Cancer
How the humble
raspberry
can help fight cancer – and other illnesses
by Susan Thorpe-Vargas, PhD
< Previous Page
Why don’t ellagitannins
induce normal cells to
commit suicide?
As we know, cancer cells become
immortal. This means they are able to
replicate themselves after something
called the Hayflick limit is reached.
The Hayflick limit is the number of “allowed” cellular replications. Each
cell type has its own limit. Human
cancer studies show that mutations in
the tumor suppressor gene called p53 account for many tumors. One of the
functions of this gene is that it normally
prevents cells with damaged DNA from
proceeding through the cell cycle. The
presence of the protein product encoded
by p53 turns on the waf-1 gene. The waf-1
gene produces a protein that normally
inhibits the activity of several similar
cellular proteins called kinases. These
proteins are involved in stopping cell
cycle progression. A mutation in either
the p53 or waf-1 gene can cause the loss
of that “emergency brake” function and
allow uncontrolled growth. However,
ellagitannins induce only “damaged”
cells to commit suicide, and normal cells
are not affected.
Antibacterial and
antiviral properties
Ellagitannins can also act as antibacterial
and antiviral agents, and now we know
how. Think of the genetic material of
bacteria as a rubber band that is all
twisted up. In order to replicate, the
DNA must untwist itself through a
process requiring the enzyme gyrase.
Ellagitannins inhibit gyrase activity
so replication of bacterial DNA is
restricted. More importantly, bacteria
cannot easily become resistant to this
type of antibacterial action. Resistance
to antibiotics has become a real concern
to the international medical and veterinary
community.
Ellagitannins also offer antiviral activity.
Viruses do not have the ability to replicate
themselves. Instead they must “hijack”
the host cell and insert their own DNA
into the host cell genome. This requires
several enzymes. Ellagitannins inhibit
these enzymes. They are especially
helpful with retroviruses like FIV
(feline immunodeficiency virus) and
feline leukemia virus (FeLV) as they
specifically inhibit reverse transcriptase.
Fresh berries are hard to come by this
time of year, but until next summer rolls
around, you can give your companion’s
health a boost by adding a few frozen
raspberries, blackberries and blueberries
to his diet. Try to look for organicallygrown
produce wherever possible. You
can also find dried raspberry powder at
many health food stores – dosage will
vary depending on your animal so it’s
best to consult with a holistic vet first.
With so much going for them, the
raspberry and its cousins make an
excellent addition to your furry friend’s
diet – and yours!
Diabetes and
ellagic acid
Cancer isn’t the only prevalent
disease plaguing our animals.
Dogs and especially cats
also suffer in large numbers
from diabetes.
The body turns the ellagitannins
found in raspberries and other
berries into ellagic acid. New
data shows that this ellagic
acid is very effective in
preventing damage to the
eyes, kidneys, heart and the
small capillaries of the feet
that occurs with high glucose
levels. It does this by inhibiting
an enzyme called aldose
reductase. This enzyme is
responsible for the production
of protein-sugar products called
AGE (advanced glycation
end products). These end
products cause the damage
of small blood vessels that
leads to the blindness, kidney
damage, strokes, heart attacks
and loss of limbs associated
with diabetes. Along with
several other constituents in
raspberry seed powder, ellagic
acid hances insulin action,
decreases insulin resistance,
and lowers blood sugar. It also
has multiple anti-inflammatory
effects and decreases
oxidative stress as well as
blood pressure. |
What else do raspberries offer?
Besides ellagitannins, the short list of other beneficial compounds
found in red raspberries includes anthocyanins, salicylic acid, quercitin
and catechins.
1. Recent work has shown that anthocyanins are more effective than
vitamin E and equivalent to ibuprofen and naproxen in inhibiting the
Cox-1 and Cox-2 enzymes. These enzymes are associated with the pain
of arthritis and other inflammatory diseases, while Cox-2 inhibition is
positively linked to eventingbreast cancer in humans. Anthocyanins
provide many additional health benefits that include controlling diabetes,
improving circulation, aiding the retention of motor skills and preventing
the loss of memory due to aging.
2. Salicylic acid may have the same effects as aspirin in protecting
from cancer and the progression of atherosclerosis.
3. Quercitin and catechins are flavonals known to have antioxidant
benefits, including cancer prevention. Quercitin may also act as
an antihistamine.
< Previous Page
Published in
the December/January 2008 issue of Animal
Wellness |
