volume 5: Issue 6,
Pages:
98–107 (10 total)