瘦素通过NLRP3炎性体对小鼠骨髓树突状细胞的作用及机制

Impact and mechanism of leptin on bone marrow-derived dendritic cells(BMDCs) via NLRP3 inflammasome

目的:探讨瘦素通过NLRP3炎性体对树突状细胞的作用及其机制。方法:体外诱导小鼠骨髓来源的树突状细胞(BMDCs),用不同浓度瘦素与BMDCs共同培养,分别检测培养上清IL-1β和IL-18的蛋白和基因水平,用FLICA试剂盒或ROS试剂盒分别在流式细胞仪上检测caspase-1活性或胞内ROS生成情况。瘦素与BMDCs共培养,加入caspase-1抑制剂或用siRNA干扰NLRP3基因表达,检测前后加入IL-1β和IL-18基因和蛋白表达水平。瘦素与BMDCs共培养,加入ROS抑制剂或KCL,检测加入前后IL-1β和IL-18蛋白分泌水平。结果:瘦素促进BMDCs分泌IL-1β和IL-18。瘦素通过上调NLRP3基因促进IL-1β和IL-18基因和蛋白表达,通过激活caspase-1蛋白提高IL-1β基因和蛋白水平,K^+外流参与此过程。结论:瘦素通过激活NLRP3炎性体促进BMDCs IL-1β和IL-18基因和蛋白表达,此过程部分通过K^+外流实现。这提示瘦素可能是NLRP3炎性体的激活剂。

Objective：To investigate the role and mechanism of leptin on dendritic cells by NLRP3 inflammasome. Methods： BMDCs were induced in vitro, leptin with scalar doses was cocuhured with BMDCs, IL-1β and IL-18 mRNA expression and protein secretion level were measured by q-RT-PCR and ELISA respectively. Caspase-1 activity or ROS synthesis were tested with FLICA kit or ROS detection assay kit on flow cytometry. IL-1β or IL-18 were detected after caspase-1 was inhibited by Ac-YVAD-cmk or NLRP3 was interfered by siRNA or ROS inhibitor DPI or KCL were added. Results： Leptin promoted secretion of IL-1β and IL-18. Leptin up- regulated NLRP3 and activted caspase-1 to secret proinflammtory cytokine,which K＋ efflux took part in. Conclusion： Leptin promotes secretion of IL-1β and IL-18 by activating NLRP3 infiammasome, and K＋ efflux takes part in this ,which hints us that leptin may be an activator of NLRP3 inflammasome.