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Bronchopulmonary dysplasia (BPD) is potentially one of the most devastating conditions in premature infants with longstanding consequences involving multiple organ systems including adverse effects on pulmonary function and neurodevelopmental outcome. Here we review recent studies in the field to summarize the progress made in understanding in the pathophysiology, prognosis, prevention, and treatment of BPD in the last decade. The work reviewed includes the progress in understanding its pathobiology, genomic studies, ventilatory strategies, outcomes, and therapeutic interventions. We expect that this review will help guide clinicians to treat premature infants at risk for BPD better and lead researchers to initiate further studies in the field. [ABSTRACT FROM AUTHOR]

The pulmonary alveolar lipofibroblast was first reported in 1970. Since then its development, structure, function and molecular characteristics have been determined. Its capacity to actively absorb, store and ‘traffic’ neutral lipid for protection of the alveolus against oxidant injury, and for the active supply of substrate for lung surfactant phospholipid production have offered the opportunity to identify a number of specialized functions of these strategically placed cells. Namely, Parathyroid Hormone-related Protein (PTHrP) signaling, expression of Adipocyte Differentiation Related Protein, leptin, peroxisome proliferator activator receptor gamma, and the prostaglandin E2 receptor EP2- which are all stretch-regulated, explaining how and why surfactant production is ‘on-demand’ in service to ventilation–perfusion matching. Because of the central role of the lipofibroblast in vertebrate lung physiologic evolution, it is a Rosetta Stone for understanding how and why the lung evolved in adaptation to terrestrial life, beginning with the duplication of the PTHrP Receptor some 300 mya. Moreover, such detailed knowledge of the workings of the lipofibroblast have provided insight to the etiology and effective treatment of Bronchopulmonary Dysplasia based on physiologic principles rather than on pharmacology. [ABSTRACT FROM AUTHOR]

Significance: Oxygen, the main mode of support for premature infants with immature lungs, can cause toxicity by producing reactive oxygen species (ROS) that disrupt homeostasis; yet, these same molecules were entrained to promote vertebrate lung phylogeny. By providing a deeper understanding of this paradox, we propose physiologically rational strategies to prevent chronic lung disease (CLD) of prematurity. Recent Advances: To prevent neonatal hyperoxic lung damage biologically, we have exploited the alveolar defense mechanism(s) that evolutionarily evolved to combat increased atmospheric oxygen during the vertebrate water to land transition. Critical Issues: Over the course of vertebrate lung evolution, ROS promoted the formation of lipofibroblasts, specialized adepithelial cells, which protect the alveoli against oxidant injury; peroxisome proliferator-activated receptor gamma (PPARγ), the master switch for lipofibroblast differentiation, prevents such oxidant lung injury, both by directly promoting mesodermal differentiation and its antioxidant defenses, and indirectly by stimulating the developmental epithelial-mesenchymal paracrine interactions that have physiologically determined lung surfactant production in accord with the lung's phylogenetic adaptation to atmospheric oxygen, preventing Respiratory Distress Syndrome at birth. Future Directions: The molecular strategy (PPARγ agonists) to prevent CLD of prematurity, proposed by us, although seems to be robust, effective, and safe under experimental conditions, it awaits detailed pharmacokinetic and pharmacodynamic studies for its safe and effective clinical translation to human infants. Antioxid. Redox Signal. 21, 1893-1904. [ABSTRACT FROM AUTHOR]

Maternal food restriction (MFR) during pregnancy affects pulmonary surfactant production in the intrauterine growth-restricted (IUGR) offspring through unknown mechanisms. Since pulmonary surfactant production is regulated by maternal and fetal corticosteroid levels, both known to be increased in IUGR pregnancies, we hypothesized that metyrapone (MTP), a glucocorticoid synthesis inhibitor, would block the effects of MFR on surfactant production in the offspring. Three groups of pregnant rat dams were used (1) control dams fed ad libitum; (2) MFR (50% reduction in calories) from days 10 to 22 of gestation; and (3) MFR + MTP in drinking water (0.5 mg/mL), days 11 to 22 of gestation. At 5 months, the MFR offspring weighed significantly more, had reduced alveolar number, increased septal thickness, and decreased surfactant protein and phospholipid synthesis. These MFR-induced effects were normalized by the antiglucocorticoid MTP, suggesting that the stress of MFR causes hypercorticoidism, altering lung structure and function in adulthood. [ABSTRACT FROM AUTHOR]

Asthma is a major public health hazard worldwide. Its transgenerational inheritance has been inferred from epidemiological studies. More recently, using nicotine as a proxy for maternal smoking, we have demonstrated that an asthmalike phenotype can be inherited by rat offspring for up to two generations, i.e., multigenerationally, after the initial intrauterine exposure. We hypothesized that asthma transmission to offspring following perinatal nicotine exposure is not restricted up to F2 generation, but it also extends to subsequent generations. To test this hypothesis, using a well-established rat model of nicotine exposureinduced childhood asthma, we determined if perinatal nicotine exposure of F0 gestating dams would transmit asthma transgenerationally to F3 offspring. We now extend our findings to third-generation offspring, including abnormal pulmonary function, particularly as it relates to the occurrence in the upper airway exclusively in males, and to its effects on molecular functional markers (fibronectin and peroxisome proliferator-activated receptor γ), previously shown to be consistent with the asthma phenotype, herein expressed in fibroblasts isolated from the lung. These data, for the first time, demonstrate the transgenerational transmission of the asthma phenotype to F3 offspring following perinatal nicotine exposure of F0 dams. [ABSTRACT FROM AUTHOR]

Background: By altering specific developmental signaling pathways that are necessary for fetal lung development, perinatal nicotine exposure affects lung growth and differentiation, resulting in the offsprings' predisposition to childhood asthma; peroxisome proliferator-activated receptor gamma (PPARg) agonists can inhibit this effect. However, whether the perinatal nicotine-induced asthma risk is restricted to nicotine-exposed offspring only; whether it can be transmitted to the next generation; and whether PPARg agonists would have any effect on this process are not known. Methods: Time-mated Sprague Dawley rat dams received either placebo or nicotine (1 mg/kg, s.c.), once daily from day 6 of gestation to postnatal day (PND) 21. Following delivery, at PND21, generation 1 (F1) pups were either subjected to pulmonary function tests, or killed to obtain their lungs, tracheas, and gonads to determine the relevant protein markers (mesenchymal contractile proteins), global DNA methylation, histone 3 and 4 acetylation, and for tracheal tension studies. Some F1 animals were used as breeders to generate F2 pups, but without any exposure to nicotine in the F1 pregnancy. At PND21, F2 pups underwent studies similar to those performed on F1 pups. Results: Consistent with the asthma phenotype, nicotine affected lung function in both male and female F1 and F2 offspring (maximal 250% increase in total respiratory system resistance, and 84% maximal decrease in dynamic compliance following methacholine challenge; P < 0.01, nicotine versus control; P < 0.05, males versus females; and P > 0.05, F1 versus F2), but only affected tracheal constriction in males (51% maximal increase in tracheal constriction following acetylcholine challenge, P < 0.01, nicotine versus control; P < 0.0001, males versus females; P > 0.05, F1 versus F2); nicotine also increased the contractile protein content of whole lung (180% increase in fibronectin protein levels, P < 0.01, nicotine versus control, and P < 0.05, males versus females) and isolated lung fibroblasts (for example, 45% increase in fibronectin protein levels, P < 0.05, nicotine versus control), along with decreased PPARg expression (30% decrease, P < 0.05, nicotine versus control), but only affected contractile proteins in the male trachea (P < 0.05, nicotine versus control, and P < 0.0001, males versus females). All of the nicotineinduced changes in the lung and gonad DNA methylation and histone 3 and 4 acetylation were normalized by the PPARg agonist rosiglitazone except for the histone 4 acetylation in the lung. Conclusions: Germline epigenetic marks imposed by exposure to nicotine during pregnancy can become permanently programmed and transferred through the germline to subsequent generations, a ground-breaking finding that shifts the current asthma paradigm, opening up many new avenues to explore. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal interactions mediated by soluble growth factors determine the evolution of vertebrate lung physiology, including development, homeostasis, and repair. The final common pathway for all of these positively adaptive properties of the lung is the expression of epithelial parathyroid-hormone-related protein, and its binding to its receptor on the mesenchyme, inducing PPARγ expression by lipofibroblasts. Lipofibroblasts then produce leptin, which binds to alveolar type II cells, stimulating their production of surfactant, which is necessary for both evolutionary and physiologic adaptation to atmospheric oxygen from fish toman. A wide variety of molecular insults disrupt such highly evolved physiologic cell-cell interactions, ranging from overdistention to oxidants, infection, and nicotine, all of which predictably cause loss of mesenchymal peroxisome-proliferator-activated receptor gamma (PPARγ) expression and the transdifferentiation of lipofibroblasts to myofibroblasts, the signature cell type for lung fibrosis. By exploiting such deep cell-molecular functional homologies as targets for leveraging lung homeostasis, we have discovered that we can effectively prevent and/or reverse the deleterious effects of these pathogenic agents, demonstrating the utility of evolutionary biology for the prevention and treatment of chronic lung disease. By understanding mechanisms of health and disease as an evolutionary continuum rather than as dissociated processes, we can evolve predictive medicine. [ABSTRACT FROM AUTHOR]

