Related Experiment Video
Updated: Jul 18, 2025
Non-invasive Assessment of the Efficacy of New Therapeutics for Intestinal Pathologies Using Serial Endoscopic Imaging of Live Mice
Published on: March 10, 2015
Exposure to okadaic acid could disrupt the colonic microenvironment in rats
Yang Liu1, Tian-Qing Yuan2, Jian-Wei Zheng2
1Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, Guangzhou, China; Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Abstract:
Okadaic acid (OA) is one of the most prevalent marine phycotoxin with complex toxicity, which can lead to toxic symptoms such as diarrhea, vomiting, nausea, abdominal pain, and gastrointestinal discomfort. Studies have shown that the main affected tissue of OA is digestive tract. However, its toxic mechanism is not yet fully understood. In this study, we investigated the changes that occurred in the epithelial microenvironment following OA exposure, including the epithelial barrier and gut bacteria. We found that impaired epithelial cell junctions, mucus layer destruction, cytoskeletal remodeling, and increased bacterial invasion occurred in colon of rats after OA exposure. At the same time, the gut bacteria decreased in the abundance of beneficial bacteria and increased in the abundance of pathogenic bacteria, and there was a significant negative correlation between the abundance of pathogenic bacteria represented by Escherichia/Shigella and animal body weight. Metagenomic analysis inferred that Escherichia coli and Shigella spp. in Escherichia/Shigella may be involved in the process of cytoskeletal remodeling and mucosal layer damage caused by OA. Although more evidence is needed, our results suggest that opportunistic pathogens may be involved in the complex toxicity of OA during OA-induced epithelial barrier damage.
Insights
Okadaic acid (OA) damages the gut lining and alters gut bacteria. Opportunistic pathogens may contribute to OA
Area of Science:
- Marine Toxinology
- Gastroenterology
- Microbiology
Background:
- Okadaic acid (OA) is a prevalent marine phycotoxin causing gastrointestinal distress.
- The precise toxic mechanism of OA, particularly its impact on the digestive tract, remains unclear.
Purpose of the Study:
- To investigate the effects of OA exposure on the epithelial microenvironment, focusing on the epithelial barrier and gut microbiota.
- To elucidate the role of gut bacteria in OA-induced toxicity.
Main Methods:
- Exposure of rats to Okadaic Acid (OA).
- Assessment of epithelial barrier integrity, including cell junctions and mucus layer.
- Analysis of gut bacterial composition using metagenomics.
- Correlation analysis between bacterial abundance and animal body weight.
Main Results:
- OA exposure led to impaired epithelial cell junctions, mucus layer destruction, and increased bacterial invasion in rat colons.
- A shift in gut microbiota was observed, with decreased beneficial bacteria and increased pathogenic bacteria (e.g., Escherichia/Shigella).
- A significant negative correlation was found between pathogenic bacteria abundance and animal body weight.
Conclusions:
- Okadaic acid (OA) disrupts the intestinal epithelial barrier and alters gut microbiota composition.
- Opportunistic pathogens, such as Escherichia coli and Shigella, may play a role in OA-induced cytoskeletal remodeling and mucosal damage.
- These findings suggest opportunistic pathogens might contribute to the complex toxicity of OA during epithelial barrier damage.
