sirolimus and caffeic-acid-phenethyl-ester

To investigate apoptosis of osteoarthritic (OA) chondrocytes stimulated with different inhibitors targeting tumor necrosis factor-alpha (TNFα) pathway, we isolated first passage chondrocytes from OA patients and then treated them with the inhibitors in combination with TNFα, and then collected the stimulated chondrocytes for Western blotting. Chondrocytes from OA patients expressed cleaved caspase-3 and PARP, suggesting apoptotic background. We here, validated that 10 ng/ml of TNFα couldn't induce more chondrocytes apoptosis. PI3K inhibitor LY294002 or NF-κB inhibitor CAPE, but not mTOR inhibitor rapamycin and MEK1/2 inhibitor U0126 in combination with TNFα could facilitate apoptosis. CAPE-induced more apoptosis could be explained by c-FLIP downregulation more than cIAP1 upregulation. And, we showed the first time that PI3K-NF-κB pathway, but not mTOR pathway could prevent chondrocytes apoptosis induced by a pro-apoptotic factor TNFα and call for attention while trying to inhibit NF-κB as a therapeutic target.

Topics: Aged; Apoptosis; Butadienes; Caffeic Acids; Caspase 3; Cells, Cultured; Chondrocytes; Chromones; Female; Humans; Middle Aged; Morpholines; NF-kappa B; Nitriles; Osteoarthritis; Phenylethyl Alcohol; Phosphoinositide-3 Kinase Inhibitors; Poly(ADP-ribose) Polymerases; Sirolimus; TOR Serine-Threonine Kinases; Tumor Necrosis Factor-alpha