• Kayla Hui

Melt Away Cataract Treatments

Millions of people are impacted by cataracts each year. By the age of 75, it is predicted that approximately half of all Americans will have cataracts. A cataract is a clouding of the lens of the eye that causes people to see through cloudy lenses. The effects of a cataract can be compared to a person looking through a frosty/foggy window. Cataracts result in difficulties to read, drive a car, or view the expressions of others.

Cataracts are caused by aging or injury that can change the tissue of your eye’s lens. Some people may also be predisposed to cataracts due to inherited genetic disorders. Cataracts may also be caused by other eye conditions, past eye surgery, or certain medical conditions such as diabetes. As you age the lenses in your eyes, the part of your eye that focuses the light becomes less flexible, thicker, and less transparent.

Age-related and other medical conditions may cause the tissues within the lens to break down, clumping them together. This results in a slight clouding of small areas within the lens. After this stage, the cataract begins to develop into a denser and bigger part of the lens. The cataract will also scatter and block more of the light that passes through your lens. This lack of focus of light reaching your retina is what results in blurred vision.

The only current treatment available for cataracts is cataract surgery. During cataract surgery, the clouded lens is removed then replaced with a clear, artificial lens known as an intraocular lens. Currently, this procedure, while relatively safe, does pose certain risks of infections or even retinal detachment. Cataract surgery also presents a high cost in areas where financial resources and medical facilities are limited. Due to these issues scientists have developed an eye drop that can shrink down and dissolve cataracts. Pharmacological therapy could also be used for prevention and treatment which will make cataract treatment a lower economic burden and more widely available. Pharmacological therapy will also significantly reduce the need for possibly invasive cataract surgery.

The meltaway cataract treatment is based on crystallins. Crystallins are proteins that are misfolded and clumped together during the formation of cataracts. This is important because crystallins are a major component of fiber cells that form the eyes’ lenses. The clumped-together proteins are called amyloids.

In a new study, led by Leah N. Makley, Ph.D., and Kathryn McMenimen, Ph.D., it was found that properly folded crystallins and their amyloid forms have a key difference. The difference being that amyloids are much harder to melt. Using this information a team at the Life Sciences Institute’s Center for Chemical Genomic used HT-DSF, high throughput differential scanning fluorimetry, to apply heat to amyloids while applying thousands of chemical compounds. For clarification, HT-DSF proteins emit light when they reach their melting point.

Using this eventually the research group was able to focus on 12 compounds that are part of the chemical class of sterols. This pharmacological substance was lanosterol, and it is predicted to reverse lens opacity by dissolving the aggregation of the crystallin proteins.

In 2015 lanosterol and hydroxycholesterol were thought to restore vision by binding to the crystallin chaperone protein to dissolve cataracts.

However, a more recent paper posted in 2019 by researchers at the University of Nebraska Medical Center suggests that lanosterols have failed to restore lens clarity. But it still has not been clarified whether or not lanosterol is effective as a treatment for cataracts. Yet again, there is an even more recent paper from 2020 that directly contradicts this claim. So at this time, it is slightly ambiguous on the efficacy of lanosterol eye drops as a treatment for cataracts. However, if lanosterol were able to treat cataracts or significantly reduce cataract development would present a much lower cost than cataract surgery. Lanosterol eye drops also present it as a safe, non-invasive alternative for more moderate forms of cataracts.

Although lanosterol eye drops were the most prominent, due to the evidence of them working well in a cataractous dog, there are also various innovations being made in the field of pharmacological therapy. At this time there is also the oxidative/antioxidative system, along with the anti-aldose reductase. Regardless of the efficacy of lanosterol eye drops it is hopeful that in the coming years' pharmacological therapy is used as a treatment for cataracts in place of cataract surgery.