Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
Department of Animal Production, Faculty of Agriculture, Al-Azhar University, Nasr City, Cairo 11884, Egypt.
Int J Mol Sci. 2018 Feb 16;19(2):587. doi: 10.3390/ijms19020587.
Soybean agglutinin (SBA), is a non-fiber carbohydrate related protein and a major anti-nutritional factor. Integrins, transmembrane glycoproteins, are involved in many biological processes. Although recent work suggested that integrins are involved in SBA-induced cell-cycle alterations, no comprehensive study has reported whether integrins are involved in SBA-induced cell apoptosis (SCA) in IPEC-J2. The relationship between SBA and integrins are still unclear. We aimed to elucidate the effects of SBA on IPEC-J2 cell proliferation and cell apoptosis; to study the roles of integrins in IPEC-J2 normal cell apoptosis (NCA) and SCA; and to illustrate the relationship and connection type between SBA and integrins. Thus, IPEC-J2 cells were treated with SBA at the levels of 0, 0.125, 0.25, 0.5, 1.0 or 2.0 mg/mL to determine cell proliferation and cell apoptosis. The cells were divided into control, SBA treated groups, integrin inhibitor groups, and SBA + integrin inhibitor groups to determine the integrin function in SCA. The results showed that SBA significantly (p < 0.05) lowered cell proliferation and induced cell apoptosis in IPEC-J2 (p < 0.05). Inhibition of any integrin type induced the cell apoptosis (p < 0.05) and these integrins were involved in SCA (p < 0.05). Even SBA had no physical connection with integrins, an association was detected between SBA and α-actinin-2 ACTN2 (integrin-binding protein). Additionally, SBA reduced the mRNA expression of integrins by down regulating the gene expression level of ACTN2. We concluded an evidence for the anti-nutritional mechanism of SBA by ACTN2 with integrins. Further trials are needed to prove whether ACTN2 is the only protein for connecting SBA with integrin.
大豆凝集素（SBA）是一种非纤维碳水化合物相关蛋白，也是一种主要的抗营养因子。整合素是一种跨膜糖蛋白，参与许多生物学过程。虽然最近的研究表明整合素参与了 SBA 诱导的细胞周期改变，但尚无综合研究报道整合素是否参与了 IPEC-J2 中的 SBA 诱导的细胞凋亡（SCA）。SBA 与整合素之间的关系仍不清楚。我们旨在阐明 SBA 对 IPEC-J2 细胞增殖和细胞凋亡的影响；研究整合素在 IPEC-J2 正常细胞凋亡（NCA）和 SCA 中的作用；并阐明 SBA 与整合素之间的关系和连接类型。因此，用 0、0.125、0.25、0.5、1.0 或 2.0mg/ml 的 SBA 处理 IPEC-J2 细胞，以确定细胞增殖和细胞凋亡。将细胞分为对照组、SBA 处理组、整合素抑制剂组和 SBA+整合素抑制剂组，以确定 SCA 中整合素的功能。结果表明，SBA 显著（p<0.05）降低了 IPEC-J2 细胞的增殖并诱导了细胞凋亡（p<0.05）。抑制任何一种整合素类型都会诱导细胞凋亡（p<0.05），并且这些整合素参与了 SCA（p<0.05）。即使 SBA 与整合素没有物理连接，也检测到 SBA 与α-辅肌动蛋白-2（ACTN2，整合素结合蛋白）之间存在关联。此外，SBA 通过下调 ACTN2 的基因表达水平，降低了整合素的 mRNA 表达。我们得出结论，ACTN2 与整合素一起构成了 SBA 的抗营养机制。需要进一步的试验来证明 ACTN2 是否是连接 SBA 与整合素的唯一蛋白。
