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Kim YE, Park WS, Sung DK, Ahn SY, Chang YS. Antenatal betamethasone enhanced the detrimental effects of postnatal dexamethasone on hyperoxic lung and brain injuries in newborn rats. PLoS One 2019; 14:e0221847. [PMID: 31469886 PMCID: PMC6716665 DOI: 10.1371/journal.pone.0221847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 08/18/2019] [Indexed: 02/07/2023] Open
Abstract
Purpose To determine the effects of antenatal betamethasone and/or postnatal dexamethasone administration on hyperoxic lung and brain injuries in newborn rats. Methods Newborn Sprague-Dawley rats were divided into five experimental groups: normoxia-vehicle-vehicle group, hyperoxia-vehicle-vehicle group, hyperoxia-betamethasone-vehicle group, hyperoxia-vehicle-dexamethasone group, and hyperoxia-betamethasone-dexamethasone group according to (i) whether rats were exposed to normoxia or hyperoxia after birth to postnatal day (P) 14, (ii) whether antenatal betamethasone (0.2mg/kg) or vehicle was administered to pregnant rats at gestation days 19 and 20, and (iii) whether three tapering doses of dexamethasone (0.5, 0.3, 0.1mg/kg per day) or vehicle were administered on P5, 6 and 7, respectively. The lungs and brains were harvested for histological and biochemical analyses at P8 and P14. Results Postnatal dexamethasone but not antenatal betamethasone significantly enhanced hyperoxia-induced reduction in body weight gain and alveolarization and increased lung terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positive cells both at P8 and P14, transiently increased hyperoxia-induced reductions in brain weight gain and angiogenesis, and increase in brain TUNEL-positive cells at P8 but not at P14. Co-administration of antenatal betamethasone significantly enhanced dexamethasone-induced impairments in alveolarization both at P8 and P14, transient increases in lung and brain oxidative stresses, and increases in brain TUNEL-positive cells at P8 but not at P14. Conclusion Although postnatal dexamethasone but not antenatal betamethasone alone significantly increased hyperoxic lung and brain injuries, co-administration of antenatal betamethasone significantly enhanced the detrimental effects of postnatal dexamethasone on hyperoxic lung and brain injuries in newborn rats.
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Affiliation(s)
- Young Eun Kim
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Stem Cell and Regenerative Medicine Institute, Samsung Medical Center, Seoul, Korea
| | - Won Soon Park
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Stem Cell and Regenerative Medicine Institute, Samsung Medical Center, Seoul, Korea
| | - Dong Kyung Sung
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Stem Cell and Regenerative Medicine Institute, Samsung Medical Center, Seoul, Korea
| | - So Yoon Ahn
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Stem Cell and Regenerative Medicine Institute, Samsung Medical Center, Seoul, Korea
| | - Yun Sil Chang
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Stem Cell and Regenerative Medicine Institute, Samsung Medical Center, Seoul, Korea
- * E-mail:
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Maturu P, Wei-Liang Y, Jiang W, Wang L, Lingappan K, Barrios R, Liang Y, Moorthy B, Couroucli XI. Newborn Mice Lacking the Gene for Cyp1a1 Are More Susceptible to Oxygen-Mediated Lung Injury, and Are Rescued by Postnatal β-Naphthoflavone Administration: Implications for Bronchopulmonary Dysplasia in Premature Infants. Toxicol Sci 2018; 157:260-271. [PMID: 28201809 DOI: 10.1093/toxsci/kfx036] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Prolonged hyperoxia contributes to bronchopulmonary dysplasia (BPD) in preterm infants. β-Naphthoflavone (BNF) is a potent inducer of cytochrome P450 (CYP)1A enzymes, which have been implicated in hyperoxic injuries in adult mice. In this investigation, we tested the hypothesis that newborn mice lacking the Cyp1a1 gene would be more susceptible to hyperoxic lung injury than wild-type (WT) mice and that postnatal BNF treatment would rescue this phenotype by mechanisms involving CYP1A and/or NAD(P)H quinone oxidoreductase (NQO1) enzymes. Newborn WT or Cyp1a1-null mice were treated with BNF (10 mg/kg) or the vehicle corn oil (CO) i.p., from postnatal day (PND) 2 to 14 once every other day, while being maintained in room air or hyperoxia (85% O2) for 14 days. Both genotypes showed lung injury, inflammation, and alveolar simplification in hyperoxia, with Cyp1a1-null mice displaying increased susceptibility compared to WT mice. BNF treatment resulted in significant attenuation of lung injury and inflammation, with improved alveolarization in both WT and Cyp1a1-null mice. BNF exposed normoxic or hyperoxic WT mice showed increased expression of hepatic CYP1A1/1A2, pulmonary CYP1A1, and NQO1 expression at both mRNA and protein levels, compared with vehicle controls. However, BNF caused greater induction of hepatic CYP1A2 and pulmonary NQO1 enzymes in the Cyp1a1-null mice, suggesting that BNF protects against hyperoxic lung injury in WT and Cyp1a1-null mice through the induction of CYP1A and NQO1 enzymes. Further studies on the protective role of flavonoids against hyperoxic lung injury in newborns could lead to novel strategies for the prevention and/or treatment of BPD.
