title: Association of irisin with fat mass, resting energy expenditure, and daily activity in conditions of extreme body mass index.
abstract: 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.
authors.affiliation: Laboratory of Molecular and Cellular Endocrinology, Health Research Institute of Santiago (IDIS), University Hospital of Santiago (XXIS/SERGAS) and Santiago de Compostela University (USC), 15706 Santiago de Compostela, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Obesidómica Group, Laboratory 3, Health Research Institute of Santiago (IDIS), University Hospital of Santiago (XXIS/SERGAS), 15706 Santiago de Compostela, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Pardo
authors.affiliation: Laboratory of Molecular and Cellular Endocrinology, Health Research Institute of Santiago (IDIS), University Hospital of Santiago (XXIS/SERGAS) and Santiago de Compostela University (USC), 15706 Santiago de Compostela, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), 08908 Barcelona, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Crujeiras
authors.affiliation: Laboratory of Molecular and Cellular Endocrinology, Health Research Institute of Santiago (IDIS), University Hospital of Santiago (XXIS/SERGAS) and Santiago de Compostela University (USC), 15706 Santiago de Compostela, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Amil
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, 08907 Barcelona, Spain.
authors.forename: Zaida
authors.initials: Z
authors.lastname: Aguera
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, 08907 Barcelona, Spain ; Department of Clinical Sciences, School of Medicine, University of Barcelona, 08007 Barcelona, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Jiménez-Murcia
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Psychological, Personality, Evaluation and Treatment of the University of Valencia, 46010 Valencia, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Baños
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Basic Psychology, Clinic and Psychobiology of the Jaume I University, Castelló, 12071 Castelló de la Plana, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Botella
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Human Pharmacology and Clinical Neurosciences Research Group, Neuroscience Research Program, Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: de la Torre
authors.affiliation: Center for Genomic Regulation (CRG), 08003 Barcelona, Spain ; Centro de Investigación Biomédica en Red en Epidemiología y Salud Pública (CIBERESP), 08036 Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Estivill
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, 08907 Barcelona, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Fagundo
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdlBGi),Hospital Dr Josep Trueta, Girona, Spain.
authors.forename: Jose M
authors.initials: JM
authors.lastname: Fernández-Real
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Diabetes, Endocrinology and Nutrition, Hospital Cliínico Universitario Virgen de Victoria, 29010 Maálaga, Spain.
authors.forename: José C
authors.initials: JC
authors.lastname: Fernández-García
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Endocrinology and Nutrition, University Clinic de Navarra, University of Navarra, 31008 Pamplona, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Fruhbeck
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Endocrinology and Nutrition, University Clinic de Navarra, University of Navarra, 31008 Pamplona, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Gómez-Ambrosi
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdlBGi),Hospital Dr Josep Trueta, Girona, Spain.
authors.forename: Roser
authors.initials: R
authors.lastname: Rodríguez
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Diabetes, Endocrinology and Nutrition, Hospital Cliínico Universitario Virgen de Victoria, 29010 Maálaga, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Tinahones
authors.affiliation: CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain ; Department of Psychiatry, University Hospital of Bellvitge-IDIBELL, 08907 Barcelona, Spain ; Department of Clinical Sciences, School of Medicine, University of Barcelona, 08007 Barcelona, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Fernández-Aranda
authors.affiliation: Laboratory of Molecular and Cellular Endocrinology, Health Research Institute of Santiago (IDIS), University Hospital of Santiago (XXIS/SERGAS) and Santiago de Compostela University (USC), 15706 Santiago de Compostela, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), 15706 Santiago de Compostela, Spain.
authors.forename: Felipe F
authors.initials: FF
authors.lastname: Casanueva