Project description:Rationale: Augmented smooth muscle contractility of the airways is one of the causes of airway hyperresponsiveness in asthmatics. However, the mechanism of the altered properties of airway smooth muscle cells is not well understood. Objectives: To identify differentially expressed genes (DEGs) related to the bronchial smooth muscle (BSM) hyper-contractility in a murine asthma model. Methods: The ovalbumin (OA)-sensitized mice were repeatedly challenged with aerosolized OA to induce asthmatic reaction. Transcriptomic profiles were generated by microarray analysis of BSMs from the OA-challenged and control animals, and KEGG (Kyoto Encyclopedia of Genes and Genomes) Pathway Analysis was applied. Measurements and Main Results: Tension study showed a BSM hyperresponsiveness to acetylcholine (ACh) in the OA-challenged mice. A total of 770 genes were differentially expressed between the OA-challenged and control animals. Pathway analysis showed a significant change in arachidonic acid (AA) metabolism pathway in BSMs of the OA-challenged mice. Validation of DEGs by quantitative RT-PCR showed a significant increase in PLA2 group 4c (Pla2g4c)/COX-2 (Ptgs2)/PGD2 synthase 2 (Hpgds) axis. PGD2 level in bronchoalveolar fluids of the OA-challenged mice was significantly increased. A 24-h incubation of BSMs with PGD2 caused a hyperresponsiveness to ACh in naive control mice. Conclusions: AA metabolism is shifted towards PGD2 production in BSMs of asthma. Increased PGD2 level in the airways might be a cause of the BSM hyperresponsiveness in asthma.
Project description:RationaleAugmented smooth muscle contractility of the airways is one of the causes of airway hyperresponsiveness in asthmatics. However, the mechanism of the altered properties of airway smooth muscle cells is not well understood.ObjectivesTo identify differentially expressed genes (DEGs) related to the bronchial smooth muscle (BSM) hyper-contractility in a murine asthma model.MethodsThe ovalbumin (OA)-sensitized mice were repeatedly challenged with aerosolized OA to induce asthmatic reaction. Transcriptomic profiles were generated by microarray analysis of BSM tissues from the OA-challenged and control animals, and KEGG (Kyoto Encyclopedia of Genes and Genomes) Pathway Analysis was applied.Measurements and main resultsTension study showed a BSM hyperresponsiveness to acetylcholine (ACh) in the OA-challenged mice. A total of 770 genes were differentially expressed between the OA-challenged and control animals. Pathway analysis showed a significant change in arachidonic acid (AA) metabolism pathway in BSM tissues of the OA-challenged mice. Validation of DEGs by quantitative RT-PCR showed a significant increase in PLA2 group 4c (Pla2g4c)/COX-2 (Ptgs2)/PGD2 synthase 2 (Hpgds) axis. PGD2 level in bronchoalveolar fluids of the OA-challenged mice was significantly increased. A 24-h incubation of BSM tissues with PGD2 caused a hyperresponsiveness to ACh in naive control mice.ConclusionsAA metabolism is shifted towards PGD2 production in BSM tissues of asthma. Increased PGD2 level in the airways might be a cause of the BSM hyperresponsiveness in asthma.
Project description:Transcriptional profiling of lung bronchial biospsy mRNA from asthmatics Two-condition experiment, mRNA from asthma bronchial biopsies for test channel and Stratagene Universal Human Reference RNA for reference channel.
Project description:Asthma is a complex syndrome associated with episodic decompensations provoked by aeroaller-gen exposures. The underlying pathophysiological states driving exacerbations are latent in the resting state and do not adequately inform biomarker-driven therapy. A better understanding of the pathophysiological pathways driving allergic exacerbations is needed. We hypothesized that disease-associated pathways could be identified in humans by unbiased metabolomics of bron-choalveolar fluid (BALF) during the peak inflammatory response provoked by a bronchial aller-gen challenge. We analyzed BALF metabolites in samples from 12 volunteers who underwent segmental bronchial antigen provocation (SBP-Ag). Metabolites were quantified using liquid chromatography-tandem mass spectrometry (LC–MS/MS) followed by pathway analysis and cor-relation with airway inflammation. SBP-Ag induced statistically significant changes in 549 fea-tures that mapped to 72 uniquely identified metabolites. From these features, two distinct induci-ble metabolic phenotypes were identified by the principal component analysis, partitioning around medoids (PAM) and k-means clustering. Ten index metabolites were identified that in-formed the presence of asthma-relevant pathways, including unsaturated fatty acid produc-tion/metabolism, mitochondrial beta oxidation of unsaturated fatty acid, and bile acid metabolism. Pathways were validated using proteomics in eosinophils. A segmental bronchial allergen chal-lenge induces distinct metabolic responses in humans, providing insight into pathogenic and pro-tective endotypes in allergic asthma.
Project description:Biological mechanisms explaining asthma control improvement following bronchial thermoplasty are still not well understood. We used a large-scale transcriptomic approach to evaluate the transcriptome of bronchial epithelial cell (BEC) obtained before and after bronchial thermoplasty treatment (BT).
Project description:Bronchial thermoplasty (BT) is an endoscopic therapy employed for the treatment of refractory asthma. However, no predictive factors are available that determine the effectiveness of BT in treating asthma patients. The present study aimed to comprehensively analyze RNA samples from the airway bronchial tissues of 8 patients with severe asthma treated by BT, and to characterize each patient as a BT responder or non-responder. Total 24 RNA samples (three per patient prior to BT1 [baseline], prior to BT2 [after 1st time treatment], and prior to BT3 [after 2nd time treatment]) were obtained. There were 975 differentially expressed (DE) genes in the bronchial tissues of 8 patients between prior to BT1 (baseline) and prior to BT2 (after 1st time treatment), with significant differences (FDR-adjusted P<0.05). Subjects with an Asthma Quality of Life Questionnaire score change of >0.5 for a period of 12 months were considered BT responders. Non-responders exhibited a score change of <0.5 for 12 months. Transcriptome analysis at baseline identified 67 genes that were differentially expressed between responders and non-responders, including SLPI, MMP3, and MUC19 which were upregulated in responders.
Project description:In this study we explore the underlying differences in bronchial epithelial cells from asthma patinets compared to healthy controls. In addition we also explore the differential gene expression of severe asthma patients compared to mild and moderate asthma patients to determine if there are genes that lead to severity of the disease
Project description:Asthma pathogenesis and susceptibility involves a complex interplay between genetic and environmental factors. We report the results of expression microarray studies using tissue obtained from bronchial biopsies of healthy controls and of subjects with allergic asthma, both before and following inhaled corticotherapy.
Project description:Bronchial epithelial brushings were obtained by bronchoscopy from 8 steroid-naïve asthmatics including type 2-low (n=4) and type 2-high asthma (n=4), and 4 healthy controls. The type 2-low and –high asthma was defined by the epithelial expression of a three-gene signature for type 2 status (POSTN, SERPINB2, and CLCA1).
Project description:Human Rhinovirus (HRV) infection can trigger exacerbations of asthma. Understanding of the mechanisms provoking airway inflammation and remodeling in asthma, as well as the pathogenic mechanisms of HRV infection and its association with asthma exacerbations, may offer significant opportunities for improved disease management. Genome-wide expression analysis of HRV type 1A-infected primary bronchial epithelial (PBE) cells from normal and asthmatic donors was performed to determine whether asthma is associated with a unique pattern of gene expression after HRV infection in vitro. Keywords: response to rhinovirus infection