Senescence

Senescence is the process by which cells lose their ability to divide and function properly, often as a response to stress or damage. While this can initially be protective—preventing damaged cells from turning into cancer—it becomes a problem when too many senescent cells accumulate in the body. These "zombie cells" don't die off like they should but instead linger, releasing inflammatory signals that can harm surrounding tissues. Over time, this contributes to aging and age-related diseases.

Senescence can occur at the level of cells, tissues, or the entire organism.

- At the cellular level, senescence involves cells that have permanently stopped dividing but remain metabolically active, often contributing to aging and age-related diseases.

- At the organismal level, senescence manifests as a decline in physical and functional abilities, increased vulnerability to diseases, and reduced regenerative capacity.

Origin

Derived from the Latin word "senescere", which means "to grow old" or "to become aged." "Sen-": Root referring to old age (e.g., seen in words like "senior"). "-escere": A suffix that implies a process or transition. The term senescence was first used in English in the early 17th century, typically in biological or philosophical contexts to describe the aging process.