BDNF and major depressive disorder: Chronic stress that leads to a depression-like phenotype is also associated with reduced hippocampal BDNF levels.112–114 This effect was normalized by antidepressants,112,115 which also rescue stress hormone-triggered impairments in spatial memory.116 Therefore, in addition to the powerful antioxidant properties of hyperforin in H. triquetrifolium, we propose that its NMDA antagonist action prevents BDNF downregulation and improves depression- and anxiety-like behaviors.