AQP4 and major depressive disorder: In addition to that, more recent studies have evidenced a role of AQP-4 as mediator of AD efficacy (Kong et al., 2009) and as a “protective” factor against corticosterone-induced depressive-like phenotype accompanied by an astrocytic pathology (Kong et al., 2014), proposing AQP-4 as a novel putative molecule affected in the etiopathogenesis of MDD.