右美托咪定通过JAK2/STAT3信号通路影响肺泡巨噬细胞极化

Dexmedetomidine affects alveolar macrophage polarization through JAK2/STAT3 signaling pathway

目的:研究右美托咪定(DEX)对脂多糖(LPS)诱导的肺泡巨噬细胞极化的影响,并探讨其相关机制。方法:体外培养大鼠肺泡巨噬细胞NR8383,实验1:对照组、模型组(1μg/ml LPS)、DEX低、中、高剂量组(1、5、10 mg/kg DEX+1μg/ml LPS);实验2:DEX高剂量组(10 mg/kg)、DEX高剂量+Colivelin(JAK2/STAT3信号通路激活剂)组(10 mg/kg DEX+0.5μmol/L Colivelin)。倒置显微镜观察大鼠肺泡巨噬细胞NR8383形态学变化;RT-PCR检测NR8383细胞中iNOS与Arg1 mRNA表达水平;流式细胞术检测NR8383细胞中CD86、CD163蛋白表达水平;Western blot检测NR8383细胞表面标志物蛋白TNF-α、iNOS、SOCS、Arg1、TGF-β及JAK2/STAT3信号通路相关蛋白表达水平变化。结果:与对照组比较,模型组NR8383细胞间隙有大量细胞碎片,iNOS mRNA、CD86阳性细胞比例、TNF-α、p-JAK2/JAK2、p-STAT3/STAT3蛋白表达水平显著升高,Arg1 mRNA、CD163阳性细胞比例、SOCS、TGF-β表达水平显著降低(P<0.05);与模型组相比,DEX低、中、高剂量组NR8383细胞间隙细胞碎片减少,iNOS mRNA、CD86阳性细胞比例、TNF-α、p-JAK2/JAK2、p-STAT3/STAT3蛋白表达水平显著降低,Arg1 mRNA、CD163阳性细胞比例、SOCS、TGF-β表达水平显著升高(P<0.05)。Colivelin对JAK2/STAT3信号通路再激活可减弱DEX对LPS诱导的NR8383细胞极化作用。结论:DEX抑制LPS诱导的NR8383细胞M1型极化,可能是通过抑制JAK2/STAT3信号通路实现的。

Objective:To investigate the effect of dexmedetomidine(DEX)on the polarization of alveolar macrophages in⁃duced by lipopolysaccharide(LPS)and to explore the related mechanisms.Methods:Rat alveolar macrophages NR8383 were cul⁃tured in vitro.Experiment one was divided into control group,model group(1μg/ml LPS),DEX low,medium and high dose groups(1,5,10 mg/kg DEX+10 mg/kg LPS).Experiment two was divided into DEX high dose group(10 mg/kg)and DEX high dose+Colive⁃lin(JAK2/STAT3 signaling pathway activator)group(10 mg/kg DEX+0.5μmol/L Colivelin).The morphological changes of rat alveo⁃lar macrophages NR8383 were observed by inverted microscope;RT-PCR method was used to detect the expression levels of iNOS and Arg1 mRNA in NR8383 cells,and flow cytometry was used to detect the expression levels of CD86 and CD163 proteins in NR8383 cells;Western blot was used to detect the expression levels of surface marker proteins TNF-α,iNOS,SOCS,Arg1,TGF-βand JAK2/STAT3 signaling pathway related proteins in NR8383 cells.Results:Compared with control group,there were a lot of cell debris in the intercellular space of NR8383 in the model group,the proportions of iNOS mRNA,CD86 positive cells,and the expression levels of TNF-α,p-JAK2/JAK2,p-STAT3/STAT3 were significantly increased,the proportions of Arg1 mRNA,CD163 positive cells,and the expression levels of SOCS and TGF-βwere significantly reduced(P<0.05);compared with the model group,the NR8383 intercellular cell debris in the DEX low,medium,and high dose groups were decreased,the proportions of iNOS mRNA,CD86 positive cells,and the expression levels of TNF-α,p-JAK2/JAK2,p-STAT3/STAT3 were significantly reduced,the proportions of Arg1 mRNA,CD163 positive cells,and the expression levels of SOCS and TGF-βwere significantly increased(P<0.05).The reactivation of the JAK2/STAT3 signal pathway by Colivelin could weaken the role of DEX in LPS induced NR8383 cell polarization.Conclusion:DEX can inhibit the M1 polarization of NR8383 cells induced by LPS,which may be achieved by inhibiting the JAK2/STAT3 signaling pathway.