5-Fluorouracil prevents lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells by inhibiting Akt-dependent nuclear factor-κB activation

The effect of 5-fluorouracil (5-FU) on the production of nitric oxide (NO) in macrophages was examined by using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. 5-FU at non-toxic concentrations significantly inhibited NO production in LPS-stimulated RAW 264.7 cells. The inhibition by 5-FU was mediated by attenuated expression of an inducible NO synthase protein and mRNA. 5-FU inhibited the activation of nuclear factor (NF)-kappaB and the subsequent nuclear translocation. Furthermore, 5-FU inhibited the phosphorylation of Akt, an upstream molecule of NF-kappaB signaling. 5-FU did not affect a series of mitogen-activated protein kinases. Therefore, 5-FU was suggested to inhibit the LPS-induced NO production in activated macrophages through preventing Akt-dependent NF-kappaB activation.