1
|
Ju Y, Sun X, Xu G, Tai Q, Gao W. Annexin A1 peptide Ac2-26 mitigates ventilator-induced lung injury in acute respiratory distress syndrome rats and partly depended on the endothelial nitric oxide synthase pathway. Acta Cir Bras 2023; 37:e371203. [PMID: 36651428 PMCID: PMC9974014 DOI: 10.1590/acb371203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 11/22/2022] [Indexed: 01/15/2023] Open
Abstract
PURPOSE Although mechanical ventilation is an essential support for acute respiratory distress syndrome (ARDS), ventilation also leads to ventilator-induced lung injury (VILI). This study aimed to estimate the effect and mechanism of Annexin A1 peptide (Ac2-26) on VILI in ARDS rats. METHODS Thirty-two rats were randomized into the sham (S), mechanical ventilation (V), mechanical ventilation/Ac2-26 (VA), and mechanical ventilation/Ac2-26/L-NIO (VAL) groups. The S group only received anesthesia, and the other three groups received endotoxin and then ventilation for 4 h. Rats in the V, VA and VAL groups received saline, Ac2-26, and A c2-26/N5-(1-iminoethyl)-l-ornithine (L-NIO), respectively. RESULTS All indexes deteriorated in the V, VA and VAL groups compared with the S group. Compared with V group, the PaO2/FiO2 ratio was increased, but the wet-to-dry weight ratio and protein levels in bronchoalveolar lavage fluid were decreased in the VA group. The inflammatory cells and proinflammatory factors were reduced by Ac2-26. The oxidative stress response, lung injury and apoptosis were also decreased by Ac2-26 compared to V group. All improvements of Ac2-26 were partly reversed by L-NIO. CONCLUSIONS Ac2-26 mitigates VILI in ARDS rats and partly depended on the endothelial nitric oxide synthase pathway.
Collapse
Affiliation(s)
- Yingnan Ju
- MD. Harbin Medical University – Department of Intensive Care Unit – Third Clinical College – Harbin, China
| | - Xikun Sun
- MS. Harbin Medical University – Department of Anesthesiology – The Second Affiliated Hospital – Harbin, China
| | - Guangxiao Xu
- MS. Harbin Medical University – Department of Anesthesiology – The Second Affiliated Hospital – Harbin, China
| | - Qihang Tai
- MS. Harbin Medical University – Department of Anesthesiology – The Second Affiliated Hospital – Harbin, China
| | - Wei Gao
- MS. Harbin Medical University – Department of Anesthesiology – The Second Affiliated Hospital – Harbin, China.,Corresponding author:
- (86-0451) 86605029
| |
Collapse
|
2
|
Mechanical Ventilation with Moderate Tidal Volume Exacerbates Extrapulmonary Sepsis-Induced Lung Injury via IL33-WISP1 Signaling Pathway. Shock 2020; 56:461-472. [PMID: 33394970 DOI: 10.1097/shk.0000000000001714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
ABSTRACT IL-33 and WNT1-inducible secreted protein (WISP1) play central roles in acute lung injury (ALI) induced by mechanical ventilation with moderate tidal volume (MTV) in the setting of sepsis. Here, we sought to determine the inter-relationship between IL-33 and WISP1 and the associated signaling pathways in this process.We used a two-hit model of cecal ligation puncture (CLP) followed by MTV ventilation (4 h 10 mL/kg) in wild-type, IL-33-/- or ST2-/- mice or wild-type mice treated with intratracheal antibodies to WISP1. Macrophages (Raw 264.7 and alveolar macrophages from wild-type or ST2-/- mice) were used to identify specific signaling components.CLP + MTV resulted in ALI that was partially sensitive to genetic ablation of IL-33 or ST2 or antibody neutralization of WISP1. Genetic ablation of IL-33 or ST2 significantly prevented ALI after CLP + MTV and reduced levels of WISP1 in the circulation and bronchoalveolar lung fluid. rIL-33 increased WISP1 in alveolar macrophages in an ST2, PI3K/AKT, and ERK dependent manner. This WISP1 upregulation and WNT β-catenin activation were sensitive to inhibition of the β-catenin/TCF/CBP/P300 nuclear pathway.We show that IL-33 drives WISP1 upregulation and ALI during MTV in CLP sepsis. The identification of this relationship and the associated signaling pathways reveals a number of possible therapeutic targets to prevent ALI in ventilated sepsis patients.
Collapse
|
3
|
Wang X, Gong J, Zhu J, Jin Z, Gao W. Alpha 1-antitrypsin for treating ventilator-associated lung injury in acute respiratory distress syndrome rats. Exp Lung Res 2019; 45:209-219. [PMID: 31347410 DOI: 10.1080/01902148.2019.1642968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose: Mechanical ventilation (MV) is an essential life support tool for patients with acute respiratory distress syndrome (ARDS). However, MV for ARDS can result in ventilator-induced lung injury (VILI). This study aimed to assess whether alpha 1-antitrypsin (AAT) can reduce VILI in ARDS rats. Materials and Methods: Rats were randomly divided into five groups: the sham (S) group, MV (V) group, lipopolysaccharide (LPS) (L) group, MV/LPS (VL) group and MV/AAT (VA) group. Rats in the S group were anesthetized. The rats in the L group received LPS but not ventilation, the rats in the V group received only MV, and the rats in the VL and VA groups received LPS and MV. Additionally, the rats in the VA group were treated with AAT, and the other rats were injected with saline. The PaO2/FiO2 ratio and the wet/dry weight were assessed. The total protein and neutrophil elastase concentrations and the neutrophil and macrophage counts in bronchoalveolar lavage fluid (BALF) were evaluated. Proinflammatory factors in BALF and ICAM-1 and MIP-2 in serum were also tested. Furthermore, the oxidative stress response was detected, and histological injury and apoptosis were evaluated. Results: All the rats in the V, L and VL groups had significant lung injury, with the VL group exhibiting the most severe injury. Compared with the findings in the VL group, AAT significantly upregulated the PaO2/FiO2 ratio but decreased the wet/dry weight ratio and protein levels in BALF. AAT also reduced proinflammatory cytokine levels and inflammatory cell counts in BALF. Lung tissue injury and cell apoptosis were mitigated by AAT. Conclusions: AAT ameliorated VILI in ARDS rats. The protection conferred by AAT may be associated with the anti-inflammatory, antioxidative stress response and anti-apoptotic effects of AAT.
