吡格列酮促进大鼠骨髓内皮祖细胞的增殖

背景：内皮祖细胞具有增殖、迁移和分化为内皮细胞的特征，对冠状动脉硬化性心脏病及糖尿病心血管并发症的发生、发展可能起着重要作用。 目的：探讨选择性过氧化物酶体增殖物激活受体γ激动剂吡格列酮对大鼠骨髓内皮祖细胞增殖的影响及相关机制。 方法：①采用密度梯度离心法和差速贴壁法培养大鼠骨髓内皮祖细胞，置于含0，1，10，50，100，200 μmol/L吡格列酮的培养基中培养，观察吡格列酮促进内皮祖细胞增殖的最佳浓度。②将培养7 d的内皮祖细胞随机分5组：对照组加含二甲基亚砜的培养液；吡格列酮组加入50 μmol/L吡格列酮；PPAR-γ拮抗剂组加入50 μmol/L吡格列酮及10 μmol/L过氧化物酶体增殖物激活受体γ拮抗剂GW9662；PI3K/Akt阻滞剂组加入50 μmol/L吡格列酮及50 μmol/L磷脂酰肌醇3-激酶/蛋白激酶B通道阻滞剂Wortmannin；ERK阻滞剂组加入50 μmol/L吡格列酮及20 μmol/L细胞外调节蛋白激酶通道阻滞剂PD98059，观察不同组内皮祖细胞的增殖情况。 结果与结论：倒置显微镜下见培养前4 d细胞增殖不明显，第5-10天迅速增殖，并可见细胞集落及线状结构形成，第10天可达80%融合。培养第7天的内皮祖细胞具有吞噬Dil标记的乙酰化低密度脂蛋白和FITC标记的荆豆凝集素1的功能。10-200 μmol/L的吡格列酮均可明显促进内皮祖细胞的增殖(P < 0.01)，以50 μmol/L吡格列酮的作用最明显。进一步阻断相关信号通路发现，Wortmannin和GW9662可明显拮抗吡格列酮的促细胞增殖作用，而PD98059对吡格列酮的作用无影响。说明吡格列酮促进大鼠骨髓内皮祖细胞增殖的作用是通过磷脂酰肌醇3-激酶/蛋白激酶B信号通路介导的。

Pioglitazone promotes the proliferation of rat bone marrow endothelial progenitor cells

BACKGROUND:Endothelial progenitor cells are characterized by proliferation, migration and the ability to differentiate into endothelial cells and play an important role in the occurrence and development of coronary arteriosclerotic heart disease and diabetes mellitus and their complications. OBJECTIVE:To investigate the effects of selective peroxisome proliferative activated receptor γ excitomotor pioglitazone on the proliferation of rat bone marrow endothelial progenitor cells and the underlying mechanisms. METHODS:Using density gradient centrifugation and differential adherence methods, rat bone marrow endothelial progenitor cells were cultured in culture medium containing 0, 1, 10, 50, 100, 200 μmol/L pioglitazone and the optimal concentration of pioglitazone in promoting the proliferation of endothelial progenitor cells was determined. The endothelial progenitor cells cultured for 7 days were randomly divided into five groups: control group (dimethyl sulfoxide), pioglitazone group (50 μmol/L pioglitazone), peroxisome proliferative activated receptor γ antagon group (50 μmol/L pioglitazone+10 μmol/L peroxisome proliferative activated receptor γ antagon GW9662), phosphatidylinositol 3-kinase/Akt blocker group (50 μmol/L pioglitazone+50 μmol/L phosphatidylinositol 3-kinase/protein kinase B channel blocker Wortmannin), extracellular regulated protein kinase blocker group (50 μmol/L pioglitazone+20 μmol/L extracellular regulated protein kinase blocker PD98059). The proliferation of endothelial progenitor cells in each group was observed. RESULTS AND CONCLUSION:Through the inverted microscopy, cell proliferation was not obvious in the first 4 days of culture, peaked during 5-10 days, showing colony-forming units and line-like structure, and reached 80% confluency at 10 days. After 7 days of culture, endothelial progenitor cells could swallow DiL-ac-LDL and FITC-europaeus agglutinin-1. 10-200 μmol/L, particularly 50 μmol/L, pioglitazone could significantly promote the proliferation of endothelial progenitor cells (P < 0.01). Wortmannin and GW9662 could greatly antagonize pioglitazone promotion of cell proliferation, while PD98059 had no effects on the effects of pioglitazone. These findings suggest that pioglitazone promotes the proliferation of rat bone marrow endothelial progenitor cells via phosphatidylinositol 3-kinase/protein kinase B signaling pathway.