lunes, 29 de noviembre de 2010

DNA trick throws ageing into reverse

A technique to keep the tips of your chromosomes healthy could reverse tissue ageing. The work, which was done in mice, is yet more evidence of a causal link between chromosome length and age-related disease.
Telomeres, the caps of DNA which protect the ends of chromosomes, shorten every time cells divide. But cells stop dividing and die when telomeres drop below a certain length – a normal part of ageing. The enzyme telomerase slows this degradation by adding new DNA to the ends of telomeres.
Mariela Jaskelioff and her colleagues at the Dana Farber Cancer Institute in Boston, Massachusetts, engineered mice with short telomeres and inactive telomerase to see what would happen when they turned the enzyme back on. These mice had shorter lifespans, atrophied organs and smaller brains than mice that hadn't been engineered.
Four weeks after the team switched on the enzyme, they found that tissue had regenerated in several organs, new brain cells were developing and the mice were living longer.
Journal reference: Nature, DOI: 10.1038/nature09603

**published in "New Scientist"