Antinociceptive and Anti-inflammatory Effects of Methanolic Extract of Laurencia caspica

Abstract

Introduction: Seaweeds are valuable resources for the discovery of efficient and safe drugs for pain treatment. In the present investigation, we evaluated the antinociceptive and anti-inflammatory properties of, methanolic extract of Laurencia caspica, a red algae, in mice models. Methods: The analgesic effect of methanolic extract of L. caspica was assessed by hot-plate and acetic acid-induced writhing tests in male Swiss albino mice (weight = 20-25 g). The anti-inflammatory activity of methanolic extract of L. caspica was also evaluated by formalin-induced ear edema and xylene-induced paw edema tests. Results: The total flavonoid content of the extract was estimated as 0.0537 mg quercetin/g extract. Both first and second phases of the nociception were significantly inhibited at a dose of 120 mg/kg of methanolic extract of L. caspica. The observed anti-inflammatory effect was dose-dependent. Acetic acid-induced writhing test and hot plate test showed that the extract significantly reduced pain in all evaluated doses (15, 30, 60, and 120 mg/kg). The antinociceptive activity of the methanolic extract was significantly reduced by naloxone (4 mg/kg). Moreover, the extract significantly reduced paw edema at the dose of 120 mg/kg in all the animals. Conclusion: Methanolic extract of L. caspica exhibited central analgesic effect, as well as anti-inflammatory activity probably due to the presence of constituents like flavonoids and triterpenoids.