Given the prominent and evolutionarily conserved role of IGF-1-related signaling in lifespan regulation, we have recently examined the somatotropic axis in mice deficient in the Zmpste24 metalloproteinase, which present a strong progeroid phenotype and exhibit many features observed in HGPS patients [25]. The gene discussed is ZMPSTE24; the disease is Hutchinson-Gilford progeria syndrome.