Fig. 3.

NFκB-dependent gene expression is inhibited by SAH. (A) Expression of an NFκB-luciferase reporter construct in inhibited by SAH. HepG2 cells were co-transfected with plasmids encoding an NFκB-luciferase reporter and β-galactosidase under the control of the CMV promoter. 24 hours after transfection, the cells were pre-treated for 2 hours with either medium (DMEM) or 500 µM adenosine and homocysteine (A+H), then either stimulated with 10 ng/ml TNF or left unstimulated for 3 hours. Luciferase activity was normalized to β-galactosidase activity and expressed as a percent of the value in DMEM (control) cells. (B) HepG2 cells were pre-treated with medium alone (DMEM) or 500 µMAdo+Hcy (A+H), then treated with 10 ng/ml TNF were indicated for 3 hours. RNA was isolated and analyzed by real time RT-PCR as described in the Methods. (C) Primary human hepatocytes were pre-treated with 4 mMAdo+Hcy (A+H) or medium alone, then treated with 100 ng/ml for 3 hours. RNA was isolated and analyzed as in panel (B). a- Significantly different (p<0.05) compared to medium alone. b- Significantly different (p<0.05) compared to TNF alone.