硒对金黄色葡萄球菌感染的奶牛乳腺上皮细胞Nod2/MAPK/mTORs信号通路中关键因子mRNA转录水平的影响

The effect of Selenium on the transcriptional level of key factors in Nod2/MAPK/mTORs signaling pathways in S.aureus infected bovine mammary epithelial cells

为探究硒(Se)对金黄色葡萄球菌(S.aureus)感染的奶牛乳腺上皮细胞(bMECs) Nod2/MAPK/mTORs信号通路的调控机制,本研究首先用不同浓度硒(2μmol/L、4μmol/L和8μmol/L)对bMECs进行预孵育,12 h后再经S.aureus感染处理。分别于感染后6 h、8 h和10 h收集bMECs提取其RNA,应用q PCR方法检测bMECs中Nod2、RIP2、JNK、AKT、mTOR、IL-8和IL-10 mRNA的转录水平。结果显示,S.aureus能显著提高bMECs中Nod2、RIP2、JNK、AKT和mTOR mRNA的转录水平(p<0.01),而硒能不同程度的抑制这些因子mRNA的转录水平(p<0.05或p<0.01)。此外,S.aureus能显著或极显著提高bMECs中IL-8和IL-10 mRNA的转录水平(p<0.05或p<0.01),而硒对S.aureus感染的bMECs中IL-8和IL-10 mRNA的转录水平有明显抑制作用(p<0.05或p<0.01)。上述结果表明,硒可通过抑制Nod2/MAPK/mTORs信号通路的转导而减轻S.aureus诱导的bMECs的炎症反应。本研究为阐明硒能减轻S.aureus诱导的bMECs炎症反应的机制提供试验依据。

To study the regulation mechanism of Selenium(Se) on Nod2/MAPK/mTORs signaling pathway in the bovine mammary epithelial cells(bMECs) infected by S.aureus, bMECs were pre-incubated with different concentrations of Se(2 μmol/L,4 μmol/L and 8 μmol/L) for 12 h and then infected with S.aureus. bMECs were collected 6 h, 8 h and 10 h post S.aureus infection to extract total RNA. The transcriptional level of Nod2, RIP2, JNK, AKT, mTOR, IL-8 and IL-10 mRNA in bMECs were detected by qPCR. Results showed that S.aureus infection could significantly increase the mRNA transcriptional level of Nod2, RIP2, JNK,AKT and mTOR in bMECs(p<0.01). But Se could inhibit the mRNA transcriptional level of the above factors in different degrees(p<0.05 or p<0.01). In addition, S.aureus infection could also significantly increase the mRNA transcriptional level of IL-8 and IL-10 in bMECs(p<0.05 or p<0.01), but Se could significantly inhibit the mRNA transcriptional level of inflammatory cytokine IL-8 and IL-10 in S.aureus infected bMECs(p<0.05 or p<0.01). The above results suggested that Se could alleviate inflammatory reaction of bMECs induced by S.aureus by inhibiting the transduction of Nod2/MAPK/mTORs signaling pathway. This study will provide a theoretical basis for elucidating the specific mechanism of Se alleviating inflammation of bMECs induced by S.aureus.