The exercise-induced myokine irisin does not show an association with depressiveness, anxiety and perceived stress in obese women.

Irisin has recently been proposed to act as a myokine secreted from skeletal muscle following exercise and to exert several health-beneficial effects, although its role is far from being established. In contrast to the growing body of literature on the biological regulation and function of irisin, there is no evidence on potential associations with mental functions. Since physical activity has been reported to have favorable impact on mental functions, we investigated the association of irisin with depressiveness, perceived stress, and anxiety as well as eating disorder symptoms in obese women. We included 98 female obese inpatients (age: mean ± S.D. 43.9 ± 12.5 years; body mass index 49.2 ± 8.3 kg/m(2)) covering a broad spectrum of psychopathology. Depressiveness (PHQ-9), perceived stress (PSQ-20), anxiety (GAD-7), and eating disorder symptoms (EDI-2) were assessed psychometrically. Plasma irisin obtained at the same time was determined by ELISA. Irisin did not correlate with depressiveness (r = -0.03, P = 0.80), anxiety (r = 0.14, P = 0.17) and perceived stress (r = -0.14, P = 0.18) as well as eating disorder symptoms in general (r = -0.09, P = 0.39). No correlation of irisin was observed with any subscales of the PSQ-20 and EDI-2 (after Bonferroni correction). In conclusion, irisin is not associated with depressiveness, anxiety and perceived stress in female obese patients. These results do not support the assumption of irisin being involved in psychoendocrine pathways of the regulation of depression or other mental functions such as anxiety and perceived stress.