Medical Bulletin 13/ March/ 2025 - Video

The human gut is home to trillions of bacteria that play vital roles in digestion, immunity, and overall health. When this microbial balance is disturbed, it can contribute to the development of chronic diseases like ulcerative colitis (UC), an inflammatory condition of the large intestine. For some patients, current treatments offer limited relief or carry significant risks, including immune suppression. Researchers are now exploring alternative ways to restore gut health, focusing on the microbiome’s ability to heal the intestinal lining.

The research teams led by Kristina Schoonjans and Rizlan Bernier-Latmani at EPFL, have identified Clostridium scindens, a bacterium that converts primary bile acids into 7α-dehydroxylated bile acids, as a key player in gut healing. Their study shows that supplementing the gut with this bacterium could improve recovery from colonic injury, offering a new potential therapy for UC and related disorders.

The researchers found that these effects were dependent on TGR5, a receptor that responds to 7α-dehydroxylated bile acids, which stimulates the proliferation and differentiation of intestinal stem cells.

To further validate their findings, they analyzed patient data to determine whether similar mechanisms were at play in humans. They found that in UC patients, the lower levels of 7α-dehydroxylated bile acids strongly correlated with impaired intestinal cell renewal. This reinforces the link between bile acid metabolism and intestinal healing. “Our findings highlight the potential of microbiome-targeted strategies to modulate bile acid metabolism and promote gut healing,” says Antoine Jalil, the first author of the study.

Ref: Jalil A, Perin A et al. (2025). Bile acid 7α-dehydroxylating bacteria accelerate injury-induced mucosal healing in the colon. EMBO Molecular Medicine 10 March 2025. DOI: 10.1038/s44321-025-00202-w

Researchers have taken a major step towards producing a more affordable and lower-risk polio vaccine using virus-like particles (VLPs). These particles mimic the outer protein shell of poliovirus, but are empty inside. This means there is no risk of infection, but the VLP still causes the immune system to respond.

In a paper published in Nature Communications, the findings show that VLPs produced in both yeast and insect cells can perform equally or better than the current inactivated polio vaccine (IPV), which creates an immune system response by using a killed version of the poliovirus.

Professor Stonehouse, the senior author of the research said: “Any vaccine is only as effective as the number of children that it reaches. The key is to make vaccines universally accessible, as all children have a right to be protected from diseases such as polio, no matter where they live. Ultimately, VLPs would significantly contribute to vaccine equity.

Currently, IPV is relatively expensive to produce because it requires high levels of bio-containment to minimise the risk of leaks of live poliovirus, which could result in outbreaks. VLPs are non-infectious and would not need to be handled under such stringent bio-safety conditions.

Oral polio vaccine (OPV), which contains live but weakened vaccine-virus, is also used in vaccination against polio.

Non-infectious VLPs are easier to produce than current IPVs and the research has shown they are more temperature stable, thanks to genetic alteration of the outer shell. As they are non-infectious, this means they will be less expensive to produce, helping to improve equitable access to vaccination.

Ref: Sherry, L., Bahar, M.W., Porta, C. et al. Recombinant expression systems for production of stabilised virus-like particles as next-generation polio vaccines. Nat Commun 16, 831 (2025). https://doi.org/10.1038/s41467-025-56118-z

A new study published this week in Child Maltreatment found that in comparison to those who had not been abused in childhood, adults who had experienced both childhood physical and sexual abuse had approximately double the odds of physical and mental health conditions, including angina, arthritis, asthma, COPD, heart attack, depression, and disability -- even after considering respondents’ age, race, income, and health behaviors, as well as obesity.

Those who had been sexually abused, but not physically abused, were 55% to 90% more likely to experience these health outcomes compared to their peers who had not experienced any abuse. Adults who were physically abused, but not sexually abused, also had significantly elevated odds of these health outcomes compared to the non-abused, but the associations were more modest

In exploring this association, the study also examined whether the presence of an adult in the home who made the child feel safe and protected was associated with better long-term health outcomes among children who experienced abuse.

The presence of a protective adult was not only important for children who had experienced abuse, but important for children who had not been abused as well. Children without a protective adult in their home, irrespective of childhood abuse status, were 20% to 40% more likely to experience adverse physical health outcomes and twice as likely to suffer from depression in adulthood.

The study’s authors point to the need for future research to unpack these findings in particular.

“It will be important in future research to investigate why some adults in the home are not adequately protective of children, and to discuss potential primary prevention interventions that can help parents provide a more protective environment for children,” said co-author Philip Baiden, an Associate Professor in the School of Social Work at the University of Texas at Arlington

Ref: The Role of Protective Adults in Mitigating Health Outcomes Linked to Childhood Physical and Sexual Abuse., Child Maltreatment (2025). DOI: 10.1177/10775595251322084