Browse

You are looking at 41 - 50 of 20,127 items for

  • All content x
Clear All
Restricted access

Camille Sollier, Emilie Capel, Caroline Aguilhon, Vasily Smirnov, Martine Auclair, Claire Douillard, Miriam Ladsous, Sabine Defoort-Dhellemmes, Jennifer Gorwood, Laura Braud, Roberto Motterlini, Camille Vatier, Olivier Lascols, Eric Renard, Corinne Vigouroux, and Isabelle Jéru

Objective

The term Multiple Symmetric Lipomatosis (MSL) describes a heterogeneous group of rare monogenic disorders and multifactorial conditions, characterized by upper-body adipose masses. Biallelic variants in LIPE encoding hormone-sensitive lipase (HSL), a key lipolytic enzyme, were implicated in three families worldwide. We aimed to further delineate LIPE-related clinical features and pathophysiological determinants.

Methods

A gene panel was used to identify pathogenic variants. The disease features were reviewed at the French lipodystrophy reference center. The immunohistological, ultrastructural, and protein expression characteristics of lipomatous tissue were determined in surgical samples from one patient. The functional impact of variants was investigated by developing a model of adipose stem cells (ASCs) isolated from lipomatous tissue.

Results

We identified new biallelic LIPE null variants in three unrelated patients referred for MSL and/or partial lipodystrophy. The hallmarks of the disease, appearing in adulthood, included lower-limb lipoatrophy, upper-body and abdominal pseudo-lipomatous masses, diabetes and/or insulin resistance, hypertriglyceridemia, liver steatosis, high blood pressure, and neuromuscular manifestations. Ophthalmological investigations revealed numerous auto-fluorescent drusen-like retinal deposits in all patients. Lipomatous tissue and patient ASCs showed loss of HSL and decreased expression of adipogenic and mature adipocyte markers. LIPE-mutated ASCs displayed impaired adipocyte differentiation, decreased insulin response, defective lipolysis, and mitochondrial dysfunction.

Conslusions

Biallelic LIPE null variants result in a multisystemic disease requiring multidisciplinary care. Loss of HSL expression impairs adipocyte differentiation, consistent with the lipodystrophy/MSL phenotype and associated metabolic complications. Detailed ophthalmological examination could reveal retinal damage, further pointing to the nervous tissue as an important disease target.

Restricted access

Lucas Bouys and Jerome Bertherat

Described for the first time in 1985, Carney complex (CNC) is a rare dominantly inherited multiple neoplasia syndrome with almost full penetrance, and characterized by both endocrine – primary pigmented nodular adrenocortical disease with Cushing’s syndrome, acromegaly and thyroid tumors – and non-endocrine manifestations such as cardiac, cutaneous and mucosal myxomas, pigmented cutaneous lesions, psammomatous melanotic schwannoma, osteochondromyxoma and a wide range of other tumors with potential malignancy. The pathophysiology of CNC is a model of dysregulation of the cAMP-PKA signalling in human diseases: as described twenty years ago, inactivating heterozygous mutations of PRKAR1A formerly known as CNC1, encoding the regulatory subunit 1α of protein kinase A are identified in more than 70% of the index cases, while inactivating mutations of genes encoding phosphodiesterases are found in rare and particular forms of the complex. There is at present no medical specific treatment for CNC, every confirmed or suspected CNC patient should be managed by a multidisciplinary team according to each manifestation of the disease and offered a long-term follow-up and genetic counselling. The better knowledge that we have now of this fascinating rare disease and its genetics will help to improve patients outcome.

Restricted access

Kristina Laugesen, Leonie H.a. Broersen, Simon Bøggild Hansen, Olaf M Dekkers, Henrik Toft Sørensen, and Jens Otto L. Jorgensen

Glucocorticoids are, besides non-steroidal anti-inflammatory drugs, the most widely used anti-inflammatory medications. Prevalence studies indicate substantial use of both systemic and locally acting agents. A recognized adverse effect of glucocorticoid treatment is adrenal insufficiency, which is highly prevalent based on biochemical testing, but its clinical implications are poorly understood. Current evidence, including randomized trials and observational studies, indicates substantial variation among patients in both risk and course of glucocorticoid-induced adrenal insufficiency, but both are currently unpredictable. Oral and intra-articular formulations, as well as long-term and high-dose treatments, carry the highest risk of glucocorticoid-induced adrenal insufficiency defined by biochemical tests. However, no route of administration, treatment duration, or dose can be considered without risk. More research is needed to estimate the risk and temporal pattern of glucocorticoid-induced adrenal insufficiency, to investigate its clinical implications, and to identify predictors of risk and prognosis. Randomized trials are required to evaluate whether hydrocortisone replacement therapy mitigates risk and symptoms of glucocorticoid-induced adrenal insufficiency in patients discontinuing glucocorticoid treatment. This review aims to provide an overview of available evidence, pointing to knowledge gaps and unmet needs.

