Primary effect of 1α,25(OH)₂D₃ on IL-10 expression in monocytes is short-term down-regulation.
The biologically most active vitamin D compound, 1α,25-dihydroxyvitamin D₃ (1α,25(OH)₂D₃), influences the status of inflammation by modulating the expression of several cytokine genes. In this study, we have examined the mechanism of transcriptional regulation of interleukin 10 (IL-10) by 1α,25(OH)₂D₃ in lipopolysaccharide (LPS)-treated human monocytes (THP-1). Quantitative PCR showed that IL-10 mRNA expression was significantly down-regulated (2.8-fold) during the first 8h of 1α,25(OH)₂D₃ treatment, while after 48 h it was up-regulated (3-fold). Gel shift and quantitative chromatin immunoprecipitation (ChIP) assays showed that the vitamin D receptor (VDR) binds in a cyclical fashion to a promoter region 1500-1700 bp upstream of the IL-10 transcription start site (TSS) containing two conserved VDR binding sites. Targeting of VDR binding sites by enhancer specific duplex RNAs revealed that only the more distal element is functional and chromosome conformation capture analysis suggested that this region loops 1α,25(OH)₂D₃-dependently to the TSS. Quantitative ChIP and micrococcal nuclease assays also revealed 1α,25(OH)₂D₃-dependent cyclical epigenetic changes and nucleosome remodeling at this promoter region. In conclusion, in LPS-treated THP-1 cells the primary effect of 1α,25(OH)₂D₃ on IL-10 expression is down-regulation, which is achieved via a cyclical recruitment of VDR to the promoter.
Matilainen
Juha M
JM
Department of Biosciences, University of Eastern Finland, FIN-70211 Kuopio, Finland.
Husso
Tiia
T
Toropainen
Sari
S
Seuter
Sabine
S
Turunen
Mikko P
MP
Gynther
Petra
P
Ylä-Herttuala
Seppo
S
Carlberg
Carsten
C
Väisänen
Sami
S
D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects; D056970:Co-Repressor Proteins / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics* / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D034622:RNA Interference; D018167:Receptors, Calcitriol / Q000235:genetics / Q000378:metabolism; D020218:Response Elements / Q000235:genetics; D047488:Retinoid X Receptors / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D024363:Transcription Initiation Site; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000494:pharmacology; D014815:Vitamins / Q000494:pharmacology
D056970:Co-Repressor Proteins; D018167:Receptors, Calcitriol; D047488:Retinoid X Receptors; D014815:Vitamins; C118756:dihydroxy-vitamin D3; D016753:Interleukin-10; D014807:Vitamin D; D008156:Luciferases