Featured Research

from universities, journals, and other organizations

Anemia Treatment May Improve Or Worsen Disease, Based On Timing

Date:
February 2, 2008
Source:
Children's Hospital Boston
Summary:
A treatment commonly given for anemia, promotes blood-vessel growth in the eye, an effect that could either improve/worsen disease for patients with cancer, diabetic retinopathy, or retinopathy of prematurity. The effects on retinopathy depend on the timing of when the erythropoietin treatment is given.

Erythropoietin has so far been known to doctors as a hormone that boosts red-blood-cell production. Now, a mouse study led by Lois Smith, MD, PhD, an ophthalmologist at Children's Hospital Boston, shows it also keeps blood vessels alive and growing in the eye. The findings not only add a new function to the hormone, but also give doctors a reason to pause before prescribing it to patients with diseases affected by abnormal blood-vessel growth, such as retinopathy and cancer.

Related Articles


The study also found that whether the hormone is a risk or benefit depends on the timing of administration.

Smith and first author of the study* Jing Chen, PhD, worked in mice with retinopathy, an eye disease that begins when healthy blood vessels nourishing the retina die. Numerous vessels then grow in, but they are deformed. Ultimately, the deformed vessels may pull the retina off the back of the eye, causing blindness.

The researchers measured erythropoietin produced in the retina as the disease progressed. Production was 3 to 10 times below normal during early-stage retinopathy, when healthy blood vessels died, and 12 to 33 times above normal during late-stage retinopathy, when deformed blood vessels grew into the retina. The researchers concluded that erythropoietin helps blood vessels survive and grow in the retina, with effects that may be healthy or harmful.

Next, the team examined whether giving erythropoietin could treat retinopathy. They injected erythropoietin into the bloodstream either early, as the mice lost healthy blood vessels, or later, when deformed blood vessels began to invade--then compared them with untreated mice.

Boosting erythropoietin early slowed the disease. The mice lost half as many healthy blood vessels, causing about 30 percent fewer deformed vessels to grow in. Raising erythropoietin levels later, when deformed blood vessels were present, appeared to accelerate the disease--slightly more deformed blood vessels grew in.

If similar effects are found in humans, and its use is properly timed, then giving erythropoietin early could slow loss of healthy blood vessels in retinopathy, says Smith. "Right now, there is very little out there to treat blood vessel loss in patients with retinopathy. However, further studies on the restoration of normal levels of erythropoietin are needed to translate these results to patients."

In other diseases, like cancer, in which doctors need to slow blood vessel growth, the hormone could be blocked, although clinical trials would need to confirm this idea, she adds.

But given at the wrong time, erythropoietin may make blood vessels grow in an unhealthy way, says Smith. For example, because it boosts red blood cells, erythropoietin is often prescribed to premature babies and diabetic adults for anemia. Some of these patients also have retinopathy. Giving the hormone at the wrong time might help anemia, but worsen the eye disease.

"We're not saying, 'don't do it.' We're saying, 'think about it,'" says Smith. "Physicians should look at the state of the eye before giving erythropoietin to patients with retinopathy. They should consider not giving it to patients with full-blown retinopathy, in which abnormal vessels are present, because our work suggests it may accelerate the disease. However, if a patient is early on in the disease, then our work suggests erythropoietin may be beneficial."

Cancer patients, who often take erythropoietin for anemia, face a similar potential risk, says Smith. "Since erythropoietin has the potential to make blood vessels in tumors grow, it could make tumors worse, although a clinical trial is required to know if this is true in humans."

Overall, Smith says her mouse studies are a reason for doctors to think and researchers to investigate, not for patients to panic.

*This research was published in the February issue of the Journal of Clinical Investigation (online January 24).

The research was funded by the V. Kann Rasmussen Foundation, the NIH, Children's Hospital Boston, the Juvenile Diabetes Foundation, and the Research to Prevent Blindness organization.


Story Source:

The above story is based on materials provided by Children's Hospital Boston. Note: Materials may be edited for content and length.


Cite This Page:

Children's Hospital Boston. "Anemia Treatment May Improve Or Worsen Disease, Based On Timing." ScienceDaily. ScienceDaily, 2 February 2008. <www.sciencedaily.com/releases/2008/01/080130111629.htm>.
Children's Hospital Boston. (2008, February 2). Anemia Treatment May Improve Or Worsen Disease, Based On Timing. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2008/01/080130111629.htm
Children's Hospital Boston. "Anemia Treatment May Improve Or Worsen Disease, Based On Timing." ScienceDaily. www.sciencedaily.com/releases/2008/01/080130111629.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) 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