In humans and other multicellular organisms, cells multiply. This defining feature allows embryos to grow into adulthood, and enables the healing of the many bumps, bruises and scrapes along the way.
Certain factors can cause cells to abandon this characteristic and enter a zombie-like state known as senescence where they persist but no longer divide to make new cells. Our bodies can remove these senescent cells that tend to pile up as we age. The older we get, however, the less efficient our immune systems become at doing so.
“In addition to no longer growing and proliferating, the other hallmark of senescent cells is that they have this inflammatory program causing them to secrete inflammatory molecules,” said Peter Adams, Ph.D., director and professor of the Cancer Genome and Epigenetics Program at Sanford Burnham Prebys and senior and co-corresponding author of the study.
Cells “running” this inflammatory program are considered to exhibit the senescence-associated secretory phenotype (SASP). Too many cells with SASP secreting inflammatory molecules can contribute to chronic inflammation in the body. This pervasive inflammation—called “inflammaging”—has been linked to many age-related diseases.
Scientists at Sanford Burnham Prebys and collaborators across the country published findings in Nature Communications showing that the mitochondria powering our cells also control the ability of a DNA repair protein to suppress SASP, which may reduce or delay inflammaging.
The research team turned human cells senescent by exposing them to radiation and then used those cells to demonstrate that DNA fixer tumor protein p53 suppressed SASP and one of its triggering events, the formation of cytoplasmic chromatin fragments (CCF).
These fragments are bits of damaged DNA that have been spewed from the cells’ nuclei into the gel-like cytoplasm that occupies the space in the cell between the outer membrane and central nucleus. The presence of DNA where it does not belong can trigger the immune system and contribute to SASP.
The scientists validated their findings in mice by treating them with a drug developed by cancer researchers to activate p53 as a way of suppressing tumors. In aged mice, the drug did not reduce the number of senescent cells but instead reversed the cellular signature that marks age-associated SASP, potentially stopping the inflammatory pollution that can lead to inflammaging.
In addition, the investigators discovered that senescent cells suffer from dysfunction in the mitochondria, serving as cells’ primary source of energy. Stressed mitochondria can cause senescent cells to form CCF and dampen the expression of the gene carrying the blueprint for p53.
“Altogether, we’ve identified a cellular circuit capable of promoting DNA repair and genome integrity while suppressing the dangerous inflammatory feature of senescent cells that contribute to age-related diseases,” said Karl Miller, Ph.D., staff scientist in the Adams lab at Sanford Burnham Prebys and lead and co-corresponding author of the study.
“We also have shown that this pathway can be modified by existing drugs in cultured cells and mice, so it may be possible to one day design a treatment that targets p53 to promote healthier aging.”
More information: Karl N. Miller et al, p53 enhances DNA repair and suppresses cytoplasmic chromatin fragments and inflammation in senescent cells, Nature Communications (2025). DOI: 10.1038/s41467-025-57229-3
News
Your Voice May Reveal How Fast Your Brain Is Aging
Researchers have developed a machine-learning “speech clock” that estimates age from subtle patterns in how people speak and what they say. It is possible that people’s voices may contain certain signals of aging that [...]
Optogenetics Pioneers Win 2026 Nobel Prize in Physiology or Medicine
The 2026 Nobel Prize in Physiology or Medicine has been awarded to Peter Hegemann, Georg Nagel, and Karl Deisseroth for the development of optogenetics, a revolutionary technology that uses light to control individual neurons [...]
Molecular Manufacturing: The Future of Nanomedicine – From NanoappsMedical Inc.
This book explores the revolutionary potential of atomically precise manufacturing technologies to transform global healthcare, as well as practically every other sector across society. This forward-thinking volume examines how envisaged Factory@Home systems might enable the cost-effective [...]
What is ‘American Covid’ and how bad is it?
Cases of so-called ‘American Covid’ are on the rise in the UK. The strain is officially called XFG, or ‘Stratus’, and is the most common variant in North America, hence the name. It might soon [...]
Researcher at Russian plague laboratory dies of ‘unknown’ infection
Russian authorities have imposed "anti-epidemic measures" after a laboratory worker at an institute in Siberia dedicated to studying the plague and other infectious diseases died of a mysterious illness. The researcher, a 28-year-old female [...]
GHCE Concept
From the preface of the book Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artificial Intelligence, Edited by Frank Boehm: Since the publication of my first book (Nanomedical Device and Systems [...]
A Surprising Brain Signal Could Explain Why Eating Less Protein Extends Lifespan
A new paper suggests that limiting protein intake triggers a coordinated response throughout the body that may help explain how protein restriction affects healthy aging. Animals respond to protein restriction, or reduced protein in [...]
Back and shoulder surgery is often worse than useless
Millions of operations should be scrapped SIX IN TEN Britons have surgery at some point. So do lots of Americans, at a cost of perhaps $500bn a year, a third of all spending on [...]
Cocaine plays with mind, hijacks brain circuit, drives increasingly rigid and repetitive behavior
Researchers have found that cocaine hijacks brain circuit, which to drive increasingly rigid and repetitive behavior. The brain circuit that normally participates in selecting natural mouth and face movements, but which becomes disproportionately engaged [...]
Injectable nanodevices could provide effective treatment for drug-resistant glioblastoma
The brain cancer glioblastoma is one of the most aggressive and treatment-resistant cancers known to medicine, carrying a median survival of just 12-15 months, even with the best available care. Now, researchers at the [...]
New Treatment Cuts “Bad” Cholesterol in Half for a Full Year
A single infusion of an experimental CRISPR-Cas9 therapy was reported to safely lower LDL cholesterol by 52.5% and triglycerides by 47.8%, as measured 12 months after treatment. What if one infusion could keep cholesterol [...]
Too Much RNA Can Drain a Cell’s Energy, Scientists Discover
A virus may cripple a cell’s power supply simply by producing too much of a molecule the cell needs to survive. New research from the Texas A&M College of Veterinary Medicine and Biomedical Sciences [...]
West African scientists warn of weakening health systems and urge stronger outbreak detection
LOME, Togo (AP) — West African laboratory scientists called on governments Friday to strengthen capacity to detect disease outbreaks to avoid another major outbreak, saying health systems across the region are becoming weaker. Participants [...]
A Little-Known Protein Could Point to a New Way To Treat Alzheimer’s
A study suggests that increasing SORLA protein levels could help treat Alzheimer’s disease and other disorders involving tau protein. Increasing SORLA, a protein with a protective role in the brain, helped mice withstand damage [...]
Cancer’s Hidden Antioxidant Shield Helps It Escape the Immune System
Blocking an antioxidant protein that tumors use to suppress immune attacks improved cancer immunotherapy responses in mice. Cancer cells can release antioxidants that interfere with the immune cells trying to kill them. Researchers have [...]
Scientists Find a Berry Compound That Helps Muscle Cells Burn Fat
Pterostilbene, a compound found naturally in some foods, affects how skeletal muscles process fats by stabilizing a protein called PPARδ and increasing its signaling activity. Pterostilbene, a natural compound found in blueberries, grapes, and [...]
