Urology Research Laboratory, Department of Clinical Research, University of Bern, Bern, Switzerland.
J Urol. 2013 Jul;190(1):325-33. doi: 10.1016/j.juro.2013.01.088. Epub 2013 Jan 31.
We examined the role of annexins in bladder urothelium. We characterized expression and distribution in normal bladders, biopsies from patients with bladder pain syndrome, cultured human urothelium and urothelial TEU-2 cells.
Annexin expression in bladder layers was analyzed by quantitative reverse transcriptase-polymerase chain reaction and immunofluorescence. We assessed cell survival after exposure to the pore forming bacterial toxin streptolysin O by microscopy and alamarBlue® assay. Bladder dome biopsies were obtained from 8 asymptomatic controls and 28 patients with symptoms of bladder pain syndrome.
Annexin A1, A2, A5 and A6 were differentially distributed in bladder layers. Annexin A6 was abundant in detrusor smooth muscle and low in urothelium, while annexin A1 was the highest in urothelium. Annexin A2 was localized to the lateral membrane of umbrella cells but excluded from tight junctions. TEU-2 cell differentiation caused up-regulation of annexin A1 and A2 and down-regulation of annexin A6 mRNA. Mature urothelium dedifferentiation during culture caused the opposite effect, decreasing annexin A1 and increasing annexin A6. Annexin A2 influenced TEU-2 cell epithelial permeability. siRNA mediated knockdown of annexin A1 in TEU-2 cells caused significantly decreased cell survival after streptolysin O exposure. Annexin A1 was significantly reduced in biopsies from patients with bladder pain syndrome.
Several annexins are expressed in human bladder and TEU-2 cells, in which levels are regulated during urothelial differentiation. Annexin A1 down-regulation in patients with bladder pain syndrome might decrease cell survival and contribute to compromised urothelial function.
研究膜联蛋白在膀胱尿路上皮中的作用。我们对正常膀胱、膀胱疼痛综合征患者活检组织、培养的人尿路上皮和尿路上皮 TEU-2 细胞进行了特征描述和表达分布分析。
采用定量逆转录聚合酶链反应和免疫荧光技术分析膀胱各层的膜联蛋白表达情况。通过显微镜和 alamarBlue®检测评估细胞在孔形成细菌毒素链球菌溶血素 O 暴露后的存活率。从 8 名无症状对照者和 28 名膀胱疼痛综合征患者中获取膀胱穹窿活检组织。
膜联蛋白 A1、A2、A5 和 A6 在膀胱各层中呈差异分布。膜联蛋白 A6 在逼尿肌平滑肌中丰富，而在尿路上皮中含量较低，而膜联蛋白 A1 在尿路上皮中含量最高。膜联蛋白 A2 定位于伞细胞的侧膜，但不位于紧密连接。TEU-2 细胞分化导致膜联蛋白 A1 和 A2 的 mRNA 上调和 A6 的下调。培养过程中成熟尿路上皮去分化导致相反的效果，降低膜联蛋白 A1 并增加膜联蛋白 A6。膜联蛋白 A2 影响 TEU-2 细胞的上皮通透性。siRNA 介导的膜联蛋白 A1 在 TEU-2 细胞中的敲低导致链球菌溶血素 O 暴露后细胞存活率显著降低。膀胱疼痛综合征患者的活检组织中膜联蛋白 A1 明显减少。
几种膜联蛋白在人膀胱和 TEU-2 细胞中表达，其在尿路上皮分化过程中受到调节。膀胱疼痛综合征患者中膜联蛋白 A1 的下调可能降低细胞存活率并导致尿路上皮功能受损。
