Endocrine Abstracts

High protein diets are highly satiating but hard to maintain. By understanding the mechanisms underlying these effects we may be able to identify new anti-obesity therapies. Protein is broken-down into amino acids in the gut which are detected by a series of nutrient sensors. The calcium sensing receptor (CaSR) is primarily activated by calcium ions, but is positively allosterically modulated by aromatic amino acids, especially L-phenylalanine. Sti...

High protein diets are highly satiating but hard to maintain. By understanding the mechanisms underlying these effects we may be able to identify new anti-obesity therapies. Protein is broken-down into amino acids in the gut which are detected by a series of nutrient sensors. The calcium sensing receptor (CaSR) is primarily activated by calcium ions, but is positively allosterically modulated by aromatic amino acids, especially L-phenylalanine. Sti...

Protein stimulates insulin release and improves post-prandial glycaemic excursions. The underlying mechanism has previously been attributed to gastric emptying, incretin release and direct pancreatic stimulation. However, our studies suggest the calcium sensing receptor (CaSR) in the vagus nerve plays an important role. The CaSR has a well characterised role in calcium homeostasis, but also acts as a protein metabolite sensor. In response to the amino acid products of protein ...

Introduction: The gut hormone peptide YY 3-36 (PYY3-36) is secreted postprandially from intestinal L-cells to signal satiety. Peripheral administration of PYY3-36 suppresses food intake in rodents and humans. PYY3-36-based drugs are therefore promising anti-obesity treatments. It has been proposed that circulating PYY3-36 supresses appetite via the Y2 receptor (Y2R) in the hypothalamic arcuate nucleus (ARC). The vagus nerve, the majo...

Background: Kisspeptin is a peptide product of the KiSS-1 gene and a key regulator of the hypothalamo-pituitary-gonadal axis. Pregnancy is associated with raised plasma kisspeptin concentrations. However, there is significant variation in the plasma kisspeptin levels quoted in previous studies. We investigated the effects of pre-analytical factors including processing time and anticoagulant type on plasma kisspeptin-immunoreactivity (IR) measurement.Meth...

High protein diets are effective at promoting weight loss and stimulating the secretion of pancreatic hormones. Understanding the mechanisms underlying these effects may highlight new potential therapeutic targets. The calcium sensing receptor (CaSR) is stimulated by calcium and plays a critical role in calcium homeostasis. However, it is also found in many tissues unrelated to calcium regulation. CaSR activity can be modulated by aromatic amino acids, most potently by ...

High protein diets suppress appetite, but are difficult to adhere to. Understanding how the gut senses protein may identify mechanisms to drive satiety. Amino acid products of protein digestion are thought to be sensed by G protein coupled receptors in the gut, including the calcium sensing receptor (CaSR). Calcium ions are the major ligand of the CaSR, but aromatic amino acids, particularly L-phenylalanine (L-Phe), allosterically modulate CaSR activity....

Background: Hypothalamic amenorrhoea (HA) accounts for over 30% of cases of amenorrhoea in women of reproductive age. Current treatments have limited success rates and side effects. We have recently shown that a single injection of the novel hormone kisspeptin potently stimulates reproductive hormone release in women with HA. However, twice-daily kisspeptin administration to women with HA, results in tachyphylaxis due to desensitisation of the kisspeptin receptor. This suggest...