Senescent Cells and Antiaging Medicine: Selective Removal of Senescent Cells

Aging is a phenomenon that progresses with age, interrelated at the levels of cells, organs, and individuals. Cellular senescence is an old-known phenomenon [1], but in recent years, it has been reported that a large amount of inflammatory cytokines are secreted from senescent cells, adversely affecting surrounding cells and promoting cellular senescence, a “senescence-associated secretory phenomenon” (SASP). This has clarified the relationship between cellular senescence and organ aging/individual aging (Fig. 27.1). Using genetically modified mice, a model mouse that removes these senescent cells from the body was created. As a result, it was possible to suppress various symptoms associated with aging and extend lifespan [2], proving the concept of anti-aging treatment by removing senescent cells (senolysis), and various methods are being developed worldwide for senescent cell removal therapy. Senescent cells do not proliferate, but they have the characteristic of not leading to cell death, and they accumulate little by little in the body with aging. Therefore, as a treatment method, attempts are being made to selectively lead senescent cells to cell death (apoptosis). This section provides an overview of the removal of senescent cells by immunity.