Category: Gastrointestinal

Categories : GastrointestinalTags :

Reducing the Rebleeding Risk from Obscure Gastrointestinal Bleeding

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Anatomy of the gut
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In a study published in Gastrointestinal Endoscopy, clinical investigators found that the five-year risk of rebleeding in obscure gastrointestinal bleeding was found to be as high as 41.7%, but capsule endoscopy examinations and subsequent interventions substantially reduced the risk. Factors such as anticoagulant use were also found to be independent predictors of rebleeding risk.

Obscure gastrointestinal bleeding (OGIB) is defined as gastrointestinal bleeding from a source that cannot be identified on upper or lower gastrointestinal endoscopy. OGIB is considered an important indication for capsule endoscopy (CE). CE is particularly useful for the detection of vascular and small ulcerative lesions, conditions frequently associated with OGIB.

Previous studies have shown that patients with severe comorbidities have a higher rate of positive CE findings (observations of mucosal breaks, vascular lesions, tumours, or blood retention) for OGIB. Additionally, for OGIB in which the initial CE fails to identify bleeding lesions, repeated CE can detect lesions at a higher rate. However, there have been no reports with a sufficiently large number of cases on the long-term outcomes of OGIB detected by CE and the risk of rebleeding.

To fill this knowledge gap, investigators followed up on 389 patients who underwent CE as their initial small intestinal examination for OGIB and evaluated the risk of rebleeding over the long term. In addition, the team evaluated the risk of rebleeding in OGIB, in which no source of rebleeding was found in any part of the gastrointestinal tract, including the small intestine.

The overall cumulative rebleeding rate during the five years after CE was 41.7%. In patients with positive CE findings, the cumulative rebleeding rate was 48.0%. The cumulative rebleeding rate in patients who had therapeutic intervention resulting from positive CE findings was 31.8%.

Furthermore, overt OGIB, anticoagulants, positive balloon-assisted enteroscopy after CE, and iron supplements without therapeutic intervention were found to be independent predictors of rebleeding. Among the components of an index assessing the severity of complications, liver cirrhosis was an independent predictor associated with rebleeding in patients with OGIB.

“If capsule endoscopy can be used to properly diagnose and lead to therapeutic intervention, the risk of rebleeding can be reduced,” concluded study leader Dr Otani. “Even if the endoscopy does not detect any lesions, adequate follow-up is necessary. Here at Osaka Metropolitan University, we have been utilising this tool clinically since its early days and have accumulated some of the world’s leading clinical data. This study revealed a high rebleeding rate in OGIB patients and clarified the effects of rebleeding predictors and therapeutic intervention. We have high expectations that this will lead to better medical care in the future.”

Source: Osaka Metropolitan University

Categories : Diet and Nutrition GastrointestinalTags :

Non-nutritive Sweeteners Impact Human Glycaemic Responses

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Photo by Amit Lahav on Unsplash

Since the late 1800s, non-nutritive sweeteners have been used to provide sweetness without sugar. Long been believed to have no effect on the human body, researchers reporting in the journal Cell now challenge this notion by finding that these sugar substitutes are not inert, and, in fact, some can alter human consumers’ microbiomes and thereby their glycaemic responses – albeit in a highly individualised fashion.

Previous research has already found found that non-nutritive sweeteners affected the microbiomes of mice in ways that could impact their glycaemic responses, something which the same researchers now investigated in humans.

To address this important question, the research team carefully screened over 1300 individuals for those who strictly avoid non-nutritive sweeteners in their day-to-day lives, and identified a cohort of 120 individuals. These participants were broken into six groups: two controls and four who ingested well below the FDA daily allowances of either aspartame, saccharin, stevia, or sucralose.

“In subjects consuming the non-nutritive sweeteners, we could identify very distinct changes in the composition and function of gut microbes, and the molecules they secret into peripheral blood. This seemed to suggest that gut microbes in the human body are rather responsive to each of these sweeteners,” said senior author Eran Elinav, an immunologist and microbiome researcher. “When we looked at consumers of non-nutritive sweeteners as groups, we found that two of the non-nutritive sweeteners, saccharin and sucralose, significantly impacted glucose tolerance in healthy adults. Interestingly, changes in the microbes were highly correlated with the alterations noted in people’s glycaemic responses.”

To prove the microbiomes were responsible, the researchers transferred microbial samples from the study subjects to mice that have been raised in completely sterile conditions, with no microbiome of their own.

