Acanthopanax senticosus inhibits nitric oxide production in murine macrophages in vitro and in vivo.

Excess nitric oxide (NO) production has been implicated in inflammatory diseases. The present study investigated the inhibitory effect of the stem bark extract of Acanthopanax senticosus (A. senticosus) on NO production in murine macrophages in vitro and in vivo. In vitro exposure of RAW264.7 cells to 1, 10, 50, 100, 250, 500 and 1000 microg/mL of A. senticosus extract significantly suppressed NO production induced by lipopolysaccharide (LPS) and interferon gamma (IFN-gamma) in a dose-dependent manner. In vitro exposure of mouse resident peritoneal macrophages to 1, 10, 100 and 1000 microg/mL of A. senticosus extract significantly suppressed NO production induced by LPS and IFN-gamma in a dose-dependent manner. In vivo administration of A. senticosus extract (50, 100 and 200 mg/kg) to KM mice dose-dependently inhibited LPS and IFN-gamma induced production of NO in isolated mouse peritoneal macrophages ex vivo. Exposure to A. senticosus extract had no effect on cell viability and systemic toxicity. The results demonstrated that the stem bark extract of A. senticosus extract inhibits NO production in murine macrophages in vitro and in vivo.