title: A Lower Olfactory Capacity Is Related to Higher Circulating Concentrations of Endocannabinoid 2-Arachidonoylglycerol and Higher Body Mass Index in Women.
abstract: The endocannabinoid (eCB) system can promote food intake by increasing odor detection in mice. The eCB system is over-active in human obesity. Our aim is to measure circulating eCB concentrations and olfactory capacity in a human sample that includes people with obesity and explore the possible interaction between olfaction, obesity and the eCB system. The study sample was made up of 161 females with five groups of body mass index sub-categories ranging from under-weight to morbidly obese. We assessed olfactory capacity with the "Sniffin´Sticks" test, which measures olfactory threshold-discrimination-identification (TDI) capacity. We measured plasma concentrations of the eCBs 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine or anandamide (AEA), and several eCB-related compounds, 2-acylglycerols and N-acylethanolamines. 2-AG and other 2-acylglycerols fasting plasma circulating plasma concentrations were higher in obese and morbidly obese subjects. AEA and other N-acylethanolamine circulating concentrations were lower in under-weight subjects. Olfactory TDI scores were lower in obese and morbidly obese subjects. Lower TDI scores were independently associated with higher 2-AG fasting plasma circulating concentrations, higher %body fat, and higher body mass index, after controlling for age, smoking, menstruation, and use of contraceptives. Our results show that obese subjects have a lower olfactory capacity than non-obese ones and that elevated fasting plasma circulating 2-AG concentrations in obesity are linked to a lower olfactory capacity. In agreement with previous studies we show that eCBs AEA and 2-AG, and their respective congeners have a distinct profile in relation to body mass index. The present report is the first study in humans in which olfactory capacity and circulating eCB concentrations have been measured in the same subjects.
authors: Integrative Pharmacology and Systems Neuroscience Research Group, Neuroscience Research Program, IMIM (Hospital de Mar Medical Research Institute), Barcelona, Spain.|Department of Pharmacology, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Antoni
authors: A
authors: Pastor
authors: Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Fernando
authors: F
authors: Fernández-Aranda
authors: Cardiovascular Risk and Nutrition Research Group, Inflammatory and Cardiovascular Disorders Research Program, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Montserrat
authors: M
authors: Fitó
authors: Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain.|Department of Clinical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Susana
authors: S
authors: Jiménez-Murcia
authors: Department of Basic Psychology, Clinic and Psychobiology, University Jaume I, Castelló, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Cristina
authors: C
authors: Botella
authors: Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdlBGi), Hospital Dr Josep Trueta, Girona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Jose M
authors: JM
authors: Fernández-Real
authors: Department of Endocrinology and Nutrition, Clínica Universidad de Navarra, University of Navarra, IdiSNA, Pamplona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Gema
authors: G
authors: Frühbeck
authors: Department of Diabetes, Endocrinology and Nutrition, Hospital Clínico Universitario Virgen de Victoria, Málaga, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Francisco J
authors: FJ
authors: Tinahones
authors: Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain.
authors: Ana B
authors: AB
authors: Fagundo
authors: Integrative Pharmacology and Systems Neuroscience Research Group, Neuroscience Research Program, IMIM (Hospital de Mar Medical Research Institute), Barcelona, Spain.
authors: Joan
authors: J
authors: Rodriguez
authors: Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, Barcelona, Spain.
authors: Zaida
authors: Z
authors: Agüera
authors: Integrative Pharmacology and Systems Neuroscience Research Group, Neuroscience Research Program, IMIM (Hospital de Mar Medical Research Institute), Barcelona, Spain.|Department of Statistics and Operations Research, Universitat Politècnica de Catalunya, Barcelona, Spain.
authors: Klaus
authors: K
authors: Langohr
authors: Endocrine Division, Complejo Hospitalario U. de Santiago, Santiago de Compostela University, Santiago de Compostela, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.
authors: Felipe F
authors: FF
authors: Casanueva
authors: Integrative Pharmacology and Systems Neuroscience Research Group, Neuroscience Research Program, IMIM (Hospital de Mar Medical Research Institute), Barcelona, Spain.|CIBER Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto Salud Carlos III, Madrid, Spain.|Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain.
authors: Rafael
authors: R
authors: de la Torre
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001095:Arachidonic Acids / Q000097:blood*; D015992:Body Mass Index; D004435:Eating; D063388:Endocannabinoids / Q000097:blood*; D005260:Female; D005989:Glycerides / Q000097:blood*; D006801:Humans; D051379:Mice; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000503:physiopathology*; D055696:Olfactory Perception
chemical_list: D001095:Arachidonic Acids; D063388:Endocannabinoids; D005989:Glycerides; C094503:glyceryl 2-arachidonate