In the present study, the in vivo anti-inflammatory activity of Agrimonia pilosa Ledeb (AP) ethanol extract was confirmed in experimental animal models, including xylene‑induced ear edema in mice and carrageenan‑induced paw edema in rats. Tiliroside, the major component of AP extract, was isolated and purified by high‑performance liquid chromatography. The anti-inflammatory mechanism of tiliroside was then examined using lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells. An MTT assay was used to determine cytotoxicity and a Griess assay was used to determine nitric oxide (NO) production. Concentration levels of tumor necrosis factor‑α (TNF‑α) and interleukin‑6 (IL‑6) were determined by enzyme‑linked immunosorbent assay. Protein expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase‑2 (COX‑2), phosphorylated (p)‑extracellular signal‑regulated kinase (ERK) 1/2, p‑c‑Jun N‑terminal kinases (JNK), p‑p38 and inhibitor of κB‑α were detected by western blot analysis. AP ethanol extract was revealed to inhibit xylene‑induced ear edema in mice and carrageenan‑induced paw edema in rats. Tiliroside significantly suppressed the overproduction of NO (P<0.01), but revealed no notable inhibition of the release of TNF‑α and IL‑6. In addition, tiliroside significantly downregulated the elevated expression levels of iNOS and COX‑2 induced by LPS (P<0.01). The phosphorylation of JNK and p38 proteins were also significantly inhibited (P<0.01), however, tiliroside exhibited no obvious inhibition on the phosphorylation of ERK 1/2 and the degradation of IκB‑α protein. In conclusion, the anti-inflammatory molecular mechanism of tiliroside may involve the downregulation of iNOS and COX‑2 protein expression levels, and the inactivation of mitogen-activated protein kinase (MAPK)/JNK, in addition to the MAPK/p38 signaling pathway.

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