SERPINF1 and major depressive disorder: Taken together, PEDF may mediate its effects through neurotrophic, antiangiogenic and/or immunological mechanisms, all of which are relevant to depression neurobiology.58 As these systems influence each other,4, 59, 60 it is likely that a complex interplay between them is responsible for the effects of PEDF in depression and the antidepressant response; however, further work is requilred to determine the precise mechanisms involved.