Article Type
Changed
Tue, 08/08/2023 - 12:12

A popular ingredient in the American diet has been linked to ulcerative colitis. The ingredient is soybean oil, which is very common in processed foods. In fact, U.S. per capita consumption of soybean oil increased more than 1,000-fold during the 20th century.

In a study from the University of California, Riverside, and UC Davis, published in Gut Microbes, mice fed a diet high in soybean oil were more at risk of developing colitis. 

The likely culprit? Linoleic acid, an omega-6 fatty acid that composes up to 60% of soybean oil.

Small amounts of linoleic acid help maintain the body’s water balance. But Americans derive as much as 10% of their daily energy from linoleic acid, when they need only 1%-2%, the researchers say.

The findings build on earlier research linking a high-linoleic acid diet with inflammatory bowel disease, or IBD, in humans. (Previous research in mice has also linked high consumption of the oil with obesity and diabetes in the rodents.)

For the new study, the researchers wanted to drill down into how linoleic acid affects the gut.
 

How linoleic acid may promote inflammation

In mice, the soybean oil diet upset the ratio of omega-3 to omega-6 fatty acids in the gut. This led to a decrease in endocannabinoids, lipid-based molecules that help block inflammation.

Enzymes that metabolize fatty acids are “shared between two pathways,” said study coauthor Frances Sladek, PhD, professor of cell biology at UC Riverside. “If you swamp the system with linoleic acid, you’ll have less enzymes available to metabolize omega-3s into good endocannabinoids.”

The endocannabinoid system has been linked to “visceral pain” in the gut,  said Punyanganie de Silva, MD, MPH, an assistant professor at Brigham & Women’s Hospital, Boston, who was not involved in the study. But the relationship between the endocannabinoid system and inflammation has yet to be fully explored.

“This is one of the first papers that has looked at the association between linoleic acid and the endocannabinoid system,” Dr. de Silva said. “[The researchers] propose a potential new mechanism of how linoleic acid may increase inflammation” – that is, through its impact on the endocannabinoid system. 
 

Changes in the gut microbiome

The gut microbiome of the mice also showed increased amounts of adherent invasive E. coli, a type of bacteria that grows by using linoleic acid as a carbon source. A “very close relative” of this bacteria has been linked to IBD in humans, Dr. Sladek said.

Using a method known as metabolomics, the researchers studied 3,000 metabolites in the intestinal cells of both the mice and the bacteria. Endocannabinoids decreased in both.

“We were actually quite surprised. I didn’t realize that bacteria made endocannabinoids,” Dr. Sladek said.

Helpful bacteria, such as the probiotic lactobacillus species, died off. The mice also had increased levels of oxylipins, which are correlated with obesity in mice and colitis in humans.
 

A high–linoleic acid diet could mean a leaky gut

Linoleic acid binds to a protein known as HNF-4 alpha. Disrupting the expression of this protein can weaken the intestinal barrier, letting toxins flow into the body – more commonly known as leaky gut. Mice on the soybean oil diet had decreased levels of the protein and more porous intestinal barriers, raising the risk for inflammation and colitis. “The HNF-4 alpha protein is conserved from mouse to human, so whatever’s happening to it in the context of the mouse gut, there’s a very high chance that a similar effect could be seen in humans as well,” said study coauthor Poonamjot Deol, PhD, an assistant professional researcher at UC Riverside.

Still, Dr. de Silva urges “some caution when interpreting these results,” given that “this is still experimental and needs to be reproduced in clinical studies as humans have a far more varied microbiome and more variable environmental exposures than these very controlled mouse model studies.”

Dr. de Silva says cooking with olive oil can “help increase omega-3 to omega-6 ratios” and advises eating a varied diet that includes omega-3 fats, such as flaxseed and walnuts, and minimal amounts of processed foods and saturated fats.

Looking ahead, endocannabinoids are being explored as “a potential therapy for treating IBD symptoms,” said Dr. Deol. She hopes to delve further into how linoleic acid affects the endocannabinoid system.

A version of this article first appeared on WebMD.com.

Publications
Topics
Sections

A popular ingredient in the American diet has been linked to ulcerative colitis. The ingredient is soybean oil, which is very common in processed foods. In fact, U.S. per capita consumption of soybean oil increased more than 1,000-fold during the 20th century.

