Our long range goal remains performing experiments that help elucidate the regulation of alveolar turnover (formation and loss) in the hope this information might be therapeutically useful. Our past, and proposed, work are most relevant to bronchopulmonary dysplasia (BPD), a condition of very prematurely born infants in which arrested alveolarization is a key feature, and chronic obstructive pulmonary disease (COPD), in which alveolar destruction causes substantial morbidity and mortality. There is no remediation for the relentlessly progressive alveolar destruction of COPD, to which increasing evidence suggests women are more susceptible than men, and in whom the downhill course is more rapid. Key new findings since the last submission are: 1. Adult female estrogen receptor (ER)alpha and ERbeta k.o. mice have an alveolar phenotype - larger and fewer alveoli with less surface area than wildtype mice. 2. Ovariectomy in adult mice results, within 3 weeks, in a loss of 45% of alveoli and 13% of alveolar surface area. 3. Estrogen replacement, after alveolar loss has occurred, rescues the loss. 4. As proof of principle, we show in adult mice a) nasal instillation of microliter (fl) amounts of elastase in surfactant (SAM) resulted in severe diffuse emphysema thereby demonstrating diffuse alveolar delivery; b) a single nasal instillation of GAPDH RNAi in SAM (10- 15mu/l), compared with scrampled GAPDH RNAi, resulted in a 60-70% down-regulation, in a lung specific manner, of GAPDH protein from 24 h through 7 days; c) nasal instillation of retinoic acid (RA) in SAM caused a 4.6-fold increase in lung concentration of the mRNA of a marker protein in a lung specific manner; an equal concentration of RA given intraperitonealy caused a 1.8-fold increase in the marker mRNA in lung and an increase in brain and other organs.
Our specific aims, using wild type and mutant mice, morphometric, and lung gene-expression profiling, are: 1. Determine the developmental time of onset of the ER alveolar phenotype; 2. Identify the ERs that mediate the ovariectomy-induced destruction of alveoli, and 3. Identify the upstream modulators that initiate the signal cascade required for estrogen-induced alveolar regeneration that follows ovariectomy. We think the new information generated since the first amended application, including the ability to alter expression of specific genes in a simple, noninvasive, lung specific manner, our extensive experience with morphometry, and now with lung gene profiling, will allow us to complete the proposed work.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL073558-02
Application #
6920656
Study Section
Special Emphasis Panel (ZRG1-RES-D (03))
Program Officer
Berberich, Mary Anne
Project Start
2004-07-10
Project End
2008-06-30
Budget Start
2005-07-01
Budget End
2006-06-30
Support Year
2
Fiscal Year
2005
Total Cost
$388,000
Indirect Cost
Name
Georgetown University
Department
Biology
Type
Schools of Medicine
DUNS #
049515844
City
Washington
State
DC
Country
United States
Zip Code
20057
Massaro, Donald; Massaro, Gloria DeCarlo (2008) Apoetm1Unc mice have impaired alveologenesis, low lung function, and rapid loss of lung function. Am J Physiol Lung Cell Mol Physiol 294:L991-7
Massaro, Donald; Clerch, Linda Biadasz; Massaro, Gloria DeCarlo (2007) Estrogen receptor-alpha regulates pulmonary alveolar loss and regeneration in female mice: morphometric and gene expression studies. Am J Physiol Lung Cell Mol Physiol 293:L222-8
Massaro, Donald; Alexander, Emma; Reiland, Kristin et al. (2007) Rapid onset of gene expression in lung, supportive of formation of alveolar septa, induced by refeeding mice after calorie restriction. Am J Physiol Lung Cell Mol Physiol 292:L1313-26
Massaro, Donald; Massaro, Gloria DeCarlo (2007) Developmental alveologenesis: longer, differential regulation and perhaps more danger. Am J Physiol Lung Cell Mol Physiol 293:L568-9
Massaro, Donald; Massaro, Gloria Decarlo (2006) Estrogen receptor regulation of pulmonary alveolar dimensions: alveolar sexual dimorphism in mice. Am J Physiol Lung Cell Mol Physiol 290:L866-70
Massaro, Donald; Massaro, Gloria Decarlo (2006) Toward therapeutic pulmonary alveolar regeneration in humans. Proc Am Thorac Soc 3:709-12