An anti-aging pill: it could be a reality sooner than we think but how would it work and is it something we really want? Dr Hannah Sweilam takes a look.
There’s a plethora of potions and lotions available to help diminish signs of ageing but no one has found a way to actually stop or turn back the clock….or have they? As it happens, they have, and an end to wrinkles could be in sight.
Scientist believe they may be a decade away from starting trials of medications that will literally halt the aging process in its tracks and even turn back the clock. It’s an approach that turns the traditional view of aging on its head. No longer will it be regarded as the natural progression of life but instead it will be a treatable condition.
It’s a development that raises as many ethical questions as it does medical in terms of who would have access – only the rich? Could society deal with people living an extra 30 years or so, even if they were in reasonable health? And since we are already struggling with issues of isolation and loneliness among the aged, and in the end, do we really even want to live that long?
But before we get to that point, there are a host of medical issues to overcome, not the least of which is how to make this kind of medication safe to use.
The principle behind this anti-aging revolution is activating genes in the body to get them to clean up the debris collected in the cells that contributes to diseases and aging. It’s something scientists have been working on for a number of years in fruit flies and mice.
Cellular house-keeping slows down ageing
A group of researchers, at the University of California, have identified and activated two anti-ageing genes. These genes were studied in fruit flies- which are frequently used for genetic experiments- and when activated, the genes slowed down ageing and increased the flies’ lifespan by 30%.
The scientists found that these genes increased ‘autophagy’, which literally means to ‘self-eat’ and is a process whereby the body eliminates misshapen proteins and damaged cell parts. As we get older, our cells get worse at removing this debris which builds-up and stops cells functioning properly. Defective autophagy has been linked with age-related diseases, such as cancer and heart disease.
Likewise, skin ageing has been linked with defective autophagy. When scientists compared older human skin cells with younger ones, they found that almost 80% less autophagy occurred in the older skin cells. If autophagy in our skin cells were to be increased, it follows that skin collagen production would increase and skin would be rejuvenated.
This research helps pave the way for a therapy to enable us to periodically undergo a ‘cellular housecleaning’ to remove cell debris from our skin, brain and other tissues. This could help restore cells, slowing down ageing and helping support healthier ageing more generally.
What about actually reversing ageing?
Meanwhile, scientists in Japan and the U.S. have reprogrammed human skin cells in the lab to erase all markers of ageing.
They did this by switching on four genes, known as the ’Yamanaka’ genes. The newly reprogrammed cells lost all their features of age and instead, acted like cells obtained from an early embryo. Reprogramming the body’s cells to this extent would not be suitable for use as a treatment: we wouldn’t want our skin cells to lose their skin features and become identity-less cells, like those of an early embryo. That wouldn’t do anyone any favours, and could even cause cancer.
But scientists at the Salk Institute in California performed similar studies on living mice with a premature ageing disease called progeria. Rather than reprogram cells all the way back to an embryo-like state, they partially reprogrammed cells by activating the Yamanaka genes for a shorter duration. This reversed the hallmarks of ageing while preserving the identity of cells. Body cells were rejuvenated and returned to a more youthful state and the mice lived for 30% longer. Similarly, in non-progeria elderly mice, the same partial reprogramming appeared to give them a new lease of life, improving their recovery from disease and muscle injury.
How does reprogramming actually work?
Reprogramming works by resetting a cell’s so-called ‘epigenetic’ changes- alterations around genes that have switched them on or off. Many scientists believe that ageing is driven by epigenetic changes which have accumulated over time, propelling cells from a younger state to an increasingly weakened, older state.
As the US National Institutes of Health explains, “Many […] environmental factors, known and unknown, can cause epigenetic changes. Some epigenetic changes appear to happen on their own, without any clear cause. Some epigenetic changes happen as a result of certain types of chemical reactions in the body”. Lifestyle factors such as a high fat diet and smoking cause epigenetic changes too, as do some medications. As research has shown, epigenetic changes are not permanent.
How would all this work in practise?
Rejuvenating a human is more complex than rejuvenating a mouse (or a fruit fly for that matter) but the genetic principles are the same. In practise, epigenetic changes in humans could be reversed by using more user-friendly chemicals than those used in the Yamanaka studies, and drugs are already being developed for this purpose. Scientists predict we are 10 years away from trialling these drugs in humans.
The studies have demonstrated the fine line between benefit and harm. When researchers treated mice continually, some developed cancer and died shortly afterwards, whereas mice treated intermittently benefited noticeably. In order for age-reversal drugs to be regulated and licensed, scientists will need to prove that they reprogram cells to be young again without causing them to become cancerous.
Our concept of ageing is about to change. Many scientists no longer view ageing as an inevitable part of life but rather as something that can be moulded, manipulated and treated. It’s a subject that is set to challenge not only our expectations of ageing but of life and death and how society handles it.