Qiu Yiyan, Chen Yang, Zeng Tenghui, Guo Weizhuang, Zhou Wenyu, Yang Xinjian
Department of Spine Surgery, The 2nd Shenzhen People's Hospital, No. 3002, Sungang Road, Futian District, Shenzhen, 510000, China.
Mol Biol Rep. 2016 Mar;43(3):183-93. doi: 10.1007/s11033-015-3936-0. Epub 2016 Jan 16.
The healing process of fractured bone is affected by the multiple factors regulating the growth and differentiation of osteoblasts and bone mesenchymal stem cells (MSCs), however, such markers and molecular events need to be orchestrated in details. This study investigated the effect of polyphenol(-)-epigallocatechin-3-gallate (EGCG) on the hypoxia-induced apoptosis and osteogenic differentiation of human bone marrow-derived MSCs, examined the miR-210 induction by EGCG, explored the target inhibition of the expression of receptor tyrosine kinase ligand ephrin-A3 (EFNA3) by miR-210, and then determined the association of the miR-210 promotion with the hypoxia-induced apoptosis and osteogenic differentiation. Results demonstrated that EGCG treatment significantly inhibited the hypoxia-induced apoptosis in MSCs and promoted the level of alkaline phosphatase (ALP), bone morphogenetic protein 2 (BMP-2), propeptide of type I procollagen I (PINP) and runt-related transcription factor 2 (RUNX2) in MSCs under either normoxia or hypoxia. Moreover, the EGCG treatment upregulated the miR-210 expression, in an association with EFNA3 downregulation; and the miR-210 upregulation significantly downregulated the expression of EFNA3 via the specific binding to the 3' UTR of EFNA3. In addition, the manipulated miR-210 upregulation exerted amelioration on the hypoxia-induced apoptosis and on the hypoxia-reduced expression of ALP, BMP-2, PINP and RUNX2 in MSCs. In summary, our study indicated the protective role of EGCG in response to hypoxia and promontory role to osteogenic differentiation in MSCs via upregulating miR-210 and downregulating the expression of miR-210-targeted EFNA3. Our study implies the protective role of EGCG in the hypoxia-induced impairment in MSCs.
骨折的愈合过程受到多种调节成骨细胞和骨髓间充质干细胞（MSCs）生长与分化的因素影响，然而，这些标志物和分子事件需要进行详细的协调。本研究调查了多酚（-）-表没食子儿茶素-3-没食子酸酯（EGCG）对缺氧诱导的人骨髓来源MSCs凋亡和成骨分化的影响，检测了EGCG诱导的miR-210，探索了miR-210对受体酪氨酸激酶配体 Ephrin-A3（EFNA3）表达的靶向抑制作用，然后确定了miR-210上调与缺氧诱导的凋亡和成骨分化之间的关联。结果表明，EGCG处理显著抑制了缺氧诱导的MSCs凋亡，并在常氧或缺氧条件下促进了MSCs中碱性磷酸酶（ALP）、骨形态发生蛋白2（BMP-2）、I型前胶原I原肽（PINP）和 runt相关转录因子2（RUNX2）的水平。此外，EGCG处理上调了miR-210表达，与EFNA3下调相关；miR-210上调通过与EFNA3的3'UTR特异性结合显著下调了EFNA3的表达。此外，操纵性miR-210上调对缺氧诱导的凋亡以及缺氧降低的MSCs中ALP、BMP-2、PINP和RUNX2表达具有改善作用。总之，我们的研究表明EGCG通过上调miR-210和下调miR-210靶向的EFNA3表达，在应对缺氧时对MSCs具有保护作用，并对其成骨分化具有促进作用。我们的研究暗示了EGCG在缺氧诱导的MSCs损伤中的保护作用。
