新型干细胞iPSCs-MSCs对泡沫细胞胆固醇含量的影响及调节机制研究

Effects and modulating mechanism of iPSCs-MSCs on cholesterol concentration in macrophage foam cell

目的探讨新型干细胞iPSCs-MSCs对巨噬细胞源性泡沫细胞胆固醇含量的影响及可能的调控机制。方法运用泡沫细胞模型,采用transwell的方式将iPSCs-MSCs与THP-1巨噬细胞源性泡沫细胞共培养后,使用试剂盒测定细胞内胆固醇的含量,收集细胞培养液用ELISA法检测TNF-α、IL-6的浓度,Western blot和实时荧光定量PCR检测细胞内ATP结合盒转运子A1(ABCA1)的表达。结果与iPSCs-MSCs共培养后泡沫细胞内胆固醇的含量减少,培养基中TNF-α、IL-6浓度显著降低,ABCA1 m RNA和蛋白水平表达增加(P<0.05),Notch 1 mRNA和蛋白水平表达下降(P<0.05)。结论 iPSCs-MSCs可以下调巨噬细胞源性泡沫细胞内胆固醇的含量,该过程可能与上调ABCA1表达及抑制Notch信号通路而减少炎症因子释放有关,提示iPSCs-MSCs有预防和治疗动脉粥样硬化的前景。

Objective This study is to investigate whether iPSCs-MSCs, mesenchymal stem cells derived from induced pluripotent stem cells influence the content of cholesterol in THP-1 macrophage foam cells and the probable modulating mechanism. Method The foam cell model and transwell model were established. After co-cultures of macrophage foam cell with iPSCs-MSCs, cellular cholesterol content was evaluated by cholesterol assay kit and cytokine levels were measured by an enzyme-linked immunosorbent assay. The expression of ABCA1（ATP-Binding Cassette Transporter A1）and Notch1 were detected by Western blot and Quantitative Real-time PCR. Results After co-cultures with iPSCsMSCs, cholesterol content in foam cell was reduced. Levels of TNF-α and IL-6 were decreased significantly. The expressions of m RNA and protein of ABCA1 were up-regulated（P〈0.05）. The expressions of m RNA and protein of Notch1 were down-regulated（P〈0.05）. Conclusions iPSCs-MSCs were capable of reducing cholesterol content of macrophage foam cell, which was probably related to up-regulation of ABCA1 expression and reduction of inflammation cytokines. Moreover, the function of iPSCs-MSCs that inhibited expression of inflammatory cytokines in foam cells might be associated with the inhibition of the Notch signaling pathway. This prompts iPSCs-MSCs may be applied to the prevention and treatment of atherosclerosis.