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Chinese Herbal Retention Enema for the Treatment of Ulcerative Colitis
Published on: May 16, 2025
Paraclostridium bifermentans exacerbates pathosis in a mouse model of ulcerative colitis
Ryo Kutsuna1, Junko Tomida1, Yuji Morita1
1Department of Microbiology, Aichi Gakuin University Graduate School of Pharmaceutical Science, Nagoya, Aichi, Japan.
Abstract:
Although it has been recognized that intestinal bacteria play an important role in the pathology of human ulcerative colitis (UC), specific pathogenic bacteria for UC have not been identified. We investigated the influence of Paraclostridium bifermentans PAGU1678 strain on the pathology of a UC mouse model and found it increased UC pathosis scores such as loose and bloody stools, reduced diversity of fecal flora, disappearance of the crypt structure of distal colon tissue, destruction of intestinal epithelial cells, and atrophy of the colon. Furthermore, we observed an increase in COX-2, TNF-α, IL-6, IL-1, and IL-17 expression and a decrease in Foxp3 and SOCS3 expression, as inflammation-related factors and inflammatory cytokines, a decrease in the concentration of short chain fatty acids (acetic acid, propionic acid, and butyric acid) in feces, and an increase of intestinal mucosal myeloperoxidase activity. These results suggest that P. bifermentans PAGU1678 is a pathology-exacerbating factor in a mouse model of UC. This study is the first to demonstrate exacerbation of the pathological condition in a mouse model of UC by a single bacterial strain.
Insights
The specific bacterium Paraclostridium bifermentans PAGU1678 exacerbates ulcerative colitis (UC) pathology in mice. This study identifies a single bacterial strain that worsens UC symptoms and gut inflammation.
Area of Science:
- Microbiology
- Gastroenterology
- Immunology
Background:
- Intestinal bacteria are implicated in ulcerative colitis (UC) pathogenesis.
- Specific bacterial culprits driving UC pathology remain unidentified.
Purpose of the Study:
- To investigate the pathogenic role of Paraclostridium bifermentans PAGU1678 in a UC mouse model.
- To elucidate the mechanisms by which this bacterium influences UC severity.
Main Methods:
- Administration of P. bifermentans PAGU1678 to a UC mouse model.
- Assessment of clinical signs, fecal flora diversity, and colon histology.
- Measurement of inflammatory markers (COX-2, TNF-α, IL-6, IL-1, IL-17), regulatory factors (Foxp3, SOCS3), short-chain fatty acids, and myeloperoxidase activity.
Main Results:
- P. bifermentans PAGU1678 significantly worsened UC pathosis scores, including diarrhea and rectal bleeding.
- The bacterial strain reduced fecal flora diversity and induced colon tissue damage, epithelial cell destruction, and atrophy.
- Increased expression of pro-inflammatory cytokines and decreased expression of anti-inflammatory factors were observed, alongside altered short-chain fatty acid levels and increased myeloperoxidase activity.
Conclusions:
- P. bifermentans PAGU1678 acts as a pathology-exacerbating factor in a UC mouse model.
- This is the first study to demonstrate exacerbation of UC pathology by a single bacterial strain in a mouse model.
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