Evaluation of Anti-Inflammatory Activities of a Triterpene β-Elemonic Acid in Frankincense In Vivo and In Vitro

Abstract

The purpose of this research was to extract and separate the compounds from frankincense, and then evaluate their anti-inflammatory effects. The isolated compound was a representative tetracyclic triterpenes of glycine structure according to 1H-NMR and 13C-NMR spectra, which is β-elemonic acid (β-EA). We determined the content of six different localities of frankincense; the average content of β-EA was 41.96 mg/g. The toxic effects of β-EA administration (400, 200, 100 mg/kg) for four weeks in Kunming (KM) mice were observed. Compared with the control group, the body weight of mice, the visceral coefficients and serum indicators in the β-EA groups showed no systematic variations. The anti-inflammatory effects of β-EA were evaluated in LPS-induced RAW264.7 cells, xylene-induced induced ear inflammation in mice, carrageenin-induced paw edema in mice, and cotton pellet induced granuloma formation in rats. β-EA inhibited overproduction of tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein 1 (MCP-1), soluble TNF receptor 1 (sTNF R1), Eotaxin-2, Interleukin 10 (IL-10) and granulocyte colony-stimulating factor (GCSF) in the RAW264.7 cells. Intragastric administration with β-EA (300, 200, and 100 mg/kg in mice, and 210, 140, and 70 mg/kg in rats) all produced distinct anti-inflammatory effects in vivo in a dose-dependent manner. Following treatment with β-EA (300 mg/kg, i.g.), the NO level in mice ears and PGE2 in mice paws both decreased (p < 0.01). In conclusion, our study indicates that β-EA could be a potential anti-inflammatory agent for the treatment of inflammatory diseases.