Navigation Links
Scientists find key to growth of 'bad' bacteria in inflammatory bowel disease
Date:2/7/2013

(SACRAMENTO, Calif.) Scientists have long puzzled over why "bad" bacteria such as E. coli can thrive in the guts of those with inflammatory bowel disease (IBD), causing serious diarrhea. Now UC Davis researchers have discovered the answerone that may be the first step toward finding new and better treatments for IBD.

The researchers discovered a biological mechanism by which harmful bacteria grow, edge out beneficial bacteria and damage the gut in IBD. This new understanding, published in the Feb. 8 issue of Science, may help researchers develop new treatments for IBD with fewer side effects than current therapies.

IBD begins when "good" bacteria are mistakenly killed by the immune system, while harmful bacteria multiply resulting in inflammation and damage to the intestines, and chronic episodes of abdominal pain, cramping, diarrhea and other changes in bowel habits. It's estimated that IBD, which includes ulcerative colitis and Crohn's disease, affects 1.4 million people in the U.S., according to the Centers for Disease Control and Prevention.

In test-tube and animal studies, the researchers found that potentially harmful bacteria in the intestine called Enterobacteriaceae use nitrate a byproduct formed during the intestinal inflammation in IBD to grow and thrive. Enterobacteriaceae strains include certain E. coli bacteria, which can worsen the intestinal damage of IBD. Eventually, the intestines of those with IBD become overrun by harmful bacteria, and the numbers of normal good bacteria in the gut decrease.

"Much like humans use oxygen, E. coli can use nitrate as a replacement for oxygen to respire, produce energy and grow," said lead author Andreas Baumler, a professor of medical microbiology and immunology at UC Davis.

"In IBD, nitrate produced by inflammation in the gut allows E. coli to take a deep 'breath,' and beat out our beneficial microbes in the competition for nutrients," he said.

The inflammation in the intestines of those with IBD leads to the release of nitric oxide radicals that are powerful in attacking bacteria, Baumler explained. Yet these nitric oxide radicals are also very unstable, and eventually decompose into nitrate, which can be used by bacteria like E. coli to thrive and grow. By contrast, good bacteria in the gut grows through fermentation a much slower process.

Determining the reasons why bacteria like E. coli can edge out good bacteria in the gut is crucial for determining new ways to halt the IBD disease process, according to Baumler. Current treatments for IBD suppress the immune response through antibiotics, corticosteroids or other powerful immune-modifying drugs. But long-term side effects can limit their use and their effectiveness for IBD patients.

The UC Davis team's research indicates that targeting the molecular pathways that generate nitric oxide and nitrate, as well as other molecules that feed harmful gut bacteria, could calm down and normalize the intestinal environment in IBD, Baumler noted. They are already doing research with one candidate drug that could halt the multiple pathways by which harmful bacteria thrive in IBD.

"The idea would be to inhibit all pathways that produce molecules that can be used by bacteria such as E. coli for respiration and growth," Baumler said. "Essentially you could then smother the bacteria."


'/>"/>

Contact: Carole Gan
carole.gan@ucdmc.ucdavis.edu
916-734-9047
University of California - Davis Health System
Source:Eurekalert

Related medicine news :

1. Scientists Explore How Zinc Fights Off Infection
2. Compound developed by scientists protects heart cells during and after attack
3. Scientists discover how chromosomes keep their loose ends loose
4. Meeting: Scientists to explore 60 topical issues related to human health and the environment
5. Scientists debate CDC recommendations during meningitis outbreak
6. Scientists discover protein that allows safe recycling of iron from old red blood cells
7. MU scientists build harness for powerful radiation cancer therapy
8. Monell scientists identify elusive taste stem cells
9. American Association of Radon Scientists and Technologists (AARST) Releases Nation's First Standard for Mitigating Radon (Radioactivity) in Multifamily Buildings
10. Scientists Find Clue to Aging Reversal in Mice
11. Leading researchers warn of brain drain as scientists struggle to find funding
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/18/2017)... ... August 18, 2017 , ... ... asset protection assistance to communities in North-Central West Virginia, is embarking on a ... at-risk boys in the area. , The Chestnut Mountain Ranch (CMR) is a ...
(Date:8/18/2017)... ... 2017 , ... MLM Insurance Group, a Miami area provider ... is working to support the Take Stock In Children Foundation during a regional ... The Take Stock In Children Foundation (TSC) offers guidance and assistance to low ...
(Date:8/18/2017)... ... August 18, 2017 , ... Goss & Associates ... residential and commercial clients in the greater Houston region, is helping locally recognized ... the fight against cancer. , Founded by Tony and Amber Bender after losing ...
(Date:8/18/2017)... ... August 18, 2017 , ... “Emotions are sacred, valid, honored, encouraged. This ... positive education company Generation Mindful. To help change the mindset of parents and educators ... skills, she created the Time-In Toolkit, which launched on Kickstarter 3 weeks ago and ...
(Date:8/18/2017)... ... ... Hawkins, Pastor and Overseer at The House of Yahweh in Abilene, Texas, has released a ... to the mother of the Savior whom the world calls “Mother Mary”. Yisrayl says when ... role of this historical woman. , “The world bows, kisses the feet of, cries ...
Breaking Medicine News(10 mins):
(Date:8/7/2017)... Mich. , Aug. 7, 2017 Diplomat Pharmacy, ... of Joel Saban as president, effective Aug. 7, ... Urick has decided to pursue other interests and will ... "During his tenure, Paul has served us in multiple leadership ... Specialty Pharmacy in Jun. 2015 and has provided decisive, strategic ...
(Date:8/7/2017)... 7, 2017  Endo International plc (NASDAQ: ... resolve virtually all known U.S. mesh product liability claims ... the known remaining U.S. claims at reasonable values. Under ... the fourth quarter of 2017 and continuing through the ... quarter 2017 results, the Company intends to increase its ...
(Date:8/4/2017)...  Agragen, LLC, a Cincinnati ... nutraceutical, and aquacultural feed sectors, announces a significant ... candidates, AGR131.  This drug is designed to trap ... of patients suffering from inflammatory conditions such as ... Biological pharmaceuticals currently ...
Breaking Medicine Technology: