Table_1_Effect of aging on acute pancreatitis through gut microbiota.DOCX

BackgroundCompared to younger people, older people have a higher risk and poorer prognosis of acute pancreatitis, but the effect of gut microbiota on acute pancreatitis is still unknown. We aim to investigate the effect of aging gut microbiota on acute pancreatitis and explore the potential mechanism of this phenomenon.
MethodsEighteen fecal samples from healthy adult participants, including nine older and nine younger adults were collected. C57BL/6 mice were treated with antibiotics for fecal microbiota transplantation from older and younger participants. Acute pancreatitis was induced by cerulein and lipopolysaccharide in these mice. The effect of the aged gut microbiota was further tested via antibiotic treatment before or after acute pancreatitis induction.
ResultsThe gut microbiota of older and younger adults differed greatly. Aged gut microbiota exacerbated acute pancreatitis during both the early and recovery stages. At the same time, the mRNA expression of multiple antimicrobial peptides in the pancreas and ileum declined in the older group. Antibiotic treatment before acute pancreatitis could remove the effect of aging gut microbiota, but antibiotic treatment after acute pancreatitis could not.
ConclusionAging can affect acute pancreatitis through gut microbiota which characterizes the deletion of multiple types of non-dominant species. This change in gut microbiota may potentially regulate antimicrobial peptides in the early and recovery stages. The level of antimicrobial peptides has negative correlations with a more severe phenotype.

背景：与青年人群相比，老年人罹患急性胰腺炎（acute pancreatitis）的风险更高、预后更差，但肠道菌群（gut microbiota）对急性胰腺炎的影响尚未明确。本研究旨在探究衰老肠道菌群对急性胰腺炎的作用，并阐明该现象的潜在机制。
方法：本研究收集了18份来自健康成年受试者的粪便样本，其中老年与青年受试者各9名。将来自老年、青年受试者的粪便菌群分别移植给经抗生素预处理的C57BL/6小鼠，通过雨蛙素（cerulein）与脂多糖（lipopolysaccharide）诱导构建小鼠急性胰腺炎模型。此外，本研究还分别在急性胰腺炎诱导前、后施加抗生素处理，以进一步验证衰老肠道菌群的作用效果。
结果：老年与青年成年人的肠道菌群存在显著差异。衰老肠道菌群可在急性胰腺炎的早期与恢复阶段均加重病情；同时，老年组小鼠胰腺与回肠内多种抗菌肽（antimicrobial peptides）的mRNA表达水平显著降低。在急性胰腺炎诱导前施加抗生素处理可消除衰老肠道菌群的致病效应，但诱导后施加则无此效果。
结论：衰老可通过肠道菌群影响急性胰腺炎的发生发展，该菌群变化的特征为多种非优势菌种的缺失。肠道菌群的此类改变可能在疾病早期与恢复阶段调控抗菌肽的表达，而抗菌肽水平与疾病严重程度呈负相关。