Turning Back the Internal Clock
""To do it, a research team led by Helen Blau delivered a bioengineered version of messenger RNA that encodes a telomere-extending protein to cultured human cells. In this case, the RNA contained a coding sequence called TERT, which is the active component of telomerase.
After this treatment, the cells performed as if they were much younger than the untreated cells; they happily multiplied away instead of degrading or dying as per usual. Overall, the treated cells were able to divide up to 40 more times than untreated cells.
"Now we have found a way to lengthen human telomeres by as much as 1,000 nucleotides, turning back the internal clock in these cells by the equivalent of many years of human life," noted Blau in a release. "This greatly increases the number of cells available for studies such as drug testing or disease modeling."
The 1,000 nucleotide addition represents a 10% increase in the length of the telomeres.
The new technique has been applied to such cell types as fibroblasts (common cells of connective tissue) and myoblasts (cells that give rise to muscle cells), and is currently being tested on stem cells.
A Temporary Effect By Design
Importantly, the treatment is temporary, lasting about 48 hours. The modified RNA reduces the cell's immune response to the treatment to allow the TERT-encoding message to hang around longer than an unmodified message. This means the cells were not immortalized; after a couple of days, the modified telomeres revert back to normal. As noted in the release, this transient effect is akin to:
...tapping the gas pedal in one of a fleet of cars coasting slowly to a stop. The car with the extra surge of energy will go farther than its peers, but it will still come to an eventual halt when its forward momentum is spent. On a biological level, this means the treated cells don't go on to divide indefinitely, which would make them too dangerous to use as a potential therapy in humans because of the risk of cancer.
Indeed, increased telomerase activity in humans has been linked to cancer. Clearly, there will be limits to how this new biotechnology can be used to combat various aging-related diseases.""
The Revitalizing Report:
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