Anti-inflammatory effect of Geranium thunbergii on lipopolysaccharide-stimulated RAW 264.7 cells

Geranium thunbergii is a perennial plant commonly used as an oriental medicine for prevention of diarrhea, constipation, and gastrointestinal disorders. However, its anti-inflammatory effect has not been evaluated thus far. Therefore, the present study aimed to investigate the anti-inflammatory effect of G. thunbergii. In this study, G. thunbergii extracted with methanol; this methanol extract was further partitioned using various solvents, and G. thunbergii ethyl acetate fraction (GTEF) was obtained. To determine the anti-inflammatory activity of G. thunbergii, the effects of GTEF on nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 cells were evaluated. GTEF suppressed NO production in a dose-dependent manner without any toxic effects. In addition, western blotting was performed to examine the effect of GTEF on expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggest that GTEF as a phytoextract may be useful for the prevention or treatment of inflammation.