“The results were quite striking,” explained Elinav. “In all of the non-nutritive sweetener groups, but in none of the controls, when we transferred into these sterile mice the microbiome of the top responder individuals collected at a time point in which they were consuming the respective non-nutritive sweeteners, the recipient mice developed glycaemic alterations that very significantly mirrored those of the donor individuals. In contrast, the bottom responders’ microbiomes were mostly unable to elicit such glycaemic responses,” he added. “These results suggest that the microbiome changes in response to human consumption of non-nutritive sweetener may, at times, induce glycaemic changes in consumers in a highly personalised manner.”

Elinav says that he expects the effects of the sweeteners will vary across individuals because of how unique our microbiomes are. “We need to raise awareness of the fact that non-nutritive sweeteners are not inert to the human body as we originally believed. With that said, the clinical health implications of the changes they may elicit in humans remain unknown and merit future long-term studies.”

“In the meantime, we need to continue searching for solutions to our sweet tooth craving, while avoiding sugar, which is clearly most harmful to our metabolic health,” says Elinav. “In my personal view, drinking only water seems to be the best solution.”

Source: Science Daily

Categories : GastrointestinalTags :

Body Posture, Stomach Motility Affect Oral Pill Bioavailability

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While oral administration of a pill or capsule is a simple and cheap route, it is also the most complex way for the human body to absorb an active pharmaceutical ingredient, due to the stomach environment’s influence on bioavailability. Using highly detailed computer simulations, researchers have now found that stomach motility and posture (leaning right, left or backwards) significantly affect bioavailability.

The rate of dissolution and gastric emptying of the dissolved active pharmaceutical ingredient (API) into the duodenum is modulated by gastric motility, physical properties of the pill, and the contents of the stomach. This results in varying rates of pill dissolution and nonuniform emptying of the drug into the duodenum and, occasionally, gastric dumping in the case of modified-release dosage. Current in vitro procedures for assessing dissolution of oral drugs do not simulate this process well.

In Physics of Fluids, researchers used a biomimetic computer simulation based on the realistic anatomy and morphology of the stomach (a ‘StomachSim’) to investigate and quantify the effect of body posture and stomach motility on drug bioavailability over the first few minutes of absoprtion.

 The simulations show that changes in posture can potentially have a significant (up to 83%) effect on the emptying rate of the API into the duodenum. A 45 degree lean to the left greatly reduced the amount of active ingredient per cycle released into the duodenum, while a lean to the right dramatically increased it over the upright case.

Similarly, the researchers found that a reduction in antral contractility associated with gastroparesis significantly reduced the dissolution of the pill as well as emptying of the API into the duodenum. The simulations show that for an equivalent motility index, the reduction in gastric emptying due to neuropathic gastroparesis is larger by a factor of about five compared to myopathic gastroparesis.

“Oral administration is surprisingly complex despite being the most common choice for drug administration,” said co-author Rajat Mittal. “When the pill reaches the stomach, the motion of the stomach walls and the flow of contents inside determine the rate at which it dissolves. The properties of the pill and the stomach contents also play a major role.

“However, current experimental or clinical procedures for assessing the dissolution of oral drugs are limited in their ability to study this, which makes it a challenge to understand how the dissolution is affected in different stomach disorders, such as gastroparesis, which slows down the emptying of the stomach.”

Together, these issues pose several challenges for the design of drug delivery.

“In this work, we demonstrate a novel computer simulation platform that offers the potential for overcoming these limitations,” said Mittal. “Our models can generate biorelevant data on drug dissolution that can provide useful and unique insights into the complex physiological processes behind the oral administration of pills.”

The researchers note that the simulation required a lot of computational time, only capturing the first few minutes of the process, and are working on faster methods to capture differences over the period of an hour.

Source: American Institute of Physics

Categories : GastrointestinalTags :

Gold Nanoparticles Ease IBD Inflammatory Symptoms

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Gold bars
Photo by Jingming Pan on Unsplash

In a Chinese study published in Fundamental Research, researchers explored a treatment for inflammatory bowel disease (IBD) using ultrasmall gold nanoparticles. Previous studies showed that these nanoclusters effectively eliminate a variety of reactive oxygen species (ROS), elevated levels of which are commonly found in the gastrointestinal tract of IBD patients.

