Cell Cycle Aging

Cell cycle aging refers to age-related alterations in the regulation of cell division, growth arrest, and cellular renewal. In young tissues, the cell cycle is tightly controlled to ensure balanced proliferation, differentiation, and repair. With aging, cell cycle control mechanisms become dysregulated due to accumulated DNA damage, telomere shortening, and altered checkpoint signaling. Many cells enter permanent growth arrest states such as cellular senescence to prevent propagation of damaged genomes. While this protects against cancer, it also reduces regenerative capacity and contributes to tissue degeneration. Declining cell cycle activity affects high-turnover tissues such as skin, blood, and the gastrointestinal tract. Cell cycle aging reflects a shift from proliferation toward damage containment, influencing both aging and disease risk. Understanding cell cycle aging is essential for balancing tissue regeneration with cancer prevention during aging.