BDNF and depressive disorder: One ofthe neurotrophins in the BDNF, which facilitates the growth and sustainability ofnerve cells, modulates synapse response and is responsible for synapseplasticity.24 A recent study showed thatfailure of synapse neuroplasticity (neurogenesis, axon branching, dendritogenesis,and synaptogenesis) in particular regions of the brain, especially the hippocampus,is the main pathophysiological factor in depression.