Collapse
Affiliation(s)
- Xueting Wang
- a The Second Affiliated Hospital of Harbin Medical University , Harbin , China
| | - Jing Gong
- a The Second Affiliated Hospital of Harbin Medical University , Harbin , China
| | - Jingli Zhu
- a The Second Affiliated Hospital of Harbin Medical University , Harbin , China
| | - Zhehao Jin
- a The Second Affiliated Hospital of Harbin Medical University , Harbin , China
| | - Wei Gao
- a The Second Affiliated Hospital of Harbin Medical University , Harbin , China
| |
Collapse
|
4
|
Ding X, Tong Y, Jin S, Chen Z, Li T, Billiar TR, Pitt BR, Li Q, Zhang LM. Mechanical ventilation enhances extrapulmonary sepsis-induced lung injury: role of WISP1-αvβ5 integrin pathway in TLR4-mediated inflammation and injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2018; 22:302. [PMID: 30445996 PMCID: PMC6240278 DOI: 10.1186/s13054-018-2237-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 10/15/2018] [Indexed: 12/19/2022]
Abstract
Background High tidal volume ventilation of healthy lungs or exacerbation of existing acute lung injury (ALI) by more moderate mechanical ventilation (MTV) produces ventilator-induced lung injury. It is less clear whether extrapulmonary sepsis sensitizes the lung to MTV. Methods We used a two-hit model of cecal ligation and puncture (CLP) followed 12 h later by MTV (10 ml/kg; 6 h) to determine whether otherwise noninjurious MTV enhances CLP-induced ALI by contrasting wildtype and TLR4−/− mice with respect to: alveolar-capillary permeability, histopathology and intrapulmonary levels of WNT-inducible secreted protein 1 (WISP1) and integrin β5; plasma levels of cytokines and chemokines (TNF-α, IL-6, MIP-2, MCP-1) and intrapulmonary neutrophil infiltration; and other inflammatory signaling via intrapulmonary activation of JNK, p38 and ERK. A separate cohort of mice was pretreated with intratracheal neutralizing antibodies to WISP1, integrin β5 or IgG as control and the presented phenotyping repeated in a two-hit model; there were 10 mice per group in these first three experiments. Also, isolated peritoneal macrophages (PM) from wildtype and TLR4−/−, MyD88−/− and TRIF−/− mice were used to identify a WISP1–TLR4–integrin β5 pathway; and the requisite role of integrin β5 in WISP1-induced cytokine and chemokine production in LPS-primed PM was examined by siRNA treatment. Results MTV, that in itself did not cause ALI, exacerbated increases in alveolar-capillary permeability, histopathologic scoring and indices of pulmonary inflammation in mice that previously underwent CLP; the effects of this two-hit model were abrogated in TLR4−/− mice. Attendant with these findings was a significant increase in intrapulmonary WISP1 and integrin β5 in the two-hit model. Anti-WISP1 or anti-integrin β5 antibodies partially inhibited the two-hit phenotype. In PM, activation of TLR4 led to an increase in integrin β5 expression that was MyD88 and NF-κB dependent. Recombinant WISP1 increased LPS-induced cytokine release in PM that was inhibited by silencing either TLR4 or integrin β5. Conclusions These data show for the first time that otherwise noninjurious mechanical ventilation can exacerbate ALI due to extrapulmonary sepsis underscoring a potential interactive contribution of common events (sepsis and mechanical ventilation) in critical care, and that a WISP1–TLR4–integrin β5 pathway contributes to this phenomenon. Electronic supplementary material The online version of this article (10.1186/s13054-018-2237-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xibing Ding
- Department of Anesthesiology, East Hospital, Tongji University School of Medicine, 150 Jimo Road, Pudong, Shanghai, China.,Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Anesthesiology, University of Pittsburgh School of Medicine, 200 Lothrop St. UPMC MUH N467, Pittsburgh, 15213, PA, USA.,Department of Anesthesiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yao Tong
- Department of Anesthesiology, East Hospital, Tongji University School of Medicine, 150 Jimo Road, Pudong, Shanghai, China
| | - Shuqing Jin
- Department of Anesthesiology, East Hospital, Tongji University School of Medicine, 150 Jimo Road, Pudong, Shanghai, China.,Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Zhixia Chen
- Department of Anesthesiology, East Hospital, Tongji University School of Medicine, 150 Jimo Road, Pudong, Shanghai, China
| | - Tunliang Li
- Department of Anesthesiology, Xiangya 3rd Hospital, Central South University, Hunan, China.,Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Timothy R Billiar
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Bruce R Pitt
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School Public Health, Pittsburgh, PA, USA
| | - Quan Li
- Department of Anesthesiology, East Hospital, Tongji University School of Medicine, 150 Jimo Road, Pudong, Shanghai, China. .,Department of Anesthesiology, Cancer Hospital Chinese Academy of Medical Sciences, Shenzhen, China.
| | - Li-Ming Zhang
- Department of Anesthesiology, University of Pittsburgh School of Medicine, 200 Lothrop St. UPMC MUH N467, Pittsburgh, 15213, PA, USA.
| |
Collapse
|
5
|
Desflurane Attenuates Ventilator-Induced Lung Injury in Rats with Acute Respiratory Distress Syndrome. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7507314. [PMID: 29670906 PMCID: PMC5833253 DOI: 10.1155/2018/7507314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/25/2017] [Indexed: 11/18/2022]
Abstract
Ventilator-induced lung injury aggravates the existing lung injury. This study investigated the effect of desflurane on VILI in a rat model of acute respiratory distress syndrome. Forty-eight rats were randomized into a sham (S) group, control (C) group, lipopolysaccharide/ventilation (LV) group, lipopolysaccharide/ventilation/desflurane (LVD) group, or lipopolysaccharide/low ventilation with and without desflurane (LLV and LLVD) groups. Rats in the S group received anesthesia only. Rats in the LV and LVD groups received lipopolysaccharide and were ventilated with a high tidal volume. Rats in LLV and LLVD groups were treated as the LV and LVD groups and ventilated with a low tidal volume. PaO2/FiO2, lung wet-to-dry weight ratios, concentrations of inflammatory factors in serum and BALF, histopathologic analysis of lung tissue, and levels of nuclear factor- (NF-) κB protein in lung tissue were investigated. PaO2/FiO2 was significantly increased by desflurane. Total cell count, macrophages, and neutrophils in BALF and proinflammatory factors in BALF and serum were significantly decreased by desflurane, while IL-10 was increased. The histopathological changes and levels of NF-κB protein in lung tissue were decreased by desflurane. The results indicated that desflurane ameliorated VILI in a rat model of acute respiratory distress syndrome.
