Eye drops to treat cataracts
Approximately 180 million people worldwide suffer from cataracts and surgery to replace the lens with a plastic one is currently the only solution.
A cataract is clouding caused by proteins in the eye lens forming clumps. This clouding scatters light, so the sufferer cannot see properly.
If surgery can't be accessed the condition causes blindness, leaving a legacy of 20 million people globally who are blind and will remain that way because they have no way of getting treatment.
But there could be a new option in the future. A study showing cataract formation is reversible in mice has been published in Science this week.
In a healthy eye, proteins are kept apart by aptly named chaperones, stopping the clumping that causes cataract formation.
The group discovered that a series of small molecules called sterols, similar to cholesterol, can stabilise these chaperones. When applied as eye drops to mice with cataracts, the sterols reduced the cloudiness of the lens.
These small molecules could also help treat the condition presbyopia, thought to be the first stage in age-related cataract formation.
And it's not just mice who benefit from this treatment, these results back up a similar study that saw improvements in the transparency of cataracts in dogs when they were treated using sterol eye drops, published in Nature in July.
''The really quite exciting aspect to these discoveries is that they used completely different approaches'' explains Roy Quinlan from Durham University, whose perspectives paper was published alongside the study in Science this week.
The Nature paper studied a family with an inherited form of cataract, and noticed that lanosterol (a precursor to cholesterol) was limited. When they put lanosterol into eye drops to treat dogs with the condition ''remarkable things happened in the lens'' says Quinlan.
Previously, cataract formation was always thought to be an end point, but these studies offer the opportunity for it to be delayed or reversed.
If a treatment using eye drops was developed, ''we don't then have to rely on surgery,'' bringing hope to the millions of sufferers around the world who currently cannot access surgical treatment.