Tuesday, July 6, 2010

Eye believe: resveratrol may prevent blindness

Here’s a word that you should know: angiogenesis. Sounds like a cover of a classic Rolling Stones song by Phil Collins’ former band, but what it refers to is the growth of new blood vessels. Sometimes this is a good thing, sometimes not. In the case of some causes of blindness, abnormal angiogenesis is a very bad thing indeed.

Resveratrol, the superstar molecule from red wine, has long been known to inhibit angiogenesis. This may be one of the reasons why it fights cancer, since tumors rely on ingrowth of new blood vessels in order to expand. Abnormal angiogenesis is also involved in some causes of age-related blindness such as diabetic retinopathy and macular degeneration, conditions affecting thousands each year. A recent study suggests that resveratrol’s ability to inhibit angiogenesis might help to save eyesight for many.

Like many such studies, this one was done in mice. These poor subjects had laser treatments to destroy some of the blood vessels in their retinas. Normally, the body would respond by sending signals to stimulate angiogenesis in order to restore the blood flow to the injured eyes, but resveratrol was noted to interfere with this process through specific molecular interactions that the research team was able to decipher. The implication was that protection against disorders related to abnormal angiogenesis might be achieved with resveratrol, though it is important to note that there is a lot to prove in order to apply it in humans.

One case study reported last year did provide some encouragement that oral supplementation with resveratrol might be able to help eyesight. The subject was an 80 year old man with progressively worsening night blindness, despite taking extra lutein and omega-3 fatty acids. This was correlated with deposits of a material called lipofuscin, a substance correlated with age-related loss of vision, in the retina. After 5 months of taking oral supplements containing resveratrol and other wine polyphenols, the subject’s vision improved by objective measurements and the lipofuscin deposits correspondingly decreased. While a case report lacks the heft of an actual clinical trial, it does suggest a potentially fruitful avenue of further research.

There are several other reports demonstrating the protective effects of resveratrol and wine polyphenols against oxidative damage and chemical toxicity of retinal cells, and even some benefits on inhibiting cataract formation. Wine appears to be unique among alcoholic beverage consumption in protecting against cataracts, which implies a role for the polyphenol antioxidants. I’ll keep an eye on the topic for you.



Khan AA, Dace DS, Ryazanov AG, Kelly J, Apte RS. Resveratrol Regulates Pathologic Angiogenesis by a Eukaryotic Elongation Factor-2 Kinase-Regulated Pathway. Am J Pathol. 2010 May 14. [Epub ahead of print]


Richer S, Stiles W, Thomas C. Molecular medicine in ophthalmic care. Optometry. 2009 Dec;80(12):695-701.

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