Department of Urology, Zhongshan Hospital, Shanghai, China.
Department of Urology, Zhongshan Hospital Xuhui Branch, Shanghai, China.
Neurourol Urodyn. 2019 Aug;38(6):1504-1516. doi: 10.1002/nau.24003. Epub 2019 Apr 29.
The present study was designed to study changes and its potential mechanisms in human bladder smooth muscle subjected to stretch.
Bioinformatics analyses including differential expression analysis, overrepresentation enrichment analysis, principal component analysis, and weighted gene coexpression network analysis were used to analyze a microarray dataset (GSE47080) of partial bladder outlet obstruction (pBOO) in rat to find the potential changes of gene expressions. Bladder from pBOO model and human bladder smooth muscle cells (HBSMCs) subjected to sustained prolonged stretch were collected for Western blot analysis, real-time polymerase chain reaction, and fluorescence analysis to verify the changes of gene expressions and preliminarily study the potential role of signaling pathway regulation in treatment of pBOO.
The bioinformatics analysis showed that chronic obstruction activated mitogen-activated protein kinase pathway and changed cytoskeleton structure in bladder smooth muscle. In in vivo experiments in mice, pBOO was verified by cystometry. Partial BOO activated the extracellular signal-regulated kinase (ERK)/p90 ribosomal S6 protein kinase (p90RSK)/nuclear factor-κB (NF-κB) signaling pathway in DM. The messenger RNA (mRNA) expressions of contractile phenotypic proteins increased after pBOO. In in vitro experiments of HBSMCs, mechanical stretch activated ERK/p90RSK/NF-κB in HBSMCs in a time-dependent manner. The mRNA expressions of α-smooth muscle actin and SM22 also increased and filamentous actin (F-actin) polymerization was enhanced as well. Inhibition of ERK/p90RSK/NF-κB pathway reversed mechanical stretch-induced changes of contractile phenotypic expression and F-action polymerization.
Continuous stretch increases expressions of contractile phenotypic proteins and promotes the polymerization of F-actin. This process partially goes through ERK/p90RSK/NF-κB pathway.
本研究旨在研究人膀胱平滑肌在拉伸下的变化及其潜在机制。
采用生物信息学分析方法，包括差异表达分析、过表达富集分析、主成分分析和加权基因共表达网络分析，对大鼠部分膀胱出口梗阻（pBOO）的微阵列数据集（GSE47080）进行分析，以寻找基因表达变化的潜在变化。收集 pBOO 模型和人膀胱平滑肌细胞（HBSMCs）持续长时间拉伸后的膀胱组织，进行 Western blot 分析、实时聚合酶链反应和荧光分析，以验证基因表达的变化，并初步研究信号通路调节在 pBOO 治疗中的潜在作用。
生物信息学分析表明，慢性梗阻激活丝裂原活化蛋白激酶途径并改变膀胱平滑肌的细胞骨架结构。在小鼠体内实验中，通过膀胱测压验证了 pBOO。部分 BOO 在 DM 中激活细胞外信号调节激酶（ERK）/p90 核糖体 S6 蛋白激酶（p90RSK）/核因子-κB（NF-κB）信号通路。pBOO 后收缩表型蛋白的信使 RNA（mRNA）表达增加。在 HBSMCs 的体外实验中，机械拉伸以时间依赖性方式激活 HBSMCs 中的 ERK/p90RSK/NF-κB。α-平滑肌肌动蛋白和 SM22 的 mRNA 表达也增加，丝状肌动蛋白（F-肌动蛋白）聚合增强。ERK/p90RSK/NF-κB 通路的抑制逆转了机械拉伸诱导的收缩表型表达和 F-肌动蛋白聚合的变化。
持续拉伸会增加收缩表型蛋白的表达，并促进 F-肌动蛋白的聚合。这个过程部分通过 ERK/p90RSK/NF-κB 通路进行。
