There are entire industries centered around ways to turn back the hands of time. From youthful night creams to miracle foods and elixirs that offer the promise to keep you young well into your golden years, there is no shortage of procedures and products that you can pay an arm and a leg for, all while on your quest for eternal youth. Up until recently, the aging of the cells in the human body has been a constant fact, an inescapable reality, and a tumultuous reminder that you’re just not 20 anymore.
The physical signs of aging are visible on the face as evidence that you squinted that one time or laughed so hard you left permanent lines on the sides of your mouth. The other signs—backaches from the simple act of moving a couch, feeling tired without that second cup of joe, and forgetting your cell phone when it’s in your hand—are arguably worse than seeing your reflection resemble your parent’s face more than the one in your baby pictures.
There have been countless efforts done in the world of science to help slow the crippling pace of time when it comes to aging, and in terms of stem cell research, some new studies have shown that they may just be the key to finding that elusive fountain of youth.
What are stem cells?
Each cell has its job to do to keep the body running properly, whether it be the white blood cells for the immune system or the mast cells, which are designed to let the body know when that shellfish it just ate wasn’t on the up and up. But behind every specialized cell doing what it’s made to do is a stem cell. The stem cell is the main player in the production of new cells to either replace those that have been destroyed or create new ones as needed. It has both the ability to influence the production of specialized cells (like the aforementioned white blood cells and mast cells) by either dividing continuously to produce new cells or playing shapeshifter and turning into the specialized cells the body so desperately needs.
Stem cells are split into three main groups; embryonic, adult, and induced pluripotent. The embryonic stem cells are designed to help with the growth of an embryo. They divide in the body to help create new cells in a bid to create new life. Adult stem cells have a few restrictions on how they can multiply inside the body. They are still able to replace and grow new cells, but can only do so for some cells in the body. For example, a blood stem cell can only create new blood cells and skin stem cells can only create new skin cells.
The third group, the induced pluripotent stem cells, are essentially created outside of the body. These “unnaturally occurring” cells are created in labs by extracting existing adult cells, tinkering with them a bit, thus reprogramming them to become a different type of stem cell entirely. This editing of the cells allows them to become any other type of cell that already exists within the realm of possibility.
Biological immortality
The only real truth in life is death. It’s unavoidable, and the clock runs out on everybody, eventually. The thing with some stem cells is that the universal truth of inevitable demise might not be as factual as once thought. Embryonic stem cells don’t have a biological clock—even though they are a part of yours. Their way of life is to create, create, create. They don’t age, they don’t die, and they don’t stop multiplying. The embryonic stem cells are a jack-of-all-tissue-trades in the sense that they can turn themselves into whatever the growing embryo needs when it needs it. During their tenure, they have the swift ability to disengage with the absorption of damaged proteins. They do this by using the proteasome.
The proteasome system is the main source of disposal on the cellular level throughout the body. This system has the incredible ability to mark proteins for certain death if they become damaged to the point of no return and send them packing. The out-with-the-old approach of the proteasome system is the main driver in the healthy function of the body.
In some animals, it’s speculated that because they can revert to the time when most cells of their body would be embryonic, they can avoid senescence altogether. One such animal—the turritopsis dohrnii jellyfish—can reverse their life cycle all the way back to the earliest stages if they sense a threat to their existence.
Is aging an inevitable disease?
One brazen study published in the US National Library of Medicine upheaves the common acceptance that aging is a fact of life. The researchers even go so far as to say that aging isn’t an inevitable of life but a disease that can be fought against with the right tools. But is it a miracle breakthrough in the world of health science or hogwash to market new products to the masses?
Aging occurs because of several things. The first is cellular production. As the body grows into its adulthood, cells are continuously created and repaired in record time. As the body reaches a certain age, those cells begin to slow down. This halt of new cell creation is what some believe leads to cellular damage—the main cause of aging. After time and too much cellular damage, the aging human body takes a hit and loses its ability to heal, becomes more susceptible to disease, and becomes frailer when injured, all of which ultimately leads to death. It’s hard to take a good record of the effect that aging has on everyone because, sure, everyone gets older eventually, but there are discrepancies in how fast aging hits, how healthy older people are, and whether or not someone will come down with a debilitating disease long before their time is up. Two seemingly similar 70-year-olds can experience the aging process in totally different ways in both body and mind.
Environmental factors have also been shown to play a huge role in the aging process. Things like stress levels, affluence, and even ethnicity have all been shown to play a role in how ‘quickly’ someone ages as opposed to their societal counterparts. It’s been said that the healthy behaviors practiced throughout early life have a great effect on how aging takes its eventual toll, but some things are thrown up to chance. In the case of things like Alzheimer’s disease, it doesn’t discriminate based on socioeconomic factors.
The use of stem cells to halt aging
Throughout the evolutionary process, humans and other mammals have lost regenerative abilities that are still seen today in animals lower on the food chain. This loss has led to the unavoidable aging process most humans dread. This is where the use of stem cells in the rejuvenation and disease-avoidance in humans came from. The firsts to explore the use of stem cells in this capacity were researchers James Till, Ernest McCullough, and Lou Siminovitch back in 1963. Through their studies, they found that the use of stem cells from the bone marrow of mice could lead to hematopoiesis (formation of new blood cells). This led to the startling discovery that stem cells could actually save those who were in grave condition. These findings paved the way to new research that has recently found a way to reverse aging in old cells by using an induced pluripotent form of embryonic stem cells.
The new research published in Nature Communications showed that when the aging cells were injected with the embryonic cells, the signs of aging disappeared and they were essentially restored to their more youthful state. It’s not just the cells that are doing all the work, though. In the study, the cells were given doses of a certain type of protein called Yamanaka protein (named after Nobel prize winner Shinya Yamanaka). When those proteins were combined with the adult stem cells, they were able to once again divide and multiply into the specialized cells that were needed, essentially traveling back in time to live their best life.
To take their study even further, they decided to shorten the time the cells were exposed to the proteins to see if they could reverse the clock by just a little bit. What they discovered was that they could reverse the age of the cells by as much or as little as they wanted to. This ability to halt the aging in the cells also led to the findings that it wasn’t just cell age they were affecting, it was overall function. Metabolism and waste removal were back to their tip-top shape and inflammation levels were lowered. The method was also used to help elderly mice regain youthful muscle gains.
Although the study is not definitive in the sense that it can stop the hands of time to avoid the grim reaper that awaits everyone at the other side of aging, it shows great promise in slowing the process and also healing any age-related declines in terms of diseases and the quality loss of life that often occurs with senescence.
Sources:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6057778/
https://www.who.int/news-room/fact-sheets/detail/ageing-and-health
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1369281/
https://www.yourgenome.org/facts/what-is-a-stem-cell
https://www.sciencedaily.com/releases/2018/03/180307101033.htm
https://www.science.org.au/curious/earth-environment/animals-can-live-forever
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