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1.  Gene Deletion of VIP Leads to Increased Mortality Associated with Progressive Right Ventricular Hypertrophy 
Vasoactive Intestinal Peptide (VIP) knockout mice exhibit asthma, pulmonary hypertension, and left ventricular wall thinning. Humans with these disorders have premature death. We show here that VIP KO mice have reduced survival (100% mortality at 20 months), vs. 100% survival among WT C57BL/6 mice. Moreover, the ratios of weights of right ventricle divided by left ventricle plus septum were progressively increased in VIP KO mice with age. Core temperatures were lower in VIP KO mice when compared to WT littermates, with an associated pro-inflammatory cytokine milieu. Overall, our results indicate that VIP is important for survival in mice. Its absence leads to increased mortality, with progressive right ventricular hypertrophy as a surrogate of pulmonary hypertension, lower body weight, hypothermia, and pro-inflammatory milieu. These studies support VIP as a novel therapeutic agent in pulmonary hypertension.
PMCID: PMC4031245  PMID: 24860842
asthma; knockout mice; pulmonary hypertension; right heart failure; Vasoactive Intestinal Peptide; VIP
2.  Occupational Lung Diseases among Soldiers Deployed to Iraq and Afghanistan 
Occupational medicine & health affairs  2013;1:10.4172/2329-6879.1000117.
Military personnel deployed to Iraq and Afghanistan, from 2004 to the present, has served in a setting of unique environmental conditions. Among these are exposures to burning trash in open air “burn pits” lit on fire with jet fuel JP-8. Depending on trash burned--water bottles, styrofoam trays, medical waste, unexploded munitions, and computers--toxins may be released such as dioxins and n-hexane and benzene. Particulate matter air pollution culminates from these fires and fumes. Additional environmental exposures entail sandstorms (Haboob, Shamal, and Sharqi) which differ in direction and relationship to rain. These wars saw the first use of improvised explosive devices (roadside phosphate bombs),as well as vehicle improvised explosive devices (car bombs), which not only potentially aerosolize metals, but also create shock waves to induce lung injury via blast overpressure. Conventional mortar rounds are also used by Al Qaeda in both Iraq and Afghanistan. Outdoor aeroallergens from date palm trees are prevalent in southern Iraq by the Tigris and Euphrates rivers, while indoor aeroallergen aspergillus predominates during the rainy season. High altitude lung disease may also compound the problem, particularly in Kandahar, Afghanistan. Clinically, soldiers may present with new-onset asthma or fixed airway obstruction. Some have constrictive bronchiolitis and vascular remodeling on open lung biopsy - despite having normal spirometry and chest xrays and CT scans of the chest. Others have been found to have titanium and other metals in the lung (rare in nature). Still others have fulminant biopsy-proven sarcoidiosis. We found DNA probe–positive Mycobacterium Avium Complex in lung from a soldier who had pneumonia, while serving near stagnant water and camels and goats outside Abu Gharib. This review highlights potential exposures, clinical syndromes, and the Denver Working Group recommendations on post-deployment health.
PMCID: PMC3891866  PMID: 24443711
Burn pits; Aeroallergenaspergillus; Bronchiolitis; Mycobacterium avium complex
3.  Allergic reaction to mint leads to asthma 
Allergy & Rhinology  2011;2(1):43-45.
Respiratory and cutaneous adverse reactions to mint can result from several different mechanisms including IgE-mediated hypersensitivity, delayed-type hypersensitivity (contact dermatitis), and nonimmunologic histamine release. Reactions to cross-reacting plants of the Labiatae family, such as oregano and thyme, as well as to the chemical turpentine, may clue the clinician in on the diagnosis of mint allergy. Contact dermatitis can result from menthol in peppermint. Contact allergens have been reported in toothpastes, which often are mint-flavored. Allergic asthma from mint is less well-recognized. A case of a 54-year-old woman with dyspnea on exposure to the scent of peppermint is presented in whom mint exposure, as seemingly innocuous as the breath of others who had consumed Tic Tac candies, exacerbated her underlying asthma. This case highlights the importance of testing with multiple alternative measures of specific IgE to mint, including skin testing with mint extract, and skin testing with fresh mint leaves. Additionally, this cases suggests that asthma can result from inhaling the scent of mint and gives consideration to obtaining confirmatory pre- and postexposure pulmonary function data by both impulse oscillometry and spirometry.
PMCID: PMC3390130  PMID: 22852115
Allergic asthma; allergy; asthma; contact dermatitis; IgE; mint; mint leaves; peppermint; skin test
4.  VIP Gene Deletion in Mice Causes Cardiomyopathy Associated with Upregulation of Heart Failure Genes 
PLoS ONE  2013;8(5):e61449.
