Summary: Telomere shortening probably doesn't cause Hutchinson-Gilford progeria
Interestingness: 6
Paper by W Ted Brown in the Journal of Anti-Aging Medicine, Volume 2, Issue 2, Summer 1999.
(((
This is a short note speculating on whether progeria is caused by telomere shortening. The author says unlikely. Hutchinson-Gilford progeria is a fucking rare disease (1 in 8 million) of the type that pop up through a dominant spontaneous DNA mutation. Progerias are diseases that look like accelerated aging. This one starts being noticeable in toddlers between one and two years old, then they start looking old very quickly, going bald and losing subcutaneous fat, and have an expected lifespan of 13 years. 80% of them die of heart attacks and congestive heart failure, but they don't seem to get cancer, cataracts, osteoporosis or Alzheimer's like regular old people.
Fibroblast cultures extracted from progeria patients have an almost normal lifespan, but one paper reported shorter telomeres in them. Studies from Werner's syndrome, a different progeria that hits during early adulthood, give mixed results for shorter telomeres, but maybe some indication of faster telomere shortening.
Mice with telomerase knocked out don't show too many problems and in one study, could reproduce for at least six generations. By the sixth generation, their telomeres were much shorter and there were a lot of chromosome fusions. Other studies on these telomerase knockouts showed slightly lower lifespan, lower wound healing capacity, and more cancer. From this, he says it seems unlikely that telomere shortening would cause progeria. From what I remember, though, mice have way longer telomeres than humans to begin with, which would hide the effect a bit, but he didn't discuss that
)))
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment