Featured Research

from universities, journals, and other organizations

Discovery points toward anti-inflammation treatment for blinding disease

Date:
January 18, 2010
Source:
Medical College of Georgia
Summary:
The discovery of an inflammatory mediator key to the blinding effects of diabetic retinopathy is pointing toward a potential new treatment.

Drs. Modesto Rojas (from left), Ruth Caldwell and Wenbo Zhang's research indicates that an antibody already under study to treat rheumatoid arthritis may help treat diabetic retinopathy as well.
Credit: Medical College of Georgia

The discovery of an inflammatory mediator key to the blinding effects of diabetic retinopathy is pointing toward a potential new treatment, Medical College of Georgia researchers said.

Interleukin-6, known to contribute to the debilitating joint inflammation of rheumatoid arthritis, also helps ignite inflammation of the retina, a first step in a disease that is the leading cause of blindness is working-age adults, MCG researchers reported online in Investigative Ophthalmology & Visual Science.

The finding has the scientists looking at whether an interleukin-6 antibody, which is showing success in treating rheumatoid arthritis, can halt inflammation in mice with diabetic retinopathy. "We expect that this neutralizing antibody can be used to treat diabetic retinopathy in the future," said Dr. Wenbo Zhang, assistant research scientist in MCG's Vascular Biology Center. Drs. Zhang and Modesto Rojas, senior postdoctoral fellow, are co-first authors on the paper.

Angiotensin II, a powerful constrictor of blood vessels, is typically associated with the kidneys where it plays a vital role in regulating blood pressure. The scientists suspect angiotensin II helps promotes wound healing and regulation of pressure within small blood vessels in the eye.

However in diabetes, angiotensin II levels increase in the eye -- probably in response to high glucose levels -- and help promote inflammation, spurring remodeling of blood vessels and tissue destruction, Dr. Rojas said. "Vascular inflammation is one of the first steps to inducing the changes in the retina."

MCG scientists have shown interleukin-6 is a needed accomplice whose previously undetectable levels in the eye also increase, said Dr. Ruth Caldwell, cell biologist a the Vascular Biology Center and the Charlie Norwood Veterans Affairs Medical Center and the study's corresponding author.

With the help of interleukin-6, angiotensin II induces white blood cells to stick to the endothelial cells lining blood vessels of the retina, which slows blood flow. The white blood cells also start producing inflammatory and vascular growth factors that cause blood vessel walls to leak and thicken, further constricting blood flow. Retinal cells start dying from the reduced blood and oxygen supplies that result. In response, the body prompts growth of new blood vessels, presumably to help but instead causing more vision impairment.

If the trigger, high glucose, was temporary, these natural responses might help clear damaged cells and protect the eye. "Inflammation is a compensatory mechanism that gets activated as a survival mechanism," Dr. Rojas said. "If it continues, the effect is bad."

"We have known for along time if patients keep their blood sugar under perfect control, they don't have these problems, but that's hard," Dr. Caldwell adds. "That is why it's such a difficult disease."

To examine interleukin-6's role in the destruction, the researchers injected angiotensin II into the vitreous portion of the eyes of mice missing the gene for the inflammatory factor as well as normal mice. The extra angiotensin did little to the retinal vessels of mice lacking interleukin-6 but vessels in the normal mouse retina mimicked the inflammatory reaction found in diabetic retinopathy. When they reintroduced interleukin-6 to the genetically altered mice, the damage mimicked that of the normal mice. "So when we knock out interleukin-6, we can block the effects of angiotensin II," Dr. Caldwell said.

The scientists want to see whether the interleukin-6 antibody can be used to prevent damage by giving it shortly after the onset of diabetes in rodents and as a treatment by using it later in the disease process.

The research was funded by the National Institutes of Health, the Department of Veterans Affairs and postdoctoral fellowship awards from the Juvenile Diabetes Research Foundation International and the American Heart Association.


Story Source:

The above story is based on materials provided by Medical College of Georgia. Note: Materials may be edited for content and length.


Cite This Page:

Medical College of Georgia. "Discovery points toward anti-inflammation treatment for blinding disease." ScienceDaily. ScienceDaily, 18 January 2010. <www.sciencedaily.com/releases/2010/01/100114143312.htm>.
Medical College of Georgia. (2010, January 18). Discovery points toward anti-inflammation treatment for blinding disease. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2010/01/100114143312.htm
Medical College of Georgia. "Discovery points toward anti-inflammation treatment for blinding disease." ScienceDaily. www.sciencedaily.com/releases/2010/01/100114143312.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Stone Fruit Listeria Scare Causes Sweeping Recall

Stone Fruit Listeria Scare Causes Sweeping Recall

Newsy (July 22, 2014) The Wawona Packing Company has issued a voluntary recall on the stone fruit it distributes due to a possible Listeria outbreak. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
CDC Head Concerned About a Post-Antibiotic Era

CDC Head Concerned About a Post-Antibiotic Era

AP (July 22, 2014) Sounding alarms about the growing threat of antibiotic resistance, CDC Director Tom Frieden warned Tuesday if the global community does not confront the problem soon, the world will be living in a devastating post-antibiotic era. (July 22) Video provided by AP
Powered by NewsLook.com
Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins