July 7th, 2026
The growth in number of senescent cells with age is an important mechanism of degenerative aging. Many studies in mice have demonstrated rapid rejuvenation and reversal of many different aspects of aging and age-related conditions via selective destruction of senescent cells in aged tissues. Here, researchers review what is known of the way in which the age-related expansion of the senescent state in cell populations impedes stem cell function in older individuals. Stem cells support tissues by generating a supply of daughter somatic cells to replace losses, as well as via signaling that is important to regenerative capacity. As stem cell activity declines so too does tissue function and health.
Several cellular settings have been identified where senescence induction seems to exclude stem cell activity, thereby suggesting a functional competition between the two processes. One such example are mesenchymal stem cells (MSCs) used in therapy. Many of the potentially beneficial MSC properties are attributed to their ability to grow as high-density monolayers known as MSC sheets, which however can rapidly acquire senescence features under sustained high-density conditions. Another case of functional competition between senescence and stemness relates to bone marrow mesenchymal stem cells (BMSCs) which constitute a lifelong reservoir for somatic cell generation, and are shown to be significantly useful in bone regenerative medicine. It has, however, been observed that BMSC osteogenic differentiation is inhibited by senescence, thereby limiting the BMSC regenerative potential.
