Seven Mayo Clinic studies in Nature journals map the diversity of senescent cells, trace why they fuel chronic inflammation and test early interventions in older mice; human benefit remains unproven.
Mayo Clinic scientists have reported seven studies, published in Nature journals, that examine senescent cells, often called "zombie" cells because they stop dividing yet remain metabolically active. These cells release inflammatory substances that are thought to contribute to diseases of ageing. According to Mayo Clinic, the work from its Robert and Arlene Kogod Center on Aging shows that senescent cells are far more varied than previously understood, with characteristics that differ by tissue and by the process that pushed them into senescence. The team also describes a gene-activity tool called SenMayo, tested on bone biopsies from older adults, that helps identify such cells more consistently across tissues.
Other papers in the series look at why these cells keep producing inflammatory signals. The researchers report that several of the mechanisms involve malfunctioning mitochondria, the structures that supply a cell's energy: mitochondrial DNA and RNA can trigger immune responses, and changes in mitochondrial metabolism can alter inflammatory gene activity through epigenetic effects. The authors suggest this could eventually allow scientists to block the harmful inflammatory signalling while leaving the cells themselves in place, an alternative to trying to destroy every senescent cell. The studies also feed into the NIH-funded Cellular Senescence Network (SenNet) Consortium, which aims to map senescent cells across the human body.
The team also tested ways to reduce the number or effect of senescent cells, including senolytic drugs, a natural compound found in tomatoes and genetic techniques aimed at specific cell populations. In older mice, depending on the approach, these interventions were associated with lower inflammation and improvements in physical frailty, brain inflammation and performance on cognitive tasks. Another study proposes IL-23R as a possible blood biomarker of biological ageing. Mayo Clinic stresses that the medical applications remain preliminary: the treatment results come from animal experiments, and further research is needed to establish whether any of these approaches is safe and effective in people.
