trichostatin-a and Asthma

Diverse cellular functions including the regulation of inflammatory gene expression, DNA repair and cell proliferation are regulated by epigenetic changes. Transcriptional co-activators possess intrinsic histone acetyltransferase (HAT) activity, and histone acetylation plays a major role in inflammatory gene expression. Other marks such as histone methylation are also associated with gene induction and gene repression. Recent evidence implicates histone acetylation and methylation as being crucial for the development of tolerance in macrophages and CpG methylation for T regulatory cell development and function. The expression of the enzymes that lay down or remove these epigenetic marks have not been well studied in human airways disease, but reduced HDAC2 expression and activity is reported in lung macrophages, biopsies and blood cells from patients with COPD, severe asthma and smoking asthma. In vitro, inhibitors of histone deacetylases (HDAC) often lead to a further induction of inflammatory gene expression. This is not always the case, however, as HATs and HDACs also target non-histone proteins particularly transcription factors to alter their activity. Furthermore, trichostatin A, an HDAC inhibitor, can reduce inflammation in a murine model of allergic asthma. This effect of HDAC inhibitors may be due to their effects on cell death acting through acetylation of non-histone proteins. The role of epigenetic modifications in inflammatory gene expression and in the control of cell function in the airways is becoming clearer. Targeting specific enzymes involved in this process may lead to new therapeutic agents, in particular, in situations where current anti-inflammatory therapies are currently suboptimal.

Topics: Acetylation; Animals; Asthma; DNA Methylation; Enzyme Inhibitors; Epigenesis, Genetic; Gene Expression Regulation; Histone Acetyltransferases; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Hydroxamic Acids; Immune Tolerance; Inflammation; Pulmonary Disease, Chronic Obstructive; Transcriptional Activation

The upper-airway microbiome is involved in asthma exacerbations despite inhaled corticosteroid (ICS) treatment. Although human genetics regulates microbiome composition, its influence on asthma-related airway bacteria remains unknown.. We sought to identify genes and biological pathways regulating airway-microbiome traits involved in asthma exacerbations and ICS response.. Saliva, nasal, and pharyngeal samples from 257 European patients with asthma were analyzed. The association of 6,296,951 genetic variants with exacerbation-related microbiome traits despite ICS treatment was tested through microbiome genome-wide association studies. Variants with 1 × 10. Genes associated with exacerbation-related airway-microbiome traits were enriched in asthma comorbidities development (ie, reflux esophagitis, obesity, and smoking), and were likely regulated by trichostatin A and the nuclear factor-κB, the glucocorticosteroid receptor, and CCAAT/enhancer-binding protein transcription factors (7.8 × 10. Genes associated with asthma exacerbation-related microbiome traits might influence asthma comorbidities. We reinforced the therapeutic interest of trichostatin A, nuclear factor-κB, the glucocorticosteroid receptor, and CCAAT/enhancer-binding protein in asthma exacerbations.

Topics: Administration, Inhalation; Adrenal Cortex Hormones; Anti-Asthmatic Agents; Asthma; Carrier Proteins; Cytidine Deaminase; Genome-Wide Association Study; Human Genetics; Humans; Minor Histocompatibility Antigens; NF-kappa B

The ovalbumin-induced (OVA) chronic allergic airways murine model is a well-established model for investigating pre-clinical therapies for chronic allergic airways diseases, such as asthma. Here, we examined the effects of several experimental compounds with potential anti-asthmatic effects including resveratrol (RV), relaxin (RLN), L-sulforaphane (LSF), valproic acid (VPA), and trichostatin A (TSA) using both a prevention and reversal model of chronic allergic airways disease. We undertook a novel analytical approach using focal plane array (FPA) and synchrotron Fourier-transform infrared (S-FTIR) microspectroscopic techniques to provide new insights into the mechanisms of action of these experimental compounds. Apart from the typical biological effects, S-FTIR microspectroscopy was able to detect changes in nucleic acids and protein acetylation. Further, we validated the reduction in collagen deposition induced by each experimental compound evaluated. Although this has previously been observed with conventional histological methods, the S-FTIR technique has the advantage of allowing identification of the type of collagen present. More generally, our findings highlight the potential utility of S-FTIR and FPA-FTIR imaging techniques in enabling a better mechanistic understanding of novel asthma therapeutics.

