Airway inflammation plays a critical role in the pathogenesis of chronic asthma. Glucocorticoid (GC)s are the cornerstone of anti-inflammatory therapy in this disease. However, not all asthmatics improve their pulmonary function following GC therapy. These patients are subjected to the unwanted side effects of prolonged systemic GC therapy, often in situations where there is no evidence that it is exerting any appreciable benefit. Recent analyses of the economic burden of asthma suggest that the costs of asthma are largely attributable to uncontrolled disease. Although patients with severe asthma represent a minority of asthmatics, they account for much of the morbidity and cost of the disease due to use of costly medications, emergency room visits and frequent hospitalizations. We have recently found that peripheral blood monocytes and BAL macrophages of corticosteroid-resistant asthmatics have increased baseline levels of phospho-p38 mitogen-activated protein kinase (p-p38 MAPK) activation in their monocyte/macrophages. The current proposal will examine the mechanisms underlying increased p-p38 MAPK and its role in posttranslational modifications of GCR alpha function in CR asthma. We hypothesize that p38 activation results in corticosteroid resistance by interfering with GCR alpha nuclear translocation required for optimal transactivation and transrepression. Preliminary data indicates that loss of asthma control is associated with the expansion of unique organisms not seen in the normal microbiome.
Our specific aims will be: 1) to determine the role of p-p38 MAPK in monocyte/macrophage corticosteroid insensitivity; 2) to characterize the microbiome in asthmatics with persistent airway obstruction to determine the potential trigger for cell p38 activation in CR asthma; 3) to determine whether the clinical steroid sparing effects of vitamin D result from its ability to induce mitogen activated kinase phosphatase-1 (MKP-1), a critical phosphatase that downregulates p38 activation in monocytes/macrophages; 4) to examine the mechanisms leading to reduced half-life of MKP-1 in CR asthmatics. The elucidation of mechanisms underlying steroid resistance will have important consequences for development of biomarkers to diagnose and monitor steroid resistance, as well as develop novel therapeutic modalities in the treatment of CR asthma as well as other chronic inflammatory conditions where altered GC responsiveness contributes to persistent tissue inflammation.
Corticosteroids are the most common anti-inflammatory therapy used in the treatment of persistent asthma. However some asthmatics fail to respond to steroid therapy. The current study will study mechanisms and microbiome underlying steroid unresponsiveness. Data from such studies will provide valuable insights into the development of new treatments for control of airway inflammation in persistent asthma.
|Goleva, Elena; Covar, Ronina; Martin, Richard J et al. (2016) Corticosteroid pharmacokinetic abnormalities in overweight and obese corticosteroid resistant asthmatics. J Allergy Clin Immunol Pract 4:357-60.e2|
|Li, Ling-Bo; Leung, Donald Y M; Goleva, Elena (2015) Activated p38 MAPK in Peripheral Blood Monocytes of Steroid Resistant Asthmatics. PLoS One 10:e0141909|
|Zhang, Yong; Leung, Donald Y M; Goleva, Elena (2014) Anti-inflammatory and corticosteroid-enhancing actions of vitamin D in monocytes of patients with steroid-resistant and those with steroid-sensitive asthma. J Allergy Clin Immunol 133:1744-52.e1|
|Goleva, Elena; Jackson, Leisa P; Harris, J Kirk et al. (2013) The effects of airway microbiome on corticosteroid responsiveness in asthma. Am J Respir Crit Care Med 188:1193-201|
|Dakhama, A; Collins, M L; Ohnishi, H et al. (2013) IL-13-producing BLT1-positive CD8 cells are increased in asthma and are associated with airway obstruction. Allergy 68:666-73|
|Zhang, Yong; Leung, Donald Y M; Goleva, Elena (2013) Vitamin D enhances glucocorticoid action in human monocytes: involvement of granulocyte-macrophage colony-stimulating factor and mediator complex subunit 14. J Biol Chem 288:14544-53|
|Goleva, Elena; Searing, Daniel A; Jackson, Leisa P et al. (2012) Steroid requirements and immune associations with vitamin D are stronger in children than adults with asthma. J Allergy Clin Immunol 129:1243-51|
|Goleva, Elena; Jackson, Leisa P; Gleason, Melanie et al. (2012) Usefulness of PBMCs to predict clinical response to corticosteroids in asthmatic patients. J Allergy Clin Immunol 129:687-693.e1|
|Sutherland, E Rand; Goleva, Elena; King, Tonya S et al. (2012) Cluster analysis of obesity and asthma phenotypes. PLoS One 7:e36631|
|Zhang, Yong; Leung, Donald Y M; Richers, Brittany N et al. (2012) Vitamin D inhibits monocyte/macrophage proinflammatory cytokine production by targeting MAPK phosphatase-1. J Immunol 188:2127-35|
Showing the most recent 10 out of 14 publications