Collapse
|
6
|
Gao W, Ju YN. Budesonide Attenuates Ventilator-induced Lung Injury in a Rat Model of Inflammatory Acute Respiratory Distress Syndrome. Arch Med Res 2017; 47:275-84. [PMID: 27664487 DOI: 10.1016/j.arcmed.2016.07.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 07/22/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND AIMS Patients with acute respiratory distress syndrome (ARDS) are particularly susceptible to ventilator-induced lung injury (VILI). This study investigated the effect of budesonide on VILI in a rat model of inflammatory ARDS. METHODS Forty eight rats were randomized into three groups (n = 16 each): sham group (S), endotoxin/ventilation group (LV), endotoxin/ventilation/budesonide group (LVB). Rats in the S group received anesthesia only. Rats in the LV and LVB groups received endotoxin to simulate ARDS and were mechanically ventilated for 4 h (tidal volume 30 mL/kg). Rats in the LVB group received budesonide 1 mg, and rats in the LV group received saline in airway. PaO2/FiO2, lung wet-to-dry weight ratios, inflammatory factors in serum and bronchoalveolar lavage fluid (BALF), histopathologic analysis of lung tissue, and survival were examined. RESULTS PaO2/FiO2 was significantly increased in rats in the LVB group compared to the LV group. Total cell count, macrophages, and neutrophils in BALF, and levels of intercellular adhesion molecule (ICAM)-1, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-8 in BALF and serum were significantly decreased in rats in the LVB group compared to the LV group, whereas levels of IL-10 in BALF and serum were significantly increased. Histopathological changes of lung injury and apoptosis were reduced, and survival was increased in rats in the LVB group compared to the LV group. CONCLUSIONS Budesonide ameliorated VILI in a rat model of inflammatory ARDS.
Collapse
Affiliation(s)
- Wei Gao
- Department of Anesthesiology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Ying-Nan Ju
- Department of Intensive Care Unit, The Cancer Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China.
| |
Collapse
|
7
|
Mechanical Ventilation Induces an Inflammatory Response in Preinjured Lungs in Late Phase of Sepsis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:364020. [PMID: 26161235 PMCID: PMC4487711 DOI: 10.1155/2015/364020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/09/2014] [Accepted: 10/16/2014] [Indexed: 01/09/2023]
Abstract
Mechanical ventilation (MV) may amplify the lung-specific inflammatory response in preinjured lungs by elevating cytokine release and augmenting damage to the alveolar integrity. In this study, we test the hypothesis that MV exerts different negative impacts on inflammatory response at different time points of postlung injury. Basic lung injury was induced by cecal ligation and puncture (CLP) surgery in rats. Physiological indexes including blood gases were monitored during MV and samples were assessed following each experiment. Low VT (tidal volume) MV caused a slight increase in cytokine release and tissue damage at day 1 and day 4 after sepsis induced lung injury, while cytokine release from the lungs in the two moderately ventilated VT groups was amplified. Interestingly, in the two groups where rats received low VT MV, we found that infiltration of inflammatory cells was only profound at day 4 after CLP. Marked elevation of protein leakage indicated a compromise in alveolar integrity in rats that received moderate VT MV at day 4 following CLP, correlating with architectural damage to the alveoli. Our study indicates that preinjured lungs are more sensitive to mechanical MV at later phases of sepsis, and this situation may be a result of differing immune status.
Collapse
|
8
|
High-frequency percussive ventilation and initial biomarker levels of lung injury in patients with minor burns after smoke inhalation injury. Burns 2015; 41:65-70. [DOI: 10.1016/j.burns.2014.05.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 05/06/2014] [Accepted: 05/09/2014] [Indexed: 11/23/2022]
|
9
|
Yehya N, Xin Y, Oquendo Y, Cereda M, Rizi RR, Margulies SS. Cecal ligation and puncture accelerates development of ventilator-induced lung injury. Am J Physiol Lung Cell Mol Physiol 2014; 308:L443-51. [PMID: 25550313 DOI: 10.1152/ajplung.00312.2014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Sepsis is a leading cause of respiratory failure requiring mechanical ventilation, but the interaction between sepsis and ventilation is unclear. While prior studies demonstrated a priming role with endotoxin, actual septic animal models have yielded conflicting results regarding the role of preceding sepsis on development of subsequent ventilator-induced lung injury (VILI). Using a rat cecal ligation and puncture (CLP) model of sepsis and subsequent injurious ventilation, we sought to determine if sepsis affects development of VILI. Adult male Sprague-Dawley rats were subject to CLP or sham operation and, after 12 h, underwent injurious mechanical ventilation (tidal volume 30 ml/kg, positive end-expiratory pressure 0 cmH2O) for either 0, 60, or 120 min. Biochemical and physiological measurements, as well as computed tomography, were used to assess injury at 0, 60, and 120 min of ventilation. Before ventilation, CLP rats had higher levels of alveolar neutrophils and interleukin-1β. After 60 min of ventilation, CLP rats had worse injury as evidenced by increased alveolar inflammation, permeability, respiratory static compliance, edema, oxygenation, and computed tomography. By 120 min, CLP and sham rats had comparable levels of lung injury as assessed by many, but not all, of these metrics. CLP rats had an accelerated and worse loss of end-expiratory lung volume relative to sham, and consistently higher levels of alveolar interleukin-1β. Loss of aeration and progression of edema was more pronounced in dependent lung regions. We conclude that CLP initiated pulmonary inflammation in rats, and accelerated the development of subsequent VILI.
