In vitro anti-inflammatory activity of the Artemisia montana leaf ethanol extract in macrophage RAW 264.7 cells

Artemisia is one of the largest genera of the family Asteraceae or Compositae, consisting of 500 species. Some Artemisia species, such as Artemisia afra, A. sacrorum, and A. annua, have been widely used as traditional medicine to treat inflammatory and malarial diseases. However, the biological activity of A. montana has not been broadly studied. Therefore, in this study, we investigated the anti-inflammatory activity of A. montana leaf extract (ALE) and its molecular mechanisms in lipopolysaccharide-activated RAW 264.7 cells. Non-cytotoxic concentrations of ALE significantly reduced the expression of inducible nitric oxide (NO) synthase and cyclooxygenase-2, resulting in the decrease in NO and prostaglandin E₂. Moreover, ALE inhibited the production of tumour necrosis factor-α and interleukin-6. We also observed that ALE treatment repressed mitogen-activated kinase pathways by inhibiting the phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38, suggesting that ALE is a therapeutic candidate to treat inflammatory diseases.