Anti-arthritic effects of total flavonoids from Juniperus sabina on complete freund's adjuvant induced arthritis in rats

Context: Twigs and leaves of Juniperus sabina L. have been traditionally used as the medicinal herb in China for the treatment of many ailments including rheumatoid arthritis (RA). Aims: To confirm the therapeutic effect of total flavonoids from J. sabina (JSTF) on RA-induced by Complete Freund's Adjuvant (CFA) in rats. Settings and Design: Wistar rats (200 ± 20 g) were immunized by intradermal injection of 0.1 mL of CFA into the right hind metatarsal footpad. JSTF was administered orally at the dose of 125,250 and 500 mg/kg on 14 days after the induction of adjuvant arthritis. Tripterygium glycoside (20 mg/kg) was used as a positive control. Paw swelling, arthritic score, body weight loss, serum cytokines, inflammatory mediators, and histological change were measured. Results: We found that JSTF could ameliorate paw swelling of CFA rats, and significantly inhibit arthritic score (P < 0.05). The overproduction of tumor necrosis factor alpha and interleukin 1beta were remarkably suppressed in the serum of JSTF (125,500 mg/kg) treated rats (P < 0.05). Histopathological studies also showed a marked decrease of synovial inflammatory infiltration and synovial lining hyperplasia in the joints of JSTF-treated animals. Six flavonoids were isolated and from JSTF by various chromatographic methods and identified as follows: Catechin, quercitrin, isoquercitrin, isoscutellarein 7-O-β-D-xylopyranoside, isoscutellarein 7-O-β-D-xylopyranose-(1 → 3)-α-L-rhamnoside, and rutin. Conclusions: These results suggest the potential therapeutically effect of JSTF as an anti-arthritis agent toward CFA-induced arthritis in rats, and verified therapeutic applications of J. sabina on RA in folk medicine.