Antinociceptive and anti-inflammatory effects of aqueous extract of Chenopodium opulifolium schrad leaves

AIM: Chenopodium opulifolium is a specie of the Chenopodiaceae commonly used as vegetables in local diet and for treating different ailment in Uganda. This study was conducted to evaluate the antioxidant, antinociceptive and anti-inflammatory effects of the aqueous extract of C. opulifolium leaves (AECO). MATERIALS AND METHODS: The dried leaf of the plant was extracted by maceration in water. Qualitative and quantitative phytochemical analysis, antioxidants, and membrane stabilizing effects were determined in the extract. The extract was then investigated for acute toxicity, antinociceptive (writhing, hot plate and open field test), and anti-inflammatory (egg albumin-induced paw edema) effects in rodents. RESULTS: Phytochemical analysis revealed the presence of alkaloids, tannins, phlobatannins, flavonoids, and saponins in AECO. Total caffeic acid derivatives and total flavonoids content were 91.7 mgCAE/g sample and 94.7 mgRE/g sample, respectively. AECO demonstrated antioxidant effects in both 1,1-diphenyl-2-picryl-hydrazyl and NO assays. Significant membrane stabilizing activity was observed in both the heat and hypotonic solution-induced lysis of erythrocytes. The acute toxicity test showed that AECO (5000 mg/kg) did not cause any significant change in behavior or death in rats. AECO (100-400 mg/kg) produced a significant antinociceptive effect in both the writhing and hot plate tests, but no significant reduction in the locomotory activity in mice. Furthermore, the extract significantly (P < 0.05) reduced egg albumin-induced rat paw edema by 44.2%, 44.5%, and 51.2%, respectively, after 120 min. CONCLUSION: The results showed that C. opulifolium extract possesses significant antioxidant, antinociceptive and anti-inflammatory effects, and these affirm the reasons for its folkloric use.