Analgesic and Anti-Inflammatory Activities of the Ethanolic Extract of Artemisia morrisonensis Hayata in Mice

Abstract

The aim of this study was to investigate the possible analgesic and anti-inflammatory mechanisms of the ethanolic extract of A. morrisonensis Hayata (AM(EtOH)). Two models were employed for evaluation of the analgesic effects: acetic acid-induced writhing response and formalin-induced paw licking. The results demonstrated that AM(EtOH) decreased 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 by λ-carrageenan. AM(EtOH) significantly decreased induced paw edema three to four hours after λ-carrageenan injection. Additionally, the results indicated that the anti-inflammatory mechanism of AM(EtOH) may be due to the declined levels of nitric oxide (NO) and malondialdehyde (MDA) in the edematous paw. Furthermore, AM(EtOH) decreased 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 the AM(EtOH) extract determined p-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 of AM(EtOH) for mice and provided evidence for the ethnobotanical uses of A. morrisonensis in treating inflammatory diseases.

Figure 1

(a) Base peak chromatogram (BPC) from LC-MS of AM_EtOH. (b) Extracted ion chromatogram (EIC) from m/z 134.9 of AM_EtOH; fragment ions were shown as insert. (c) BPC of authentic p-hydroxyacetophenone; fragment ions were shown as insert. All chromatograms were detected in the negative ion mode.

Figure 2

HPLC chromatogram of AM_EtOH detected at 315 nm; p-hydroxyacetophenone is identified at RT = 15.99 min.

Figure 3

Analgesic effects of ethanol extract of AM_EtOH and indomethacin (Indo) on acetic acid-induced writhing response in mice. Each value represents as mean ± SEM (n = 10), *P < 0.05, ***P < 0.001 as compared with the control (Con) group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 4

Analgesic effects of AM_EtOH and indomethacin (Indo) on the (a) early phase and (b) late phase in formalin test in mice. Each value represents as mean ± S.E.M. (n = 10), **P < 0.01, ***P < 0.001 as compared with the control (Con) group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 5

Effects of AM_EtOH and indomethacin (Indo) on hind paw edema induced by λ-carrageenan in mice. Each value represents as mean ± S.E.M. (n = 10), ***P < 0.001 as compared with the λ-carrageenan (Carr) group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 6

Effects of AM_EtOH and indomethacin (Indo) on the tissue COX-2 concentration of edema paw in mice. Each value represents as mean ± S.E.M. (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 7

Effects of AM_EtOH and indomethacin (Indo) on the tissue TNF-α concentration of edema paw in mice. Each value represents as means ± SEM (n = 10), *P < 0.05, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 8

Effects of AM_EtOH and indomethacin (Indo) on the tissue IL-6 concentration of edema paw in mice. Each value represents as means ± SEM (n = 10), *P < 0.05 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 9

Effects of AM_EtOH and indomethacin (Indo) on the tissue NO concentration of edema paw in mice. Each value represents as mean ± S.E.M. (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 10

Effects of AM_EtOH and indomethacin (Indo) on the tissue MDA concentration of edema paw in mice. Each value represents as mean ± S.E.M. (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 11

Effects of AM_EtOH and indomethacin (Indo) on the liver SOD activities in mice. Each value represents as mean ± SEM (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 12

Effects of AM_EtOH and indomethacin (Indo) on the liver GPx activities in mice. Each value represents as mean ± SEM (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)

Figure 13

Effects of AM_EtOH and indomethacin (Indo) on the liver GRd activities in mice. Each value represents as mean ± S.E.M. (n = 10), **P < 0.01, ***P < 0.001 as compared with the Carr group. (One-way ANOVA followed by Scheffe's multiple range test.)