ERβ调控H2S通路在膀胱高敏感及女性间质性膀胱炎/膀胱疼痛综合症发生发展中的作用和机制研究

Female IC/BPS patients manifest with a series of symptoms of hypersensitive bladder. The mechanism of IC/BPS consists of the changes of urothelial sensory function, abnormal autoimmune reaction, inflammatory stimulation and so on. The pathogenesis of female IC/BPS is closely related to the changes of estrogen axis and ERβ pathway plays an important role in the pathogenesis of IC/BPS. Previous study indicated the changes of H2S pathways in urothelial ERβ-specific transgenic mice bladder. The H2S pathways have an influence on a number of physiological processes such as smooth muscle relaxation, pain sensation, inflammation and so on. Besides, The H2S pathways play a role in the urogenital tract. However, H2S pathways have not been systematically studied in IC/BPS. Therefore, we propose that ERβ regulating H2S pathway played an important role in hypersensitive bladder and female IC/BPS. To verify this hypothesis, we intends to use a variety of animal models and clinical IC/BPS patients samples from three aspects. Firstly, the changes of ERβand H2S molecular pathways will be examined in IC/BPS patients and the predictive models will be establish. Next, we intend to explore the regulating effect of ERβto H2S. Last but not the least, the influence of ERβregulating H2S pathway to hypersensitive bladder and female IC/BPS will be further investigate. We would like to provide the theoretical basis and targets for female IC/BPS patients.

女性IC/BPS表现为膀胱敏感性增高的一系列症状，发病机制主要包括尿路上皮感觉功能改变、自身免疫异常及炎症刺激等。女性IC/BPS与雌激素轴的改变密切相关，ERβ通路在IC/BPS的发病中发挥重要作用。前期构建的尿路上皮特异性ERβ转基因小鼠膀胱中H2S通路发生改变。而H2S在平滑肌舒张、疼痛感觉、炎症反应等多个生理过程中发挥作用。H2S可在泌尿生殖道中发挥作用，但在IC/BPS中尚未有系统研究。因此提出ERβ通过调控H2S通路参与膀胱高敏感及女性IC/BPS 的发生与进展这一假设。为验证这一假设，本项目拟采用多种动物模型及临床IC/BPS患者标本，从三个方面开展：①探究IC/BPS患者中ERβ及H2S分子通路变化情况，建立IC/BPS患者预测模型；②探讨ERβ对H2S的调节作用；③探究ERβ调控H2S通路对膀胱敏感性和IC/BPS的影响。为女性IC/BPS的防治提供理论基础及作用靶点。

间质性膀胱炎/膀胱疼痛综合征（IC/BPS）严重影响了患者的生活质量，膀胱疼痛是IC/BPS的主要症状。硫化氢（H2S）现在被认为是继NO和CO之后发现的第三种气体小分子，在生理和病理条件下均发挥重要作用。既往研究发现，胱硫醚β-合酶（CBS）或胱硫醚γ-裂解酶（CSE）生成的H2S可加剧膀胱超敏反应。本课题以膀胱疼痛为重点，通过膀胱内滴注PAR4激活肽构建小鼠膀胱疼痛模型，开展动物实验和细胞学实验，探讨H2S通路在蛋白酶激活受体4（PAR4）诱导的膀胱疼痛中的作用。本课题研究发现，CSE和CBS途径同时存在于小鼠膀胱和SV-HUC-1细胞中。在PAR4诱导的膀胱疼痛模型中，H2S信号被上调，而在人膀胱组织，小鼠膀胱组织和SV-HUC-1细胞中，硫化氢合成酶的活性也被上调。AOAA或NaHS预处理分别抑制或促进PAR4引起的机械性痛觉过敏；但是，PAG仅部分抑制PAR4引起的膀胱疼痛。用PAG或AOAA处理可降低小鼠膀胱和SV-HUC-1细胞中的H2S产生。 AOAA预处理增加了膀胱组织和细胞中MIF的蛋白水平，而NaHS预处理则降低了MIF的蛋白水平。此外，由H2S途径引发的膀胱疼痛并未伴有炎症或排尿行为改变。因此，CBS或CSE产生的内源性H2S可在PAR4诱导的小鼠膀胱疼痛中引起MIF介导的膀胱痛觉过敏，而不会导致膀胱损伤或排尿行为改变。总之，本研究表明H2S通道在IC/BPS发病机制中起到重要作用，可望成为治疗IC/BPS的有效靶点。