Their findings, available in the Proceedings of the National Academy of Sciences, suggest a potential strategy to treat age-related macular degeneration (AMD), a vascular eye disorder that affects nearly 2 million Americans and is a leading cause of blindness among older people.
"MicroRNAs can affect multiple pathways involved in age-related macular degeneration," said Dr. Shusheng Wang, assistant professor of ophthalmology and pharmacology and co-senior author of the study. "Therapeutic manipulation of microRNAs 23 and 27 may give us a way to treat choroidal neovascularization in patients with degenerative retinal diseases."
In the study, researchers found that silencing the microRNA cluster members miR-23 and miR-27 hindered the excessive formation of blood vessels in the back of the eye, known as choroidal neovascularization. When these blood vessels hemorrhage and leak, it creates a sudden deterioration of central vision.
MicroRNAs are tiny pieces of genetic material that can target multiple components of signaling pathways. By interacting with other protein-making molecules in cells, they help fine-tune the expression of networks of genes and control cell function.
But microRNAs also can contribute to the excessive blood vessel formation that is responsible for vascular disorders, the current UT Southwestern study shows. That's because they stimulate the growth of new blood vessels from pre-existing vessels, a process called angiogenesis, which is an important natural process in the body used for healing and reproduction.
The body usually controls angiogenesis through a precise balance of growth and inhibitory factors in healthy tissues, Dr. Wang said. When the process becomes imbalanced, however, increased angiogenesis can lead to a variety of debilitating conditions.
Previous treatments for degenerative eye disorders have focused on inhibiting vascular endothelial growth factor (VEGF), a secreted protein that stimulates blood vessel formation. VEGF has been known to be a contributing factor in vascular disease in the retina of the eye.
Anti-VEGF drugs, which are injected into the eyeball, have been used to give patients some improvement in vision. These drugs, however, have limited effectiveness in treating some forms of neovascular AMD, and also have potential side effects.
Dr. Wang said further research may show that other microRNAs might also be involved, and that targeting multiple pathways may provide benefits in the treatment of these diseases.
"We want to see if a combination of microRNAs and angiogenetic drugs have a synergetic effect on the progression of macular degeneration," Dr. Wang said.
Dr. Eric Olson, chairman of molecular biology, was the study's other co-senior author. Other UT Southwestern researchers involved were Dr. Rafael Ufret-Vincenty, assistant professor of ophthalmology, Dr. Qinbo Zhou, postdoctoral fellow and lead author; Rachel Gallagher, research technician; and Dr. Xinyu Li, a visiting professor.
The study was supported by a startup fund from the Department of Ophthalmology and grants from the National Institutes of Health and from the Research to Prevent Blindness Foundation.
Visit http://www.utsouthwestern.org/ophth to learn more about UT Southwestern's clinical services in ophthalmology.
This news release is available on our World Wide Web home page at http://www.utsouthwestern.edu/home/news/index.html
To automatically receive news releases from UT Southwestern via email, subscribe at www.utsouthwestern.edu/receivenews
Robin Russell | EurekAlert!
New application for acoustics helps estimate marine life populations
16.01.2018 | University of California - San Diego
Unexpected environmental source of methane discovered
16.01.2018 | University of Washington Health Sciences/UW Medicine
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
16.01.2018 | Materials Sciences
16.01.2018 | Materials Sciences
16.01.2018 | Power and Electrical Engineering