This study aimed to evaluate the effect of sanguinarine on biomechanical properties of rat airway smooth muscle cells (rASMCs) including stiffness, traction force and cytoskeletal stress fiber organization. To do so, rASMCs cultured in vitro were treated with sanguinarine solution at different concentrations (0.005~5 μmol/L) for 12 h, 24 h, 36 h, and 48 h, respectively. Subsequently, the cells were tested for their viability, stiffness, traction force, migration and microfilament distribution by using methylthiazolyldiphenyl-tetrazolium bromide assay, optical magnetic twisting cytometry, Fourier transform traction microscopy, scratch wound healing method, and immunofluorescence microscopy, respectively. The results showed that at concentration below 0.5 μmol/L sanguinarine had no effect on cell viability, but caused dose and time dependent effect on cell biomechanics. Specifically, rASMCs treated with sanguinarine at 0.05 μmol/L and 0.5 μmol/L for 12 and 24 h exhibited significant reduction in stiffness, traction force and migration speed, together with disorganization of the cytoskeletal stress fibers. Considering the essential role of airway smooth muscle cells (ASMCs) biomechanics in the airway hyperresponsiveness (AHR) of asthma, these findings suggest that sanguinarine may ameliorate AHR via alteration of ASMCs biomechanical properties, thus providing a novel approach for asthma drug development.
本研究拟探究血根碱对大鼠气道平滑肌细胞（rASMCs）的刚度、牵张力、应力纤维分布等细胞生物力学特性的影响。体外培养的 rASMCs 经过血根碱溶液在不同浓度（0.005～5 μmol/L）条件下分别处理 12 h、24 h、36 h 和 48 h 后，采用噻唑盐比色法、光学磁粒扭转细胞测量仪、傅里叶变换牵张力显微术、划痕实验和免疫荧光显微技术等检测其活性、刚度、牵张力、迁移速度和微丝骨架分布等细胞生物力学特性的变化。实验结果显示，在浓度低于 0.5 μmol/L 时，血根碱对细胞活性没有明显影响，但对细胞生物力学特性呈现浓度和时间依赖性，具体表现为 rAMSCs 经 0.05 μmol/L 和 0.5 μmol/L 浓度的血根碱处理 12 h 和 24 h 后细胞刚度、细胞牵张力和细胞迁移速度均明显降低、细胞骨架应力纤维出现解聚。鉴于气道平滑肌细胞（ASMCs）生物力学特性在哮喘气道高反应性（AHR）中的关键作用，上述的实验结果提示，血根碱有可能通过改变气道平滑肌细胞生物力学特性而改善 AHR，进而为开发基于血根碱的气道松弛剂等哮喘治疗药物奠定基础。.
Keywords: airway smooth muscle cells; biomechanics; cell stiffness; cell traction force; sanguinarine.