Project description:Activated macrophages have been implicated in lung injury and fibrosis induced by the cytotoxic alkylating agent, nitrogen mustard (NM). Herein, we determined if macrophage activation is associated with altered miRNA expression. Treatment of rats with NM (0.125 mg/kg, i.t.) resulted in significant increases in miRNA expression 1, 3, 7, and 28 d post exposure as determined by PCR array analysis of miRNAs (miR)s involved in inflammation and fibrosis. Expression of many miRNAs were significantly increased at multiple time-points while one miRNA was uniquely expressed 1 d post-NM, one at 3 d, two at 7 d, and five at 28 d. An IPA Core Analysis of predicted mRNA targets of differentially expressed miRNAs identified significant enrichment of Diseases and Functions related to cell cycle arrest, apoptosis, cell movement, cell adhesion, and inflammation 1 d and 28 d post NM. Significant enrichment of pathways related to lipid metabolism is consistent with previous studies reporting the development of macrophage foam cells after NM exposure. miRNA-mRNA interaction network analysis identified highly connected miRNAs representing key upstream regulators of mRNAs involved in significantly enriched Diseases and Functions including miR-34c-5p and miR-27a-3p at 1 d post NM and miR-125b-5p, miR-16-5p, miR-30c-5p, miR-19b-3p, and miR-148b-3p at 28 d post NM. Collectively, these data show that NM promotes histone remodeling and alterations in miRNA expression linked to lung macrophage responses during inflammatory injury and fibrosis.
Project description:Sulfur mustard (SM) is a potent vesicant that targets epithelial cells and tissues. Most vesicant research has been performed using bona fide SM; however, some studies have used simulants, most notably half mustard (2-chloroethyl ethylsulfide; CEES) and nitrogen mustard (mechlorethamine; NM). Although CEES and NM have similarities to SM and can cause vesication, there are distinct differences in the chemical structures and physical properties of these compounds that may impact their toxic effects. Microarray analysis of cultured primary human epidermal keratinocytes (HEK) exposed to each of these vesicants was performed to directly compare the transcriptional responses induced by these vesicants. HEK were exposed in triplicate to concentrations ranging from 0-1000 µM for SM and NM and 0-4000 µM for CEES. Cells were harvested at 1, 2, 4, 8, 16, and 24 h and the RNA isolated for microarray analysis. Transcriptional responses were phenotypically anchored to cell morphology. The dataset was filtered by exposure and timepoint, and an analysis of variance was performed using dose as the factor. The top 500 genes ranked by p-value were analyzed using gene ontology algorithms to identify biological pathways significantly affected by each vesicant. At 2 h post-exposure, p53 signaling, Erk/MAPK signaling, and BMP signaling were significantly affected by all three vesicants. At 4 h post-exposure, p53 signaling , B cell activating factor, and glucocorticoid receptor signaling were significantly affected by all three vesicants. At 8 h post-exposure, there were no significant pathways commonly affected by all three vesicants. These results suggest that, although there are similarities in the transcriptional responses to each of these vesicants, the transcriptional responses appear to differ over time. Thus, extrapolation of results obtained with one vesicant to other vesicants may be complex and may have important implications for the development of vesicant therapeutics.
Project description:The bifunctional alkylating agent sulfur mustard (SM; bis-(2-dichloroethyl) sulfide) is a potent vesicating chemical that has previously been used as a chemical warfare agent. studies have shown that exposure to CWNA compounds induces damage in the brain and heart.
