Facultad de Ciencias de la Salud, Universidad de Zaragoza, 50009 Zaragoza, Spain; Instituto de Investigacion Sanitaria Aragon, 50009 Zaragoza, Spain. Instituto de Investigacion Sanitaria Aragon, 50009 Zaragoza, Spain; Adipocyte and Fat Biology Laboratory (AdipoFat), Instituto Aragonés de Ciencias de la Salud (IACS), 50009 Zaragoza, Spain. Department of Physiology, University of Kentucky, 40536 Lexington, KY, USA. Department of Physiology, University of Kentucky, 40536 Lexington, KY, USA; Sanders Brown Center on Aging, University of Kentucky, 40536 Lexington, KY, USA. Instituto de Investigacion Sanitaria Aragon, 50009 Zaragoza, Spain; Adipocyte and Fat Biology Laboratory (AdipoFat), Instituto Aragonés de Ciencias de la Salud (IACS), 50009 Zaragoza, Spain; CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III (ISCIII), 28029 Madrid, Spain. Electronic address: jmarbones.iacs@aragon.es.