Researchers discover bone marrow may be the source of systemic aging
A new study published in the journal "Nature Aging" identifies a surprising factor in how the body ages: the bone marrow. Experiments on mice revealed that as blood-producing cells age, they generate immune cells that promote chronic inflammation, which in turn damages tissues throughout the body.
A new study published in the journal "Nature Aging" points to a surprising factor that may affect how the body ages: the bone marrow. In an experiment on mice, researchers discovered that as blood-producing cells age, they generate immune system cells that promote inflammation. These cells travel through the bloodstream and reach various parts of the body, potentially affecting muscles, lungs, and other vital functions.
Bone marrow acts as a factory, continuously producing blood and immune cells. Researchers questioned what happens when this "factory" itself ages. The study suggests that as we grow older, a low-grade, long-lasting inflammation develops in the body. This is not the acute inflammation felt during illness or injury, but a quiet, continuous process that damages tissues over time. The researchers investigated whether stem cells in the bone marrow participate in this process.
The study focused on a protein called SIRT3, which helps cells produce energy and cope with stress. Researchers found that as stem cells age, SIRT3 levels decline. To test the impact of this decline, they modified mouse stem cells to produce more SIRT3 and transplanted them into mice. The results were striking: mice receiving the improved cells produced fewer inflammation-promoting immune cells.
Compared to control groups, these mice showed greater physical strength, better memory, improved blood sugar regulation, and healthier lungs. The researchers then transferred immune cells derived from these improved stem cells to other mice, observing similar improvements in muscle function and overall health. Senior researcher Danica Chen from the University of California, Berkeley, stated: "The strongest evidence comes from our transplantation and cell transfer experiments."
In essence, the researchers identified a potential pathway: aging stem cells in the bone marrow produce more inflammatory immune cells, which then circulate and contribute to aging phenomena in other organs. It is important to emphasize that this study was conducted on mice, not humans, and does not prove that increasing SIRT3 levels extends human lifespan. "The first question is whether the mechanism we identified in mice is also preserved in humans," Chen noted.
This study challenges the traditional view that organs age independently. Instead, it suggests that one system can influence the rate of deterioration in others. While this remains a preliminary animal study, it points to an intriguing idea: to understand systemic aging, we must look deep inside the bones.