IBD includes ulcerative colitis and Crohn’s disease, both of which tend to be debilitating, lifelong conditions that can prove fatal in severe cases. Currently, there is no cure for IBD. The main clinical treatments are drugs such as aminosalicylic acid preparations and corticosteroids, but they are often accompanied by gastrointestinal problems, anaemia, and various intestinal complications. Finding alternative, more effective options is a priority for researchers.

The team found that administering gold (Au25) nanoclusters orally to mice suffering from colitis eliminated ROS, increased antioxidant enzymes, and inhibited pro-inflammatory cytokines, without any obvious side effects. According to paper author Fei Wang of China’s The Seventh Affiliated Hospital of Sun Yat-Sen University, a reduction in the inflammation in the gastrointestinal tracts of the mice was observed within 24 hours. She added: “And the fact that these nanoclusters can be administered orally, means there is no need for invasive procedures.”

Additionally, the team found that the nanoclusters have a number of benefits when compared with natural enzymes used in traditional IBD treatments, including lower cost, better stability, mass synthesis and easier storage. Wang explained: “The storage of Au25 nanoclusters was not affected by pH, temperature or solution medium, and their good physiological stability and acid resistance meant they were easily able to access the inflamed colon. They also have good biocompatibility and chemical stability and can remove a variety of ROS.”

Wang concluded: “Au25 nanoclusters offer a promising strategy in the research field of nanomedicine therapy for IBD. We believe this study demonstrates their value as a scientific basis and experimental basis for the clinical treatment of IBD.”

Source: EurekAlert!

Categories : GastrointestinalTags :

Ulcerative Colitis Treatment Fixes Inflammation in Gut Microbiota

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Gut microbiome. Credit: Darryl Leja, NIH

Researchers have developed a new oral treatment for ulcerative colitis that takes the innovative approach of focusing on reducing inflammation in gut microbiota.

Published in Pharmaceutics, the study comprised a two-step approach to fighting ulcerative colitis. First, the researchers reduced inflammation in gut microbiota from a mouse using an anti-inflammatory drug candidate delivered by lipid nanoparticles. Then, they orally administered the end products of these treated microbiota to the same mouse, resulting in a new, effective way to prevent ulcerative colitis.

Studies have shown that irregular gut microbiota composition is linked to ulcerative colitis, and altering this composition can effectively treat a variety of chronic diseases, including ulcerative colitis. However, current methods such as faecal microbiota transplants carry a serious infection risk because they involve the transmission of drug-resistant organisms.

In this study, the researchers developed an organism-free strategy in which gut microbiota were altered in test tubes, and then microbiota-secreted metabolites were transferred back to the host. Analysis of faeces from mice with ulcerative colitis, researchers found that a natural lipid nanoparticle-encapsulated drug candidate modified the composition of inflamed gut microbiota, which were cultured outside of the host, and the secreted metabolites.

The researchers found that their M13/nLNP nano formulation shifted the inflamed microbiota composition toward being non-inflamed. This altered microbiota composition induced significant changes in secreted metabolites, and when these metabolites were fed to mice, they established strong protection against the formation of chronic inflammation.

“Our study demonstrates that modifying microbiota outside of the host using M13/nLNP effectively reshaped the microbial secreted metabolites,” commented Dr Didier Merlin, a professor at Georgia State University. “Oral transfer of these metabolites might be an effective and safe therapeutic approach for preventing chronic ulcerative colitis.”

“Our strategy to tackle the progression of ulcerative colitis might offer an alternative and complementary approach for better managing this disease,” said Dr Chunhua Yang, a research assistant professor at the Institute for Biomedical Sciences at Georgia State. “Although this study demonstrates the anti-inflammatory effects of metabolites modified outside of the organism, further investigations are required to characterise the specific bacteria that contribute to the anti-inflammatory metabolites and to identify anti-inflammatory metabolite structures.”

Source: Georgia State University

Categories : Gastrointestinal Mental HealthTags :

IBD and Depression is a Two-way Street

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Photo by Andrea Piacquadio on Pexels

While irritable bowel disease (IBD) and depression are known to occur together, scientists report a clinical overlap of these conditions in the Journal of Gastroenterology and Hepatology, implying the existence of a two-way relationship. Patients diagnosed with IBD were nine times as likely to develop depression than the general population. Their siblings who did not suffer from IBD were almost two times as likely to develop depression.

Conversely, patients with depression were two times as likely to develop IBD, and their siblings without depression were more than one and a half times as likely to develop IBD.

