From the Guidelines
Peptides and hormones secreted in response to food intake include ghrelin, amylin, cholecystokinin, GIP, GLP-1, insulin, leptin, oxyntomodulin, pancreatic peptide, and PYY.
Key Hormones
- Ghrelin: stimulates food intake, levels reduced in obesity and insulin resistance 1
- Amylin: decreases food intake, suppresses glucagon secretion, regulates body weight, and increases energy expenditure, levels lower in T1D and do not respond to meal stimulus 1
- Cholecystokinin (CCK): decreases appetite, delays gastric emptying, and promotes satiety 1
- Glucagon-like peptide-1 (GLP-1): regulates body weight by diminishing appetite and delaying gastric emptying, key mediator for glucose homeostasis 1
- Insulin: regulates appetite and body weight via central nervous system interactions, levels reduced in T1D 1
- Leptin: decreases appetite, levels reduced in T1D 1
- Peptide YY (PYY): suppresses appetite, important for islet cell development and regeneration of pancreatic cells 1
Mechanisms of Action
- GLP-1 receptor agonists stimulate insulin secretion, inhibit glucagon secretion, and delay gastric emptying, leading to reduced food intake and weight loss 1
- GLP-1 receptors are localized to the arcuate nucleus, area postrema, and nucleus tractus solitarius, regulating energy intake and expenditure 1
- Ghrelin and GLP-1 have inverse relationships with BMI, with ghrelin levels reduced in obesity and GLP-1 levels increased in response to meal stimulus 1
From the Research
Peptides and Hormones Secreted in Response to Food Intake
The following peptides and hormones are secreted in response to food intake:
- Ghrelin: an orexigenic hormone that increases food intake and body weight 2, 3
- Glucagon-like peptide-1 (GLP-1): an anorexigenic hormone that inhibits appetite 2, 3, 4
- Oxyntomodulin: an anorexigenic hormone that inhibits appetite 2, 3, 4
- Peptide tyrosine tyrosine (PYY): an anorexigenic hormone that inhibits appetite 2, 3, 5, 4
- Cholecystokinin (CCK): an anorexigenic hormone that inhibits appetite 2, 3, 4
- Pancreatic polypeptides: anorexigenic hormones that inhibit appetite 2, 3
- Insulin: a hormone that relays information regarding long-term energy stores and reduces food intake 2
- Leptin: a hormone that relays information regarding long-term energy stores and reduces food intake 2
- Nesfatin-1: a peptide that regulates food intake 4
- Uroguanylin (UGN): a peptide that regulates food intake 4
Mechanisms of Action
These peptides and hormones act through various mechanisms, including:
- Binding to G-protein-coupled receptors on the luminal side of enteroendocrine cells 2
- Influencing the activity of the arcuate nucleus (ARC) neurons of the hypothalamus 2, 5
- Influencing the nucleus of the tractus solitarius (NTS) through the adjacent circumventricular organ 2
- Regulating the release of other hormones, such as insulin and leptin 2
Regulation of Food Intake
The regulation of food intake involves a complex interplay between the gut, brain, and adipose tissue, and is influenced by various peptides and hormones, including those listed above 2, 3, 4.