Figure 5.

ZLF inhibits apoptosis and protects human NP cell degeneration. NP cells of G2 tissues were pretreated with ZLF (20 µM) for 24 h. Then, NP cells without or with ZLF pretreatment were cultured with 100 µM of H₂O₂ for 24 h. (A) The chemical structural formula of ALF. (B and C) The protein expression level of collagen II was determined by (B) IF (magnification, x400) and (C) quantification analysis. (D and E) The protein expression levels of collagen II, ATF4, CHOP and caspase-9 were determined by (D) WB and (E) quantification analysis. (F and G) The ratio of apoptotic cells was analyzed by (F) flow cytometry and (G) quantification analysis. The values are mean ± SD of three independent experiments (n=3). (^*P<0.05, ^**P<0.01, ^***P<0.001, compared with 100 µM H₂O₂). ATF4, activating transcription factor 4; CHOP, C/EBP homologous protein; WB, western blot; NP, nucleus pulposus; IF, immunofluorescence.