Restricted access

Kris Gustave Poppe

Severe thyroid dysfunction may lead to menstrual disorders and infertility via direct and indirect interactions with the hypothalamo-pituitary-ovarian axis and the reproductive organs. However, the precise prevalence of infertility in women with thyroid disorders remains unknown. Fertility problems may persist even after restoring normal thyroid function, and then surgery and/or an assisted reproductive technology (ART) may be necessary to obtain a pregnancy. The initial step in an ART treatment is the ovarian stimulation, putting strain on the thyroid gland, potentially leading to (permanent) hypothyroidism in women with thyroid autoimmunity (TAI) or when already treated with thyroid hormones (LT4). Moreover, women with ovarian and unexplained causes of infertility have a higher prevalence of TAI. In women treated with LT4, a serum TSH level <2.5 mIU/L should be targeted before ART.

In women with TSH levels >4.0 mIU/L, fertilisation rates, embryo quality and live birth rates may be impaired and improved with LT4 therapy. In euthyroid women with TAI, LT4 should not be given systematically, but on a case-by-case basis if serum TSH is >2.5 mIU/L.

For all of the above reasons, women of infertile couples should be screened routinely for the presence of thyroid disorders.

In this review, we will focus on the gaps in the current knowledge, the remaining questions on the associations between thyroid (disorders) and (assisted) reproduction and make proposals for future investigations that may lead to a better understanding and contribute to novel treatment options in the long term.

Free access

Juliette Harris, Arthur Gouhier, and Jacques Drouin

Pioneer transcription factors have key roles in development as master regulators of cell fate specification. Only a small fraction of all transcription factors have the pioneer ability that confers access to target genomic DNA sites embedded in so-called ‘closed’ heterochromatin. This ability to seek and bind target sites within the silenced portion of the epigenome is the basis for their role in changing cell fate. Upon binding heterochromatin sites, pioneer factors trigger remodeling of chromatin from a repressed into an active organization. This action is typically exerted at enhancer regulatory sequences, thus allowing activation of new gene subsets. During pituitary development, the only pioneer with a well-documented role is Pax7 that specifies the intermediate lobe melanotrope cell fate. In this review, a particular focus is placed on this Pax7 function but its properties are also considered within the general context of pioneer factor action. Given their potent activity to reprogram gene expression, it is not surprising that many pioneers are associated with tumor development. Overexpression or chromosomal translocations leading to the production of chimeric pioneers have been implicated in different cancers. We review here the current knowledge on the mechanism of pioneer factor action.

Open access

Marian Schini, Richard Jacques, Eleanor Oakes, Nicola Peel, Jennifer S Walsh, and Richard Eastell

Introduction

The least significant change (LSC) is a term used in individuals in order to evaluate whether one measurement has changed significantly from the previous one. It is widely used when assessing bone mineral density (BMD) scans. To the best of our knowledge, there no such estimate available in the literature for patients with disorders of calcium metabolism. Our aim was to provide an estimate of the least significant change for albumin-adjusted calcium in patients with normocalcaemic hyperparathyroidism (NPHPT) and primary hyperparathyroidism (PHPT).

Methods

We used the within-subject standard deviatio calculated in a population of NPHPT and PHPT patients and multiplied it by 2.77.

Results

The LSC for NPHPT and PHPT were found to be 0.25 and 0.24 mmol/L, respectively (1.00 and 0.96 mg/dL). In clinical practice, the value of 0.25 mmol/L could be used.

Discussion

The least significant change given, could be used in two ways in these patients. First, it gives a range to which values are expected. This can provide some reassurance for the patient and the physician in cases of intermittent hypercalcaemia. Moreover, it can be a marker of whether an individual has an actual significant change of his calcium after parathyroid surgery.

Restricted access

Eilon Krashin, Barbara Silverman, David M. Steinberg, Daniel Yekutieli, Shmuel Giveon, Offer Fabian, Aleck Hercbergs, Paul J. Davis, Martin Ellis, and Osnat Ashur-Fabian

Objective: The association between dysregulated thyroid hormone function and cancer risk is inconclusive, especially among different age groups and uncommon malignancies. We sought to determine the relation of TSH and free T4 levels with overall cancer risk as well as risk of specific cancer types.

Design and methods: Data on thyroid hormone profile was collected from 375,635 Israeli patients with no prior history of cancer. Cancer cases were identified via the Israel National Cancer Registry. Cox proportional hazards model was used to assess hazard ratios for overall cancer as well as twenty cancer subgroups.

