Meeting Abstract
Hibernation is an ideal animal model to study diseases such as obesity and osteoporosis. Hibernators, marmots among them, are able to nearly double their body mass in fat stores and remain inactive for extended periods of time without exhibiting obesity or tissue atrophy. The endocannabinoid (EC) system is involved in modulating neural signaling, circadian rhythms, behavior, appetite, thermogenesis, as well as bone and energy metabolism. All of these systems are altered to maintain homeostasis during hibernation. This study aims to better understand the involvement of the EC system in the regulation of physiological processes during hibernation by quantifying EC and EC-like ligands for both active and hibernating marmots. We hypothesized that there would be significant changes in EC and EC-like ligand concentrations at the tissue level in marmots between active and hibernating states. Several EC and EC-like ligand concentrations were measured in brain, serum, brown adipose tissue, white adipose tissue, bone marrow, cortical bone and bone epiphyses using microflow chromatography coupled with tandem quadrupole mass spectrometry (LC-QQQ-MS). Significant findings included a 20-fold decrease in 2-arachidonoyl glycerol (2-AG) in cortical bone during hibernation, supporting our hypothesis and possibly suggest a peripherally controlled suppression in bone and energy metabolism.
