Mitochondria and Health
Senescence is the hallmark of cellular aging. The senescent cells have stopped dividing. Cells accumulate mutations and structural damage with age. The damage is sensed and the cells are then taken out of the cell cycle by the tumor suppressor, p53, for autophagy and repairs or to undergo programmed cell death. In either case there is rejuvenation. There is, however, an intermediate scenario where, due to lack of the necessary resources, these cells become stuck in limbo. A brake is pulled on them and the cells shrivel due low growth or activity and fail to perform the normal biological function. They still occupy space and prevent the capable cells--stem or induced-stem--from dividing. They, however, begin to secrete inflammatory factors, instead. Coupled to the renegade shriveled state, inflammation causes further structural damage in tissues and organs of the body, leading to degeneration. The common obvious...