Department of Urology, Institute of Urology (Laboratory of Reconstructive Urology), West China Hospital, Sichuan University, No. 37 Guo Xue Xiang, Chengdu, 610041, Sichuan, People's Republic of China.
World J Urol. 2017 Aug;35(8):1247-1254. doi: 10.1007/s00345-016-1993-1. Epub 2016 Dec 24.
To investigate the effect of simulated physiological stretch on the expression of extracellular matrix (ECM) proteins and the role of integrin α4/αv, focal adhesion kinase (FAK), extracellular regulated protein kinases 1/2 (ERK1/2) in the stretch-induced ECM protein expression of human bladder smooth muscle cells (HBSMCs).
HBSMCs were seeded onto silicone membrane and subjected to simulated physiological stretch at the range of 5, 10, and 15% elongation. Expression of primary ECM proteins in HBSMCs was analyzed by real-time polymerase chain reaction and Western blot. Specificity of the FAK and ERK1/2 was determined by Western blot with FAK inhibitor and ERK1/2 inhibitor (PD98059). Specificity of integrin α4 and integrin αv was determined with small interfering ribonucleic acid (siRNA) transfection.
The expression of collagen I (Col1), collagen III (Col3), and fibronectin (Fn) was increased significantly under the simulated physiological stretch of 10 and 15%. Integrin α4 and αv, FAK, ERK1/2 were activated by 10% simulated physiological stretch compared with the static condition. Pretreatment of ERK1/2 inhibitor, FAK inhibitor, integrin α4 siRNA, or integrin αv siRNA reduced the stretch-induced expression of ECM proteins. And FAK inhibitor decreased the stretch-induced ERK1/2 activity and ECM protein expression. Integrin α4 siRNA or integrin αv siRNA inhibited the stretch-induced activity of FAK.
Simulated physiological stretch increases the expression of ECM proteins in HBSMCs, and integrin α4/αv-FAK-ERK1/2 signaling pathway partly modulates the mechano-transducing process.
研究模拟生理拉伸对细胞外基质（ECM）蛋白表达的影响，以及整合素 α4/αv、粘着斑激酶（FAK）、细胞外调节蛋白激酶 1/2（ERK1/2）在人膀胱平滑肌细胞（HBSMC）拉伸诱导 ECM 蛋白表达中的作用。
将 HBSMC 接种在硅橡胶膜上，在 5%、10%和 15%伸长率范围内进行模拟生理拉伸。通过实时聚合酶链反应和 Western blot 分析 HBSMC 中主要 ECM 蛋白的表达。用 FAK 抑制剂和 ERK1/2 抑制剂（PD98059）通过 Western blot 确定 FAK 和 ERK1/2 的特异性。用小干扰核糖核酸（siRNA）转染确定整合素 α4 和整合素 αv 的特异性。
在 10%和 15%的模拟生理拉伸下，Col1、Col3 和 Fn 的表达显著增加。与静态条件相比，10%的模拟生理拉伸激活了整合素 α4 和 αv、FAK 和 ERK1/2。ERK1/2 抑制剂、FAK 抑制剂、整合素 α4 siRNA 或整合素 αv siRNA 的预处理降低了拉伸诱导的 ECM 蛋白表达。FAK 抑制剂降低了拉伸诱导的 ERK1/2 活性和 ECM 蛋白表达。整合素 α4 siRNA 或整合素 αv siRNA 抑制了拉伸诱导的 FAK 活性。
模拟生理拉伸增加了 HBSMCs 中 ECM 蛋白的表达，整合素 α4/αv-FAK-ERK1/2 信号通路部分调节了机械转导过程。
