ABSTRACT
As a new type of immunosuppressant，iguratimod can mediate the anti-inflammatory signaling pathway by inhibiting the proliferation of inflammatory cells and reducing the release of inflammatory cytokines， and play the role of anti-inflammatory. It can affect the proliferation of immune cells and the expression of immune factors，reduce the production and deposition of immune complexes in the body，and play the role of immune regulation. It can regulate bone metabolism by mediating signaling pathways such as Wnt/β-catenin，Toll-like receptor 4/nuclear factor-κB and osteoprotegerin/nuclear factor-κB receptor activating factor ligand， and play a role in bone protection. It can inhibit pulmonary fibrosis by inhibiting the expression of transforming growth factor β1/ Smad2/3 signaling pathway，tumor necrosis factor-α，interleukin-1，interleukin-6，matrix metalloproteinase-9 and other inflammatory cytokines in lung tissue，and inhibiting the expression of collagen and fibronectin. Its efficacy and safety have been confirmed in the clinical application of rheumatoid arthritis and primary Sjogren syndrome and included in the diagnosis and treatment of the disease. It has also shown good efficacy in the clinical application of other connective tissue diseases such as systemic lupus erythematosus and ankylosing spondylitis，and no obvious safety risks have been found.
