Representative schematic of neurotrophic signaling pathway in the Rheb(S16H)-transduced hippocampus. Rheb(S16H) transduction of hippocampal neurons causes the induction of neurotrophic factors such as BDNF and GDNF. Increases in those factors stimulates astroglial activation, resulting in additional GDNF production. The induction of neurotrophic factors in both neurons and astrocytes contributes to neuroprotection in the adult hippocampus.