Contact:
Christine Guilfoy
Office: (301) 634-7253
cguilfoy@the-aps.org
Steroid Plays Key
Role In Skin Abnormalities Induced By Psychological Stress
Bethesda,
Md (Dec. 1, 2006) – Inhibiting glucocorticoid, a type of steroid, can
prevent skin abnormalities induced by psychological stress, according to a
new study from the December issue of the American Journal of
Physiology-Regulatory, Integrative and Comparative Physiology.
The new study also shows how psychological stress induces skin abnormalities
that could initiate or worsen skin disorders such as psoriasis and atopic
dermatitis.
The study, “Glucocorticoid blockade reverses
psychological stress-induced abnormalities in epidermal structure and
function,” was carried out by Eung-Ho Choi, Marianne Demerjian, Debra
Crumrine, Barbara E. Brown, Theodora Mauro, Peter M. Elias and Kenneth R.
Feingold of the Veterans Affairs Medical Center, San Francisco and the
University of California at San Francisco. Choi is also associated with
Yonsei University Wonju College of Medicine, Wonju, Korea. The American
Physiological Society published the study.
Previous research has shown that psychological stress
increases glucocorticoid production. In addition, it is well recognized that
psychological stress adversely affects many skin disorders, including
psoriasis and atopic dermatitis.
“In this study, we showed that the increase in
glucocorticoids induced by psychological stress induces abnormalities in
skin structure and function, which could exacerbate skin diseases,” Feingold
explained. This provides a link for understanding how psychological stress
can adversely affect skin disorders. Blocking the production or action of
glucocorticoids prevented the skin abnormalities induced by psychological
stress.
Skin protects
The skin is the body’s largest organ and plays a
crucial role in providing a barrier between the environment and the internal
organs. It protects us from harmful microorganisms, ultraviolet light, toxic
chemicals, and more. However, its most important function is providing a
permeability barrier that prevents us from drying out. We are approximately
65 percent water and we are able to survive and function in dry environments
because the skin forms a permeability barrier that prevents the loss of
water.
The permeability barrier is located in the outermost
layer of the epidermis, the stratum corneum. The stratum corneum is composed
of dead cells surrounded by lipid membranes which mediate the permeability
barrier. The stratum corneum layer continuously sloughs off, and therefore
must be regenerated. The epidermal cells in the lower epidermis are
continuously proliferating to provide new cells, which then differentiate,
and ultimately die, to form the stratum corneum.
Previous studies have shown that psychological stress
disturbs this elegantly balanced system by decreasing epidermal cell
proliferation and inhibiting differentiation. Additionally, permeability
barrier function is impaired. The researchers hypothesized that the increase
in glucocorticoids induced by psychological stress would cause these adverse
effects on skin function.
Study with hairless mice
They tested their hypothesis by subjecting hairless
mice to stress while either blocking the production of glucocorticoids or
preventing them from acting on the body. The stress was created by placing
the mice in small cages in constant light with a radio playing for 48 hours.
Before placing the mice in the stressful situation, the
researchers treated one group of mice with RU 486, better known as the
morning-after pill, a substance that blocks the action of glucocorticoids.
A second group of mice received antalarmin, which
blocks glucocorticoid production. A third group was subjected to the stress
but received neither antalarmin nor RU 486. The fourth group, the control
group, remained unstressed in ordinary cages and without the continuous
light and sound to which the other groups were exposed.
Results confirm hypothesis
The stressed mice that received RU 486 and antalarmin
showed significantly better skin function compared to the stressed mice that
did not receive either treatment. The treated mice showed significantly
better:
The experiment demonstrated the important role that
glucocorticoids play in inducing the skin abnormalities brought on by
psychological stress. While the researchers hope the study will lead to a
way to treat people who suffer these skin conditions, there is still a long
way to go: First, the research was done with mice, not people. Second, there
may be serious side effects of modulating glucocorticoid activity.
Glucocorticoids are essential hormones that play many important roles.
Blocking the action of glucocorticoids could have negative outcomes that are
much worse than exacerbations in the skin disorders.
The research team is now looking at the effect of
psychological stress on the skin’s production of antimicrobial peptides,
which play a role in defense against infection. They hypothesize that
psychological stress might also reduce the ability of the skin to protect
from infections.
Funding
The National Institutes
of Health and the Department of Veterans Affairs Medical Center San
Francisco funded the study.
Editor’s note: The media may arrange an
interview with a member of the research team by contacting Christine Guilfoy,
American Physiological Society, (301) 634-7253 or
cguilfoy@the-aps.org.
* * *
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American Physiological Society was founded in 1887 to foster basic and
applied bioscience. The Bethesda, Maryland-based society has 10,500 members
and publishes 14 peer-reviewed journals containing almost 4,000 articles
annually.
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provides a wide range of research, educational and career support and
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