Collapse
Affiliation(s)
- Nadir Yehya
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania;
| | - Yi Xin
- Department of Radiology, Hospital of the University of Pennsylvania, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Yousi Oquendo
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Maurizio Cereda
- Department of Radiology, Hospital of the University of Pennsylvania, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; and Department of Anesthesiology and Critical Care Medicine, Hospital of the University of Pennsylvania, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rahim R Rizi
- Department of Radiology, Hospital of the University of Pennsylvania, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Susan S Margulies
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania
| |
Collapse
|
10
|
Late administration of surfactant replacement therapy increases surfactant protein-B content: a randomized pilot study. Pediatr Res 2012; 72:613-9. [PMID: 23037875 PMCID: PMC3548137 DOI: 10.1038/pr.2012.136] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Surfactant dysfunction may contribute to the development of bronchopulmonary dysplasia (BPD) in persistently ventilated preterm infants. We conducted a multicenter randomized, blinded, pilot study to assess the safety and efficacy of late administration of doses of a surfactant protein-B (SP-B)-containing surfactant (calfactant) in combination with prolonged inhaled nitric oxide (iNO) in infants ≤1,000 g birth weight (BW). METHODS We randomized 85 preterm infants ventilated at 7-14 d after birth to receive either late administration of surfactant (up to 5 doses) plus prolonged iNO or iNO alone. Large aggregate surfactant was isolated from daily tracheal aspirates (TAs) for measurement of SP-B content, total protein, and phospholipid (PL). RESULTS Late administration of surfactant had minimal acute adverse effects. Clinical status as well as surfactant recovery and SP-B content in tracheal aspirate were transiently improved as compared to the controls; these effects waned after 1 d. The change in SP-B content with surfactant dosing was positively correlated with SP-B levels during treatment (r = 0.50, P = 0.02). CONCLUSION Low SP-B values increased with calfactant administration, but the relationship of this response to SP-B levels suggests that degradation is a contributing mechanism for SP-B deficiency and surfactant dysfunction. We conclude that late therapy with surfactant in combination with iNO is safe and transiently increases surfactant SP-B content, possibly leading to improved short- and long-term respiratory outcomes.
Collapse
|
11
|
Airway response to acute mechanical stress in a human bronchial model of stretch. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2011; 15:R208. [PMID: 21914176 PMCID: PMC3334752 DOI: 10.1186/cc10443] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Revised: 08/11/2011] [Accepted: 09/13/2011] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Lung inflation may have deleterious effects on the alveoli during mechanical ventilation. However, the consequences of stretch during excessive lung inflation on basal tone and responsiveness of human bronchi are unknown. This study was undertaken to devise an experimental model of acute mechanical stretch in isolated human bronchi and to investigate its effect on airway tone and responsiveness. METHODS Bronchi were removed from 48 thoracic surgery patients. After preparation and equilibration in an organ bath, bronchial rings were stretched for 5 min using a force (2.5 × basal tone) that corresponded to airway-inflation pressure > 30 cm H₂O. The consequences of stretch were examined by using functional experiments, analysis of organ-bath fluid, and ribonucleic acid (RNA) isolation from tissue samples. RESULTS Following removal of the applied force the airways immediately developed an increase in basal tone (P < 0.0001 vs. paired controls) that was sustained and it did so without significantly increasing responsiveness to acetylcholine. The spontaneous tone was abolished with a Rho-kinase inhibitor and epithelium removal, a leukotriene antagonist or nitric oxide synthase inhibitors reduced it, whereas indomethacin, sensory nerve inhibitors or antagonists for muscarinic, endothelin and histamine receptors had no effect. Stretch enhanced leukotriene-E4 production during the immediate spontaneous contraction of human bronchi (P < 0.05). Moreover, stretch up-regulated the early mRNA expression of genes involved in wingless-type mouse mammary tumor virus integration-site family (WNT)-signaling and Rho-kinase pathways. CONCLUSIONS Stretching human bronchi for only 5 min induces epithelial leukotriene release via nitric oxide synthase activation and provokes a myogenic response dependent on Rho-kinase and WNT-signaling pathways. From a clinical perspective, these findings highlight the response of human airway to acute mechanical stress during excessive pulmonary inflation.
Collapse
|
12
|
Lu Q, Zhang M, Girardi C, Bouhemad B, Kesecioglu J, Rouby JJ. Computed tomography assessment of exogenous surfactant-induced lung reaeration in patients with acute lung injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2010; 14:R135. [PMID: 20633284 PMCID: PMC2945105 DOI: 10.1186/cc9186] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 04/27/2010] [Accepted: 07/15/2010] [Indexed: 12/02/2022]
Abstract
Introduction Previous randomized trials failed to demonstrate a decrease in mortality of patients with acute lung injury treated by exogenous surfactant. The aim of this prospective randomized study was to evaluate the effects of exogenous porcine-derived surfactant on pulmonary reaeration and lung tissue in patients with acute lung injury and acute respiratory distress syndrome (ALI/ARDS). Methods Twenty patients with ALI/ARDS were studied (10 treated by surfactant and 10 controls) in whom a spiral thoracic computed tomography scan was acquired before (baseline), 39 hours and 7 days after the first surfactant administration. In the surfactant group, 3 doses of porcine-derived lung surfactant (200 mg/kg/dose) were instilled in both lungs at 0, 12 and 36 hours. Each instillation was followed by recruitment maneuvers. Gas and tissue volumes were measured separately in poorly/nonaerated and normally aerated lung areas before and seven days after the first surfactant administration. Surfactant-induced lung reaeration was defined as an increase in gas volume in poorly/non-aerated lung areas between day seven and baseline compared to the control group. Results At day seven, surfactant induced a significant increase in volume of gas in poorly/non-aerated lung areas (320 ± 125 ml versus 135 ± 161 ml in controls, P = 0.01) and a significant increase in volume of tissue in normally aerated lung areas (189 ± 179 ml versus -15 ± 105 ml in controls, P < 0.01). PaO2/FiO2 ratio was not different between the surfactant treated group and control group after surfactant replacement. Conclusions Intratracheal surfactant replacement induces a significant and prolonged lung reaeration. It also induces a significant increase in lung tissue in normally aerated lung areas, whose mechanisms remain to be elucidated. Trial registration NCT00742482.
