中文摘要：

为探讨apelin促进脂肪间充质干细胞增殖分化及其相关机制的分子影像研究方法,用酶消化法分离β-actin-luc FVB转基因小鼠的脂肪间充质干细胞（AD-MSCs）,流式细胞术鉴定干细胞标志,生物发光成像确定细胞荧光素酶的表达。建立缺氧（H）6 h/复氧（R）2 h细胞模型,分3组：对照组、缺氧/复氧组（H/R）和H/R＋apelin干预组（10-10～10-5 mol/L）。MTT法和生物发光成像测定各组细胞增殖率,免疫印迹法检测细胞内激酶磷酸化Akt的表达。流式细胞术结果显示脂肪间充质干细胞表达CD44及CD90,而且荧光素酶的表达与细胞数量呈线性相关。在缺氧环境中,apelin的干预可显著促进AD-MSCs的增殖。Western blot检测发现,pAkt的表达在apelin干预组明显高于对照组（P〈0.05）。说明apelin可通过Akt信号途径促进脂肪来源间充质干细胞的增殖,抑制缺氧诱导的凋亡发生,为干细胞的替代治疗提供新的辅助治疗靶点。

英文摘要：

Apelin,a novel peptide with significant cardioactive properties,has various beneficial effects on vascular protection.This study was designed to evaluate the contribution of apelin to the therapeutic efficacy of mesenchymal stem cells under ischemia.Adipose derived mesenchymal stem cells（AD-MSCs） stablely expressing firefly luciferase（Fluc） were isolated from β-actin-luc transgenic mice and characterized by flow cytometry and bioluminescence imaging（BLI）.AD-MSCs were subjected to normal control,hypoxia 6 h ＋ reoxygen 2 h（H/R） and H/R＋apelin（10-10~10-5 mol/L）.Cell survival and proliferation were assessed by BLI and MTT assay.The expressions of Akt and pAkt after apelin administration were analyzed by Western blot.It was found that AD-MSCs were positive for the CD44 and CD90 by flow cytometry.The firefly luciferase expression was well correlated with cell numbers which proved by both BLI and luciferase assay.Administration of apelin increased proliferation of AD-MSCs under hypoxia compared with control groups.Western blot assay revealed the phosphorylation of Akt was higher in apelin group than that in control groups.The results suggested that apelin has beneficial effects on the proliferation and survival of mesenchymal stem cells under hypoxia and might constitute an important therapy target in stem cell therapy for ischemic disease.