Department of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Science, Japan.
Am J Physiol Cell Physiol. 2012 Mar 15;302(6):C892-901. doi: 10.1152/ajpcell.00380.2011. Epub 2011 Dec 7.
Circulating endothelial progenitor cells (EPCs) derived from the bone marrow (BM) participate in maintaining endothelial integrity and vascular homeostasis. Reduced EPC number and function result in vascular complications in diabetes. EPCs are a population of cells existing in various differentiation stages, and their cell surface marker profiles change during the process of mobilization and maturation. Hence, a generally accepted marker combination and a standardized protocol for the quantification of EPCs remain to be established. To determine the EPC subsets that are affected by diabetes, we comprehensively analyzed 32 surface marker combinations of mouse peripheral blood (PB), BM, and spleen cells by multicolor flow cytometry. Ten subsets equivalent to previously reported mouse EPCs significantly declined in number in the PB of streptozotocin-induced diabetic mice, and this reduction was reversed by insulin treatment. The PI(-)Lin(-)c-Kit(-)Sca-1(+)Flk-1(-)CD34(-)CD31(+) EPC cluster, which can differentiate into mature endothelial cells in vitro, was the highest population in the PB, BM, and spleen and occurred 61 times more in the spleen than in the PB. The cell number significantly decreased in the BM as well as in the PB but paradoxically increased in the spleen under diabetic conditions. Insulin treatment reversed the decrease of EPC subsets in the BM and PB and reversed their increase in spleen. A similar tendency was observed in some of the major cell populations in db/db mice. To the best of our knowledge, we are the first to report spatial population changes in mouse EPCs by diabetes in the blood and in the BM across the spleen. Diminished circulating EPC supply by diabetes may be ascribed to impaired EPC production in the BM and to decreased EPC mobilization from the spleen, which may contribute to vascular dysfunction in diabetic conditions.
循环内皮祖细胞 (EPC) 来源于骨髓 (BM)，参与维持内皮完整性和血管内稳态。EPC 数量和功能减少会导致糖尿病的血管并发症。EPC 是一群处于不同分化阶段的细胞，其细胞表面标志物谱在动员和成熟过程中发生变化。因此，需要建立一个普遍接受的标志物组合和标准化方案来定量 EPC。为了确定受糖尿病影响的 EPC 亚群，我们通过多色流式细胞术全面分析了 32 种小鼠外周血 (PB)、BM 和脾细胞的表面标志物组合。10 个与先前报道的小鼠 EPC 等效的亚群数量在链脲佐菌素诱导的糖尿病小鼠的 PB 中显著减少，胰岛素治疗可逆转这种减少。PI(-)Lin(-)c-Kit(-)Sca-1(+)Flk-1(-)CD34(-)CD31(+)EPC 簇在体外可分化为成熟的内皮细胞，在 PB、BM 和脾中是最高的群体，在脾中的出现频率比 PB 中高 61 倍。在糖尿病条件下，BM 和 PB 中的细胞数量显著减少，但脾中却异常增加。胰岛素治疗可逆转 BM 和 PB 中 EPC 亚群的减少，并逆转其在脾中的增加。在 db/db 小鼠的一些主要细胞群中也观察到类似的趋势。据我们所知，我们是第一个报道糖尿病在血液和 BM 中引起小鼠 EPC 空间群体变化的，并且在脾中也有变化。糖尿病导致循环 EPC 供应减少可能归因于 BM 中 EPC 生成受损以及从脾中动员 EPC 减少，这可能导致糖尿病条件下的血管功能障碍。
