The study aimed to identify the effects of modeling procedures on bacterial communities and to investigate whether different modeling procedures lead to consistent patterns of gut microbiome compositions.

Two irritable bowel syndrome (IBS) rat models maternal separation (MS) alone and multiple-early-adversity modeling (MAM) were established and the gut microbiome were analyzed using 16S-rRNA-based high-throughput sequencing methods.

Rats from both models exhibited visceral hypersensitivity and the two model groups exhibited differences in the extent of visceral sensitivity and fecal water content. The microbial community structure of the two models exhibited significant differences compared to the controls, while the two model groups also exhibited significant differences between them. Furthermore, microbial community functional predictions suggested that the two models exhibited different abundances of metabolisms and pathways. Several common and distinct characteristic differences were also observed between the two model groups. Alloprevotella were more abundant in both model groups, while Butyricicoccus, Turicibacter, Ruminococcus, and Clostridium_sensu_stricto along with the family it belongs to were less abundant relative to controls. In addition, the abundance of Clostridium_IV, Corynebacterium, Rothia, Elusimicrobium, Romboutsia, Allobaculum, Parasutterella, and their related taxa were specifically associated with MS group, whereas Butyricimonas and Vampirovibrio along with its related taxa were specifically associated with MAM group. Among those, Butyricimonas, Butyricicoccus and Corynebacterium were found to partially mediate early adversity exposure-induced visceral hypersensitivity.

Our results highlight the importance in evaluating gut microbiota characteristics in IBS research while also systematically considering potential modeling procedural differences. The microbial compositional/functional differences identified in this study were suggestive to further investigation of mechanisms of early adversity induced IBS.

该研究旨在确定建模程序对细菌群落的影响，并研究不同的建模程序是否会导致肠道微生物组组成的一致模式。

建立了两种肠易激综合征 (IBS) 大鼠模型单独母体分离 (MS) 和多重早期逆境模型 (MAM)，并使用基于 16S-rRNA 的高通量测序方法分析肠道微生物组。

两种模型的大鼠都表现出内脏超敏反应，并且两个模型组表现出内脏敏感程度和粪便含水量的差异。两个模型的微生物群落结构与对照组相比表现出显着差异，而两个模型组之间也表现出显着差异。此外，微生物群落功能预测表明这两种模型表现出不同丰度的代谢和途径。在两个模型组之间也观察到几个共同和明显的特征差异。异普氏菌属在两个模型组中都更丰富，而丁酸球菌属,杆菌属,瘤胃球菌属， 和狭义梭菌与对照组相比，它所属的家族数量较少。此外，丰富的梭菌_IV,棒状杆菌属,罗西亚,肠杆菌属,罗布西亚,异菌属,副黄蜂，它们的相关分类群与 MS 组特别相关，而丁酸单胞菌属和吸血弧菌及其相关的分类群与 MAM 组特别相关。在这些，丁酸单胞菌属,丁酸球菌属和棒状杆菌属被发现部分调解早期逆境暴露引起的内脏超敏反应。

我们的结果强调了在 IBS 研究中评估肠道微生物群特征的重要性，同时还系统地考虑了潜在的建模程序差异。本研究中确定的微生物组成/功能差异提示进一步研究早期逆境诱发 IBS 的机制。