In a study from the University of California, Riverside, and UC Davis, published in Gut Microbes, mice fed a diet high in soybean oil were more at risk of developing colitis. 

The likely culprit? Linoleic acid, an omega-6 fatty acid that composes up to 60% of soybean oil.

Small amounts of linoleic acid help maintain the body’s water balance. But Americans derive as much as 10% of their daily energy from linoleic acid, when they need only 1%-2%, the researchers say.

The findings build on earlier research linking a high-linoleic acid diet with inflammatory bowel disease, or IBD, in humans. (Previous research in mice has also linked high consumption of the oil with obesity and diabetes in the rodents.)

For the new study, the researchers wanted to drill down into how linoleic acid affects the gut.
 

How linoleic acid may promote inflammation

In mice, the soybean oil diet upset the ratio of omega-3 to omega-6 fatty acids in the gut. This led to a decrease in endocannabinoids, lipid-based molecules that help block inflammation.

Enzymes that metabolize fatty acids are “shared between two pathways,” said study coauthor Frances Sladek, PhD, professor of cell biology at UC Riverside. “If you swamp the system with linoleic acid, you’ll have less enzymes available to metabolize omega-3s into good endocannabinoids.”

The endocannabinoid system has been linked to “visceral pain” in the gut,  said Punyanganie de Silva, MD, MPH, an assistant professor at Brigham & Women’s Hospital, Boston, who was not involved in the study. But the relationship between the endocannabinoid system and inflammation has yet to be fully explored.

“This is one of the first papers that has looked at the association between linoleic acid and the endocannabinoid system,” Dr. de Silva said. “[The researchers] propose a potential new mechanism of how linoleic acid may increase inflammation” – that is, through its impact on the endocannabinoid system. 
 

Changes in the gut microbiome

The gut microbiome of the mice also showed increased amounts of adherent invasive E. coli, a type of bacteria that grows by using linoleic acid as a carbon source. A “very close relative” of this bacteria has been linked to IBD in humans, Dr. Sladek said.

Using a method known as metabolomics, the researchers studied 3,000 metabolites in the intestinal cells of both the mice and the bacteria. Endocannabinoids decreased in both.

“We were actually quite surprised. I didn’t realize that bacteria made endocannabinoids,” Dr. Sladek said.

Helpful bacteria, such as the probiotic lactobacillus species, died off. The mice also had increased levels of oxylipins, which are correlated with obesity in mice and colitis in humans.
 

A high–linoleic acid diet could mean a leaky gut

Linoleic acid binds to a protein known as HNF-4 alpha. Disrupting the expression of this protein can weaken the intestinal barrier, letting toxins flow into the body – more commonly known as leaky gut. Mice on the soybean oil diet had decreased levels of the protein and more porous intestinal barriers, raising the risk for inflammation and colitis. “The HNF-4 alpha protein is conserved from mouse to human, so whatever’s happening to it in the context of the mouse gut, there’s a very high chance that a similar effect could be seen in humans as well,” said study coauthor Poonamjot Deol, PhD, an assistant professional researcher at UC Riverside.

Still, Dr. de Silva urges “some caution when interpreting these results,” given that “this is still experimental and needs to be reproduced in clinical studies as humans have a far more varied microbiome and more variable environmental exposures than these very controlled mouse model studies.”

Dr. de Silva says cooking with olive oil can “help increase omega-3 to omega-6 ratios” and advises eating a varied diet that includes omega-3 fats, such as flaxseed and walnuts, and minimal amounts of processed foods and saturated fats.

Looking ahead, endocannabinoids are being explored as “a potential therapy for treating IBD symptoms,” said Dr. Deol. She hopes to delve further into how linoleic acid affects the endocannabinoid system.

A version of this article first appeared on WebMD.com.

A popular ingredient in the American diet has been linked to ulcerative colitis. The ingredient is soybean oil, which is very common in processed foods. In fact, U.S. per capita consumption of soybean oil increased more than 1,000-fold during the 20th century.

In a study from the University of California, Riverside, and UC Davis, published in Gut Microbes, mice fed a diet high in soybean oil were more at risk of developing colitis. 

The likely culprit? Linoleic acid, an omega-6 fatty acid that composes up to 60% of soybean oil.

Small amounts of linoleic acid help maintain the body’s water balance. But Americans derive as much as 10% of their daily energy from linoleic acid, when they need only 1%-2%, the researchers say.

