http://www.sciencedaily.com/releases/2009/01/090116123129.htm

Scientists Discover Gene Responsible For Brain's Aging

ScienceDaily (Jan. 18, 2009) — Will scientists one day be able to slow
the aging
of the brain and prevent diseases such as Alzheimer's and Parkinson's?
Perhaps --
at least once the genetic coding associated with neuronal degeneration
has been unraveled.

According to a new study published in The Journal of Neuroscience, a
research team
from the Université de Montréal, Maisonneuve-Rosemont Hospital and Lawrence
Berkeley National Laboratory has taken a giant step in this direction by
identifying
a gene that controls the normal and pathological aging of neurons in the
central
nervous system: Bmi1.

The primary risk factor for diseases such as macular degeneration,
Parkinson's and
Alzheimer's is age. Although many researchers have sought to better
understand the
genetics and pathophysiology of these diseases, few studies have focused
on the
basic molecular mechanisms that control neuronal aging.

Dr. Gilbert Bernier, of the Université de Montréal and Maisonneuve-Rosemont
Hospital, led a team that identified a mutation in mice that
dramatically accelerates
the process of aging in the brain and the eye. The new study reveals
that neurons
in the retina and cerebral cortex require a gene called Bmi1 to prevent
activation
of the p53 pathway and the accumulation of free radicals.

"Overall, we have now established that the Bmi1 gene is a direct
regulator of cell
aging in brain and retinal neurons of mammals through its action on the
defense
mechanisms against free radicals," says Dr. Bernier.

The article is the work of Dr. Gilbert Bernier in collaboration with
Wassim Chatoo,
Mohammed Abdouh, Jocelyn David, Marie-Pier Champagne, José Ferreira from
the Université de Montréal and Maisonneuve-Rosemont Hospital with Francis
Rodier from the Lawrence Berkeley National Laboratory, San Francisco, U.S.