Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sick from your stomach: Bacterial changes may trigger diseases like rheumatoid arthritis

12.06.2012
The billions of bugs in our guts have a newfound role: regulating the immune system and related autoimmune diseases such as rheumatoid arthritis, according to researchers at Mayo Clinic and the University of Illinois at Urbana-Champaign.

Larger-than-normal populations of specific gut bacteria may trigger the development of diseases like rheumatoid arthritis and possibly fuel disease progression in people genetically predisposed to this crippling and confounding condition, say the researchers, who are participating in the Mayo Illinois Alliance for Technology Based Healthcare.

The study is published in the April 2012 issue of PloS ONE.

"A lot of people suspected that gut flora played a role in rheumatoid arthritis, but no one had been able to prove it because they couldn't say which came first — the bacteria or the genes," says senior author Veena Taneja, Ph.D., a Mayo Clinic immunologist. "Using genomic sequencing technologies, we have been able to show the gut microbiome may be used as a biomarker for predisposition."

The roughly 10 trillion cells that make up the human body have neighbors: mostly bacteria that often help, training the immune system and aiding in digestion, for example. The bacteria in the intestines, in addition to a relatively small number of other microorganisms (the gut microbiome), outnumber human cells 10-to-1.

Researchers found that hormones and changes related to aging may further modulate the gut immune system and exacerbate inflammatory conditions in genetically susceptible individuals.

Nearly 1 percent of the world's population has rheumatoid arthritis, a disease in which the immune system attacks tissues, inflaming joints and sometimes leading to deadly complications such as heart disease. Other diseases with suspected gut bacterial ties include type I diabetes and multiple sclerosis.

Researchers with the Mayo Illinois Alliance for Technology Based Healthcare say that identifying new biomarkers in intestinal microbial populations and maintaining a balance in gut bacteria could help physicians stop rheumatoid arthritis before it starts.

"This study is an important advance in our understanding of the immune system disturbances associated with rheumatoid arthritis. While we do not yet know what the causes of this disease are, this study provides important insights into the immune system and its relationship to bacteria of the gut, and how these factors may affect people with genetic susceptibilities to disease," says Eric Matteson, M.D., chairman of rheumatology at Mayo Clinic, who was not a study author.

Dr. Taneja and her team genetically engineered mice with the human gene HLA-DRB1*0401, a strong indicator of predisposition to rheumatoid arthritis. A set of control mice were engineered with a different variant of the DRB1 gene, known to promote resistance to rheumatoid arthritis. Researchers used these mice to compare their immune responses to different bacteria and the effect on rheumatoid arthritis.

"The gut is the largest immune organ in the body," says co-author Bryan White, Ph.D., director of the University of Illinois' Microbiome Program in the Division of Biomedical Sciences and a member of the Institute for Genomic Biology. "Because it's presented with multiple insults daily through the introduction of new bacteria, food sources and foreign antigens, the gut is continually teasing out what's good and bad."

The gut has several ways to do this, including the mucosal barrier that prevents organisms — even commensal or "good" bacteria — from crossing the lumen of the gut into the human body. However, when commensal bacteria breach this barrier, they can trigger autoimmune responses. The body recognizes them as out of place, and in some way this triggers the body to attack itself, he says.

These mice mimic human gender trends in rheumatoid arthritis, in that females were about three times as likely to generate autoimmune responses and contract the disease. Researchers believe these "humanized" mice could shed light on why women and other demographic groups are more vulnerable to autoimmune disorders and help guide development of new future therapies.

"The next step for us is to show if bugs in the gut can be manipulated to change the course of disease," Dr. Taneja says.

The study was funded by the Mayo-Illinois Alliance for Technology Based Healthcare and a grant from the U.S. Department of Defense.

Co-authors include Andres Gomez; Carl Yeoman, Ph.D.; and Margret Berg Miller, Ph.D., all of University of Illinois; David Luckey; Eric Marietta, Ph.D.; and Joseph Murray, M.D., all of Mayo Clinic.

About Mayo Clinic
Mayo Clinic is a nonprofit worldwide leader in medical care, research and education for people from all walks of life. For more information, visit www.mayoclinic.com and www.mayoclinic.org/news.

Sam Smith | EurekAlert!
Further information:
http://www.mayo.edu
http://www.mayoclinic.org/news

More articles from Health and Medicine:

nachricht Inselspital: Fewer CT scans needed after cerebral bleeding
20.03.2019 | Universitätsspital Bern

nachricht Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>