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Affiliation(s)
- Paramahamsa Maturu
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Yanhong Wei-Liang
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Weiwu Jiang
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Lihua Wang
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Krithika Lingappan
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Roberto Barrios
- Department of Pathology and Genomic Medicine, The Methodist Hospital Physician Organization, Houston, Texas, USA
| | - Yao Liang
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Bhagavatula Moorthy
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
| | - Xanthi I Couroucli
- Section of Neonatology, Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas, USA
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Maturu P, Wei-Liang Y, Androutsopoulos VP, Jiang W, Wang L, Tsatsakis AM, Couroucli XI. Quercetin attenuates the hyperoxic lung injury in neonatal mice: Implications for Bronchopulmonary dysplasia (BPD). Food Chem Toxicol 2018; 114:23-33. [PMID: 29432836 DOI: 10.1016/j.fct.2018.02.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 12/19/2022]
Abstract
Quercetin (QU) is one of the most common flavonoids that are present in a wide variety of fruits, vegetables, and beverages. This compound possesses potent anti-inflammatory and anti-oxidant properties. Supplemental oxygen is routinely administered to premature infants with pulmonary insufficiency. However, hyperoxia is one of the major risk factors for the development of bronchopulmonary dysplasia (BPD), which is also termed chronic lung disease in premature infants. Currently, no preventive approaches have been reported against BPD. The treatment of BPD is notably limited to oxygen administration, ventilatory support, and steroids. Since QU has been shown to be effective in reducing inflammation and oxidative stress in various disease models, we hypothesized that the postnatal QU treatment of newborn mice will protect against hyperoxic lung injury by the upregulation of the phase I (CYP1A/B) and/or phase II, NADPH quinone reductase enzymes. Newborn C57BL/6J mice within 24 h of birth with the nursing dams were exposed to either 21% O2 (air) and/or 85% O2 (hyperoxia) for 7 days. The mice were treated, intraperitoneally (i.p.) once every other day with quercetin, at a concentration of 20 mg/kg, or saline alone from postnatal day (PND) 2-6. The mice were sacrificed on day 7, and lung and liver tissues were collected. The expression levels of CYP1A1, CYP1B1, NQO1 proteins and mRNA as well as the levels of MDA-protein adducts were analyzed in lung and liver tissues. The findings indicated that QU attenuated hyperoxia-mediated lung injury by reducing inflammation and improving alveolarization with decreased number of neutrophil and macrophage infiltration. The attenuation of this lung injury correlated with the upregulation of CYP1A1/CYP1B1/NQO1 mRNA, proteins and the down regulation of NF-kB levels and MDA-protein adducts in lung and liver tissues. The present study demonstrated the potential therapeutic value of quercetin in the prevention and/or treatment of BPD.
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Affiliation(s)
- Paramahamsa Maturu
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Yanhong Wei-Liang
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Vasilis P Androutsopoulos
- Laboratory of Toxicology, University of Crete, Medical School, Voutes, Heraklion 71409, Crete, Greece
| | - Weiwu Jiang
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Lihua Wang
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Aristides M Tsatsakis
- Laboratory of Toxicology, University of Crete, Medical School, Voutes, Heraklion 71409, Crete, Greece
| | - Xanthi I Couroucli
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.
