Researchers at Anglia Ruskin University (ARU) in the UK have made significant progress in treating cataracts with a drug compound, paving the way for new treatment methods, a university press release said.
A cataract is a medical condition where the lens of the eye becomes cloudy over time and affects the quality of vision. The opacity occurs due to the dysregulation of the proteins in the lens. This eventually causes them to clump, scattering light away from the retina, thus reducing vision. According to estimates by the World Health Organization (WHO), the condition affects approximately 65 million people globally, with moderate to severe vision loss in about 80 percent of cases.
Use of medicine as treatment
Traditionally, surgery has been the only treatment for this condition. A team of researchers led by Professor Barbara Percionic at ARU conducted advanced testing of oxysterol as an anti-cataract drug. Oxysterol is a derivative of cholesterol that plays a role in many cellular functions, including autophagy – the degradation of conserved cells to remove unnecessary components.
The compound called VP1-001, when used in laboratory experiments, showed a significant improvement in the refractive index profile for 61 percent of cases. In comparison, the press release stated that lens opacity was reduced in 46 percent of cases. The refractive index profile is a critical parameter in determining the focusing ability of an eye. So the drug works to restore the organization of the protein inside the lens.
“It is the first research of this kind in the world,” Professor Percionic said in the press release. “The compound’s positive effects have been suggested as an anti-cataract drug but have not previously been tested on lens optics. It is an important step forward toward treating this very common condition with medication rather than surgery.”
However, studies have also shown improvement in only some but not all types of cataracts. This means that treatment will only be an option for certain types of cataracts, and a distinction must be made during the development of future anti-cataract drugs, the researchers said.
The study was published in the journal, Ophthalmology and visual sciences.
destination: To investigate how cataract-related mutations affect the gradient refractive index (GRIN) and lens opacity in mouse lenses and whether there is any effect on lens optics from treatment with oxysterol complex.
Techniques: A total of 35 mice including wild-type and knockout mutants (cry-R49C and crying-R120G) In these experiments: 26 mice treated with VP1-001 topical, oxysterol, in one eye and vehicle in the other, and nine mice were untreated. Slit-lamp biomicroscopy has been used to analyze the lens in live animals and provide grades of apparent cataracts. The refractive index in the lenses of 64 whole, unfixed mouse eyes was calculated from measurements using X-ray tomography based on Talbot X-ray measurement with a synchrotron radiation source.
consequences: Heterozygous cryR49C lenses have slightly irregularly shaped contours in the center of the GRIN and pronounced GDI perturbations at the anterior and posterior poles. Curves near the lens surface were more intense in homozygous cryingR120G lenses. VP1-001 topical treatment, oxysterol, demonstrated an improvement in refractive index profiles in 61% of the lenses and this was supported by a 1.0 reduction in apparent lens opacity in 46% of live mice.
Conclusions: These results indicate that α-crystallin mutations alter the refractive index gradient of mouse lenses in distinct ways and suggest that topical treatment with VP1-001 may improve lens transparency and refractive index lines in some lenses with mutations.