Analgesic and Anti-Inflammatory Activities of the Ethanolic Extract ofArtemisia morrisonensisHayata in Mice

Abstract

The aim of this study was to investigate the possible analgesic and anti-inflammatory mechanisms of the ethanolic extract ofA. morrisonensisHayata (AMEtOH). Two models were employed for evaluation of the analgesic effects: acetic acid-induced writhing response and formalin-induced paw licking. The results demonstrated thatAMEtOHdecreased writhing response for both the acetic acid assay and the licking time in the formalin test. The anti-inflammatory effect was evaluated by paw edema of mice induced byλ-carrageenan.AMEtOHsignificantly decreased induced paw edema three to four hours afterλ-carrageenan injection. Additionally, the results indicated that the anti-inflammatory mechanism ofAMEtOHmay be due to the declined levels of nitric oxide (NO) and malondialdehyde (MDA) in the edematous paw. Furthermore,AMEtOHdecreased the tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels, leading to the reduction of prostaglandins and subsequently alleviated edema. Isolation and purification of theAMEtOHextract determinedp-hydroxyacetophenone to be a major component at 130 mg/g of extract. No mortality was observed in the acute toxicity test given at the dose of 10 g/kg. This study demonstrated the possible mechanisms for the analgesic and anti-inflammatory effects ofAMEtOHfor mice and provided evidence for the ethnobotanical uses ofA. morrisonensisin treating inflammatory diseases.