糖基化终末产物对人外周血内皮祖细胞生物学特性的影响

目的 观察糖基化终末产物(AGEs)对体外培养的人外周血内皮祖细胞(EPCs)生物学特性的影响.方法 以密度梯度离心法获取人外周血单个核细胞(MNCs),由激光共聚焦显微镜鉴定FITC-UEA-1和Dil-acLDL双染色阳性细胞为正在分化的EPCs.加入不同浓度AGEs培养48h,然后分别采用MTT法、Boyden小室测定来观察EPCs的增殖、迁移能力;以人纤维连接蛋白(hFN)检测EPCs的黏附能力;分别采用甲醛和Dnase Ⅰ诱导EPCs凋亡作为阳性对照组,用AnnexinV-FITC/PI和TUNEL法流式细胞仪检测AGEs对EPCs凋亡率的影响.结果 高浓度AGEs可减少EPCs贴壁细胞数量(P<0.01),明显减弱EPCs的黏附(P<0.01)、增殖(P<0.001)、迁移能力(P<0.05),提高EPCs的早期凋亡率(P<0.001).结论 AGEs可减少EPCs的数昔并使EPCs的功能受损.

Effects of advanced glycation end products on endothelial progenitor cells in the blood

Objective In addition to be involved in the angiogenesis, endothelial progenitor cells (EPCs) have roles in endothelium repairing, wound healing, and for protecting blood vessels from restenosis, Advanced glycation end products (AGEs) facilitate the development and progression of atherosclerosis, diabetes associated vascular complications and uremia through various mechanisms such as damaging the endothelium, promoting leukocyte adhension, increasing the aggregation of platelets, and stimulating the proliferation of vascular smooth muscles. This study was designed to explore whether AGEs have effects on biological characteristics of EPCs in cultured human peripheral blood cells. Methods Total mononuclear cells (MNCs), isolated from human peripheral blood by density gradient centrifugatian and adherence cells filtration, were incuba-ted in fibronectin-coated culture dishes. Endothelial cells were identified by means of the adsorption of ulex eurepaeus-aggluti-nin- Ⅰ (UEA- Ⅰ) labelled with fluorescein isothiacyanate (FITC) and Dil-acLDL internalization. Four days later,various con-centrations of AGEs were added to the adherent cells and remained for48 hours. MTT assay and Boyden chamber were used for observing the proliferation and migration of EPCs. Human fibronectin was used to examine the adhesion ability of EPCs. Apop-tosis was induced in the EPCs with formaldehyde and Dnase Ⅰ as a positive control group. Annexin V-FITC/PI and TUNEL method of flow cytometry were used for evaluating the effects of AGEs on the rate of apeptosis in the EPCs. Results AGEs at high concentration decreased the number of EPCs independently (P < 0.01) ; reduced the proliferation (P < 0.01), migration (P<0.001) and adhesive capacity (P<0.05) of EPCs significantly,as well as increasing the apoptasis rate of EPCs in the early stage (P < 0.001). Conclusion AGEs may have adverse effects on EPCs from cultured human peripheral MNCs, such as decreasing their numbers and impairing their functions.