You might recall research published last near on NRG-1 levels in naked mole-rats. Here is an update: "The typical naked mole rat lives 25 to 30 years, during which it shows little decline in activity, bone health, reproductive capacity and cognitive ability. ... Naked mole rats have the highest level of a growth factor called NRG-1 in the cerebellum. Its levels are sustained throughout their life, from development through adulthood. ... NRG-1 levels were monitored in naked mole rats at different ages ranging from a day to 26 years. The other six rodent species have maximum life spans of three to 19 years. The cerebellum coordinates movements and maintains bodily equilibrium. The research team hypothesized that long-lived species would maintain higher levels of NRG-1 in this region of the brain, with simultaneous healthy activity levels. Among each of the species, the longest-lived members exhibited the highest lifelong levels of NRG-1. The naked mole rat had the most robust and enduring supply. ... In both mice and in humans, NRG-1 levels go down with age ... The strong correlation between this protective brain factor and maximum life span highlights a new focus for aging research, further supporting earlier findings that it is not the amount of oxidative damage an organism encounters that determines species life span but rather that the protective mechanisms may be more important."