Endocrine Abstracts

Perfluorooctanesulfonate (PFOS) and its related product perfluorooctanic acid (PFOA) are anthropogenic fluorosurfactants widely used in consumer products. In general, studies in rodents have supported the conception that PFOS perturbs testis function, such as by inducing Sertoli cell injury. It remains to be demonstrated if similar effects could be reproduced in humans. We sought to examine its effects on human spermatogenesis by using a human Sertoli cell primary culture syst...

There is no consensus on the role of insulin secreted from pancreatic β-cells in regulating its own secretion, nether in rodent islets nor in human islets. We have now investigated whether there is an autocrine signalling role for insulin in human islets by determining insulin receptor expression and assessing the effects of insulin receptor activation using a non-peptidyl insulin-mimetic termed L-783,281. All experiments used hand-picked human islets of Langerhans. Human...

Previously we have demonstrated up-regulated expression of COX-2 and enhanced synthesis of PGE2 in cervical carcinomas. (Sales et al. 2001. J. Clin. Endocrinol Metab. 86(5):2243-2249). Enhanced PGE2 synthesis as a consequence of COX-2 overexpression has been associated with various carcinomas and is regarded as a promoter of neoplastic cell proliferation and angiogenesis. In sexually active women growth and invasiveness of neoplastic cervical cells may be...

Mice and rats are unusual amongst mammals for having 2 structurally similar but non-allelic insulin genes. Both genes are functional but their expression patterns relative to each other have not been conclusively determined. The insulin 1 gene (ins 1) has been shown in several studies to be selectively glucose responsive in mice and rats. We have used the MIN6 cell line to examine passage-related changes in ins 1 and 2 expression and to test glucose responsiveness of the 2 gen...

The FAD-dependent, mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH) is essential for the transport of reducing equivalents derived from glycolysis (or in sperm fructolysis) into the mitochondrial compartment for the synthesis of ATP. It has been shown that multiple (three) promoters of the mGPDH exist so that the expression is regulated in a tissue-restricted manner. Promoter A is expressed in brain, brown adipose tissue and pancreas, promoter B is ubiquitous and promo...

Background & Aims: An increased prevalence of obesity among patients with prolactinoma (PR) and weight loss after treatment (specially in male patients) has been reported1,2. On the other hand, weight gain after treatment has been observed in another study3. In this study we looked at the evolution of body weight in 37 patients with PR, 22 macroprolactinomas (MAPR) and 15 microprolactinomas (MIPR).Methods: We conducted a retrospective s...

Recently, two new peptides named Orexin-A and Orexin-B, have been implicated in the regulation of feeding behaviour. Studies in starved rats have shown that catabolic activity quickly predominates, reinforced by elevated corticosterone, not driven by ACTH, implicating adrenal activity as a metabolic regulator. In view of these findings, we sought to investigate whether orexin and orexin receptors are present in human fetal and adult adrenals, and therefore may be implicated in...

ACTH is a 39 amino acids polypeptide which stimulates adrenocortical steroid production. The N-terminal segment of ACTH(1–24) is biologically active and the C-terminal is considered to have greater antigenicity. In one previous (‘RoSA’) and one current (‘RADS2’) clinical trial synthetic ACTH (zinc tetracosactide; depot synacthen) was administered to autoimmune Addison’s disease (AAD) patients to stimulate adrenocortical regeneration. 4/13 RoSA pat...

An 89-year-old female family physician presented to an orthopaedic surgeon with a short history of aches and pains. She was suspected to have vitamin D deficiency and was empirically prescribed three intramuscular injections of 6 million units of cholecalciferol at monthly intervals. A few days after the third dose she presented with nausea, generalised weakness, confusion and ataxia. She appeared drowsy and dehydrated. Vital parameters were normal and there were no focal neur...

Background: Immune responses to self-peptides should not generally occur. However, four of 12 autoimmune Addison’s disease (AAD) patients developed adverse reactions immediately after synacthen injections, following repeated subcutaneous synacthen injections during a clinical trial (RoSA study). We wondered if these adverse effects were due to the production of anti-synacthen (ACTH1–24) antibodies.Methods: We evaluated the presence o...