“This research reveals a clinical overlap between both conditions, and is the first study to investigate the two-way association between IBD and depression in siblings,” said Bing Zhang, MD, a gastroenterologist with Keck Medicine and co-lead author of the study.

The researchers drew on the data of more than 20 million people from Taiwan’s National Health Insurance Research Database. For 11 years, they tracked patients with either IBD or depression and their siblings without either condition, comparing onset of depression or IBD with a control group of people without either condition, but with similar age, sex and socioeconomic status.

Zhang hypothesises that many factors may contribute to the bidirectional nature of the disorders, including environmental stressors, the gut microbiome and genetics.

“The finding that people with IBD are more prone to depression makes sense because IBD causes constant gastrointestinal symptoms that can be very disruptive to a patient’s life,” he said. “And the elevated depression risk among siblings of IBD patients may reflect caregiver fatigue if the siblings have a role in caring for the patient.”

What surprised researchers was that patients with depression were prone to IBD. Zhang speculates that this discovery may have to do with what is known as the gut-brain axis, a scientifically established connection between the gastrointestinal system and the central nervous system, which consists of the spinal cord and the brain.

For example, he said, inflammation of the brain, which plays a role in depression, may be linked to the inflammation of the gastrointestinal tract, a hallmark of IBD.

The researchers are not sure why siblings of patients with depression are more likely to be diagnosed with IBD. Zhang surmises that there may be a shared genetic susceptibility for either disease that presents differently in family members.

Zhang hopes that the study findings will encourage health care professionals to take both family history and the relationship between gastrointestinal and mood disorders into consideration when evaluating or treating patients with either IBD or depression.

Through more research and better understanding of the gut-brain axis, he envisions leveraging the newfound connection between the conditions to improve the prevention, diagnosis and treatment of IBD and mental disorders.

Source: University of Southern California – Health Sciences

Categories : GastrointestinalTags :

Growing up with Dogs (But not Cats) Protects Against Crohn’s Disease

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Young children who grow up with a dog or in a large family appears to confer some protection later on in life from Crohn’s disease, according to a study presented at Digestive Disease Week® (DDW) 2022.

Crohn’s disease is a common type of inflammatory bowel disease that often develops in young adults, smokers, and those with a close family member who has IBD. Symptoms include diarrhoea, abdominal pain and weight loss. Treatments currently aim to prevent symptom flare-ups through diet modification, medication, and surgery.

“Our study seems to add to others that have explored the ‘hygiene hypothesis’ which suggests that the lack of exposure to microbes early in life may lead to lack of immune regulation toward environmental microbes,” said Williams Turpin, PhD, the study’s senior author and a research associate with Mount Sinai Hospital and the University of Toronto.

Researchers used an environmental questionnaire to collect information from nearly 4300 first-degree relatives of people with Crohn’s disease enrolled in the Crohn’s and Colitis Canada Genetic, Environmental, and Microbial (CCC-GEM) project. Using responses to the questionnaire and historical data collected at the time of recruitment, Dr Turpin and his team analysed several environmental factors, including family size, the presence of dogs or cats as household pets, the number of bathrooms in the house, living on a farm, drinking unpasteurised milk and drinking well water. The analysis also included age at the time of exposure.

The study found that exposure to dogs, especially from ages 5 to 15, was associated with healthy gut permeability and balance between the microbes in the gut and the body’s immune response, which may all help protect against Crohn’s disease. Similar effects were observed with exposure to dogs across all age groups.

“We did not see the same results with cats, though we are still trying to determine why,” Dr Turpin said. “It could potentially be because dog owners get outside more often with their pets or live in areas with more green space, which has been shown previously to protect against Crohn’s.”

Another protective factor seemed to be living with three or more family members in the first year of life, which was associated with microbiome composition later in life. The gut microbiome is believed to play a role in a number of health conditions, such as inflammatory bowel disease, colorectal cancer, diabetes, and high blood pressure.

Dr Turpin and his colleagues hope their findings may assist physicians in asking detailed questions of patients to determine who is at highest risk. However, he noted that the early life environmental factors were assessed by questionnaires, so caution is warranted in interpreting these results due to possible recall bias at recruitment. The reasons dog ownership and larger families appear to provide protection from Crohn’s remain unclear.

Source: Digestive Disease Week

Categories : GastrointestinalTags :

Using Ablation Therapy to Treat Stomach Disorders

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Researchers have shown that ablation therapy, often used to correct an abnormally beating heart, could be used to correct disorders of the stomach such as ‘stomach dysrhythmias’. They outline the results of their work in AJP Gastrointestinal and Liver Physiology.

