Featured Research

from universities, journals, and other organizations

Source of protection against saturated fat found

Date:
November 30, 2010
Source:
Cell Press
Summary:
Scientists have identified a protein without which diets high in saturated fat lead to a massive inflammatory response that can prove fatal. The studies in mice suggest that deficiencies in this protective pathway could promote inflammation in those who regularly consume high levels of saturated fat.

A new report in the December Cell Metabolism identifies a protein without which diets high in saturated fat lead to a massive inflammatory response that can prove fatal. The studies in mice suggest that deficiencies in this protective pathway could promote inflammation in those who regularly consume high levels of saturated fat.

Related Articles


"In mice without this protein that ate a lot of saturated fat, the lymph nodes blew up to extreme levels," said Sander Kersten of the Nutrigenomics Consortium and Wageningen University in the Netherlands. "I'd never seen anything like it before."

Kersten said that a connection between saturated fat, inflammation, and chronic diseases, including cardiovascular disease and diabetes, has long been recognized. But it really hadn't been clear why saturated fats can cause harm.

Normally, dietary fats are broken down into fatty acids. Those fatty acids are incorporated in small particles called chylomicrons and released into the circulation after passing through the lymphatic system of the intestine. Those circulating fats are later broken down by an enzyme (called lipoprotein lipase or LPL) to feed tissues such as the heart and skeletal muscle that depend on fatty acids for fuel. But LPL is also found at high levels in immune cells called macrophages, whose job it is to gobble up invaders or foreign particles.

Earlier studies had shown that LPL activity depends on a protein called Angiopoietin-like protein 4 (Angptl4). In the new study, the researchers wanted to find out what happens in mice lacking Angptl4 when they are fed a diet high in fat.

Mice deficient for the protein showed a severe immune reaction and ultimately died. Those abnormalities occurred only when the animals were fed saturated fats, not unsaturated or medium-chain fats, the researchers report. Lymph nodes associated with the intestine expanded dramatically as the macrophages within them filled up with lipids.

"Normally, this should not be the case," Kersten said, as those immune cells are designed to protect the body against bacteria or other foreign invaders.

When macrophages were incubated in the lab with a milky fluid containing lymph and fatty acids, Angptl4 showed reduced formation of lipid-laden foam cells, lower expression of inflammatory genes, and of a form of cellular stress.

The data show that Angptl4 is a key player in the protection against the severe proinflammatory effects of dietary saturated fat, the researchers conclude.

The findings may have implications for the approximately three percent of the human population who carry a mutation in the Angptl4 gene. "Based on our data in mice, it can be hypothesized that human subjects homozygous for the E40K mutation in Angptl4, which has reduced ability to inhibit LPL and is associated with lower plasma triglycerides, may be particularly sensitive to the proinflammatory effects of dietary saturated fat," the researchers wrote.

Kersten also speculates that Western diets loaded in saturated fats could perhaps overwhelm the system, particularly if it is "not working perfectly." The findings point more generally to an underappreciated role for the intestinal lymphatic system in managing the response to high concentrations of dietary fats.


Story Source:

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


Journal Reference:

  1. Laeticia Lichtenstein, Frits Mattijssen, Nicole J. de Wit, Anastasia Georgiadi, Guido J. Hooiveld, Roelof van der Meer, Yin He, Ling Qi, Anja Kφster, Jouke T. Tamsma et al. Angptl4 Protects against Severe Proinflammatory Effects of Saturated Fat by Inhibiting Fatty Acid Uptake into Mesenteric Lymph Node Macrophages. Cell Metabolism, Volume 12, Issue 6, 580-592, 1 December 2010 DOI: 10.1016/j.cmet.2010.11.002

Cite This Page:

Cell Press. "Source of protection against saturated fat found." ScienceDaily. ScienceDaily, 30 November 2010. <www.sciencedaily.com/releases/2010/11/101130122029.htm>.
Cell Press. (2010, November 30). Source of protection against saturated fat found. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2010/11/101130122029.htm
Cell Press. "Source of protection against saturated fat found." ScienceDaily. www.sciencedaily.com/releases/2010/11/101130122029.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) — Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com
Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) — Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Despite Rising Death Toll, Many Survive Ebola

Despite Rising Death Toll, Many Survive Ebola

AP (Oct. 23, 2014) — The family of a Dallas nurse infected with Ebola in the US says doctors can no longer detect the virus in her. Despite the mounting death toll in West Africa, there are survivors there too. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) — Is your child ready? Video provided by Working Mother
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