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It Takes Vision to Say, “I See You”
Can Age-Related Macular
Degeneration Be Prevented?
A frontal assault with a broad spectrum of
eye-healthy nutrients may be the way to go
By Will Block
n Microsoft Windows, one of the built-in
screen savers is “3D Pipes,” in which pipes of different colors rapidly grow into
a right-angled, crazy-quilt network that looks like a petroleum refinery on LSD.
Check it out—it’s fun! While amusing yourself by watching that, try to imagine a
similar process occurring—on a tiny scale and much more slowly—inside your eyeballs.
This is no joke. Such a thing can happen (pray that it does not happen to
you). It involves the growth of an irregular network of new blood vessels where
they do not belong—beneath the retina, at a small, yellowish spot called the macula.
The macula, located in the center of the retina, near the optic nerve (where the
“blind spot” is), is responsible for your so-called central vision—the vision that
allows you to see fine details clearly. Your overall vision allows you to see that
you’re holding a magazine in your hands right now, but it’s your central vision
that allows you to see and recognize the words you’re reading. Central vision also
allows you to watch TV, drive a car, fix a leak, sew a button, cut your fingernails,
and countless other things that require you to discern the details of the objects
you’re looking at.
If You Should Get AMD, Try to Stay Dry . . .
Normal vision
Age-related macular degeneration
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You surely don’t want to lose your central vision—but you could if you were unlucky
enough to be afflicted with age-related macular degeneration (AMD), a slowly
progressing neurodegenerative disease for which there are few treatments and no
cure. But what causes the macula to degenerate? We don’t know the cause, but we
do know how the process occurs. There are two processes, actually, leading to the
two different forms of AMD, called dry and wet (doctors, of course,
have fancier terms than that: atrophic and neovascular).
In dry AMD, the problem is the formation—slowly, painlessly, asymptomatically—of
small, yellowish, fatty deposits called drusen in one of the deepest layers
of the retina. They can form in one eye or both, and the process can take years.
As the drusen grow in number and size, the patient’s retinal function is degraded,
causing blind spots to appear (so to speak) in the visual field, and color perception
is diminished. About 85–90% of all cases of AMD are of the dry type.
As dry AMD progresses to an advanced stage, there is an increasing chance—up to
43% in one study—that it will turn into
the much more dangerous wet AMD within 5 years. Wet AMD accounts for the remaining
10–15% of cases, but it causes about 90% of all cases of legal blindness from AMD.
It can also occur all by itself, often with alarming speed: it can develop in a
matter of weeks or even days, and it’s dangerously painless. Any sudden change in
your vision should send you running to your ophthalmologist—don’t waste precious
time!
. . . Because Wet Is Much More Serious
In wet AMD, a network of invasive blood vessels develops beneath the retina in the
area of the macula. As the abnormally fragile vessels grow, they leak blood or fluid
into the retina, which can separate and lift, somewhat like a blister, causing distortion
in the visual field. Worse yet, retinal cells are degraded or killed, and the damage
done to the macula can lead to scarring and central blindness.
The process is called neovascularization (“new vessel formation”), defined
as the proliferation of blood vessels in tissues not normally containing them, or
the proliferation of blood vessels of a different kind than usual for the tissue
in question. Either way, it’s a bad thing. Neovascularization is a special case
of the broader phenomenon of angiogenesis, which is the growth of new blood
vessels. Angiogenesis is beneficial when it occurs in wound healing, e.g., but harmful
when it occurs in tumors, where it spawns blood vessels needed for the cancer’s
continued growth. And it’s harmful, obviously, when it leads to wet AMD.*
Know Your Risk Factors
© iStockphoto.com/Darren Hubley
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In the industrialized world, age-related macular degeneration is the leading cause
of irreversible blindness in people over the age of 55. In the United States alone,
AMD currently affects some 10 million men and women. Mercifully, it does not cause
total blindness—it causes central blindness, leaving peripheral vision more or less
intact (but it’s blurry). Often, that’s enough for the victim to be declared legally
blind.
Although the cause of AMD is unknown, the risk factors are known. The main
ones are being old, being white, having a family history of the disease, being or
having been a smoker, and having a low dietary intake of antioxidants. Additional
factors are being female, having fair skin, having light-colored eyes (because they’re
more likely to be damaged by solar ultraviolet radiation), having high blood pressure,
and being overweight or obese.
Antioxidants Are Vitally Important
In the last few decades, it has become increasingly apparent that dietary antioxidants
play a vital role in maintaining and optimizing countless aspects of our health,
including that of our eyes, and there is now a vast body of scientific literature
supporting that belief. Among the most well studied nutrients for eye health are
the antioxidants vitamin C, vitamin E, and beta-carotene (a vitamin
A precursor), and the mineral zinc. In the 1990s, a large epidemiological
study called The Rotterdam Study, conducted in the Netherlands, saw a 35% risk reduction
for AMD in subjects who had an above-median daily intake of these four nutrients.