In normal circumstances the stomach is coordinated by underlying bioelectrical ‘slow wave’ activity, which coordinates the contraction of the muscles that mix and move contents into and through the gastrointestinal (GI) tract.  When these electrical slow waves don’t work as they should, described as ‘stomach dysrhythmias’, it can lead to severe GI disorders and symptoms of nausea, vomiting, pain and bloating, and is often untreatable.

When dysrhythmic activity occurs in the heart it results in atrial fibrillation, which is often treated with ablation therapy in which tissues are precisely ‘burnt’ to control the naturally occurring electricity in the heart. Dr Tim Angeli-Gordon and PhD student Zahra Aghababaie of the ABI have shown that the technique could also be applied to control the naturally occurring bioelectrical “slow wave” activity in the stomach.

With last year’s publication of the team’s initial research using ablation in the stomach, they demonstrated that it was possible to use the technique to block the electrical activation of the stomach in localised regions. “The more recent paper builds on that foundational work and is an important advance because we have now shown that we can eliminate abnormal electrical activation with ablation, and also that the normal electrical activation of the stomach can be restored after ablation,” said Dr Angeli-Gordon. “Although these studies were done in our pre-clinical lab, they demonstrate the powerful potential of ablation in the stomach which may now be able to be translated as a therapy for patients suffering from gastrointestinal disorders.”

Source: EurekAlert!

Categories : Gastrointestinal Mental Health PaediatricsTags :

GI Issues and Anxiety Linked in Children with Autism

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Male doctor with young girl patient
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A new study has found a bi-directional relationship between gastrointestinal (GI) issues and internalised symptoms such as anxiety in children and adolescents with autism, which means the symptoms seem to be affecting each other. The findings could inform future precision medicine research aimed at developing personalised treatments for people with autism experiencing gastrointestinal issues. The study appears in the Journal of Autism and Developmental Disorders.

Autism is known to be often associated with GI issues, and is often overlooked in children despite being a source of pain and anxiety. Food preferences are often for carbohydrates and processed foods. The most common cause of GI issues in children with autism are abdominal pain, constipation, chronic diarrhea and gastroesophageal reflux disease (GERD).

“Research has shown gastrointestinal issues are associated with an increased stress response as well as aggression and irritability in some children with autism,” said Brad Ferguson, an assistant research professor. “This likely happens because some kids with autism are unable to verbally communicate their gastrointestinal discomfort as well as how they feel in general, which can be extremely frustrating. The goal of our research is to find out what factors are associated with gastrointestinal problems in individuals with autism so we can design treatments to help these individuals feel better.”

In the study, Ferguson and his team analysed health data from more than 620 under-18 patients with autism who experience gastrointestinal issues. Then, the researchers examined the relationship between the GI issues and internalised symptoms. Ferguson explained the findings provide more evidence on the importance of the ‘gut–brain axis’ in GI disorders in individuals with autism.

“Stress signals from the brain can alter the release of neurotransmitters like serotonin and norepinephrine in the gut which control gastrointestinal motility, or the movement of stool through the intestines. Stress also impacts the balance of bacteria living in the gut, called the microbiota, which can alter gastrointestinal functioning,” Ferguson said. “The gut then sends signals back to the brain, and that can, in turn, lead to feelings of anxiety, depression and social withdrawal. The cycle then repeats, so novel treatments addressing signals from both the brain and the gut may provide the most benefit for some kids with gastrointestinal disorders and autism.”

Ferguson is collaborating with David Beversdorf, a neurologist who also studies gastrointestinal problems in individuals with autism. Beversdorf had recently helped identify specific RNA biomarkers linked with gastrointestinal issues in children with autism.

“Interestingly, the study from Beversdorf and colleagues found relationships between microRNA that are related to anxiety behaviour following prolonged stress as well as depression and gastrointestinal disturbance, providing some converging evidence with our behavioural findings,” Ferguson said.

Ferguson and Beversdorf are now together investigating the effects of a stress-reducing medication on GI issues in a clinical trial. Ferguson cautioned that treatment could be effective for certain people with autism but not others.

