Organ rejuvenation in mice

Scientists have observed signs of rejuvenation in the pancreas, liver, spleen, and blood of mice after applying one cycle of cell reprogramming 

All tissues in our bodies are characterised by having highly specialised cells, such as neurons or muscle cells, among many others. The identity of these cells was considered fixed and inflexible until the Japanese researcher Shinya Yamanaka found a way to alter their identity (that is to say, "reprogram them") by introducing high levels of four proteins, called the "Yamanaka factors" (OCT4, SOX2, KLF4 and MYC), into them. Although these proteins can be found in some of our cells, it is the simultaneous presence of high levels of all four that can alter cell identity.

This rejuvenation technique allows something previously unimaginable, namely taking cells that are easy to obtain from a patient (such as skin cells) and converting them into others that are difficult or impossible to collect, for example, heart cells or neurons, which can then be used for cell therapy applications.

To their surprise, Dr. Izpisúa-Belmonte´s team observed that when this partial and reversible reprogramming process was repeated over multiple cycles, it resulted in the cellular rejuvenation of the whole organism, making the mice healthier and better protected to a variety of diseases.

In this latest study, published in the journal Aging Cell, the researchers have examined the effects of a single cycle of Yamanaka factor stimulation in order to better define the mechanisms involved. To this end, they have probed the changes in metabolism, gene expression and cellular DNA status that occur during ageing and how these changes are partially reversed by reprogramming.