Anti-inflammatory and analgesic properties of an ethanolic extract of aerial parts of oxygonum sinuatum in albino mice

Abstract

Oxygonum sinuatum locally called Kafumita bagenda, is traditionally used for relieving pain and inflammation in conditions including tonsillitis, wounds and boils. The study aimed at evaluating the anti-inflammatory and analgesic properties of the ethanolic extract of the aerial parts of this plant in albino mice. Qualitative phytochemical screening was done using procedures adopted by Sofowara and Harborne, with modifications. The animals were randomized into three test groups and two control groups of four animals each. The test groups received 200mg/kg, 400mg/kg and 800mg/kg, respectively of the crude concentrate. Negative and positive control group received 10ml/kg of distilled water and 10mg/kg of diclofenac sodium per os, respectively. The anti-inflammatory effect was tested on egg albumin-induced paw oedema while the analgesic effect was tested using the acetic acid-induced writhing response. The data was analyzed using Microsoft Excel 2013 and significance tested using the student’s t-test at 5% level of significance. The extract (200, 400 and 800 mg/kg orally) significantly (p<0.05) and dose-dependently inhibited egg albumin-induced mouse paw oedema compared with control group. Four hours after administration of egg albumin, the highest dose of the extract (800 mg/kg, p.o.) inhibited oedema formation by 100%. This was comparable to the standard drug, diclofenac sodium (10 mg/kg, p.o.) which also gave an inhibition of 100% at 4 hours. The extract also exhibited a significant dose-dependent analgesic activity in the acetic acid-induced writhing test as evidenced by the reduction in the number of writhes at 200, 400 and 800mg/kg compared to the control. The 800 mg/kg dose produced a similar percentage inhibition of writhing (87.8%) compared to the standard drug diclofenac sodium (87.3%). The results obtained in this study provide some evidence that O. sinuatum contains active substances with potential for relieving pain and inflammation.