Optimization of S1P3 antagonists for fibrotic disease

 描述(申请人提供)：本申请是对PAR-14-279“体内化学探针(R01)的发现”的响应，针对关节炎、肌肉骨骼和皮肤疾病。我们建议验证S1PR3作为治疗关节炎和纤维化的机制靶点。A类GPCR超家族在药物发现方面具有很高的生产力。1-磷酸鞘氨醇受体家族由5个GPCRs组成，即S1PR1、S1PR2、S1PR3、S1PR4和S1P5，调节多种生物学反应，包括淋巴细胞转运、血管紧张性、细胞分化和生存。文献和我们的初步数据支持S1P在炎症和纤维化中的作用。S1PR3激动剂在包括灵长类在内的多种物种中具有剂量限制性毒性，具有纤维化作用。此外，S1PR3促进细胞因子的产生，以响应内毒素，S1PR3的缺失或化学拮抗都会钝化细胞因子的放大并抑制纤维化。类风湿关节炎成纤维细胞样滑膜细胞(RA-FLS)的增殖、迁移、分泌细胞外基质和炎性细胞因子被认为是疾病进展的中心，并依赖于肿瘤坏死因子和S1P。S1PR3在RA-FLS中的表达升高。在肿瘤坏死因子-α诱导的关节炎小鼠中，鞘氨醇激酶1的基因缺失减少了包括滑膜炎症和关节侵蚀在内的症状。类风湿关节炎患者滑液中S1P也升高。我们建议通过寻找有效的、选择性的、生物可用的S1PR3受体拮抗剂并在体外和体内进行概念验证来验证S1PR3作为治疗靶点的有效性。这些目标将通过两个具体目标来实现：目标1：开发和优化具有更高效力、选择性和药代动力学特性的S1PR3选择性配体。目前的S1P受体配体将针对S1PR3与其他S1P受体家族成员S1P1、S1P2、S1P4和S1P5的效力和功能选择性进行优化。S1PR3选择性拮抗剂化合物的物理化学性质，包括微生物体的稳定性、溶解性、总极性表面积和药代动力学性质(联合分布)将被优化，以便在体内使用。目的2：研究S1PR3拮抗剂的体内外药理和功能特性。该项目将提供新的选择性、高效和生物可用的探针，专门调节S1PR3信号。这些化合物将有助于验证S1PR3作为治疗类风湿性关节炎的药物靶点。我们将在体外测试化合物抑制细胞增殖、迁移和细胞因子分泌的能力，并在体内测试化合物在TNFdeltaARE模型中减轻RA症状和预后的能力。

 DESCRIPTION (provided by applicant): This application is in response to PAR-14-279 "Discovery of in vivo Chemical Probes (R01)" and targets arthritis, musculoskeletal and skin diseases. We propose to validate S1PR3 as a mechanistic target for arthritis and fibrosis. The class A GPCR superfamily is highly productive for drug discovery. The sphingosine- 1-phosphate receptor family consists of 5 GPCRs, S1PR1, S1PR2, S1PR3, S1PR4 and S1P5 and regulates multiple biological responses including lymphocyte trafficking, vascular tone, cell differentiation and survival. The literature and our preliminary data support a role for S1P in inflammation and fibrosis. Agonists of S1PR3 have fibrosis as the dose-limiting toxicity across multiple species including primates. Also, S1PR3 enhances cytokine production in response to LPS, and both deletion of S1PR3 or chemical antagonism blunts cytokine amplification and inhibits fibrosis. The proliferation, migration, secretion of extra-cellular matrix and inflammator cytokines by Rheumatoid arthritis fibroblast-like-synoviocytes (RA-FLS) are thought to be central in disease progression and are dependent on both TNF and S1P. S1PR3 expression is elevated in RA-FLS. Genetic deletion of Sphingosine kinase 1 in the TNF-α-induced arthritis mouse reduced symptoms including synovial inflammation and joint erosion. S1P is also elevated in the synovial fluid of RA patients. We propose to validate S1PR3 as a therapeutic target by identifying potent, selective, bioavailable antagonists of the S1PR3 receptor and demonstrating proof-of-concept in vitro and in vivo. These goals will be approached through two Specific Aims: Aim 1: Develop and optimize S1PR3-selective ligands with improved potency, selectivity and pharmacokinetic properties. Current S1P receptor ligands will be optimized for potency and functional selectivity for S1PR3 versus other S1P receptor family members; S1P1, S1P2, S1P4 and S1P5. Physicochemical properties of S1PR3 selective antagonist compounds including microsome stability, solubility, total polar surface area and pharmacokinetics properties (joint distribution) will be optimized for in vivo use. Aim 2: Pharmacological and functional characterization of S1PR3 antagonists in vitro and in vivo. This project will deliver new selective potent and bioavailable probes that specifically modulate S1PR3 signaling. Such compounds will facilitate validation of S1PR3 as a drug target for rheumatoid arthritis. We will test compounds in vitro for their ability to inhibit cell proliferation, migration and cytokine secretion and in vivo to reduce RA symptoms and outcomes in TNFdeltaARE model.