Main Category:
Cosmetic Medicine / Plastic Surgery News
Article Date: 21 Aug 2006 - 0:00am (PDT)
|
email this article |
printer friendly |
view or write opinions |
As the public's appetite grows for more “natural” health
remedies, there is a concomitant demand from physicians
and governments to document the benefits and effects of
some herbs. In partial response, a team of researchers
has recently investigated three common medicinal herbs
-- Echinacea purpurea, Astragalus membranaceus, and
Glycyrrhiza glabra - and found them to be effective in
boosting key blood lymphocytes, the basic building block
of the body's immune system.
Background
Echinacea, Astragalus and Glycyrrhiza have been used
historically and are used today to enhance the immune
system. Echninacea has been used for centuries by Native
Americans, and is one of the most commonly used herbs
for respiratory tract infections. Astragalus is primarly
used in Chinese medicine as a tonic, to prevent colds
and aid the spleen and lungs. Glycyrrhiza (licorice) has
been used medicinally since the beginning of recorded
history, and is widely used today in Indian and Chinese
medicine. For centuries the herb has been used to treat
respiratory, gastrointestinal and cardiovascular
conditions.
Most of the existing research into the mechanism of
these herbs has been conducted in animal models. To
measure the effects in humans, researchers must examine
the impact the herbs have on cell activation in
lymphocytes. Lymphocytes are a type of white blood cell
and come in three forms: B cells, which make antibodies
that bind to a virus or micro-organism and then destroy
it; CD4 T cells, which coordinate the immune system's
response; and CD8 T cells, which kill cells that become
infected.
A New Study
The authors of a new study entitled, “The Effect of
Echinacea purpurea, Astragalus membranaceus, and
Glycyrrhiza glabra Immune Cell Activation and
Proliferation in Humans” are Julie Brush, ND, Elissa
Mendenhall, ND, Alan Guggenheim, Tracy Chan, ND, Erin
Connelly, MA, Richard Barrett, ND, and Heather Zwickey,
Ph.D., all from the Helfgott Research Institute,
National College of Natural Medicine, Portland, OR;
(Note: Dr. Zwickey is also Director of the Helfgott
Research Institute); Amala Soumyanath, Ph.D., from the
Oregon Health and Science University, Portland, OR; and
Randal Buresh, from Oregon's Wild Harvest, Sandy, OR. An
American Medical Association Seed Grant, Helfgott
Research Seed Fund Grant, and Oregon's Wild Harvest
funded this study.
Dr. Zwickey will present her team's findings at the 21st
Annual Meeting of the American Association of
Naturopathic Physicians (http://www.Naturopathic.org),
being held August 9-12, 2006 at the Oregon Convention
Center, Portland, OR.
Methodology
Sixteen healthy subjects participated in a double-blind,
placebo controlled, randomized clinical trial. The
subjects were randomized to solutions of Echinacea only,
Astragalus only, Glycyrrhiza only, the combination of
all three in equal parts, and placebo. The subjects
received a 7.5 ml dose twice a day for seven days.
Peripheral blood was drawn from the subjects three
times: before ingesting the herbal solution, after 24
hours, and seven days after herbal ingestion. White
blood cells were separated from whole blood and analyzed
to determine immune activation through the cell surface
protein CD69. Immune regulation was determined by CD25
expression on CD4 T cells.
Results
The researchers found that:
-- Echinacea and Glycyrrhiza were able to stimulate
proliferation of CD4 T cells, CD8 T cells and NK cells
when administered orally to the study subjects.
-- All three herbs -- administered either singly or in
combination -- were able to activate CD8 T cells.
Astragalus caused the most activation.
-- Glycyrrhiza was able to stimulate NK activation.
-- All the subjects who received Echinacea tincture
showed CD25 activation at 24 hours compared to 0 hours,
which persisted at seven days.
-- Of great interest to the researchers was the
simultaneous expression of activation (CD69) and
regulation (CD25), present in the same patients.
Conclusions
The results demonstrate that Echinacea, Astragalus, and
Glycyrrhiza herbal tinctures stimulate CD4 T and CD8 T
cells. Thus, the authors believe that these herbs do
work in enhancing the immune system, but are likely to
be most effective when the essential medical qualities
are applied in a certain application. The team also
stated that this study, supported by the naturopathic
and medical communities, demonstrates that further
collaborative research on the use of the herbs in
enhancing the body's immune system is warranted.
The American Association of Naturopathic Physicians (AANP)
was founded in 1985 to provide alternative methods for
healing human diseases and disorders than have been
traditionally offered in the United States. Members of
the AANP must have graduated from one of North America's
six accredited graduate schools of naturopathic
medicine.
http://www.naturopathic.org/
