Effects of celecoxib on the expression of osteoprotegerin, energy metabolism and cell viability in cultured human osteoblastic cells

Clinical and Experimental Rheumatology

C. Perka¹  G.-R. Burmester¹  S. Lach¹  R. Tripmacher¹  F. Buttgereit¹  P. Kolar¹  P. Maschmeyer¹  R. Dziurla¹  D. Krocker¹  G. Matziolis¹  T. Gaber¹ 

关键词: Osteoblasts;    celecoxib;    osteoprotegerin;    oxygen consumption;    glucose transporter-1;    hypoxia-inducible-factor-1α;    cell viability.;   

DOI  :  

学科分类：医学（综合）

来源: Pacini Editore SpA

【 摘 要 】

BACKGROUND AND OBJECTIVES:The selective COX-2 inhibitor celecoxib is widely used to treat pain and inflammation in rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis. The drug has well-known important effects on immune cells but its direct and/or indirect influence on osteoblasts has not yet been explored in detail. This study aimed to investigate the dose-dependent effects of celecoxib on cell viability, energy metabolism and bone remodeling processes in cultured human osteoblastic cells.METHODS:Primary human osteoblasts and MG-63 cells were incubated with celecoxib (2, 10, 50µM). Cell viability and apoptosis were determined by trypan blue, 7AAD and Annexin-V staining. Effects on cellular oxygen consumption were measured amperometrically using a Clark electrode. mRNA expression of GLUT-1 and OPG was determined by RT-PCR; OPG protein secretion by ELISA and HIF-1α protein expression by immunoblotting. RESULTS:While celecoxib at a concentration of 2 and 10µM showed only marginal effects, a suprapharmacological concentration of 50µM influenced viability and energy metabolism, as well as OPG expression and secretion of osteoblastic cells. Cell viability was significantly reduced by celecoxib treatment. Celecoxib at 50µM stimulated oxygen consumption significantly. Corresponding experiments with the protonophore FCCP suggest that this effect is due to mitochondrial uncoupling. After 24h, GLUT-1 mRNA expression was significantly increased. HIF-1α protein was not expressed under any of our experimental conditions. We also showed that celecoxib at 50µM significantly inhibits OPG protein secretion leading to a compensative increase of mRNA expression.CONCLUSIONS:Pronounced effects of celecoxib on cell viability (reduction), oxygen consumption (stimulation), GLUT-1 mRNA expression (stimulation) and OPG protein secretion (inhibition) in osteoblastic cells were observed only at 50µM–a concentration not reached by therapeutic doses giving plasma concentrations less than 10µM. On the contrary, celecoxib at 2 and 10µM showed only marginal effects, suggesting that celecoxib administration is probably safe with respect to bone metabolism in cases requiring potent treatment of pain and inflammation. However, higher intracellular concentrations, which might occur through accumulation, necessitate investigations with high concentrations.

【 授权许可】

Unknown