Vasoactive Intestinal Peptide (VIP), a pulmonary vasodilator and inhibitor of vascular smooth muscle proliferation, is absent in pulmonary arteries of patients with idiopathic pulmonary arterial hypertension (PAH). We previously determined that targeted deletion of the VIP gene in mice leads to PAH with pulmonary vascular remodeling and right ventricular (RV) dilatation. Whether the left ventricle is also affected by VIP gene deletion is unknown. In the current study, we examined if VIP knockout mice (VIP−/−) develop both right (RV) and left ventricular (LV) cardiomyopathy, manifested by LV dilatation and systolic dysfunction, as well as overexpression of genes conducive to heart failure.
We examined VIP−/−and wild type (WT) mice using Magnetic Resonance Imaging (MRI) for evidence of cardiomyopathy associated with biventricular dilation and wall thickness changes. Lung tissue from VIP−/− and WT mice was subjected to whole-genome gene microarray analysis.
Lungs from VIP−/− mice showed overexpression of cardiomyopathy genes: Myh1 was upregulated 224 times over WT, and Mylpf was increased 72 fold. Tnnt3 was increased 105 times and tnnc2 181 fold. Hearts were dilated in VIP−/− mice, with thinning of LV wall and increase in RV and LV chamber size, though RV enlargement varied. Weights of VIP−/− mice were consistently lower.
Critically-important heart failure-related genes are upregulated in VIP−/− mice associated with the spontaneous cardiomyopathy phenotype, involving both left and right ventricles, suggesting that loss of the VIP gene orchestrates a panoply of pathogenic genes which are detrimental to both left and right cardiac homeostasis.
PMCID: PMC3659051  PMID: 23700405
5.  Health Benefits from Large-Scale Ozone Reduction in the United States 
Environmental Health Perspectives  2012;120(10):1404-1410.
Background: Exposure to ozone has been associated with adverse health effects, including premature mortality and cardiopulmonary and respiratory morbidity. In 2008, the U.S. Environmental Protection Agency (EPA) lowered the primary (health-based) National Ambient Air Quality Standard (NAAQS) for ozone to 75 ppb, expressed as the fourth-highest daily maximum 8-hr average over a 24-hr period. Based on recent monitoring data, U.S. ozone levels still exceed this standard in numerous locations, resulting in avoidable adverse health consequences.
Objectives: We sought to quantify the potential human health benefits from achieving the current primary NAAQS standard of 75 ppb and two alternative standard levels, 70 and 60 ppb, which represent the range recommended by the U.S. EPA Clean Air Scientific Advisory Committee (CASAC).
Methods: We applied health impact assessment methodology to estimate numbers of deaths and other adverse health outcomes that would have been avoided during 2005, 2006, and 2007 if the current (or lower) NAAQS ozone standards had been met. Estimated reductions in ozone concentrations were interpolated according to geographic area and year, and concentration–response functions were obtained or derived from the epidemiological literature.
Results: We estimated that annual numbers of avoided ozone-related premature deaths would have ranged from 1,410 to 2,480 at 75 ppb to 2,450 to 4,130 at 70 ppb, and 5,210 to 7,990 at 60 ppb. Acute respiratory symptoms would have been reduced by 3 million cases and school-loss days by 1 million cases annually if the current 75-ppb standard had been attained. Substantially greater health benefits would have resulted if the CASAC-recommended range of standards (70–60 ppb) had been met.
Conclusions: Attaining a more stringent primary ozone standard would significantly reduce ozone-related premature mortality and morbidity.
PMCID: PMC3491929  PMID: 22809899
health benefits; health impact assessment; ozone; standards
6.  VIP Regulates the Development & Proliferation of Treg in vivo in spleen 
Mounting evidence supports a key role for VIP as an anti-inflammatory agent and promoter of immune tolerance. It suppresses TNF-α and other inflammatory cytokines and chemokines, upregulates anti-inflammatory IL-10, and promotes immune tolerant cells called T regulatory (Treg) cells. VIP KO mice have recently been demonstrated to have spontaneous airway and pulmonary perivascular inflammatory responses, as part of asthma-like and pulmonary hypertension phenotypes, respectively. Both inflammatory responses are correctable with VIP. Focusing on this model, we have now investigated the influence of VIP not only on inflammatory cells but also on Treg cells.
