New Study Shows Potential Alternative Treatment for Wet AMD
Introduction
A team of researchers at Ohio State University have discovered a potential alternative treatment for wet age-related macular degeneration (AMD), the leading cause of blindness among the elderly in developed countries. The study, published in Science Direct, has identified an enzyme related to cell growth and division as the culprit responsible for abnormal vascular growth that causes blurred central vision in wet AMD. The enzyme, called telomerase, was successfully targeted with an experimental drug that suppressed abnormal vascular growth in the animal’s retina. Currently, the only treatment for wet AMD is an anti-VEGF injection into the eye which after two years, about half of people stop responding and patients can develop scarring under the retina. The need for better treatments for wet AMD is clear, and the potential of this new study suggests that newer targets need to be tested.
The Difference Between Dry and Wet AMD
Dry age-related macular degeneration constitutes about 80% of all AMD cases, and occurs when the macula, a part of the retina, gets thinner, leading to the build-up of proteins and cell death that blur a person’s central vision. Wet AMD, also known as neovascular AMD, is caused by the growth of new blood vessels that invade the retina, a space normally free of vascular activity. Blood vessels that invade are often not healthy, they leak their contents, and cause inflammation that can lead to blindness.
The Role of Telomerase in Wet AMD
Researchers from Ohio State University found that in mice, telomerase, an enzyme that has been associated with rapid production and migration of cells lining blood vessels, can have a similar damaging effect in the retina. The enzyme stimulates the production of VEGF, which in turn, increases blood supply to the area and can accelerate the growth of new blood vessels in the retina, leading to blurred central vision. Choroidal neovascularization (CNV) is the principal driver of blindness in neovascular AMD. Increased activity of telomerase has been associated with endothelial cell proliferation, survival, migration, and invasion in the context of tumor angiogenesis. In the study, researchers confirmed that gene expression and activity of telomerase in mice demonstrated a direct correlation with CNV, and that genetic deficiency of the telomerase components, telomerase reverse transcriptase (Tert) and telomerase RNA component (Terc) suppressed laser-induced CNV in mice.
The Results of the Study
The researchers tested the effects of an experimental compound that inhibits telomerase activity. By doing this, they were able to demonstrate that the drug lowered telomerase activity in healthy mice and injected it into the eyes of mice with symptoms of wet AMD. They found that it significantly reduced the abnormal blood vessel invasion similar to the current anti-VEGF treatment, and when tested at lower doses, the combination of both drugs gave the best results. “Possibly, one goal would be using a combination therapy rather than one alone,” said senior study author Nagaraj Kerur, DVM, PhD, associate professor of Ophthalmology and Visual Sciences at the Ohio State University College of Medicine. “But telomerase inhibition by itself can also be pursued independently, and that is the plan.”
Conclusion
This study offers hope for those affected by wet AMD and the development of alternative treatments. Even though this research was conducted on mice, it is a promising step in the right direction. The use of this experimental drug, and the potential for combination therapy, could pave the way for researchers to test a new target for future wet AMD treatments. This work was supported by National Institutes of Health grants, the Ohio Lions Eye Research Foundation, and a Research to Prevent Blindness grant.
Long-tail Keywords:
- Wet AMD alternative treatment
- New AMD treatments
- Telomerase activity in AMD
- Wet AMD research developments
- Experimental AMD treatments
Originally Post From https://www.ophthalmologytimes.com/view/study-zeroes-in-on-new-target-for-treatment-of-one-type-of-macular-degeneration
Read more about this topic at
Blurred Vision: Symptoms, Causes & Treatments
Blurred Vision: Causes, Diagnosis, and Treatment