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dos Reis FF, Reboredo MDM, Lucinda LMF, Bianchi AMA, Rabelo MAE, da Fonseca LMC, de Oliveira JCA, Pinheiro BV. Pre-treatment with dexamethasone attenuates experimental ventilator-induced lung injury. J Bras Pneumol 2016; 42:166-73. [PMID: 27383928 PMCID: PMC5569612 DOI: 10.1590/s1806-37562015000000350] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 05/09/2016] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To evaluate the effects that administering dexamethasone before the induction of ventilator-induced lung injury (VILI) has on the temporal evolution of that injury. METHODS Wistar rats were allocated to one of three groups: pre-VILI administration of dexamethasone (dexamethasone group); pre-VILI administration of saline (control group); or ventilation only (sham group). The VILI was induced by ventilation at a high tidal volume. Animals in the dexamethasone and control groups were euthanized at 0, 4, 24, and 168 h after VILI induction. We analyzed arterial blood gases, lung edema, cell counts (total and differential) in the BAL fluid, and lung histology. RESULTS At 0, 4, and 24 h after VILI induction, acute lung injury (ALI) scores were higher in the control group than in the sham group (p < 0.05). Administration of dexamethasone prior to VILI induction decreased the severity of the lung injury. At 4 h and 24 h after induction, the ALI score in the dexamethasone group was not significantly different from that observed for the sham group and was lower than that observed for the control group (p < 0.05). Neutrophil counts in BAL fluid were increased in the control and dexamethasone groups, peaking at 4 h after VILI induction (p < 0.05). However, the neutrophil counts were lower in the dexamethasone group than in the control group at 4 h and 24 h after induction (p < 0.05). Pre-treatment with dexamethasone also prevented the post-induction oxygenation impairment seen in the control group. CONCLUSIONS Administration of dexamethasone prior to VILI induction attenuates the effects of the injury in Wistar rats. The molecular mechanisms of such injury and the possible clinical role of corticosteroids in VILI have yet to be elucidated. OBJETIVO Avaliar os efeitos da administração de dexametasona antes da indução de lesão pulmonar induzida por ventilação mecânica (LPIVM) na evolução temporal dessa lesão. MÉTODOS Ratos Wistar foram alocados em um dos três grupos: administração de dexametasona pré-LPIVM (grupo dexametasona); administração de salina pré-LPIVM (grupo controle); e somente ventilação (grupo sham). A LPIVM foi realizada por ventilação com volume corrente alto. Os animais dos grupos dexametasona e controle foram sacrificados em 0, 4, 24 e 168 h após LPIVM. Analisamos gasometria arterial, edema pulmonar, contagens de células (totais e diferenciais) no lavado broncoalveolar e histologia de tecido pulmonar. RESULTADOS Em 0, 4 e 24 h após LPIVM, os escores de lesão pulmonar aguda (LPA) foram maiores no grupo controle que no grupo sham (p < 0,05). A administração de dexametasona antes da LPIVM reduziu a gravidade da lesão pulmonar. Em 4 e 24 h após a indução, o escore de LPA no grupo dexametasona não foi significativamente diferente daquele observado no grupo sham e foi menor que o observado no grupo controle (p < 0,05). As contagens de neutrófilos no lavado broncoalveolar estavam aumentadas nos grupos controle e dexametasona, com pico em 4 h após LPIVM (p < 0,05). Entretanto, as contagens de neutrófilos foram menores no grupo dexametasona que no grupo controle em 4 e 24 h após LPIVM (p < 0,05). O pré-tratamento com dexametasona também impediu o comprometimento da oxigenação após a indução visto no grupo controle. CONCLUSÕES A administração de dexametasona antes de LPIVM atenua os efeitos da lesão em ratos Wistar. Os mecanismos moleculares dessa lesão e o possível papel clínico dos corticosteroides na LPIVM ainda precisam ser elucidados.
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Affiliation(s)
- Fernando Fonseca dos Reis
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
| | - Maycon de Moura Reboredo
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
| | - Leda Marília Fonseca Lucinda
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
| | - Aydra Mendes Almeida Bianchi
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
| | | | - Lídia Maria Carneiro da Fonseca
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
| | | | - Bruno Valle Pinheiro
- . Laboratório de Pesquisa em Pneumologia, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
- . Centro de Biologia da Reprodução, Universidade Federal de Juiz de Fora, Juiz de Fora (MG) Brasil
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Engel M, Nowacki RME, Boden P, Reiss LK, Uhlig S, Reynaert NL, Gopal P, Wouters EFM, Willems CHMP, Kloosterboer N, Wolfs TGAM, Zimmermann LJI, Vos GD, Kramer BW. The Effects of Dexamethasone and Oxygen in Ventilated Adult Sheep with Early Phase Acute Respiratory Distress Syndrome. Lung 2014; 193:97-103. [DOI: 10.1007/s00408-014-9670-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 12/01/2014] [Indexed: 02/06/2023]
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Dexamethasone attenuates VEGF expression and inflammation but not barrier dysfunction in a murine model of ventilator-induced lung injury. PLoS One 2013; 8:e57374. [PMID: 23451215 PMCID: PMC3581459 DOI: 10.1371/journal.pone.0057374] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 01/21/2013] [Indexed: 12/15/2022] Open
Abstract
Background Ventilator–induced lung injury (VILI) is characterized by vascular leakage and inflammatory responses eventually leading to pulmonary dysfunction. Vascular endothelial growth factor (VEGF) has been proposed to be involved in the pathogenesis of VILI. This study examines the inhibitory effect of dexamethasone on VEGF expression, inflammation and alveolar–capillary barrier dysfunction in an established murine model of VILI. Methods Healthy male C57Bl/6 mice were anesthetized, tracheotomized and mechanically ventilated for 5 hours with an inspiratory pressure of 10 cmH2O (“lower” tidal volumes of ∼7.5 ml/kg; LVT) or 18 cmH2O (“higher” tidal volumes of ∼15 ml/kg; HVT). Dexamethasone was intravenously administered at the initiation of HVT–ventilation. Non–ventilated mice served as controls. Study endpoints included VEGF and inflammatory mediator expression in lung tissue, neutrophil and protein levels in bronchoalveolar lavage fluid, PaO2 to FiO2 ratios and lung wet to dry ratios. Results Particularly HVT–ventilation led to alveolar–capillary barrier dysfunction as reflected by reduced PaO2 to FiO2 ratios, elevated alveolar protein levels and increased lung wet to dry ratios. Moreover, VILI was associated with enhanced VEGF production, inflammatory mediator expression and neutrophil infiltration. Dexamethasone treatment inhibited VEGF and pro–inflammatory response in lungs of HVT–ventilated mice, without improving alveolar–capillary permeability, gas exchange and pulmonary edema formation. Conclusions Dexamethasone treatment completely abolishes ventilator–induced VEGF expression and inflammation. However, dexamethasone does not protect against alveolar–capillary barrier dysfunction in an established murine model of VILI.
