靛玉红对ATP引起的巨噬细胞吞噬抑制、 ROS产生和细胞死亡的影响

为研究靛玉红对ATP引起的巨噬细胞免疫反应的影响, 采用中性红摄入法检测细胞吞噬功能, 用MTT法检测细胞活力, 通过DHE探针检测ROS的产生。结果表明: 细胞外ATP可抑制巨噬细胞吞噬、导致细胞死亡并促进ROS产生, 靛玉红对ATP引起的以上免疫反应有抑制作用。为了解靛玉红的作用机制, 进一步研究其对ATP引起的 Ca²⁺]_i 升高和P2X7受体介导的膜通透性增加的影响。结果显示: 靛玉红可降低ATP引起的 Ca²⁺]_i 升高, 抑制ATP诱发的EB进入。结果提示, 靛玉红对P2X7的活化有阻断作用, 其对ATP引起的免疫反应的抑制效果可能是通过抑制P2X7受体实现的。

Indirubin inhibits ATP-induced phagocytosis attenuation, ROS production and cell death of macrophages

This study is to investigate the effects of indirubin on ATP-induced immune responses of macrophages.  For this, neutral red dye uptake method was used to test phagocytosis, MTT assay was used for measuring cell death, and reactive oxygen species (ROS) was tested with fluorescent probe DHE.  The data showed that extracellular ATP attenuated phagocytosis, induced cell death and increased ROS production, and these effects were restored by pre-treating with indirubin.  This result suggested that indirubin blockade the effects of ATP on macrophages, because extracellular ATP-induced effects are dependent on P2 receptors, in particular P2X7 receptors.  Furthermore, the effects of indirubin on the activation of P2 receptors were tested, in particular P2X7 receptors.  The data showed that indirubin significantly decreased ATP-induced, P2 receptors mediated intracellular Ca²⁺ concentration ( Ca²⁺]_i ) rise and inhibited P2X7 receptor-based ethidium bromide (EB) dye uptake.  These results suggested the inhibitory effects of indirubin on the activation of P2X7 receptors, which may underlying the effects on ATP induced ROS production, phagocytosis attenuation and cell death of macrophages.