2–3
weeks
Life span of
a C. elegans
roundworm
2–3
years
Life span of
a laboratory
mouse
2–3
decades
Life span
of a rhesus
macaque
Worms live longer with thioflavin T
dye used in alzheimer’s research promotes longevity in lab
By Daniel Strain
Wriggly roundworms (Caenorhabditis
elegans) have found themselves a philosopher’s stone of sorts. A dye used to
visualize the proteins that build up in the
brains of Alzheimer’s patients can boost
a worm’s two- to three-week life span by
more than half, Gordon Lithgow of the
Buck Institute for Research on Aging in
Novato, Calif., and his colleagues report
online March 30 in Nature. The dye, called
thioflavin T, seems to prevent the deviant
protein clumps often associated with a
number of human age-related diseases,
including Alzheimer’s, researchers say.
During aging, the body accumulates
proteins that aren’t shaped, or “folded,”
the way they should be, says Richard
Morimoto, a molecular biologist at North-
western University in Evanston, Ill. For
reasons that remain a hot topic of study,
misshapen proteins often sit in big clumps
that have been spotted in any number of
chronic illnesses from Alzheimer’s to Par-
kinson’s and Huntington’s disease. “The
underpinning for all these diseases may
be aging,” Morimoto says.
Brain cell growth
restores function
New neurons help patch up
learning, memory after injury
decade that two regions in adult
brains can make new neurons,
the role of the newborn cells
has been unclear. Some thought
that new neurons may not affect
the adult brain at all.
The study suggests that ne w-
born neurons in the hippocam-
pus — an important learning
and memory center — are
beneficial, at least in aiding
recovery after traumatic brain
injuries. “It’s clear they are
doing something, and that that some-
thing aids recovery,” says Jack Parent,
a neurologist and neuroscientist at the
University of Michigan Medical Center.
To discover what role, if any, neuro-genesis plays after a brain injury, the
Texas team genetically labeled newborn cells in the hippocampi of mice.
The researchers found that traumatic
brain injury stimulates birth of more
By Tina Hesman Saey
Newborn nerve cells may help heal the
brain after a traumatic injury.
In mice, blocking the birth of new neurons hindered the animals’ ability to learn
and remember a water maze after a brain
injury, Steven Kernie and colleagues from
the University of Texas Southwestern
Medical Center at Dallas report in the
March 30 Journal of Neuroscience. The
finding could help settle a debate about
what new nerve cells do for the brain and
may eventually change the way brain-injured patients are treated.
Although scientists have known for a
uninjured control Six months after injury
Injury can trigger the birth of new neurons in the
brain. More treelike neurons were seen in mice
after injury (right) than in uninjured mice (left).
brain cells than usual. Using another
genetic technique, the researchers
blocked the regrowth in some mice.
Mice that couldn’t make new brain cells
didn’t recover the ability to learn a water
maze after brain injury as effectively as
mice that could generate new neurons.
The result indicates that newborn neurons play a role in learning that involves
the hippocampus.