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Yubero S, Manso MA, Ramudo L, Vicente S, De Dios I. Dexamethasone down-regulates the inflammatory mediators but fails to reduce the tissue injury in the lung of acute pancreatitis rat models. Pulm Pharmacol Ther 2012; 25:319-24. [PMID: 22691809 DOI: 10.1016/j.pupt.2012.05.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 05/30/2012] [Accepted: 05/31/2012] [Indexed: 01/22/2023]
Abstract
Pulmonary complications are frequent in the course of acute pancreatitis. We investigate the effects of dexamethasone on lung injury in mild and severe AP. Mild and severe acute pancreatitis was induced in rats by bile-pancreatic duct obstruction and infusion of 3.5% sodium taurocholate into the bile-pancreatic duct, respectively. Dexamethasone (1 mg/kg) was given by intramuscular injection 1 h after acute pancreatitis. Plasma amylase activity was measured to evaluate the pancreas damage. Lungs were harvested for analysing mRNA expression of monocyte chemoattractant protein-1 (MCP-1), cytokine-induced neutrophil chemoattractant (CINC), P-selectin and intercellular adhesion molecule-1 (ICAM-1), myeloperoxidase (MPO) activity (as index of neutrophil infiltration) and histological examination. Dexamethasone reduced the hyperamylasemia and hindered the pulmonary upregulation of MCP-1, CINC, P-selectin and ICAM-1, in both mild and severe acute pancreatitis. Despite this, dexamethasone treatment failed to reduce MPO activity and histological alterations developed in lungs during acute pancreatitis, either in bile-pancreatic duct obstruction or sodium taurocholate model. We conclude that pulmonary local factors different from inflammatory mediators contribute to leukocyte recruitment, so that although dexamethasone down-regulated the lung expression of chemokines and adhesion molecules during acute pancreatitis it was not able to prevent leukocyte infiltration, which could be responsible for maintaining the lung injury in either mild or severe acute pancreatitis.
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Affiliation(s)
- Sara Yubero
- Department of Physiology and Pharmacology, IBSAL (Instituto Biosanitario Salamanca), University of Salamanca, 37007 Salamanca, Spain
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Couroucli XI, Liang YHW, Jiang W, Wang L, Barrios R, Yang P, Moorthy B. Prenatal administration of the cytochrome P4501A inducer, Β-naphthoflavone (BNF), attenuates hyperoxic lung injury in newborn mice: implications for bronchopulmonary dysplasia (BPD) in premature infants. Toxicol Appl Pharmacol 2011; 256:83-94. [PMID: 21745492 DOI: 10.1016/j.taap.2011.06.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 06/07/2011] [Accepted: 06/08/2011] [Indexed: 12/16/2022]
Abstract
Supplemental oxygen contributes to the development of bronchopulmonary dysplasia (BPD) in premature infants. In this investigation, we tested the hypothesis that prenatal treatment of pregnant mice (C57BL/6J) with the cytochrome P450 (CYP)1A1 inducer, ß-napthoflavone (BNF), will lead to attenuation of lung injury in newborns (delivered from these dams) exposed to hyperoxia by mechanisms entailing transplacental induction of hepatic and pulmonary CYP1A enzymes. Pregnant mice were administered the vehicle corn oil (CO) or BNF (40 mg/kg), i.p., once daily for 3 days on gestational days (17-19), and newborns delivered from the mothers were either maintained in room air or exposed to hyperoxia (>95% O(2)) for 1-5 days. After 3-5 days of hyperoxia, the lungs of CO-treated mice showed neutrophil infiltration, pulmonary edema, and perivascular inflammation. On the other hand, BNF-pretreated neonatal mice showed decreased susceptibility to hyperoxic lung injury. These mice displayed marked induction of ethoxyresorufin O-deethylase (EROD) (CYP1A1) and methoxyresorufin O-demethylase (MROD) (CYP1A2) activities, and levels of the corresponding apoproteins and mRNA levels until PND 3 in liver, while CYP1A1 expression alone was augmented in the lung. Prenatal BNF did not significantly alter gene expression of pulmonary NAD(P)H quinone reductase (NQO1). Hyperoxia for 24-72 h resulted in increased pulmonary levels of the F(2)-isoprostane 8-iso-PGF(2α), whose levels were decreased in mice prenatally exposed to BNF. In conclusion, our results suggest that prenatal BNF protects newborns against hyperoxic lung injury, presumably by detoxification of lipid hydroperoxides by CYP1A enzymes, a phenomenon that has implications for prevention of BPD in infants.
