Three Important Recent Research Findings Shed New Light on Age-Related Macular Degeneration (AMD)

Serious Visual Side Effects Found With New AMDare likely to affect the aging populations, AMD
Treatmentranked lowest in the list.
A study in the August 2008 New England JournalThe AMDAI spoke for the necessity of increased
of Medicine (NEJM) suggested that Dry AMD--aunderstanding about AMD. In the web document
form of Age-related Macular Degeneration (AMD)related to the study, the chair of the organization
found in eight to nine million Americans--may beDavid Herman says, "This study clearly indicates
associated with a gene in our body. The studythat there is a low level of concern about AMD
also found that in individuals with this geneticand many people aren't seeking adequate eye
variation, a currently practiced modern treatmentcare until the disease has reached more of an
for AMD may lead to serious adverseadvanced stage." As antioxidants help keep the
consequences, including blindness.eyes healthy (for example, by cutting the risk and
Researcher Kang Zhang and co-workers from theslowing the progress of AMD)--regular intake of
Shiley Eye Center at the University of California,antioxidant-rich nutritional supplements may be of
San Diego, found that a key protein that alertssome practical help for people who avoid visit an
our immune system to the presence of viraleye doctor at regular intervals.
infections--called Toll-like Receptor 3 (TLR3)--wasMore Support for Biochemistry of Antioxidants in
linked with dry AMD. Zhang and co-workers alsothe Treatment of AMD
noted that if individuals with a genetic variant ofThe Journal of Biological Chemistry (JBC), has
TLR3 are treated with a modern treatment forreconfirmed that antioxidants substantially help
AMD--called RNA interference (RNAi)--they couldcombat AMD in a study published on September
be at risk for serious adverse effects, including9, 2008.
blindness. RNAi is a modern modality of treatmentThe study showed two damaging processes in
that is used to silence the genes related toretina that play an important role in the
various disease conditions.development of AMD. Conducted by researchers
The study links the occurrence of dry AMD withfrom Brigham Young University (BYU) and Cornell
a genetic variation of TLR3, which indicates thatUniversity, the research also found that
some persons with this particular genetic variationantioxidants fight against AMD by significantly
will be more prone to develop dry AMD. Givendisrupting the link between those two processes
that gene test is emerging as a new trend in(in retina) and extending the lifetime of the
personal health, genetic linkage of dry AMD mayirreplaceable photoreceptors and other cells in
help people know--through gene tests--whetherretina. "The implication is that people at risk of
they've propensity for the disease. And this inmacular degeneration could help prevent the
turn may help them adopt proper preventivedisease by consuming antioxidants," says, in a
measures to stay away from the disease. Thenews release, Heidi Vollmer-Snarr, co-author of
second component of the study has raised thethe study and a chemist at the BYU.
question of safety in adopting modern treatmentsThe authors explained the role that antioxidants
for AMD. It has cited the evidence that a newplay in tackling AMD. In the study, the researchers
treatment approach for AMD--RNAi--may lead tolooked at a compound called A2E (which is a
serious adverse consequences, including blindness.byproduct of natural cellular activity) and damage
This finding has reinforced the position ofto mitochondria (the power plants present inside
nutritional treatment in AMD, because treatmentthe cells). The researchers found that when
of AMD with nutritional supplements is safe andoxidative stress is created on A2E, by light
substantially effective.exposure, it disrupts the energy production in
Elderly People Remain in the Dark Aboutmitochondria. It results a shortage of energy
Age-Related Macular Degenerationinside the cells which in turn hampers the daily
Research released this month by thecleaning and maintenance of photoreceptors and
Toronto-based AMD Alliance International (AMDAI)other type of retinal cells. "The result is more A2E
showed that AMD ranked lowest among a list ofbuildup, and the cycle of destruction hastens the
conditions that are likely to affect the agingdeath of these vital visual cells, which are not
population, when participants in that study werereplaced when they die," says a BYU news
asked how much they know about thoserelease associated with the study, adding, "The
conditions.experiments performed with visual cells from
This study suggested that people lack knowledgerats, cows and humans showed that antioxidants
and concern regarding AMD, and it is preventingcould completely counter the damage." Regarding
them from taking critical steps to halt or slow thethe role of antioxidants in AMD, research in past
progression of the disease. According to thesuggested that antioxidants found in nutritional
study, amid those who had a high propensity forsupplements (for example, Lutein, Zeaxanthin,
loss of vision due to AMD, only 56 percent of theVitamin E and beta-carotene) work as scavengers
participants met an eye specialist once a year andfor free radicals and protect the retina against
more. That apart, when the participants weredamages caused by oxidative stress.
asked about their knowledge about conditions that