Figure 6.

Amelioration of ER stress by PBA abrogates Atg7 ablation-mediated inhibitory effects on osteoblast mineralization in vitro. Primary osteoblasts derived from control and Atg7 cKO mice were cultured with or without 10 mM PBA. (a and b) The expression of ER stress markers were detected by western blot, and the relative phosphorylation of p-ERN1, p-JUN and p-EIF2AK3 was analyzed using ImageJ software. (c) Relative expression of Bglap, Alpl and Runx2 mRNA. (d) Representative images for ALPL and Alizarin red S staining. (e and f) Representative TUNEL labeling images of primary osteoblasts cultured with or without PBA; representative TUNEL-positive cells are indicated by the arrows (quantified in f), and bars: 10 μm. Data are mean ± SD (one-way ANOVA, *P < 0.05, **P < 0.01 cKO vs. Con, # P < 0.05 cKO + PBA vs. cKO).