Zombies are the stuff of legend, living dead that, depending on which movie you watch, are coming for everyone. We all have “zombie” cells in our bodies that make their presence known as we age. Zombie cells have become a popular way to describe something called cellular senescence because these cells act much like the zombies of our nightmares.
What are Zombie Cells?
Senescent cells have stopped dividing and are waiting to be removed from our body by the immune system. These cells are useful when we are young. They allow our body to put the brakes on cells that are either not working properly, are potentially cancerous, have finished a specific job (like scar formation as part of the healing process), or have reached the end of their useful life.
Senescent cells get their zombie name tag because they remain in our body in a state of suspended animation, secreting chemical messages that alert our immune system they need to be removed. When we are young, our immune system handles this job like a boss, but it falters as we age, maybe because it’s getting tired or because the increasing numbers of these cells start to overwhelm it.
Effects of Zombie Cells
As senescent cells start to build up, the chemical messages they are secreting cause negative effects on the cells around them. The chemical messages trigger inflammation, and these zombie cells may be the reason we see the increasing levels of inflammation that occur with older age.
Ongoing low-grade inflammation triggers processes that can lead to disease. Laboratory studies show even a few senescent cells can accelerate aging, or at least the symptoms of aging, like cancer and other diseases. Even the more aesthetic side effects of aging, including the graying of hair, worsening vision, and skin wrinkles, have been linked to cellular senescence.
Laboratory research also suggests that a high senescent cell burden is the reason older individuals react so severely to COVID-19, and that treatment with fisetin, a natural senolytic, may improve immune response to COVID. This insight is now the subject of a clinical trial by the Mayo Clinic to see if the improved response can be replicated in humans.
Treatment for Zombie Cells
Once researchers realized having senescent cells in our body is not particularly good for us and that we have increasing levels of them as we age, they started looking for ways to remove them. Luckily for us, it turns out that killing zombie cells may be easier than knocking off those zombies of the horror story kind.
Scientists have found some simple strategies to limit the number of these cells in our body. These strategies include: regular exercise; a regular program of fasting—missing breakfast from time to time is good, missing breakfast and lunch occasionally is even better; maintaining a healthy weight (fat tissue seems to be a magnet for senescent cells); and taking cellular health supplements such as senolytic complex.
These actions can work together to help you keep your inner zombie at bay and may help reduce the risk associated with high levels of senescent cells in your body, especially as you age.