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Affiliation(s)
- Xanthi I Couroucli
- Section of Neonatology, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
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Effects of dexamethasone on intercellular adhesion molecule 1 expression and inflammatory response in necrotizing acute pancreatitis in rats. Pancreas 2010; 39:1057-63. [PMID: 20442680 DOI: 10.1097/mpa.0b013e3181da0f3e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Adhesion molecules are involved in the inflammatory response during acute pancreatitis (AP). We investigated the effect of dexamethasone (Dx) on intercellular adhesion molecule 1 (ICAM-1) expression during AP and its consequences on leukocyte recruitment and pancreatic damage. METHODS Acute pancreatitis was induced in rats by 3.5% sodium taurocholate for 3 hours and 6 hours. Dexamethasone (1 mg/kg) was administered either 30 minutes before or 1 hour after inducing AP. Messenger RNA ICAM-1 expression in pancreas and lung, membrane-bound ICAM-1 in acinar cells, and ICAM-1 plasma levels were analyzed. Histological examination of the pancreas and neutrophil infiltration in pancreas and lung were also measured. RESULTS Prophylactic and therapeutic administration of Dx down-regulated ICAM-1 expression in pancreas and lung from early AP. Dexamethasone given before AP reduced the pancreatic damage, but lung inflammation was not prevented. Therapeutic Dx treatment was ineffective in avoiding leukocyte recruitment into the pancreas and lung in rats with AP. High ICAM-1 concentration was found in plasma during AP, which was not reduced by Dx treatments. CONCLUSIONS Dexamethasone down-regulates ICAM-1 expression, but it does not completely prevent leukocyte recruitment during sodium taurocholate-induced AP.
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Abstract
Premature infants often develop serious clinical complications associated with respiratory failure and hyperoxic lung injury that includes lung inflammation and alterations in lung development. The goal of these studies is to test the hypothesis that there are differences in the course of lung injury in newborn mice exposed to 85% or >95% oxygen that provide models to address the differential effects of oxidation and inflammation. Our results indicate differences between the 85% and >95% O2 exposure groups by day 14 in weight gain and lung alveolarization. Inflammation, assessed by neutrophil counts, was observed in both hyperoxia groups by day 3 but was dramatically greater in the >95% O2-exposed groups by day 14 and associated with greater developmental deficits. Cytoplasmic phospholipase A2, cyclooxygenase-2, and 5-lipoxygenase levels were elevated but no patterns of differences were observed between exposure groups. Prostaglandins D2, E2, and F2alpha were increased in the tissues from mouse pups exposed to >95% O2 at 7 d indicating a differential expression of cyclooxygenase-2 products. Our data indicate that there are differences in the models of 85% or >95% O2 exposure and these differences may provide mechanistic insights into hyperoxic lung injury in an immature system.
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Affiliation(s)
- Lynette K Rogers
- The Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Department of Pediatrics, Ohio State University, Columbus, Ohio 43205, USA.
