Curcumin Inhibits the PERK-eIF2<i>α</i>-CHOP Pathway through Promoting SIRT1 Expression in Oxidative Stress-induced Rat Chondrocytes and Ameliorates Osteoarthritis Progression in a Rat Model

<div>Curcumin promoted the expression of SIRT1 and inhibited the activation of the PERK-eIF2<i>α</i>-CHOP pathway. (a, b) Immunofluorescence staining of SIRT1 and quantitation of the number of chondrocytes positive for SIRT1 in different groups. Markedly increased green bright puncta indicated the upregulation of SIRT1 protein expression (bar: 10 <i>μ</i>m). (c) The mRNA expression levels of SIRT1 was assessed by real-time PCR analysis. (d, e) The protein expression levels of SIRT1 and PERK-eIF2<i>α</i>-CHOP pathway-related biomarkers were assayed by western blot analysis. 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Oxidative Medicine and Cellular Longevity

fig4

Figure 4

Figure 4: Curcumin Inhibits the PERK-eIF2<i>α</i>-CHOP Pathway through Promoting SIRT1 Expression in Oxidative Stress-induced Rat Chondrocytes and Ameliorates Osteoarthritis Progression in a Rat Model 

Figure 4 | Curcumin Inhibits the PERK-eIF2α-CHOP Pathway through Promoting SIRT1 Expression in Oxidative Stress-induced Rat Chondrocytes and Ameliorates Osteoarthritis Progression in a Rat Model 