Collapse
Affiliation(s)
- Qin Lu
- Multidisciplinary Intensive Care Unit, Department of Anesthesiology and Critical Care Medicine, Assistance Publique-Hôpitaux de Paris, La Pitié-Salpêtrière Hospital, UPMC Univ Paris 06, 47-83 boulevard de l'hôpital, 75013 Paris, France.
| | | | | | | | | | | |
Collapse
|
13
|
McKechnie SR, Drummond GB. Cytokines, neurokines or both? Mixed mechanisms of mechanical lung injury. J Physiol 2010; 588:1813-4. [PMID: 20516345 PMCID: PMC2901965 DOI: 10.1113/jphysiol.2010.191478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- S R McKechnie
- Adult Intensive Care Unit, John Radcliffe Hospital, Oxford, UK.
| | | |
Collapse
|
14
|
Cao G, Lee YZ, Peng R, Liu Z, Rajaram R, Calderon-Colon X, An L, Wang P, Phan T, Sultana S, Lalush DS, Lu JP, Zhou O. A dynamic micro-CT scanner based on a carbon nanotube field emission x-ray source. Phys Med Biol 2009; 54:2323-40. [PMID: 19321922 DOI: 10.1088/0031-9155/54/8/005] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Current commercial micro-CT scanners have the capability of imaging objects ex vivo with high spatial resolution, but performing in vivo micro-CT on free-breathing small animals is still challenging because their physiological motions are non-periodic and much faster than those of humans. In this paper, we present a prototype physiologically gated micro-computed tomography (micro-CT) scanner based on a carbon nanotube field emission micro-focus x-ray source. The novel x-ray source allows x-ray pulses and imaging sequences to be readily synchronized and gated to non-periodic physiological signals from small animals. The system performance is evaluated using phantoms and sacrificed and anesthetized mice. Prospective respiratory-gated micro-CT images of anesthetized free-breathing mice were collected using this scanner at 50 ms temporal resolution and 6.2 lp mm(-1) at 10% system MTF. The high spatial and temporal resolutions of the micro-CT scanner make it well suited for high-resolution imaging of free-breathing small animals.
Collapse
Affiliation(s)
- G Cao
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Ford NL, Martin EL, Lewis JF, Veldhuizen RAW, Holdsworth DW, Drangova M. Quantifying lung morphology with respiratory-gated micro-CT in a murine model of emphysema. Phys Med Biol 2009; 54:2121-30. [DOI: 10.1088/0031-9155/54/7/018] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
16
|
Wilson MR, O'Dea KP, Zhang D, Shearman AD, van Rooijen N, Takata M. Role of lung-marginated monocytes in an in vivo mouse model of ventilator-induced lung injury. Am J Respir Crit Care Med 2009; 179:914-22. [PMID: 19218195 DOI: 10.1164/rccm.200806-877oc] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
RATIONALE Recruited leukocytes play an important role in ventilator-induced lung injury, although studies have focused predominantly on neutrophils. Inflammatory subset Gr-1(high) monocytes are recruited to sites of inflammation and have been implicated in acute lung injury induced by systemic endotoxin. OBJECTIVES To investigate the recruitment and role of Gr-1(high) monocytes in an in vivo mouse model of ventilator-induced lung injury. METHODS Anesthetized mice were ventilated with low or high stretch. Flow cytometry was used to quantify monocyte subset margination to the lungs, and to assess their in situ cellular activation in response to mechanical stretch. To investigate monocyte involvement in lung injury progression, a two-hit model was used, with a subclinical dose of lipopolysaccharide (intraperitoneal) given 2 hours prior to high-stretch ventilation. In some animals, monocytes were depleted using intravenous clodronate liposomes. Development of lung injury was assessed in ventilated animals by peak inspiratory pressure and respiratory system mechanics. MEASUREMENTS AND MAIN RESULTS High-stretch ventilation induced significant pulmonary margination of Gr-1(high) but not Gr-1(low) monocytes compared with nonventilated mice. These monocytes displayed increased activation status, with higher CD11b (vs. nonventilated mice) and lower L-selectin expression (vs. low-stretch ventilation). Lipopolysaccharide challenge led to enhanced lung margination of Gr-1(high) monocytes and neutrophils, and sensitized the lungs to high stretch-induced pulmonary edema. Clodronate-liposome pretreatment depleted lung monocytes (but not neutrophils) and significantly attenuated lung injury. CONCLUSIONS High-stretch mechanical ventilation promotes pulmonary margination of activated Gr-1(high) monocytes, which play a role in the progression of ventilator-induced lung injury.
Collapse
Affiliation(s)
- Michael R Wilson
- Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea, United Kingdom
| | | | | | | | | | | |
Collapse
|
17
|
The effects of long-term conventional mechanical ventilation on the lungs of adult rats*. Crit Care Med 2008; 36:2381-7. [DOI: 10.1097/ccm.0b013e318180b65c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
18
|
Hypercapnic acidosis modulates inflammation, lung mechanics, and edema in the isolated perfused lung. J Crit Care 2007; 22:305-13. [DOI: 10.1016/j.jcrc.2006.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 12/01/2006] [Accepted: 12/15/2006] [Indexed: 11/18/2022]
|
19
|
Yang YL, Tang GJ, Wu YL, Yien HW, Lee TS, Kou YR. Exacerbation of wood smoke-induced acute lung injury by mechanical ventilation using moderately high tidal volume in mice. Respir Physiol Neurobiol 2007; 160:99-108. [PMID: 17964866 DOI: 10.1016/j.resp.2007.09.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 09/03/2007] [Accepted: 09/10/2007] [Indexed: 11/27/2022]
Abstract
We investigated the effects of mechanical ventilation with a moderately high tidal volume (VT) on acute lung injury (ALI) induced by wood smoke inhalation in anesthetized mice. Animals received challenges of air, 30 breaths of smoke (30SM) or 60 breaths of smoke (60SM) and were then ventilated with a VT of 10 ml/kg (10VT) or 16 ml/kg (16VT). After 4-h mechanical ventilation, the bronchoalveolar-capillary permeability, pulmonary infiltration of inflammatory cells, total lung injury score and pulmonary expressions of interleukin-1beta and macrophage inflammatory protein-2 mRNA and proteins in the 30SM+16VT and 60SM+16VT groups were greater than those in the 30SM+10VT and 60SM+10VT groups, respectively. Additionally, the wet/dry weight ratio of lung tissues and lung epithelial cell apoptosis in the 60SM+16VT group were greater than those in the 60SM+10VT group. These differences between the 16VT and 10VT groups were not seen in animals with air challenge. Thus, mechanical ventilation with a moderately high VT in mice exacerbates ALI induced by wood smoke inhalation.
