Fig. 4.

Effects of 7-ketocholesterol (7KCHO) on CHOP and GRP78 mRNA expression in MC3T3-E1 cells, with or without N-acetylcysteine (NAC).

MC3T3-E1 cells were seeded into 6-well plates (1.0 × 10⁴ cells per well), and cultured until reaching 90–95% confluence. The cells were pre-incubated with or without NAC (5.0 mM) for 24 h, and 7KCHO at indicated concentrations was added. CHOP and GRP78 expression was determined by reverse transcription PCR. (A and C) Production of CHOP in the presence of 7KCHO with or without NAC. (B and D) Production of GRP in the presence of 7KCHO with or without NAC. Data are presented as mean ± SD from three independent experiments. †p < 0.05, ‡p < 0.01; Student's t-test. *p < 0.05, **p < 0.01; one-way ANOVA followed by Bonferroni multiple comparison test.