Featured Research

from universities, journals, and other organizations

Sudden Removal Of Fat Impairs Immune Function In Rodents, Biologists Find

Date:
March 31, 2003
Source:
Indiana University
Summary:
A liposuction-like procedure called lipectomy results in a loss of humoral immune protection in two commonly studied rodent models, the prairie vole and the Siberian hamster, scientists have found.

BLOOMINGTON, Ind. -- A liposuction-like procedure called lipectomy results in a loss of humoral immune protection in two commonly studied rodent models, the prairie vole and the Siberian hamster, scientists have found.

The report by a team of researchers at Indiana University, Ohio State University and Johns Hopkins University was made available online this week by The Royal Society. Their study is the first to show that even a moderate loss of fat leads to decreased amounts of infection-fighting IgG antibodies.

"We were able to show that even a subtle decrease in fat can decrease humoral immunity, which has the potential to increase disease susceptibility," said Indiana University biologist Gregory Demas, who led the study. "We knew that immune function is energetically costly, but it is now clear that animals use energy stored as fat to bolster immunity and likely to combat infection."

The researchers also found that immune system function improved after the regrowth of fat tissue that had been removed.

The research team divided 54 adult male prairie voles and 36 adult male Siberian hamsters into three experimental groups. The individuals from one of these groups had epididymal white adipose tissue removed, the second group had inguinal white adipose tissue removed, and the third group had a surgical procedure but had no adipose tissue removed.

Half of the rodents in each of the three groups were then exposed to an immune system-roiling antigen called keyhole limpet hemocyanin (KLH) four weeks after surgery. The other half of each group received KLH 12 weeks after surgery. KLH is known to induce a strong immune response in voles and hamsters without making the animals sick.

After a few days, the researchers measured each rodent's bloodstream concentrations of IgG antibodies raised in response to the presence of KLH. Lower concentrations of the antibodies signify impaired immune function. The researchers found that immune function in KLH-inoculated voles appeared normal four weeks after surgery but was impaired 12 weeks after surgery. KLH-inoculated hamsters, however, showed impaired immune function four weeks after surgery but seemed to have recovered normal immune function 12 weeks after surgery, when they had regained normal levels of body fat. Demas attributed the different responses to the two species' unique physiologies.

Demas said the study strengthens biologists' perception that immune systems require a lot of energy to perform "optimally" in any mammal.

"It's not yet known whether there is also a strong connection in humans between energy stored as fat and immune function, but it's clearly important to see whether it holds true in humans as well," he said.

All animals used in the study were treated in accordance with the standards of the Johns Hopkins University Institutional Animal Care and Use Committee. Deborah Drazen of Johns Hopkins University and Randy Nelson of Ohio State University also contributed to the report, which will appear in the May 7 issue of Proceedings B of the Royal Society. Sue Carter of the University of Illinois at Chicago provided the prairie vole line, and Katherine Wynne-Edwards of Queens University (Canada) provided the Siberian hamster line. The study was funded by a National Research Service Award grant from the National Institutes of Health.


Story Source:

The above story is based on materials provided by Indiana University. Note: Materials may be edited for content and length.


Cite This Page:

Indiana University. "Sudden Removal Of Fat Impairs Immune Function In Rodents, Biologists Find." ScienceDaily. ScienceDaily, 31 March 2003. <www.sciencedaily.com/releases/2003/03/030331043840.htm>.
Indiana University. (2003, March 31). Sudden Removal Of Fat Impairs Immune Function In Rodents, Biologists Find. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2003/03/030331043840.htm
Indiana University. "Sudden Removal Of Fat Impairs Immune Function In Rodents, Biologists Find." ScienceDaily. www.sciencedaily.com/releases/2003/03/030331043840.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) 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