Fig. 4

Depletion of β-arrestin2 aggravates apoptosis of astrocytes stimulated by IL-6. A Cell viability was detected treated with different concentration of IL-6 (0, 100, 200, 300, 400, 500 ng/mL) for primary astrocytes. B, D Apoptosis rate of WT and Arrb2^−/− astrocytes were detected by flow cytometry (n = 3). C, E PI/Hoechst staining to observe cell apoptosis stimulated by IL-6 (300 ng/ml). Scale bar: 20 μm n = 7. F Protein levels of Bcl-2 and BAX were detected in WT and Arrb2^−/− astrocytes. G, H Protein levels of p-JAK/JAK and p-STAT3/STAT3 were detected in WT and Arrb2^−/− astrocytes or transfected with Arrb2 siRNA. I After extraction of nucleus protein from astrocytes, the levels of p-STAT3/STAT3 were detected. J Immunofluorescence staining p-STAT3 in WT and Arrb2^−/− astrocytes. p-STAT3: Red; Hoechst: Blue; Scale bar: 20 μm. A Bars and error flags represent the means ± SEM of at least three independent experiments; statistically significant by Student t test; *P < 0.05, **P < 0.01, ***P < 0.001 VS WT Control group or Arrb2^−/− untreated group. ^#P < 0.05, ^##P < 0.01 VS corresponding IL-6 stimulated group. D, E Data were denoted as mean ± SEM using two-way ANOVA, then combined with Tukey to assess the differences between groups. ***P < 0.001 VS WT Control group; ^###P < 0.001