New Eyedrops Could Reverse Cataracts

A newly discovered chemical could reverse cataracts, the most common cause of blindness across the world.

Around 20 million people worldwide suffer from cataracts and they're primarily an age-related condition, although they can be caused by other factors. 33% of all blindness is cataract related. 

Current treatment is effective, but it relies on surgery and for most of the developing world this is either too expensive or inaccessible; leaving millions of people without treatment. An eyedrop medication could potentially resolve these issues and treat more people worldwide. 

What are cataracts?

Fiber cells make up the bulk of the lens in your eyes, and they're largely made of proteins called crystallins. These crystallins are unfortunately very vulnerable to damage, and over time they begin to mis-fold and clump together - forming cataracts obstructing vision. 

 

"Shortly after you're born, all the fiber cells in the eye lose the ability to make new proteins, or to discard old proteins. So the crystallins you have in your eye as an adult are the same as those you're born with"

Your vision requires that these crystallins remain both flexible and transparent, and they have to be kept soluble. This job is maintained by proteins called chaperones, which surround the crystallins and make sure they stay folded correctly and don't drop out of solution and cause problems. This job is usually done quite well, but over time cataracts begin to build up in many people. 

Building on initial success

After testing 2450 compounds, a mixed American team found 12 molecules called sterols could help these clumps become soluble once more. They had initial success with a molecule called lanosterol, but this was insoluble and required an injection into the patient's eye. After additional work, the research team has found another sterol they call compound 69, which shows similar cataract melting effects but with added solubility. This means it could be applied within an eyedrop solution. In testing the compound has been effective at reducing existing cataracts and preventing them from arising in the first place. 

"If you look at an electron micrograph at the protein aggregates that cause cataracts, you'd be hard-pressed to tell them apart from those that cause Alzheimer's, Parkinson's, or Huntington's diseases. By studying cataracts we've been able to benchmark our technologies and to show by proof-of-concept that these technologies could also be used in nervous system diseases, to lead us all the way from the first idea to a drug we can test in clinical trials"

Read more at Science Daily