血根碱对断奶仔猪肠道黏膜屏障功能的作用机制研究

Weaning stress results in piglet diarrhea, immunosuppression, intestinal mucosal morphology changes, increased intestinal permeability and intestinal mucosal barrier injury and dysfunction and so on. Zinc Oxide (Zn O) is often excessively used in piglet industry as a mitigation measure although some problems like food safety and environmental pollution exist. As a kind of environmental protection feed additive, plant extracts are much more used widely than before in the production of piglets. Sanguinarine has the effect of improving intestinal health, promoting growth, reducing intestinal inflammation and immune regulation. However, the effect of hemagglutinine on the intestinal mucosal barrier function of weaned piglets and its mechanism were less. This project by in vivo and in vitro experiments on the LPS stress, changes of mucosal immune function, weaned piglets intestinal mucosa morphology and intestinal epithelial tight junctions and permeability, and to investigate the regulation of weaned piglets intestinal mucosal barrier protection function and the possible mechanism of the serum and intestinal cytokine balance and TLR4/NF- B signaling pathway and other ways to reveal the maintenance of intestinal mucosal barrier integrity and anti-inflammatory mechanism. The results of this study will provide a solution and theoretical basis for searching and exploring new ways to maintain intestinal health, reduce the mortality rate of weaned piglets, replace and reduce the use of antibiotics in feed.

断奶应激造成的肠道黏膜屏障受损是导致断奶仔猪肠道健康问题的主要原因，生产中常以添加抗生素和氧化锌作为缓解措施，而随之带来的食品安全及生态环境问题已引起世界范围内的高度关注，目前植物提取物作为极具潜力的替代方案已受到越来越的重视，其中血根碱因具有改善肠道健康、促进生长、降低肠道炎症及免疫调节等作用而备受关注，但有关血根碱对断奶仔猪肠道黏膜屏障功能的影响及其机理有待研究。因此本项目拟通过体内和体外实验，研究其在LPS应激情况下，断奶仔猪肠道黏膜免疫性能、肠道黏膜屏障形态学以及肠道上皮细胞紧密连接和通透性的变化，并从血清和肠道细胞因子平衡以及TLR4/NF-κB信号通路等途径探讨其调控断奶仔猪肠道黏膜屏障保护功能及可能的作用机理，揭示其维护肠道黏膜屏障完整性和抗炎机制。研究结果将为寻找和探索新的维护肠道健康、减少仔猪断奶应激死亡率、替代和减少抗生素在饲料中的应用提供解决方案和理论基础。

断奶应激造成的肠道黏膜屏障受损是导致断奶仔猪肠道健康问题的主要原因，生产中常以添加抗生素和氧化锌作为缓解措施，而随之带来的食品安全及生态环境问题已引起世界范围内的高度关注，目前植物提取物作为极具潜力的替代方案已受到越来越的重视，其中血根碱因具有改善肠道健康、促进生长、降低肠道炎症及免疫调节等作用而备受关注。本项目通过体内和体外实验，研究其在LPS应激情况下，探讨了其维护肠道黏膜屏障完整性和抗炎机制，主要研究成果如下：1） 饲粮添加血根碱可以改善肠黏膜形态，提高小肠黏膜免疫功能，从而提高断奶仔猪的生长性能，达到与抗生素相当的效果；2）饲粮添加血根碱可以缓解断奶仔猪免疫应激导致的生长性能下降，提高血清IgG和IgM含量，抑制血清IL-1β、IL-6、TNF-α含量的增加和IL-10含量的降低，进而增强其免疫抵抗能力，缓解肠道通透性增加，改善小肠黏膜形态结构，从而使断奶仔猪的肠道健康得到改善；3）0.1 μg / mL血根对IPEC –J2细胞增殖具有显著促进作用, 抑制TLR4/NF-κB信号通路中相关mRNA和蛋白以及其下游炎症因子的表达；4) 项目共发表相关论文5篇，其中SCI论文3篇，一级学报2篇，培养研究生1名，本科生8名。