Article

Physiological Evidence for the Involvement of Peptide YY in the Regulation of Energy Homeostasis in Humans*

Obesity and Diabetes Clinical Research Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, AZ 85016, USA.
Obesity (Impact Factor: 4.39). 10/2006; 14(9):1562-70. DOI: 10.1038/oby.2006.180
Source: PubMed

ABSTRACT To explore the potential role of the endogenous peptide YY (PYY) in the long-term regulation of body weight and energy homeostasis.
Fasting and postprandial plasma PYY concentrations were measured after an overnight fast and 30 to 180 minutes after a standardized meal in 29 (21 men/8 women) non-diabetic subjects, 16 of whom had a follow-up visit 10.8 +/- 1.4 months later. Ratings of hunger and satiety were collected using visual analog scales. Resting metabolic rate (RMR) (15-hour RMR) and respiratory quotient (RQ) were assessed using a respiratory chamber.
Fasting PYY concentrations were negatively correlated with various markers of adiposity and negatively associated with 15-hour RMR (r = -0.46, p = 0.01). Postprandial changes in PYY (area under the curve) were positively associated with postprandial changes in ratings of satiety (r = 0.47, p = 0.01). The maximal PYY concentrations achieved after the meal (peak PYY) were negatively associated with 24-hour RQ (r = -0.41, p = 0.03). Prospectively, the peak PYY concentrations were negatively associated with changes in body weight (r = -0.58, p = 0.01).
Our data indicate that the endogenous PYY may be involved in the long-term regulation of body weight. It seems that this long-term effect was not exclusively driven by the modulation of food intake but also by the control of energy expenditure and lipid metabolism.

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Available from: Pablo Enriori, Oct 14, 2014
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