There are many more nutrients, however, with documented ocular benefits. Among the
most important are the antioxidant carotenoids lutein and zeaxanthin,
which are found in many fruits and vegetables. They’re responsible for the yellow
color of the macula, where they’re found in high concentration. Two other nutrients
of special importance are the antioxidant polyphenols curcumin, which comes
from turmeric, and EGCG (epigallocatechin gallate), which is found in green
tea. These compounds are known to be effective inhibitors of angiogenesis, thus
making them attractive candidates for use against wet AMD. In next month’s issue,
we will report on all these compounds in some detail.
The Trager Formulation
In the 1980s, Dr. Seymour F. Trager (see the sidebar below) and his colleagues developed
and tested a nutrient formulation for the prevention of wet AMD.
It consisted of the following 19 active ingredients (in decreasing order of amount),
all of which they had tested individually for efficacy: curcumin (an anti-inflammatory,
antioxidant polyphenol); EGCG (an anticarcinogenic, antioxidant polyphenol);
vitamin C; taurine (an aminosulfonic acid); vitamin E (as d-alpha-tocopherol);
N-acetylcarnosine (a dipeptide derivative); bilberry extract
(containing antioxidant anthocyanidins); resveratrol (the life-extending
antioxidant polyphenol from red wine); zinc; superoxide dismutase (SOD, an
antioxidant enzyme); α-lipoic acid (an exceptionally versatile antioxidant
fatty acid); lutein (an antioxidant carotenoid); beta-carotene; lycopene
(an antioxidant carotenoid); zeaxanthin (an antioxidant carotenoid); copper;
riboflavin (vitamin B2); catalase
(an antioxidant enzyme); and selenium.
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An Interview with Dr.
Seymour F. Trager
Seymour F. Trager, Ph.D., Sc.D. (Hon.), is a physiologist who has spent a lifetime
studying problems associated with vision and hearing. Now retired, he maintains
an active interest in the formulation of therapeutic products based on natural substances.
LE: Please tell us a little about your professional background.
Dr. Trager: I received my education, including a Ph.D. in physiology, through
the Armed Services Training Programs when I served in the U.S. Air Force. My professional
career spanned over 40 years in pharmaceutical company management and R&D. I served
as President and CEO of IRC (International Research Consultants), a company involved
in new drug development. That work led to numerous U.S. and foreign patents. Along
the way, I became a member of many professional societies devoted to solving human
vision problems.
LE: What led to your interest in creating a nutritional product for age-related
macular degeneration?
 Dr.
Trager: Most of my postgraduate studies and professional work had to do
with ophthalmic science (although I also devoted a great deal of effort to the study
of auditory problems, especially tinnitus). Being so involved in that field, it
was natural that I should direct my product development research toward diseases
of the eye. AMD is among the worst—it’s a leading cause of blindness for people
over 50 years of age. About 25 to 30 million people worldwide are afflicted in some
way with this condition. With that in mind, I aggressively sought scientific advances
for the prevention and treatment of AMD.
LE: When did you conduct the rabbit study [described in the accompanying
article]?
Dr. Trager: That was done during the 1980s, when my colleagues and I were
studying the possible benefits of various nutrients—vitamins, minerals, carotenoids,
polyphenols, herbal extracts, etc.—for protecting against AMD, particularly wet
AMD, the most destructive form of the disease. It wasn’t until the 1980s that scientists
began to see the connection between AMD nutritional deficiencies, particularly with
regard to the body’s antioxidant status. The research we did was not published,
by the way, because we needed to hold it proprietary for commercial purposes.
LE: What is the role of the transport materials included in your formulation?
Dr. Trager: Certain substances are known to facilitate the transport of various
types of nutrients across the cellular barriers they encounter on their long journey
from your mouth to wherever it is your body needs them—in this case, the retinas
of your eyes. That’s important because nutrients can’t do you any good unless they
get to the organs or tissues that need them. We devoted a lot of effort to testing
the efficacy of transport agents for that purpose, and the ones we included in the
formulation seemed to work well.
LE: What are the special benefits of your formulation?
Dr. Trager: I think the main advantage is that it’s so multifaceted, bringing
together a great variety of ingredients, all of which are known to benefit the eyes
in one way or another. It includes, of course, the four ingredients (vitamins C
and E, beta-carotene, and zinc) from the well-known Rotterdam Study, which in the
1990s established the long-term preventive value of those nutrients against AMD
in elderly people in the Netherlands.
