Inhibition of nuclear factor kappa B and induction of apoptosis in T-lymphocytes by sulfasalazine.
1. Chronic inflammatory diseases have been shown to be associated with NF-kappaB activation and impaired apoptosis of immune cells. The aim of the present study was to investigate if sulfasalazine and its colonic metabolites 5-aminosalicylic acid (5ASA) and sulfapyridine affect NF-kappaB/Rel activation and viability of T-lymphocytes. 2. Sulfasalazine inhibits NF-kappaB/Rel activation in the murine T-lymphocyte cell line RBL5 using electrophoretic mobility shift assays. In transfection assays sulfasalazine treatment for 4 h inhibits kappaB-dependent transcription with an IC50 value of approximately 0.625 mM. 3. Higher doses or prolonged treatment result in cell death of T-lymphocytes in a dose- and time-dependent manner. Cell death is caused by apoptosis as judged by DNA fragmentation, annexin V and Apo 2.7 staining. Induction of apoptosis is a fast event with 50% apoptotic cells after a 4 h incubation with 2.5 mM sulfasalazine. The ED50 value for apoptosis induction after 24 h treatment was approximately 0.625 mM. 4. In contrast, 5ASA and sulfapyridine neither inhibit NF-kappaB/Rel activation nor induce apoptosis in T-lymphocytes at doses up to 5.0 mM. 5. These results demonstrate that sulfasalazine, but not 5ASA or sulfapyridine, strongly inhibits NF-kappaB activation and potently induces apoptosis in T-lymphocytes. Inhibition of NF-kappaB/Rel activation and subsequent clearance of activated T-lymphocytes by apoptosis might thus explain the beneficial effects of sulfasalazine in the treatment of chronic inflammatory disorders.
Liptay
S
S
Department of Pediatrics, University of Ulm, Ulm, Germany.
Bachem
M
M
Häcker
G
G
Adler
G
G
Debatin
K M
KM
Schmid
R M
RM
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D019804:Mesalamine / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013427:Sulfapyridine / Q000494:pharmacology; D012460:Sulfasalazine / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects; D014407:Tumor Cells, Cultured
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016328:NF-kappa B; D012460:Sulfasalazine; D019804:Mesalamine; D013427:Sulfapyridine