(Press-News.org) Eating is a dangerous business. Naturally occurring toxins in food and potentially harmful foodborne microbes can do a number on our intestines, leading to repeated minor injuries. In healthy people, such damage typically heals in a day or two. But in people with Crohn's disease, the wounds fester, causing abdominal pain, bleeding, diarrhea and other unpleasant symptoms.
Researchers at Washington University School of Medicine in St. Louis and the Cleveland Clinic have discovered that a fungus found in foods such as cheese and processed meats can infect sites of intestinal damage in mice and people with Crohn's and prevent healing. Moreover, treating infected mice with antifungal medication eliminates the fungus and allows the wounds to heal.
The findings, published March 12 in the journal Science, suggest that antifungal drugs and dietary changes are potential new approaches to improving intestinal wound healing and reducing symptoms of Crohn's disease.
"We're not suggesting that people stop eating cheese and processed meat; that would be going far beyond what we know right now," said first author Umang Jain, PhD, an instructor in pathology & immunology at the School of Medicine. "What we know is that this foodborne fungus gets into inflamed, injured tissue and causes harm. We're planning to perform a larger study in people to figure out if there's a correlation between diet and the abundance of this fungus in the intestine. If so, it is possible dietary modulation could lower levels of the fungus and thereby reduce symptoms of Crohn's disease."
Crohn's is a subtype of inflammatory bowel disease. As the name suggests, it is driven by chronic inflammation in the digestive tract and primarily treated with immunosuppressive medications. Crohn's patients endure repeated cycles of gastrointestinal symptom flare-up and remission. During a flare, their digestive tracts are dotted with inflamed, open sores that can persist for weeks or even months.
To understand why intestinal ulcers take so long to heal in some people, Jain and senior author Thaddeus Stappenbeck, MD, PhD, formerly at Washington University and now at the Cleveland Clinic, studied mice whose intestines had been injured. By sequencing microbial DNA at the site of injury, they discovered that the fungus Debaryomyces hansenii was abundant in wounds but not in uninjured parts of the intestine.
People acquire the fungus through their food and drink, Jain said. D. hansenii is commonly found in all kinds of cheeses, as well as sausage, beer, wine and other fermented foods.
Further experiments showed that introducing the fungus into mice with injured intestines slowed down the healing process, and that eliminating D. hansenii with the antifungal drug amphotericin B sped it up.
People with Crohn's disease carry the same fungus as the mice. Jain and Stappenbeck examined intestinal biopsies from seven people with Crohn's disease and 10 healthy people. All seven of the patients harbored the fungus in their gut tissue, as compared with only one of the healthy people. In a separate analysis of 10 Crohn's patients involving tissue samples of both inflamed and uninflamed areas of the gut, the researchers found the fungus in samples from all of the patients but only at sites of injury and inflammation.
"If you look at stool samples from healthy people, this fungus is highly abundant," Jain said. "It goes into your body and comes out again. But people with Crohn's disease have a defect in the intestinal barrier that enables the fungus to get into the tissue and survive there. And then it makes itself at home in ulcers and sites of inflammation and prevents those areas from healing."
The findings suggest that eliminating the fungus might restore normal wound healing and shorten flare-ups. While the drug amphotericin B was effective at eliminating the fungus in mouse studies, it is not widely used in people because it can only be given intravenously. The researchers are working with chemists to develop an effective antifungal that can be taken by mouth. They also are studying whether there is a link between diet and the amount of the fungus in people's digestive tracts.
"Crohn's disease is fundamentally an inflammatory disease, so even if we figured out how to improve wound healing, we wouldn't be curing the disease," Jain said. "But in people with Crohn's, impaired wound healing causes a lot of suffering. If we can show that depleting this fungus in people's bodies - either by dietary changes or with antifungal medications - could improve wound healing, then it may affect the quality of life in ways that we've not been able to do with more traditional approaches."
INFORMATION:
Insights into how bacterial proteins work as a network to take control of our cells could help predict infection outcomes and develop new treatments.
Much like a hacker seizes control of a company's software to cause chaos, disease-causing bacteria, such as E. coli and Salmonella, use miniature molecular syringes to inject their own chaos-inducing agents (called effectors) into the cells that keep our guts healthy.
These effectors take control of our cells, overwhelming their defences and blocking key immune responses, allowing the infection to take hold.
Previously, studies have investigated single effectors. Now a team led by scientists at Imperial College London and The Institute of Cancer ...