The underlying mechanisms and effector molecules involved in mediating in utero smoke exposure-induced effects on the developing lung are only beginning to be understood. However, the effects of a newly discovered category of smoke, i.e., thirdhand smoke (THS), on the developing lung are completely unknown. We hypothesized that, in addition to nicotine, other components of THS would also affect lung development adversely. Fetal rat lung explants were exposed to nicotine, 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal (NNA), or 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), the two main tobacco-specific N-nitrosamine constituents of THS, for 24 h. We then determined key markers for alveolar paracrine signaling [epithelial differentiation markers surfactant phospholipid and protein synthesis; mesenchymal differentiation markers peroxisome proliferator-activated receptor γ (PPAR-γ), fibronectin and calponin], the BCL-2-to-Bax ratio (BCL-2/Bax), a marker of apoptosis and the involvement of nicotinic acetylcholine receptors (nAChR)-α3 and -α7 in mediating NNA's and NNK's effects on the developing lung. Similar to the effects of nicotine, exposure of the developing lung to either NNK or NNA resulted in disrupted homeostatic signaling, indicated by the downregulation of PPAR-γ, upregulation of fibronectin and calponin protein levels, decreased BCL-2/Bax, and the accompanying compensatory stimulation of surfactant phospholipid and protein synthesis. Furthermore, nAChR-α3 and -α7 had differential complex roles in mediating these effects. NNK and NNA exposure resulted in breakdown of alveolar epithelial-mesenchymal cross-talk, reflecting lipofibroblast-to-myofibroblast transdifferentiation, suggesting THS constituents as possible novel contributors to in utero smoke exposure-induced pulmonary damage. These data are particularly relevant for designing specific therapeutic strategies, and for formulating public health policies to minimize THS exposure. [ABSTRACT FROM AUTHOR]

Adipocyte differentiation--related protein (ADRP) is a critically important protein that mediates lipid uptake, and is highly expressed in lung lipofibroblasts (LIFs). Triacylglycerol secreted from the pulmonary circulation and stored in lipid storage droplets is a robust hormonal-, growth factor--, and stretch-regulated precursor for surfactant phospholipid synthesis by alveolar type II epithelial (ATII) cells. A549 lung epithelial cells rapidly take up green fluorescent protein (GFP)-ADRP fusion protein--associated lipid droplets (LDs) in a dose-dependent manner. The LDs initially localize to the perinuclear region of the cell, followed by localization in the cytoplasm. Uptake of ADRP-LDs causes a time- and dose-dependent increase in surfactant protein-B (SP-B) expression. This mechanism can be inhibited by either actinomycin D or cycloheximide, indicating that ADRP-LDs induce newly synthesized SP-B. ADRP-LDs concomitantly stimulate saturated phosphatidylcholine (satPC) synthesis by A549 cells, which is inhibited by ADRP antibody, indicating that this is a receptor-mediated mechanism. Intravenous administration of GFP-ADRP LDs to adult rats results in dose-dependent increases in lung ADRP and SP-B expression. These data indicate that lipofibroblast-derived ADRP coordinates ATII cells'' synthesis of the surfactant phospholipid--protein complex by stimulating both satPC and SP-B. The authors propose, therefore, that ADRP is the physiologic determinant for the elusive coordinated, stoichiometric synthesis of surfactant phospholipid and protein by pulmonary ATII cells. [ABSTRACT FROM AUTHOR]

The physiological development and homeostasis of the lung alveolus is determined by the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) by the interstitial lipofibroblast. We have recently shown (Dasgupta C et al., Am J Physiol Lung Cell Mol Physiol 296: L1031-L1041, 2009.) that PPAR-γ agonists administered postnatally accelerate lung maturation and prevent hyperoxia-induced lung injury. However, whether the same occurs antenatally is not known. The objective of this study was to test the hypothesis that the potent PPAR- γ agonist rosiglitazone (RGZ), administered antenatally, enhances fetal lung maturation and protects against hyperoxia-induced neonatal lung injury. Sprague-Dawley rat dams were administered either diluent or RGZ (3 mg/kg), at late gestation, to determine its effect on lung maturation and on hyperoxia (95% O2 exposure for 24 h)-induced neonatal lung injury. The lungs were examined for the expression of specific markers of alveolar development (surfactant proteins A and B, cholinephosphate cytidylyltransferase-a, leptin receptor, triglyceride uptake, and [³H]choline incorporation into saturated phosphatidylcholine) and injury/repair, in particular, the markers of transforming growth factor-β signaling (activin receptor-like kinase-5, SMAD3, lymphoid enhancer factor-1, fibronectin, and calponin). Overall, antenatal RGZ accelerated lung maturation and blocked the inhibition of alveolar sacculation and septal wall thinning by hyperoxia. RGZ specifically stimulated the development of the alveolar epithelial type II cell, the lipofibroblast, and the vasculature. The increased expression of the transforming growth factor-β intermediates, such as SMAD3 and lymphoid enhancer factor-1, implicated in hyperoxic lung injury, was also blocked by antenatal RGZ treatment. In conclusion, PPAR-γ agonists can enhance fetal lung maturation and can effectively prevent hyperoxia-induced neonatal lung injury. [ABSTRACT FROM AUTHOR]

Late preterm births have been on the increase. Though the reasons for the increase in late preterm births are unclear, non-medically indicated inductions and cesarean sections seem to be the significant preventable contributors. Late preterm infants are typically healthier than very preterm infants, but compared to term infants they are at significantly increased risk of both short and long term morbidity and mortality. In the short term they have increased rates of feeding difficulties, hypoglycemia, jaundice, temperature instability, apnea, respiratory distress and sepsis evaluation compared to term infants. Emerging data also suggest a higher rate of long-term neurodevelopmental, social, and medical morbidity. Therefore, if elective induction of labor or cesarean section at late preterm gestation (34-36 weeks of gestational age) is considered for either maternal or fetal indications, the risk and benefits should be carefully examined. The family and physician should discuss that elective delivery of late preterm infants is not recommended unless absolutely indicated. Due to a considerably higher risk of morbidity and mortality, developing and testing new paradigms of obstetric and fetal management for pregnancies with potential for late preterm delivery are a logical objective. For example, strategies to enhance fetal physiologic maturation when late preterm delivery is unavoidable need to be explored. [ABSTRACT FROM AUTHOR]

There is extensive epidemiologic and experimental evidence from both animal and human studies that demonstrates detrimental long-term pulmonary outcomes in the offspring of mothers who smoke during pregnancy. However, the molecular mechanisms underlying these associations are not understood. Therefore, it is not surprising that that there is no effective intervention to prevent the damaging effects of perinatal smoke exposure. Using a biologic model of lung development, homeostasis, and repair, we have determined that in utero nicotine exposure disrupts specific molecular paracrine communications between epithelium and interstitium that are driven by parathyroid hormone-related protein and peroxisome proliferator-activated receptor (PPAR)γ, resulting in transdifferentiation of lung lipofibroblasts to myofibroblasts, i.e., the conversion of the lipofibroblast phenotype to a cell type that is not conducive to alveolar homeostasis, and is the cellular hallmark of chronic lung disease, including asthma. Furthermore, we have shown that by molecularly targeting PPARγ expression, nicotine-induced lung injury can not only be significantly averted, it can also be reverted. The concept outlined by us differs from the traditional paradigm of teratogenic and toxicological effects of tobacco smoke that has been proposed in the past. We have argued that since nicotine alters the normal homeostatic epithelial-mesenchymal paracrine signaling in the developing alveolus, rather than causing totally disruptive structural changes, it offers a unique opportunity to prevent, halt, and/or reverse this process through targeted molecular manipulations. [ABSTRACT FROM AUTHOR]

Speakers in this symposium presented examples of respiratory regulation that broadly illustrate principles of evolution from whole organ to genes. The swim bladder and lungs of aquatic and terrestrial organisms arose independently from a common primordial "respiratory pharynx" but not from each other. Pathways of lung evolution are similar between crocodiles and birds but a low compliance of mammalian lung may have driven the development of the diaphragm to permit lung inflation during inspiration. To meet the high oxygen demands of flight, bird lungs have evolved separate gas exchange and pump components to achieve unidirectional ventilation and minimize dead space. The process of "screening" (removal of oxygen from inspired air prior to entering the terminal units) reduces effective alveolar oxygen tension and potentially explains why nonathletic large mammals possess greater pulmonary diffusing capacities than required by their oxygen consumption. The "primitive" central admixture of oxygenated and deoxygenated blood in the incompletely divided reptilian heart is actually co-regulated with other autonomic cardiopulmonary responses to provide flexible control of arterial oxygen tension independent of ventilation as well as a unique mechanism for adjusting metabolic rate. Some of the most ancient oxygen-sensing molecules, i.e., hypoxiainducible factor-1alpha and erythropoietin, are up-regulated during mammalian lung development and growth under apparently normoxic conditions, suggesting functional evolution. Normal alveolarization requires pleiotropic growth factors acting via highly conserved cell--cell signal transduction, e.g., parathyroid hormone-related protein transducing at least partly through the Wingless/int pathway. The latter regulates morphogenesis from nematode to mammal. If there is commonality among these diverse respiratory processes, it is that all levels of organization, from molecular signaling to structure to function, co-evolve progressively, and optimize an existing gas-exchange framework. [ABSTRACT FROM AUTHOR]

