热应激对猪PBMC中NOD样受体及炎性因子mRNA转录水平的影响

Effect of heat stress on NOD like receptor and inflammatory cytokines mRNA transcriptional level in peripheral blood mononuclear cell of pigs

NOD样受体是重要的天然免疫识别受体,其与革兰氏阳性菌的肽多糖等配体结合后,能够诱导多种炎性因子的表达,参与多种疫病的调控。为探究NOD样受体是否参与了热应激致病过程,本研究选取2月龄(15±1 kg)土杂猪12头,随机分为对照组和热应激组,并在热应激的第0、7 d、14 d和21 d的4个时间点采集其外周血,分离外周血单核细胞(PBMC)。荧光定量PCR检测了PBMCs中NOD1、NOD2及炎性因子TNF-α、IFN-γ、IL-6、IL-10和IL-1βmRNA的转录水平。结果显示,与对照组相比,NOD1和NOD2 mRNA转录水平在热应激的第7 d和14 d显著上调(p<0.01),但在第21 d时显著下调(p<0.05)。炎性因子TNF-α、IFN-γmRNA转录水平在热应激的第7 d、14 d、21 d显著上调(p<0.05),IL-10 m RNA转录水平在热应激的第14 d、 21 d显著上调(p<0.05),IL-1βm RNA转录水平在热应激的第7 d和14 d极显著上调(p<0.01),在21 d时显著下调(p<0.01)。IL-6mRNA转录水平在热应激的第7 d显著上调(p<0.05),14 d差异不显著,21 d时极显著下调(p<0.01)。研究表明热应激后短期内显著上调猪PBMC中NOD1、NOD2及炎性因子的转录水平,这为进一步阐述热应激的致病过程提供了依据。

NOD-like receptor is an important innate immune recognizing receptor.At the point when binding with a ligand such as peptidoglycan of Gram-positive bacteria,which induces the expression of various inflammatory factors and participate in the direction of different diseases.In order to understand whether NOD-like receptor take part in the regulation of heat stress induced diseases,twelve 2 months old pigs(weighing 15±1 kg),were randomly divided into two groups,a heat stress group(rearing in a 35±1℃)and a control group(rearing in a 20±2℃).And the blood samples were collected by anterior vena cava puncture in the morning of day 0,7,14 and 21 after heat stress began.The transcriptional levels of NOD1 and NOD2 mRNA,inflammatory cytokines of TNF-α,IFN-γ,IL-6,IL-10 and IL-1βmRNA in peripheral blood mononuclear cell(PBMCs)were detected by RT-qPCR.The results showed that transcriptional levels of NOD1/2 mR NA were up-regulated in heat-stressed pigs than that in control at day 7 and 14(p<0.01),but a significant decrease was detected on the day 21(p<0.05).The transcriptional levels of inflammatory cytokines,such as TNF-α,and IFN-γ,were significantly increased in heat-stressed pigs than that in control at day 7,14 and 21(p<0.05).There was no distinction about IL-10 at days 7,but a drastic increase in heat stressed pigs were detected at day 14 and 21(p<0.05).IL-1βmRNA transcriptional levels was increased significantly in heat-stressed pigs on the day 7 and 14(p<0.01),but decreased on the day 21(p<0.01).IL-6 mRNA transcriptional levels was increased significantly in heat-stressed pigs on the day 7(p<0.05),but decreased significantly on the day 21(p<0.01).The results showed that heat stress up-regulated NOD1/2 and inflammatory cytokines in PBMCs of pigs,the present study facilitated to clarify the mechanism of heat stress induced diseases.