Antinociceptive and Anti-Inflammatory Effects of Geum iranicum Khatamsaz Methanol Extract in Mice

Background and objectives: Traditionally, Geum species from Rosaceae family have been used for treating inflammatory disorders. Geum iranicum Khatamsaz is endemic to Iran. The aim of this study was to investigate the antinociceptive and anti-inflammatory activities of Geum iranicum methanol extract G. iranicum methanol extract using classical models. Methods: The methanol extract of G. iranicum roots was evaluated for antinociceptive activity by acetic acid-induced writhing, formalin and hot-plate tests in male Swiss albino mice. The anti-inflammatory effect was investigated by Carrageenan-induced paw edema method. Results: The extract significantly inhibited both the first and second phases of formalin-induced nociception in mice at the dose of 100 mg/kg compared to the control group. In acetic acid-induced writhing test and hot plate method, the extract significantly reduced pain behavior in all doses (25, 50 and 100 mg/kg). The antinociceptive activity of the extract was significantly reduced by naloxone (4 mg/kg). The anti-inflammatory activity of the extract was found to be dose dependent. The extract at the dose of 100 mg/kg exhibited significant reduction of paw edema in all surveyed times. Conclusion: The results showed that the methanol extract of G. iranicum roots possessed central analgesic activity via modulation of opioid receptors as well as antiinflammatory activity. The observed effects could be attributed to the presence of constituents like triterpenoids, eugenol, sucrose and tannins in the extract.