Collapse
Affiliation(s)
- You-Lan Yang
- Department of Physiology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | | | | | | | | | | |
Collapse
|
20
|
Ford NL, Wheatley AR, Holdsworth DW, Drangova M. Optimization of a retrospective technique for respiratory-gated high speed micro-CT of free-breathing rodents. Phys Med Biol 2007; 52:5749-69. [PMID: 17881798 DOI: 10.1088/0031-9155/52/19/002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The objective of this study was to develop a technique for dynamic respiratory imaging using retrospectively gated high-speed micro-CT imaging of free-breathing mice. Free-breathing C57Bl6 mice were scanned using a dynamic micro-CT scanner, comprising a flat-panel detector mounted on a slip-ring gantry. Projection images were acquired over ten complete gantry rotations in 50 s, while monitoring the respiratory motion in synchrony with projection-image acquisition. Projection images belonging to a selected respiratory phase were retrospectively identified and used for 3D reconstruction. The effect of using fewer gantry rotations--which influences both image quality and the ability to quantify respiratory function--was evaluated. Images reconstructed using unique projections from six or more gantry rotations produced acceptable images for quantitative analysis of lung volume, CT density, functional residual capacity and tidal volume. The functional residual capacity (0.15 +/- 0.03 mL) and tidal volumes (0.08 +/- 0.03 mL) measured in this study agree with previously reported measurements made using prospectively gated micro-CT and at higher resolution (150 microm versus 90 microm voxel spacing). Retrospectively gated micro-CT imaging of free-breathing mice enables quantitative dynamic measurement of morphological and functional parameters in the mouse models of respiratory disease, with scan times as short as 30 s, based on the acquisition of projection images over six gantry rotations.
Collapse
Affiliation(s)
- Nancy L Ford
- Department of Physics, Ryerson University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada.
| | | | | | | |
Collapse
|
21
|
Ota S, Nakamura K, Yazawa T, Kawaguchi Y, Baba Y, Kitaoka R, Morimura N, Goto T, Yamada Y, Kurahashi K. High tidal volume ventilation induces lung injury after hepatic ischemia-reperfusion. Am J Physiol Lung Cell Mol Physiol 2007; 292:L625-31. [PMID: 17056704 DOI: 10.1152/ajplung.00151.2006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ischemia-reperfusion not only damages the affected organ but also leads to remote organ injuries. Hepatic inflow interruption usually occurs during hepatic surgery. To investigate the influence of liver ischemia-reperfusion on lung injury and to determine the contribution of tidal volume settings on liver ischemia-reperfusion-induced lung injury, we studied anesthetized and mechanically ventilated rats in which the hepatic inflow was transiently interrupted twice for 15 min. Two tidal volumes, 6 ml/kg as a low tidal volume (IR-LT) and 24 ml/kg as a high tidal volume (IR-HT), were assessed after liver ischemia-reperfusion, as well as after a sham operation, 6 ml/kg (NC-LT) and 24 ml/kg (NC-HT). Both the IR-HT and IR-LT groups had a gradual decline in the systemic blood pressure and a significant increase in plasma TNF-α concentrations. Of the four groups, only the IR-HT group developed lung injury, as assessed by an increase in the lung wet-to-dry weight ratio, the presence of significant histopathological changes, such as perivascular edema and intravascular leukocyte aggregation, and an increase in the bronchoalveolar lavage fluid TNF-α concentration. Furthermore, only in the IR-HT group was airway pressure increased significantly during the 6-h reperfusion period. These findings suggest that liver ischemia-reperfusion caused systemic inflammation and that lung injury is triggered when high tidal volume ventilation follows liver ischemia-reperfusion.
Collapse
Affiliation(s)
- Shuhei Ota
- Department of Anesthesiology and Critical Care Medicine, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Abstract
Acute respiratory failure is manifested clinically as a patient with variable degrees of respiratory distress, but characteristically an abnormal arterial blood partial pressure of oxygen or carbon dioxide. The application of mechanical ventilation in this setting can be life-saving. An emerging body of clinical and basic research, however, has highlighted the potential adverse effects of positive pressure ventilation. Clinicians involved with the care of critically ill patients must recognize and seek to prevent these complications using lung-protective ventilation strategies. This article discusses the basic concepts of mechanical ventilation, reviews the categories of ventilator-associated lung injury, and discusses current strategies for the recognition and prevention of these adverse effects in the application of mechanical ventilation.
Collapse
Affiliation(s)
- Michael Donahoe
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, 3459 Fifth Avenue, 628 NW, Pittsburgh, PA 15213, USA.
| |
Collapse
|
23
|
Ford NL, Martin EL, Lewis JF, Veldhuizen RAW, Drangova M, Holdsworth DW. In vivo characterization of lung morphology and function in anesthetized free-breathing mice using micro-computed tomography. J Appl Physiol (1985) 2007; 102:2046-55. [PMID: 17255374 DOI: 10.1152/japplphysiol.00629.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lung morphology and function in human subjects can be monitored with computed tomography (CT). Because many human respiratory diseases are routinely modeled in rodents, a means of monitoring the changes in the structure and function of the rodent lung is desired. High-resolution images of the rodent lung can be attained with specialized micro-CT equipment, which provides a means of monitoring rodent models of lung disease noninvasively with a clinically relevant method. Previous studies have shown respiratory-gated images of intubated and respirated mice. Although the image quality and resolution are sufficient in these studies to make quantitative measurements, these measurements of lung structure will depend on the settings of the ventilator and not on the respiratory mechanics of the individual animals. In addition, intubation and ventilation can have unnatural effects on the respiratory dynamics of the animal, because the airway pressure, tidal volume, and respiratory rate are selected by the operator. In these experiments, important information about the symptoms of the respiratory disease being studied may be missed because the respiration is forced to conform to the ventilator settings. In this study, we implement a method of respiratory-gated micro-CT for use with anesthetized free-breathing rodents. From the micro-CT images, quantitative analysis of the structure of the lungs of healthy unconscious mice was performed to obtain airway diameters, lung and airway volumes, and CT densities at end expiration and during inspiration. Because the animals were free breathing, we were able to calculate tidal volume (0.09 +/- 0.03 ml) and functional residual capacity (0.16 +/- 0.03 ml).
