Mature brain-derived neurotrophic factor (BDNF) is the major player of total BDNF in serum regarding prediction of antidepressant treatment outcome.

Abstract

Brain-derived neurotrophic factor (BDNF) is involved in neuroplasticity and pathophysiology of major depression (Hashimoto, 2010). SerumBDNF levels are decreased inmajor depression and tend to normalize under antidepressant treatment (Bocchio-Chiavetto et al. 2010). Moreover, baseline serum BDNF levels as well as its early rise have been found predictive to antidepressant treatment outcome (Mikoteit et al. 2014; Giese et al. 2014). BDNF is initially synthesized as precursor protein proBDNF, and mature BDNF (mBDNF) is derived by proteolytic cleavage. Only mBDNF exerts neurotrophic activity, while proBDNF has opposing functions. Remarkably, in most clinical studies, the unspecific BDNF enzyme-linked immunosorbent assay (ELISA) kits applied did not distinguish between proand mBDNF (BocchioChiavetto et al. 2010). Therefore, our aim was to explore if a specific ELISA kit for mBDNF (Human BDNF ELISA SK00752-1, Aviscera Bioscience, Santa Clara, CA, USA) in serum would be superior to the assessment of total serum BDNF, by using an unspecific antibody recognizing both proand mBDNF (BDNF Emax ImmunoAssay Systems, Promega, Switzerland), in predicting treatment response in major depression.