Protection for Aging Brains
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From: Peter Langston <psl>
Date: Sat, 25 Sep 99 12:39:43 -0700
Subject: Protection for Aging Brains
X-Lib-of-Cong-ISSN: 1098-7649 -=[ Fun_People ]=-
Berry good protection for aging brains
Science News, Vol 156, 9/18/99, p.180
It's depressing to contemplate the memory loss and physical infirmity
that so often accompany aging. Federal scientists, however, now report
that the blues may constitute a palatable prescription for fighting the
ravages of growing old--if, that is, those blues are berries.
The body creates oxidants, chemically reactive molecular fragments, to
eliminate old cells, infectious agents, and damaged tissue. When all goes
well, natural antioxidants quickly step in to limit the process before it
gets out of hand. As animals age, however, their antioxidant production
wanes. Indeed, oxidation underlies many degenerative changes that come with
aging (SN: 8/10/96 p. 95).
Last year, chemists at the Agriculture Department's Human Nutrition
Research Center on Aging (RNRCA) at Tufts University in Boston found that
blueberries are a rich source of pigments, called flavonoids, that show
strong antioxidant activity. Their earlier data showed that spinach and
strawberries contain copious amounts of other antioxidants.
Colleagues in a neighboring lab have now supplemented the standard
rodent food with a powdered form of blueberries, strawberries, or spinach.
The researchers added the supplements in amounts having equal antioxidant
activity. Ten 19-month-old rats received each type of supplemented rations.
In terms of life span, these animals were on par with people in their 60s.
After 8 weeks, the scientists put each animal through a number of tests.
These included mazes, walking a narrow plank, and balancing on a spinning
rod. Afterward. the researchers removed and examined each animal's brain.
Though all supplemented animals performed better on memory tests than
the 10 rats that got undoctored chow, only the blueberry group showed
notable improvements over the control group in every test of motor
coordination. James A. Joseph of HNRCA and his colleagues report their
findings in the Sept. 15 Journal of Neuroscience.
After eating blueberry-laced chow for 2 months, 21-month-old animals
outperformed unsupplemented, younger rats, Joseph says. "So, we got
reversals in age-related declines." The blueberries that each animal downed
were equivalent, when adjusted for body weight, to 1 cup daily in a person's
diet, he notes.
The scientists measured a variety of chemical-signaling characteristics
in each rat's striatum, a brain region pivotal to coordination. Each
supplement showed a different benefit pattern, Joseph says, suggesting that
blueberries' protectiveness may trace to more than oxidant quenching.
"A next important step in the research will be to see if the
improvements are long lasting," says Molly Wagster of the National
Institute on Aging in Bethesda, Md., which funded the study in part.
The differential benefits seen with the three diets reinforce what many
other recent studies have suggested: "All antioxidants aren't alike,"
observes William A. Pryor of Louisiana State University in Baton Rouge.
Some reach different places in the body; others do more than halt oxidation,
It's therefore important, he argues, not to rely on supplements
containing a single antioxidant, such as vitamin E. "You've still got
to eat plenty of different fruits and vegetables," Pryor says. Since
pigments can be very potent antioxidants, he prizes deeply colored
foods-especially "anything blue." -J. Raloff
© 1999 Peter Langston