Using flow cytometric analysis, we examined the relative preponderance of CD25+CD4+ cells and anti-inflammatory Treg cells, in extracts of thymus and spleen from VIP KO mice (5 VIP KO; 5 VIP KO+ VIP; 10 wild-type). This method allowed antibody-based flow cytometric identification of Treg cells using surface markers CD25 and CD4, along with the: 1) intracellular activation marker FoxP3; and 2) Helios, which distinguishes cells of thymic versus splenic derivation.
Deletion of the VIP gene results in: 1) CD25+CD4- cell accumulation in the thymus, which is corrected by VIP treatment; 2) more Treg in thymus lacking Foxp3 expression, suggesting VIP is necessary for immune tolerance; and, 3) a tendency towards deficiency of Treg cells in the spleen, which is normalized by VIP treatment. Treg lacking Helios are induced by VIP intrasplenically rather than by migration from the thymus. These results confirm the dual role of VIP as an anti-inflammatory and immune tolerance-promoting agent.
PMCID: PMC3286388  PMID: 22126441
7.  Vasoactive Intestinal Peptide Knockout (VIP KO) mouse model of sulfite-sensitive asthma: up-regulation of novel lung carbonyl reductase 
BMC Immunology  2011;12:66.
We earlier reported spontaneous features of asthma in Vasoactive Intestinal Peptide knockout mice (VIP KO): 1) peribronchiolar airway inflammation, with accumulation of lymphocytes and eosinophils, 2) pro-inflammatory cytokine production of IL-5, IL-6, with IFN-γ, and 3) airway hyper-responsiveness to inhaled methacholine. In human asthma, a phenotype with sulfite sensitivity leads to airway inflammation and hyper-responsiveness to inhaled sulfites, and is associated with upregulation of anti-oxidant protein lung carbonyl reductase. For the present experiments, we examined the role of VIP in modulating anti-oxidant genes and their proteins, including lung carbonyl reductase.
Four male VIP KO mice and four wild-type age- and gender matched mice had lungs examined for whole genome microarray and a proteomics approach using mass spectrometry. The proteomics analysis revealed that a novel variant of anti-oxidant protein lung carbonyl reductase (car3) was uniquely and markedly elevated in the VIP KO mice. RT-PCR indicated that carbonic anhydrase 3, which is an anti-oxidant protein, was elevated in the VIP KO mice.
These data support the concept that VIP influences the endogenous oxidant/antioxidant balance. One potential implication is that VIP and its analogues may be used to treat inflammatory diseases, including asthma.
PMCID: PMC3277465  PMID: 22103391
8.  VIP and endothelin receptor antagonist: An effective combination against experimental pulmonary arterial hypertension 
Respiratory Research  2011;12(1):141.
Pulmonary Arterial Hypertension (PAH) remains a therapeutic challenge, and the search continues for more effective drugs and drug combinations. We recently reported that deletion of the vasoactive intestinal peptide (VIP) gene caused the spontaneous expression of a PH phenotype that was fully corrected by VIP. The objectives of this investigation were to answer the questions: 1) Can VIP protect against PH in other experimental models? and 2) Does combining VIP with an endothelin (ET) receptor antagonist bosentan enhance its efficacy?
Within 3 weeks of a single injection of monocrotaline (MCT, s.c.) in Sprague Dawley rats, PAH developed, manifested by pulmonary vascular remodeling, lung inflammation, RV hypertrophy, and death within the next 2 weeks. MCT-injected animals were either untreated, treated with bosentan (p.o.) alone, with VIP (i.p.) alone, or with both together. We selected this particular combination upon finding that VIP down-regulates endothelin receptor expression which is further suppressed by bosentan. Therapeutic outcomes were compared as to hemodynamics, pulmonary vascular pathology, and survival.
Treatment with VIP, every other day for 3 weeks, begun on the same day as MCT, almost totally prevented PAH pathology, and eliminated mortality for 45 days. Begun 3 weeks after MCT, however, VIP only partially reversed PAH pathology, though more effectively than bosentan. Combined therapy with both drugs fully reversed the pathology, while preventing mortality for at least 45 days.
1) VIP completely prevented and significantly reversed MCT-induced PAH; 2) VIP was more effective than bosentan, probably because it targets a wider range of pro-remodeling pathways; and 3) combination therapy with VIP plus bosentan was more effective than either drug alone, probably because both drugs synergistically suppressed ET-ET receptor pathway.
PMCID: PMC3210095  PMID: 22029879
Pulmonary Hypertension; Vasoactive Intestinal Peptide; Endothelin Receptor Antagonist; Pulmonary Vascular Remodeling; Monocrotaline

Results 1-8 (8)