Chorioamnionitis alters lung development, resulting in a paradoxical decrease in the incidence of respiratory distress syndrome but an increase in the incidence of bronchopulmonary dysplasia (BPD). The mechanism(s) underlying this disparity in the pulmonary outcomes is not known. We hypothesized that specific alterations in alveolar epithelial-mesenchymal interactions might explain this apparent disparity in the pulmonary outcome following chorioamnionitis. We determined the effects of lipopolysaccharide (LPS) on parathyroid hormone-related protein (PTHrP)-driven epithelial-mesenchymal interactions that are essential for normal lung development and homeostasis. Lung explants from embryonic day 19.5 Sprague-Dawley rat fetuses were treated with LPS with or without a PTHrP pathway agonist, prostaglandin J2 (PGJ2). LPS treatment affected the production of proinflammatory cytokines and the expression of the key markers of the epithelial-mesenchymal paracrine interactions in a time-dependent manner. At 6 h, there was a significant increase in the expression of PTHrP and the other key markers of alveolar homeostasis without any significant effect on α-smooth muscle actin (αSMA). In contrast, at 72 h, there was a significant decrease in the expression of PTHrP and the other key markers of alveolar homeostasis accompanied by a significant increase in αSMA expression. The cytokine and molecular changes at 72 h were completely prevented by the concomitant treatment with PGJ2. We speculate that these data provide a likely mechanism for the acute stimulation of lung differentiation, accompanied paradoxically by BPD following chorioamnionitis, and suggest that by specifically targeting PTHrP signaling, the inflammation-induced molecular injury that is known to result in BPD can be prevented. [ABSTRACT FROM AUTHOR]

Nicotine exposure disrupts the parathyroid hormone-related protein (PTHrP)-driven alveolar epithelial-mesenchymal paracrine-signaling pathway, resulting in the transdifferentiation of pulmonary lipofibroblasts (LIFs) to myofibroblasts (MYFs), which seems to be central to altered pulmonary development and function in infants born to mothers who smoke during pregnancy. Modulation of PTHrP-driven signaling can almost completely prevent nicotine-induced LIF-to-MYF transdifferentiation. However, once this process has occurred, whether it can be reversed is not known. Our objective was to determine if nicotine-induced LIF-to-MYF transdifferentiation could be reversed by specifically targeting the PTHrP-mediated alveolar epithelial-mesenchymal paracrine signaling. WI38 cells, a human embryonic pulmonary fibroblast cell line, were initially treated with nicotine for 7 days and LIF-to-MYF transdifferentiation was confirmed by determining the downregulation of the key lipogenic marker, peroxisome proliferator-activated receptor γ (PPARγ) and upregulation of the key myogenic marker, α-smooth muscle actin (αSMA). Because downregulation of the PPARγ signaling pathway is the key determinant of LIF-to-MYF transdifferentiation, cells were treated with three agonists of this pathway, PTHrP, dibutryl cAMP (DBcAMP), or rosiglitazone (RGZ) for 7 days, and the expression of the PTHrP receptor, PPARγ, αSMA, and calponin was determined by Western analysis and immunohistochemistry. Simultaneously, fibroblast function was characterized by measuring their capacity to take up triglycerides. Nicotine-induced LIF-to-MYF transdifferentiation was almost completely reversed by treatment with RGZ, PTHrP, or DBcAMP, as determined by protein and functional assays. Using a specific molecular approach and targeting specific molecular intermediates in the PTHrP signaling pathway, to our knowledge, this for the first time, demonstrates the reversibility of nicotine-induced LIF-to-MYF transdifferentiation, suggesting not only the possibility of prevention but also the potential for reversal of nicotine-induced lung injury. [ABSTRACT FROM AUTHOR]

We recently suggested that alveolar interstitial fibroblast-to-myofibroblast transdifferentiation may be a key mechanism underlying in utero nicotine-induced lung injury. However, the effects of in utero nicotine exposure on fetal alveolar type II (ATII) cells have not been fully determined. Placebo, nicotine (1 mg/kg), or nicotine (1 mg/kg) + the peroxisome proliferator-activated receptor (PPAR)-γ agonist prostaglandin J2 (PGJ2, 0.3 mg/kg) was administered intraperitoneally once daily to time-mated pregnant Sprague-Dawley rats from embryonic day 6 until their death on embryonic day 20. Fetal ATII cells were isolated, and ATII cell proliferation, differentiation (surfactant synthesis), and metabolism (metabolic profiling with the stable isotope [1,2-13C2]-D-glucose) were determined after nicotine exposure in utero or in vitro. In utero nicotine exposure significantly stimulated ATII cell proliferation, differentiation, and metabolism. Although the effects on ATII cell proliferation and metabolism were almost completely prevented by concomitant treatment with PGJ2, the effects on surfactant synthesis were not. On the basis of in utero and in vitro data, we conclude that surfactant synthesis is stimulated by nicotine's direct effect on ATII cells, whereas cell proliferation and metabolism are affected via a paracrine mechanism(s) secondary to its effects on the adepithelial fibroblasts. These data provide evidence for direct and indirect effects of in utero nicotine exposure on fetal ATII cells that could permanently alter the ‘developmental program’ of the developing lung. More importantly, concomitant administration of PPAR-γ agonists can effectively attenuate many of the effects of in utero exposure to nicotine on ATII cells. [ABSTRACT FROM AUTHOR]

The lipid-containing alveolar interstitial fibroblast (lipofibroblast) is known to be critically involved in rodent lung development, homeostasis, and injury/repair. However, there is lack of information on their presence and function in the human lung. Based on a number of morphological (lipid staining), molecular (presence of characteristic lipogenic and absence of myogenic markers), and functional (triglyceride uptake) characteristics that are the hallmarks of the rodent lung lipofibroblast, using human lung fibroblasts of embryonic (WI-38) and adult origin and lung tissue from human autopsy specimens, the authors for the first time clearly demonstrate the presence of lipofibroblasts in the human lung. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that in vitro nicotine exposure disrupts specific epithelial-mesenchymal paracrine signaling pathways and results in pulmonary interstitial lipofibroblast (LIF)-to-myofibroblast (MYF) transdifferentiation, resulting in altered pulmonary development and function. Studies were done to determine whether nicotine induces LIF-to-MYF transdifferentiation and to elucidate underlying molecular mechanism(s) involved and to determine whether nicotine-induced LIF-to-MYF transdifferentiation could be prevented by stimulating specific alveolar interstitial fibroblast lipogenic pathway. WI38 cells, a human embryonic pulmonary fibroblast cell line, were treated with nicotine with or without specific agonists of alveolar fibroblast lipogenic pathway, PTHrP, DBcAMP, or the potent PPARγ, stimulant rosiglitazone (RGZ) for 7 days. Expression of key lipogenic and myogenic markers was examined by RT-PCR, Western hybridization, and immunohistochemistry. The effect of nicotine on triglyceride uptake by WI38 cells and PTHrP binding to its receptor was also determined. Finally, the effect of transfecting WI38 cells with a PPARγ expression vector on nicotine-induced LIF-to-MYF transdifferentiation was determined. Nicotine treatment resulted in significantly decreased expression of lipogenic and increased expression of myogenic markers in a dose-dependent manner, indicating nicotine-induced LIF-to-MYF transdifferentiation. This was accompanied by decreased PTHrP receptor binding to its receptor. The nicotine-induced LIF-to-MYF transdifferentiation was completely prevented by concomitant treatment with PTHrP, DBcAMP, RGZ, and by transiently overexpressing PPARγ. Our data suggest nicotine induces alveolar LIF-to-MYF transdifferentiation through a mechanism involving downregulation of lipogenic PTHrP-mediated, cAMP-dependent PKA signaling pathway, which can be prevented using specific molecular targets. Potential therapeutic implications of these observations against in utero nicotine-induced lung injury remain to be tested. [ABSTRACT FROM AUTHOR]

Objectives: The optimal method for epinephrine administration during neonatal resuscitation is not known. We hypothesized that epinephrine will be delivered more efficiently when administered via a feeding catheter inserted into the endotracheal tube (G-ETT) vs when administered directly into the ETT (D-ETT). Our objectives were to (1) compare the delivery of epinephrine to the distal end of the ETT when administered via D-ETT vs G-ETT; (2) measure the retention of epinephrine within the ETT vs the feeding catheter used for the drug delivery; and (3) compare the delivery of the drug with and without an air flush after administration via C-ETT. Methods: All experiments were performed in vitro, simulating epinephrine administration during neonatal resuscitation, according to the standard guidelines,. Radiolabeled epinephrine, diluted to 1 &mi;Ci/ml, was used and experiments were repeated at least 4 times. Epinephrine administration via D-ETT was followed by one manual breath via a self-inflating bag attached to the ETT. Epinephrine delivery via G-ETT was followed by 1 ml saline flush, and in some experiments, this was also followed by a 1 cm³ air flush. Epinephrine delivery and retention were assessed by measuring the radioactive content of the efficient fluid and that of the ETT or of the feeding catheter used drug delivery. Results: Significantly higher dosage of the drug was delivered when administered via D-ETT vs C-ETT, if air flush following the saline flush after the drug instillation, there was no difference in the amount of epinephrine delivered between the two methods. Retention in the ETT wall or the catheter was < 7.5% of the administered dose with either method. Conclusion: Without an air flush following G-ETT method of epinephrine delivery, higher dosage of the drug is delivered via D-ETT vs G-ETT method. An air flush following the saline flush during G-ETT method improves drug delivery. Given that the G-ETT method is more cumbersome and time consuming, and does not improve drug delivery, D-ETT administration should be the method of choice for epinephrine delivery during neonatal resuscitation. [ABSTRACT FROM AUTHOR]

Investigates the influence of maternal diabetes on the outcome of very-low-birth-weigh infants (VLBWI) born in Winnipeg, Manitoba. Comparison of mortality rates of VLBWI born to mothers with and without diabetes; Assessment of diabetes mellitus by conventional criteria; Variables indicating infant condition at birth.

