Endocrine Abstracts

Importance: The major factor contributing to the high incidence of osteoporosis in older women is the reduction in estrogen synthesis. Isoflavones have a similar structure to 17-β estradiol and can act as selective estrogen receptor modulators.Objective: To determine the safety and effect of soy isoflavones on bone during early menopause.Design: Parallel, double blind, study.Setting: Secondary care resea...

Recent genome-wide association studies (GWAS) implicate the CYP17A1 locus in human blood pressure regulation. This gene is important in steroidogenesis, regulating both glucocorticoid and androgen synthesis through catalysis of 17α-hydroxylation and 17,20 lyase reactions. We hypothesised that functional CYP17A1 polymorphisms linked to those identified by GWAS influence blood pressure levels. We therefore screened the entire CYP17A1 locus by dire...

Aim: Increasing left ventricular mass index (LVMI) is associated with a poor prognosis in patients with chronic kidney disease (CKD). Blockade of the mineralocorticoid receptor (MR) in CKD leads to improvement in proteinuria and LV mass. However, the MR can be activated by aldosterone, cortisol and deoxycorticosterone (DOC) and their relative contribution to adverse events in CKD is unclear. We aimed to assess the correlation between mineralocorticoid excretion and LVMI in pat...

Background: Adult growth hormone deficient (AGHD) is associated with reduced bone turnover and reduced bone mineral density (BMD): factors improved by growth hormone replacement (GHR). Obesity is associated with reduced bone turnover but increased BMD. We investigated the impact of body mass index on parathyroid hormone (PTH), phospho-calcium metabolism and bone turnover in AGHD patients before and after GHR.Study design: Of 31 AGHD patients (15 obese pa...

Multiple Endocrine Neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by the combined occurrence of tumours of the parathyroids, pancreas and pituitary. The MEN1 gene, which is located on chromosome 11q13 and encodes a 610 amino acid protein (menin), belongs to the class of tumour suppressors. To investigate the role of menin in tumour suppression, three different mouse models have been generated through targeted disruption of the Men1 gene. ...

Introduction: Adult growth hormone deficiency (AGHD) is associated with target organ insensitivity to parathyroid hormone (PTH) and abnormal PTH circadian rhythm. In aging women with established osteoporosis, GH and insulin like growth factor -1 (IGF-1) concentrations are low and administration of GH has been shown to increase bone turnover and bone mineral density (BMD), but the mechanisms remain unclear. Consequently we investigated the effects of declining GH and IGF-1 conc...

Up to 15% of unselected patients with hypertension have evidence of inappropriate aldosterone production, identified by a raised ratio of plasma aldosterone to renin (ARR), suggesting that altered regulation of aldosterone synthesis is a key intermediate phenotype in essential hypertension. We previously described an association between the -344C/T 5'UTR polymorphism in the CYP11B2 (aldosterone synthase) gene and hypertension with raised ARR; the same genetic variation associa...

Aldosterone is an important cardiovascular hormone. Around 15 % of hypertensives have alteration in aldosterone regulation, defined by a raised ratio of aldosterone to renin (ARR). Studies of CYP11B2, the aldosterone synthase gene, focus on a single nucleotide polymorphism in the 5'promotor region (-344 C/T). We have shown that the T allele is associated with increased urinary excretion and plasma levels of aldosterone and is more common amongst hypertensives with a raised ARR...

BACKGROUND: Adult Growth Hormone Deficiency (AGHD) is associated with reduced bone mineral density (BMD). PTH plays an important role in bone metabolism and reports have suggested target cell insensitivity to PTH as a contributor to the changes in bone turnover seen in AGHD. Although growth hormone replacement (GHR) increases BMD, the underlying mechanisms remain unclear.OBJECTIVES: To determine the effect of GHR on 24-hour PTH profiles, phosphocalcium ...

We investigated the association between vitamin D metabolites and incidence of lower body (pelvis and lower limb) overuse musculoskeletal and bone stress injury in 1637 men and 530 women (22.6 ± 7.5 years), undergoing 12 weeks initial military training. We measured serum 25-hydroxyvitamin D (25(OH)D) and 24,25-dihydroxyvitamin D (24,25(OH)2D) by high-performance liquid chromatography tandem mass spectrometry, and 1,25-dihydroxyvitamin D (1,25(OH)2D) by...