Fig. 5

NST-1s attenuates CIA through the suppression of osteoclastogenesis. a Suppression of cytokines involved in the destruction of joints in NST-1s-treated mice with autoimmune arthritis ankle joints. Tissues from CIA mice and NST-1s-injected mice were obtained at 14 weeks and stained immunohistochemically with specific antibodies to tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa-B (RANK) and RANK ligand (RANKL). b Murine monocytes obtained from the femur and tibia were cultured with macrophage colony-stimulating factor (M-CSF) and RANKL to induce osteoclastogenesis. TRAP-positive multinucleated cells were counted in the culture dishes with or without 100 µM of NST-1s. c, d The relative mRNA levels of osteoclastogenesis-related markers (TRAP, integrin beta chain beta 3, cathepsin K and calcitonin receptor), RIPK1 and RIPK3 were evaluated using reverse transcription polymerase chain reaction. Osteoclasts were cultured with NST-1s 100 μM for 72 h and cell viability was analyzed by CCK-8 analysis. *p < 0.05; **p < 0.01; ***p < 0.001