Signal pathways JNK and NF-κB, identified by global gene expression profiling, are involved in regulation of TNFα-induced mPGES-1 and COX-2 expression in gingival fibroblasts

• Published in: BMC genomics Vol. 11; no. 1; p. 241
• Main Authors: Båge, Tove, Lindberg, Johan, Lundeberg, Joakim, Modéer, Thomas, Yucel-Lindberg, Tülay
• Format: Journal Article
• Language: English
• Published: London BioMed Central 15.04.2010; BMC
• Subjects: ACTIVATED PROTEIN-KINASES; AGGRESSIVE PERIODONTITIS; Animal Genetics and Genomics; Bioengineering; Biomedical and Life Sciences; Bioteknik; E-2 BIOSYNTHESIS; INFLAMMATORY-BOWEL-DISEASE; Life Sciences; MESSENGER-RNA; Microarrays; Microbial Genetics and Genomics; PHOSPHOLIPASE A; Plant Genetics and Genomics; PROSTAGLANDIN-E SYNTHASE; Proteomics; Research Article; RHEUMATOID-ARTHRITIS; TECHNOLOGY; TEKNIKVETENSKAP; TERMINAL KINASE; TUMOR-NECROSIS-FACTOR; PGE2; PGE2 Production; Gingival Tissue; Differentially Express; Gingival Fibroblast
• ISSN: 1471-2164; 1471-2164
• DOI: 10.1186/1471-2164-11-241

Background Prostaglandin E 2 (PGE 2 ) is involved in several chronic inflammatory diseases including periodontitis, which causes loss of the gingival tissue and alveolar bone supporting the teeth. We have previously shown that tumor necrosis factor α (TNFα) induces PGE 2 synthesis in gingival fibroblasts. In this study we aimed to investigate the global gene expression profile of TNFα-stimulated primary human gingival fibroblasts, focusing on signal pathways related to the PGE 2 -synthesizing enzymes prostaglandin E synthases (PGES), as well as the upstream enzyme cyclooxygenase-2 (COX-2) and PGE 2 production. Results Microarray and western blot analyses showed that the mRNA and protein expression of the inflammatory induced microsomal prostaglandin E synthase-1 (mPGES-1) was up-regulated by the cytokine TNFα, accompanied by enhanced expression of COX-2 and increased production of PGE 2 . In contrast, the expression of the isoenzymes microsomal prostaglandin E synthase-2 (mPGES-2) and cytosolic prostaglandin E synthase (cPGES) was unaffected by TNFα treatment. Using oligonucleotide microarray analysis in a time-course factorial design including time points 1, 3 and 6 h, differentially expressed genes in response to TNFα treatment were identified. Enrichment analysis of microarray data indicated two positively regulated signal transduction pathways: c-Jun N-terminal kinase (JNK) and Nuclear Factor-κB (NF-κB). To evaluate their involvement in the regulation of mPGES-1 and COX-2 expression, we used specific inhibitors as well as phosphorylation analysis. Phosphorylation analysis of JNK (T183/Y185) and NF-κB p65 (S536) showed increased phosphorylation in response to TNFα treatment, which was decreased by specific inhibitors of JNK (SP600125) and NF-κB (Bay 11-7082, Ro 106-9920). Inhibitors of JNK and NF-κB also decreased the TNFα-stimulated up-regulation of mPGES-1 and COX-2 as well as PGE 2 production. Conclusion In the global gene expression profile, the enrichment analysis of microarray data identified the two signal transduction pathways JNK and NF-κB as positively regulated by the cytokine TNFα. Inhibition of these TNFα-activated signal pathways reduced the expression of mPGES-1 and COX-2 as well as their end product PGE 2 in gingival fibroblasts. The involvement of the signal pathways JNK and NF-κB in the regulation of PGE 2 induced by TNFα may suggest these two pathways as possible attractive targets in the chronic inflammatory disease periodontitis.