Project description:Nitrogen mustard (NM) is a vesicant known to target the lung, causing acute injury which progresses to fibrosis. Evidence suggests that activated macrophages contribute to the pathologic response to NM. In these studies, we analyzed the role of lung lipids generated following NM exposure on macrophage activation and phenotype. Treatment of rats with NM (0.125 mg/kg, i.t.) resulted in a time-related increase in enlarged vacuolated macrophages in the lung. At 28 d post exposure, macrophages stained positively for Oil Red O, a marker of neutral lipids. This was correlated with an accumulation of oxidized phospholipids in lung macrophages and epithelial cells, and an increase in bronchoalveolar lavage fluid (BAL) phospholipids. RNA-sequencing analysis revealed that lipid handling pathways under control of the transcription factors LXR, FXR and PPAR-ɣ were significantly altered following NM exposure. Whereas at 1-3 d post NM, FXR and the downstream oxidized low density lipoprotein receptor, Cd36, were increased, Lxr and the lipid extrusion pump targets, Abca1 and Abcg1 were reduced. Treatment of naïve lung macrophages with lipid enriched fractions of BAL collected 3 d after NM resulted in upregulation of Nos2, Apoe and Ptgs2, markers of pro-inflammatory activation, while lipid-enriched BAL collected 28 d post NM upregulated expression of the anti-inflammatory markers, Il10, Cd163, and Cx3cr1, and induced the formation of lipid-laden foamy macrophages. These data suggest that NM-induced alterations in lipid handling and metabolism drive macrophage foam cell formation, potentially contributing to the development of pulmonary fibrosis.
Project description:Sulfur mustard (SM) is a potent alkylating agent. We are developing medical countermeasures to reduce the injury caused by SM exposure. Screening in the mouse ear vesicant model has identified three effective compounds: dimercaprol (British anti-lewisite), indomethacin, and octyl homovanillamide (OHV). To identify gene expression changes that correlate with compound efficacy we used oligonucleotide microarrays to compare gene expression profiles in vehicle-exposed skin, SM-exposed skin, and skin pretreated with each compound before SM exposure. Mice were topically exposed on the inner surface of the right ear to SM alone or pretreated for 15 min with one of the compounds and then exposed to SM. Left ears were vehicle-exposed. Ear tissue was harvested 24 hr later for ear weight determination (an endpoint indicating compound efficacy). The exposure groups were: methylene chloride (sulfur mustard vehicle); ethanol (drug vehicle); 0.08 mg sulfur mustard; 6.25 mg dimercaprol 15 min before 0.08 mg sulfur mustard; 1.34 mg indomethacin 15 min before 0.08 mg sulfur mustard; 0.6 mg octylhomovanillamide 15 min before 0.08 mg sulfur mustard; 6.25 mg dimercaprol alone; 1.34 mg indomethacin alone; 0.6 mg octylhomovanillamide alone. RNA was extracted from the tissues and used to generate oligonucleotide microarray probes. Principal component analysis of the gene expression data revealed partitioning of the samples based on drug treatment and SM exposure. Vehicle-exposed mouse ears clustered away from the other treatment groups. SM-exposed mouse ears pretreated with dimercaprol or OHV clustered more closely with vehicle-exposed ears, while SM-exposed mouse ears pretreated with indomethacin clustered more closely with SM-exposed ears. This clustering of the samples is supported by the ear weight data, in which the indomethacin group has ear weights closer to the SM-exposed group, whereas the dimercaprol and OHV groups have ear weights closer to the vehicle-exposed group. Correlation coefficients were calculated for each gene based on the correlation between gene expression level and ear weight. These data provide the basis for understanding what gene expression changes are important in the development of effective SM medical countermeasures. Experiment Overall Design: Exposure of mouse ears to sulfur mustard alone, sulfur mustard preceded by drug treatment, or vehicle compounds. Naive controls were also included. Biological replicates of at least n=3 were examined for each exposure condition.