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Abstract
BACKGROUND Local anesthetics inhibit mediator and free radical release from polymorphonuclear granulocytes and migration to their site of action. In a recent study, lidocaine significantly improved the alveolar-arterial oxygen difference gradients (A-aDO2) after tracheal instillation of acid in rabbits. The purpose of the current study was to evaluate the effects of lidocaine and pulse-dose steroids on human breast milk (HBM)-induced lung injury in rabbits. METHODS After Animal Care Committee approval, six adult rabbits were assigned to each of three treatments: control, lidocaine, and steroids. After induction of anesthesia and controlled ventilation, acidified HBM at pH 1.8 and volume 1.2 ml.kg(-1) was instilled into the trachea. Rabbits in the lidocaine group received lidocaine 2 mg.kg(-1) i.v. before tracheal instillation and then 2 mg.kg(-1).h(-1) i.v. continuously. Rabbits in the steroid group received 30 mg.kg(-1) methylprednisolone before tracheal instillation. A-aDO2, static compliance and blood for white cell count, and cytokine interleukin-8 (IL-8) concentration were obtained at baseline and at 1 and 4 h postinstillation. After 4 h, the rabbits were killed. The left upper lobe was isolated and excised to determine the wet/dry ratio. The right lung was lavaged with 30 ml normal saline to determine the white cell count and the concentrations of albumin and IL-8. Data were analyzed using one- or two-way anova with repeated measures and an Student-Newman-Keuls (SNK) posthoc test (P < 0.05). RESULTS All rabbits completed the protocol. A-aDO2 and CO2 tensions increased significantly at 1 and 4 h compared with baseline, although there were no differences among the treatments (P < 0.05). Compliance in the control group decreased compared with lidocaine and steroids. CONCLUSION We conclude that preemptive lidocaine and steroids attenuate in part HBM-induced lung injury in rabbits.
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Affiliation(s)
- Thomas Howlett
- The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
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Dallas DV, Keeney SE, Mathews MJ, Schmalstieg FC. Effects of postnatal dexamethasone on oxygen toxicity in neonatal rats. Neonatology 2004; 86:145-54. [PMID: 15205572 DOI: 10.1159/000079114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2003] [Accepted: 04/06/2004] [Indexed: 11/19/2022]
Abstract
We investigated the effect of timing of early postnatal dexamethasone on survival of hyperoxia-exposed neonatal rats. Pups <24 h old were treated with a tapering course of dexamethasone or saline beginning either prior to exposure (day 0), or after 2, 4, or 6 days of > or =98% O2 (n=11-14) or air (n=8-11). Exposures were continued for 14 days. By day 14, day 0 pups had poor survival regardless of the exposure (14% in O2, 13% in air). Survival of pups treated with dexamethasone after 2, 4 and 6 days of O2 exposure was significantly higher at 14 days (50, 86 and 79%, respectively) compared to saline O2 controls (9%, p < 0.001 for each). Pulmonary biochemical analyses were conducted after exposure for 7 days in rat pups treated with dexamethasone or saline beginning after 4 days of exposure to air or O2 (n=11-12 for each group). While pups treated with dexamethasone showed greatly improved survival compared to O2 controls, there was no decrease in neutrophil influx into the lung as measured by lung myeloperoxidase and neutrophil counts in histologic specimens and lavage fluid. Catalase, glutathione peroxidase, total and manganese superoxide dismutase activities as well as manganese superoxide dismutase (MnSOD) mRNA expression were elevated in both O2 groups after 7 days compared to the air groups (p < 0.05) and MnSOD mRNA expression was elevated in the O2/dexamethasone group, but there were no differences between dexamethasone and saline groups in O2. Thus, this study indicates that the timing of dexamethasone administration is crucial. Mechanisms other than increases in antioxidant enzymes or decreases in lung neutrophils underlie the ability of dexamethasone to improve survival of these neonatal rats.
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Affiliation(s)
- Dara Varga Dallas
- Department of Pediatrics, The University of Texas Medical Branch, Galveston, TX 77555-0526, USA.
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Jiang W, Welty SE, Couroucli XI, Barrios R, Kondraganti SR, Muthiah K, Yu L, Avery SE, Moorthy B. Disruption of the Ah receptor gene alters the susceptibility of mice to oxygen-mediated regulation of pulmonary and hepatic cytochromes P4501A expression and exacerbates hyperoxic lung injury. J Pharmacol Exp Ther 2004; 310:512-9. [PMID: 15123765 DOI: 10.1124/jpet.103.059766] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Administration of supplemental oxygen is frequently encountered in infants suffering from pulmonary insufficiency and in adults with acute respiratory distress syndrome. However, hyperoxia causes acute lung damage in experimental animals. In the present study, we investigated the roles of the Ah receptor (AHR) in the modulation of cytochrome P4501A (CYP1A) enzymes and in the development of lung injury by hyperoxia. Adult male wild-type [AHR (+/+)] mice and AHR-deficient animals [AHR (-/-)] were maintained in room air or exposed to hyperoxia (>95% oxygen) for 24 to 72 h, and pulmonary and hepatic expression of CYP1A and lung injury were studied. Hyperoxia caused significant increases in pulmonary and hepatic CYP1A1 activities (ethoxyresorufin O-deethylase) and mRNA levels in wild-type (C57BL/6J) AHR (+/+), but not AHR (-/-) mice, suggesting that AHR-dependent mechanisms contributed to CYP1A1 induction. On the other hand, hyperoxia augmented hepatic CYP1A2 expression in both wild-type and AHR (-/-) animals, suggesting that AHR-independent mechanisms contributed to the CYP1A2 regulation by hyperoxia. AHR (-/-) mice exposed to hyperoxia were more susceptible than wild-type mice to lung injury and inflammation, as indicated by significantly higher lung weight/body weight ratios, increased pulmonary edema, and enhanced neutrophil recruitment into the lungs. In conclusion, our results support the hypothesis that the hyperoxia induces CYP1A1, but not CYP1A2, expression in vivo by AHR-dependent mechanisms, a phenomenon that may mechanistically contribute to the beneficial effects of the AHR in hyperoxic lung injury.
