Tuesday, August 25, 2009
Anti-ageing pill activates telomerase
Peter Pan stayed forever young in Neverland. In real life, some scientists are looking at telomeres, or regions of repetitive DNA at the ends of our chromosomes, to try to arrive at something like a real version of this story.
Telomeres consist of up to 3,300 repeats of the DNA sequence TTAGGG. They protect chromosome ends from being mistaken for broken pieces of DNA that would otherwise be fixed by cellular repair machinery. But every time our cells divide, the telomeres shrink. When they get short enough, our cells no longer divide and our body stops making those cells. Over time, this leads to aging and death.
New York-based T.A. Sciences claims to be the only company in the world manufacturing a supplement in a pill form that has been lab tested and shown to stop telomeres from shortening, in hopes of halting the aging process. The product, TA-65, comes from extracts of the Chinese herb astragalus, which has been used for medicinal purposes for more than 1,000 years, says Noel Patton, chief executive officer of the company.
TA-65 is produced at very low levels in the astragalus plant, but the company purifies and concentrates the substance, which is thought to "turn on" the enzyme telomerase (hTERT) that acts to maintain or lengthen telomeres. hTERT is usually "off" in adult cells, except in immune, egg and sperm cells, and in malignant cancer-forming cells.
Telomerase is the same enzyme that allows cancer cells to stop aging or to become immortal, so there is a chance that TA-65 could keep alive cancer cells that would otherwise die.
However, telomerase activation should keep all telomeres longer in the first place, and that actually reduces the chances of cells becoming cancerous. The enzyme should keep immune cells, which can fight off most cancerous cells, alive longer.