New Hope for Cataracts
by Ward Dean, MD (VRN, November 2003)

A nuclear cataract, the most common type, is caused by the clumping of lens proteins called crystallins. Scientists attribute the clumping to glycation, a chemical process in which sugar-protein complexes become crosslinked, causing cellular degradation which promotes aging. Recent studies have shown that carnosine defends the body against glycation and can restore the proteins in the lens by removing cross-linked carbonyl groups. In addition, carnosine reduces intraocular pressure by functioning as a water pump on a molecular level.

Both carnosine and N-acetylcarnosine are found throughout the human body, but carnosine is not as soluble in lipids as N-acetylcarnosine, which is soluble in both fats and water, and can, therefore, pass more easily through the lipid membranes of the corneal and lens cells and into the cell interior, where it gradually breaks down into carnosine.

When Russian scientists conducted double-blind, placebo-controlled trials on 49 older adults who had cataracts, the researchers found that eyes treated with N-acetylcarnosine eye drops improved over a course of 6 months and none deteriorated; whereas, untreated eyes worsened. When the same researchers, studied another group of subjects who had some vision problems, but not obvious cataracts, the investigators found that the eye drops alleviated eye tiredness and improved clarity of vision. These studies suggest that carnosine and N-acetylcarnosine eye drops may prevent and safely treat cataracts without surgery.