“Our team uses a biomarker-based approach to find what markers in the body are common in those who respond favourably to certain treatments,” Ferguson said. “Our goal is to eventually develop a quick test that tells us which treatment is likely to work for which subgroups of patients based on their unique biomarker signature, including markers of stress, composition of gut bacteria, genetics, co-occurring psychological disorders, or a combination thereof. This way, we can provide the right treatments to the right patients at the right time.”

Source: University of Missouri-Columbia

Categories : GastrointestinalTags :

Damaging Candida Strains in Inflammatory Bowel Disease

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Anatomy of the gut
Source: Pixabay CC0

In the human gut, individual strains of Candida albicans are incredibly varied, and some C. albicans strains may damage the gut of patients with inflammatory bowel disease (IBD), according to a new study published in Nature. The findings suggest a possible way to tailor treatments to individual patients in the future.

The researchers used an array of techniques to study Candida strains from the colons of people with or without ulcerative colitis, a chronic, relapsing and remitting inflammatory disorder of the colon and rectum and one of the main forms of IBD. They found that certain strains, which they call “high-damaging,” produce candidalysin, a potent toxin that damages immune cells.

“Such strains retained their “high-damaging” properties when they were removed from the patient’s gut and triggered pro-inflammatory immunity when colonised in mice, replicating certain disease hallmarks,” said senior author Dr Iliyan Iliev, an associate professor of immunology in medicine at Weill Cornell Medicine.

IBD is estimated to affect between one in 11 and one in 26 people worldwide. The condition can significantly impact patients’ quality of life. There are a handful of available therapies, but treatments may not always be effective. The study showed that steroids, one of the common treatments, may not work. Treating mice with steroids to suppress intestinal inflammation failed in the presence of “high-damaging” C. albicans strains.

“Our findings suggest that C. albicans strains do not cause spontaneous intestinal inflammation in a host with intact immunity,” Dr Iliev said. “But they do expand in the intestines when inflammation is present and can be a factor that influences response to therapy in our models and perhaps in patients.”

Most studies of the human microbiome in healthy individuals and those with IBD have focused on bacteria and viruses, but recent studies  by Dr Iliev and others has highlighted the role of fungi. Intestinal fungi play an important role in regulating immunity at surfaces exposed to the outside, such as the intestines and lungs, due to their potent immune-stimulating characteristics. While the mycobiota – the body’s fungi community – has been linked to IBD, the pro-inflammatory of gut the mycobiota was not understood.

In the new study, the investigators initially found that Candida strains, while highly diverse in the intestines of both patients with and without colitis, were on average more abundant in the patients with IBD. But that did not explain disease outcomes in individual patients. So, the investigators set out to identify the characteristics of these strains that cause damage and how they relate to individual patients.

The researchers observed that in the patients with ulcerative colitis, severe disease was associated with the presence of “high-damaging” Candida strains, all of which produce the candidalysin toxin. The scientists showed that the toxin damages immune cells called macrophages, prompting a storm of the pro-inflammatory cytokine IL-1β.

The researchers then grew macrophages in the presence of Candida strains and found that the ability of the strains to induce IL-1β corresponded closely to the severity of colitis in the patients.

“Our finding shows that a cell-damaging toxin candidalysin released by “high damaging” C. albicans strains during the yeast-hyphae morphogenesis triggers pathogenic immunological responses in the gut,” said first author Dr Xin Li.

Experiments in mice delineated that candidalysin-producing “high-damaging” strains induced the expansion of a population of T cells called Th17 cells and other inflammation-associated immune cells, such as neutrophils.

“Neutrophils contribute to tissue damage and their accumulation is a hallmark of active IBD,” said Dr Ellen Scherl, a professor of inflammatory bowel disease. “The indication that these processes might in part be driven by a fungal toxin released by yeast strains in specific patients could potentially inform personalized treatment approaches.”

Consistent with this finding, blocking IL-1β signalling had a dramatic effect in reducing colitis signs in mice that harboured these highly pro-inflammatory strains. The researchers noted that other recent studies have linked IBD to IL-1β in a general way, prompting ongoing investigations of drugs targeting related pathways as potential IBD therapies.

“We do not know whether specific strains are acquired by specific patients during the course of disease or whether they have been always there and become a problem during episodes of active disease” Dr Iliev said. “Nevertheless, our findings highlight a mechanism by which commensal fungal strains can turn against their host and overdrive inflammation.”

The team’s next steps are to investigate the persistence candidalysin-producing strains in the inflamed colon of specific IBD patients, as well as ways to choose patients for mycobiome therapy.

Source: Weill Cornell Medicine