Could you imagine going to the hospital with a heart attack or cancer, and the doctor injects you with a chemical that instantly rejuvenates you as if you never had the disease? Or a dermatologist makes your wrinkles and sagging skin return to their youthful vigor to the time you were 20 with a simple injection? Well, stay tuned because scientists just got a step closer to these possibilities.
Scientists have found a way of rejuvenating middle-aged tissues in mice, which gives hope to the possibility of medical treatments for age reversal.
US researchers treated healthy mice with a unique type of gene therapy to make their cells more youthful. According to biological features that measure the effects of aging, they were successful.
If these new research results can be shown to fight specific health issues, “it would constitute a new therapeutic approach with a significant impact on unmet medical needs at all stages of our life,” said Heinrich Jasper, director at the US biotech firm Genentech.
The researchers used previous Nobel laureate Shinya Yamanaka’s studies, who revealed that a combination of four molecules Oct4, Sox2, Klf4, and cMyc – better known as Yamanaka factors – can turn adult cells into youthful stem cells capable of forming almost any tissue in the body.
The US researchers published their results in the Journal “Nature Aging,” disclosing that the middle-aged mice were given Yamanaka factors for several months. It rejuvenated them in numerous ways, from their skin to their kidneys.
The experiments revealed that age reversal was more effective when the Yamanaka factors were given to the mice for an extended period (7 to 10 months). Also, the therapy only worked on the mice between 12 and 15 months old (equivalent to age 35 – 50 in humans). When applied to the older mice comparable to 80-year-old humans, the Yamanaka factors had negligible effects.
Scientists are wary about using Yamanaka factors in humans because earlier experiments have shown that fully reprogrammed cells can create clusters of cancerous tissue called teratomas.
This study has proven that partial reprogramming can reverse aged tissues without risks, but more research is needed.
Rather than relying on Yamanaka factors which can potentially cause adverse effects, many scientists think that new drugs are necessary for a person’s body cell(s) to rejuvenate themselves and stay youthful.
Will these findings ever be used on humans? In theory, it may be possible to reverse aging. But, this is an entirely new field of science. There is much more work to be done.
Some scientists have declared that it is impossible to become immortal, reverse aging, or even see a dramatic increase in lifespan because the very things we need to survive, such as oxygen, sunlight, sugars, etc., even at normal levels, are the direct cause of our aging and eventual death. Many hurdles lie ahead.
Using the Yamanaka factors will risk inducing cancer in humans. Unlike mice, people have many more mutations that might predispose them to cancer at an older age.
In recent research, it was found that there is a risk of cell identity loss and age reversal when Yamanaka factors are used. Research teams are now working on timing, dosage, and combinations with the hope of minimizing this risk at all costs.
Now that they know these two effects can be distinct in their trajectory, other groups have been searching for new factors that will uncouple cell identity loss from rejuvenation effects.
Cellular Age Reversal In Humans
The good news is that in March 2020, researchers from Stanford University declared that they used the Yamanaka factors to rejuvenate human cells and reprogrammed them back to a youthful state. They rejuvenated aged cartilage cells from patients with osteoarthritis and muscle stem cells.
So, reversing cellular aging may not be as far-fetched as some scientists believe, and with this recent study, it may be right around the corner.