Our formulation goes much further than that, however. Of particular importance with
regard to wet AMD is the inclusion of two compounds known from animal studies to
inhibit angiogenesis: curcumin (from turmeric) and EGCG (from green tea). If you
could prevent angiogenesis in the retina, you could prevent wet AMD, and that would
be terrific. I think it’s worth trying any substance that shows evidence of efficacy—provided,
of course, that it’s safe, as all the ingredients in our formulation are.
In our human screening tests, there were no reports of toxicity. Although our test
population was small, and the protocol was not double-blind, the results were encouraging:
we received subjective reports of better color discrimination, and ophthalmological
examinations of a few patients showed improvements of one to two lines in the familiar,
doctor’s-office Snellen test for visual acuity.
Now let me brag a bit. I’ve been taking most of the ingredients in our formulation
for many years (by using a combination of available supplements), and at age 83,
I still don’t need glasses for distance or reading. Not bad!
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The formulation also contained four ingredients for improving the bioavailability
of the others: pectin (a water-soluble, colloidal carbohydrate, acid-modified
for greater absorption); proline (an amino acid); Ultralec
P (a commercial lecithin product); and Bioperine
(a commercial black pepper extract consisting largely of piperine).
The Rabbit Study
As part of a larger research program, Dr. Trager and his colleagues conducted a
study on rabbits to test the formulation’s efficacy against neovascularization. In this study, the neovascularization was
not in the retinas of the rabbits’ eyes, but in their corneas, where it could be
induced experimentally. Using high-frequency radio waves, the researchers created
small lesions (“burns”), about 1 mm in diameter, on the corneal surface of the anesthetized
rabbits’ eyes.
Twelve healthy albino rabbits were used. The treatment consisted of either the “test
formula” described above or a “basic formula” consisting of six ingredients: vitamin
C, vitamin E, beta-carotene, bilberry extract, zinc, and copper (all of which were
also in the test formula, albeit in smaller amounts except for the bilberry extract,
of which more was used). These formulas were added to the rabbits’ daily chow.
 The
rabbits were divided into four groups of three each. Group 1 was fed the test formula
for 7 days; they were then anesthetized and subjected to corneal lesions. They remained
on the test formula for the next 10 days. Group 2 was treated similarly, but with
the basic formula instead of the test formula. Group 3 was lesioned but received
no treatment. Group 4 received neither lesions nor treatment. The Groups 1, 2, and
3 rabbits were killed on post-lesion days 10, 10, and 7, respectively, so that their
eyes could be examined microscopically (the Group 4 rabbits were killed for the
same purpose).
The Eyes Were Normal
Naturally, the Group 4 eyes were normal, providing the necessary standard for comparison.
The Group 3 eyes showed evidence of corneal neovascularization, i.e., invasion of
the damaged corneas by delicate new blood vessels, accompanied by some superficial
scarring and inflammation; this process began 1 to 2 days after the lesioning and
was complete by day 7. The Group 2 eyes (basic formula) showed the same signs as
in Group 3, but to a lesser extent, indicating a protective action. Finally, the
Group 1 eyes (test formula) looked surprisingly good: there was no evidence of neovascularization
when compared with the Group 4 eyes, nor was there any evidence of scarring or inflammation.
The eyes were normal.
It must be emphasized that this study involved rabbit corneas, not human retinas,
and the damage was artificially produced, not spontaneously occurring. Thus it’s
impossible to say what the effects might be in cases of wet AMD. The results, however,
were encouraging, so the researchers tried the formula on eight human volunteers
with advanced AMD (six dry, two wet), who were instructed to take two capsules before
breakfast and two more at bedtime. After two months on this regimen, there were
measurable improvements in visual acuity.
Do You See?
Look around you for a moment, and count your blessings. Number one might well be
that you can see clearly—a good start. Now all you need to do is think clearly,
as in, “I think I’ll take my precious eyesight less for granted and start doing
things to protect it from possible harm.” If it’s been too long since your last
eye checkup, make an appointment now. And while you’re at it, why not remind
your loved ones to do the same. You do love them, don’t you?
Meanwhile, think about antioxidants and the benefits they offer for protecting your
health—eyes included.
References
- Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled,
clinical trial of high-dose supplementation with vitamins C and E, beta-carotene,
and zinc for age-related macular degeneration and vision loss: AREDS Report No.
8. Arch Ophthalmol 2001;119:1417-36.
- van Leeuwen R, Boekhoorn S, Vingerling JR, Witteman JCM, Klaver CCW, Hofman A, de
Jong PTVM. Dietary intake of antioxidants and risk of age-related macular degeneration.
JAMA 2005;294:3101-7.
- Unpublished results, communicated by SF Trager, January 2007.
Will Block is the publisher and editorial director of Life Enhancement magazine.
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