Qi Jiawen, Yu Bing, Hu Youjun, Luo Yuheng, Zheng Ping, Mao Xiangbing, Yu Jie, Zhao Xiaonan, He Taiqian, Yan Hui, Wu Aimin, He Jun
Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China.
Key Laboratory of Animal Disease-Resistant Nutrition, Chengdu 611130, China.
Animals (Basel). 2024 Aug 19;14(16):2405. doi: 10.3390/ani14162405.
The study was designed to investigate the protective effect of dietary supplementation with coated benzoic acid (CBA) on intestinal barrier function in weaned pigs challenged with enterotoxigenic (ETEC). Thirty-two pigs were randomized to four treatments and given either a basal diet or a basal diet supplemented with 3.0 g/kg CBA, followed by oral administration of ETEC or culture medium. The results showed that CBA supplementation increased the average daily weight gain (ADWG) in the ETEC-challenged pigs ( < 0.05). CBA also increased the serum activity of total superoxide dismutase (T-SOD) and the total antioxidant capacity (T-AOC), as it decreased the serum concentrations of endotoxin, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the ETEC-challenged pigs ( < 0.05). Interestingly, the CBA alleviated the ETEC-induced intestinal epithelial injury, as indicated by a reversal of the decrease in D-xylose absorption and a decrease in the serum levels of D-lactate and diamine oxidase (DAO) activity, as well as a decrease in the quantity of apoptotic cells in the jejunal epithelium following ETEC challenge ( < 0.05). Moreover, CBA supplementation significantly elevated the mucosal antioxidant capacity and increased the abundance of tight junction protein ZO-1 and the quantity of sIgA-positive cells in the jejunal epithelium ( < 0.05). Notably, CBA increased the expression levels of porcine beta defensin 2 (), , and nuclear factor erythroid-2 related factor 2 (), while downregulating the expression of toll-like receptor 4 () in the jejunal mucosa ( < 0.05). Moreover, CBA decreased the expression levels of interleukin-1β (), myeloid differentiation factor 88 (), and nuclear factor-kappa B () in the ileal mucosa upon ETEC challenge ( < 0.05). These results suggest that CBA may attenuate ETEC-induced damage to the intestinal epithelium, resulting in reduced inflammation, enhanced intestinal immunity and antioxidant capacity, and improved intestinal epithelial function.
本研究旨在探讨日粮添加包膜苯甲酸（CBA）对产肠毒素大肠杆菌（ETEC）攻毒断奶仔猪肠道屏障功能的保护作用。32头仔猪随机分为4组，分别给予基础日粮或添加3.0 g/kg CBA的基础日粮，随后口服ETEC或培养基。结果表明，添加CBA可提高ETEC攻毒仔猪的平均日增重（ADWG）（P<0.05）。CBA还提高了总超氧化物歧化酶（T-SOD）的血清活性和总抗氧化能力（T-AOC），同时降低了ETEC攻毒仔猪血清中内毒素、白细胞介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）的浓度（P<0.05）。有趣的是，CBA减轻了ETEC诱导的肠道上皮损伤，表现为D-木糖吸收减少的逆转、血清D-乳酸水平和二胺氧化酶（DAO）活性降低，以及ETEC攻毒后空肠上皮细胞凋亡数量减少（P<0.05）。此外，添加CBA显著提高了黏膜抗氧化能力，增加了紧密连接蛋白ZO-1的丰度和空肠上皮中分泌型免疫球蛋白A（sIgA）阳性细胞的数量（P<0.05）。值得注意的是，CBA增加了空肠黏膜中猪β-防御素2（pBD-2）、SOD和核因子红细胞2相关因子2（Nrf2）的表达水平，同时下调了Toll样受体4（TLR4）的表达（P<0.05）。此外，ETEC攻毒后，CBA降低了回肠黏膜中白细胞介素-1β（IL-1β）、髓样分化因子88（MyD88）和核因子κB（NF-κB）的表达水平（P<0.05）。这些结果表明，CBA可能减轻ETEC对肠道上皮的损伤，从而减少炎症，增强肠道免疫和抗氧化能力，并改善肠道上皮功能。
