How To Live Long And Prosper: Get Dirty
- From: rpautrey2 <rpautrey2@xxxxxxxxx>
- Date: Sat, 9 Feb 2008 14:41:37 -0800 (PST)
How to Live Long and Prosper: Get Dirty?
By Robin Lloyd
Special to LiveScience
posted: 13 October, 2004 7:00 a.m. ET
Germs go both ways, helping our health at times and killing us at
others. A new study suggests they might give the gift of a long life,
at least to fruit flies.
Early exposure to bacteria makes these banana-peel denizens live to
the ripe age of about three months, according to a recent paper in
Proceedings of the National Academy of Science.
For a fruit fly, that's 30 percent longer than usual.
"In short, what we find is bacteria are good for young flies," said
biologist Ted Brummel, who was in charge of the research project while
at Caltech but is now at Sam Houston State University.
The "dirty living" effect worked only in the first week of life. In
mid-life, exposure to bacteria had no effect. And later in life, it
shortened life.
Does this mean we should cut back on infants' baths and house
grandparents in glass bubbles to live as long as Methuselah? It's not
that simple.
Before birth (or hatching,) fruit flies, like humans and most other
animals, develop in a germ-free environment. After birth, numerous
strains of bacteria set up house over time in animals' bodies.
The longevity effect of bacteria among creatures varies. Parameciums
and termites grown in sterile environments age more rapidly. For a
worm called C. elegans and for mosquitoes, such clean living harms
their development but lengthens their lives.
In recent years, scientists have shown that bacteria in humans
influence ulcers, cancer, appetite, and gut development. Certain bugs
also duke it out with other bugs in our bodies, keeping us disease
free.
To tease out a simpler case, the Caltech team studied the give and
take between bacteria and fruit flies across their lifespan. The
experiment involved raising flies in germ-free test tubes and then
controlling the timing of flies' exposure to bacteria using
antibiotics in their food. The results showed the early time window
was important. Even if flies only lived with germs in their first week
of life and then were given antibiotic-treated food for the rest of
their lives, they lived longer than those raised in total sterility.
As for humans, some scientists say that early exposure to "dirt" might
explain the lower incidence of allergies in the developing world.
The experiments also underscore the ongoing concern among health care
experts about the routine use of antibiotics. Early use of antibiotics
in humans has been linked to asthma. And over-use of antibiotics has
resulted in drug-resistant strains of tuberculosis, salmonella,
bacteria that cause pneumonia, and many others.
For now, scientists hope that more knowledge of the workings of
bacteria and longevity in fruit flies will help them design
experiments to see if the same exposure and timing mechanisms apply in
humans. The mass of all the planet's bacteria and "archaea" cousins
(both types of these single-cell organisms lack a central nucleus)
weighs as much as all the plants on Earth. Most of them live under
land or the sea floor, although a fair number of them live in the
human gut.
"The truth is," Brummel said, "we really know very little about most
of the species of bacteria living within our bodies and how they
affect our fitness."
LiveScience
© Imaginova Corp. All rights reserved.
.
- Prev by Date: War On Bacteria Is Wrongheaded
- Next by Date: Dust Storms Overseas Carry Contaminants To U.S.
- Previous by thread: War On Bacteria Is Wrongheaded
- Next by thread: Dust Storms Overseas Carry Contaminants To U.S.
- Index(es):
Relevant Pages
|
