Tauroursodeoxycholic Acid Protects Nucleus Pulposus Cells from Compression-Induced Apoptosis and Necroptosis via Inhibiting Endoplasmic Reticulum Stress

Figure 6

ER stress was triggered in compression-induced NP cell death. (a) Electron microscope photographs of NP cells stimulated by compression for different durations. Control group (A) without exposure to compression. Experimental groups stimulated for (B) 9 h, (C) 18 h, and (D) 36 h. Morphological changes in the endoplasmic reticulum (arrowheads) could be observed by electron microscopy at 26500x. (b) The Western blot results of ER-stress-related biomarkers p-PERK, p-eIF2α, and p-IRE1. (c), (d), and (e) show the quantitative analysis of expression level of ER-stress-related biomarkers p-PERK, p-eIF2α, and p-IRE1. Results are presented as the fold change in 9, 18, and 36 h groups relative to that in 0 h group (, , and versus 0 h control).

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