Featured Research

from universities, journals, and other organizations

Natural Regulator Of Inflammation Identified

Date:
December 24, 2008
Source:
Society for Experimental Biology and Medicine
Summary:
Scientists are seeking to define a role of apo(a) in leukocyte recruitment, and have identified novel activity of apo(a) apolipoprotein that may function as a natural and cell specific suppressor of the inflammatory response in vivo. In addition, a mechanism for this novel function of apo(a) was also identified: Its selective regulation of cytokine production and that these effects of apo(a) are independent of its molecular mimicry of Plg.

In a study to be published in the January 09 issue of Experimental Biology and Medicine, Hoover-Plow and co-workers in seeking to define a role of apo(a) in leukocyte recruitment have identified a novel activity of apo(a) apolipoprotein that may function as a natural and cell specific suppressor of the inflammatory response in vivo. In addition, a mechanism for this novel function of apo(a) was also identified: its selective regulation of cytokine production. These effects of apo(a) are independent of its molecular mimicry of Plg.

Lipoprotein(a) (Lp(a)) is similar to low density lipoprotein (LDL), but contains an additional apolipoprotein, apo(a). Numerous clinical studies conducted over the past 40 years have identified Lp(a) as a risk factor independent from LDL for a variety of cardiovascular pathologies. Much of the focus of apo(a) pathogenic activities has centered on its strong resemblance to plasminogen, the zymogen for plasmin, the primary enzyme for blood clot degradation. In addition to its important role in clot lysis, plasmin is required for leukocyte recruitment in inflammation. While several in vitro studies have demonstrated the interference of apo(a) in plasminogen leukocyte recruitment, evidence for this in vivo has been lacking.

In vivo investigation of Lp(a) function has been impeded by the lack of availability of small animal models. Lp(a) is expressed only in humans, nonhuman primates and the European hedgehog. In this study Hoover-Plow's group utilized mice with apo(a) in a plasminogen deficient or replete background to study leukocyte recruitment in three models of inflammation. Hoover-Plow said "In this study apo(a) impeded neutrophil recruitment in two of the models of inflammation, thioglycollate and lipopolysaccharide induced peritonitis. Apo(a) also inhibited neutrophil chemoattractants, and neutrophil recruitment was restored in mice administered neutrophil chemoattractants. The impaired neutrophil recruitment occurred by a mechanism independent of plasminogen.

While the clinical studies point to pathogenic functions of apo(a), a physiological role of Lp(a) has been elusive, but must exist to account for its role in humans and non-human primates, but not most other species. Our results indicate for the first time that apo(a), independent of plasminogen interaction, inhibits neutrophil recruitment in vivo and functions as a cell specific suppressor of the inflammatory response."

Dr. Steven R. Goodman, Editor-in-Chief of Experimental Biology and Medicine, said "Hoover-Plow and colleagues have demonstrated a novel role for apo(a) as a regulator of inflammation. This represents an important contribution to our understanding of the regulation of neutrophil recruitment during the inflammatory response". Experimental Biology and Medicine is a journal dedicated to the publication of multidisciplinary and interdisciplinary research in the biomedical sciences.


Story Source:

The above story is based on materials provided by Society for Experimental Biology and Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Society for Experimental Biology and Medicine. "Natural Regulator Of Inflammation Identified." ScienceDaily. ScienceDaily, 24 December 2008. <www.sciencedaily.com/releases/2008/12/081224215712.htm>.
Society for Experimental Biology and Medicine. (2008, December 24). Natural Regulator Of Inflammation Identified. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2008/12/081224215712.htm
Society for Experimental Biology and Medicine. "Natural Regulator Of Inflammation Identified." ScienceDaily. www.sciencedaily.com/releases/2008/12/081224215712.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cultural Learning In Wild Chimps Observed For The First Time

Cultural Learning In Wild Chimps Observed For The First Time

Newsy (Oct. 1, 2014) — Cultural transmission — the passing of knowledge from one animal to another — has been caught on camera with chimps teaching other chimps. Video provided by Newsy
Powered by NewsLook.com
Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) — A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) — Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
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

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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