转录共激活因子在金雀异黄酮促进小鼠骨髓间充质干细胞向成骨细胞分化过程中的作用  

Role of TAZ in genistein induced osteoblastogenic differentiation of mouse bone marrow-derived mesenchymal stem cells

作　　者：廖清船[1] 刘霆[2] 任平[1] 张又枝[1] 余薇[3] 蔡飞[3] 闵清[1] 刘超[3] 

机构地区：[1]湖北科技学院药学院,437100 [2] 中南大学湘雅医院消化科 [3] 湖北科技学院糖尿病与心脑血管病变实验室

出　　处：《中华内分泌代谢杂志》2016年第2期133-138,共6页Chinese Journal of Endocrinology and Metabolism

基　　金：湖北省教育厅科学技术研究项目（B2014018）

摘　　要：目的：研究转录共激活因子（TAZ）在金雀异黄酮（Gen）促进小鼠骨髓间充质干细胞（ BMSCs）向成骨细胞分化过程中的作用。方法全骨髓贴壁法原代培养小鼠BMSCs，测定碱性磷酸酶（ ALP）活性、钙（ Ca）沉积量、骨唾液酸蛋白（ BSP）和骨钙素（ OC）表达水平反映BMSCs向成骨细胞分化状况；设计并合成针对TAZ的siRNA（ siTAZ）转染BMSCs，在成骨定向分化培养基中添加Gen，比较siTAZ转染组与siTAZ未转染组成骨细胞分化状况；免疫共沉淀实验观察TAZ和成骨细胞特异性转录因子cbfa1的结合，并观察Gen对TAZ表达及其与cbfa1结合的影响。结果 BMSCs向成骨细胞诱导分化过程检测到TAZ表达，siTAZ 转染后 ALP 活性、Ca 沉积量显著降低。 Gen 剂量依赖性（0．01μmol／L、0．1μmol／L、1μmol／L）刺激TAZ蛋白表达增加；Gen（1μmol／L）不仅增加TAZ总蛋白表达，还促使TAZ向细胞核内移位，Gen（1μmol／L）显著提高培养细胞ALP活性、Ca沉积量以及BSP和OC表达水平，而在siTAZ转染组则未见明显变化；免疫共沉淀证实TAZ可以直接与cbfa1结合，Gen（1μmol／L）可使TAZ与cbfa1结合增强。结论 TAZ参与了BMSCs向成骨细胞分化过程，Gen可通过增强TAZ表达及核移位促进BMSCs向成骨细胞分化。Objective To investigate the role of transcriptional-coactivator with PDZ-binding motif（ TAZ） in genistein-induced osteoblastogenic differentiation of mouse bone marrow-derived mesenchymal stem cells （ BMSCs） .Methods Mouse BMSCs were cultured in phenol red-freeα-MEM containing osteogenic supplements for inducing osteogenic differentiation.BMSCs were transfected with siRNA-TAZ and treated with genistein.The temporal sequence of osteoblastic differentiation in BMSCs cultures was assayed by measuring alkaline phosphatase activity （ALP） and calcium deposition.The mRNA expression of bone sialoprotein （ BSP） and osteocalcin （ OC） were detected by reverse transcription-polymerase chain reaction（RT-PCR）.The binding interaction between TAZ and cbfa1 was identified by co-immunoprecipitation.Results TAZ expression was detected during the induction of osteogenic differentiation, the ALP activity and calcium deposition were significantly decreased in BMSCs which were transfected with siRNA-TAZ.Genistein（0.01-1 μmol/L） exhibited a dose-dependent effect on TAZ expression in mouse BMSCs cultures.Treatment with genistein （ 1 μmol/L ） resulted in increased ALP avtivity and calcium deposition of BMSC cultures as function of time.Genistein（1μmol/L） also promoted the nuclear localization of TAZ and augmented the interaction between TAZ and cbfa1, and by which upregulated cbfa1-mediated gene expression such as BSP and OC.However, the ALP avtivity and calcium deposition, as well as the expression of BSP and OC were not promoted by genistein in BMSCs transfected with siRNA-TAZ.Conclusion These data suggest that the TAZ plays an important role in genistein-induced osteoblastic differentiation of mouse BMSCs cultures.

关 键 词：金雀异黄酮 骨髓间充质干细胞 成骨细胞分化 转录共激活因子 

分 类 号：R580[医药卫生—内分泌]