Pulmonary alveolar type II cells have been shown to be a possible target for the secosteroid hormone, 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], during perinatal transition. At present, there is great interest to isolate and identify the metabolites of 1α,25(OH)2D3 produced in its target tissues and to determine the contribution of each individual metabolite of 1α,25(OH)2D3 to the final expression of the pleiotropic actions attributed to 1α,25(OH)2D3. Of all the known metabolites of 1α,25(OH)2D3, 1α,25(OH)2-3-epi-D3 has gained most attention as it is produced only in specific tissues and possesses significant activity in tissues in which it is produced. Furthermore, in vivo studies indicate that this metabolite when compared to 1α,25(OH)2D3 is less calcemic. Therefore, we performed the present study to identify production of 1α,25(OH)2-3-epi-D3 in alveolar type II cells, and to evaluate its effect on surfactant synthesis. We incubated NCI-H441 cells, an alveolar type II cell line, with 1α,25(OH)2D3 and demonstrated that these cells metabolize 1α,25(OH)2D3 to various previously well-characterized polar metabolites, and to a less polar metabolite which was unequivocally identified as 1α,25(OH)2-3-epi-D3 by GC/MS and HPLC analysis. Further, biological activity studies in H441 cells indicated that 1α,25(OH)2-3-epi-D3 possesses significant activity in terms of its ability: (i) to increase surfactant phospholipid synthesis, (ii) to induce surfactant SP-B mRNA gene expression, and (iii) to increase surfactant SP-B protein synthesis. However, the activity of 1α,25(OH)2-3-epi-D3 when compared to 1α,25(OH)2D3 in generating VDR-mediated transcriptional activity in ROS 17/2.8 cells transfected with human osteocalcin VDRE/growth hormone gene construct, was significantly reduced. The high metabolic stability of 1α,25(OH)2-3-epi-D3, as previously proposed by us, may be a possible explanation for the high in vitro activity in spite of the reduced VDR-mediated transcriptional activity. In summary, we report for the first time the pathways of 1α,25(OH)2D3 metabolism in pulmonary alveolar type II cells and indicate that 1α,25(OH)2-3-epi-D3, a natural intermediary metabolite of 1α,25(OH)2D3 possesses significant activity in stimulating surfactant synthesis in alveolar type II cells. [Copyright &y& Elsevier]

OBJECTIVE: The use of continuous positive airway pressure (CPAP) in the treatment of a variety of neonatal respiratory conditions is associated with improvement in arterial oxygen saturation, decreased long-term morbidity, and an overall improvement in infant survival. We reasoned that CPAP might change diaphragm length by increasing end-expiratory lung volume (EEV), but the extent to which this occurs has not been assessed. This study was designed to evaluate (1) the extent to which CPAP shortens the diaphragm and (2) the relationship of diaphragm thickness and excursion with arterial oxygen saturation in spontaneously breathing preterm infants. STUDY DESIGN: Ultrasonographically (7.5 MHz transducer), diaphragm thickness and diaphragm excursion were measured in 12 stable preterm infants [birth weight 1120 ± 225 g (mean ± SD); study weight 1187 ± 400 g; gestational age 29 ± 1 week; postnatal age 10 ± 8 days, six males and six females] at three levels of CPAP [1-3, 4-6, and 7-9 cm H[SUB2]O (low, medium, and high, respectively)]. Heart rate, respiratory rate, and arterial oxygen saturation were simultaneously recorded. RESULTS: We found that diaphragm thickness and arterial oxygen saturation increased, and diaphragm excursion decreased significantly at higher levels of CPAP (p < 0.05). The shortening of the diaphragm at the high levels of CPAP, calculated from the increase in diaphragm thickness, was 36% at EEV and 31% at end-inspiratory volume. CONCLUSION: We conclude that the improvement in arterial oxygen saturation with CPAP occurred despite the presence of a shorter and a less mobile diaphragm, and that other physiological and mechanical alterations accompanying the application of CPAP offset its negative effects on diaphragm function. We speculate that with excessive CPAP, however, diaphragm dysfunction along with the previously described adverse hemodynamic effects may outweigh its benefits on oxygenation. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses reports within the issue, including review articles and new studies that cover many aspects of peroxisome proliferator-activated receptors (PPAR) biology and their potential translational implications.

A letter to the editor is presented in response to the article "Evo-Devo and the Lungfish: The Last Gap of Intelligent Design" is presented.

Background: A head to head comparison study on renal function and ductal response between indomethacin and ibuprofen has rarely been conducted in extremely low birth weight (ELBW) infants. Objectives: The aim was to compare renal function and ductal response between indomethacin and ibuprofen in ELBW infants. Methods: We performed a double-blind randomized control trial to compare renal function and ductal response between indomethacin (0.2, 0.1, and 0.1 mg/kg i.v. every 24 h for 3 doses) and ibuprofen lysine (10, 5, and 5 mg/kg i.v. every 24 h for 3 doses) in ELBW infants with significant hemodynamic patent ductus arteriosus (cardiovascular dysfunction score >3 and LA/AO ≥ 1.3). Results: A total of 144 infants were enrolled: 73 received indomethacin and 71 received ibuprofen lysine. Significant decreases in urine output were seen in 30 infants (41%) in the indomethacin group and 15 (21%) in the ibuprofen group (p = 0.02). The indomethacin group was associated with a significantly higher chance of persistent ductal response than the ibuprofen group (66 vs. 49%, p = 0.046), but with a lower glomerular filtration rate on day 1, higher serum creatinine on days 1, 2, and 7, and lower urinary prostaglandin on days 2-7. Both groups were comparable in mortality and in bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and retinopathy of prematurity morbidity. Conclusions: With the current dosage, ibuprofen had fewer renal side effects but was associated with a lower rate of persistent ductal closure in ELBW infants. The precise role of prostaglandin on renal tubular function in ELBW infants remains to be further investigated.ratio [ABSTRACT FROM AUTHOR]

Background: By altering specific developmental signaling pathways that are necessary for fetal lung development, perinatal nicotine exposure affects lung growth and differentiation, resulting in the offsprings' predisposition to childhood asthma; peroxisome proliferator-activated receptor gamma (PPARγ) agonists can inhibit this effect. However, whether the perinatal nicotine-induced asthma risk is restricted to nicotine-exposed offspring only; whether it can be transmitted to the next generation; and whether PPARγ agonists would have any effect on this process are not known.Methods: Time-mated Sprague Dawley rat dams received either placebo or nicotine (1 mg/kg, s.c.), once daily from day 6 of gestation to postnatal day (PND) 21. Following delivery, at PND21, generation 1 (F1) pups were either subjected to pulmonary function tests, or killed to obtain their lungs, tracheas, and gonads to determine the relevant protein markers (mesenchymal contractile proteins), global DNA methylation, histone 3 and 4 acetylation, and for tracheal tension studies. Some F1 animals were used as breeders to generate F2 pups, but without any exposure to nicotine in the F1 pregnancy. At PND21, F2 pups underwent studies similar to those performed on F1 pups.Results: Consistent with the asthma phenotype, nicotine affected lung function in both male and female F1 and F2 offspring (maximal 250% increase in total respiratory system resistance, and 84% maximal decrease in dynamic compliance following methacholine challenge; P < 0.01, nicotine versus control; P < 0.05, males versus females; and P > 0.05, F1 versus F2), but only affected tracheal constriction in males (51% maximal increase in tracheal constriction following acetylcholine challenge, P < 0.01, nicotine versus control; P < 0.0001, males versus females; P > 0.05, F1 versus F2); nicotine also increased the contractile protein content of whole lung (180% increase in fibronectin protein levels, P < 0.01, nicotine versus control, and P < 0.05, males versus females) and isolated lung fibroblasts (for example, 45% increase in fibronectin protein levels, P < 0.05, nicotine versus control), along with decreased PPARγ expression (30% decrease, P < 0.05, nicotine versus control), but only affected contractile proteins in the male trachea (P < 0.05, nicotine versus control, and P < 0.0001, males versus females). All of the nicotine-induced changes in the lung and gonad DNA methylation and histone 3 and 4 acetylation were normalized by the PPARγ agonist rosiglitazone except for the histone 4 acetylation in the lung.Conclusions: Germline epigenetic marks imposed by exposure to nicotine during pregnancy can become permanently programmed and transferred through the germline to subsequent generations, a ground-breaking finding that shifts the current asthma paradigm, opening up many new avenues to explore. [ABSTRACT FROM AUTHOR]

