Inverse regulation of the nuclear factor-kappaB binding to the p53 and interleukin-8 kappaB response elements in lesional psoriatic skin.
Nuclear factor-kappaB (NF-kappaB) is an inducible nuclear transcription factor regulating a range of cellular processes. An imbalance of the DNA binding activity of NF-kappaB may, therefore, be part of the pathophysiological mechanisms in psoriasis. The purpose of this study was to determine the NF-kappaB DNA binding activity in psoriatic skin using three different kappaB sites and to determine how DNA binding activity was modulated by the anti-psoriatic drug calcipotriol. By electrophoretic mobility shift assay, we demonstrated that the NF-kappaB DNA binding to the p53 kappaB site was decreased, whereas the NF-kappaB DNA binding to the interleukin-8 (IL-8) kappaB site was increased in lesional psoriatic skin compared with non-lesional psoriatic skin. No regulation was seen on the NF-kappaB DNA binding to the major histocompatibility complex class I kappaB site. These changes were paralleled by a similar decrease in p53 expression and an increase in IL-8 expression in involved psoriatic skin compared with uninvolved skin as determined by quantitative RT-PCR. The alteration in NF-kappaB DNA binding activity was neither accompanied by any change in the expression of the inhibitor kappaB (IkappaB) kinases, IKKalpha, IKKbeta, and IKKgamma nor in the expression of the NF-kappaB inhibitor proteins, IkappaBalpha and IkappaBbeta. Immunofluorescence analysis revealed that p65 was sequestered in the cytoplasm of keratinocytes, whereas p50 exhibited a cytoplasmic as well as a nuclear localization. Interestingly, this distribution of p50 and p65 was similar in lesional and non-lesional psoriatic skin. Topical application of calcipotriol to lesional psoriatic skin for 4 d resulted in increased NF-kappaB binding to the p53 kappaB site and decreased NF-kappaB binding to the IL-8 kappaB site. Taken together, our data demonstrate that the NF-kappaB DNA binding activity is regulated in a specific manner in psoriatic skin depending on the kappaB sites investigated, and that topical treatment of psoriatic skin normalizes the abnormal NF-kappaB binding activity seen in lesional psoriatic skin.
Johansen
Claus
C
Department of Dermatology, Marselisborg Hospital, University of Aarhus, Aarhus C, Denmark. clausoglotte@hotmail.com
Flindt
Esben
E
Kragballe
Knud
K
Henningsen
Jeanette
J
Westergaard
Majken
M
Kristiansen
Karsten
K
Iversen
Lars
L
D000279:Administration, Cutaneous; D000328:Adult; D015153:Blotting, Western; D002117:Calcitriol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002478:Cells, Cultured; D004247:DNA / Q000378:metabolism; D003879:Dermatologic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D024202:Electrophoretic Mobility Shift Assay; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D051550:I-kappa B Kinase; D020672:I-kappa B Proteins / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism*; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011565:Psoriasis / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D020218:Response Elements; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
D003879:Dermatologic Agents; D020672:I-kappa B Proteins; D016209:Interleukin-8; D016328:NF-kappa B; D020033:Protein Isoforms; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; C055085:calcipotriene; D004247:DNA; D017346:Protein Serine-Threonine Kinases; C496559:CHUK protein, human; D051550:I-kappa B Kinase; C496560:IKBKB protein, human; C496565:IKBKE protein, human; D002117:Calcitriol