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Affiliation(s)
- Weiwu Jiang
- Department of Pediatrics, Baylor College of Medicine, 6621 Fannin, FC 530.01, Houston, TX 77030, USA. .
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Febrile-range hyperthermia augments pulmonary neutrophil recruitment and amplifies pulmonary oxygen toxicity. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 162:2005-17. [PMID: 12759256 PMCID: PMC1868125 DOI: 10.1016/s0002-9440(10)64333-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Febrile-range hyperthermia (FRH) improves survival in experimental infections by accelerating pathogen clearance, but may also increase collateral tissue injury. We hypothesized that FRH would worsen the outcome of inflammation stimulated by a non-replicating agonist and tested this hypothesis in a murine model of pulmonary oxygen toxicity. Using a conscious, temperature-controlled mouse model, we showed that maintaining a core temperature at FRH (39 degrees C to 40 degrees C) rather than at euthermic levels (36.5 degrees C to 37 degrees C) during hyperoxia exposure accelerated lethal pulmonary vascular endothelial injury, reduced the inspired oxygen threshold for lethality, induced expression of granulocyte-colony stimulating factor, and expanded the circulating neutrophil pool. In these same mice, FRH augmented pulmonary expression of the ELR(+) CXC chemokines, KC and LPS-induced CXC chemokine, enhanced recruitment of neutrophils, and changed the histological pattern of lung injury to a neutrophilic interstitial pneumonitis. Immunoblockade of CXC receptor-2 abrogated neutrophil recruitment, reduced pulmonary vascular injury, and delayed death. These combined data demonstrate that FRH may enlist distinct mediators and effector cells to profoundly shift the host response to a defined injurious stimulus, in part by augmenting delivery of neutrophils to sites of inflammation, such as may occur in infections. In certain conditions, such as in the hyperoxic lung, this process may be deleterious.
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15
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Couroucli XI, Welty SE, Geske RS, Moorthy B. Regulation of pulmonary and hepatic cytochrome P4501A expression in the rat by hyperoxia: implications for hyperoxic lung injury. Mol Pharmacol 2002; 61:507-15. [PMID: 11854430 DOI: 10.1124/mol.61.3.507] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Supplemental oxygen therapy is frequently used in the treatment of pulmonary insufficiency, as is encountered in premature infants, and in patients with acute respiratory distress syndrome. However, hyperoxia causes lung damage in experimental animals and may do so in humans. Cytochrome P4501A enzymes have been implicated in hyperoxic lung injury. In this study, we investigated the mechanisms of CYP1A1 regulation by hyperoxia and tested the hypothesis that aryl hydrocarbon receptor (AHR)-dependent mechanisms contribute to induction of CYP1A1 and that modulation of CYP1A by hyperoxia may have implications for lung injury. Exposure of adult male Sprague-Dawley rats to hyperoxia for 24 to 48 h led to increased expression of pulmonary CYP1A1 enzyme, which was preceded by enhancement of the corresponding mRNA, followed by decline of induction at 60 h, when the animals displayed severe respiratory distress and lung inflammation. Similarly, hepatic CYP1A1/1A2 mRNAs were markedly induced between 24 and 48 h of hyperoxia, with induction declining by 60 h. Electrophoretic mobility shift assays (EMSA) and experiments with AHR (-/-) mice indicated that AHR-dependent mechanisms contributed to CYP1A induction. The AHR (-/-) mice were refractory to CYP1A1 induction by hyperoxia and were more sensitive to lung injury than wild-type mice. Lungs of hyperoxic rats showed increase in the expression of CYP1A1 in airway epithelial cells, type II pneumocytes, and endothelial cells. In conclusion, our results suggest that induction of CYP1A1 by hyperoxia is mediated by AHR-dependent mechanisms and that modulation of CYP1A enzymes by hyperoxia may have implications for hyperoxic lung injury.
