miRNA Expression Analysis of IPEC-J2 Cells Damaged by Soybean 7S Globulin Reveals ssc-miR-221-5p as the Factor Alleviating Cell Damage

The most significant and sensitive antigen protein that causes diarrhea in weaned pigs is soybean 7S globulin. Therefore, identifying the primary target for minimizing intestinal damage brought on by soybean 7S globulin is crucial. MicroRNA (miRNA) is closely related to intestinal epithelium’s homeostasis and integrity. However, the change of miRNAs’ expression and the function of miRNAs in Soybean 7S globulin injured-IPEC-J2 cells are still unclear. In this study, the miRNAs’ expression profile in soybean 7S globulin-treated IPEC-J2 cells was investigated. Fifteen miRNAs were expressed differently. The differentially expressed miRNA target genes are mainly concentrated in signal release, cell connectivity, transcriptional inhibition, and Hedgehog signaling pathway. Notably, we noticed that the most significantly decreased miRNA was ssc-miR-221-5p after soybean 7S globulin treatment. Therefore, we conducted a preliminary study on the mechanisms of ssc-miR-221-5p in soybean 7S globulin-injured IPEC-J2 cells. Our research indicated that ssc-miR-221-5p may inhibit ROS production to alleviate soybean 7S globulin-induced apoptosis and inflammation in IPEC-J2 cells, thus protecting the cellular mechanical barrier, increasing cell proliferation, and improving cell viability. This study provides a theoretical basis for the prevention and control of diarrhea of weaned piglets.引发断奶仔猪腹泻的最主要且免疫敏感性最强的抗原蛋白为大豆7S球蛋白（soybean 7S globulin）。因此，明确可减轻大豆7S球蛋白所致肠道损伤的核心作用靶点具有重要研究价值。微小RNA（miRNA）与肠道上皮的稳态及完整性紧密相关，但大豆7S球蛋白损伤的IPEC-J2细胞中miRNA的表达变化及其功能仍有待阐明。本研究对大豆7S球蛋白处理后的IPEC-J2细胞的miRNA表达谱进行了探究，共鉴定出15个差异表达miRNA。差异表达miRNA的靶基因主要富集于信号释放、细胞连接、转录抑制以及Hedgehog信号通路。值得注意的是，经大豆7S球蛋白处理后，表达量下调最为显著的miRNA为ssc-miR-221-5p。据此，本研究针对ssc-miR-221-5p在大豆7S球蛋白损伤的IPEC-J2细胞中的作用机制开展了初步探索。研究结果表明，ssc-miR-221-5p可通过抑制活性氧（ROS）的产生，减轻大豆7S球蛋白诱导的IPEC-J2细胞凋亡与炎症反应，进而保护细胞机械屏障、促进细胞增殖并提升细胞活力。本研究为断奶仔猪腹泻的防控提供了理论基础。