动物双歧杆菌A12的肠道动态分布规律及其对便秘缓解效果研究

Study on intestinal dynamic distribution of Bifidobacterium animalis A12 and its effect on constipation relief

[目的]检测动物双歧杆菌A12的肠道动态分布规律及其对小鼠便秘的缓解效果。[方法]采用大鼠动物模型,分别一次灌胃和7 d连续灌胃2.5×10^(9) CFU动物双歧杆菌A12活菌细胞,不同时间点收集肠道内容物,利用菌株特异性引物,应用叠氮溴化丙锭与聚合酶链式反应结合方法定量检测动物双歧杆菌A12在肠道各部位的存活数量;进一步采用小鼠便秘模型,评价动物双歧杆菌A12对便秘小鼠的排便及小肠蠕动情况的改善效果。[结果]一次灌服,动物双歧杆菌A12在胃、回肠、结肠和直肠的排空时间分别为6、24、36和48 h。连续7 d灌服,灌服结束7 d后大鼠盲肠和结肠均可检测到动物双歧杆菌A12活菌细胞,14 d后低于检出限;此外,动物双歧杆菌A12活菌细胞可以显著提高便秘小鼠的排便质量、数量、含水率,及其小肠推进率。[结论]动物双歧杆菌A12可通过胃肠道并在肠道内有至少7 d的留存能力,可以显著缓解便秘症状。

[Objective]The study was to investigate the intestinal dynamic distribution of Bifidobacterium animalis A12 and its effect on constipation in mice.[Methods]The rat model was established by gavage with 2.5×10^(9) CFU live Bifidobacterium animalis A12 for one time or 7 consecutive days.The intestinal contents were collected at different time points,and the survival number of A12 strain in various parts of the intestine was detected quantitatively by propidium monoazide(PMA)-PCR with strain specific primers;the defecation and intestinal peristalsis of A12 strain in constipation mice were evaluated.[Results]The emptying time of strain A12 in stomach,ileum,colon and rectum was 6,24,36 and 48 h,respectively.The results showed that the bacteria could be detected in cecum and colon of rats after 7 days of oral administration,which was lower than the detection limit after 14 days;in addition,living A12 strain could significantly improve the defecation quality,quantity,water content and intestinal propulsion rate of constipation mice.[Conclusion]Bifidobacterium animalis A12 can pass through the gastrointestinal tract alive and have a retention capacity of at least 7 days in the intestine,which can significantly relieve constipation symptoms.