To study the therapeutic effects of different processed products and extracts of Morinda officinalis root in rat adjuvant-induced arthritis (AA) model, and to explore the possible mechanism.
AA model in SD rats was established, then the arthritic rats were randomly divided into seven groups such as model, Tripterygium Glycosides Tablet (TGT), morinda with xylem, morinda, salt-steamed morinda, licorice-processed morinda, morinda EtOAc extract, morinda n-BuOH extract, H₂O residue, total polysaccharides and control groups. The paw edema and arthritis indexes were observed, and the contents of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-2 and INF-γ in AA rats serum were detected by ELISA.
Morinda processed by salt and n-BuOH extract could reduce paw swelling and levels of TNF-α, IL-1β, IL-6 and INF-γ in AA rats serum, which followed by morinda EtOAc extract. The differences were significant compared with the model group (P < 0.05 or P < 0.01).
Salt-steamed morinda and morinda n-BuOH extract have the best curative effect, followed by morinda EtOAc extract. Reducing TNF-α, IL-1β, IL-6 and INF-γ contents in serum may be the mechanism of drug treatment of rheumatoid arthritis.