Inducible Activity of Ginger Rhizome (Zingiber Offifinale Rosc.) on the mRNA Expression of Macrophage-Inducible Nitric Oxide (NO) Synthase and NO Production in a Macrophage Cell Line, RAW264.7 Cells
We have investigated the effect of Zingiber offifinale Rosc. (ZOR) on macrophage-inducible nitric oxide (NO) synthase (macNOS) mRNA expression and NO production in RAW264.7 cells, a murine macrophage cell line; 100 μg/ml ZOR can induce macNOS mRNA expression, but induction effects at a dose below 10 μg/ml were weak or negligible. Kinetic studies showed that macNOS mRNA can be detected from 4 hours to 24 hours after dosing, with a peak at 8 hours. In accordance with the induction of macNOS mRNA expression, NO concentrations increased from 3.4 μM at 2 hours to almost 150 μM at 24 hours, reflecting a longer period of macNOS mRNA expression. The activity of ZOR can be considered to contribute, at least in part, to the beneficial effects of ZOR through the macNOS-mediated activation of the biodefense mechanism.