Investigating the CDC42 pathway as a novel pathway for pediatric non-atopic obesity-related asthma

研究 CDC42 通路作为儿童非特应性肥胖相关哮喘的新通路

• 批准号: 10220121
• 负责人: Deepa Rastogi
• 金额: $ 48.67万
• 依托单位: CHILDREN'S RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10220121
• 关键词: Affect; Albuterol; Asthma; Attenuated; Awareness; Biochemical; Biology; Bronchoalveolar Lavage; CD4 Positive T Lymphocytes; CXCL10 gene; Cell Cycle; Cell physiology; Cells; Child; Childhood; Childhood Asthma; Chronic Disease; Clinical; Cytokine Suppression; Data; Dexamethasone; Drug Targeting; Extrinsic asthma; Flow Cytometry; Gene Expression; Genes; Genotype; Helper-Inducer T-Lymphocyte; Heterogeneity; Immune; Immune response; Immunobiology; In Vitro; Inflammation; Inhalation; Interferon Type II; Interleukin-6; Light; Link; MAPK8 gene; Measures; Mediating; Memory; Metabolic; Monomeric GTP-Binding Proteins; Non obese; Obesity; Pathway interactions; Pharmaceutical Preparations; Phenotype; Play; Proteins; Reporting; Research; Resistance; Risk; Role; Screening procedure; Signal Pathway; Small Interfering RNA; Steroid Resistance; Steroids; Subgroup; T-Lymphocyte; TNF gene; Testing; Th2 Cells; Transcript; Treatment Failure; Up-Regulation; VAV2 gene; Weight; airway obstruction; asthmatic; asthmatic airway; base; burden of illness; cell type; cohort; cytokine; drug discovery; insight; mTOR Signaling Pathway; new therapeutic target; novel; obesity in children; obesity treatment; p38 Mitogen Activated Protein Kinase; peripheral blood; predictive signature; promoter; public health relevance; pulmonary function; response; single-cell RNA sequencing; targeted treatment; transcriptome sequencing

ABSTRACT Non-atopic or Th2-low asthma is now recognized as a major subgroup of pediatric asthma. Obesity-related asthma, the most commonly reported form of pediatric non-atopic asthma, is associated with high disease burden, worse lung function, and lack of response/resistance to medications. Thus, there is an urgent need to investigate the immunobiology of non-atopic asthma to identify novel therapeutic targets. We and others have previously reported non-atopic immune responses in peripheral blood from obese asthmatic children, with elevated TH1/ TH2 ratio and increased TNF, IL-6, IFNγ, and IP-10 that correlated with pulmonary function deficits in obesity-related asthma. Using RNA-Seq, we probed the biology of non-atopic responses in un- stimulated obese asthmatic CD4+ (TH) cells and found upregulation of several genes (DOCK5, VAV2, CDC42EP4, PAK3, MLK3 and PLD1) in the Cell Division Cycle 42 (CDC42) pathway. Higher CDC42EP4 and DOCK5 gene expression correlated with worse airway obstruction in obese asthmatic children. Phosphorylated p38, downstream of MLK3, and linked with steroid resistance in asthma, was higher in stimulated obese asthmatic TH cells. Small interfering RNA (siRNA)-mediated CDC42 silencing in TH cells led to lower IFNγ and TNF, but not IL-4, gene expression. Together, these results suggest a novel role for the CDC42 pathway in non-atopic inflammation in obesity-related asthma. Based on these observations, we hypothesize that in obese asthmatics, upregulation of the CDC42 pathway in a non-TH2 TH cell, which is enriched in the airway, and activation of CDC42-regulated signaling pathways, contribute to steroid resistance and disease burden. To test our hypothesis, we will identify the non-TH2 TH cell with CDC42 pathway upregulation and quantify activation of CDC42-regulated signaling pathways in obese asthmatics. We will investigate enrichment of the non-TH2 TH cell in peripheral blood in 50 non-atopic obese asthmatics as compared to 50 non-atopic normal-weight asthmatics, 50 obese non-asthmatics, and 50 healthy controls. Enrichment of the non-TH2 TH cell in the airway will be investigated in a subset of 20 obese asthmatics and compared to 20 normal-weight asthmatics. Absent or attenuated cytokine suppression in the non-TH2 TH cell in response to dexamethasone will provide evidence that the cell is steroid resistant and gain of steroid sensitivity following CDC42 and/or CDC42-regulated signaling pathway inhibition will support a role of CDC42 in steroid resistance in non-atopic asthma. To identify the contribution of obesity, and of factors other than obesity, we will compare the findings in non-atopic obese asthmatics to obese non-asthmatics. Lastly, to link CDC42 activation with disease burden, we will identify a biochemical signature predictive of CDC42 activation, and investigate its contribution to disease burden in pediatric non-atopic obesity-related asthma. These studies will confirm a role of CDC42 pathway in the immunobiology and disease burden of non-atopic asthma, and will identify the non- TH2 TH cell and/or proteins in the signaling pathways as novel therapeutic targets for obesity-related asthma.

