Fig. 4: IL-4R and Nrf2 activation in response to IL-4 in vivo and in vitro.

A, B qPCR (A) and western blotting analysis (B) showed elevated IL-4Ra expression in RPE complex from the NaIO3-induced degenerative mice after IL-4 treatment. n = 3. C Representative images of RPE flat-mount sheet revealed that increased IL-4Ra distributed alongside the RPE tight junction marker ZO-1. Scale bar: 20 μm. The hexagonal ZO-1+ cells per field and the percentage of IL-4Rα + ZO-1+ cells and total ZO-1+ cells were calculated for statistics. D Western blotting analysis showed reduction of total and phosphorylated Nrf2 expression in NaIO3 model, while IL-4 treatment induced their elevations. n = 3. E Representative images of cultured RPE cells under oxidative stress insults showing lack of IL-4Rα and phosphorylated Nrf2 expression, which were induced after IL-4 stimulation. Data are shown as mean ± SEM, *P < 0.05, **P < 0.01, ***P < 0.001, n.s: no significance, one-way ANOVA test.