Scientists say a technique of reprogramming cells can “reverse” ageing and markedly increase lifespan.
“Our study shows that ageing may not have to proceed in one single direction. It has plasticity and, with careful modulation, might be reversed,” Professor Izpisua Belmonte of the Salk Institute said.
The technique used in an experiment involved turning cells back into stem cells, which can then develop into any kind of specialist cell. Another researcher, Alejandro Ocampo explained, “What we and other stem-cell labs have observed is that when you induce cellular reprogramming, cells look younger.”
Although previous experiments using the technique on mice did produce younger cells, they also resulted in tumours that caused the mice to die. But the team’s latest research managed to achieve positive results with the mice living 30% longer than untreated animals and not getting cancer.
Scientists explained that the technique was risky because creating stem cells, which can divide rapidly and are important to embryo growth, in adults appeared to increase risk of tumours.
To prevent this, the Salk researchers changed the way four genes, which are involved in cellular programming, were expressed for a short period. Following this technique, scientists achieved the same positive test results on human cells in the laboratory. Pradeep Reddy, also a Salk research associate explained, “In other studies scientists have completely reprogrammed cells all the way back to a stem-cell-like state. But we show, for the first time, that by expressing these factors for a short duration you can maintain the cell’s identity while reversing age-associated hallmarks.”
For this reason, tests on skin cells in the lab appeared younger but still remained recognisable skin cells. The researchers also tried the technique on mice with progeria, a condition which leaves them – and humans – prematurely old.
Compared with other mice with progeria, the ones with reprogrammed cells lived 30% longer. The researchers then tried the technique on normal, elderly mice. They reported improved regeneration of muscle tissue and the pancreas after an injury.
“Obviously, mice are not humans and we know it will be much more complex to rejuvenate a person,” Professor Belmonte said. “But this study shows that ageing is a very dynamic and plastic process, and therefore will be more amenable to therapeutic interventions than we previously thought.”
This article originally appeared on The Independent.