AIMTo investigate the regulatory effects of various anti-inflammatory drugs on both endogenous and TNFalpha-induced NF-kappaB activation as well as the relative biological activity.

METHODSHEK293 cells were cultured in 96-well plate and 6-well plate, treated with meloxicam, indomethacin, dexamethasone and hydrocortisone, without or with 10 ng.mL(-1) TNFalpha for 24 hours. Then cell proliferation was measured by MTT and cell apoptosis was analyzed by pI stain-flow cytometry. HEK293/ kappaB-luc cells transfected stably with pElam-kappaB-luc vector, were cultured in 96-well plate and treated as above. Equal amounts of cell lysates were tested for luciferase activity which represents NF-kappaB activation.

RESULTSEndogenous NF-kappaB activation was present in HEK293 cells and its level can be increased about 2 times by 10 ng.mL(-1) TNFalpha-induction. Dexamethasone (1 x 10(-8) mol.L(-1)) and meloxicam (1 x 10(-7) - 1 x 10(-6) mol.L(-1)) can decrease both endogenous and TNFalpha-induced NF-kappaB activation. Hydrocortisone (1 x 10(-9) mol.L(-1)) increases endogenous NF-kappaB activation but decreases TNFalpha-induced one significantly. No influence of indomethacin on endogenous NF-kappaB activation was observed. However, its influence on TNFalpha-induced NF-kappaB activation is needed for further study. Cell apoptosis was observed after treatment with TNFalpha and 1 x 10(-8), 1 x 10(-6) mol.L(-1) dexamethasone and 1 x 10(-7) mol.L(-1) indomethacin, or only with dexamethasone. No significant effect of these anti-inflammatory drugs on cell proliferation was observed.

CONCLUSIONVarious anti-inflammatory drugs differ in their ability to regulate NF-kappaB activation in HEK293 cells, which indicates that NF-kappaB activation might be a potential useful target to study mechanism and for drug screening.