Some anti-aging scientists consider the slowing down and eventual death of cells to be an unavoidable consequence of the aging process.
But other anti-aging scientists believe they’re on track to uncover new ways to deal with aging cells, sometimes called “zombie” cells, that include everything from getting rid of them to rejuvenating them.
What they’re discovering could one day help you slow the aging process and feel younger and healthier through middle age and beyond.
A large portion of the dust in your home, and other places for that matter, is made up of dead skin cells. But this is hardly surprising, since the average person sheds roughly 1,000 skin cells per hour.
In fact, all the cells that make up your skin are exchanged for new, fresh cells, every month. Even your internal organs get renewed on a cellular level – for example, the cells in your liver are switched out for new ones every year.
That’s because most of the cells in your body are pre-programmed to die after a certain period of time. This natural cell death is called apoptosis. When you’re young, these dead cells are removed from your body. In other words, as cells lose their function, they get expelled.
But as you age, the story changes. Once you hit 50, the ability of cells to multiply and renew slows down considerably. Your old cells still die, but instead of getting removed, they just hang around, unable to function. This zombie-like stage of dead cells is called senescence, and many scientists believe it’s this systemic breakdown that’s the main process behind cellular aging.
Deactivating Senescent Cells
Some researchers, including Barcelona-based biotech company Senolytx, are working on new ways to deactivate senescent cells.
This is important because senescent cells appear to cause harm to other tissues they come in contact with—just like being touched by a zombie would be bad for you (or at least that’s what happens on TV)!
So, as these damaged cells collect in the body, they appear to secrete inflammatory toxins that jumpstart the aging process and then inhibit other cells from performing their vital functions.
Getting rid of senescent cells, or at least reducing their levels, has already proven successful at reversing disease and reviving damaged tissues in experimental animal studies.
Using Stem Cells
While Senolytx is focusing on dealing with senescence directly, other companies are taking another approach to solving the problem before it happens, by using stem cells.
U.S. company AgeX Therapeutics is focused on research using pluripotent stem cells, which can technically divide without end. The company describes the process as simply replacing old parts with new ones, similar to the way you’d keep a car running on the road by switching out engine parts.
The goal of the AgeX research is to take stem cells and turn them into specific types of cells, engineered to replace cells that have died naturally or have been lost to disease.
They’ve already had some success using this method to replace brown fat tissue. Brown fat is considered “good fat” because it burns more energy to fuel your body and help balance blood sugar, and it’s often lost because of aging, obesity, and illness, such as Type-2 diabetes.
Targeting Senescent Cells to Clear them Away
Still another approach in dealing with harmful senescent cells comes from Rejuversen, a Swiss company. They are among the anti-aging research firms that have a different theory of aging– that it’s not systemic but instead involves a series of isolated biological conditions and events.
They’re attempting to prevent senescent cells from staying hidden from the immune system, a phenomenon that occurs more in older people than younger people. What researchers are trying to determine is what exactly is going on when immune cells don’t destroy senescent cells. Could it be similar to cancer, where these cells express a “don’t destroy me” signal so they can evade destruction? The answer isn’t clear.
But what most of these researchers do agree on is that if the immune system could better recognize senescent cells, it could more effectively clear them out of the body. In fact, natural killer (NK) cells naturally target senescent cells for elimination. They also produce compounds called cytokines that activate macrophage immune cells to gobble up senescent cells.
Studies suggest that transplanted macrophages can, in theory, gobble up senescent cells. Once again using cancer as a comparison, this is similar to the way many immunotherapies work, by bolstering the immune system to kill cancer cells. Researchers are investigating whether senescent cells can be taken out in similar ways.
For instance, researchers at the University of California San Francisco (UCSF) are already testing one immune approach. They’ve developed a patent-pending method to selectively clear senescent cells by stimulating an immune response. The researchers write, “Stimulating the immune system to clear these cells is unprecedented in the field and offers a new therapeutic modality to treat senescence associated conditions.”
While the UCSF researchers have only tested their approach in the laboratory, they’re preparing for clinical study.
What You Can do Today…
It’s interesting to consider the different methods under investigation to stop the aging process and which one—or several—will come out on top.
Time and more research will undoubtedly answer this question, but in the meantime, what can you do on your own to stop senescence?
One important thing is to keep your immune system at the top of its game so it’s better able to clear out senescent cells. This means eating a whole-food diet rich in vegetables, fruit and lean meats, exercising, getting plenty of sleep, and keeping stress at bay.
Another way is to “recruit” more brown fat. While research into brown fat is only just beginning, some studies suggest that you might be able to turn white fat brown by cooling your body regularly.
For example, in a review of brown fat published in the journal Diabetes, researchers suggested that only two hours of daily exposure to temperatures around 66 F could change white fat into brown fat.
- “A Scientific Answer to the Question: ‘Is Dust Mostly Skin?’ by Matthew Hart, Aug 18 2020.
- “Can Anti-Aging Research Keep Us Healthy in the Long Run?” By Jonathan Smith for Labiotech.eu, 11.30.2020. https://www.labiotech.eu/in-depth/anti-aging-cancer-cell-therapy/
- “AgeX Therapeutics Publishes Data in Peer-Reviewed Journal to Advance Potential Cell Therapy AgeX-
BAT1 for Type II Diabetes and Obesity.” By AgeXinc.
- “How can we live longer? 5 European startups extending our lifespans.” By Maricel Sanchez, December 30, 2019. https://www.eu-startups.com/2019/12/want-to-live-longer-5-european-startups-extending-our-
- “Senolytx Therapeutics and How they Are Tackling Senescent Cells: Simple BioTech Podcast #1.” Interview with Chief Scientific Officer of Senolytx Therapeutics, Tim Cash.
- “Senescence at a glance.” By Jeff S. Pawlikowski, et al. J Cell Sci. 2013 Sep 15; 126(18): 4061–4067.
- Antonangeli F, Zingoni A, Soriani A, Santoni A (2019). “Senescent cells: Living or dying is a matter of NK cells”. Journal of Leukocyte Biology . 105 (6): 1275–1283. doi:10.1002/JLB.MR0718-299R . PMID 30811627 .