Analgesic and Antioxidant Potential of the Leaves of Mikania scandens (L.) Willd.

: The present study was designed to evaluate analgesic and antioxidant potential of the hydromethanol extract of the leaves of Mikania scandens (L.) Willd. The analgesic activity was determined for its central and peripheral pharmacological actions using hotplate and tail immersion method and acetic acid-induced writhing test in mice respectively. The extract, at the dose of 250 and 500 mg kg−1, produced a significant (p<0.05) increase in pain threshold in hotplate and tail immersion methods in a dose dependent manner. In acetic acid-induced writhing test, the extract (500 mg kg−1) produced a maximum of 53.73% inhibition (p<0.001) of writhing reaction compared to the reference drug Diclofenac-Na (76%). The extract was also investigated for its antioxidant action using 1,1-Di-Phenyl-2-Picryl-Hydrazyl (DPPH) radical scavenging, Nitric Oxide (NO) scavenging and reducing power assays. A dose dependent scavenging of DPPH radical and NO was observed with good reducing power with the extract. In DPPH radical scavenging assay, the IC50 value of the extract was 375.40 μg mL−1 while the IC50 value for the reference ascorbic acid was 55.89 μg mL−1. The IC50 values of the extract and ascorbic acid were 220.43μg mL−1 and 125.10 μg mL−1, respectively in NO scavenging assay. The findings of the study suggest that the extract from Mikania scandens has strong analgesic and antioxidant effects.