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Affiliation(s)
- Xanthi I Couroucli
- Department of Pediatrics, University of Texas-Houston Medical School, Houston, Texas, USA
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16
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Ramsay PL, DeMayo FJ, Hegemier SE, Wearden ME, Smith CV, Welty SE. Clara cell secretory protein oxidation and expression in premature infants who develop bronchopulmonary dysplasia. Am J Respir Crit Care Med 2001; 164:155-61. [PMID: 11435254 DOI: 10.1164/ajrccm.164.1.2008022] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD) is a chronic lung disease that affects prematurely born infants and appears to evolve in part from early inflammatory responses in the lung. The inflammatory responses have been associated with protein and lipid oxidation in tracheal aspirate fluids. The present study was designed to test the hypothesis that in the first week of life specific oxidations and/ or altered expressions of proteins would be observed in tracheal aspirate fluids in infants who would subsequently develop BPD. We obtained tracheal aspirate fluids on Days of life 1, 3, and 6 from infants born at < or = 29 wk gestation, incubated the fluids with 2,4-dinitrophenylhyrazine (DNPH), separated the proteins electrophoretically, and assessed DNPH reactivity by immunonblots. DNPH reactivity of a protein that was identified as Clara cell secretory protein (CCSP) was observed more consistently in tracheal aspirate fluids from infants who later developed BPD than from infants who did not develop BPD. Tracheal aspirate fluid levels of immunoreactive CCSP were also lower on Day of life 1 in infants who developed BPD than in those who did not develop BPD. Increased CCSP oxidation and decreased immunoreactive CCSP expression in infants who subsequently developed BPD suggest that Clara cell function and CCSP expression may be critical for normal bronchoalveolar fluid homeostasis and that maintaining CCSP expression and function may be useful goals for targeted therapies for inhibition of the development of BPD.
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Affiliation(s)
- P L Ramsay
- Department of Pediatrics, Baylor College of Medicine, Houston Texas, USA
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17
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Williams EA, Welty SE, Geske RS, Hubble CL, Craig DM, Quick G, Meliones JN, Cheifetz IM. Liquid lung ventilation reduces neutrophil sequestration in a neonatal swine model of cardiopulmonary bypass. Crit Care Med 2001; 29:789-95. [PMID: 11373470 DOI: 10.1097/00003246-200104000-00021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Liquid lung ventilation has been demonstrated to improve cardiorespiratory function after cardiopulmonary bypass. We hypothesized that liquid lung ventilation (LLV) would decrease the pulmonary inflammatory response after cardiopulmonary bypass (CPB). DESIGN Prospective, randomized, experimental, controlled, nonblinded study. SETTING Animal research laboratory at a university setting. SUBJECTS A total of 24 neonatal piglets. INTERVENTIONS After intubation with a cuffed endotracheal tube, swine were conventionally ventilated. After surgical cannulation, each piglet was placed on conventional nonpulsatile CPB and cooled to 18 degrees C (64.4 degrees F). Subsequently, the animals were exposed to 90 mins of low-flow CPB (35 mL/kg/min). Animals were rewarmed to 37 degrees C (98.6 degrees F), removed from CPB, and ventilated for 90 min. Ten animals received conventional gas ventilation only (control), seven received initiation of LLV before CPB (prevention), and seven received initiation of LLV during the rewarming phase of CPB (treatment). After the animals were killed, the lungs were removed en bloc. The left lobe was dissected and formalin-fixed at 20 cm H2O overnight, followed by paraffin embedding. Sections were taken from the paraffin-embedded lungs. Neutrophil accumulation and lung injury were assessed by histochemical staining with leukocyte esterase and morphometrics, respectively. One hundred microscopic images were digitized from each tissue sample for lung morphometrics, and neutrophil counts were obtained from every fifth image. MEASUREMENTS AND MAIN RESULTS Lung tissue sections showed a significantly lower number of neutrophils per alveolar area in the prevention and treatment groups than in the control group (control 681 +/- 65, prevention 380 +/- 49, treatment 412 +/- 101 neutrophils per alveolar area [cells/mm2]; p <.05 for both prevention and treatment compared with control). There were no differences in lung injury as assessed with morphometrics or hemodynamic measurements between any of the three groups. CONCLUSIONS The data suggest that LLV reduces the CPB-induced neutrophil sequestration in the pulmonary parenchyma independent of its effects on the circulatory physiology or evidence of early lung injury.
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Affiliation(s)
- E A Williams
- Department of Pediatrics, Duke University Medical Center, Durham, NC 27710, USA
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Abstract
Lung injury after aspiration, although very rare, is a feared and potentially devastating sequela after anaesthesia. This paper summarizes the most recent studies in aspiration lung injury focusing on its clinical epidemiology, new insights in its pathophysiology and innovative concepts in its prevention and therapy.
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Affiliation(s)
- G C Petroz
- Department of Anaesthesia, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
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