ESPE Abstracts

Fertility and puberty onset are controlled within the brain by a neural network that drives the secretion of gonadotropin-releasing hormone (GnRH) from hypothalamic neuroendocrine neurons. During postnatal development, various permissive signals must be integrated for the initiation of sexual maturation but the molecular events that orchestrate the timely activation of the GnRH neurons remain a major unsolved biological mystery. Increasing evidences point out Micro-RNAs (miRNA...

Hypercalcaemic disorders in children may present with poor feeding, hypotonia, lethargy, dehydration, vomiting, polyuria, failure to thrive, seizures and hypertension. The causes of hypercalcaemia in children, which can be classified as parathyroid hormone (PTH)-dependent or PTH-independent, are similar to those occurring in adults except that primary hyperparathyroidism and malignancy which the most common causes in adults, and account for >90% of adult patients with hype...

Resistance to thyroid hormone mediated by defective TRβ (RTHβ) or TRα(RTHα).Separate genes (THRA, THRB) undergo alternate splicing, generating nuclear receptors (TRα1, TRβ1, TRβ2) with distinct tissue distributions, which mediate thyroid hormone action; the function of a non-hormone binding protein (α 2), derived from the THRA locus, is unknown.RTHβ a dominantl...

Introduction: Over-production of androgens is linked to prostate cancer (PCa) in men and polycystic ovary syndrome (PCOS) in women. CYP17A1 produces dehydroepiandrosterone (DHEA), the precursor for androgens, via its 17,20 lyase activity. CYP17A1 lyase activity is regulated by the amount of P450 reductase for electron transfer; the presence of cytochrome b5; and protein phosphorylation. High androgen levels were linked to the phosphorylation of CYP17A1 protein...

Background: Thyroid hormone disrupting chemicals (THDCs) which are present in the environment, food and everyday consumer products, interfere with thyroid hormone signaling, possibly by interacting with thyroid hormone receptors (THRs). This alters the thyroid hormone homeostasis and affects various functions regulated by the thyroid hormone e.g. macronutrient metabolism, cardiovascular function, and normal brain development. Therefore, there is a necessity for detection and m...

Background: Mutations in GH1 gene cause isolated growth hormone deficiency. Several disease-causing mutations from patients with IGHD have been reported. These mutations have been shown to (a) produce shorter isoforms of GH that does not bind to growth hormone receptor, (b) cause diminished secretion of GH or (c) result in misfolded GH protein. Large sequencing studies from the non-clinical population show several hundred genetic variations in GH1 gene. Role of common polymorp...

Congenital adrenal hyperplasia (CAH) is a common disorder of steroid production mainly caused by a mutated CYP21A2 gene, causing 21-hydroxylase deficiency (21OHD). CAH due to 21OHD requires lifelong mineralocorticoid (MC) and glucocorticoid (GC) therapy. But, from the location of the enzyme block in the steroid production and increase of adrenocorticotropic hormone (ACTH) which stimulates the melanocortin type 2 receptor (MC2R) in the adrenal, excessive adrenal androgen produc...

Background: The cytochrome P450 CYP17A1 plays a vital role in regulating adrenal androgen production. The 17,20 lyase activity of CYP17A1 is key for androgen regulation. The orteronel and galeterone are known to inhibit 17,20 lyase activity however the detailed mechanisms of the inhibition of CYP17A1 activities remain unknown. These inhibitors have been developed to treat the castration resistant prostate cancer (CRPC) but little is known about their effects on adrenal androge...

Cytochrome P450 oxidoreductase (POR) is the obligatory redox partner of steroid and drug-metabolizing cytochrome P450s located in the endoplasmic reticulum. Mutations in POR cause a broad range of disorders like congenital adrenal hyperplasia that may resemble bone malformations resembling Antley-Bixler syndrome. Genome sequencing studies have revealed the existence of a POR missense variant P228. We aimed to determine the detailed functional impact of POR variant P228L for it...

Background: A broad spectrum of human diseases, including abnormalities in steroidogenesis, are caused by mutations in the NADPH cytochrome P450 oxidoreductase (POR) (1-2). Cytochrome P450 proteins perform several reactions, including metabolism of steroids, drugs and other xenobiotics. Therefore, genetic variations in POR can impact many different metabolic pathways by changing the activities of cytochromes P450 (1). In 2004 the first human patients with defe...