The Role of Unfolded Protein Response in Human Intervertebral Disc Degeneration: Perk and IRE1-α as Two Potential Therapeutic Targets

Figure 3

Inflammation triggers UPR and impairs biological activity of NPCs. The expression of UPR gene in NPCs treated by IL-1 and TNF-α synergistically without/with 4-PBA was analyzed by real-time PCR (a) and western blot (b). (c) Cell proliferation was evaluated by the CCK-8 assay at days 1 to 7 after IL-1 and TNF-α synergistically without/with 4-PBA treatment. (d) The expression of Agg, Col2, and SOX9 following the exposure of NPCs to IL-1 and TNF-α synergistically without/with 4-PBA was confirmed by western blot analysis. β-Actin was used as an internal control. The representative results were from three independent experiments. The error bars represent the SD from the mean values. , .

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