Exposure to an herbicide, propyzamide, can trigger inflammatory bowel disease, a new study has found. The latter highlights the importance of environmental factors in autoimmune and inflammatory diseases.
- Inflammatory bowel diseases (or IBD) include Crohn’s disease (CD) and ulcerative colitis (UCH).
- Both are characterized by inflammation of the wall of part of the digestive tract, due to a dysregulation of the intestinal immune system.
- IBD is most often diagnosed between the ages of 20 and 30, but it can occur at any age and 15% of cases concern children. More than 200,000 people are affected in France, according to Inserm.
Inflammatory bowel diseases, which cause chronic gastrointestinal inflammation, are increasingly common in industrialized countries, especially in Western Europe and the United States. Researchers at Brigham and Women’s Hospital, Harvard Medical School’s second-largest teaching hospital in Boston, USA, have identified environmental chemicals that promote gastrointestinal inflammation, including using state-of-the-art technology.
The results of their studypublished on October 19 in the journal Nature, identified a weed killer, propyzamide, as one of the chemicals that increases inflammation in the small and large intestines. This herbicide is commonly used on sports fields and fruit and vegetable crops to kill weeds.
Inflammatory diseases: the importance of environmental factors
“Environmental factors are known to be just as important as genetic factors in influencing the onset of autoimmune and inflammatory diseases”says one of the authors, Professor Francisco Quintana, in a communicated. “As we learn more about these environmental factors, we can develop nationwide strategies to limit exposures. Some chemicals do not appear to be toxic when tested under baseline conditions, but we don’t yet know the effect of chronic low-level exposures over decades or early in development.”he continues.
Using human cell cultures, zebrafish, and mouse studies, the researchers showed that propyzamide interferes with the aryl hydrocarbon receptor (AHR), a protein found in DNA. According to the researchers, this receptor, which has a role in the response to environmental toxins, also seems to have a link with immune regulation. The study describes the mechanism by which this interference leads to increased intestinal inflammation.
A useful discovery in the fight against autoimmune diseases
Professor Quintana adds that this discovery could greatly help in the search for treatments for other autoimmune diseases such as multiple sclerosis and type 1 diabetes. “This method can identify new chemical candidates for epidemiological studies, as well as new mechanisms that regulate autoimmune responses. Additionally, this platform can also be used to screen and design therapeutic anti-inflammatory drugs”he says.
Now, his team is investigating the possibility of creating nanoparticles and probiotics capable of targeting the inflammatory pathway they discovered.
