Figure 2

TUDCA reduces proinflammatory stimuli-induced nitrite production in glial cell cultures through transcriptional inhibition of iNOS. Nitrite production was determined in (A) microglial cells and (B) astrocytes. Cells were pretreated with TUDCA for 2 h and the proinflammatory stimuli was added and incubated for an additional 24 h. The results represent the mean of the percentage related to control ± SD of at least six experiments (microglial cells) and at least four experiments (in astrocytes) in triplicate. The effect of TUDCA on proinflammatory stimuli-induced luciferase activation of the rat iNOS-pGL3 firefly reporter was studied in (C) microglial cells and (D) astrocytes. SV40-pRL Renilla reporter was used as a control for transfection efficiency. The results represent the mean of the fold induction related to the control ± SD of at least four experiments in triplicate. The expression of the mRNA for iNOS was determined by qPCR in (E) microglial cells and (F) astrocytes. The expression of mRNA for β-actin and the expression of mRNA for 36B4 were used as loading control for astrocytes and microglial cells, respectively. The results represent the mean of the ratio between the expression of mRNA for iNOS/expression of mRNA for β-actin or 36B4 ± SD of at least three experiments in triplicate.*P <0.05, **P <0.01.