Topics: Animals; Anti-Asthmatic Agents; Asthma; Chronic Disease; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Hydroxamic Acids; Isothiocyanates; Mice; Mice, Inbred BALB C; Ovalbumin; Relaxin; Resveratrol; Spectroscopy, Fourier Transform Infrared; Sulfoxides; Synchrotrons; Treatment Outcome; Valproic Acid

The aim of this study is to investigate the expression pattern of histone deacetylase 9 in peripheral blood of patients with allergic asthma and its regulatory effect on the balance of Th17/Treg cells involved in the pathogenesis of asthma.. flap-Ub promoter-GFP-WRE vector was used to construct the Jurkat-HA-FOXP3 cell line. After histone deacetylase inhibitor-trichostatin A (TSA) treatment, FOXP3 and RORγt expression were detected by real-time-polymerase chain reaction (RT-PCR). BALB/c mice were randomly assigned to control group, TSA treatment and the asthma group. Serum Immunoglobulin E (IgE) was detected with enzyme-linked immunosorbent assay (ELISA), airway inflammation in lung tissue evaluated by haematoxylin/eosin staining, bronchoalveolar lavage fluid (BALF) cell number and differential counted, interleukin (IL)-17A and TGF-β concentrations in BALF measured with ELISA, and expression of RORγt and FOXP3 messenger RNA (mRNA)measured by RT-PCR. Forty-seven patients with asthma were recruited and assigned to intermittent, mild and moderate-severe group. GATA3, IL-4, histone deacetylases (HDAC) 9 mRNA expression level were measured by RT-PCR.. After TSA treatment, FOXP3 mRNA level was upregulated, while RORγt mRNA level was downregulated. FOXP3 protein level was also upregulated by TSA. In vivo, TSA treatment can inhibit IL-17 but promote transforming growth factor-beta production in the BALF of asthma mice, and inhibited the expression of Th17 cells and RORγt mRNA in lung; also can promote Foxp3 mRNA expression. GATA3, IL-4 mRNA expression levels were upregulated in patients with asthma than the healthy control. HDAC9 mRNA expression level was associated with the severity of disease.. The histone deacetylase inhibitor TSA can regulate the balance of Th17/Treg in asthma by regulating the activity of histone deacetylase.

Topics: Animals; Asthma; Cell Line; Disease Models, Animal; Forkhead Transcription Factors; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Mice; Nuclear Receptor Subfamily 1, Group F, Member 3; Random Allocation; Repressor Proteins; T-Lymphocyte Subsets; T-Lymphocytes, Regulatory; Th17 Cells

T lymphocytes, which are characterized by longevity and immune memory, play an important role in airway inflammation in asthma. Here, we assessed the association between immune memory and histone deacetylation and/or acetylation status.. CD4 + CD45RB(low) cells (memory T (Tm)) obtained from the spleens of asthma mice models were co-cultured with glucocorticoids (GCs), trichostatin A (TSA) or anacardic acid (AA) and adoptively transferred to naïve mice. Interleukin (IL)-4, 5 and 13 and IFN-γ concentrations were measured in culture supernatants and bronchoalveolar lavage fluid (BALF). Histone deacetylase (HDAC) and histone acetyltransferase (HAT) activities and the expression of T-bet, GATA-3, HDACs 1-11 and alveolar eosinophilic inflammation index (AEII) were determined in lung tissues.. Culture supernatants and the BALF showed similar cytokine profiles. AA and GCs significantly inhibited HAT activity (P = 0.002 and P = 0.018), whereas TSA inhibited and GCs promoted HDAC activity (P = 0.004 and P = 0.025). HDACs 7, 9 and 10 were upregulated by AA and GCs (all P < 0.032), while HDAC11 was upregulated by GCs (P = 0.028). GC-induced inhibition of Tm histone acetylation alleviated AEII by downregulating IL-4, 5 and 13, similar to the effect of AA.. Histone hyperacetylation status induced by low expression of HDACs 7, 9 and 10 in allergen-specific Tm cells contributes to eosinophilic airway inflammation. The mechanism by which GCs improve airway inflammation involves the upregulation of HDACs 7, 9, 10 and 11 and especially HDAC-10. The role of individual HDACs and AA as novel therapeutic agents for allergic asthma needs to be explored in the future.

Topics: Acetylation; Allergens; Anacardic Acids; Animals; Asthma; Blotting, Western; Bronchoalveolar Lavage Fluid; Cell Culture Techniques; Cytokines; Disease Models, Animal; Eosinophils; Glucocorticoids; Histone Acetyltransferases; Histone Deacetylases; Histones; Hydroxamic Acids; Inflammation; Lung; Male; Mice; Mice, Inbred BALB C; T-Lymphocytes