In a rat model, downregulation of homeostatic mesenchymal peroxisome proliferator-activated receptor-β (PPAR-β) signaling following perinatal nicotine exposure contributes to offspring asthma, which can be effectively prevented by concomitant administration of PPAR-β agonist rosiglitazone (RGZ). However, whether perinatal nicotine exposure- induced asthma can be reversed is not known. We hypothesized that perinatal nicotine exposure-induced asthma would be reversed by PPAR-β agonist RGZ. Pregnant rat dams received either placebo or nicotine from embryonic day 6 until term. Following spontaneous delivery at term, dams were continued on the assigned treatments, up to postnatal day 21 (PND21). However, at delivery, pups were divided into two groups; one group received placebo, and the other group received RGZ from PND1 to PND21. At PND21, pulmonary function and the expression of mesenchymal markers of airway contractility (α-smooth muscle actin, calponin, fibronectin, collagen I, and collagen III) were determined by immunoblotting and immunostaining for the evidence of reversibility of perinatal nicotine exposure-induced lung effects. Compared with controls, perinatal nicotine exposure caused 1) a significant increase in airway resistance and a decrease in airway compliance following methacholine challenge, 2) a significant increase in acetylcholine-induced tracheal constriction, and 3) increased pulmonary and tracheal expression of the mesenchymal markers of contractility. Treatment with RGZ, starting on PND1, reversed all of the nicotine-induced molecular and functional pulmonary effects, virtually normalizing the pulmonary phenotype of the treated animals. We conclude that perinatal nicotine exposure-induced functional and molecular alterations in upper and lower airways can be reversed by PPAR-β agonist RGZ, allowing an effective intervention even when started postnatally. [ABSTRACT FROM AUTHOR]

Perinatal nicotine exposure via tobacco smoking results in increased proclivity to chronic lung disease (CLD); however, the underlying molecular mechanisms remain incompletely understood. We previously demonstrated that in addition to nicotine's direct effects on the developing lung, there are also adverse molecular alterations in bone marrow-derived mesenchymal stem cells (BMSCs), which are vital to lung injury repair. Whether perinatal nicotine exposure via electronic-cigarette (e-cig) vaping also adversely affects BMSCs is unknown. This is highly relevant due to marked increase in e-cig vaping including by pregnant women. Hypothesizing that perinatal nicotine exposure via e-cig vaping predisposes BMSCs to a pro-myofibroblastic phenotype, pregnant rat dams were exposed to fresh air (control), vehicle (e-cig without nicotine), or e-cig (e-cig with nicotine) daily during pregnancy and lactation. At postnatal day 21, offspring BMSCs were isolated and studied for cell proliferation, migration, wound healing response, and expression of key Wnt and PPARγ signaling intermediates (β-catenin, LEF-1, PPARγ, ADRP and C/EBPα) and myogenic markers (fibronectin, αSMA, calponin) proteins using immunoblotting. Compared to controls, perinatal e-cig exposure resulted in significant decrease in BMSC proliferation, migration, and wound healing response. The expression of key Wnt signaling intermediates (β-catenin, LEF-1) and myogenic markers (fibronectin, αSMA, calponin) increased significantly, while PPARγ signaling intermediates (PPARγ, ADRP, and C/EBPα) decreased significantly. Based on these data, we conclude that perinatally e-cig exposed BMSCs demonstrate pro-myofibroblastic phenotype and impaired injury-repair potential, indicating a potentially similar susceptibility to CLD following perinatal nicotine exposure via vaping as seen following parenteral perinatal nicotine exposure. • E-cig exposure during pregnancy affects bone marrow stem cells (BMSCs) adversely. • Exposure leads to decreased BMSC proliferation, migration, and wound healing. • Wnt signaling and myogenic markers increase, while PPARγ signaling decreases. • Perinatal e-cig vaping increases offspring's lung injury risk, like traditional cigs. [ABSTRACT FROM AUTHOR]

The transition from uni- to multicellular organisms required metabolic cooperativity through cell-cell interactions mediated by soluble growth factors. We have empirically demonstrated such an integrating mechanism by which the metabolic hormone leptin stimulates lung development, causing the thinning of the gas exchange surface and the obligate increase in lung surfactant synthesis. All of these processes have occurred both phylogenetically and developmentally during the course of vertebrate lung evolution from fish to man. Here we show the integrating effects of the environmentally sensitive, pleiotropic hormone leptin on the development of the Xenopus laevis tadpole lung. The process described in this study provides a mechanistically integrated link between the metabolic regulatory hormone leptin and its manifold downstream effects on a wide variety of physiologic structures and functions, including locomotion and respiration, the cornerstones of land vertebrate evolution. It provides physiologic selection pressure at multiple levels to progressively generate Gene Regulatory Networks both within and between organs, from cells to systems. This model provides a cipher for understanding the evolution of complex physiology. [ABSTRACT FROM AUTHOR]

Despite tremendous advances in neonatology, bronchopulmonary dysplasia (BPD) remains a major cause of morbidity and mortality among premature infants. Any intervention that would reduce the risk of BPD or improve its outcome is likely to have substantial clinical and financial benefits. However, there is a clear lack of an effective agent for the treatment and/or prevention of BPD. This is due to an incomplete understanding of the molecular mechanisms involved in its pathogenesis. Taking a basic biological approach, our laboratory has discovered that disruption of normal alveolar homeostatic signaling is centrally involved in this process. Using a number of in vitro and in vivo models, our laboratory has demonstrated that stabilization of the normal alveolar homeostatic signaling pathway(s) can prevent and/or rescue the molecular injuries caused by the insults that lead to BPD. Here, we review the existing approaches to prevent and treat BPD and then, based on our insights into the pathogenesis of BPD, we propose novel and innovative therapeutic options that impact the disease on a cell/molecular level, unlike most of the current treatments available for BPD. [ABSTRACT FROM AUTHOR]

Perinatal smoke/nicotine exposure alters lung development and causes asthma in exposed offspring, transmitted transgenerationally. The mechanism underlying the transgenerational inheritance of perinatal smoke/nicotine‐induced asthma remains unknown, but germline epigenetic modulations may play a role. Using a well‐established rat model of perinatal nicotine‐induced asthma, we determined the DNA methylation pattern of spermatozoa of F1 rats exposed perinatally to nicotine in F0 gestation. To identify differentially methylated regions (DMRs), reduced representation bisulfite sequencing was performed on spermatozoa of F1 litters. The top regulated gene body and promoter DMRs were tested for lung gene expression levels, and key proteins involved in lung development and repair were determined. The overall CpG methylation in F1 sperms across gene bodies, promoters, 5′‐UTRs, exons, introns, and 3′‐UTRs was not affected by nicotine exposure. However, the methylation levels were different between the different genomic regions. Eighty one CpG sites, 16 gene bodies, and 3 promoter regions were differentially methylated. Gene enrichment analysis of DMRs revealed pathways involved in oxidative stress, nicotine response, alveolar and brain development, and cellular signaling. Among the DMRs, Dio1 and Nmu were the most hypermethylated and hypomethylated genes, respectively. Gene expression analysis showed that the mRNA expression and DNA methylation were incongruous. Key proteins involved in lung development and repair were significantly different (FDR < 0.05) between the nicotine and placebo‐treated groups. Our data show that DNA methylation is remodeled in offspring spermatozoa upon perinatal nicotine exposure. These epigenetic alterations may play a role in transgenerational inheritance of perinatal smoke/nicotine induced asthma. [ABSTRACT FROM AUTHOR]

Intrauterine growth restriction (IUGR) leads to offspring obesity. In a maternal food restriction (MFR) during pregnancy‐related IUGR rat model, bone marrow stem cells showed enhanced adipogenic programming; however, the effect of IUGR on white adipose tissue (WAT) progenitors is unknown. Here, by mRNA and functional profiling, we determined sex‐specific adipogenic programming of WAT progenitors isolated from pups on the postnatal day (PND) 1 and 21. On PND1, PPARγ and Pref‐1 expression was significantly downregulated in preadipocytes of both MFR males and females; however, at PND21, preadipocytes of MFR males showed upregulation in these genes. Even following adipogenic induction, both male and female MFR adipocytes exhibited lower PPARγ, ADRP, and adiponectin levels at PND1; however, at PND21 MFR male adipocytes showed an upward trend in the expression of these genes. An adipogenesis‐specific RT‐PCR array showed that male MFR adipocytes were programmed to exhibit stronger adipogenic propensity than females. Last, serum sex hormone and adipocyte estrogen/testosterone receptor expression profiles provide preliminary insights into the possible mechanism underlying sex‐specific adipogenic programming in the IUGR offspring. In summary, IUGR programs WAT preadipocytes to greater adipogenic potential in males. Although the altered adipogenic programming following MFR was detectable at PND1, the changes were more pronounced at PND21, suggesting a potential role of postnatal nutrition in facilitating the sex‐specific adipogenic programming in the IUGR offspring. [ABSTRACT FROM AUTHOR]

In a rat model, perinatal nicotine exposure results in an epigenetically driven multi- and trans-generationally transmitted asthmatic phenotype that tends to wane over successive generations. However, the effect of repeat nicotine exposure during the F1 (Filial 1) gestational period on the transmitted phenotype is unknown. Using a well-established rat model, we compared lung function, mesenchymal markers of airway reactivity, and global gonadal DNA methylation changes in F2 offspring in a sex-specific manner following perinatal exposure to nicotine in only the F0 gestation, in both F0 and F1 (F0/F1) gestations, and in neither (control group). Both F0 only and F0/F1 exposure groups showed an asthmatic phenotype, an effect that was more pronounced in the F0/F1 exposure group, especially in males. Testicular global DNA methylation increased, while ovarian global DNA methylation decreased in the F0/F1 exposed group. Since the offspring of smokers are more likely to smoke than the offspring of nonsmokers, this sets the stage for more severe asthma if both mother and grandmother had smoked during their pregnancies. Increased gonadal DNA methylation changes following nicotine reexposure in the F1 generation suggests that epigenetic mechanisms might well underlie the transgenerational inheritance of acquired phenotypic traits in general and nicotine-induced asthma in particular. [ABSTRACT FROM AUTHOR]

