MEK2−/− BMDMs were transfected with HIF-1α or scrambled siRNA. 24 h post-transfection, cells were incubated with/without LPS for 6 h or 24. (A) Total cellular protein (of siRNA transfected cells) were subjected to Western blot analysis using antibodies against HIF-1α, pro IL-1β or β-actin. (B) Densitometric values expressed as fold increase of the ratio of HIF-1α/β-actin. (C) Densitometric values expressed as fold increase of the ratio of pro IL-1β/β-actin. (D) Conditioned media were collected for IL-1β analyses via ELISA. Targeted down regulation of HIF-1α resulted in a significant decrease of IL-1 β in response to LPS (p < 0.05). Data are presented as relative gene expression levels from three independent transfections each performed in triplicates. Data are representative results of three independent experiments each performed in triplicates. Using ANOVA Mann-Whitney U test, * signifies a p value <0.05, while ** signifies a p value <0.001, and error bars indicate SEM.