高糖对外周血内皮祖细胞数量和功能的影响

目的　观察高糖对外周血内皮祖细胞(EPCs)数量和功能的影响。方法　密度梯度离心法获取外周血单个核细胞 ,培养 7天后 ,收集贴壁细胞并加入不同浓度葡萄糖使培养液终浓度分别为 1 5、2 5、35和 4 5mmol/L ,并干预一定时间 (6、1 2、2 4和 4 8h)。多波长激光共聚焦显微镜鉴定FITC UEA Ⅰ和DiI acLDL双染色细胞为正在分化的EPCs,流式细胞仪检测其表面标志进一步鉴定EPCs,倒置荧光显微镜下计数。然后 ,分别采用MTT比色法、改良的Boyden小室、黏附能力测定实验和体外血管生成试剂盒分别观察EPCs的增殖、迁移、黏附和体外血管生成能力。结果　高糖呈量效和时效地减少外周血EPCs数量 ,4 5mmol/L浓度高糖作用 2 4h对EPCs数量的影响最为显著 (较对照组减少了近 1 / 2 ,P <0 0 1 )。高糖也显著抑制外周血EPCs的黏附、迁移、增殖和体外血管生成能力。结论　高糖可减少EPCs数量、抑制其功能 ,并呈浓度和时间依赖性

Effects of high glucose on number and activity of endothelial progenitor cells from peripheral blood

Objective To investigate the effect of high glucose on the number and proliferation, migration and adhesion of peripheral endothelial progenitor cells (EPCs). Methods Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin coated culture dishes. After 7 days of culture, several groups of attached cells were incubated with glucose in a series of concentrations (15, 25, 35, 45mmol/L) for different durations (6, 12, 24 and 48h). EPCs were characterized as adherent cells which were double positive for DiLDL uptake and lectin binding by direct fluorescent staining demonstrated under a laser scanning confocal microscope. EPCs were further documented by demonstrating the expression of KDR, VEGFR 2 and AC133 with flow cytometry. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with MTT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating MNCs on fibronectin coated dishes, and then the adherent cells were counted. Results Incubation of isolated human MNCs with high glucose concentration decreased the number of EPCs, and this effect was most prominant when glucose concentration was 45mmol/L, and incubated for 24 hours (approximately 1 fold decrease, P <0 01). In addition, high glucose inhibited proliferative, migratory, adhesive and in vitro vasculogenesis capacities of EPC in a time and dose dependent manner. Conclusion The results suggested that high glucose might inhibit EPCs augmentation and decrease its functional activity.