The researchers found that, in contrast to their sedentary peers, mice allowed to run freely on an exercise wheel for six weeks had fewer symptoms of colitis after exposure to a chemical agent that induces colitis symptoms in mice.
However, mice forced to run at a moderate pace on a treadmill a few times per week for six weeks had more colitis symptoms and higher mortality after exposure to the agent than sedentary mice, the researchers found.
These seemingly contradictory findings add to a growing body of research into the role of exercise and stress in reducing or increasing the severity of a host of inflammatory states, including those associated with Alzheimer’s disease and infection with the influenza virus.
“We are building a strong case to investigate how exercise affects gut immune function in humans and why exercise may beneficially affect disease activity in ulcerative colitis patients, as a few preliminary studies have indicated,” said University of Illinois graduate student Marc Cook, who led the research with U. of I. kinesiology and community health professor Jeffrey Woods. “Our exciting new data give us some potential causes of these benefits that need to be tested in people, which is our ultimate goal.”
The scientists, whose work is reported in the journal Brain, Behavior, and Immunity, also found that voluntary wheel running significantly reduced the expression of some pro-inflammatory genes in the colon in the mouse model of colitis, while forced treadmill running significantly increased expression of many of those same genes. Forced running on a treadmill by itself, but not voluntary wheel running, also increased expression of an antibacterial signaling protein, suggesting that forced exercise disrupted the microbial environment of the gut.
“There is evidence that prolonged, intense exercise can cause gastrointestinal disruption in competitive athletes. However, very little is known about regularly performed moderately intense exercise, especially in those with inflammatory bowel diseases,” Woods said. “From a public health perspective, this would be important information to gather.”
In humans, inflammatory bowel diseases “cause chronic morbidity that significantly reduces physical functioning and quality of life in afflicted patients,” the authors wrote. Although diseases of the gut, including colitis, appear to arise spontaneously, scientists know that environmental influences such as diet, genetic factors, infection and psychological stress play a role.
The microbial populations of the gut are also key contributors to gastrointestinal health, and disruptions can trigger chronic inflammatory responses, “instigating clinical symptoms, including colon ulcers, rectal bleeding, diarrhea, abdominal pain, fatigue, and an overall altered emotional well-being,” the authors wrote. Ulcerative colitis also “significantly increases the risk of developing colorectal cancer later in life.”
A number of factors may help explain the different physiological responses to voluntary and forced exercise in the mice, including altered gut populations of harmful versus beneficial bacteria and changes to the resident populations of specific immune cells in the gut, the researchers said.
Although more studies must be conducted to clarify the interplay of exercise and stress in maintaining or undermining the health of the gut, the research “supports a role for exercise in the adjunct treatment of ulcerative colitis in humans,” the authors wrote.
The American College of Sports Medicine and the National Institutes of Health supported this research.
Editor’s notes: To reach Jeffrey Woods, call 217-244-8815, email firstname.lastname@example.org. To reach Marc Cook, email email@example.com.
The paper, “Forced Treadmill Exercise Training Exacerbates Inflammation and Causes Mortality While Voluntary Wheel Training is Protective in a Mouse Model of Colitis,” is available online.
Diana Yates | University of Illinois
Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland
Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy