ESPE Abstracts

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...

Androgens play a pivotal role in the pathophysiology of Polycystic Ovary Syndrome (PCOS), a common endocrine disorder affecting adolescent girls. Elevated androgen levels are implicated in the development and progression of PCOS, leading to symptoms such as hirsutism, acne, and irregular menstrual cycles. In patients with PCOS, the inhibition of androgen synthesis presents a therapeutic challenge. Given its crucial role in androgen production, CYP17A1 has become a major target...

Steroidogenic enzyme expression in the fetal adrenal and the placenta hints at the production and metabolism of adrenal-derived 11-oxy androgens (11OxyAs) in the fetal-placental unit. Thus, 11OxyAs are present in placental tissue, fetal cord blood and neonatal serum, and could have a particular role during fetal development. The metabolism of the 11OxyAs in the fetal unit, therefore, presents as a focal point of investigation. Adrenal androgens are primarily metabolized by the...

Objective: Adrenal cortisol production occurs through a biosynthetic pathway which depends on NADH and NADPH for energy supply. The mitochondrial respiratory chain and the reactive oxygen species (ROS) detoxification system are therefore important for steroidogenesis. Mitochondrial dysfunction leading to oxidative stress has been implicated in the pathogenesis of several adrenal conditions. Nonetheless, only very few patients with variants in one gene of the R...

A broad spectrum of human diseases, including abnormalities in steroidogenesis, are caused by mutations in the NADPH cytochrome P450 oxidoreductase (POR) (1-4). Human POR is a diflavin reductase that transfers electrons from NADPH to small molecules, non-P450 redox partners and cytochrome P450 proteins in the endoplasmic reticulum. Cytochrome P450 proteins perform a very wide range of reactions, including metabolism of steroids, drugs and other xenobiotics. Therefore, genetic ...

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...

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...