Mao Xinjian, Chen Zhe, Luo Qing, Zhang Bingyu, Song Guanbin
Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China.
Cytotechnology. 2016 Dec;68(6):2235-2243. doi: 10.1007/s10616-016-0007-x. Epub 2016 Oct 15.
Exposure to microgravity during space flight affects almost all human physiological systems. Migration, proliferation, and differentiation of stem cells are crucial for tissues repair and regeneration. However, the effect of microgravity on the migration potentials of bone marrow mesenchymal stem cells (BMSCs) is unclear, which are important progenitor and supporting cells. Here, we utilized a clinostat to model simulated microgravity (SMG) and found that SMG obviously inhibited migration of rat BMSCs. We detected significant reorganization of F-actin filaments and increased Young's modulus of BMSCs after exposure to SMG. Moreover, Y-27632 (a specific inhibitor of ROCK) abrogated the inhibited migration capacity and polymerized F-actin filament of BMSCs under SMG. Interestingly, we found that transferring BMSCs to normal gravity also attenuated the polymerized F-actin filament and Young's modulus of BMSCs induced by SMG, but could not recover migration capacity of BMSCs inhibited by SMG. Taken together, we propose that SMG inhibits migration of BMSCs through remodeling F-actin and increasing cell stiffness.
太空飞行期间暴露于微重力环境会影响几乎所有人类生理系统。干细胞的迁移、增殖和分化对于组织修复和再生至关重要。然而,微重力对骨髓间充质干细胞(BMSCs)迁移潜能的影响尚不清楚,而骨髓间充质干细胞是重要的祖细胞和支持细胞。在此,我们利用回转器模拟微重力(SMG),发现SMG明显抑制大鼠骨髓间充质干细胞的迁移。我们检测到暴露于SMG后,骨髓间充质干细胞的F-肌动蛋白丝发生显著重组,杨氏模量增加。此外,Y-27632(一种ROCK特异性抑制剂)消除了SMG条件下骨髓间充质干细胞受抑制的迁移能力,并使F-肌动蛋白丝聚合。有趣的是,我们发现将骨髓间充质干细胞转移到正常重力环境也会减弱SMG诱导的骨髓间充质干细胞F-肌动蛋白丝聚合和杨氏模量,但无法恢复被SMG抑制的骨髓间充质干细胞的迁移能力。综上所述,我们认为SMG通过重塑F-肌动蛋白和增加细胞硬度来抑制骨髓间充质干细胞的迁移。