Exercise-induced normalization of decreased BDNF serum concentration in elderly women with remitted major depression

Major depression (MD) has been associated with decreased brain-derived neurotrophic factor (BDNF) serum levels, while antidepressant drugs were found to increase these decreased BDNF levels. We investigated if this is also caused by a single exercise session in elderly women with remitted MD. In our study 35 elderly women with a (partially) remitted depressive episode of unipolar depression according to DSM-IV criteria within the last year and 20 age-matched healthy female controls were included. Depression severity was assessed by HAMD. Serum levels of BDNF were measured by ELISA. Blood samples were taken during the rest period before beginning the exercise including spiroergometry, at the end of the exercise and after a 30-min recovery period. At baseline MD patients showed significantly decreased BDNF serum levels compared to healthy female controls. After a single 30-min exercise period, we found a significant increase of BDNF serum levels in MD patients towards values comparable with the baseline levels of the healthy controls, followed by a significant decrease after 30 min rest, while the healthy controls showed only a mild but non-significant increase. In conclusion, a single exercise session leads to a significant up-regulation and transient normalization of BDNF serum levels in elderly women with remitted MD. This mechanism may contribute to the beneficial therapeutic and relapse-preventing effects of physical activity on MD.