Although increased predisposition to cardiac fibrosis and cardiac dysfunction has been demonstrated in the perinatally nicotine-exposed heart, the underlying mechanisms remain unclear. With the use of a well-established rat model and cultured primary neonatal rat cardiac fibroblasts, the effect of perinatal nicotine exposure on offspring heart extracellular matrix deposition and the likely underlying mechanisms were investigated. Perinatal nicotine exposure resulted in increased collagen type I (COL1A1) and III (COL3A1) deposition along with a decrease in miR-29 family and an increase in long noncoding RNA myocardial infarction-associated transcript (MIAT) levels in offspring heart. Nicotine treatment of isolated primary neonatal rat cardiac fibroblasts suggested that these effects were mediated via nicotinic acetylcholine receptors including ±7 and the induced collagens accumulation was reversed by a gain-of function of miR-29 family. Knockdown of MIAT resulted in increased miR-29 family and decreased COL1A1 and COL3A1 levels, suggesting nicotine-mediated MIAT induction as the underlying mechanism for nicotine-induced collagen deposition. Luciferase reporter assay and RNA immunoprecipitation studies showed an intense physical interaction between MIAT, miR-29 family, and argonaute 2, corroborating the mechanistic link between perinatal nicotine exposure and increased extracellular matrix deposition. Overall, perinatal nicotine exposure resulted in lower miR-29 family levels in offspring heart, while it elevated cardiac MIAT and collagen type I and III levels. These findings provide mechanistic basis for cardiac dysfunction in perinatal nicotine- exposed offspring and offer multiple novel potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Prevention of bronchopulmonary dysplasia (BPD) in premature-birth babies continues to be an unmet medical need. Intramuscular vitamin A is currently employed in preterm neonates to prevent BPD but requires intramuscular injections in fragile neonates. We hypothesized that noninvasive inhaled delivery of vitamin A, targeted to lung, would be a more effective and tolerable strategy. We employed our well-established hyperoxia-injury neonatal rat model, exposing newborn rats to 7 days of constant extreme (95% O2) hyperoxia, comparing vitamin A dosed every 48 h via either aerosol inhalation or intramuscular injection with normoxic untreated healthy animals and vehicle-inhalation hyperoxia groups as positive and negative controls, respectively. Separately, similar vitamin A dosing of normoxia-dwelling animals was performed. Analyses after day 7 included characterization of alveolar histomorphology and protein biomarkers of alveolar maturation [surfactant protein C (SP-C), peroxisome proliferator-activated receptor (PPAR) γ, cholinephosphate cytidylyl transferase, vascular endothelial growth factor and its receptor, FLK-1, and retinoid X receptors (RXR-α, -β, and -γ], apoptosis (Bcl2 and Bax) key injury repair pathway data including protein markers (ALK-5 and β-catenin) and neutrophil infiltration, and serum vitamin A levels. Compared with intramuscular dosing, inhaled vitamin A significantly enhanced biomarkers of alveolar maturation, mitigated hyperoxia-induced lung damage, and enhanced surfactant protein levels, suggesting that it may be more efficacious in preventing BPD in extremely premature infants than the traditionally used IM dosing regimen. We speculate lung-targeted inhaled vitamin A may also be an effective therapy against other lung damaging conditions leading to BPD or, more generally, to acute lung injury. [ABSTRACT FROM AUTHOR]

Antenatal steroids (ANS) accelerate fetal lung maturation and reduce the incidence of respiratory distress syndrome. However, sex specificity, i.e., being less effective in males, and potential long-term neurodevelopmental sequelae, particularly with repeated courses, remain significant limitations. The differential sex response to ANS is likely mediated via the inhibitory effect of fetal androgens on steroid’s stimulatory effect on alveolar epithelial-mesenchymal interactions. Since peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists accelerate lung maturation by stimulating alveolar epithelial-mesenchymal interactions, independent of fetal sex, we hypothesized that the effect of PPAR-γ agonist pioglitazone (PGZ) would be sex-independent. Pregnant Sprague-Dawley rat dams were intraperitoneally administered dexamethasone (DEX) or PGZ on embryonic day (e) 18 and e19. At e20, pups were delivered by cesarean section, and fetal lungs and brains were examined for markers of lung maturation and apoptosis, respectively. Mixed epithelial-fibroblast cell cultures were examined to gain mechanistic insights. Antenatal PGZ increased alveolar epithelial and mesenchymal maturation markers equally in males and females; in contrast, antenatal DEX had sex-specific effects. Additionally, unlike DEX, antenatal PGZ did not increase hippocampal apoptosis. We conclude that PPAR-γ agonist administration is an effective, and probably even a superior, alternative to ANS for accelerating fetal lung maturity equally in both males and females. [ABSTRACT FROM AUTHOR]

N-myristoyltransferase-1 (NMT1) catalyzes protein myristoylation, a lipid modification that is elevated in cancer cells. NMT1 sustains proliferation and/or survival of cancer cells through mechanisms that are not completely understood. We used genetic and pharmacological inhibition of NMT1 to further dissect the role of this enzyme in cancer, and found an unexpected essential role for NMT1 at promoting lysosomal metabolic functions. Lysosomes mediate enzymatic degradation of vesicle cargo, and also serve as functional platforms for mTORC1 activation. We show that NMT1 is required for both lysosomal functions in cancer cells. Inhibition of NMT1 impaired lysosomal degradation leading to autophagy flux blockade, and simultaneously caused the dissociation of mTOR from the surface of lysosomes leading to decreased mTORC1 activation. The regulation of lysosomal metabolic functions by NMT1 was largely mediated through the lysosomal adaptor LAMTOR1. Accordingly, genetic targeting of LAMTOR1 recapitulated most of the lysosomal defects of targeting NMT1, including defective lysosomal degradation. Pharmacological inhibition of NMT1 reduced tumor growth, and tumors from treated animals had increased apoptosis and displayed markers of lysosomal dysfunction. Our findings suggest that compounds targeting NMT1 may have therapeutic benefit in cancer by preventing mTORC1 activation and simultaneously blocking lysosomal degradation, leading to cancer cell death. [ABSTRACT FROM AUTHOR]

Introduction. Environmental exposure of the developing offspring to cigarette smoke or nicotine is an important predisposing factor for many chronic respiratory conditions, such as asthma, emphysema, pulmonary fibrosis, and so forth, in the exposed offspring. Studies showed that electroacupuncture (EA) applied to maternal "Zusanli" (ST36) acupoints during pregnancy and lactation protects against perinatal nicotine exposure- (PNE-) induced lung damage. However, the most effective time period, that is, prenatal vs. postnatal, to attain this effect has not been determined. Objective. To determine the most effective developmental timing of EA's protective effect against PNE-induced lung phenotype in the exposed offspring. Methods. Pregnant rats were given (1) saline ("S" group); (2) nicotine ("N" group); (3) nicotine + EA, exclusively prenatally ("Pre-EA" group); (4) nicotine + EA, exclusively postnatally ("Post-EA," group); and (5) nicotine + EA, administered both prenatally and postnatally ("Pre- and Post-EA" group). Nicotine was injected once daily (1 mg/kg, 100 μl) and EA was administered to bilateral ST36 acupoints once daily during the specified time-periods. At the end of the experimental periods, key hypothalamic pituitary adrenal (HPA) axis markers in pups and dams, and lung function, morphometry, and the central molecular markers of lung development in the offspring were determined. Results. After nicotine exposure, alveolar mean linear intercept (MLI) increased, but mean alveolar number (MAN) decreased and lung PPARγ level decreased, but glucocorticoid receptor (GR) and serum corticosterone (Cort) levels increased, in line with the known PNE-induced lung phenotype. In the nicotine exposed group, maternal hypothalamic corticotropin releasing hormone (CRH) level decreased, but pituitary adrenocorticotropic hormone (ACTH) and serum Cort levels increased. In the "Pre- and Post-EA" groups, PNE-induced alterations in lung morphometry, lung development markers, and HPA axis were blocked. In the "Pre-EA" group, PNE-induced changes in lung morphometry, GR, and maternal HPA axis improved; lung PPARγ and serum Cort levels were slightly but not significantly improved. In contrast, the exclusive "Post-EA" group showed none of these benefits. Conclusions. Maternal EA applied to ST36 acupoints during both pre- and postnatal periods preserves offspring lung structure and function despite perinatal exposure to nicotine. EA applied during the "prenatal period" affords only limited benefits, whereas EA applied during the "postnatal period" is ineffective, suggesting that the EA's effects in modulating PNE-induced lung phenotype are limited to specific time-periods during lung development. [ABSTRACT FROM AUTHOR]

