Effects of Prunus tomentosa total flavone on adjuvant-induced arthritis

To investigate the effect and mechanism of Prunus tomentosa total flavone (PTTF) treatment on adjuvant arthritis (AA), the rat AA model was induced by a single intradermal injection of complete Freund's adjuvant (CFA) into the left ankle. The degree of lateral ankle swelling was measured by the foot volume method. The rats were sacrificed, the thymus and spleen were taken out and the organ index was calculated. Paraffin sections of the left ankle specimens were fabricated and the organization forms of the articular cartilage and synovium were observed. Kits were used to measure the serum nitric oxide (NO), NO synthase (NOS) and prostaglandin E2 (PGE(2)) content. After 18days, the swelling degree of ankle joints in the dexamethasone group, the PTTTF 7.0 and 14mg/kg groups were significantly lower than that in the model group (P < 0.05). The organ index in the dexamethasone group and the PTTF group were not statistically significantly different from that in the normal group (P > 0.05). Compared to the CFA model control group, the dexamethasone group and the PTTF each group had significantly less synovial proliferation and congestion. In these groups, the joint surface was smooth, with no obvious structural damage; the serum NO, NOS and PGE(2) were significantly lower than in the control group (P < 0.01). The results indicated that PTTF at 7 and 14mg/kg can effectively alleviate the secondary inflammatory response to AA in rats' lateral ankle. The mechanism may be related to inhibition of the secretion of NO, PGE(2) and NOS.