Glucocorticoids Augment the Chemically Induced Production and Gene Expression of Interleukin-1α through NF-κB and AP-1 Activation in Murine Epidermal Cells

Abstract

To clarify the mechanism of the glucocorticoid-induced augmentation of skin response, we attempted to demonstrate the modulatory effect of glucocorticoids on the regulation of cytokines produced by keratinocytes stimulated with various chemicals in vitro. Haptens, irritants, and a superantigen (staphylococcal enterotoxin B) induced a significant release of interleukin-1alpha and tumor necrosis factor alpha, but not interleukin-10, from a murine keratinocyte cell line, Pam 212 cells. Glucocorticoids (10(-6)-10(-12) M) significantly augmented the production of interleukin-1alpha by Pam 212 cells at both the protein and mRNA levels when stimulated by either haptens or irritants, but not by staphylococcal enterotoxin B, whereas glucocorticoids alone had no effect. In contrast, glucocorticoids had no effect on the production of tumor necrosis factor alpha and interleukin-10 by chemically stimulated Pam 212 cells. Electrophoretic mobility shift assays revealed that chemical stimulation induced NF-kappaB activation in Pam 212 cells; however, augmented NF-kappaB activation by 10(-6)-10(-8) M of glucocorticoids was observed in Pam 212 cells stimulated by both haptens and irritants, but not by staphylococcal enterotoxin B. Furthermore, pyrrolidine dithiocarbamate inhibited the hapten-induced interleukin-1alpha production and NF-kappaB expression by Pam 212 cells. Pyrrolidine dithiocarbamate did not completely abrogate the hapten-induced interleukin-1alpha production augmented by glucocorticoids, however. To determine the effect on transcription factors other than NF-kappaB, AP-1 activity was examined by electrophoretic mobility shift assays. Hapten was founded to induce AP-1 activation in Pam 212 cells. In addition, AP-1 activation was augmented in the hapten-stimulated Pam 212 cells in the presence of 10(-8)-10(-10) M of glucocorticoids. The augmented inflammatory reaction by glucocorticoids may therefore reflect the augmentation of interleukin-1alpha production by keratinocytes mediated through the NF-kappaB and AP-1 pathway.

Budesonide, but not tacrolimus, affects the immune functions of normal human keratinocytes

“…It has also been demonstrated that glucocorticoids (0.1-1000 nM) by themselves could augment the production of IL-1a by PAM 212 cells (murine epithelial cell line) at both the protein and mRNA levels after 6 h of coincubation. When these cells were stimulated for 24 h with haptens or irritants, which alone increased the IL-1a production, glucocorticoids synergistically enhanced the effect [27,28]. NF-nB activation was also revealed in parallel with these observations; nevertheless, Lukiw et al showed inhibition of DNA binding of NF-nB by 100 nM budesonide epimer R and dexamethasone in keratinocytes activated by IL-1h or platelet-activating factor (PAF) [15].…”

FK506 (Tacrolimus) Inhibition of Intracellular Production and Enhancement of Interleukin 1α through Glucocorticoid Application to Chemically Treated Human Keratinocytes

“…The present results clearly demonstrate IL-1 ␣ production of human normal KCs to differ from that of the murine KC cell line Pam in which IL-1 ␣ , following various stimuli, is secreted into the supernatant [4] . But in normal human newborn KCs, it is not secreted into the supernatant but stored in their cytosols.…”

“…Human newborn KCs were cultured with 0.1 m M TNBS (Wako Pure Chemicals Ltd., Osaka, Japan) and in the presence or absence of 10 -6 to 10 -14 M hydrocortisone (Banyu Pharmaceutical Co., Tokyo, Japan), 10 -6 to 10 -14 FK506 (Fujisawa Pharmaceutical Co., Tokyo, Japan), and further application of FK506 to TNBS-treated KCs with 10 -10 M hydrocortisone [4] (and see the results), in KBM (without growth factor supplements) for 24 h in a CO 2 incubator at 37 ° C.…”

“…Keratinocytes (KCs) are crucial for the initial phase of contact hypersensitivity and contact irritation reactions due to their release of cytokines such as IL-1 [3,4] . These cytokines are multifunctional so that their roles in the skin and epidermal cells are diffi cult to determine exactly.…”

“…These cytokines are multifunctional so that their roles in the skin and epidermal cells are diffi cult to determine exactly. M has recently been shown to enhance the chemically (2,4,6-trinitrobenzene sulfonic acid sodium salt, TNBS) induced production and gene expression of IL-1 ␣ through activation of nuclear factor B and activator protein 1 following hapten application in murine epidermal Pam cells [4] . IL-1 ␣ may induce angiogenesis by activating VEGF (vascular endothelial growth factor) [5] expressed in KCs via interactions of infl ammatory cells with endothelial cells.…”