Endocrine Abstracts

PTH plays an important role in bone metabolism. Active acromegaly is associated with increased bone turnover. Reduction in bone turnover markers occurs following biochemical cure/control of acromegaly. We examined the effect of active acromegaly and its treatment on PTH concentration and PTH target-organ sensitivity.10 patients with active acromegaly (defined as GH nadir greater than 1mU/L following 75g oral glucose load and IGF1 above reference range) a...

Adult Growth Hormone Deficiency (AGHD) is associated with relative phosphate deficiency. Phosphate is an important determinant of serum PTH concentration. PTH target-organ sensitivity is reduced in AGHD and may underlie the pathogenesis of AGHD-related osteopaenia. We examined the effect of phosphate supplementation on change in PTH target-organ sensitivity when given simultaneously with Growth Hormone Replacement (GHR) in AGHD patients.24 AGHD patients ...

Background: Untreated adult growth hormone deficiency (AGHD) is associated with hypertension, obesity and hyperleptinemia. Leptin is linked to obesity related hypertension, is secreted in a circadian rhythm and may contribute to the regulation of BP circadian rhythmicity.Methods: We studied the relationship between plasma leptin (half hourly samples), ambulatory systolic BP (SBP), diastolic BP (DBP) and mean arterial pressure (MAP) over a 24-h period in ...

Relaxin-3 (INSL-7) is a recently discovered member of the insulin superfamily, a group of structurally related hormones whose precursors have a domain arrangement similar to that of pro-insulin. Relaxin-3 mRNA is expressed in the nucleus incertus of the brainstem which has projections to the hypothalamus, an area important in appetite regulation. Relaxin-3 binds with high affinity to the recently discovered previously orphan G-protein-coupled receptor, GPCR135, which is expres...

Glucocorticoid sensitivity is dependent on the intracellular concentration of the glucocorticoid receptor (GR). GR expression is regulated in a complex, cell-type specific manner, but in most cell types the GR is subject to negative autoregulation by glucocorticoid exposure. Many human diseases are associated with reduced tissue sensitivity to glucocorticoids, including inflammatory arthritis, asthma, and chronic obstructive pulmonary disease. Therefore there is interest in ap...

Leptin stimulates osteoblastic cell proliferation, differentiation and mineralisation and inhibits osteoclast generation; leptin secretion and bone turnover are altered in adult growth hormone deficiency, a condition associated with osteoporosis. The aim of this study was to investigate leptin circadian rhythm and its association with bone turnover in untreated AGHD and following growth hormone replacement (GHR).We sampled peripheral venous blood at half...

Adult Growth Hormone Deficiency (AGHD) is associated with osteoporosis. PTH circadian rhythmicity is important for bone remodelling. Abnormalities in PTH circadian rhythms, including a blunted nocturnal rise, have been reported in AGHD and may contribute to osteoporosis development. GH replacement (GHR) results in improvement of PTH circadian rhythmicity and bone mineral density (BMD). In health, increasing age is associated with declining GH secretion and the appropriateness ...

Alterations in PTH circadian rhythmicity have previously been reported in Adult Growth Hormone Deficiency (AGHD) and may contribute to the pathogenesis of AGHD-related osteoporosis. However, changes in PTH circadian rhythm have not been correlated with bone mineral density (BMD) in AGHD. Serum phosphate is a likely determinant of PTH rhythm. We examined the PTH and phosphate circadian rhythms in AGHD patients with reduced (defined as femoral neck T-score <-1.0) and normal B...

Growth hormone (GH) and leptin regulate body composition and leptin is elevated in adult growth hormone deficiency (AGHD), a syndrome characterised by increased adiposity. We have previously shown that GH replacement for 1 month reduces 24-h mean leptin concentration independent of changes in fat mass. The long tem effects of GHR on leptin have not been described.24-h mean total leptin concentration was measured using half-hourly blood sampling, to accou...

Some people with obesity have hormonal, metabolic and circulatory changes that constitute the metabolic syndrome that resemble characteristics of patients with Cushing's syndrome. A link between the two conditions, possibly genetic, has therefore been suspected, and the glucocorticoid receptor gene (GRL, 5q31-q32) has been one of the candidate genes.The single nucleotide polymorphism N363S is an ATT to GTT missense alteration within exon 2 of G...