Clearing out the zombie cells that accumulate in the body may help extend life without harmful effects, findings of a new study suggest. Although the research was conducted on mice, the results may possibly lead to ways that can help reduce risks for age-related health problems in humans.
Study researcher Jan van Deursen, from the Mayo Clinic College of Medicine, and colleagues found that when they kill off senescent cells that accumulate in mice, the animals were much healthier and lived longer compared with their counterparts.
Senescent cells are normal cells that have stopped dividing after experiencing an unusual amount of stress. These cells produce chemicals that can harm nearby cells and cause chronic inflammation.
Steven Austad, from the University of Alabama in Birmingham, described senescent cells as zombie cells that have outlived their usefulness and are bad for the body.
Although the immune system regularly eliminates senescent cells, the process becomes less effective with age. This explains why older creatures have more of these cells than the younger ones. These cells may no longer divide, but they secrete chemicals that trigger inflammation known to be associated with age-related diseases.
"Senescent cells that accumulate with aging are largely bad, do bad things to your organs and tissues, and therefore shorten your life but also the healthy phase of your life," van Deursen said.
What Happens When Senescent Cells Are Removed
In the study published in the journal Nature on Wednesday, van Deursen and colleagues used a drug to clear senescent cells in normal mice.
They observed that injecting the drug extended the life spans of the animals by 17 to 35 percent. The animals also appeared healthier as removal of the cells reduced the deterioration of and reduced the fat in several organs including the heart and kidney
What's more is that the technique did not appear to have produced harmful effects on the mice. The animals did not seem to experience ill effects after losing their senescent cells.
Van Deursen explained that cellular senescence served as an emergency brake that damage cells use to stop dividing. Stopping the cellular division of these cells helps in cancer prevention, but experts believe that these cells are no longer necessary once the emergency brake has been pulled.
The study shows that clearing these cells do not cause adverse effects, at least on the animals used in the experiment.
Promising Anti-Aging Treatment
Based on these findings, the researchers said that the therapeutic removal of senescent cells could be an attractive approach to have extended healthy lifespan. Most prospective anti-aging treatments involve people taking a drug for decades, but periodically clearing senescent cells may temporarily turn back the clock and boost the health of aging people.
"The advantage of targeting senescent cells is that clearance of just 60 to 70 percent can have significant therapeutic effects," said study researcher Darren Baker, also from Mayo Clinic, who was optimistic about the possible implications of the research on humans.
"If translatable, because senescent cells do not proliferate rapidly, a drug could efficiently and quickly eliminate enough of them to have profound impacts on healthspan and lifespan."