In December 2016, scientists at the Salk Institute have found that the intermittent expression of genes normally associated with an embryonic state can reverse some aspects of aging . In particular, their approach reversed the epigenetic changes that occur in cells as we age and that switch gene expression from a healthy, youthful profile to an unhealthy, aged one.
During the study, they not only made aged human skin cells in a dish function like young cells again, they also rejuvenated mice that suffered from a premature aging disease, countering the signs of aging and increasing their lifespan by 30 percent.
As people are living longer, their risk of developing age-related diseases is increasing. Age is the single greatest risk factor for heart disease, cancer, neurodegenerative disorders, and many more.
Scientists believe that the most effective way to prevent or reverse age-related diseases is not to try to compensate for them as current medicine does but to target aging directly. One potential way to achieve this lies in the study of cellular reprogramming, a process in which the expression of four genes known as the Yamanaka factors (also known as OSKM) allows scientists to change any cell into induced pluripotent stem cells (iPSCs). Like embryonic stem cells, iPSCs are capable of dividing indefinitely and becoming any cell type present in our body.
Researchers at the Salk Institute have found that if these reprogramming signals are sent to cells for a very short period, then a partial reprogramming occurs. This means that the cells do not fully change into iPSCs and thus forget their current roles in the tissues of which they are part, but they do reset their epigenetic markers which cause them to reset so that they are functionally younger again.
Their research now confirms that this approach is possible not only in cells but is also plausible in living animals and that it makes them functionally younger and healthy for longer. The next question was whether they can translate this technique to humans; they believe so and are aiming to bring this to the clinic within the next decade.
 Ocampo, A., Reddy, P., Martinez-Redondo, P., Platero-Luengo, A., Hatanaka, F., Hishida, T., … & Araoka, T. (2016). In vivo amelioration of age-associated hallmarks by partial reprogramming. Cell, 167(7), 1719-1733.