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We have previously demonstrated that fetal ethanol exposure deranges the function and viability of the neonatal alveolar macrophage. Although altered differentiation of the alveolar macrophage contributes to pulmonary disease states within the adult lung, the effects of fetal ethanol exposure on the normal differentiation of interstitial to alveolar macrophage in the newborn lung are unknown. In the current study, using a mouse model of fetal ethanol exposure, we hypothesized that altered terminal differentiation of the neonatal interstitial to alveolar macrophage contributes to the observed cellular dysfunction in the ethanol-exposed newborn mouse. Control alveolar macrophage differentiation was characterized by increased expression of CD32/ CDI lb (P [less than or equal to] 0.05) and increased in vitro phagocytosis of Staphylococcus aureus (P [less than or equal to] 0.05) compared with interstitial macrophage. After in utero ethanol exposure, both alveolar and interstitial macrophage lacked the acquisition of CD321CD1 lb (P [less than or equal to] 0.05) and displayed impaired in vitro phagocytosis (P [less than or equal to] 0.05). Ethanol significantly increased transforming growth factor-[[beta].sub.1] (TGF-[[beta].sub.1]) in the bronchoalveolar lavage fluid (P [less than or equal to] 0.05), as well as in both interstitial and alveolar macrophages (P [less than or equal to] 0.05). Oxidant stress contributed to the ethanol-induced changes on the interstitial and alveolar cells, since maternal supplementation with the glutathione precursor S-adenosylmethionine during ethanol ingestion normalized CD32/CD1 lb (P [less than or equal to] 0.05), phagocytosis (P [less than or equal to] 0.05), and TGF-[[beta].sub.1] in the bronchoalveolar lavage fluid and macrophages (P [less than or equal to] 0.05). Contrary to our hypothesis, fetal ethanol exposure did not solely impair interstitial to alveolar macrophage differentiation. Rather, fetal ethanol exposure impaired both neonatal interstitial and alveolar macrophage phagocytic function and differentiation. Increased oxidant stress and elevated TGF-[[beta].sub.1] contributed to the impaired differentiation of both interstitial and alveolar macrophage. alveolar macrophage; fetal alcohol; prematurity; lung doi: 10.1152/ajplung.90609.2008.

We have previously demonstrated that chronic alcohol exposure decreases glutathione in the alveolar space. Although alcohol use is associated with decreased alveolar macrophage function, the mechanism by which alcohol impairs macrophage phagocytosis is unknown. In the current study, we examined the possibility that ethanol-induced alveolar macrophage dysfunction was secondary to decreased glutathione and subsequent chronic oxidative stress in the alveolar space. After 6 wk of ethanol ingestion, oxidant stress in the alveolar macrophages was evidenced by a 30-mV oxidation of the GSH/GSSG redox potential (P [less than or equal to] 0.05). For control macrophages, ~80% internalized fluorescent Staphylococcus aureus were added in vitro. In contrast, only 20% of the macrophages from the ethanol-fed rats were able to bind and internalize fluorescent S. aureus. This ethanol-induced decreased capacity for phagocytosis was paralleled by increased apoptosis. When added to the ethanol diet, the glutathione precursors procysteine or N-acetyl cysteine normalized glutathione and oxidant stress in the epithelial lining fluid as well as the alveolar macrophages to control values. This attenuation of oxidant stress was associated with normalization of macrophage phagocytosis and viability. These results suggested that decreased glutathione availability in the alcoholic lung contribute to alveolar macrophage dysfunction via oxidative stress, resulting in not only decreased function but decreased viability. oxidative stress; apoptosis; lung; antioxidants

Alcohol abuse markedly increases the risk of sepsis-mediated acute lung injury. In a rat model, ethanol ingestion alone (in the absence of any other stress) causes pulmonary glutathione depletion, increased expression of transforming growth factor-[beta]1 (TGF-[beta]1), and alveolar epithelial barrier dysfunction, even though the lung appears grossly normal. However, during endotoxemia, ethanol-fed rats release more activated TGF-[beta]1 into the alveolar space where it can exacerbate epithelial barrier dysfunction and lung edema. Ethanol ingestion activates the renin-angiotensin system, and angiotensin II is capable of inducing oxidative stress and TGF-[beta]1 expression. We determined that lisinopril, an angiotensin-converting enzyme inhibitor that decreases angiotensin II formation, limited lung glutathione depletion, and treatment with either lisinopril or losartan, a selective angiotensin II type 1 receptor blocker, normalized TGF-[beta]1 expression. The glutathione precursor procysteine also prevented TGF-[beta]1 expression, suggesting that TGF-[beta]1 may be induced indirectly by angiotensin II-mediated oxidative stress and glutathione depletion. Importantly, lisinopril treatment normalized barrier function in alveolar epithelial cell monolayers from ethanol-fed rats, and treatment with either lisinopril or losartan normalized alveolar epithelial barrier function in ethanol-fed rats in vivo, as reflected by lung liquid clearance of an intratracheal saline challenge, even during endotoxemia. In parallel, lisinopril treatment limited TGF-[beta]1 protein release into the alveolar space during endotoxemia. Together, these results suggest that angiotensin II mediates oxidative stress and the consequent TGF-[beta]1 expression and alveolar epithelial barrier dysfunction that characterize the alcoholic lung. acute respiratory distress syndrome; epithelium; angiotensin-converting enzyme; alcohol abuse

Chronic alcohol abuse increases the risk of developing acute lung injury approximately threefold in septic patients, and ethanol ingestion for 6 wk in rats impairs alveolar epithelial barrier function both in vitro and in vivo. Granulocyte/macrophage colony-stimulating factor (GM-CSF) is atrophic factor for the alveolar epithelium, and a recent phase II clinical study suggests that GM-CSF therapy decreases sepsis-mediated lung injury. Therefore, we hypothesized that GM-CSF treatment could improve ethanol-mediated defects in the alveolar epithelium during acute stresses such as endotoxemia. In this study, we determined that recombinant rat GM-CSF improved lung liquid clearance (as reflected by lung tissue wet:dry ratios) in ethanol-fed rats anesthetized and then challenged with 2 ml of saline via a tracheostomy tube. Furthermore, GM-CSF treatment improved lung liquid clearance and decreased epithelial protein leak in both control-fed and ethanol-led rats after 6 h of endotoxemia induced by Salmonella typhimurium lipopolysaccharide given intraperitoneally, but with the greater net effect seen in the ethanol-fed rats. Our previous studies indicate that chronic ethanol ingestion decreases lung liquid clearance by increasing intercellular permeability. Consistent with this, GM-CSF treatment in vitro decreased permeability of alveolar epithelial monolayers derived from both control-fed and ethanol-fed rats. As in the endotoxemia model in vivo, the effect of GM-CSF was most dramatic in the ethanol group. Together, these results indicate that GM-CSF treatment has previously unrecognized effects in promoting alveolar epithelial barrier integrity and that these salutary effects may be particularly relevant in the setting of chronic alcohol abuse. acute respiratory distress syndrome; glutathione; epithelium; surfactant; sepsis

Research was conducted to examine the hypothesis that S-nitrosoglutathione (GSNO) has the ability to enhance neutrophil DNA fragmentation. Incubation of the neutrophiles was conducted in the presence and absence of GSNO and analyzed for cell death using a fluorescent viability/cytotoxicity assay. Results are in good agreement with previous experiment with NO gas exposure and with recent preliminary evidence showing that the NO donor 3-morpholinosynonimine induced a cGMP-independent increase in neutrophil apoptosis.