Oleuropein treatment decreased cellular senescence in synoviocytes and bone cells isolated from patients. (A) Cx43 protein levels analyzed by western blot in synoviocytes treated with 10 μM oleuropein for 2 h (n=7 independent experiments, P=0.0313). (B) Treatment of synoviocytes with 10 μM of oleuropein for 7 days detected by SA-βGal activity (n=4 independent experiments, P<0.0001). (C) p16 mRNA levels of synoviocytes treated with 10 μM oleuropein for 2 h. Data were normalized to HPRT-1 levels (n= 4 independent experiments, P<0.0001). On the right, mRNA levels of IL-1ß, IL-6 and COX-2 of synoviocytes cultured in normal medium (DMEM 10% FBS) and exposed to 10 μM oleuropein for 2 h. Data were normalized to HPRT-1 levels. N=4 independent experiments, P<0.0001 (IL-1ß), P=0.0024 (IL-6), P=0.0025 (COX-2). (D) Cx43 protein levels analyzed by western blot in bone cells treated with 10 μM oleuropein for 2 h (n=4 independent experiments, P=0.0319). (E) 10 μM of oleuropein treatment for 7 days reduces senescence levels in bone cells as detected by SA-βGal and flow cytometry (n=3 independent experiments, P=0.0149). (F) p16 mRNA expression of bone cells treated with 10 μM oleuropein for 2 h. Data were normalized to HPRT-1 levels (n= 4 independent experiments, P=0.002). On the right, mRNA levels of IL-1ß, IL-6 and COX-2 of bone cells cultured in normal medium (DMEM 10% FBS) exposed to 10 μM oleuropein for 2 h. Data were normalized to HPRT-1 levels. N=3-4 independent experiments. P=0.0463 (IL-1ß), P=0.0077 (IL-6), P=0.0002 (COX-2). Data is expressed as mean±SD, Student’s t test; *P<0.05, **P<0.01 and ***P<0.0001.