FIG. 4.

Effect of SIRT1 overexpression on cytokine-induced NO production and iNOS mRNA and protein expressions. Control or SIRT1-overexpressing RIN cells were treated with IL-1β alone or IL-1β and IFN-γ for 24 h, and nitrite production (A) and iNOS mRNA (B) and protein (C) expressions were determined. The results of three independent experiments are expressed as the means ± SE. *P < 0.05, **P < 0.01 vs. untreated pBABE; ##P < 0.01 vs. IL-1β + IFN-γ–treated pBABE; $P < 0.05, $$P < 0.01 vs. untreated DN-SIRT1.