BDNF and treatment resistant depression: We hypothesised that EPO would increase peripheral BDNF levels since EPO infusion, as previously mentioned, increases CNS BDNF in preclinical models, and in several human studies of patients with neurodegenerative and neuropsychiatric conditions EPO is also associated with neuroprotective and neuroproliferative potentials [16], including TRD and BD [21;22].