The findings build on earlier research linking a high-linoleic acid diet with inflammatory bowel disease, or IBD, in humans. (Previous research in mice has also linked high consumption of the oil with obesity and diabetes in the rodents.)

For the new study, the researchers wanted to drill down into how linoleic acid affects the gut.
 

How linoleic acid may promote inflammation

In mice, the soybean oil diet upset the ratio of omega-3 to omega-6 fatty acids in the gut. This led to a decrease in endocannabinoids, lipid-based molecules that help block inflammation.

Enzymes that metabolize fatty acids are “shared between two pathways,” said study coauthor Frances Sladek, PhD, professor of cell biology at UC Riverside. “If you swamp the system with linoleic acid, you’ll have less enzymes available to metabolize omega-3s into good endocannabinoids.”

The endocannabinoid system has been linked to “visceral pain” in the gut,  said Punyanganie de Silva, MD, MPH, an assistant professor at Brigham & Women’s Hospital, Boston, who was not involved in the study. But the relationship between the endocannabinoid system and inflammation has yet to be fully explored.

“This is one of the first papers that has looked at the association between linoleic acid and the endocannabinoid system,” Dr. de Silva said. “[The researchers] propose a potential new mechanism of how linoleic acid may increase inflammation” – that is, through its impact on the endocannabinoid system. 
 

Changes in the gut microbiome

The gut microbiome of the mice also showed increased amounts of adherent invasive E. coli, a type of bacteria that grows by using linoleic acid as a carbon source. A “very close relative” of this bacteria has been linked to IBD in humans, Dr. Sladek said.

Using a method known as metabolomics, the researchers studied 3,000 metabolites in the intestinal cells of both the mice and the bacteria. Endocannabinoids decreased in both.

“We were actually quite surprised. I didn’t realize that bacteria made endocannabinoids,” Dr. Sladek said.

Helpful bacteria, such as the probiotic lactobacillus species, died off. The mice also had increased levels of oxylipins, which are correlated with obesity in mice and colitis in humans.
 

A high–linoleic acid diet could mean a leaky gut

Linoleic acid binds to a protein known as HNF-4 alpha. Disrupting the expression of this protein can weaken the intestinal barrier, letting toxins flow into the body – more commonly known as leaky gut. Mice on the soybean oil diet had decreased levels of the protein and more porous intestinal barriers, raising the risk for inflammation and colitis. “The HNF-4 alpha protein is conserved from mouse to human, so whatever’s happening to it in the context of the mouse gut, there’s a very high chance that a similar effect could be seen in humans as well,” said study coauthor Poonamjot Deol, PhD, an assistant professional researcher at UC Riverside.

Still, Dr. de Silva urges “some caution when interpreting these results,” given that “this is still experimental and needs to be reproduced in clinical studies as humans have a far more varied microbiome and more variable environmental exposures than these very controlled mouse model studies.”

Dr. de Silva says cooking with olive oil can “help increase omega-3 to omega-6 ratios” and advises eating a varied diet that includes omega-3 fats, such as flaxseed and walnuts, and minimal amounts of processed foods and saturated fats.

Looking ahead, endocannabinoids are being explored as “a potential therapy for treating IBD symptoms,” said Dr. Deol. She hopes to delve further into how linoleic acid affects the endocannabinoid system.

A version of this article first appeared on WebMD.com.

