A study centering on an embryonic stem cell gene known as Nanog, was found to restore the regenerative properties of adult stem cells, which diminish over time. Researchers think this process has the potential to slow or reverse the effects of aging, as well as combat premature aging disorders such as progeria.
Previous research into slowing the aging process has involved blocking pathways in the brain that produce certain protein complexes, switching back on genes that have been turned off due to epigenetic regulation, and activating a gene that increased the lifespan of common fruit flies.
This new study, by researchers from University at Buffalo (UB), focused on adult stem cells, nonspecialized cells that are found throughout the body and can rush in to replenish dying cells as required. The problem is, as people get older, these stem cells become less and less effective, which results in the well-known symptoms and disorders of aging.
Introducing Nanog into aged stem cells triggered a chain reaction that helps those cells regain their former regeneration abilities. First, Nanog opened two key cellular pathways, known as Rho-associated protein kinase (ROCK) and Transforming growth factor beta (TGF-β). As a result, dormant proteins called actin are reactivated, which provide the stem cells with the structure needed to form muscle cells that can contract. The force these cells generate helps improve the regeneration capabilities of the adult stem cells.
The team conducted tests on three different samples of cells aged in different ways: cells taken from aged donors, cells aged in culture in the lab, and those isolated from patients suffering from Hutchinson-Gilford progeria syndrome, a rare genetic disorder that ages sufferers at an accelerated rate. The Nanog gene was found to work in all three cases.
"Not only does Nanog have the capacity to delay aging, it has the potential in some cases to reverse it," says Stelios Andreadis, one of the authors of the study.
Nanog was also shown to activate the central regulator of muscle formation, serum response factor (SRF), which suggests that the same effect could be achieved in skeletal, cardiac and other muscles types. The researchers are now working to identify drugs that can replicate or mimic the effects of Nanog.