A common end-product of digested protein — phenylalanine — triggers hormones that make rodents feel less hungry and results in weight loss, consistent with a replacement study presented at the Society for Endocrinology annual conference in Brighton.
A better understanding of the mechanism by which protein diets cause weight loss could lead on to the event of medicine and diets that tackle the growing obesity epidemic.
Hormones drive our appetite by telling us once we are hungry, and once we are full. Ghrelin may be a hormone that tells us once we are hungry. In contrast, high levels of the hormone GLP-1 tell us once we have had enough food and tell our bodies to prevent eating. Understanding the mechanisms by which hormones affect our feeding patterns may help identify new ways of treating or preventing obesity. Previous studies have shown that protein-rich diets encourage weight loss by making people feel fuller, though these diets are difficult to stick to and therefore the mechanisms by which this happens is unknown.
In this study, researchers Mariana Norton and Amin Alamshah from Imperial College London ran variety of experiments on both mice and rats. within the first experiment, they gave 10 rats and mice one dose of phenylalanine, a chemical produced within the gut when our body breaks down protein-rich foods, like beef, fish, milk and eggs. within the second experiment, diet-induced obese mice, which are typically used as a model of human obesity, got phenylalanine repeatedly over seven days. Both experiments compared their results to an equivalent number of rodents that weren’t given phenylalanine.
The researchers found that the single-dose of phenylalanine reduced food intake, increased levels of GLP-1 and decreased levels of ghrelin. Repeated administration also caused weight loss within the obese mice. The researchers also observed that the rats were traveling more, which could encourage them to reduce .
To understand the mechanisms by which phenylalanine could be stimulating these hormones, the researchers administered a final experiment by studying gut cells during a Petri dish . They found that phenylalanine interacted with a receptor called the calcium sensing receptor (CaSR), which it had been CaSR successively causing levels of GLP-1 to extend and appetite to decrease.
“Our work is that the first to demonstrate that activating CaSR can suppress appetite,” said lead author of the study Mariana Norton. “It highlights the potential use of phenylalanine or other molecules which stimulate CaSR — like drugs or food components — to stop or treat obesity.”
According to Miss Norton, the precise mechanisms by which phenylalanine suppresses appetite and weight still got to be determined, and there are likely to be additional mechanisms which also are involved within the beneficial effects of a high protein diet.
The researcher’s next steps are going to be to determine whether phenylalanine can produce an equivalent effects in humans as in mice, and to further confirm the importance of CaSR in our response to protein-rich foods.
The study L- Phenylalanine modulates gut hormone release, and suppresses food intake in rodents via the Calcium Sensing Receptor are going to be presented by Miss Mariana Norton at the Society for Endocrinology BES 2016 Conference in Brighton.
The Society for Endocrinology BES 2016 Conference is held 7-9 November 2016 in Brighton, UK. The Conference brings together the simplest of basic science, translation research, clinical investigation and clinical practice.
The Society for Endocrinology may be a UK- based membership organisation representing a worldwide community of scientists, clinicians and nurses who work with hormones. Further information are often found at www.endocrinology.org