奶牛低血钙症降低中性粒细胞上ORAI1蛋白的表达

Cows with hypocalcemia result in the expression decrease of ORAI1 protein on neutrophils

旨在研究泌乳初期高产奶牛高发的低血钙症是否影响细胞内Ca2+通路进而影响中性粒细胞活性并增加泌乳初期的炎症反应。尾静脉肝素抗凝采集血液分离中性粒细胞(PMN),采用Western blot检测ORAI1蛋白的表达,利用流式细胞仪测定静息状态下、离子霉素刺激的中性粒细胞表面ORAI1蛋白丰度以及ROS水平。结果显示,健康对照组奶牛中性粒细胞表面ORAI1蛋白丰度与表达水平均显著高于低血钙症试验组。低血钙症中性粒细胞经离子霉素刺激后细胞表面ORAI1蛋白丰度显著高于未经刺激的低血钙症PMN。健康对照组奶牛中性粒细胞中的ROS水平显著低于低血钙症试验组。这些结果表明,奶牛低血钙症降低中性粒细胞内钙离子进入的调控,以及低血钙症能降低中性粒细胞内的ROS水平,导致泌乳初期的炎症反应。

The aim of this study was to investigate whether the hypocalcemia of high production cows during early lactation affects intracellular Ca2+ pathway,thus affects the activity of neutrophils to increase the inflammatory response in the early stage of lactation.Neutrophils(PMN) were isolated from the tail vein.Expression of ORAI1 protein was measured by Western blot.Flow cytometry was used to determine the surface abundance and ROS of ionomycin stimulated neutrophils ORAI1 protein in resting state.The results showed the expression and abundance of ORAI1 protein in neutrophils in the healthy control group was significantly higher than that of hypocalcemia group.The abundance of ORAI1 protein with ionomycin treatment was significantly higher than without ionomycin treatment in the hypocalcemia group.The expression level of ROS in neutrophils of dairy cows in the healthy control group was significantly lower than that of the hypocalcemia group.These results indicated that hypocalcemia reduce the regulation of intracellular calcium entry in neutrophils,and reduce ROS expression in neutrophils,resulting in early inflammatory response during lactation.