7-3--dihydroxy-4--methoxyisoflavone and Arthritis--Rheumatoid

The activation of synovial fibroblasts (SFs) and the subsequent production and expression of pro-inflammatory cytokines play a crucial role in the pathogenesis and progression of rheumatoid arthritis (RA). In the current study, rheumatoid arthritis synovial fibroblasts (RASFs) isolated from the joint of the patients were used to evaluate the suppressive effects of calycosin (CAL), a compound derived from the Chinese medicinal herb Radix Astragali, on the expression of pro-inflammatory cytokines in RASFs. The results demonstrated that increased mRNA expression levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-25 (IL-25), interleukin-33(IL-33) were significantly inhibited by CAL. Furthermore, the compound obviously suppressed IL-6 and IL-33 secretion. The key inflammatory mediator, cyclooxygenase-2 (COX-2) was significantly attenuated by CAL. A mechanistic study showed that the antioxidant enzymes heme oxygenase-1 (HO-1), NAD(P)H dehydrogenase quinone 1(NQO1) and Nrf2 of RASFs were markedly activated by CAL. Furthermore, CAL potentiated the accumulation of sequestosome 1 (SQSTM1, p62) and the degradation of Kelch-like ECH-associated protein 1 (Keap1), thereby inducing Nrf2 translocation from the cytoplasm to the nucleus. Thus, CAL suppresses the expression of pro-inflammatory cytokines via p62/Nrf2-linked HO-1 induction in RASFs, which suggests that the compound should be further investigated as a candidate anti-inflammatory and anti-arthritic agent.

Topics: Anti-Inflammatory Agents; Antioxidants; Arthritis, Rheumatoid; Cell Nucleus; Cells, Cultured; Cytokines; Cytoplasm; Fibroblasts; Gene Expression; Heme Oxygenase-1; Humans; Inflammation; Isoflavones; NF-E2-Related Factor 2; RNA-Binding Proteins; RNA, Messenger

Rheumatoid arthritis (RA) is a chronic inflammatory disease that will affect quality of life and, working efficiency, and produce negative thoughts for patients. Current therapy of RA is treated with disease-modifying antirheumatic drugs (DMARDs). Although most of these treatment methods are effective, most patients still have a pleasant experience either due to poor efficacy or side effects or both. Interleukin-6 receptor (IL6R) is important in the pathogenesis of RA. In this study, we would like to detect the potential candidates which inhibit IL6R against RA from traditional Chinese medicine (TCM). We use TCM compounds from the TCM Database@Taiwan for virtually screening the potential IL6R inhibitors. The TCM candidate compound, calycosin, has potent binding affinity with IL6R protein. The molecular dynamics simulation was employed to validate the stability of interaction in the protein complex with calycosin. The analysis indicates that protein complex with calycosin is more stable. In addition, calycosin is known to be one of the components of Angelica sinensis, which has been indicated to have an important role in the treatment of rheumatoid arthritis. Therefore, calycosin is a potential candidate as lead compounds for further study in drug development process with IL6R protein against rheumatoid arthritis.

Topics: Antirheumatic Agents; Arthritis, Rheumatoid; Humans; Isoflavones; Medicine, Chinese Traditional; Molecular Docking Simulation; Molecular Dynamics Simulation; Receptors, Interleukin-6