Fig 2: GR-ß up-regulation, HDAC2 down-regulation and corticosteroid insensitivity induced by IL-17. Human fibroblast MRC5 cells were transfected with Si-IL-17RA or scrambled Si-Ctrl and then incubated with IL-17 (10ng/mL). mRNA was determined by RT-qPCR and protein was determined by western blotting. (A, B) Dexamethasone (10-7 M) reduces collagen I production at both mRNA level (2h) and protein level (6h), but the suppressive effect was hampered by IL-17. Silencing IL-17RA gene restored dexamethasone’s suppressive effect. The GR-ß mRNA expression was up-regulated at 2h (C) and protein was increased at 6h and 12h (D). IL-17 also down-regulated HDAC2 at mRNA and protein level. Silencing IL-17RA gene attenuated IL-17’s effect on GR-ß up-regulation and HDAC2 down-regulation. Bars represent means ± SEM of 6 experiments. Si, small interfering RNA; Ctrl, control; IL, interleukin; IL-17RA, interleukin-17 receptor A; Dex, dexamethasone; GR, glucocorticoid receptor; HDAC2, histone deacetylase 2. *p < 0.05.