Collapse
Affiliation(s)
- N L Ford
- Robarts Research Institute, London, ON, Canada N6A5K8.
| | | | | | | | | | | |
Collapse
|
24
|
Cepkova M, Brady S, Sapru A, Matthay MA, Church G. Biological markers of lung injury before and after the institution of positive pressure ventilation in patients with acute lung injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2007; 10:R126. [PMID: 16956410 PMCID: PMC1751077 DOI: 10.1186/cc5037] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 08/14/2006] [Accepted: 09/06/2006] [Indexed: 12/28/2022]
Abstract
BACKGROUND Several biological markers of lung injury are predictors of morbidity and mortality in patients with acute lung injury (ALI). The low tidal volume lung-protective ventilation strategy is associated with a significant decrease in plasma biomarker levels compared to the high tidal volume ventilation strategy. The primary objective of this study was to test whether the institution of lung-protective positive pressure ventilation in spontaneously ventilating patients with ALI exacerbates pre-existing lung injury by using measurements of biomarkers of lung injury before and after intubation. MATERIALS AND METHODS A prospective observational cohort study was conducted in the intensive care unit of a tertiary care university hospital. Twenty-five intubated, mechanically ventilated patients with ALI were enrolled. Physiologic data and serum samples were collected within 6 hours before intubation and at two different time points within the first 24 hours after intubation to measure the concentration of interleukin (IL)-6, IL-8, intercellular adhesion molecule 1 (ICAM-1), and von Willebrand factor (vWF). The differences in biomarker levels before and after intubation were analysed using repeated measures analysis of variance and a paired t test with correction for multiple comparisons. RESULTS Before endotracheal intubation, all of the biological markers (IL-8, IL-6, ICAM-1, and vWF) were elevated in the spontaneously breathing patients with ALI. After intubation and the institution of positive pressure ventilation (tidal volume 7 to 8 ml/kg per ideal body weight), none of the biological markers was significantly increased at either an early (3 +/- 2 hours) or later (21 +/- 5 hours) time point. However, the levels of IL-8 were significantly decreased at the later time point (21 +/- 5 hours) after intubation. During the 24-hour period after intubation, the PaO2/FiO2 (partial pressure of arterial oxygen/fraction of the inspired oxygen) ratio significantly increased and the plateau airway pressure significantly decreased. CONCLUSION Levels of IL-8, IL-6, vWF, and ICAM-1 are elevated in spontaneously ventilating patients with ALI prior to endotracheal intubation. The institution of a lung-protective ventilation strategy with positive pressure ventilation does not further increase the levels of biological markers of lung injury. The results suggest that the institution of a lung-protective positive pressure ventilation strategy does not worsen the pre-existing lung injury in most patients with ALI.
Collapse
Affiliation(s)
- Magda Cepkova
- The Cardiovascular Research Institute and the Departments of Medicine and Anesthesia, University of California, San Francisco, 505 Parnassus Avenue, M917, San Francisco, CA 94143-0624, USA
| | - Sandra Brady
- The Cardiovascular Research Institute and the Departments of Medicine and Anesthesia, University of California, San Francisco, 505 Parnassus Avenue, M917, San Francisco, CA 94143-0624, USA
| | - Anil Sapru
- The Cardiovascular Research Institute and the Departments of Medicine and Anesthesia, University of California, San Francisco, 505 Parnassus Avenue, M917, San Francisco, CA 94143-0624, USA
| | - Michael A Matthay
- The Cardiovascular Research Institute and the Departments of Medicine and Anesthesia, University of California, San Francisco, 505 Parnassus Avenue, M917, San Francisco, CA 94143-0624, USA
| | - Gwynne Church
- The Cardiovascular Research Institute and the Departments of Medicine and Anesthesia, University of California, San Francisco, 505 Parnassus Avenue, M917, San Francisco, CA 94143-0624, USA
| |
Collapse
|
25
|
Thomas RA, Norman JC, Huynh TT, Williams B, Bolton SJ, Wardlaw AJ. Mechanical stretch has contrasting effects on mediator release from bronchial epithelial cells, with a rho-kinase-dependent component to the mechanotransduction pathway. Respir Med 2006; 100:1588-97. [PMID: 16469490 DOI: 10.1016/j.rmed.2005.12.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
INTRODUCTION In vivo, the airway epithelium stretches and relaxes with each respiratory cycle, but little is known about the effect this pattern of elongation and relaxation has on bronchial epithelial cells. We have used a model of cell deformation to measure the effect of stretch on inflammatory cytokine release by the BEAS 2B cell line, and to examine the method of mechanotransduction in these cells. METHODS BEAS 2B cells were cyclically stretched using the Flexercell system. IL-8 and RANTES protein and RNA levels were measured after different elongations, rates and duration of stretch. An inhibitor of Rho (Ras Homologous)-associated kinases was used, to assess the effect of blocking downstream of integrin signalling. Immunofluorescent staining of paxillin was used to study the effect of stretch on the distribution of focal contacts and the organisation of the actin cytoskeleton. RESULTS IL-8 release by BEAS 2B cells was increased by cytokine stimulation and stretch, whereas RANTES levels in the cell supernatant decreased after stretch in a dose-, time- and rate-dependent manner. Thirty percent elongation at 20 cycles/min for 24h increased IL-8 levels by over 100% (P < 0.01). Blocking rho kinase using Y-27632 inhibited the effect of stretch on IL-8 release by the BEAS 2B cells. Immunofluorescent staining demonstrated that stretch caused dramatic disassembly of focal adhesions and resulted in the redistribution of paxillin to the peri-nuclear region. CONCLUSION This study demonstrates a marked effect of stretch on bronchial epithelial cell function. We propose that stretch modulates epithelial cell function via the activation of rho kinases. The observation that stretch promotes focal adhesion disassembly suggests a mechanism whereby focal adhesion turnover (coordination of assembly and disassembly) is essential for mechanotransduction in bronchial epithelial cells.
