Session: OR09-Obesity: Physiologic Responses to Energy Balance Disruption
Room 307 (Moscone Center)
In a randomized cross over design, nine healthy subjects (age:23 ± 1yrs; BMI:23.6±0.7kg/m2) were studied in the laboratory with controlled energy expenditure and caloric consumption. Blood sampling was performed for 24-h following two nights of normal sleep (2300-0730) or partial sleep restriction (0100-0530). Samples taken at 60min intervals were assayed with liquid chromatography electrospray ionization-mass spectrometry (LC-ES-MS), for detection of 2-AG and 2-OG.
Both 2-AG and 2-OG display clear circadian rhythms with a nadir around mid sleep and peak levels in the early afternoon. Following sleep restriction, the amplitude of the rhythm is significantly increased for both lipids (2-AG: 151 ±24 vs 126 ±24pmol/ml, p = 0.01; 2-OG 894±120 vs 709±85pmol/ml, p = 0.005), due to an increase in peak levels (2-AG: 386 ±60 vs 335 ±61 pmol/ml, p = 0.008; 2-OG: 3329±284 pmol/ml vs 3138 ±255 pmol/ml, p = 0.08). Mean 24-h levels of 2-AG and 2-OG were highly correlated during the normal sleep condition (r = 0.80, p < 0.05) and during the restriction condition (r = 0.84, p < 0.05). Moreover, despite the two conditions being separated by at least one month, mean 24-h levels were highly correlated between the normal and restricted sleep sessions for both 2-AG (r = 0.98, p < 0.001) and 2-OG (r = 0.83, p = 0.005), indicating within-subject reproducibility.
This study provides the first demonstration of a robust circadian rhythm of human plasma EC levels and reveals that sleep restriction results in increased amplitude of the mid-sleep to early afternoon rise of both 2-AG and 2-OG. Elevation of peak daytime levels of EC may contribute to the risk of overeating associated with sleep deprivation.
Nothing to Disclose: ECH, KS, RL, ET, HD, CJH, EV
*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm
See more of: Abstracts - Orals, Featured Poster Presentations, and Posters