Gastrointestinal targets to modulate satiety and food intake

Diets that contain a relatively high level of proteins are regarded an effective treatment for weight control. Particularly for the prevention of weight increase after a period of weight loss. So far, it is not known whether it makes a difference which specific proteins are used in these diets. This dissertation studies which proteins have the greatest effect on a feeling of hunger and food intake. It turns out that proteins from peas have the greatest effect. It also turned out that inhibition of the decomposition of this protein in the stomach even increases the effect. Obese men ate less after they had been administered pea protein directly in the intestines, than after they had eaten this protein. These results can contribute to new perspectives in the treatment of overweight and obesity

Peptide-YY is released by the intestinal cell line STC-1

Dietary modulation of the response of gut satiety hormones, which partly regulate food intake, provides a promising treatment for overweight and obesity. Gut-derived cell lines such as STC-1 are widely used to investigate these hormonal responses to nutrients. To date, no peptide-YY (PYY) secreting cell line has been identified. The aim of this study was to investigate whether STC-1 cells are able to secrete PYY and if so, whether dietary compounds can modulate PYY secretion. The effects of fatty acid types C4:0, C12:0, C14:0, C16:0, and C18:0 on PYY release were investigated by measuring PYY in the supernatant after 30, 60, 90, and 120 min of incubation, respectively, using RIA assays. The STC-1 cells were able to secrete PYY in a time-dependent manner. It was shown that after 30 min, C4:0, C12:0, C16:0, and C18:0 caused increased PYY levels compared to the control. At time points 60 and 90 min, C4:0 and C18:0 induced elevated PYY levels compared to the control. After 120 min, C4:0, C14:0, and C18:0 caused elevated levels compared to the control. We are the first to show that the STC-1 cells are also able to secrete PYY next to cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1). Addition of fatty acids resulted in increased levels of PYY, which is consistent with the literature describing human studies. We conclude that the STC-1 cell line provides an appropriate cell line for screening the effects of ingredients on the release of the satiety-related gut hormones CCK, GLP-1, and PYY

Release of satiety hormones in response to specific dietary proteins is different between human and murine small intestinal mucosa

BACKGROUND/AIM: High protein diets are the most effective to stimulate cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1) release; however, which proteins are the most potent is not known. Here, the effects of specific dietary proteins on intestinal CCK and GLP-1 release were examined. METHODS: Duodenal biopsies of 10 healthy male subjects and 10 male rats were taken and placed in an Ussing chamber system. The biopsies were exposed on the luminal side to buffer, egg protein, codfish protein, ovomucoid, pea protein, and wheat protein. After an exposure time of 2 h, samples were taken from the serosal side. RESULTS: Pea protein and wheat protein increased CCK and GLP-1 release in human duodenal tissue, while codfish protein only increased CCK release. No elevated levels of CCK and GLP-1 were found after exposure of rat tissue to different proteins. CONCLUSION: Pea and wheat protein are the most potent stimulators of CCK and GLP-1 release in human duodenal tissue, and may therefore be good dietary additives in weight management