Endocrine Abstracts

Acetylation of DNA can result in gene silencing. In the thyroid such phenomena can lead to the loss of ability to accumulate radioiodide. The aim of this study was to examine the effects on the rat thyroid cell line FRTL-5 and human thyroid follicular cancer cell line FTC-133 of Trichostatin A (TSA), a histone deactylase inhibitor. A concentration of TSA was selected using MTT cell viability assays for use in uptake, efflux and expression studies. Cells were incubated with TSA...

Testosterone is the hormone that turns males into men and a lack of testosterone, whether of primary or secondary origin, causes hypogonadism characterized by lack of pubertal development or loss of maleness. It was generally assumed that in a man with a normal androgen receptor (AR) androgenicity is regulated by testosterone serum concentrations, slightly modified by SHBG. Only recently it became evident that variations in the AR gene influence testosterone action. Modulation...

Epigenetic phenomena such as methylation or acetylation of DNA can result in transcriptional inactivation and gene silencing. In the thyroid such phenomena can bring about the loss of ability to accumulate iodide as a result of methylation of CpG islands in human sodium iodide symporter (NIS) and Pendrin (PDS) DNA, limiting the ability to utilise radioiodide therapy. This study examines the effects of Trichostatin A (TSA) a histone deacetylase (HDAC) inhibitor on a rat thyroid...

Radioimmunoassay of steroid hormones is widely used but in application to clinical samples the technique can give erroneous results. In the diagnosis of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency raised plasma levels of 17-hydroxyprogesterone (17-OHP) are supportive evidence for the disorder. In the immunoassay of 17-OHP there are particular difficulties with the assay of plasma from neonates due to interference from steroids such as 17-hydroxypregne...

Uptake of ingested iodide (I-) in the thyroid is achieved through an active transport system, the sodium iodide symporter (NIS). The gland has the ability to accumulate I- from the bloodstream by a factor of 20-40. Seaweeds, which in vivo bear the same relationship to seawater, as does the thyroid to the bloodstream, have a dramatically more efficient I- uptake system, accumulating I- from seawater by a factor of anything up to 1 mil...

29-year old woman was admitted with tetany & severe hypocalcaemia despite treatment with high dose alpha-calcidiol (6 micrograms/day) and Calcium (8.0 g/day).PMH: Six years previously she had subtotal thyroidectomy for non-toxic goitre in another Department. Postoperatively she required Thyroxine, but was lost to formal endocrine follow-up. Five years later she presented with abdominal discomfort and occasional diarrhoea. Investigations performed by ...

A 59-year-old lady presented with 2 days of increasing confusion, hallucinations and drowsiness. Her family reported lethargy, weight gain and changing appearance over several months.On examination she was profoundly hypothyroid with typical coarsened facial features and dry skin. She had pulsus paradoxus, BP 120/70mmHg and Glasgow coma scale was 11/15. She was transferred to our care.Free thyroxine was <3.0pmol/L and TSH 30.8mu...

Congenital adrenal hyperplasia(CAH) and other disorders of adrenal steroid synthesis compromise synthesis of cortisol and aldosterone. Deficiency of 7-dehydrocholesterol-7-ene-reductase (DHCR7) in the Smith Lemli Opitz syndrome (SLOS) also affects cholesterol synthesis. New-born infants have dysmorphic facial features, microcephaly, second and third toe syndactyly and genital malformations. Later there is mental retardation and problems with cardiac and intestinal function thr...

PCOS is associated with increased biochemical risk markers for cardiovascular disease, particularly low HDL cholesterol and increased triglycerides. There is accelerated progression to type 2 diabetes and hypertension in middle age. These biochemical abnormalities associate with insulin resistance which is present to a greater extent than can be explained by obesity alone. Notwithstanding, hard endpoint data in terms of increased cardiovascular mortality remains elusive. Infla...

Orexins (A & B) are derived from a common 130 amino acid precursor peptide, prepro-orexin, by proteolytic cleavage, and orchestrate their actions by binding and activating two types of G-protein coupled receptors, orexin-1 receptor (OX1R) and orexin-2 receptor (OX2R). The OX1R preferentially binds orexin-A, whilst OX2R binds both orexin-A and ?B, with similar affinity. Besides playing a role in the regulation of feeding and energy homeostasis, orexins appear to increase se...