Fig. 3

Regulation of UPR genes by cytokines/growth factors in human osteoarthritic chondrocytes under H-UPR conditions. Chondrocytes (n = 5–7) were treated with the following factors: Activin A (ActA), TGF-β, PDGF-BB, IL-4, IL-6, and IL-8 (all at 10 ng/ml), IL-1β (100 pg/ml), and TNF-α (5 ng/ml) and processed for RNA extraction and qPCR. Each control (untreated cells) was assigned an arbitrary value of 1 and the effect of the treatment evaluated as fold change over control. Data are expressed as mean ± SEM, and p values assessed by the one-sample t test, comparing the treated chondrocytes to the control