Endocrine Abstracts

Backround: Androgenic anabolic steroids (AAS) are reported to increase cardiovascular risk by causing adverse changes in lipid profiles, impaired glucose tolerance, hyperhomocystinaemia and hypertension. Recent studies have also suggested impaired vascular reactivity in this group.Aim: To assess cardiovascular risk factors and arterial stiffness in AAS using and non-steroid using male bodybuilders and to compare them with healthy controls.Methods: Studies were conducte...

Background: Cortisol availability to target tissues represents a complex interplay of synthesis, secretion, metabolism and excretion. A number of these processes are regulated by enzymes that are encoded by genes that are key candidates in determining the metabolic and cardiovascular phenotype in man. Measurement of a range of corticosteroid metabolites allows the activity of these enzymes to be inferred. We have studied the pattern of cortisol metabolite excretion in a large ...

Aldosterone synthase catalyses the synthesis of the mineralocorticoid aldosterone in the adrenal zona glomerulosa and is encoded by the CYP11B2 gene. Recent studies have shown that CYP11B2 is also expressed in the cardiovascular system. CYP11B2 expression in the adrenal gland is regulated by the renin-angiotensin system and potassium. However, little is known about its expression in other tissues. In this study, we have quantitated CYP11B2 expression in the cardiovascular syst...

Background: Although androgens are traditionally considered to be pro-atherogenic, there is increasing evidence to suggest an inverse relationship between testosterone and cardiovascular risk. Endothelial dysfunction is an early event in the process of atherogenesis and may occur as a result of vascular oxidative damage. In vivo, human monocytes release reactive oxygen intermediates as part of a normal immune response.Aim: This study assessed the contribution of testostero...

A male patient treated with a thiazolidenedione (TZD) PPAR gamma agonist for Type 2 diabetes had a dramatic worsening of his thyroid eye disease (TED), which had been stable and inactive for more then two years. Expansion of the orbital fat seemed to be the underlying cause and we have investigated the effects of a PPAR gamma agonist (and subsequently an antagonist) on the adipogenesis of preadipocytes from 10 different patients, representing several fat depots, including TED ...

The hypothalamic melanocortin 4 receptor, its endogenous agonist, alpha melanocyte stimulating hormone and the endogenous antagonist, Agouti related peptide (Agrp) regulate energy homeostasis. However, the physiological role of the hypothalamic melanocortin receptor, MC3-R and its agonist, gamma MSH are currently unknown. We have previously shown that the MC3/4 agonist, a-MSH has no effect on GnRH release from hypothalamic explants and does not influence plasma gonadotrophins ...

Plasma homocysteine is now regarded as a graded risk factor for vascular disease comparable to smoking, high cholesterol and raised blood pressure. In diabetes homocysteine values have correlated with microalbuminuria and are thought to contribute to vascular damage. Folic acid is an essential co-factor for homocysteine metabolism and folic acid supplementation has been shown to reduce plasma homocysteine by about 30%.In this study patients with Type II ...

Objectives: Aldosterone synthase catalyses the synthesis of aldosterone in the adrenal zona glomerulosa and is encoded by the CYP11B2 gene. Recent studies have shown that the CYP11B2 gene is also expressed in the rat central nervous system (CNS), particularly the cerebellum and hippocampus, suggesting local corticosteroid production. The renin-angiotensin system regulates the expression of the CYP11B2 gene in the adrenal cortex. However, little is k...

Introduction: MicroRNA (miRNA) has been shown to post-transcriptionally regulate physiological systems modulating blood pressure, including the adrenal biosynthesis of aldosterone. This raises the possibility that levels of specific miRNAs circulating in plasma might reflect these functional effects and have diagnostic value in the identification of hypertension and its various underlying causes. In a previous study, we measured plasma levels of miRNAs originating from the miR...

Background: A polymorphism within the CYP11B2 gene, characterised by a C/T substitution at position 344, the putative binding site for steroidogenic transcription factor1, has been shown to influence aldosterone excretion rate and blood pressure in essential hypertension.Aims: Assess the effect of contrasting genotype for the SF1 site on urinary and plasma steroid production during dietary manipulation of the renin-angiotensin system and assess the press...