INHIBITION OF IL-1 RELEASE FROM HUMAN MONOCYTES AND SUPPRESSION OF STREPTOCOCCAL CELL-WALL AND ADJUVANT-INDUCED ARTHRITIS IN RATS BY AN EXTRACT OF TRIPTERYGIUM-WILFORDII HOOK

1. It was investigated whether an extract of Tripterygium wilfordii Ho ok f (TW) inhibits IL-1 production by monocytes and suppresses the dev elopment of IL-1-dependent arthritis induced in rats with streptococca l cell wall and adjuvant. 2. TW preferentially inhibited IL-1 alpha an d IL-1 beta production by bacterial lipopolysaccharide (LPS)-stimulate d human monocytes with IC50 of approximately 1 mu g/ml. 3. Oral admini stration of TW dose-dependently suppressed joint swelling and structur al damage in streptococcal cell wall-induced arthritis (ED(50) = 20 mg /kg/day) and in adjuvant-induced arthritis (ED(50) = 46 mg/kg/day for developing and 8 mg/kg/day for established arthritis).