Cloudy eyes caused by protein imbalance, discovery may lead to new cataracts treatment

MUNICH, Germany — For anyone that’s thought they were walking in a fog, only to figure out their eyes were the problem, a new study is finally providing some clear answers. Researchers in Germany say a protein imbalance is to blame for cloudy eyes. While it may sound like a minor problem, the discovery is giving new insight into what leads to cataracts and may help create a new treatment that doesn’t involve surgery.

Cataracts is the most common eye condition among humans. While scientists don’t exactly know how the ailment begins, the results leave patients with clouding in the lens of their eye. A team from the Technical University of Munich (TUM) finds that the balance of protein solution in these lenses plays a major role in whether clouds begin to form.

“When the balance of the proteins in the lens is destroyed, they clump together and the lens becomes cloudy,” says Professor Johannes Buchner of the Chair of Biotechnology at TUM in a university release.

Cloudy eyes can have several causes

While the result of eye clouding is cataracts, researchers say this condition has multiple causes. Since these proteins form in the embryo and can not be replaced, damage to this solution can build up over time. This is one of the main reasons cataracts typically strikes older adults.

However, some patients have a genetic vulnerability to developing eye problems. In these patients, the protein in their lenses mutate and clouding can begin during childhood or even younger.

Study authors examined mice dealing with a hereditary form of cataracts. Until this report, scientists believed only defective proteins in the eye reacted with each other to form clumps. Buchner’s team revealed that this is not the case in mice with “genetic cataracts.”

“We discovered that the mutated, unstable proteins in the lens were not there,” Buchner explains. “They are eliminated immediately.”

Instead of defective eye proteins clumping together to form clouds, the study finds it’s actually the “healthy” proteins which are now out of balance that clump together to impair vision.

“Our model, based on these new insights, says that the balance between the various proteins, or their ratios to one another, is important. When one of these components is missing, the remaining ones interact and form clumps.”

Creating an alternative to cataract surgery?

Unfortunately for most patients with severe cataracts, the only treatment option is surgery. If the lens is too cloudy to see out of, doctors will surgically replace the lens with an artificial one.

The new study is giving scientists a clearer perspective on vision loss. Buchner adds that there has never “been such a comprehensive investigation of the lenses in mice, comparing wild populations and mutants.”

Due to the findings, researchers are hopeful they can create a new method of treating the protein imbalance without removing the patient’s lenses.

“If you understand exactly what is happening, you can also think about ways that might use medication to disrupt the bad interactions,” Buchner concludes. “But we have a long way to go – and first we need to show that the proposed model also applies to the lens in the human eye.”

The study appears in the journal Nature Structural & Molecular Biology.