Fig. 4

Poldip2 mediates cytokine upregulation by hypoxia in astrocytes. Astrocytes were cultured in control conditions or exposed to hypoxia and glucose deprivation for 4 h. Cells were returned to control conditions for the indicated times before extraction of protein or RNA. a Poldip2 protein expression was quantified by western blotting and densitometry. The bar graph represents means ± SEM of six independent experiments normalized to β-actin. Two-way ANOVA *p < 0.05 vs. normoxia. b Poldip2 mRNA was measured by quantitative RT-PCR. Bar graphs represent means ± SEM of ten independent experiments normalized to RPL. c TNFα and IL-6 mRNAs were measured by quantitative RT-PCR. Bar graphs represent means ± SEM of four independent experiments normalized to B2M. One-way ANOVA *p < 0.05 vs. normoxia. d Downregulation of Poldip2 protein after siRNA transfection was verified by western blotting. e Astrocytes were transfected with siNegative (siNeg, non-silencing control) or siPoldip2 before exposure to normoxic or hypoxic conditions (4 h), followed by recovery for 6 h. TNFα and IL-6 mRNAs were measured by quantitative RT-PCR. Bars represent means ± SEM of four independent experiments normalized to B2M. Two-way ANOVA *p < 0.05; **p < 0.01; ***p < 0.001 vs. normoxia