Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China.
Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, USA.
Biol Trace Elem Res. 2018 Dec;186(2):505-513. doi: 10.1007/s12011-018-1333-y. Epub 2018 Apr 18.
This study was conducted to profile selenoprotein encoding genes in mouse RAW264.7 cells upon lipopolysaccharide (LPS) challenge and integrate their roles into immunological regulation in response to selenium (Se) pretreatment. LPS was used to develop immunological stress in macrophages. Cells were pretreated with different levels of Se (0, 0.5, 1.0, 1.5, 2.0 μmol Se/L) for 2 h, followed by LPS (100 ng/mL) stimulation for another 3 h. The mRNA expression of 24 selenoprotein encoding genes and 9 inflammation-related genes were investigated. The results showed that LPS (100 ng/mL) effectively induced immunological stress in RAW264.7 cells with induced inflammation cytokines, IL-6 and TNF-α, mRNA expression, and cellular secretion. LPS increased (P < 0.05) mRNA profiles of 9 inflammation-related genes in cells, while short-time Se pretreatment modestly reversed (P < 0.05) the LPS-induced upregulation of 7 genes (COX-2, ICAM-1, IL-1β, IL-6, IL-10, iNOS, and MCP-1) and further increased (P < 0.05) expression of IFN-β and TNF-α in stressed cells. Meanwhile, LPS decreased (P < 0.05) mRNA levels of 18 selenoprotein encoding genes and upregulated mRNA levels of TXNRD1 and TXNRD3 in cells. Se pretreatment recovered (P < 0.05) expression of 3 selenoprotein encoding genes (GPX1, SELENOH, and SELENOW) in a dose-dependent manner and increased (P < 0.05) expression of another 5 selenoprotein encoding genes (SELENOK, SELENOM, SELENOS, SELENOT, and TXNRD2) only at a high level (2.0 μmol Se/L). Taken together, LPS-induced immunological stress in RAW264.7 cells accompanied with the global downregulation of selenoprotein encoding genes and Se pretreatment alleviated immunological stress via upregulation of a subset of selenoprotein encoding genes.
本研究旨在描绘脂多糖（LPS）刺激后 RAW264.7 细胞中硒蛋白编码基因的表达谱，并整合其在硒（Se）预处理应答中的免疫调节作用。LPS 用于诱导巨噬细胞产生免疫应激。细胞用不同浓度（0、0.5、1.0、1.5、2.0 μmol Se/L）Se 预处理 2 小时，然后用 LPS（100ng/mL）刺激 3 小时。检测 24 个硒蛋白编码基因和 9 个炎症相关基因的 mRNA 表达情况。结果表明，100ng/mL LPS 可有效诱导 RAW264.7 细胞产生免疫应激，诱导炎症细胞因子 IL-6 和 TNF-α的 mRNA 表达和细胞分泌。LPS 增加了细胞中 9 个炎症相关基因的 mRNA 谱（P<0.05），而短期 Se 预处理则适度逆转了 LPS 诱导的 7 个基因（COX-2、ICAM-1、IL-1β、IL-6、IL-10、iNOS 和 MCP-1）的上调（P<0.05），并进一步增加了应激细胞中 IFN-β和 TNF-α的表达（P<0.05）。同时，LPS 降低了细胞中 18 个硒蛋白编码基因的 mRNA 水平，并上调了 TXNRD1 和 TXNRD3 的 mRNA 水平。Se 预处理以剂量依赖的方式恢复了 3 个硒蛋白编码基因（GPX1、SELENOH 和 SELENOW）的表达，并仅在高浓度（2.0 μmol Se/L）下增加了另外 5 个硒蛋白编码基因（SELENOK、SELENOM、SELENOS、SELENOT 和 TXNRD2）的表达（P<0.05）。综上所述，LPS 诱导 RAW264.7 细胞产生免疫应激，同时下调硒蛋白编码基因的表达，Se 预处理通过上调部分硒蛋白编码基因缓解免疫应激。
