IGFBP7促进人脐带间充质干细胞的软骨分化

IGFBP7 promotes human umbilical cord-derived mesenchymal stem cells to differentiate into chondrocytes

目的:探究胰岛素样生长因子结合蛋白7(insulin-like growth factor-binding protein 7,IGFBP7)对人脐带间充质干细胞(human umbilical cord-derived mesenchymal stem cells,hUC-MSCs)软骨分化的影响。方法:用软骨诱导培养基高密度成球培养hUC-MSCs,诱导成软骨分化,通过real-time PCR和Western blot检测软骨分化标志基因Sox9的表达,甲苯胺蓝染色检测蛋白聚糖的表达,以反映细胞外基质沉积情况;real-time PCR和Western blot检测IGFBP7在hUC-MSCs软骨分化过程中的表达情况;在hUC-MSCs中分别瞬时转染IGFBP7的表达质粒和siRNA以改变内源性IGFBP7表达水平,然后成软骨诱导,采用甲苯胺蓝染色,real-time PCR和Western blot检测IGFBP7表达变化对于hUC-MSCs成软骨分化的影响。结果:在hUC-MSCs成软骨分化过程中,IGFBP7 mRNA水平和蛋白水平表达均显著升高。与对照组相比,过表达IGFBP7的hUC-MSCs经成软骨诱导后,Sox9表达量显著升高,甲苯胺蓝染色更深,软骨分化能力更强。反之,敲低IGFBP7表达后,hUC-MSCs的软骨分化能力降低。结论:IGFBP7促进人脐带间充质干细胞成软骨分化。

Objective:This study aims to investigate the role and function of insulin-like growth factor-binding protein 7(IGFBP7 in the chondrogenic differentiation of human umbilical cord-derived mesenchymal stem cells(hUC-MSCs).Methods:Human umbilical cord-derived mesenchymal stem cells(hUC-MSCs)were cultured in high-density pellets to establish a chondrogenic differentiation model.Differences in cartilage differentiation were detected by alcian blue staining.hUC-MSCs was transfected with pCMV3-IGFBP7 or si-IGFBP7 to change the expression level of IGFBP7.The expression level of IGFBP7 was detected in chondrogenesis by real-time PCR and Western blot.The chondrogenesis-related marker gene Sox9 was determined by real-time PCR and Western blot.Results:IGFBP7 mRNA and protein expression significantly increased after induction of chondrogenic differentiation.The level of IGFBP7 in hUC-MSCs transfected with pCMV3-IGFBP7 was significantly increased,while the level of IGFBP7 in the si-IGFBP7 group was significantly reduced.Over-expression of IGFBP7 increased mRNA and protein level of Sox9 and promoted the differentiation of hUC-MSCs into chondrocyte.On the contrary,suppression of IGFBP7 inhibited chondrogenic differentiation.Conclusion:IGFBP7 was a positive regulator in the chondrogenic differentiation of h UC-MSCs.