基于16s rRNA测序分析心理应激小鼠肠道菌群结构特征

The study on structural characteristics of intestinal flora of mice with chronic stress based on 16s rRNA sequencing

目的探讨心理应激(慢性束缚应激)对小鼠肠道菌群分步分类及其结构特征的影响。方法将8周龄,SPF级雄性昆明小鼠随机分为2组,即正常组(C,n=8)和慢性束缚应激组(ST,n=8);ST组小鼠每天在自制式束缚器中限制活动2 h,其余时间2组小鼠在相同环境中自由饮水摄食,束缚实验持续14 d,利用16s rRNA高通量测序技术,检测2组小鼠肠道菌群丰度并对比分析ST组小鼠与C组小鼠的菌群组成差异。结果ST组小鼠粪便菌群的有效序列得到282.00±36.69个操作单元(OTUs)聚类,其明显低于C组(353.00±26.67个OTUs,t=3.468,P=0.010);ST组的Chaol指数明显低于C组(357.93±45.89vs415.45±28.88,t=3.409,P=0.011);ST组的Simpson指数明显高于C组(0.19±0.08vs0.06±0.01,t=-4.325,P=0.003),提示ST组菌落丰富性及多样性低于C组。ST组的菌属中的Helicoba cteraceae(螺杆菌科)、Lactobacillaceae(乳杆菌科)、Muribaculaceae以及Moraxellaceae(莫拉菌科)的含量,与C相比明显的上升(P<0.05);同时,ST组小鼠肠道粪便菌群中的Lachnospiraceae(毛螺菌属)、Prevotellaceae(普雷沃氏菌)、Ruminococcaceae(瘤胃球菌科)、Firmicutes(厚壁菌)、Bacteroidetes(拟杆菌)以及Antinobacteria(抗细菌)的含量,与C相比明显的下降(P<0.05)。结论心理应激诱导小鼠肠道菌群的多样性显著降低,菌群分布均发生显著变化。

Aim To explore the effect of stress(chronic restraint stress)on the stepwise classification and structural characteristics of intestinal flora of mice.Methods Eight week old SPF male Kunming mice were randomly divided into two groups:normal group(C,n=8)and chronic restraint stress group(ST,n=8);The ST group mice were restricted in the self-made restraint device for 2 h every day,and the other time the two groups of mice were free to drink and eat in the same environment.The experiment lasted for 14 days.The intestinal flora of the two groups of mice was detected by 16s rRNA high-throughput sequencing technology,and the difference of the flora composition between ST mice and C mice was compared and analyzed.Results The flora diversity of ST group analyzed and detected 282.00±36.69 operational taxonomic units(OTUs),that were decreased as compare to C group(353.00±26.67 OTUs,t=3.468,P=0.010);ST group Chaol index was decreased as compare to C group(357.93±45.89 vs 415.45±28.88,t=3.409,P=0.011);ST group Simpson index was increased as compare to C group(0.19±0.08 vs 0.06±0.01,t=-4.325,P=0.003),indicating that ST groups flora diversity decreased.The contents of Helicobacterceae,Lactobacilliceae,Muribagulaceae and Moraxellaceae in ST group were significantly higher than those in C group(P<0.05);At the same time,the contents of Lachnospiraceae,Prevotella,Ruminococcaceae,Firmicutes,Bacteroides and Antibacteria in intestinal fecal flora of ST group mice decreased significantly compared with C(P<0.05).Conclusion The diversity of intestinal flora in mice induced by psychological stress decreased significantly,and the distribution of intestinal flora changed significantly.