CX3CL1 and schizophrenia: Intriguingly, infusion of exogenous FKN into the hippocampus increases SGZ neurogenesis in aged rats (Bachstetter et al., 2011) and rescues neurogenesis and hippocampal-dependent memory deficits in the BDNFMet/Met mouse model of schizophrenia (Wang et al., 2014), implicating FKN's role in the activation and/or differentiation of NPCs.