Li Shuaichen, Ding Jiafeng, Jiang Lihong, Hayat Muhammad Abid, Song Qiaozhi, Li Yuepeng, Zhang Xianhao, Zhang Jiantao
College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, Harbin, China.
Front Vet Sci. 2020 Apr 21;7:211. doi: 10.3389/fvets.2020.00211. eCollection 2020.
Alimentary oligofructose (OF) overload can induce several diseases in cattle, such as ruminal acidosis, laminitis, and synovitis. The role of blood polymorphonuclear neutrophil (PMN) remains unclear during OF overload. The aim of this study was to investigate the dynamic changes in reactive oxygen species (ROS) production and the expression profile of genes in blood PMN in a model of OF overload. Twelve clinically healthy and non-pregnant Chinese Holstein heifers, aged between 18 and 26 mo, weighing 335-403 kg, BCS (5-point scale) ranges 2.7-3.3 were used for the experiments. OF heifers ( = 6) received 17 g/kg of BW oligofructose dissolved in 2 L/100 kg of BW tap water and the CON heifers ( = 6) received 2 L/100 kg of BW tap water. Blood PMN was isolated for each heifer 0, 6, 12, 18, 24, 36, 48, 60, and 72 h after administration. PMN was analyzed either by endogenous and phorbol myristate acetate (PMA)-induced ROS production or by quantitative real-time PCR. After 12 h, PMA-induced ROS production decreased, which was sustained until 48 h. The expressions of inflammation markers (IL1α, IL1β, IL6, IL10, TNFα, STAT3, TLR4, MMP9, and HP) and eicosanoids (ALOX5, ALOX5AP, and PLA2G4A) were upregulated. The expression of adhesion and migration (CXCR2, CXCL8, CD62L, ITGA4, ITGAM, and ITGB2) in OF heifers was increased compared with CON heifers. The expression of oxidative stress (SOD2 and S100A8) was upregulated, while SOD1 and MPO were downregulated. In metabolism and receptor genes, the expressions of GRα and INSR decreased after 12 h, while Fas increased until 6 h and then decreased at 18 h. The expression of LDHA and PANX1 did not show any differences after OF overload. These findings indicate that OF overload induced systemic activation of PMN, which provides a step toward a better understanding of the role of innate immune responses in response to oral OF administration.
日粮低聚果糖（OF）过量会诱发奶牛的多种疾病，如瘤胃酸中毒、蹄叶炎和滑膜炎。在OF过量期间，血液多形核中性粒细胞（PMN）的作用仍不清楚。本研究的目的是在OF过量模型中研究血液PMN中活性氧（ROS）产生的动态变化和基因表达谱。选用12头18至26月龄、体重335 - 403千克、体况评分（5分制）在2.7 - 3.3之间的临床健康非妊娠中国荷斯坦青年母牛进行实验。OF组母牛（n = 6）接受按体重17克/千克的低聚果糖溶解于每100千克体重2升的自来水中，对照组母牛（n = 6）接受每100千克体重2升的自来水。在给药后0、6、12、18、24、36、48、60和72小时，为每头母牛分离血液PMN。通过内源性和佛波酯（PMA）诱导的ROS产生或定量实时PCR分析PMN。12小时后，PMA诱导的ROS产生下降，并持续到48小时。炎症标志物（IL1α、IL1β、IL6、IL10、TNFα、STAT3、TLR4、MMP9和HP）和类花生酸（ALOX5、ALOX5AP和PLA2G4A）的表达上调。与对照组母牛相比，OF组母牛中黏附与迁移相关基因（CXCR2、CXCL8、CD62L、ITGA4、ITGAM和ITGB2）的表达增加。氧化应激相关基因（SOD2和S100A8）的表达上调，而SOD1和MPO下调。在代谢和受体基因方面，12小时后GRα和INSR的表达下降，而Fas在6小时前增加，然后在18小时下降。OF过量后LDHA和PANX1的表达没有显示出任何差异。这些发现表明，OF过量诱导了PMN的全身激活，这为更好地理解先天免疫反应在口服OF给药反应中的作用迈出了一步。
