Scientists at Stanford University have found a way to extend telomeres, the protective caps at the end of our chromosomes which are linked to both disease and aging itself.
Telomeres are protective caps which sit at the end of our chromosomes and are directly linked to aging. They were discovered in the 70’s and could be compared to the plastic caps at the end of your shoelaces. They’re composed of repeating nucleotide sequences, and shield the chromosomes from deterioration. Over time, due to cell division, these telomeres are shortened, and while an enzyme process rebuilds them, they do still become smaller and smaller as we age. Shorter telomeres have been linked with diseases such as cancer.
When humans reach a certain age, and this depends on your genetics as well as on environmental factors, the telomeres will be depleted, and when this occurs, the chromosomes are left open to the environment and can be easily damaged. To put it bluntly, when your telomeres are gone, each cell division will lose a bit of the information in the chromosome and you’ll begin dying. These little protective caps set the limit to human lifespans.
Photo of chromosomes. The bright dots at the ends are the telomeres
Lucky for us, scientists at Stanford’s School of Medicine have invented a procedure which can lengthen the telomeres quickly and efficiently in laboratory grown cells. Treated cells will replicate as if they were much younger specimens. To give you some context, the average human has telomeres which originally contain 8,000-10,000 nucleotides. The procedure extended the telomeres in tested cells by as much as 1,000 nucleotides – not a small amount. In skin cells, the Stanford scientists observed cell divisions 40 times longer than in untreated cells.
The procedure involves using a modified version of RNA and will primarily be used for large scale studies of cells or for drug development. “This greatly increases the number of cells available for studies such as drug testing or disease modeling.” says Helen Blau, PhD, professor of microbiology and immunology at Stanford and director of the university’s Baxter Laboratory for Stem Cell Biology. RNA contains instructions from genes in the DNA to the protein factories in the cells. The scientists encoded the RNA with instructions for producing TERT, the active component in the enzyme telomerase. Telomerase is present in stem cells (as well as egg and sperm cells) and ensure that the telomeres remain healthy.
The key that makes this new technique so useful is that the extension is temporary. It would be bad if the telomeres lengthened endlessly. Instead, after 48 hours, the effect dissipates and the cells return to aging normally.
The lifespan of laboratory skincells was extended by 40 times
There’s more though. If you were disheartened to read that the technique would be used for studies, as opposed to extending human life, Professor Blau brings some good news. “This new approach paves the way toward preventing or treating diseases of aging,” said Blau. “There are also highly debilitating genetic diseases associated with telomere shortening that could benefit from such a potential treatment.”
“One day it may be possible to target muscle stem cells in a patient with Duchenne muscular dystrophy, for example, to extend their telomeres. There are also implications for treating conditions of aging, such as diabetes and heart disease. This has really opened the doors to consider all types of potential uses of this therapy.”