Background. Maternal smoking and/or exposure to environmental tobacco smoke continue to be significant factors in fetal and childhood morbidity and are a serious public health issue worldwide. Nicotine passes through the placenta easily with minimal biotransformation, entering fetal circulation, where it results in many harmful effects on the developing offspring, especially on the developing respiratory system. Objectives. Recently, in a rat model, electroacupuncture (EA) at maternal acupoints ST 36 has been shown to block perinatal nicotine-induced pulmonary damage; however, the underlying mechanism and the specificity of ST 36 acupoints for this effect are unknown. Here, we tested the hypothesis that compared with EA at ST 36, EA at LU 5 acupoints, which are on lung-specific meridian, will be equally or more effective in preventing perinatal nicotine-induced pulmonary changes. Methods. Twenty-four pregnant rat dams were randomly divided into 4 groups: saline ("S"), nicotine ("N"), nicotine + ST 36 (N + ST 36), and nicotine + LU 5 (N + LU 5) groups. Nicotine (1 mg/kg, subcutaneously) and EA (at ST 36 or LU 5 acupoints, bilaterally) were administered from embryonic day 6 to postnatal day 21 once daily. The "S" group was injected saline. As needed, using ELISA, western analysis, q-RT-PCR, lung histopathology, maternal and offspring hypothalamic pituitary adrenal axes, offspring key lung developmental markers, and lung morphometry were determined. Results. With nicotine exposure, alveolar count decreased, but mean linear intercept and septal thickness increased. It also led to a decrease in pulmonary function and PPARγ and an increase of β-catenin and glucocorticoid receptor expression in lung tissue and corticosterone in the serum of offspring rats. Electroacupuncture at ST 36 normalized all of these changes, whereas EA at LU 5 had no obvious effect. Conclusion. Electroacupuncture applied to ST 36 acupoints provided effective protection against perinatal nicotine-induced lung changes, whereas EA applied at LU 5 acupoints was ineffective, suggesting mechanistic specificity and HPA axis' involvement in mediating EA at ST 36 acupoints' effects in mitigating perinatal nicotine-induced pulmonary phenotype. This opens the possibility that other acupoints, besides ST 36, can have similar or even more robust beneficial effects on the developing lung against the harmful effect of perinatal nicotine exposure. The approach proposed by us is simple, cheap, quick, easy to administer, and is devoid of any significant side effects. [ABSTRACT FROM AUTHOR]

Nicotine inhalation via electronic cigarettes (e‐cigs) is an emerging concern. However, little is known about the acute toxicity in the lungs following inhalation of nicotine‐containing e‐cig aerosols. We hypothesized that acute exposure to aerosolized nicotine causes lung toxicity by eliciting inflammatory and dysregulated repair responses. Adult C57BL/6J mice were exposed 2 hours daily for 3 days to e‐cig aerosols containing propylene glycol (PG) with or without nicotine. Acute exposure to nicotine‐containing e‐cig aerosols induced inflammatory cell influx (neutrophils and CD8a+ T lymphocytes), and release of pro‐inflammatory cytokines in bronchoalveolar lavage fluid in a sex‐dependent manner. Inhalation of e‐cig aerosol containing PG alone significantly augmented the lung levels of various homeostasis/repair mediators (PPARγ, ADRP, ACTA2, CTNNB1, LEF1, β‐catenin, E‐cadherin, and MMP2) in a sex‐dependent manner when compared to air controls. These findings were accompanied by an increase in protein abundance and altered gene expression of lipogenic markers (PPARγ, ADRP) and myogenic markers (fibronectin, α‐smooth muscle actin and β‐catenin), suggesting a dysregulated repair response in mouse lungs. Furthermore, exposure to nicotine‐containing e‐cig aerosols or PG alone differentially affected the release of pro‐inflammatory cytokines in healthy and COPD human 3D EpiAirway tissues. Overall, acute exposure to nicotine‐containing e‐cig aerosols was sufficient to elicit a pro‐inflammatory response and altered mRNA and protein levels of myogenic, lipogenic, and extracellular matrix markers in mouse lung in a sex‐dependent manner. Thus, acute exposure to inhaled nicotine via e‐cig leads to dysregulated repair and inflammatory responses, which may lead to airway remodeling in the lungs. [ABSTRACT FROM AUTHOR]

Many factors during pregnancy can induce intrauterine growth restriction (IUGR), resulting in various adverse perinatal outcomes such as low birth weight and multiple organ disorders. Among these factors, prenatal smoke/nicotine exposure is a common cause of IUGR, often associated with altered fetal lung development. The classical Wnt signaling pathway plays a vital role in lung development, and its alterations are commonly associated with developmental lung pathologies. The purpose of this study was to determine whether electroacupuncture (EA) at "Zusanli" (ST 36) points protects perinatal nicotine exposure (PNE)-induced offspring lung dysplasia through Wnt/β-catenin signaling pathway and to identify specific Wnt signaling pathway targets of EA. Following a well-established protocol, nicotine (1 mg/kg/ body weight) was administered subcutaneously to pregnant Sprague Dawley rat dams from gestational day 6 to postnatal day 21. In the EA group, dams were treated with EA at both ST 36 acupoints, while in another experimental group, Wnt/β-catenin signaling pathway agonist was injected subcutaneously (2 mg/kg/ body weight). Offspring body weight (PND 1, 7, 14, and 21), lung weight, Wnt signaling markers, pulmonary function, and lung morphology were determined at sacrifice on PND 21. Specifically, Western blotting and Real-time PCR were used to detect the protein and mRNA levels of critical Wnt signaling markers Wnt2, Wnt7b, FZD4, FZD7, LRP5, and LRP6 in the offspring lung. The protein levels of β-catenin in lung tissue of offspring rats were detected by ELISA that of LEF-1 by Western blotting. Compared to the control group, the body and lung weights of the offspring rats were significantly decreased in the nicotine-only exposed group. The pulmonary function determined as FVC, PEF, TV, and Cdyn was also significantly decreased, while PIF was significantly increased. The protein levels and mRNA expression of Wnt2, Wnt7b, FZD4, FZD7, LRP5, and LRP6 in the lung tissue of the PNE offspring rats were significantly increased. With EA administration at ST 36 acupoints concomitant with nicotine administration, the body and lung weights, pulmonary function (FVC, PEF, PIF, TV, and Cdyn), protein and mRNA levels Wnt signaling pathway markers (Wnt2, Wnt7b, FZD4, FZD7, LRP5, LRP6, β-catenin, and LEF-1) normalized and were not different from the control group. Notably, Wnt agonists agonist administration blocked the protective effects of EA against PNE-induced lung morphological, molecular, and function changes, highlighting the central significance of Wnt pathway signaling in PNE-induced offspring pulmonary pathology and its modulation by EA at ST 36 acupoints. Concomitant maternal EA at ST 36 acupoints from gestational day 6 to PND 21 protects against offspring PNE-induced lung phenotype. The protective effect is achieved by regulating the expression of Wnt ligand proteins (Wnt2 and Wnt7b) and receptor proteins (FZD4, FZD7, LRP5, and LRP6) upstream of the Wnt/β-catenin signaling pathway intermediates β-catenin, and LEF-1. [Display omitted] • PNE-induced structural, molecular, and functional changes in the offspring lung. • Maternal EA at ST 36 acupoint prevented pulmonary phenotype in PNE offspring rats. • The protective effect of EA is mainly mediated through the Wnt/β-catenin pathway. • EA normalized the upregulated expression of Wnt ligands/receptors in offspring lung. [ABSTRACT FROM AUTHOR]

Perinatal nicotine exposure drives the differentiation of alveolar lipofibroblasts (LIFs), which are critical for lung injury repair, to myofibroblasts (MYFs), which are the hallmark of chronic lung disease. Bone marrow-derived mesenchymal stem cells (BMSCs) are important players in lung injury repair; however, how these cells are affected with perinatal nicotine exposure and whether these can be preferentially driven to a lipofibroblastic phenotype are not known. We hypothesized that perinatal nicotine exposure would block offspring BMSCs lipogenic differentiation, driving these cells toward a MYF phenotype. Since peroxisome proliferator activated-receptor γ (PPARγ) agonists can prevent nicotine-induced MYF differentiation of LIFs, we further hypothesized that the modulation of PPARγ expression would inhibit nicotine's myogenic effect on BMSCs. Sprague Dawley dams were perinatally administered nicotine (1 mg/kg bodyweight) with or without the potent PPARγ agonist rosiglitazone (RGZ), both administered subcutaneously. At postnatal day 21, BMSCs were isolated and characterized morphologically, molecularly, and functionally for their lipogenic and myogenic potentials. Perinatal nicotine exposure resulted in decreased oil red O staining, triolein uptake, expression of PPARγ, and its downstream target gene adipocyte differentiation-related protein by BMSCs, but enhanced α-smooth muscle actin and fibronectin expression, and activated Wnt signaling, all features indicative of their inhibited lipogenic, but enhanced myogenic potential. Importantly, concomitant treatment with RGZ virtually blocked all of these nicotine-induced morphologic, molecular, and functional changes. Based on these data, we conclude that BMSCs can be directionally induced to differentiate into the lipofibroblastic phenotype, and PPARγ agonists can effectively block perinatal nicotine-induced MYF transdifferentiation, suggesting a possible molecular therapeutic approach to augment BMSC's lung injury/repair potential. [ABSTRACT FROM AUTHOR]

Considerable epidemiological and experimental evidence supports the concept that the adult chronic lung disease (CLD), is due, at least in part, to aberrations in early lung development in response to an abnormal intrauterine environment; however, the underlying molecular mechanisms remain unknown. We used a well-established rat model of maternal undernutrition (MUN) during pregnancy that results in offspring intrauterine growth restriction (IUGR) and adult CLD to test the hypothesis that in response to MUN, excess maternal glucocorticoids (GCs) program offspring lung development to a CLD phenotype by altering microRNA (miR)-29 expression, which is a key miR in regulating extracellular matrix (ECM) deposition during development and injury-repair. At postnatal day 21 and 5 mo, compared with the control offspring lung, MUN offspring lung miR-29 expression was significantly decreased in conjunction with an elevated expression of multiple downstream target ECM proteins [collagen (COL)1A1, COL3A1, COL4A5, and elastin], at both mRNA and protein levels. Importantly, MUN-induced changes in miR-29 and target gene expressions were at least partially blocked in the lungs of offspring of MUN dams treated with metyrapone, a selective GC synthesis inhibitor. Furthermore, dexamethasone treatment of cultured fetal rat lung fibroblasts significantly induced miR-29 expression along with the suppression of target ECM proteins. These data, along with the previously known role of miR-29 in regulating ECM deposition in vascular tissue in the MUN offspring, suggest miR-29 to be a common mechanistic denominator for the vascular and pulmonary phenotypes in the IUGR offspring, providing a novel potential therapeutic target. [ABSTRACT FROM AUTHOR]