A team led by Christoph Utschick and Prof. Rudolf Gross, physicists at the Technical University of Munich (TUM), has developed a coil with superconducting wires capable of transmitting power in the range of more than five kilowatts contactless and with only small losses. The wide field of conceivable applications include autonomous industrial robots, medical equipment, vehicles and even aircraft.
Contactless power transmission has already established itself as a key technology when it comes to charging small devices such as mobile telephones and electric toothbrushes. Users would also like to see contactless charging made available for larger electric machines such as industrial robots, medical equipment and electric vehicles.
Such devices could ...
How do you turn "dumb" headphones into smart ones? Rutgers engineers have invented a cheap and easy way by transforming headphones into sensors that can be plugged into smartphones, identify their users, monitor their heart rates and perform other services.
Their invention, called END ...
Irvine, Calif., March 11, 2021 - Catastrophic collapse of materials and structures is the inevitable consequence of a chain reaction of locally confined damage - from solid ceramics that snap after the development of a small crack to metal space trusses that give way after the warping of a single strut.
In a study published this week in Advanced Materials, engineers at the University of California, Irvine and the Georgia Institute of Technology describe the creation of a new class of mechanical metamaterials that delocalize deformations to prevent failure. They did so by turning to tensegrity, a century-old design principle in which isolated ...
LAWRENCE -- Much like coronavirus, circulating HIV-1 viruses mutate into diverse variants that pose challenges for scientists developing vaccines to protect people from HIV/AIDS.
"AIDS vaccine development has been a decades-long challenge partly because our immune systems have difficulty recognizing all the diverse variants of the rapidly mutating HIV virus, which is the cause of AIDS," said Brandon DeKosky, assistant professor of pharmaceutical chemistry and chemical & petroleum engineering at the University of Kansas.
In the past five years, tremendous progress has been ...
Philadelphia, March 12, 2021 - Researchers from Children's Hospital of Philadelphia (CHOP) have determined what happens at a cellular level as the lung alveolus forms and allows newborns to breathe air. Understanding this process gives researchers a better sense of how to develop therapies and potentially regenerate this critical tissue in the event of injury. The findings were published online today by the journal Science.
The lung develops during both embryonic and postnatal stages, during which lung tissue forms and a variety of cell types perform specific roles. During the transition from embryo to newborn is when the alveolar region of the lung ...
Skoltech researchers were able to show that patterns that can cause neural networks to make mistakes in recognizing images are, in effect, akin to Turing patterns found all over the natural world. In the future, this result can be used to design defenses for pattern recognition systems currently vulnerable to attacks. The paper, available as an arXiv preprint, was presented at the 35th AAAI Conference on Artificial Intelligence (AAAI-21).
Deep neural networks, smart and adept at image recognition and classification as they already are, can still be vulnerable ...
An enzyme called MARK2 has been identified as a key stress-response switch in cells in a study by researchers at Johns Hopkins Bloomberg School of Public Health. Overactivation of this type of stress response is a possible cause of injury to brain cells in neurodegenerative diseases such as Alzheimer's, Parkinson's, and Amyotrophic Lateral Sclerosis. The discovery will make MARK2 a focus of investigation for its possible role in these diseases, and may ultimately be a target for neurodegenerative disease treatments.
In addition to its potential relevance to neurodegenerative diseases, the finding is an advance in understanding basic cell biology.
The paper describing ...
RICHLAND, Wash.--As part of a marathon research effort to lower the cost of carbon capture, chemists have now demonstrated a method to seize carbon dioxide (CO2) that reduces costs by 19 percent compared to current commercial technology. The new technology requires 17 percent less energy to accomplish the same task as its commercial counterparts, surpassing barriers that have kept other forms of carbon capture from widespread industrial use. And it can be easily applied in existing capture systems.
In a study published in the March 2021 edition of International Journal of Greenhouse Gas Control, researchers from the U.S. Department of Energy's Pacific Northwest National Laboratory--along with collaborators from ...
MADISON, Wis. -- Mexican wolves in the American Southwest disappeared more quickly during periods of relaxed legal protections, almost certainly succumbing to poaching, according to new research published Wednesday.
Scientists from the University of Wisconsin-Madison found that Mexican wolves were 121% more likely to disappear -- despite high levels of monitoring through radio collars -- when legal rulings permitted easier lethal and non-lethal removal of the protected wolves between 1998 and 2016. The disappearances were not due to legal removal, the researchers say, but instead were likely caused by poachers hiding evidence of their activities.
The findings suggest that consistently strong protections for endangered predators lead ...
