Anti-nociceptive and anti-inflamatory activity of olive fruit extract

Abstract

In Iranian traditional medicine, olive has been reported to have analgesic and anti-inflamatory effects. In the present study the anti-nociceptive and anti-inflamatory effects of olive fruit has been studied. In this study the methanolic and aqueous extract of the fruit with HER (Herbal to Extract Ratio) of 4.96% and 4.84% has been used and analgesic effect of this extract has been compared with a non-steroid analgesic, sodium salicylate, effect. Formalin test was employed in order to evaluate the effect of olive extract on chronic and acute pain. For evaluating the anti-inflamatory effect, the paw inflamation model was used. All experiments were performed on male Sprague-Dawley rats. The aqueous extract of olive fruit at 450 mg/kg and 600 mg/kg doses and methanolic extract at 600 mg/kg doses had significant effect on chronic pain and none of these extracts had any effect on acute pain. The induced analgesia by extract of the fruit is not mediated by the opioid system, because naloxone did not reverse the analgesic effect of aqueous extract. Aqueous extract of olive fruit at 600 mg/kg dose has significant anti-inflammatory effect. Comparing the analgesic activity of the aqueous extract of olive fruit with sodium salicylate showed that this extract is half as potent as sodium salicylate. Olea europea fruit possesses anti-inflammatory and anti-nociceptive effects in the chronic pain. It's anti-nociceptive effects is comparable to those of salicylates. The anti-nociceptive effect obtained from the extract is not conducted via the opioid receptors and most probably, other mechanisms including the biosynthetic prostaglandins pathways are involved. Since the olive plant contains flavonoids, which have cyclooxygenase and lipoxygenase inhibitory effects, the anti-inflamatory effects of the extracts are suggested to be due to the presence of flavonoids.