Fig. 5: Autophagy selectively degrades p62 protein in LECs.

A Representative confocal images of LECs from 18 patients with different grades senile cataract stained with LC3 antibody (red), p62 antibody (cyan), TUNEL labeling (green), and DAPI (blue). The laser intensity and pinhole were fixed for all samples. Yellow dotted irregular circles indicate cells with LC3 puncta. Scale bar, 30 μm. B Correlation between p62 fluorescence intensity and LC3 fluorescence intensity in LECs from patients with different grades senile cataract stained as in A (More than 380 cells from four groups were analyzed; each symbol represents one cell). p = 0.0007 by Pearson’s correlation analysis. C Immunoblots showing the protein levels of p62 in WT and ATG7 KO HLE-B3 cells stimulated with 200 μM H₂O₂ for indicated times, in the presence or absence of 100 μM CHX. D Real-time PCR results for the relative mRNA levels of p62 in WT and ATG7 KO HLE-B3 cells stimulated with 200 μM H₂O₂ for indicated times. The mRNA levels are normalized by those in cells without H₂O₂ treatment. E Heatmap of expression levels (log₂fold-change) of representative Nrf2 pathway genes in ATG7 KO and WT HLE-B3 cells. Data show up-regulated (red) or down-regulated (blue) gene expressions after treated with 200 μM H₂O₂ compared with untreated. F Immunoblots showing protein level of Nrf2 in whole-cell lysates (WCL), nuclear and cytosolic extracts of WT and ATG7 KO HLE-B3 cells exposed to 200 μM H₂O₂ for indicated times. G Viability of WT and ATG7 KO HLE-B3 cells after knockdown of Nrf2 expression exposed to 200 μM H₂O₂ for 24 h. Quantitative data are presented as mean ± SD from four independent experiments (*p < 0.05, **p < 0.01, unpaired Student’s t test).