Lipopolysaccharide-induced transcriptional activation of interleukin-10 is mediated by MAPK- and NF-kappaB-induced CCAAT/enhancer-binding protein delta in mouse macrophages.
We have previously revealed that LPS can activate transcription of the IL-10 gene promoter through transcription factors Sp1, C/EBPbeta and C/EBPdelta in mouse macrophages. In this study, we determined that NF-kappaB and MAPK signal pathways, including ERK, JNK, and p38, were all involved in LPS-induced IL-10 gene expression. Treatment of cells with the pharmacological inhibitors of ERK, JNK, p38 and NF-kappaB respectively inhibited LPS-induced IL-10 protein expression in a dose-dependent manner. These inhibitors also decreased the LPS-induced IL-10 mRNA expression at a high concentration used. With transient overexpression of the IkappaB expression plasmids, or the dominant negative plasmids of ERK2, JNK, p38 together with reporter vector containing IL-10 promoter region, all four expression plasmids inhibited LPS-induced IL-10 promoter activity individually. It is known that the increase in protein and DNA binding of C/EBPbeta and delta could activate IL-10 gene expression. In this study, we also identified that all four pharmacological inhibitors inhibited the protein expression of C/EBPdelta individually, but not C/EBPbeta. In the presence of all three MAPK inhibitors, or only NF-kappaB inhibitor, LPS-induced protein expression and DNA binding of C/EBPdelta were completely inhibited simultaneously, and LPS-induced expression of IL-10 protein and mRNA was also inhibited totally. Taken together, these results suggested that LPS-induced IL-10 expression was mediated at least through the pathway of NF-kappaB- and MAPK-induced protein expression and DNA binding of C/EBPdelta.
Liu
Yi-Wen
YW
Graduate Institute of Biopharmaceutics, College of Life Sciences, National Chiayi University, Chiayi, Taiwan.
Chen
Chun-Chia
CC
Tseng
Hui-Ping
HP
Chang
Wen-Chang
WC
D000818:Animals; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism; D051743:CCAAT-Enhancer-Binding Protein-delta / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D017930:Genes, Reporter; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D020935:MAP Kinase Signaling System / Q000502:physiology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D047428:Protein Kinase Inhibitors / Q000378:metabolism; D015533:Transcriptional Activation
D022782:CCAAT-Enhancer-Binding Protein-beta; D008070:Lipopolysaccharides; D016328:NF-kappa B; D047428:Protein Kinase Inhibitors; D016753:Interleukin-10; D051743:CCAAT-Enhancer-Binding Protein-delta; D020928:Mitogen-Activated Protein Kinases