摘要 非特应性或Th2低哮喘现在被认为是儿童哮喘的一个主要亚型。与肥胖相关 哮喘是儿科非特应性哮喘中最常见的一种，与高度疾病有关。 负担重，肺功能较差，对药物缺乏反应/抵抗力。因此，迫切需要 研究非特应性哮喘的免疫生物学，以确定新的治疗靶点。我们和其他人有 先前报道了肥胖哮喘儿童外周血中的非特应性免疫反应， Th1/Th2比值升高及与肺功能相关的肿瘤坏死因子、IL-6、干扰素γ和IP-10升高 肥胖相关哮喘的缺陷。利用RNA-Seq技术，我们探索了非特应性反应的生物学机制。 刺激肥胖哮喘CD4+(TH)细胞，发现几个基因(DOCK5，VAV2， CDC42EP4、PAK3、MLK3和PLD1)参与了细胞分裂周期42(CDC42)途径。更高的CDC42EP4和 Dock5基因的表达与肥胖哮喘儿童的气道阻塞程度相关。磷酸化 P38位于MLK3下游，在哮喘中与类固醇抵抗有关，在刺激性肥胖中表达较高。 哮喘患者的TH细胞。小干扰核糖核酸介导的CDC42沉默TH细胞导致干扰素γ和 肿瘤坏死因子，而不是IL-4的基因表达。综上所述，这些结果提示了cdc42途径在 肥胖相关哮喘的非特应性炎症。基于这些观察，我们假设在 肥胖哮喘患者，非TH2 TH细胞中CDC42途径上调，该细胞富含 呼吸道，并激活CDC42调节的信号通路，有助于类固醇抵抗和 疾病负担。为了验证我们的假设，我们将鉴定具有CDC42途径上调的非TH2 TH细胞 并量化肥胖哮喘患者中CDC42调节的信号通路的激活。我们会调查的 50例非特应性肥胖性哮喘患者外周血中非TH2细胞的浓缩 非特应性正常体重哮喘患者50例，肥胖非哮喘患者50例，健康对照组50例。浓缩物 将在20名肥胖哮喘患者中对呼吸道中的非TH2细胞进行研究，并与20名 体重正常的哮喘患者。非TH2细胞中缺乏或减弱的细胞因子抑制 地塞米松将提供证据，证明细胞对类固醇耐药，并在以下情况下获得类固醇敏感性 CDC42和/或CDC42调节的信号通路抑制将支持CDC42在类固醇耐药中的作用 在非特应性哮喘中。为了确定肥胖的贡献，以及肥胖以外的其他因素，我们将比较 非特应性肥胖哮喘患者与肥胖非哮喘患者的研究结果。最后，要将CDC42的激活与 疾病负担，我们将确定一个预测CDC42激活的生化特征，并研究其 儿童非特应性肥胖相关哮喘对疾病负担的贡献。这些研究将确认一个角色 研究CDC42通路在非特应性哮喘免疫生物学和疾病负担中的作用，并将识别非特应性哮喘 Th2细胞和/或信号通路中的蛋白质作为肥胖相关哮喘的新治疗靶点。