This proposal seeks to provide the opportunity for the Principal Investigator (PI) to gain knowledge and skills in molecular biology and genetic epidemiology, under the direct supervision of a highly qualified sponsor, in order to enhance his potential to develop into an independent investigator. The PI is trained in Pediatric Pulmonary Medicine and has recently completed three years research in the cell biology of airway smooth muscle. The first two years of this proposal will incorporate the necessary course-work, seminars, and hands-on experience in new molecular biology and genetic techniques to enable to PI to complete and intensive research experience over the full five years of the proposal. The overall scientific goal of this proposal is to establish the associations between beta2-adrenergic receptor (beta2-AR) polymorphisms and desensitization and to understand the mechanism by which they occur. Because airway smooth muscle is the ultimate and primary target of beta-agonist therapy, cultured human airway smooth muscle (HASM) cell will be used. The hypothesis is that beta2-AR polymorphisms influence acute and long-term desensitization by altering basal cell-surface beta2-AR density, and this will be evaluated by 4 specific aims: First, beta2-AR density, cell stiffness, and cAMP formation will be studied at baseline and in response to Isoproterenol (Iso) in HASM cells exposed to Iso short-and long-term, and the data will be stratified by beta2-AR genotype. Second, heterologous desensitization will be evaluated in a similar manner by pretreating HASM cells with PGE2, IL-1beta, or dibutyryl cAMP (db-cAMP). Third, given the proposed mechanisms by which beta2-AR polymorphisms increase desensitization, dexamethasone (Dex) will be expected to increase beta2-AR density and inhibit desensitization only in those polymorphisms where baseline beta2-AR density is low. Fourth, to study the effects of polymorphisms in the 5'-flanking region on transcription of the beta2-AR gene in HASM cells, transient transfection analysis using luciferase-promoter reporter constructs, which include this 5'-flanking region, will be performed at baseline and in cells pretreated with db-cAMP or Dex. Defining the beta2-AR genotypes that alter beta-agonist responses may thus have significant therapeutic consequences on the use of beta-agonists.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Clinical Investigator Award (CIA) (K08)
Project #
7K08HL004395-02
Application #
6500305
Study Section
Special Emphasis Panel (ZHL1-CSR-K (M1))
Program Officer
Rothgeb, Ann E
Project Start
2000-07-10
Project End
2005-06-30
Budget Start
2001-07-01
Budget End
2002-06-30
Support Year
2
Fiscal Year
2001
Total Cost
$124,443
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Pediatrics
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
Moore, Paul E; Williams, Scott M; Gebretsadik, Tebeb et al. (2008) beta(2)-adrenergic receptor promoter haplotype influences spirometric response during an acute asthma exacerbation. Clin Transl Sci 1:155-61
Moore, Paul E; Cunningham, Gary; Calder, Mark M et al. (2006) Respiratory syncytial virus infection reduces beta2-adrenergic responses in human airway smooth muscle. Am J Respir Cell Mol Biol 35:559-64
Faffe, Debora S; Flynt, Lesley; Mellema, Matthew et al. (2005) Oncostatin M causes eotaxin-1 release from airway smooth muscle: synergy with IL-4 and IL-13. J Allergy Clin Immunol 115:514-20
Baraldo, Simonetta; Faffe, Deborah S; Moore, Paul E et al. (2003) Interleukin-9 influences chemokine release in airway smooth muscle: role of ERK. Am J Physiol Lung Cell Mol Physiol 284:L1093-102
Moore, Paul E; Calder, Mark M; Silverman, Eric S et al. (2003) Effect of dexamethasone on beta2-adrenergic desensitization in airway smooth muscle: role of the ARG19 polymorphism. Chest 123:368S-9S
Shore, Stephanie A; Moore, Paul E (2002) Effects of cytokines on contractile and dilator responses of airway smooth muscle. Clin Exp Pharmacol Physiol 29:859-66
Lahiri, Thomas; Moore, Paul E; Baraldo, Simonetta et al. (2002) Effect of IL-1beta on CRE-dependent gene expression in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 283:L1239-46
Moore, Paul E; Church, Trudi L; Chism, David D et al. (2002) IL-13 and IL-4 cause eotaxin release in human airway smooth muscle cells: a role for ERK. Am J Physiol Lung Cell Mol Physiol 282:L847-53
Moore, P E; Lahiri, T; Laporte, J D et al. (2001) Selected contribution: synergism between TNF-alpha and IL-1 beta in airway smooth muscle cells: implications for beta-adrenergic responsiveness. J Appl Physiol 91:1467-74