IL1B and rheumatoid arthritis: These results are related to those of previous studies that ameliorated the effects of OA; Liu et al. reported that treatment with the CQA-rich fraction of Periploca forrestii (CQAF) significantly blocked IL-1β-induced expression of nitric oxide, PGE2, COX-2, and iNOS in MH7A cells (human rheumatoid arthritis synovial cell line) [44].