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Commercial sunscreens reduce the
amount of sunray exposure, but fail to
protect against the damage caused
by solar radiation that penetrates our
skin every day. New research findings
show how certain plant extracts can
enhance
protection against routine
sun exposure and how they may
also help reverse the cumulative effects
of photoaging. This research also
provides persuasive evidence that the
proper use of these plant extracts may
significantly reduce skin cancer risk.In
this article, we discuss scientifically
substantiated plant extracts that have
shown potential in reversing
sun damage in order to restore a
more youthful appearance to the skin.
Prevention Is the First Step
The most effective way to preserve
one’s skin health is to avoid exposure
to the sun’s damaging ultraviolet (UV)
rays. Although this advice may seem
obvious, a surprising number of people
fail to grasp its importance.
Ultraviolet A and ultraviolet B (UVA and
UVB) radiation exert cumulative damaging
effects on the tissues most responsible
for maintaining the skin’s youthful
appearance. Scientists refer to this
process as “photoaging.”1
Cosmetic concerns aside, it is
important to remember that
sun exposure is also associated
with heightened risk of skin cancer. In
fact, as one scientist aptly noted,
“Ultraviolet radiation in sunlight is
the most prominent and ubiquitous
physical carcinogen (cancer-causing
agent) in our natural environment.”2
Make no mistake: skin cancer is directly
related to excess UV exposure. In fact,
it has been estimated that 90% of all
skin cancers result from exposure to
solar ultraviolet radiation.3,4
While this is especially true among
fair-skinned, blue-eyed people who do
not tan well, no one is safe from
overexposure to the
sun. Even riding in the car with
the windows up is no guarantee against
sunburn. Studies show that, while
automobile and household window glasses
screen out UVB rays, they provide
inadequate
protection from damaging UVA
rays,5,6
which is one more reason to include a
broad-spectrum sun-screen in your daily
health regimen.
Skin Cancer: Public Enemy Number One
Skin cancers account for more than
50% of all cancers. Even if one ignores
potentially lethal melanomas,
non-melanoma skin cancer remains the
most common malignancy in humans. In the
United States, the incidence of
non-melanoma skin cancers—squamous and
basal cell carcinomas—is equal to the
incidence of malignancies in all other
organs combined.7
As noted earlier, sunburn damage is
cumulative; while some damage is bad,
more damage is even worse. It is never
too late to prevent additional damage,
and it may be possible to significantly
reverse some damage that has already
been sustained.
This is because recent advances in
skin-care science have yielded new
approaches to skin repair and
restoration. Researchers have discovered
botanical extracts that penetrate the
outer layers of the skin (epidermis) to
reach the dermis, the living layer where
skin is constantly repaired and renewed.
These extracts have been clinically
shown to activate the body’s own repair
mechanisms, prompting the reversal of
ultraviolet-light-induced damage.
Several of these compounds—including
phytochemicals derived from green tea,
licorice root, milk thistle, and
rosemary—have been available to
consumers for several years. Now,
scientists have identified an exciting
new skin-protective agent called beta-glucans.
Derived from oats, beta-glucans
stimulate the dermal layers of skin to
promote remarkable healing and repair
from within.
Promoting skin collagen synthesis
Beta-glucans represent an exciting
new development in the “wrinkle wars.”
Beta-glucans combined with a collagen
matrix are approved by the FDA for use
in wound repair among burn victims,8
and beta-glucans have shown great
promise in combating the potentially
serious tissue damage associated with
bedsores.9
It was long believed that the large
size of beta-glucans made these
bioactive molecules incapable of
penetrating the outer layers of intact,
erstwhile healthy skin. However, a
unique process now allows scientists to
extract smaller molecules of beta-glucans
from whole grain oats. These “designer”
beta-glucans nevertheless retain the
immune-stimulating properties of beta-glucans
used for oral applications. Moreover, as
we shall see, they are adept at
promoting collagen synthesis by directly
stimulating connective tissue cells
within the dermis.
