Featured Research

from universities, journals, and other organizations

Receptor Activation Protects Retina From Diabetes Destruction

Date:
September 21, 2008
Source:
Medical College of Georgia
Summary:
Diabetes can make the beautifully stratified retina look like over-fried bacon. A drug known for it pain-relieving power and believed to stimulate memory appears to prevent this retinal damage that leads to vision loss, researchers say.

A drug known for it pain-relieving power and believed to stimulate memory appears to prevent this retinal damage that leads to vision loss, researchers say.
Credit: Image courtesy of Medical College of Georgia

Diabetes can make the beautifully stratified retina look like over-fried bacon.

Related Articles


A drug known for it pain-relieving power and believed to stimulate memory appears to prevent this retinal damage that leads to vision loss, researchers say.

"The effects of this drug on retinal health are phenomenal," says Dr. Sylvia Smith, retinal cell biologist and co-director of the Vision Discovery Institute in the Medical College of Georgia School of Medicine. She's comparing retinal images from a diabetic mouse model treated with (+)- pentazocine to one that wasn't. Even to the untrained eye, the differences are dramatic.

The findings, published in the September issue of Investigative Ophthalmology & Visual Science, suggest such compounds that bind with the sigma receptor in the eye may be good treatments for the top two causes of vision loss: diabetic retinopathy and glaucoma.

Sigma receptors are ubiquitous in the body, but their role and what naturally activates them are unknowns. Recent research suggests sigma receptors help protect cells from stress by ensuring an adequate level of the properly folded proteins they need for normal function. Dr. Smith and others have shown that sigma receptors are located within the endoplasmic reticulum of cells, which controls protein synthesis and regulates calcium levels. When needed, the receptors appear to chaperone these proteins to the cell powerhouse, or mitochondria. Dr. Smith suspects sigma receptors help manage this hotbed of cell stress. In fact, sigma receptor binding with pentazocine increases with cellular stress.

This cell protection role could help explain the resilience of the retina, which receives light and transforms it to a neural impulse that goes to the brain. The retina can tolerate regular insults, such as the light or high blood sugar, and still function for years. In the case of diabetic retinopathy for example, nerve cell damage and death are gradual, eventually spurring new blood vessels in an apparent attempt to get more blood and oxygen to dying cells. Instead, blood vessel proliferation results in further vision loss.

Dr. Smith' lab is collaborating with other MCG investigators to breed mice without a sigma receptor to better understand the receptor's role and whether regular treatment with the drug has a similar dramatic impact on other animal models of retinal disease. "We need to know if we just hit it lucky with the Akita mouse or do we have something that could be of widespread benefit."

Interestingly, pentazocine's binding with sigma receptors didn't impact insulin levels. "It does not solve that problem of diabetes; however our findings do suggest that just because you are hyperglycemic does not mean you will have diabetic retinopathy," Dr. Smith says.

Her lab's studies of sigma receptors' potential to protect against diabetes' blinding cascade are pioneering but sigma receptors have become a hot topic. Scientists are exploring their potential to treat problems from Alzheimer's to brain tumors to depression. As of early September, there were 2,700 papers on sigma receptors in the literature, Dr. Smith says.

The National Eye Institute funded the study.


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. "Receptor Activation Protects Retina From Diabetes Destruction." ScienceDaily. ScienceDaily, 21 September 2008. <www.sciencedaily.com/releases/2008/09/080909111028.htm>.
Medical College of Georgia. (2008, September 21). Receptor Activation Protects Retina From Diabetes Destruction. ScienceDaily. Retrieved January 30, 2015 from www.sciencedaily.com/releases/2008/09/080909111028.htm
Medical College of Georgia. "Receptor Activation Protects Retina From Diabetes Destruction." ScienceDaily. www.sciencedaily.com/releases/2008/09/080909111028.htm (accessed January 30, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Oxfam Calls for Massive Aid for Ebola-Hit West Africa

Oxfam Calls for Massive Aid for Ebola-Hit West Africa

AFP (Jan. 29, 2015) Oxfam International has called for a multi-million dollar post-Ebola "Marshall Plan", with financial support given by wealthy countries, to help Guinea, Sierra Leone and Liberia to recover. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Are We Winning The Fight Against Ebola?

Are We Winning The Fight Against Ebola?

Newsy (Jan. 29, 2015) The World Health Organization announced the fight against Ebola has entered its second phase as the number of cases per week has steadily dropped. Video provided by Newsy
Powered by NewsLook.com
Calif. Health Officials Campaign Against E-Cigarettes

Calif. Health Officials Campaign Against E-Cigarettes

Newsy (Jan. 29, 2015) The California Health Department says e-cigarettes are a public health risk for both smokers and those who inhale e-cig smoke secondhand. Video provided by Newsy
Powered by NewsLook.com
Measles Scare Sends 66 Calif. Students Home

Measles Scare Sends 66 Calif. Students Home

AP (Jan. 29, 2015) Officials say 66 students at a Southern California high school have been told to stay home through the end of next week because they may have been exposed to measles and are not vaccinated. (Jan. 29) 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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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