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:3/24/2017)... ... ... who like to educate themselves on current issues and who enjoy gaining knowledge on ... to appreciate and love the "Informed" series, hosted by Rob Lowe. A new ... the world. , Running for charity has become a multi-million dollar enterprise ...
(Date:3/24/2017)... ... 24, 2017 , ... Empower Brokerage, located in Southlake, Texas, ... programs. , In February, 2017, Empower Brokerage introduced their new “Performance Partners” program ... to teach how to maximize their sales efforts, as well as how to ...
(Date:3/24/2017)... ... March 24, 2017 , ... “Finding Christ Through Social ... devotional journal chronicling the writer’s path toward true communion with God. “Finding Christ ... #TruthwithGrace” is the creation of published author Lea Michelle Johnson, a follower of ...
(Date:3/24/2017)... ... ... and Harvest A Cultivation of Christian Love” is the creation of published author, David ... wife, Anna Marie. He and his wife are the proud parents of four grown ... “Shadow and Substance.” , “Love, the agape kind, is seen as more than an ...
(Date:3/24/2017)... ... , ... “The Adventures of Joey, The Dog Who Barks at Puddles”: a ... to the fullest, as God intended. “The Adventures of Joey, The Dog Who Barks ... pursuing her passion for writing, especially about truth and human behavior. , Published by ...
Breaking Medicine News(10 mins):
(Date:3/24/2017)... , March 24, 2017 New England ... recipient of an award including funding and in-kind service ... draw technology.  "Making blood draws less ... making their whole hospital experience better.  We,re looking forward ... technology can help improve care for the kids we ...
(Date:3/24/2017)... YORK , March 24, 2017   ... leading organization within medical affairs in the pharmaceutical ... as the chair of a newly formed scientific ... board members to form the first ever medical ... For more information about the ACMA, please ...
(Date:3/24/2017)... Research and Markets has announced the addition ... - 2035" report to their offering. ... The Deep Learning: Drug Discovery and Diagnostics ... the growing market of deep learning solutions within the healthcare domain. ... emerged as a novel solution to generate relevant insights from medical ...
Breaking Medicine Technology: