类风湿性关节炎(RA)是以滑膜炎性增生、血管新生、血管翳形成并侵蚀关节软骨和骨为病理特征的自身免疫性疾病。滑膜微环境主要参与者成纤维滑膜细胞(FLS)和血管内皮细胞(VEC)功能改变与其密切相关；鞘氨醇激酶(SphKs)激活的1-磷酸鞘氨醇(S1P)结合受体S1PR参与细胞增殖、炎症反应，在RA病程中发挥重要作用。但调控炎症机制的信号通路尚不明确。课题组研究发现栀子苷(GE)下调FLS中p-Erk、p-SphK1和S1PR1异常高表达。提出假说：GE双靶调控SphK1和Erk过度磷酸化，调节SphK1-S1P-S1PR1及Ras-Erk信号转导，抑制FLS异常增殖和血管新生，干预炎症反应及VEC功能改变。拟采用基因过表达和沉默、突变质粒构建和转染、细胞共培养等关键技术，探究RA炎症机制，揭示GE双靶调控具体靶点，阐释中医药从“络”治痹理论的科学内涵，为构建治疗RA新的药物作用靶点奠定基础。

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial hyperplasia, angiogenesis, formation of pannus and erosion of articular cartilage and bone. It belongs to the category of “arthralgia” in traditional medicine. The imbalance of synovial microenvironment plays an important role in the development and progression of RA. Fibroblast synovial cells (FLS) and vascular endothelial cells (VEC) are the main participants in synovial microenvironment. The functional changes of FLS and VEC are closely related to the entire course of RA. Sphingosine-1-phosphate (S1P) is a product of activation of sphingosine kinases (SphKs), which is a kind of lysophospholipid with a wide range of biological activities. After its binding with its receptor S1PRs which belong to G protein-coupled receptors (GPCRs), it participates in cell proliferation, apoptosis and infiltration of inflammatory factors through a variety of pathways and plays an important role in autoimmune diseases. But so far, the signaling pathways that regulate the inflammatory mechanisms of RA are not well understood. Our previous studies found that geniposide (GE), an iridoid glycoside obtained from Gardenia jasminoides Ellis, had significant anti-inflammatory effects and inhibitory effects on FLS abnormal proliferation in rats with adjuvant arthritis (AA), and down-regulated the abnormal expression of p-Erk1/2, p-SphK1 and S1PR1 proteins in FLS of AA rats. Based on a good previous experimental foundation and a large number of literature research, we propose the following scientific hypothesis: “GE dual-target regulates the over-phosphorylation of SphK1 and Erk1/2, regulates SphK1-S1P-S1PR1 and downstream GPCRs mediated Ras-MEK1/2-Erk1/2 signal transduction, inhibits abnormal proliferation and angiogenesis of FLS, interfers FLS and VEC inflammatory response and VEC biological function changes, which plays an important role in the treatment of RA”. This topic intends to use the activation and inhibition of signal transduction, gene overexpression and gene silencing, construction and transfection of mutant plasmids, co-immunoprecipitation, immunofluorescence, flow cytometry, ultra performance liquid chromatography-mass spectrometry, RT-qPCR, Western blotting and cell co-culture, and other key technologies to explore the inflammatory pathological mechanism of RA in a deeper level, to reveal the specific target of GE double target regulation and to explain the scientific connotation of Traditional Chinese Medicine from "collaterals" to treat arthralgia, and to lay the foundation for the construction of a new drug target for the treatment of RA.