Abstract Perinatal nicotine exposure can not only lead to lung dysplasia in offspring, but also cause epigenetic changes and induce transgenerational asthma. Previous studies have shown that electro-acupuncture (EA) applied to "Zusanli" (ST 36) can improve the lung morphology and correct abnormal expression of lung development-related protein in perinatal nicotine exposure offspring. However, it is still unclear whether ST 36 has a specific therapeutic effect and how maternal acupuncture can protect the offspring from pulmonary dysplasia. In this study, we compared the different effect of ST 36 and "Fenglong" (ST 40), which belong to the same meridian, in terms of lung pulmonary function and morphology, PPARγ, β-catenin, GR levels in the lung tissues and CORT in the serum of perinatal nicotine exposure offspring, and explored the mechanism of acupuncture based on the maternal hypothalamus-pituitary-adrenal (HPA) axis. It is shown that EA applied to ST 36 could restore the normal function of maternal HPA axis and alleviate maternal glucocorticoid overexposure in offspring, thereby it can up-regulate the PTHrP/PPARγ and down-regulate the Wnt/β-catenin signaling pathways, and protects perinatal nicotine exposure-induced pulmonary dysplasia in offspring. Its effect is better than that of ST 40. These results are of great significance in preventing perinatal nicotine exposure-induced pulmonary dysplasia in offspring. [ABSTRACT FROM AUTHOR]

Background: Despite improvements in perinatal care, bronchopulmonary dysplasia (BPD) in extremely premature infants has not decreased. Postnatal surfactant therapy provides symptomatic relief from respiratory distress syndrome, but does not translate into a reduction in BPD. Therefore, the search for effective interventions to prevent BPD continues. Objectives: Since PPAR-γ agonists have been demonstrated to promote neonatal lung maturation and injury repair, we hypothesized that a formulation of a PPAR-γ agonist, pioglitazone (PGZ) and a synthetic lung surfactant (a surfactant protein B peptide mimic, B-YL) combined would stimulate lung maturation and block hyperoxia-induced neonatal lung injury more effectively than either modality alone. Methods: One-day-old Sprague-Dawley rat pups were administered PGZ + B-YL via nebulization every 24 h for up to 72 h. The pups were exposed to either 21 or 95% O2, and then sacrificed. Their lungs were examined for markers of lung maturation (levels of PPAR-γ, SP-C and choline-phosphate cytidylyltransferase [CCT-α] and [3H]triolein uptake) and injury repair (bronchoalveolar lavage cell count and protein content, and levels of LEF-1, fibronectin, ALK5, and β-catenin) by Western blot analysis. Results: Markers of alveolar epithelial/mesenchymal maturation (PPAR-γ, SP-C, CCT-α, and triolein uptake) increased significantly in the PGZ + B-YL group, more than with either drug alone. Similarly, markers of hyperoxia-induced lung injury were blocked effectively with PGZ + B-YL treatment. Conclusions: Nebulized PPAR-γ agonist PGZ with a synthetic lung surfactant accelerates lung maturation and prevents neonatal hyperoxia-induced lung injury more than either modality alone, with the potential to provide more effective prevention of BPD. [ABSTRACT FROM AUTHOR]

Hyperoxia-induced lung injury is characterized by acute alveolar injury, disrupted epithelial-mesenchymal signaling, oxidative stress, and surfactant dysfunction, yet currently, there is no effective treatment. Although a combination of aerosolized pioglitazone (PGZ) and a synthetic lung surfactant (B-YL peptide, a surfactant protein B mimic) prevents hyperoxia-induced neonatal rat lung injury, whether it is also effective in preventing hyperoxia-induced adult lung injury is unknown. Using adult mice lung explants, we characterize the effects of 24 and 72-h (h) exposure to hyperoxia on 1) perturbations in Wingless/Int (Wnt) and Transforming Growth Factor (TGF)-β signaling pathways, which are critical mediators of lung injury, 2) aberrations of lung homeostasis and injury repair pathways, and 3) whether these hyperoxia-induced aberrations can be blocked by concomitant treatment with PGZ and B-YL combination. Our study reveals that hyperoxia exposure to adult mouse lung explants causes activation of Wnt (upregulation of key Wnt signaling intermediates β-catenin and LEF-1) and TGF-β (upregulation of key TGF-β signaling intermediates TGF-β type I receptor (ALK5) and SMAD 3) signaling pathways accompanied by an upregulation of myogenic proteins (calponin and fibronectin) and inflammatory cytokines (IL-6, IL-1β, and TNFα), and alterations in key endothelial (VEGF-A and its receptor FLT-1, and PECAM-1) markers. All of these changes were largely mitigated by the PGZ + B-YL combination. The effectiveness of the PGZ + B-YL combination in blocking hyperoxia-induced adult mice lung injury ex-vivo is promising to be an effective therapeutic approach for adult lung injury in vivo. [ABSTRACT FROM AUTHOR]

There is increasing concern that early-life exposure to endocrine disruptors affects male offspring reproduction. However, whether di-n-butyl phthalate (DBP), a widely used endocrine disruptor, has transgenerational effects and if so, the exact underlying molecular mechanisms involved remain unknown. In our study, 5 of time-mated pregnant SD rats were exposed to 0 and 500 mg/kg DBP with corn oil as the vehicle via oral gavage from embryonic days (E8-E14). Epigenetic and metabolomic of testis were analyzed after post-natal 60 days. Sperm and testicular cell functions were examined to confirm the transgenerational effects. DBP exposure significantly decreased the sperm counts in F1 through F3 generation. We found distinct metabolic changes in the testis of both F1 and F3 generation offspring, specifically, a significantly increased level of betaine, which is an important methyl donor. In contrast, the expression of betaine homocysteine S-methyltransferase (BHMT), which catalyzes the transfer of methyl moiety from betaine to homocysteine, significantly decreased. There was accompanying global DNA hypomethylation, along with a reduction in follistatin-like 3 (Fstl3) promoter hypomethylation, which is a known modulator of Sertoli cell number and spermatogenesis. In summary, we conclude that metabolomic and epigenetic changes induced by the aberrant expression of BHMT represent a novel mechanism linking in utero DBP exposure to transgenerational spermatogenesis failure. [ABSTRACT FROM AUTHOR]

Introduction: The physiologic vitamin D (VD), 1α,25(OH)D (1,25D) is a local paracrine/autocrine effecter of fetal lung maturation. By stimulating alveolar type II cell and lipofibroblast proliferation and differentiation, parenterally administered 1,25D has been shown to enhance neonatal lung maturation; but due to the potential systemic side effects of the parenteral route, the translational value of these findings might be limited. To minimize the possibility of systemic toxicity, we examined the effects of VD on neonatal lung maturation, when delivered directly to lungs via nebulization. Methods: One-day-old rat pups were administered three different doses of 1,25D and its physiologic precursor 25(OH)D (25D), or the diluent, via nebulization daily for 14 days. Pups were sacrificed for lung, kidneys, and blood collection to determine markers of lung maturation, and serum 25D and calcium levels. Results: Compared to controls, nebulized 25D and 1,25D enhanced lung maturation as evidenced by the increased expression of markers of alveolar epithelial (SP-B, leptin receptor), mesenchymal (PPARγ, C/EBPα), and endothelial (VEGF, FLK-1) differentiation, surfactant phospholipid synthesis, and lung morphology without any significant increases in serum 25D and calcium levels. Conclusions: Inhaled VD is a potentially safe and effective novel strategy to enhance neonatal lung maturation. [ABSTRACT FROM AUTHOR]

Introduction: Pregnant women exposed to tobacco smoke predispose the offspring to many adverse consequences including an altered lung development and function. There is no effective therapeutic intervention to block the effects of smoke exposure on the developing lung. Clinical and animal studies demonstrate that acupuncture can modulate a variety of pathophysiological processes, including those involving the respiratory system; however, whether acupuncture affects the lung damage caused by perinatal smoke exposure is not known. Methods: To determine the effect of acupuncture on perinatal nicotine exposure on the developing lung, pregnant rat dams were administered (1) saline, (2) nicotine, or (3) nicotine + electroacupuncture (EA). Nicotine was administered (1 mg/kg subcutaneously) once a day and EA was applied to both 'Zusanli' (ST 36) points. Both interventions were administered from gestational day 6 to postnatal day 21 (PND21), following which pups were sacrificed. Lungs, blood, and brain were collected to examine markers of lung injury, repair, and hypothalamic pituitary adrenal (HPA) axis. Results: Concomitant EA application blocked nicotine-induced changes in lung morphology, lung peroxisome proliferator-activated receptor γ and wingless-int signaling, two key lung developmental signaling pathways, hypothalamic pituitary adrenal axis (hypothalamic corticotropic releasing hormone and lung glucocorticoid receptor levels), and plasma β-endorphin levels. Conclusions: Electroacupuncture blocks the nicotine-induced changes in lung developmental signaling pathways and the resultant myogenic lung phenotype, known to be present in the affected offspring. We conclude that EA is a promising novel intervention against the smoke exposed lung damage to the developing lung. [ABSTRACT FROM AUTHOR]