Use of high-dose androgens is associated with reduced brain derived neurotrophic factor in male weightlifters

Introduction: Use of high-dose androgens causes drastic changes in hormonal milieu and is associated with adverse medical, psychological, and cognitive effects. Brain derived neurotrophic factor (BDNF), a member of the neurotrophin family of growth factors plays a critical role in neuroplasticity, with implications for cognitive function and mental health. The impact of long-term, high-dose androgen use on BDNF in a natural setting has not been investigated. This study examined the association between long-term androgen exposure and BDNF levels, and the links between BDNF, heavy resistance exercise, hormones, androgens and mental health. Methods: We measured serum levels of BDNF and sex steroid hormones in male weightlifters (N=141) with a history of current (n=59), past (n=29) or no (n=52) androgen use. All participants completed questionnaires assessing maximum strength and measures of anxiety and depression. Group differences in BDNF were tested using general linear models adjusting for age, and associations between BDNF and strength, anxiety and depression using Pearson’s or Kendall’s correlations. Results: Both current (mean: 44.1 ng/ml (SD:12.7)) and past (39.5 ng/ml (SD:13.9)) androgen users showed lower serum BDNF levels compared to non-using controls (51.5 (SD: 15.3), p<.001, ηp²=0.10). BDNF levels were negatively related to maximal strength, and with hormonal status in past androgen users, but no significant associations were found with measures of depression and anxiety. Conclusion: Lower circulating BDNF concentrations in current and past androgen users, suggest that high-dose androgen exposure triggers persistent changes in BDNF expression. Further studies are needed to verifythe relationship and its’ potential clinical implications.