Day: March 12, 2021

A Fungus in Certain Foods Slows Intestinal Healing

A study has found that a fungus found in certain foods such as cheese and processed meats can cause intestinal injuries in humans and mice with Crohn’s disease to fester and impeding healing.

These findings, from researchers at Washington University School of Medicine in St. Louis and the Cleveland Clinic, suggest that there is potentially a diet-based way to treat 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 disease is driven by chronic inflammation in the gastrointestinal tract and immunosuppressive medication is the usual treatment. Crohn’s patients endure flare-ups where digestive tracts are dotted with inflamed, open sores that can persist for up to months.

To understand why intestinal ulcers heal so slowly in some people, the researchers studied mice with injured intestines. 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. D. hansenii can be found in all kinds of cheeses, as well as sausages, beer, wine and other fermented foods.

Introducing D. hansenii into mice with injured intestines slowed down the healing process, and eliminating the fungus with amphotericin B sped it up. In humans, the researchers discovered  D. hansenii in seven out of seven of people with Crohn’s disease, and another analysis of Crohn’s patients found D. hansenii present but only in 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.”

Their results suggest that elimination of the fungus could allow wounds to heal normally again, and minimise flare-ups. In mouse studies, amphotericin B eliminated the fungus but it is of limited use in people since it can only be administered intravenously, therefore an oral antifungal is being researched.

“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.”

Source: Medical Xpress

Journal information: U. Jain et al., “Debaryomyces is enriched in Crohn’s disease intestinal tissue and impairs healing in mice,” Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abd0919

Rate of Twin Births At A Global High

Image by atomicqq from Pixabay

The first comprehensive global survey of twinning has reported an enormous increase in the number of twin births around the world, but appears to be plateauing.

One main reason for the increase is that, due to IVF and other fertility services being more readily available, the number of non-identical twin births is increasing. This is due to practices such as hormone stimulation releasing multiple ova, as well as the now discouraged practice of releasing multiple embryos into the womb in IVF. A systematic review also found that with IVF, letting embryos mature before implantation is also linked to increased odds of monozygotic twins. as well as women becoming pregnant later in life – age increases the likelihood of having natural, non-identical twins, peaking at age 35 to 39.

However, instead of continuing to climb, there are signs that twin births have reached a maximum.

“The trends are really quite striking,” said Christiaan Monden, a professor of sociology and demography at Oxford University. “Over the past 40 to 50 years we’ve seen a strong increase in twinning rates in rich, developed countries, and that has led to more twins in both a relative and an absolute sense than we’ve seen ever before.”

The researchers analysed twinning rates from 2010 to 2015 in 165 countries, which covered 99% of the world’s population. In 112 of those countries, they examined further birth records for 1980 to 1985. 

Although Africa is still the leading continent for twin births, other regions are catching up. The researchers found that, since the 1980s, twinning rates have risen from 9 to 12 per 1000 births, with the greatest rise in more developed regions such as  America (71%), Europe (60%) and Asia (32%).

In the UK, twinning rates rose about 62% but are thought to have fallen since the launch of a campaign to reduce multiple births in 2007. 

Raj Mathur, the chair of the British Fertility Society and a consultant gynaecologist at St Mary’s Hospital, said: “It doesn’t surprise us that twinning rates have increased because the availability of assisted reproduction has increased and also because women are slightly older when they have their first children, and both those things will increase the twin rate.[…]

“I think we’ve reached a peak in terms of twinning rates from medical interventions, certainly in the developed world, but the spread of IVF in Africa and South America is still rather limited on a per capita basis, and there are vast numbers of sub-fertile people in Africa particularly who don’t have access to IVF.

Dr Mathur added a note of caution about IVF, as twins have more risks such as lower birth weights and higher still birth and infant mortality rates

“The challenge will be how to spread IVF to them without also giving them higher twin rates. The majority of twin babies are absolutely fine, but there is no doubt that a twin pregnancy carries greater risks for the mother and the baby, so when we can avoid it we should avoid it. The principle we follow is neatly summed up by the phrase ‘one at a time’,” Mathur said.

Source: The Guardian