Project description:Sulfur mustard is a vesicant chemical warfare agent, which has been used during Iraq-Iran-war. Many veterans and civilians still suffer from long-term complications of sulfur mustard exposure, especially in their lung. Although the lung lesions of these patients are similar to Chronic Obstructive Pulmonary Disease (COPD), there are some differences due to different etiology and clinical care. Less is known on the molecular mechanism of sulfur mustard patients and specific treatment options. microRNAs are master regulators of many biological pathways and proofed to be stable surrogate markers in body fluids. Based on that microRNA expression for serum samples of sulfur mustard patients were examined, to establish specific microRNA patterns as a basis for diagnostic use and insight into affected molecular pathways. Patients were categorized based on their long-term complications into three groups and microRNA serum levels were measured. The differentially regulated microRNAs and their corresponding gene targets were identified. Cell cycle arrest, ageing and TGF-beta signaling pathways showed up to be the most deregulated pathways. The candidate microRNA miR-143-3p could be validated on all individual patients. In a ROC analysis miR-143-3p turned out to be a suitable diagnostic biomarker in the mild and severe categories of patients. Further microRNAs which might own a link to the biology of the sulfur mustard patients are miR-365a-3p, miR-200a-3p, miR-663a. miR-148a-3p, which showed up only in a validation study, might be linked to the airway complications of the sulfur mustard patients. All the other candidate microRNAs do not directly link to COPD phenotype or lung complications. In summary the microRNA screening study characterizes several molecular difference in-between the clinical categories of the sulfur mustard exposure groups and established some useful microRNA biomarkers.
Project description:Sulfur mustard (SM) is a hazardous chemical warfare agent. Exposure to SM results in various pathologies including skin lesions and impaired wound healing. To date, there are no effective treatments available. Here we discover that the miRNA miR-497-5p is induced in epidermal cells by SM and mediates keratinocyte dysfunction. Transcriptome analysis using RNA-seq in normal human epidermal keratinocytes (NHEK) revealed that SM evoked differential expression of 1,896 mRNAs and 25 miRNAs with many of these RNAs known to be involved in keratinocyte function and wound healing. We demonstrated that keratinocyte differentiation and proliferation were efficiently regulated by miRNAs induced in skin cells after exposure to SM. The inhibition of miR-497-5p counteracted SM-induced premature differentiation and inhibition of proliferation in NHEK. In addition, we showed that microneedle-mediated transdermal application of lipid-nanoparticles containing miR-497-5p inhibitor improved the healing of human skin biopsies upon exposure to SM. Our findings expand the current understanding of SM-associated molecular toxicology in keratinocytes and highlight miR-497-5p as feasible clinical target for specific skin therapy in SM-exposed patients and beyond.
Project description:To establish an expression profile of Nitrogen Mustard (NM) exposure-induced genes in healthy human skin and effect of VitD intervention. We further characterized a distinct intervention-independent response type in half of subjects after the 2nd NM exposure
Project description:Normal human epidermal keratinocytes (NHEKs) and HaCaTs have been widely used as cell culture models to study the effects of cutaneous sulfur mustard (HD) exposure. While these cell lines are similar, one key difference is that NHEKs are primary cells, whereas HaCaT cells are a transformed line with a mutation in the p53 gene. However, the impact of this mutation on the response of HaCaT cells to HD is unclear. Thus, gene expression profiling was performed to compare the transcriptional responses of NHEKs and HaCaTs after HD exposure. Cells were exposed to 0, 25, and 200 µM HD, harvested at 1 h and 8 h post-exposure, and processed for microarray analysis. Principal component analysis of the microarray data suggested profile differences based on cell type, but both cell types respond similarly to HD with regard to dose and time. To further analyze the expression profiles at various doses, the dataset was filtered by dose, and an analysis of variance was performed using cell type as the factor; the pathways most significantly different between these cell types were identified. At all three doses, the p53 and N-glycan degradation pathways were significantly different between NHEKs and HaCaTs. Interestingly, p53 responsive genes showed differences and similarities across cell types, which may provide insight into the role of p53 in HD toxicity. The inflammatory pathways expected to respond to HD exposure were not significantly different between cell types, suggesting that both NHEKs and HaCaTs are appropriate models to study the inflammatory effects of HD.