The gut hormone peptide YY regulates appetite

Area of Science:

• Neuroendocrinology
• Gastroenterology
• Appetite Regulation

Background:

• Peptide YY (PYY) is a gut hormone involved in appetite regulation.
• PYY exists in two forms: PYY(1-36) and PYY(3-36), with PYY(3-36) being more selective for the Y2 receptor (Y2R).
• The hypothalamic arcuate nucleus, crucial for appetite control, expresses Y2R on neuropeptide Y (NPY) neurons.

Purpose of the Study:

• To investigate the role of PYY(3-36) in regulating food intake.
• To determine the receptor subtype mediating the anorectic effects of PYY(3-36).
• To explore PYY(3-36) as a potential therapeutic target for appetite control.

Main Methods:

• Administration of PYY(3-36) peripherally and directly into the arcuate nucleus of rodents.
• Measurement of food intake and C-Fos immunoreactivity in the arcuate nucleus.
• Assessment of PYY(3-36) effects in Y2R null mice and human subjects via peripheral infusion.

Main Results:

• Peripheral and central administration of PYY(3-36) inhibited food intake in rodents.
• PYY(3-36) increased C-Fos immunoreactivity in the arcuate nucleus, indicating neuronal activation.
• Y2R null mice were resistant to PYY(3-36)'s anorectic effects, confirming Y2R mediation.
• Human studies showed PYY(3-36) significantly decreased appetite and reduced 24-hour food intake by 33%.

Conclusions:

• PYY(3-36) acts via the Y2 receptor in the arcuate nucleus to physiologically regulate food intake.
• Postprandial release of PYY(3-36) signals satiety from the gut to the brain.
• PYY(3-36) represents a promising target for managing appetite and food intake.