Group 2 innate lymphoid cells (ILC2) are an important source of the type 2 cytokines interleukin (IL)-5 and IL-13 that are critical to the allergic airway phenotype. Previous studies reported that histone deacetylase (HDAC) inhibition by trichostatin A (TSA) downregulated adaptive allergic immune responses; however, the effect of HDAC inhibition on the early innate allergic immune response is unknown. Therefore, we investigated the effect of TSA on innate airway inflammation mediated by ILC2 activation.. BALB/c mice were challenged intranasally with Alternaria extract, exogenous recombinant mouse IL-33 (rmIL-33) or the respective vehicles for four consecutive days following TSA or vehicle treatment. Bronchoalveolar lavage (BAL) fluids and lungs were harvested 24 h after the last challenge.. We found that TSA treatment significantly decreased the number of ILC2 expressing IL-5 and IL-13 in the lungs challenged with Alternaria extract or rmIL-33 compared with vehicle treatment (p<0.05). TSA treatment significantly decreased protein expression of IL-5, IL-13, CCL11 and CCL24 in the lung homogenates from Alternaria extract-challenged mice or rmIL-33-challenged mice compared with vehicle treatment (p<0.05). Further, TSA treatment significantly decreased the number of perivascular eosinophils and mucus production in the large airways that are critical components of the asthma phenotype (p<0.05). TSA did not change early IL-33 release in the BAL fluids; however, TSA decreased lung IL-33 expression from epithelial cells 24 h after last Alternaria extract challenge compared with vehicle treatment (p<0.05).. These results reveal that TSA reduces allergen-induced ILC2 activation and the early innate immune responses to an inhaled protease-containing aeroallergen.

Topics: Allergens; Alternaria; Animals; Asthma; Bronchoalveolar Lavage; Chemokine CCL11; Chemokine CCL24; Histone Deacetylase Inhibitors; Hydroxamic Acids; Immunity, Innate; Interleukin-13; Interleukin-33; Interleukin-5; Lung; Lymphocytes; Mice; Mice, Inbred BALB C

Histone deacetylase (HDAC) inhibitors may offer novel approaches in the treatment of asthma. We postulate that trichostatin A (TSA), a Class 1 and 2 inhibitor of HDAC, inhibits airway hyperresponsiveness in antigen-challenged mice. Mice were sensitized and challenged with Aspergillus fumigatus antigen (AF) and treated with TSA, dexamethasone, or vehicle. Lung resistance (R(L)) and dynamic compliance were measured, and bronchial alveolar lavage fluid (BALF) was analyzed for numbers of leukocytes and concentrations of cytokines. Human precision-cut lung slices (PCLS) were treated with TSA and their agonist-induced bronchoconstriction was measured, and TSA-treated human airway smooth muscle (ASM) cells were evaluated for the agonist-induced activation of Rho and intracellular release of Ca(2+). The activity of HDAC in murine lungs was enhanced by antigen and abrogated by TSA. TSA also inhibited methacholine (Mch)-induced increases in R(L) and decreases in dynamic compliance in naive control mice and in AF-sensitized and -challenged mice. Total cell counts, concentrations of IL-4, and numbers of eosinophils in BALF were unchanged in mice treated with TSA or vehicle, whereas dexamethasone inhibited the numbers of eosinophils in BALF and concentrations of IL-4. TSA inhibited the carbachol-induced contraction of PCLS. Treatment with TSA inhibited the intracellular release of Ca(2+) in ASM cells in response to histamine, without affecting the activation of Rho. The inhibition of HDAC abrogates airway hyperresponsiveness to Mch in both naive and antigen-challenged mice. TSA inhibits the agonist-induced contraction of PCLS and mobilization of Ca(2+) in ASM cells. Thus, HDAC inhibitors demonstrate a mechanism of action distinct from that of anti-inflammatory agents such as steroids, and represent a promising therapeutic agent for airway disease.

Topics: Animals; Asthma; Blotting, Western; Bronchoalveolar Lavage Fluid; Bronchoconstriction; Calcium; Carbachol; Dexamethasone; Electrophoresis, Polyacrylamide Gel; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Inflammation; Interleukin-4; Interleukin-6; Mice; Mice, Inbred C57BL; Models, Biological

There is a need for new asthma therapies that can concurrently address airway remodeling, airway hyperresponsiveness and progressive irreversible loss of lung function, in addition to inhibiting inflammation. Histone deacetylase inhibitors (HDACi) alter gene expression by interfering with the removal of acetyl groups from histones. The HDACi trichostatin A (TSA) has pleiotropic effects targeting key pathological processes in asthma including inflammation, proliferation, angiogenesis and fibrosis. The aim was to evaluate the effects of TSA treatment in a mouse model of chronic allergic airways disease (AAD). Wild-type BALB/c mice with AAD were treated intraperitoneally with 5 mg/kg TSA or vehicle control. Airway inflammation was assessed by bronchoalveolar lavage fluid (BALF) cell counts and histological examination of lung tissue sections. Remodeling was assessed by morphometric analysis and airway hyperresponsiveness was assessed by invasive plethysmography. TSA-treated mice had a reduced number of total inflammatory cells and eosinophils within the BALF as compared to vehicle-treated mice (both p < 0.05). Furthermore, airway remodeling changes were significantly reduced with TSA compared to vehicle-treated mice, with fewer goblet cells (p < 0.05), less subepithelial collagen deposition (p < 0.05) and attenuated airway hyperresponsiveness at the highest methacholine dose. These findings demonstrate that treatment with an HDACi can concurrently reduce structural airway remodeling changes and airway hyperresponsiveness, in addition to attenuating airway inflammation in a chronic AAD model. This has important implications for the development of novel treatments for severe asthma.

