Abstract:
The search for new probiotics has been regarded as an important approach to improving intestinal health in animals. Bacillus has many advantages, such as strong resistance to harmful external factors, wide distribution, and easy colonization of the intestine. Hence, this study aims to screen for a probiotic Bacillus strain that improves animal intestinal health and to elucidate its probiotic mechanism so as to provide probiotic resources for the development of feed-using probiotic formulations. In this research, a strain of Bacillus was isolated from adult pig feces and named B. tequilensis YB-2. In vitro probiotic experiments showed that B. tequilensis YB-2 had strong acid and bile salt resistance, indicating that this strain can customize in the intestine. To further explore the effect of B. tequilensis YB-2 upon animal intestinal health, DSS-induced murine colitis models were established, and the body weight, colonic morphology, inflammatory cytokines level, and intestinal-barrier- and TLR4/NF-κB-pathway-related protein were determined. The results showed that mice receiving drinking water with 3% DSS were found to develop colitis symptoms, including body weight loss and increased disease activity index (DAI); colon length and microvilli shedding were shortened; tight junctions were disrupted; goblet cells decreased; anti-inflammatory cytokines were inhibited; and pro-inflammatory cytokines and the TLR4/NF-κB signaling pathway were activated. Notably, orally received B. tequilensis YB-2 alleviated symptoms of DSS-induced colitis in mice. The above results indicated that B. tequilensis YB-2 was capable of improving colitis in mice by weakening inflammation and intestinal barrier damage, and its mechanism may involve the TLR4/NF-κB pathway. Overall, this research suggests that B. tequilensis YB-2 has the potential to serve as an animal feed additive to prevent intestinal inflammation.
摘要:
寻找新的益生菌被认为是改善动物肠道健康的重要途径。芽孢杆菌具有许多优点,例如对有害外部因素的强烈抵抗力,分布广泛,和肠道容易定植。因此,本研究旨在筛选改善动物肠道健康的益生菌芽孢杆菌菌株,并阐明其益生菌作用机制,为饲料益生菌制剂的开发提供益生菌资源。在这项研究中,从成年猪粪便中分离出一株芽孢杆菌,命名为B.tegilensisYB-2。体外益生菌实验表明,龙舌兰菌YB-2具有较强的耐酸和耐胆盐能力,表明这种菌株可以在肠道中定制。为进一步探讨龙舌兰菌YB-2对动物肠道健康的影响,建立DSS诱导的小鼠结肠炎模型,和体重,结肠形态学,炎性细胞因子水平,并测定肠屏障和TLR4/NF-κB通路相关蛋白。结果显示,接受3%DSS饮用水的小鼠出现结肠炎症状,包括体重减轻和疾病活动指数(DAI)增加;结肠长度和微绒毛脱落缩短;紧密连接被破坏;杯状细胞减少;抗炎细胞因子被抑制;促炎细胞因子和TLR4/NF-κB信号通路被激活。值得注意的是,口服B.temquilensisYB-2减轻了DSS诱导的小鼠结肠炎的症状。以上结果表明,龙舌兰菌YB-2能够通过减弱炎症和肠屏障损伤来改善小鼠结肠炎,其机制可能涉及TLR4/NF-κB通路。总的来说,这项研究表明,B.telquilensisYB-2有潜力作为动物饲料添加剂,以防止肠道炎症。