CONTEXT: The myokine irisin may increase energy expenditure and affect metabolism. OBJECTIVE: The objective of the study was to elucidate predictors of irisin and study whether circulating irisin may have day-night rhythm in humans. DESIGN: This was an observational, cross-sectional study with an additional 24-hour prospective observational arm (day-night rhythm substudy) and two prospective interventional arms (mixed meal substudy and exercise substudy). SETTING: The study was conducted at the Hellenic Military School of Medicine (Thessaloniki, Greece). PATIENTS AND INTERVENTIONS: One hundred twenty-two healthy, young individuals were subjected to anthropometric and body composition measurements, and their eating and exercise behavior profiles were assessed with validated questionnaires. Subgroups were subjected to day-night rhythm, standardized meal ingestion, and 30-minute aerobic exercise studies. MAIN OUTCOME MEASURES: Circulating irisin levels were measured. RESULTS: Ιrisin levels were lower in males than females (P = .02) after adjustment for lean body mass, which was its major determinant. Irisin levels followed a day-night rhythm (P < .001) with peak at 9:00 pm. Irisin levels were increased at the end of exercise (84.1 ± 10.0 vs 105.8 ± 14.3 ng/mL; P < .001). Irisin levels were not affected by intake of a standardized meal and were not associated with caloric intake or diet quality. CONCLUSIONS: In healthy, young individuals, circulating irisin displays a day-night rhythm, is correlated with lean body mass, and increases acutely after exercise.
CONTEXT: The myokine irisin may increase energy expenditure and affect metabolism. OBJECTIVE: The objective of the study was to elucidate predictors of irisin and study whether circulating irisin may have day-night rhythm in humans. DESIGN: This was an observational, cross-sectional study with an additional 24-hour prospective observational arm (day-night rhythm substudy) and two prospective interventional arms (mixed meal substudy and exercise substudy). SETTING: The study was conducted at the Hellenic Military School of Medicine (Thessaloniki, Greece). PATIENTS AND INTERVENTIONS: One hundred twenty-two healthy, young individuals were subjected to anthropometric and body composition measurements, and their eating and exercise behavior profiles were assessed with validated questionnaires. Subgroups were subjected to day-night rhythm, standardized meal ingestion, and 30-minute aerobic exercise studies. MAIN OUTCOME MEASURES: Circulating irisin levels were measured. RESULTS: Ιrisin levels were lower in males than females (P = .02) after adjustment for lean body mass, which was its major determinant. Irisin levels followed a day-night rhythm (P < .001) with peak at 9:00 pm. Irisin levels were increased at the end of exercise (84.1 ± 10.0 vs 105.8 ± 14.3 ng/mL; P < .001). Irisin levels were not affected by intake of a standardized meal and were not associated with caloric intake or diet quality. CONCLUSIONS: In healthy, young individuals, circulating irisin displays a day-night rhythm, is correlated with lean body mass, and increases acutely after exercise.
Authors: Mathias Schlögl; Paolo Piaggi; Susanne B Votruba; Mary Walter; Jonathan Krakoff; Marie S Thearle Journal: Appetite Date: 2015-03-09 Impact factor: 3.868
Authors: T Ebert; S Kralisch; U Wurst; M Scholz; M Stumvoll; P Kovacs; M Fasshauer; A Tönjes Journal: Int J Obes (Lond) Date: 2015-08-19 Impact factor: 5.095
Authors: Paweł Jóźków; Dawid Koźlenia; Katarzyna Zawadzka; Marek Konefał; Paweł Chmura; Katarzyna Młynarska; Michał Kosowski; Marek Mędraś; Jan Chmura; Piotr Ponikowski; Jacek Daroszewski Journal: J Physiol Sci Date: 2018-05-14 Impact factor: 2.781