Results: 23,808 cases of cancer were detected over median follow up of 10.9 years. Among patients younger than 50 at inclusion, TSH in the hyperthyroid range, elevated free T4 and subclinical hyperthyroidism were associated with increase cancer risk (HR 1.3, 1.28 and 1.31, respectively). In contrast, patients 50 or older with clinical hyperthyroidism were at lower cancer risk (HR 0.64). Elevated TSH was associated with decreased risk of prostate cancer (HR 0.67). Log TSH elevation was associated with decreased risk of thyroid cancer (HR 0.82) and increased risk of melanoma (HR 1.11) and uterine cancer (HR 1.27). Elevated free T4 was associated with increased lung cancer risk (HR 1.54), while free T4 levels above the normal range and clinical hyperthyroidism were related to lower colorectal cancer risk (HR 0.59 and 0.08, respectively).

Conclusions: Thyroid hormones display opposing effects on cancer risk, based on patient age and cancer type.

Restricted access

Nuria Valdés, Amit Tirosh, Meg Keil, Constantine A Stratakis, and Maya Lodish

Objective

Due to the rarity of Cushing’s syndrome (CS) in children and adolescents, data are scarce about BMI during active disease and following remission. Therefore, our aim was to analyze BMI after long-term remission and determine predictive factors for promptly identifying patients at risk of being overweight or obese after remission for CS.

Design

Retrospective cohort study.

Patients

73 patients: 58 (79.4%) had Cushing disease, 40 males (58%), median age of 12 years (IQR: 9–15). The mean follow-up time was 22.4 ± 18.2 months (range: 4–98).

Methods

Main outcome measures: BMI, lipid profile, blood pressure, HOMA-IR.

Results

At diagnosis, only eight (11%) patients had a normal weight. Although the BMI z-score at the last follow-up improved (2.0 ± 0.7 to 1.0 ± 1.2, P < 0.001), 44% remained overweight or obese after 2 years of remission according to the Kaplan-Meier curves. The BMI z-scores at the last follow-up correlated only with HOMA-IR levels (r: 0.49, P = 0.027). We found two independent factors related to reaching a normal weight: BMI z-score at diagnosis (HR: 0.156, 95% CI: 0.038–0.644; P = 0.01) and BMI z-score change at 6 ± 2 months (HR: 2.980, 95% CI:1.473–6.028; P = 0.002), which had high accuracy when a cut-off of 0.5 was used for ROC analysis (AUC = 0.828 (0.67–0.97); P < 0.001).

Conclusions

Children and adolescents with CS have a high risk of being overweight or obese after successful treatment for their disease. At risk patients can be identified quickly based on their baseline BMI and initial weight loss after surgery. Efforts should focus on adopting healthy diet and lifestyle in the immediate postoperative period.

Open access

Lina Schiffer, Alicia Bossey, Punith Kempegowda, Angela E Taylor, Ildem Akerman, Dagmar Scheel-Toellner, Karl-Heinz Storbeck, and Wiebke Arlt

Objective: Androgens are important modulators of immune cell function. The local generation of active androgens from circulating precursors is an important mediator of androgen action in peripheral target cells or tissues. We aimed to characterize the activation of classic and 11-oxygenated androgens in human peripheral blood mononuclear cells (PBMCs).

Methods: PBMCs were isolated from healthy male donors and incubated ex vivo with precursors and active androgens of the classic and 11-oxygenated androgen pathways. Steroids were quantified by liquid chromatography-tandem mass spectrometry. The expression of genes encoding steroid-metabolizing enzymes was assessed by quantitative PCR.

Results: PBMCs generated 8-fold higher amounts of the active 11-oxygenated androgen 11-ketotestosterone than the classic androgen testosterone from their respective precursors. We identified the enzyme AKR1C3 as the major reductive 17β-hydroxysteroid dehydrogenase in PBMCs responsible for both conversions and found that within the PBMC compartment natural killer cells are the major site of AKRC13 expression and activity. Steroid 5α-reductase type 1 catalyzed the 5α-reduction of classic but not 11-oxygenated androgens in PBMCs. Lag time prior to the separation of cellular components from whole blood increased serum 11-ketotestosterone concentrations in a time-dependent fashion, with significant increases detected from two hours after blood collection.

Conclusions: 11-oxygenated androgens are the preferred substrates for androgen activation by AKR1C3 in PBMCs, primarily conveyed by natural killer cell AKR1C3 activity, yielding 11-ketotestosterone the major active androgen in PBMCs. Androgen metabolism by PBMCs can affect the results of serum 11-ketotestosterone measurements, if samples are not separated in a timely fashion.