平滑肌细胞表型转变与微区力学研究

Cardiovascular disease is the most common cause of death worldwide. Phenotype switch of vascular smooth muscle cells (VSMCs) contribut-.es to the pathogenesis of several vascular disorders. However the triggers which affect the homeostasis of VSMCs and modulate the phenoty-pe from synthetic to contractile VSMCs are less known. In order to clarify the role of nanoscale mechanics in VSMCs phenotype switch, gold nanoparticles (Au NPs) will be applied as a mechanical tool for exerting force on the microdomain of cell-membrane and the on-off state observation of mechanosensitive channels. Following methods will be included. (1) Employ transmission electron microscope and confocal laser scanning microscope to investigate the intracellular localization of Au NPs in VSMCs; Apply western blot to determine the effects of Au NPs on VSMCs phenotype switch. Utilize scanning electron microscope and atomic force microscope to study the influence of Au NPs on cell membrane and cell elastic modulus. (2) Research on the role of mechanosensitive channels especially TRPM7 during the VSMCs phenotype modulation by ion channel blockers and RNA interference (RNAi) to TRPM7 knockdown. The studies on the relationship between VSMCs phenotype switch and nanoscale mechanics will provide new insight into the control of VSMC phenotype, better understanding of VSMC biology and improved blood vessel substitutes, as well as new treatments for vascular disease.

心血管疾病严重威胁着人类健康，而平滑肌细胞由收缩型向合成型转变是多种血管疾病共同病理过程，但针对平滑肌细胞收缩表型维持以及合成型转变为收缩型的研究报道很少。本项目拟利用细胞膜表面定位的金纳米颗粒作为局部微区力学刺激工具，观察平滑肌细胞膜机械敏感钙通道随局部张力改变的不同开关状态，以阐明合成型向收缩型转变微区力学因素的作用。具体研究包括：（1）利用透射电镜、激光共聚焦显微镜研究金纳米颗粒与细胞的作用方式，利用扫描电镜和原子力显微镜分别检测金纳米颗粒对细胞膜和细胞弹性模量影响，并采用Western印记法鉴定平滑肌细胞表型；（2）利用离子通道阻断剂和RNA干扰技术等探索机械敏感离子通道参与机制，特别是TRPM7的作用。将金纳米颗粒作用于合成型平滑肌细胞，研究平滑肌细胞表型转变与微区力学刺激的关系，为平滑肌细胞的基础研究、血管组织工程和血管疾病的治疗提供一种新的思路和新方法。