唾液酸乳糖对新生仔猪肠道屏障的保护作用与机制

母乳是新生仔猪最理想的食物来源，不仅含有其生长发育所需的各种常规营养成分，还含有大量能够调节和促进肠道发育的生物活性分子。唾液酸乳糖（SL）是近年从母猪乳汁中分离得到的一种三糖，由唾液酸和乳糖缩合而成，是乳汁中含量最丰富的寡糖之一，但其在新生仔猪生长发育中的作用尚不清楚。本项目拟通过给新生仔猪补充SL，考察对仔猪生产性能和肠道发育的影响；在此基础上，利用产肠毒素性大肠杆菌（ETEC）和内毒素（LPS）攻击模型，通过体内外研究探索SL是否通过干扰ETEC对肠上皮细胞的粘附、减少毒素产生并干扰其与配体（TLR4、Caspases）结合，进而缓解经IKKβ/NF-kB和Caspase信号介导的肠道上皮屏障炎性损伤。本项目的实施将进一步丰富母乳营养理论，拓展我们对母源性营养成分及其生物学功能的认识，也有望为新型代乳品研发和寻求改进新生仔猪生长发育的营养调控措施提供新的思路。

The breast milk is the best food for neonatal pigs. It not only contains sufficient conventional nutrients that support the growth of piglets, but also contains a number of bioactive substances that play a critical role in intestinal development. The siallyllactose (SL) is a novel trisaccharide isolated from the breast milk of lactating sows. It consists of one molecule of sialic acid and lactose, and is one of the most abundant oligosaccharides identified in the breast milk. However, the role of SL in the growth and development of piglets is unknown. In this study, we will investigate the influences of SL supplementation on growth performance and intestinal development in neonatal pigs. Moreover, the ETEC and LPS challenge model will be used to explore if the SL supplementation could attenuate the damage of intestinal epithelial barriers. Additionally, the molecular mechanisms behind the protective effects of SL supplementation will be explored. Particularly, we will investigate if the IKKβ/NF-kB and Caspase signaling pathways are involved in this biological process. This study will not only enriches the principle of “breastfeeding nutrition” and expands our understanding of the bioactive substances in the breast milk, but also offers a theoretical basis for developing novel milk replacers and nutritional strategies for neonatal pigs.