Cytokines, tumor necrosis factor-alpha and interleukin-1beta, differentially regulate apoptosis in osteoarthritis cultured human chondrocytes.
Osteoarthritis Cartilage
; 14(7): 660-9, 2006 Jul.
Article
em En
| MEDLINE
| ID: mdl-16492401
ABSTRACT
OBJECTIVE:
This study addresses the effects of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) on cell death in human chondrocytes.METHODS:
Osteoarthritis (OA) human chondrocytes stimulated with Actinomycin-D (ActD) were used as a cellular apoptotic model. Caspase family mRNA expression and protein synthesis were analyzed by the ribonuclease protection assay and Western-blot, respectively. Cell viability and apoptosis were evaluated using the 3-[4,5-dimethylthiazol-2yl] 2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, respectively. Prostaglandin E2 (PGE2) and nitric oxide (NO) were evaluated by enzyme-linked immunosorbent assay (ELISA) and the Griess method, respectively.RESULTS:
TNF-alpha and IL-1beta differentially affected the pattern of caspase mRNA expression by human chondrocytes. TNF-alpha induced a gradual increase in caspase-1 and -8 mRNA levels that was not seen with IL-1beta. The time sequence of caspase-3 and -7 inductions by TNF-alpha differs from that induced by IL-1beta. Cell viability was not modified by TNF-alpha or IL-1beta in cultured chondrocytes. Then, we employed ActD as a model to facilitate cell death. Treatment with TNF-alpha and ActD (TNF-alpha/ActD) increased cell death induced by ActD (23%). Treatment with IL-1beta and ActD (IL-1beta/ActD) did not modulate ActD-induced cell death. Similarly, IL-1beta/ActD did not induce an increase in the activation of caspase-3 and -7 and poly (ADP-ribose) polymerase (PARP) cleavage observed by the incubation with TNF-alpha/ActD. These different effects were not due to bcl-2 or mcl-1 levels. Inhibition of PGE2 synthesis by indomethacin increased the cell death induced by IL-1beta/Act-D (59%). An inhibitor of caspase-8 significantly reduced only the TNF-alpha/ActD-induced cell death (58%).CONCLUSION:
TNF-alpha and IL-1beta differentially regulate the apoptotic pathway in human chondrocytes. This difference is dependent on PGE2 and caspase-8 levels.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Contexto em Saúde:
6_ODS3_enfermedades_notrasmisibles
Problema de saúde:
6_musculoskeletal_diseases_rheumatic_disorders
Assunto principal:
Osteoartrite
/
Condrócitos
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Osteoarthritis Cartilage
Assunto da revista:
ORTOPEDIA
/
REUMATOLOGIA
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Espanha