Publications
Publications
Topics
Article Type
Sections
Teambase XML
<?xml version="1.0" encoding="UTF-8"?>
<!--$RCSfile: InCopy_agile.xsl,v $ $Revision: 1.35 $-->
<!--$RCSfile: drupal.xsl,v $ $Revision: 1.7 $-->
<root generator="drupal.xsl" gversion="1.7"> <header> <fileName>164554</fileName> <TBEID>0C04B803.SIG</TBEID> <TBUniqueIdentifier>MD_0C04B803</TBUniqueIdentifier> <newsOrJournal>News</newsOrJournal> <publisherName>Frontline Medical Communications</publisherName> <storyname/> <articleType>2</articleType> <TBLocation>QC Done-All Pubs</TBLocation> <QCDate>20230803T112844</QCDate> <firstPublished>20230803T113414</firstPublished> <LastPublished>20230803T115048</LastPublished> <pubStatus qcode="stat:"/> <embargoDate/> <killDate/> <CMSDate>20230803T113414</CMSDate> <articleSource>FROM GUT MICROBES</articleSource> <facebookInfo/> <meetingNumber/> <byline>Sarah Amandolare</byline> <bylineText>SARAH AMANDOLARE </bylineText> <bylineFull>SARAH AMANDOLARE </bylineFull> <bylineTitleText/> <USOrGlobal/> <wireDocType/> <newsDocType>News</newsDocType> <journalDocType/> <linkLabel/> <pageRange/> <citation/> <quizID/> <indexIssueDate/> <itemClass qcode="ninat:text"/> <provider qcode="provider:imng"> <name>IMNG Medical Media</name> <rightsInfo> <copyrightHolder> <name>Frontline Medical News</name> </copyrightHolder> <copyrightNotice>Copyright (c) 2015 Frontline Medical News, a Frontline Medical Communications Inc. company. All rights reserved. This material may not be published, broadcast, copied, or otherwise reproduced or distributed without the prior written permission of Frontline Medical Communications Inc.</copyrightNotice> </rightsInfo> </provider> <abstract/> <metaDescription>“[The researchers] propose a potential new mechanism of how linoleic acid may increase inflammation” – that is, through its impact on the endocannabinoid system</metaDescription> <articlePDF/> <teaserImage/> <teaser>The likely culprit? Linoleic acid, an omega-6 fatty acid that composes up to 60% of soybean oil.</teaser> <title>How soybean oil could lead to gut inflammation</title> <deck/> <disclaimer/> <AuthorList/> <articleURL/> <doi/> <pubMedID/> <publishXMLStatus/> <publishXMLVersion>2</publishXMLVersion> <useEISSN>0</useEISSN> <urgency/> <pubPubdateYear/> <pubPubdateMonth/> <pubPubdateDay/> <pubVolume/> <pubNumber/> <wireChannels/> <primaryCMSID/> <CMSIDs/> <keywords/> <seeAlsos/> <publications_g> <publicationData> <publicationCode>im</publicationCode> <pubIssueName/> <pubArticleType/> <pubTopics/> <pubCategories/> <pubSections/> </publicationData> <publicationData> <publicationCode>fp</publicationCode> <pubIssueName/> <pubArticleType/> <pubTopics/> <pubCategories/> <pubSections/> </publicationData> </publications_g> <publications> <term canonical="true">21</term> <term>15</term> </publications> <sections> <term>39313</term> <term canonical="true">27970</term> </sections> <topics> <term canonical="true">213</term> </topics> <links/> </header> <itemSet> <newsItem> <itemMeta> <itemRole>Main</itemRole> <itemClass>text</itemClass> <title>How soybean oil could lead to gut inflammation</title> <deck/> </itemMeta> <itemContent> <p>A popular ingredient in the American diet has been linked to ulcerative colitis. The ingredient is soybean oil, which is very common in processed foods. In fact, U.S. per capita consumption of soybean oil increased more than <a href="https://pubmed.ncbi.nlm.nih.gov/21367944/">1,000-fold</a> during the 20th century.</p> <p>In a <a href="https://www.tandfonline.com/doi/full/10.1080/19490976.2023.2229945">study</a> from the University of California, Riverside, and UC Davis, published in Gut Microbes, mice fed a diet high in soybean oil were more at risk of developing colitis. <br/><br/>The likely culprit? Linoleic acid, an omega-6 fatty acid that composes up to 60% of soybean oil. <br/><br/>Small amounts of linoleic acid help maintain the body’s water balance. But Americans derive as much as 10% of their daily energy from linoleic acid, when they need only 1%-2%, the researchers say. <br/><br/>The findings build on <a href="https://pubmed.ncbi.nlm.nih.gov/19628674/">earlier</a> <a href="https://www.nature.com/articles/nrgastro.2009.224">research</a> linking a high-linoleic acid diet with inflammatory bowel disease, or IBD, in humans. (Previous <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132672">research</a> in mice has also linked high consumption of the oil with obesity and diabetes in the rodents.) <br/><br/>For the new study, the researchers wanted to drill down into how linoleic acid affects the gut. <br/><br/></p> <h2>How linoleic acid may promote inflammation</h2> <p>In mice, the soybean oil diet upset the ratio of omega-3 to omega-6 fatty acids in the gut. This led to a decrease in endocannabinoids, lipid-based <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8067588/">molecules</a> that help block<a href="https://pubmed.ncbi.nlm.nih.gov/22269477/"> inflammation.