BDNF and Mental deterioration: Intracellular signaling pathways of the BDNF/TrkB system, such as the PLCγ, PI3K/Akt and MAPK cascades, are also known to be modulated by glucocorticoids, leading to altered activation of downstream effectors involved in structural and functional plasticity in AD-relevant brain regions and cognitive decline, one of the most common pathologies of AD (Numakawa et al., 2009, 2017).