Although their contribution to depression has not been assessed as extensively as that of BDNF, several reports have pointed to a role for additional growth factors in depressive disorders, including FGF-2, NGF, VEGF, and EPO (see Table 2), as well as macrophage migration inhibitory factor (MIF), which is considered as a pro-inflammatory cytokine that has neurogenic actions. Here, NGF is linked to depressive symptom measurement.