</a></p> <p>Enzymes that metabolize fatty acids are “shared between two pathways,” said study coauthor Frances Sladek, PhD, professor of cell biology at UC Riverside. “If you swamp the system with linoleic acid, you’ll have less enzymes available to metabolize omega-3s into good endocannabinoids.” <br/><br/>The endocannabinoid system has been linked to “visceral pain” in the gut,  said Punyanganie de Silva, MD, MPH, an assistant professor at Brigham &amp; Women’s Hospital, Boston, who was not involved in the study. But the relationship between the endocannabinoid system and inflammation has yet to be fully explored. <br/><br/>“This is one of the first papers that has looked at the association between linoleic acid and the endocannabinoid system,” Dr. de Silva said. <span class="tag metaDescription">“[The researchers] propose a potential new mechanism of how linoleic acid may increase inflammation” – that is, through its impact on the endocannabinoid system.</span> <br/><br/></p> <h2>Changes in the gut microbiome </h2> <p>The gut microbiome of the mice also showed increased amounts of adherent invasive <em>E. coli</em>, a type of bacteria that grows by using linoleic acid as a carbon source. A “very close relative” of this bacteria has been <a href="https://pubmed.ncbi.nlm.nih.gov/15300573/">linked to IBD</a> in humans, Dr. Sladek said. </p> <p>Using a method known as <a href="https://www.ebi.ac.uk/training/online/courses/metabolomics-introduction/what-is/">metabolomics</a>, the researchers studied 3,000 metabolites in the intestinal cells of both the mice and the bacteria. Endocannabinoids decreased in both. <br/><br/>“We were actually quite surprised. I didn’t realize that bacteria made endocannabinoids,” Dr. Sladek said. <br/><br/>Helpful bacteria, such as the probiotic lactobacillus species, died off. The mice also had increased levels of oxylipins, which are correlated with <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5624939/">obesity in mice</a> and colitis in humans.<br/><br/></p> <h2>A high–linoleic acid diet could mean a leaky gut</h2> <p>Linoleic acid binds to a protein known as HNF-4 alpha. <a href="https://pubmed.ncbi.nlm.nih.gov/27166517/">Disrupting the expression of this protein</a> can weaken the intestinal barrier, letting toxins flow into the body – more commonly known as leaky gut. Mice on the soybean oil diet had decreased levels of the protein and more porous intestinal barriers, raising the risk for inflammation and colitis. “The HNF-4 alpha protein is conserved from mouse to human, so whatever’s happening to it in the context of the mouse gut, there’s a very high chance that a similar effect could be seen in humans as well,” said study coauthor Poonamjot Deol, PhD, an assistant professional researcher at UC Riverside. </p> <p>Still, Dr. de Silva urges “some caution when interpreting these results,” given that “this is still experimental and needs to be reproduced in clinical studies as humans have a far more varied microbiome and more variable environmental exposures than these very controlled mouse model studies.” <br/><br/>Dr. de Silva says cooking with olive oil can “help increase omega-3 to omega-6 ratios” and advises eating a varied diet that includes omega-3 fats, such as flaxseed and walnuts, and minimal amounts of processed foods and saturated fats. <br/><br/>Looking ahead, endocannabinoids are being explored as “a potential therapy for treating IBD symptoms,” said Dr. Deol. She hopes to delve further into how linoleic acid affects the endocannabinoid system. </p> <p> <em>A version of this article first appeared on <span class="Hyperlink"><a href="https://www.webmd.com/digestive-disorders/news/20230802/how-soybean-oil-could-lead-gut-inflammation">WebMD.com</a></span>.</em> </p> </itemContent> </newsItem> <newsItem> <itemMeta> <itemRole>teaser</itemRole> <itemClass>text</itemClass> <title/> <deck/> </itemMeta> <itemContent> </itemContent> </newsItem> </itemSet></root>
Article Source

FROM GUT MICROBES

Disallow All Ads
Content Gating
No Gating (article Unlocked/Free)
Alternative CME
Disqus Comments
Default
Use ProPublica
Hide sidebar & use full width
render the right sidebar.
Conference Recap Checkbox
Not Conference Recap
Clinical Edge
Display the Slideshow in this Article
Medscape Article
Display survey writer
Reuters content
Disable Inline Native ads
WebMD Article