Handbook of Vitamin C Research

378Akihito Ishigamicontrols (12,13). The mean survival time of these SMP30 knockout mice was approximately6 months (Figure 2). On the other hand, wild type mice survived for approximately 24months. Although phenotypical analysis during the survival interval of SMP30 knockoutmice uncovered no obvious abnormalities, immediate postmortem examination revealedatrophy in almost all their abdominal organs. Thus, aging progressed by about four times thespeed in SMP30 knockout mice over that in the controls.Figure 1. SMP30 knockout and wild type mice. The SMP30 knockout mouse is born normal and isunchanged in any obvious way from the wild type mouse.Figure 2. Shortened life span of SMP30 knockout mice. Twenty male SMP30 knockout and twentymale wild type mice were used. SMP30 knockout mice displayed an increased mortality rate starting atabout 3 months of age compared to the cumulative survival rates for both strains.