{
  "abstract": "Background Severe Acute Pancreatitis (SAP) is a critical illness often accompanied by a severe systemic inflammatory response and distal organ injury. Recent studies suggest that gut microbiota dysbiosis plays a key role in the development and progression of SAP, potentially exacerbating inflammation and systemic complications via the ‘gut-pancreas axis.’ Melatonin, an endogenous hormone with potent anti-inflammatory and antioxidant properties, has been shown to protect against various forms of digestive system injury. However, its specific regulatory effects on the gut microbial ecosystem in SAP and the underlying mechanisms remain unclear. Therefore, this study aims to investigate whether melatonin can alleviate the pathological process of SAP by reshaping the gut microbiota.Methods The mouse model of severe acute pancreatitis was established in this study. The animals were divided into a healthy control group, a disease group, and a melatonin-treated group. Fecal samples were collected from each group. Gut microbiota structure was analyzed by 16S rRNA gene sequencing. The Shannon index was used to assess alpha diversity, while NMDS analysis was employed for beta diversity comparison. Further examination of microbiota composition changes was conducted.Results Alpha diversity analysis revealed that the Shannon index of the gut microbiota in the disease group was significantly lower than that in the healthy control group (p < 0.05). The melatonin-treated group showed a slight increase in alpha diversity compared to the disease group. NMDS analysis indicated a significant separation in microbial composition between the healthy control group and the disease group (stress = 0.077, R = 0.73254, P = 0.001). In terms of microbiota composition, the disease group exhibited significantly higher levels of Escherichia-Shigella and a reduced abundance of Bacteroidaceae. Melatonin intervention partially restored these microbial imbalances.Conclusions Severe acute pancreatitis leads to decreased gut microbiota diversity and disrupted composition in mice. Melatonin treatment can partially restore microbial diversity and modulate microbiota composition. These findings suggest that the remodeling of the gut microbiota by melatonin may be one of the mechanisms through which it alleviates SAP.",
  "authors": [
    {
      "affiliations": [
        "Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China"
      ],
      "name": "Penghui Wang"
    },
    {
      "affiliations": [
        "Department of Microbiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China"
      ],
      "name": "Hong Cao"
    }
  ],
  "title": "IDDF2026-ABS-0038 Melatonin remodels the gut microbiota in mice with severe acute pancreatitis",
  "uid": "0ce4abc9-b362-56ff-bd32-7ce005c9d653"
}