RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Atropa acuminata has been widely used in traditional medicine against arthritis and several associated inflammatory disorders. AIM OF THE STUDY: The present study was undertaken to investigate the anti-arthritic activities of ethanolic extract of Atropa accuminata (AAEE) and to explore the probable mechanism of action. MATERIALS AND METHODS: The anti-arthritic activity of AAEE was evaluated within a dose range of 125-500 mg/kg b.w. in adjuvant induced-arthritis in male wistar rats. An array of pro-inflammatory mediators (PGE2 NO, IL-1ß and LTB4) and T-cell-mediated cytokines (IL-2, TNF-a, IFN-c, IL-4, IL-10, IL-12, IL-17, IL-6) were assayed in arthritic paw tissue homogenate of the treated animals. In addition the effects on arthritic lesions, changes in body weight; haematological (Hb, ESR, WBC and RBC) and biochemical parameters (SOD, GSH, GR) and the serum markers (CRP, RF) were also observed. RESULTS: Significant anti-arthritic activity was observed for AAEE in the polyarthiritis test both in the developing and developed phase of the disease. This was associated with dose dependant suppression of pro-inflammatory mediators (PGE2, NO, IL-1ß and LTB4)., Th1-Th17 cytokines (IL-2, TNF-α, IFN-γ, IL-12, IL-17, IL-6) and upregulation of Th2 cytokines (IL-4 and IL-10). AAEE was also observed to protect rats against the primary and secondary arthritic lesions, body weight changes and haematological perturbations. In addition, inhibitory effects of AAEE on biochemical parameters and the serum markers further confirmed that it reduced signs on chronic inflammatory responses. CONCLUSION: The present investigation therefore suggested that AAEE is a potent anti-arthritic agent. The multipronged attack on the inflammatory mediators and T-helper cytokines and strong potency of AAEE may have relevance for inhibition of the chronic inflammatory responses in arthritis.