Chemical Composition of Bawei Longzuan Granule and Its Anti-Arthritic Activity on Collagen-Induced Arthritis in Rats by Inhibiting Inflammatory Responses.

Bawei Longzuan granule (BLG) is a representative Zhuang medicine preparation. The present work aims to characterize the chemical constituents of BLG and evaluate its anti-arthritic activity. The major chemical constituents of BLG were tentatively identified by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS), which revealed the presence of some alkaloids (e. g., magnoflorine, sinomenine and nitidine) and flavonoids (e. g., hesperidin, diosmin and sinensetin) that may be partly responsible for the anti-arthritic effect of BLG. In addition, the collagen-induced arthritis (CIA) model in rats was induced by intradermal injection of bovine collagen-II in complete Freund's adjuvant at the base of tail. The CIA rats received oral administration of BLG (1.25, 2.5 and 5 g/kg) for 30 days. Then, various indicators were determined to evaluate its anti-arthritic activity, including paw swelling, arthritic score, body weight, knee joint pathology, thymus index and spleen index. Additionally, the serum levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-1β, IL-6, IL-4 and IL-10 were measured to determine the underlying mechanisms. The results showed that BLG efficiently ameliorated the severity of arthritis in CIA rats by decreasing paw swelling and arthritis score and improving the histological lesions of knee joint. Moreover, the serum levels of several pro-inflammatory cytokines (i. e., IL-1β, TNF-α, IL-6 and IFN-γ) were downregulated, whereas two anti-inflammatory factors (i. e., IL-4 and IL-10) were upregulated after BLG administration. These results indicated that BLG possessed promising therapeutic effect on collagen-induced arthritis by inhibiting inflammatory responses. BLG can be used as a complementary or alternative traditional medicine to treat rheumatoid arthritis.