Pardo, MaríaCrujeiras, Ana BAmil, MaríaAgüera, ZaidaJiménez-Murcia, SusanaBaños, RosaBotella, CristinaTorre, Rafael de laEstivill, XavierFagundo, Ana BFernández-Real, José MFernández-García, José CFruhbeck, GemaGómez-Ambrosi, JavierRodríguez, RoserTinahones, Francisco JFernández-Aranda, FernandoCasanueva, Felipe F2015-03-162015-03-162014-04-22Pardo M, Crujeiras AB, Amil M, Agüera Z, Jiménez-Murcia S, Baños R, et al. Association of irisin with fat mass, resting energy expenditure, and daily activity in conditions of extreme body mass index. Int J Endocrinol; 2014:8572701687-8337http://hdl.handle.net/10668/1846Journal Article;FNDC5/irisin has been recently postulated as beneficial in the treatment of obesity and diabetes because it is induced in muscle by exercise, increasing energy expenditure. However, recent reports have shown that WAT also secretes irisin and that circulating irisin is elevated in obese subjects. The aim of this study was to evaluate irisin levels in conditions of extreme BMI and its correlation with basal metabolism and daily activity. The study involved 145 female patients, including 96 with extreme BMIs (30 anorexic (AN) and 66 obese (OB)) and 49 healthy normal weight (NW). The plasma irisin levels were significantly elevated in the OB patients compared with the AN and NW patients. Irisin also correlated positively with body weight, BMI, and fat mass. The OB patients exhibited the highest REE and higher daily physical activity compared with the AN patients but lower activity compared with the NW patients. The irisin levels were inversely correlated with daily physical activity and directly correlated with REE. Fat mass contributed to most of the variability of the irisin plasma levels independently of the other studied parameters. Conclusion. Irisin levels are influenced by energy expenditure independently of daily physical activity but fat mass is the main contributing factor.enFibronectinasGhrelinaÍndice de masa corporalActividad motoraTrastornos de las proteínas sanguíneasMetabolismo energéticoAnorexia nerviosaObesidadMedical Subject Headings::Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Globulins::Serum Globulins::FibronectinsMedical Subject Headings::Chemicals and Drugs::Hormones, Hormone Substitutes, and Hormone Antagonists::Hormones::Peptide Hormones::GhrelinMedical Subject Headings::Health Care::Environment and Public Health::Public Health::Epidemiologic Measurements::Biometry::Anthropometry::Body Mass IndexMedical Subject Headings::Psychiatry and Psychology::Behavior and Behavior Mechanisms::Behavior::Motor ActivityMedical Subject Headings::Diseases::Hemic and Lymphatic Diseases::Hematologic Diseases::Blood Protein DisordersMedical Subject Headings::Phenomena and Processes::Metabolic Phenomena::Metabolism::Energy MetabolismMedical Subject Headings::Check Tags::FemaleMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Psychiatry and Psychology::Mental Disorders::Eating Disorders::Anorexia NervosaMedical Subject Headings::Diseases::Nutritional and Metabolic Diseases::Nutrition Disorders::Overnutrition::Obesityresearch article24864142open access10.1155/2014/8572701687-8345PMC4016898