Signal Transduction, Ageing and Disease.

Ageing is defined by the loss of functional reserve over time, leading to a decreased tissue homeostasis and increased age-related pathology. The accumulation of damage including DNA damage contributes to driving cell signaling pathways that, in turn, can drive different cell fates, including senescence and apoptosis, as well as mitochondrial dysfunction and inflammation. In addition, the accumulation of cell autonomous damage with time also drives ageing through non-cell autonomous pathways by modulation of signaling pathways. Interestingly, genetic and pharmacologic analysis of factors able to modulate lifespan and healthspan in model organisms and even humans have identified several key signaling pathways including IGF-1, NF-κB, FOXO3, mTOR, Nrf-2 and sirtuins. This review will discuss the roles of several of these key signaling pathways, in particular NF-κB and Nrf2, in modulating ageing and age-related diseases.