Beta-Glucans for Dermal Repair
Oral supplementation with beta-glucans
has been shown to enhance the activity
and effectiveness of the body’s immune
system.10
Beta-glucans accomplish this by
stimulating the activation of
macrophages, or white blood cells.11
Macrophages identify, engulf, and
destroy bacteria and cancer cells.
Macrophages possess specialized
receptors that are programmed to
recognize and interact with beta-glucans.
A given beta-glucan molecule fits into a
receptor like a key into a lock, which
then “turns on” the macrophage. In the
skin, macrophages are enlisted to remove
dead cells and help repair wounds. This
is where topically applied beta-glucans
come in.
Tailor-Made Beta-glucans
Scientists have developed a novel
form of beta-glucans that readily
penetrate the outer layer of the skin
(the stratum corneum), moving down
through the epidermis to the living
dermal tissue. They believe that these
beta-glucans work to benefit the skin in
several ways.
First, when applied topically, they
form a thin film over the stratum
corneum, locking in moisture. Second,
they are thought to penetrate deeper
layers and circulate in the spaces
between live skin cells (keratinocytes)
and connective tissue cells
(fibroblasts). Here, scientists believe
that they stimulate fibroblasts to
produce procollagen and collagen,
probably by eliciting the release of
certain growth factors.12
This reverses some of the undesirable
changes in skin associated with aging
and cumulative
sun damage—changes that are
directly related to loss of collagen and
procollagen.1
Finally, both systemic and topically
applied beta-glucans have been shown to
help speed the healing of burn-induced tissue
damage, in part by restoring depleted
levels of antioxidants.13
It has long been thought that beta-glucans
indirectly affect collagen synthesis by
stimulating macrophages to release
cytokines (proteins that act as cellular
mediators), thus stimulating fibroblasts
to produce more collagen.9,12,14,15
However, more recent research shows that
fibroblasts themselves are studded with
specific receptors for beta-glucans.16,17
When glucan molecules bind with these
receptors, fibroblasts release proteins
known as transcription factors, which
initiate genetic transcription.
Transcription is the first step in the
cellular process that produces new
molecules tailored to perform
specialized tasks.12,14
Specifically, beta-glucans stimulate
fibroblasts to activate genes involved
in collagen synthesis18
and to release an array of growth
factors that are intimately associated
with wound repair and the production of
healthy new skin tissue.16
The result is smoother, more
youthful-looking skin.
Nature’s Arsenal Against Photoaging
Beta-glucans are just one of many
natural substances that directly benefit
skin. The active ingredients in
commercial sunscreens are usually
limited to zinc oxide or titanium
dioxide to serve as a physical barrier
against UV radiation, often in
combination with avobenzone or
dioxybenzone, which provide approved
sun-protection-factor (SPF) ratings.19
There are, however, naturally occurring
compounds that
protect against light-induced
damage and help skin repair and
regenerate from within.
According to leading photoaging
researchers at the University of Alabama
at Birmingham, “In recent years,
considerable interest has been focused
on identifying naturally occurring
botanicals, specifically dietary, for
the prevention of photocarcinogenesis.”20
Noting that grape seed proanthocyanidins, silymarin (from
milk thistle), and green tea
polyphenols, among other botanicals,
show great promise, they add, “These
botanicals may favorably supplement
sunscreen
protection and may provide
additional antiphotocarcinogenic
protection, including
protection against other skin
disorders caused by solar UV radiation.”20
This investigative team recently
published a review of research that
shows how the above-mentioned botanical
compounds act to prevent and even
reverse some of the damage associated
with UV exposure. Researcher Santosh K.
Katiyar details several molecular
mechanisms by which these botanical
compounds
protect against cancer,
concluding, “The new information
regarding the mechanisms of action of
these agents supports their potential
use as adjuncts in the prevention of
[UV-induced cancers].”21
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