Scientists at Babraham Institute have develop a new technique for look younger skin cells. This technique has allow scientists to rewind the cellular biological clock by around 30 years according to molecular measures, significantly longer than previous reprogramming methods.
The results of the research were publish in the journal, ‘eLife‘.
Scientists have able to partly restore the function of older cells, as well as rejuvenate the molecular measures of biological age.
As we age, our cells’ ability to function declines and the genome accumulates marks of ageing.
Regenerative biology aims to repair or replace cells including old ones.
One of the most important tools in regenerative biology is our ability to create ‘induce’ stem cells.
The process is a result of many steps, each erasing some of the marks that make cells specialised. In theory, these stem cells have the potential to become any cell type, but scientists aren’t yet able to reliably recreate the conditions to re-differentiate stem cells into all cell types.
The new method which is base on the Nobel Prize-winning technique scientists use to make stem cells, overcomes the problem of entirely erasing cell identity by halting reprogramming part of the way through the process.
This allow researchers to find the precise balance between reprogramming cells, making them biologically younger, while still being able to regain their specialise cell function.
In 2007, Shinya Yamanaka was the first scientist to turn normal cells, which have a specific function, into stem cells that have the special ability to develop into any cell type.
The full process of stem cell reprogramming takes around 50 days using four key molecules call as the Yamanaka factors.
The new method, called ‘maturation phase transient reprogramming‘, exposes cells to Yamanaka factors for just 13 days.
At this point, age-related changes are removed and the cells have temporarily lost their identity.
The partly reprogrammed cells were given time to grow under normal conditions, to observe whether their specific skin cell function returned.
Genome analysis show that cells had regaine markers characteristic of skin cells (fibroblasts), and this was confirm by observing collagen production in the reprogrammed cells.
To show that the cells had rejuvenate, the researchers look for changes in the hallmarks of ageing.
As explain by Dr Diljeet Gill, a postdoc in Wolf Reik’s lab at the Institute who conduct the work as a PhD student :
Researchers look at multiple measures of cellular age.
The first is the epigenetic clock, where chemical tags present throughout the genome indicate age.
The second is the transcriptome, all the gene readouts produce by the cell.
By these two measures, the reprogrammed cells match the profile of cells that were 30 years younger compare to the reference data sets.
The potential applications of this technique are dependent on the cells not only appearing younger but functioning like young cells too.
Fibroblasts produce collagen, a molecule found in bones, skin tendons and ligaments, helping provide structure to tissues and heal wounds.
The rejuvenated fibroblasts produce more collagen proteins compare to control cells that did not undergo the reprogramming process.
Fibroblasts also move into areas that need repairing.
Researchers test the partially rejuvenated cells by creating an artificial cut in a layer of cells in a dish.
They found that their treat fibroblasts move into the gap faster than older cells.
This is a promising sign that one day this research could eventually be use to create cells that are better at healing wounds.
In the future, this research may also open up other therapeutic possibilities.
The researchers observe that their method also had an effect on other genes link to age-relate diseases and symptoms.
The APBA2 gene, associate with Alzheimer’s disease, and the MAF gene with a role in the development of cataracts, both show changes towards youthful levels of transcription.
The mechanism behind the successful transient reprogramming is not yet fully understood and is the next piece of the puzzle to explore.
The researchers speculate that key areas of the genome involved in shaping cell identity might escape the reprogramming process.
Dr Diljeet Gill conclude :
Professor Wolf Reik, a group leader in the Epigenetics research programme who has recently moved to lead the Altos Labs Cambridge Institute, Said :