Topics: Airway Remodeling; Animals; Asthma; Bronchial Hyperreactivity; Bronchoalveolar Lavage Fluid; Chronic Disease; Disease Models, Animal; Eosinophils; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung; Mice; Mice, Inbred BALB C

Damage to airway epithelium is followed by deposition of extracellular matrix (ECM) and migration of adjacent epithelial cells. We have shown that epithelial cells from children with asthma fail to heal a wound in vitro.. To determine whether dysregulated ECM production by the epithelium plays a role in aberrant repair in asthma.. Airway epithelial cells (AEC) from children with asthma (n = 36), healthy atopic control subjects (n = 23), and healthy nonatopic control subjects (n = 53) were investigated by microarray, gene expression and silencing, transcript regulation analysis, and ability to close mechanical wounds.. Time to repair a mechanical wound in vitro by AEC from healthy and atopic children was not significantly different and both were faster than AEC from children with asthma. Microarray analysis revealed differential expression of multiple gene sets associated with repair and remodeling in asthmatic AEC. Fibronectin (FN) was the only ECM component whose expression was significantly lower in asthmatic AEC. Expression differences were verified by quantitative polymerase chain reaction and ELISA, and reduced FN expression persisted in asthmatic cells over passage. Silencing of FN expression in nonasthmatic AEC inhibited wound repair, whereas addition of FN to asthmatic AEC restored reparative capacity. Asthmatic AEC failed to synthesize FN in response to wounding or cytokine/growth factor stimulation. Exposure to 5', 2'deoxyazacytidine had no effect on FN expression and subsequent analysis of the FN promoter did not show evidence of DNA methylation.. These data show that the reduced capacity of asthmatic epithelial cells to secrete FN is an important contributor to the dysregulated AEC repair observed in these cells.

Topics: Adolescent; Asthma; Azacitidine; Cells, Cultured; Child; Child, Preschool; Cycloheximide; Dexamethasone; DNA Methylation; Enzyme-Linked Immunosorbent Assay; Epithelial Cells; Extracellular Matrix; Fibronectins; Homocystine; Humans; Hydroxamic Acids; Hypersensitivity; Microarray Analysis; Respiratory Mucosa; Tetradecanoylphorbol Acetate; Transforming Growth Factor beta1

Histone deacetylase (HDAC) inhibition has been demonstrated to change the expression of a restricted set of cellular genes. T cells are essential in the pathogenesis of allergen-induced airway inflammation. It was recently reported that treatment with HDAC inhibitors induces a T cell-suppressive effect.. The purpose of this study was to determine whether treatment with trichostatin A (TSA), a representative HDAC inhibitor, would reduce allergen-induced airway inflammation in a mouse asthma model.. BALB/c mice were intraperitoneally sensitized to ovalbumin (OVA) and challenged with an aerosol of OVA. TSA (1 mg/kg body weight) was injected intraperitoneally every 2 days beginning on day 1. Mouse lungs were assayed immunohistochemically for HDAC1, a major HDAC subtype, and for infiltration of CD4+ cells. The effect of TSA on airway hyper-responsiveness (AHR) was determined, and the bronchoalveolar lavage fluid (BALF) of these mice was assayed for the number and types of inflammatory cells, and for the concentrations of IL-4, IL-5, and IgE.. HDAC1 was localized within most airway cells and infiltrating inflammatory cells of asthmatic lungs. Treatment with TSA significantly attenuated AHR, as well as the numbers of eosinophils and lymphocytes in BALF. TSA also reduced infiltration of CD4+ and inflammatory cells and mucus occlusions in lung tissue, and decreased the concentrations of IL-4, IL-5, and IgE in BALF.. TSA attenuated the development of allergic airway inflammation by decreasing expression of the Th2 cytokines, IL-4 and IL-5, and IgE, which resulted from reduced T cell infiltration. Our results suggest that HDAC inhibition may attenuate the development of asthma by a T cell suppressive effect.

Topics: Animals; Asthma; Bronchoalveolar Lavage Fluid; Female; Histone Deacetylase Inhibitors; Hydroxamic Acids; Immunoglobulin E; Immunohistochemistry; Interleukin-4; Interleukin-5; Leukocyte Count; Lung; Mice; Mice, Inbred BALB C; Models, Animal; Ovalbumin