Fig. 4.

Effect of PRL on transcription of antioxidant genes in rat astrocytes. Rat cortical astrocytes were incubated in the absence or presence of 10 nM prolactin (PRL) for 4, 8, 16 or 24 h, and changes in mRNA levels of a superoxide dismutase 1 (Sod1), b superoxide dismutase 2 (Sod2), c glutathione peroxidase 1 (Gpx1), and d catalase were measured by quantitative RT-PCR. Data were initially normalized using the Hprt housekeeping gene as an internal control and then to the corresponding gene expression in the 4 h vehicle-treated group (Veh). Data in a, b, c and d are means ± SEM of four independent experiments (n = 4). Unpaired two-tailed Student’s t-test. Rat cortical astrocytes were incubated in the absence or presence of either 10 nM PRL, 100 μM STAT3 inhibitor S3I-201 or both for 24 h. mRNA levels of e Sod1, f Sod2, and g Gpx1 were measured by quantitative RT-PCR. Data were initially normalized using the Hprt housekeeping gene as an internal control and then to the corresponding gene expression in the vehicle-treated group. Data in e, f, and g are means ± SEM of four independent experiments (n = 4). Protein expression of SOD1 (h), SOD2 (i), and GPX1 (j) was detected by Western blotting in 5, 10 or 20 μg of astrocyte lysate, respectively; and quantified by using β-tubulin as loading control. Data are means ± SEM of (h, j) four (n = 4) or (j) three (n = 3) independent experiments. One-way ANOVA followed by Tukey’s test. *p < 0.05, **p < 0.001 versus vehicle or indicated group. For GPX1 protein, Kruskal–Wallis’s test followed by Dunn’s test