Evaluation of Antinociceptive and Anti-Inflammatory Activities of Solvent Fraction of the Roots ofEchinops keberichoMesfin (Asteraceae) In Mice Model

Background Since ancient times, pain and inflammation have been treated using herbal remedies, which are essentially a stockroom of phytochemical components. Due to the numerous adverse effects of the already available anti-pain and anti-inflammatory medications, the search for new potential pharmaceuticals used to relieve pain and inflammation from natural sources is an ongoing process. The present study was therefore, aimed at investigating the antinociceptive and antiinflammatory activities of the solvent fractions of the roots of E. kebericho M. in mice model. Methods Successive maceration was used as a method of extraction using solvents of increasing polarity: methanol and water. The crude extract was then further fractionated using distilled water, ethyl acetate, and chloroform. Each solvent fraction was then evaluated for its peripheral analgesic activities using an acetic acid-induced writing test and central analgesic activities using the hot plate method. The acute and chronic anti-inflammatory activities of the solvent fractions were detected using carrageenan induced paw edema and cotton pellet ear granuloma respectively. The detected doses were 100mg/kg, 200mg/kg, and 400mg/kg. The positive control groups received ASA (150mg/kg) for the writing test, morphine (10mg/kg) for the hot plate method, diclofenac Na for carrageenan induced paw edema and dexamethasone (10mg/kg) for granuloma, while the negative control group received distilled water. Result EA fraction at all test doses employed (100mg/kg, 200mg/kg and 400mg/kg) showed statistical significant (p < 0.05, p < 0.01, p < 0.001 respectively) analgesic effects in both chemical and thermal induced pain stimuli in dose dependant manner. Likewise, EA fraction also exhibited anti-inflammatory activities on carrageenan induced paw edema and cotton pellet-induced granuloma in a dose-dependent manner. The AQ fraction on the other hand produced statistical significant (p < 0.05, p < 0.012) analgesic and anti-inflammatory activities at the doses of 200mg/kg and 400mg/kg, while the CH fraction exhibited statistical significant (p < 0.05) analgesic and anti-inflammatory activity at the dose of 400mg/kg. Conclusion In general, the data obtained from the present study elucidated that the solvent fractions possessed significant analgesic and anti-inflammatory activities and recommended further investigations.