trichostatin-a and Dermatitis--Allergic-Contact

We have shown the induction of histone deacetylase 3 (HDAC3) in antigen-stimulated rat basophilic leukemia cells via NF-κB. We investigated the role of HDAC3 in allergic skin inflammation. We used a BALB/c mouse model of triphasic cutaneous anaphylaxis (triphasic cutaneous reaction; TpCR) and passive cutaneous anaphylaxis (PCA) to examine the role of HDAC3 in allergic skin inflammation. Triphasic cutaneous reaction involved induction of HDAC3 and was mediated by HDAC3. HDAC3 showed an interaction with FcεRIβ. Trichostatin A (TSA), an inhibitor of HDAC(s), disrupted this interaction. Cytokine array analysis showed that the down-regulation of HDAC3 led to the decreased secretion of monocyte chemoattractant protein 1 (MCP1). FcεRI was necessary for induction of HDAC3 and MCP1. ChIP assays showed that HDAC3, in association with Sp1 and c-Jun, was responsible for induction of MCP1 expression. TSA exerted a negative effect on induction of MCP1. HDAC3 exerted a negative regulation on expression of HDAC2 via interaction with Rac1. The down-regulation of HDAC3 or inactivation of Rac1 induced binding of HDAC2 to MCP1 promoter sequences. TSA exerted a negative effect on HDAC3-mediated TpCR. The BALB/c mouse model of PCA involved induction of HDAC3 and MCP1. HDAC3 and MCP1 were necessary for PCA that involved ear swelling, enhanced vascular permeability, and angiogenesis. Recombinant MCP1 enhanced β-hexosaminidase activity and histamine release and also showed angiogenic potential. TSA exerted a negative effect on PCA. Our data show HDAC3 as a valuable target for the development of allergic skin inflammation therapeutics.

Topics: Animals; Capillary Permeability; Cell Line; Chemokine CCL2; Dermatitis, Allergic Contact; Dinitrofluorobenzene; Female; Gene Expression Regulation; Histone Deacetylase 2; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Male; Mice; Mice, Inbred BALB C; Neovascularization, Physiologic; Neuropeptides; Passive Cutaneous Anaphylaxis; Promoter Regions, Genetic; Protein Binding; rac GTP-Binding Proteins; rac1 GTP-Binding Protein; Rats; Rats, Sprague-Dawley; Receptors, IgE; Transcriptional Activation

Histone deacetylases (HDACs) influence chromatin organization, representing a key epigenetic regulatory mechanism in cells. Trichostatin A (TSA), a potent HDAC inhibitor, has anti-tumor and anti-inflammatory effects. Allergic contact dermatitis (ACD) is a T-cell-mediated inflammatory reaction in skin and is regulated by epidermal Langerhans cells (LCs).. The aim of this study was to investigate if TSA treatment prevents 2,4-dinitrofluorobenzene (DNFB)-induced ACD in mice and regulates epidermal LCs and other immune cells during ACD development.. ACD was induced by sensitizing and challenging with DNFB topically. Mice were treated intraperitoneally with TSA or vehicle DMSO as a control every other day before and during induction of ACD. The ear swelling response was measured and skin biopsies from sensitized skin areas were obtained for histology. Epidermal cells, thymus, spleen and skin draining lymph nodes were collected for immune staining.. TSA treatment ameliorated skin lesion severity of DNFB-induced ACD. The percentages of epidermal LCs and splenic DCs as well as LC maturation were significantly reduced in TSA-treated mice. However, TSA treatment did not significantly affect the homeostasis of conventional CD4(+) and CD8(+) T cells, Foxp3(+)CD4(+) regulatory T cells, iNKT cells, and γδ T cells in thymus, spleen and draining lymph nodes (dLNs). Furthermore, there were no significant differences in IL-4 and IFN-γ-producing T cells and iNKT cells between TSA- and DMSO-treated mice.. Our findings suggest that TSA may ameliorate ACD through the regulation of epidermal LCs and HDACs could serve as potential therapeutic targets for ACD and other LCs-related skin diseases.

Topics: Animals; Dermatitis, Allergic Contact; Dinitrofluorobenzene; Forkhead Transcription Factors; Histone Deacetylase Inhibitors; Hydroxamic Acids; Langerhans Cells; Mice; Mice, Inbred C57BL; Receptors, Antigen, T-Cell, gamma-delta; T-Lymphocytes