The first C. elegans worm genetically manipulated to have a longer lifespan was resistant to stress caused by heat. Subsequently, researchers learned that a common thread among all long-lived animals is that their cells (and in some cases the animals as a whole) are more resistant to a variety of stresses, compared to animals with an average or shorter lifespan.
Scientists also found that age-related dam-
and if these longer-lived animals are resis-
age to DNA and proteins is often reversible
tant to all or only certain sources of stress.
and does not cause problems until the dam-
In addition, researchers are studying
age evokes a stress response. This suggests
the relationship between psychological
that the stress response, rather than the
stress and aging. In one study, mothers of
damage itself, is partially responsible for
severely and chronically sick children had
age-related deterioration.
shorter telomeres, relative to other women.
Some biologists have started looking
In other research, caregivers of people with
at stress resistance when choosing animal
Alzheimer’s disease were found to have
models to study as examples of successful
shortened telomeres. These findings could
aging. Researchers can test stress resistance
suggest that emotional or psychological
in young animals and then continue study-
stress might affect the aging process. More
ing only those animals demonstrating high
research on the mechanisms involved is
resistance. Ongoing studies will determine
needed before scientists can make any
if there is a direct cause-effect relationship
conclusions about clinical implications.
between stress resistance and longevity,
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