Research Paper Volume 16, Issue 12 pp 10216—10238

Figure 3. EGR1 regulates apoptosis and ECM synthesis in NPCs. (A) NPCs were transfected with 25 nM CTR siRNA or EGR1 siRNA-1 for 24 hours and then treated with 50 μM TBHP for 24 hours before protein extraction. The protein expression of Bax, Bcl-2, aggrecan, and collagen II was determined by western blotting. (B–E) Quantitative analysis of Bax, Bcl-2, aggrecan, and collagen II protein levels. (F) Representative flow cytometry images showing that EGR1 siRNA protected NPCs from TBHP-induced apoptosis. (G) Quantitative analysis of the NPC apoptosis rate. (H) NPCs were transfected with 5 μg of the EGR1 expression plasmid or the corresponding control vector. After 48 hours, the cells were treated with 50 μM TBHP for 24 hours. Total cellular proteins were extracted, and the expression of Bax, Bcl-2, aggrecan, and collagen II was determined by western blotting. (I–L) Quantitative analysis of Bax, Bcl-2, aggrecan, and collagen II protein levels. (M) Representative flow cytometry images showing that EGR1 overexpression increases TBHP-induced apoptosis in NPCs. (N) Quantitative analysis of the NPC apoptosis rate. The data are expressed as the mean ± SD (n = 3). ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, ^****p < 0.0001.