海分枝杆菌调控巨噬细胞糖酵解重编程的研究

Reprogramming of macrophage glycolysis by Macobacterium marinum

目的:通过检测海分枝杆菌感染巨噬细胞后糖酵解相关基因的表达和代谢产物乳酸的变化情况探究海分枝杆菌对巨噬细胞糖酵解的调控。方法:利用实时荧光定量PCR检测不同感染条件下海分枝杆菌感染巨噬细胞后糖酵解代谢相关基因(SLC2A1、HK2、LDHA)的表达,同时检测糖酵解代谢最终产物乳酸的浓度。使用流式细胞仪和(或)共聚焦显微镜检测不同感染条件下巨噬细胞内葡萄糖摄取情况以及细胞内海分枝杆菌的荧光强度。结果:海分枝杆菌感染增加了巨噬细胞对葡萄糖的摄取,并以感染时间和感染复数依赖的方式促进巨噬细胞糖酵解代谢相关基因(SLC2A1、HK2、LDHA)的表达和乳酸的产生。与热灭活的海分枝杆菌相比,活的海分枝杆菌抑制糖酵解相关基因(SLC2A1、HK2、LDHA)的表达和乳酸的产生。此外,使用2-脱氧葡萄糖抑制糖酵解代谢酶HK2的活性促进了细胞内海分枝杆菌的存活。结论:糖酵解重编程是巨噬细胞对海分枝杆菌感染的免疫防御机制之一,而海分枝杆菌可通过调控巨噬细胞糖酵解促进自身在胞内的存活。因此,通过调控巨噬细胞的糖酵解可能是控制海分枝杆菌感染的潜在干预措施。

Objective:To investigate the reprogramming of macrophage glycolysis by Macobacterium marinum(M.marinum)by measuring the expression of glycolysis-relared genes and the changes of the concentration of lactic acid after M.marinum infection.Methods:The expression of glycolysis-related genes(SLC2A1,HK2,LDHA)were measured by Real-time quantitative PCR in M.marinum infected macrophage under the different conditions,and the concentration of lactic acid,the final product of glycolysis,was also detected.The uptake of glucose and the fluorescence intensity of M.marinum under the different conditions were measured by flow cytometry and/or confocal microscopy.Results:M.marinum infection increased glucose uptake by macrophage,and promoted the expression of glycolysis-related genes(SLC2A1,HK2,LDHA)and lactic acid production in a multiplicity of infection and time denpendent way.Compared to the heat-killed M.marinum,live M.marinum inhibited the expression of glycolysis-related genes(SLC2A1,HK2,LDHA)and the production of lactic acid.In addition,2-deoxyglucose,the inhibitor of glycolytic enzyme HK2,promoted the survival of intracellular M.marinum.Conclusion:Reprogramming of glycolysis is one of the immune defense mechanisms of macrophage against M.marinum and M.marinum can promote their survival in macrophage by regulating macrophage glycolysis.Thus,regulation of macrophage glycolysis may be a potential intervention to control M.marinum infection.