Resveratrol Attenuates Copper-Induced Senescence by Improving Cellular Proteostasis

Figure 5

Resveratrol attenuates copper-induced BiP upregulation but has no effect on eIF2 phosphorylation or HSP90 and HSP70 expression. (a) Phosphorylated eukaryotic translation initiation factor 2 (p-eIF2) and (b) immunoglobulin binding protein (BiP), heat shock protein (HSP) 90, and HSP70 protein relative levels were determined by western blot at 72 h after the removal of 350 μM CuSO₄ (or Na₂SO₄, for controls) in fibroblasts that were allowed to recover in the presence or absence of resveratrol (5 or 10 μM). Representative blots are depicted and densitometric quantification is plotted assuming that protein levels of each analysed protein in control cells without resveratrol equal 1. Ponceau S staining was used to normalize protein loading. Data represent mean ± SEM of at least three independent experiments. ; ; and , for the comparisons between the indicated groups.

(a)

(b)