Smooth muscle cells differentiated from mesenchymal stem cells are regulated by microRNAs and suitable for vascular tissue grafts.
Smooth muscle cells differentiated from mesenchymal stem cells are regulated by microRNAs and suitable for vascular tissue grafts.
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DOI：
10.1074/jbc.ra118.001739
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发表时间：
2018-05-25
期刊：
影响因子：
--
通讯作者：
Xu Q
中科院分区：
文献类型：
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作者：
Gu W;Hong X;Le Bras A;Nowak WN;Issa Bhaloo S;Deng J;Xie Y;Hu Y;Ruan XZ;Xu Q
具有长期通畅的组织工程血管移植在临床中是非常需要的，而平滑肌细胞（SMCs）是一个关键的移植物成分。人间充质干细胞（MSCs）用于生成SMCs，了解MSCs向SMC分化过程的潜在调控机制可以改善临床SMC的生成。本研究发现，在转化生长因子-β1 （tgf -β1）的刺激下，人脐带源性间充质干细胞在基因和蛋白水平上大量表达SMC标志物α-平滑肌肌动蛋白（αSMA）、平滑肌蛋白22 （SM22）、钙钙蛋白和平滑肌肌球蛋白重链（SMMHC）。在功能上，msc衍生的SMCs在体外表现出收缩能力，并在体内支持血管结构的形成。更重要的是，从人间充质干细胞分化的SMCs可以迁移到去细胞化的小鼠主动脉中，并产生血管移植物的平滑肌层，这表明利用人间充质干细胞衍生的SMCs产生血管移植物的潜力。值得注意的是，microRNA （miR）阵列分析和TaqMan microRNA测定发现，miR-503和miR-222-5p在早期时间点是MSC向SMCs分化的潜在调节因子。在机制上，miR-503通过直接靶向SMAD7促进SMC分化，SMAD7是smad相关的tgf β1介导的信号通路的抑制因子。此外，miR-503的表达依赖于smad4。SMAD4在miR-503启动子处富集。此外，miR-222-5p通过靶向和下调ROCK2和αSMA抑制SMC分化。总之，MSC向SMCs的分化受miR-503和miR-222-5p的调控，并产生用于血管移植物的功能性SMCs。
Tissue-engineered vascular grafts with long-term patency are greatly needed in the clinical settings, and smooth muscle cells (SMCs) are a critical graft component. Human mesenchymal stem cells (MSCs) are used for generating SMCs, and understanding the underlying regulatory mechanisms of the MSC-to-SMC differentiation process could improve SMC generation in the clinic. Here, we found that in response to stimulation of transforming growth factor-β1 (TGFβ1), human umbilical cord–derived MSCs abundantly express the SMC markers α-smooth muscle actin (αSMA), smooth muscle protein 22 (SM22), calponin, and smooth muscle myosin heavy chain (SMMHC) at both gene and protein levels. Functionally, MSC-derived SMCs displayed contracting capacity in vitro and supported vascular structure formation in the Matrigel plug assay in vivo. More importantly, SMCs differentiated from human MSCs could migrate into decellularized mouse aorta and give rise to the smooth muscle layer of vascular grafts, indicating the potential of utilizing human MSC-derived SMCs to generate vascular grafts. Of note, microRNA (miR) array analysis and TaqMan microRNA assays identified miR-503 and miR-222-5p as potential regulators of MSC differentiation into SMCs at early time points. Mechanistically, miR-503 promoted SMC differentiation by directly targeting SMAD7, a suppressor of SMAD-related, TGFβ1-mediated signaling pathways. Moreover, miR-503 expression was SMAD4-dependent. SMAD4 was enriched at the miR-503 promoter. Furthermore, miR-222-5p inhibited SMC differentiation by targeting and down-regulating ROCK2 and αSMA. In conclusion, MSC differentiation into SMCs is regulated by miR-503 and miR-222-5p and yields functional SMCs for use in vascular grafts.