Collapse
Affiliation(s)
- R A Thomas
- Institute for Lung Health, University of Leicester, UK
| | | | | | | | | | | |
Collapse
|
26
|
Levine GK, Deutschman CS, Helfaer MA, Margulies SS. Sepsis-induced lung injury in rats increases alveolar epithelial vulnerability to stretch. Crit Care Med 2006; 34:1746-51. [PMID: 16625134 DOI: 10.1097/01.ccm.0000218813.77367.e2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Previous in vitro models have shown that cellular deformation causes dose-dependent injury and death in healthy rat alveolar epithelial cells (AECs). We compared the viability of AECs from septic rats with those from nonseptic rats after 1 hr of cyclic equibiaxial stretch. We hypothesized that sepsis would increase stretch-induced cell death. DESIGN Laboratory investigation. SETTING University research laboratory. SUBJECTS Thirty-seven male Sprague-Dawley rats weighing 240-260 g. INTERVENTIONS Anesthetized rats were subjected to cecal ligation and double puncture (2CLP) or sham laparotomy without cecal ligation or puncture (sham). After 24 or 48 hrs, AECs were isolated, seeded in custom wells, and maintained in culture for 48 hrs before study. AECs were stretched cyclically (15/min) to a 0%, 12%, 25%, or 37% change in surface area (DeltaSA) for 1 hr. Cell viability, phenotypic markers, and nuclear factor-kappaB intracellular localization were assessed using fluorescent immunocytochemistry. MEASUREMENTS AND MAIN RESULTS Phase and fluorescent images were evaluated for all studies. Response to stretch was the same at 24 and 48 hrs after 2CLP. Relative to sham, 2CLP significantly increased cell death at 25 and 37% DeltaSA (p<.003, analysis of variance). Relative to sham, 2CLP did not alter expression of type I or type II phenotypic markers. Nuclear factor-kappaB within the nuclear compartment was observed after 2CLP in unstretched cells and after 1 hr of cyclic stretch at 37% DeltaSA. In sham, nuclear factor-kappaB within the nuclear compartment was seen only after stretch. CONCLUSIONS AECs isolated from septic rats are more vulnerable to mechanical deformation injury than AECs from nonseptic animals.
Collapse
Affiliation(s)
- Glenn K Levine
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, and Department of Anesthesia, University of Pennsylvania School of Medicine, Philadelphia 19104-6392, USA
| | | | | | | |
Collapse
|
27
|
|
28
|
Brackenbury AM, McCaig LA, Yao LJ, Veldhuizen RAW, Lewis JF. Host response to intratracheally instilled bacteria in ventilated and nonventilated rats. Crit Care Med 2004; 32:2502-7. [PMID: 15599158 DOI: 10.1097/01.ccm.0000148010.08296.9a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Pneumonia occurs in approximately 7% of hospitalized patients. Susceptibility to certain bacteria such as Pseudomonas aeruginosa increases in critically ill patients, particularly those requiring mechanical ventilation. Previous studies investigating this susceptibility have used injurious modes of ventilation. The objective of this study was to evaluate the host's response to intratracheal instillation of P. aeruginosa in the setting of noninjurious mechanical ventilation and compare this with normal, spontaneously breathing animals receiving bacteria. DESIGN Randomized, controlled in vivo animal study. SETTING Research laboratory at a university-affiliated institution. SUBJECTS Adult male Sprague-Dawley rats. INTERVENTIONS Rats were randomized into four groups: spontaneously breathing given saline, spontaneously breathing given bacteria, mechanically ventilated given saline, and mechanically ventilated given bacteria. The ventilation strategy used involved low stretch (tidal volume of 8 mL/kg) with a positive end-expiratory pressure of 5 cm H2O. MEASUREMENTS AND MAIN RESULTS Lung compliance, bacterial recovery, surfactant, total cells, and cytokine concentrations in the lung lavage were analyzed after 4 hrs. Results showed that neither ventilation nor bacteria alone altered lung function, although the combination of ventilation and Pseudomonas significantly decreased arterial oxygenation and lung compliance. Increases in lavage cell counts, cytokines, and surfactant were observed in both groups administered bacteria compared with animals given saline. However, there were no significant differences in bacterial recovery, cell counts, cytokines, and surfactant measurements in the groups given bacteria. CONCLUSIONS These data suggest that bacterial instillation with low-stretch ventilation had a significant effect on lung function but did not alter the inflammatory response to a bacterial challenge over this time course compared with spontaneously breathing animals.
Collapse
Affiliation(s)
- Angela M Brackenbury
- Department of Medicine, St. Joseph's Health Care Centre, London, Ontario, Canada
| | | | | | | | | |
Collapse
|
29
|
Yoshikawa S, King JA, Lausch RN, Penton AM, Eyal FG, Parker JC. Acute ventilator-induced vascular permeability and cytokine responses in isolated and in situ mouse lungs. J Appl Physiol (1985) 2004; 97:2190-9. [PMID: 15531572 DOI: 10.1152/japplphysiol.00324.2004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To determine the influence of experimental model and strain differences on the relationship of vascular permeability to inflammatory cytokine production after high peak inflation pressure (PIP) ventilation, we used isolated perfused mouse lung and intact mouse preparations of Balb/c and B6/129 mice ventilated at high and low PIP. Filtration coefficients in isolated lungs and bronchoalveolar lavage (BAL) albumin in intact mice increased within 20–30 min after initiation of high PIP in isolated Balb/c lungs and intact Balb/c, B6/129 wild-type, and p55 and p75 tumor necrosis factor (TNF) dual-receptor null mice. In contrast, the cytokine response was delayed and variable compared with the permeability response. In isolated Balb/c lungs ventilated with 25–27 cmH2O PIP, TNF-α, interleukin (IL)-1β, IL-1α, macrophage inflammatory protein (MIP)-2, and IL-6 concentrations in perfusate were markedly increased in perfusate at 2 and 4 h, but only MIP-2 was detectable in intact Balb/c mice using the same PIP. In intact wild-type and TNF dual-receptor null mice with ventilation at 45 cmH2O PIP, the MIP-2 and IL-6 levels in BAL were significantly increased after 2 h in both groups, but there were no differences between groups in the BAL albumin and cytokine concentrations or in lung wet-to-dry weight ratios. TNF-α was not be detected in BAL fluids in any group of intact mice. These results suggest that the alveolar hyperpermeability induced by high PIP ventilation occurs very rapidly and is initially independent of TNF-α participation and unlikely to depend on MIP-2 or IL-6.
Collapse
Affiliation(s)
- S Yoshikawa
- Dept. of Physiology, College of Medicine, University of South Alabama, Mobile, AL 36688, USA
| | | | | | | | | | | |
Collapse
|
30
|
Wilson MR, Choudhury S, Takata M. Pulmonary inflammation induced by high-stretch ventilation is mediated by tumor necrosis factor signaling in mice. Am J Physiol Lung Cell Mol Physiol 2004; 288:L599-607. [PMID: 15489373 DOI: 10.1152/ajplung.00304.2004] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although high-stretch mechanical ventilation has been demonstrated to induce lung inflammation, the roles of soluble mediators, in particular TNF, remain controversial. We have previously shown in mice that high-stretch ventilation, in the absence of preceding lung injury, induces expression of bioactive TNF in lung lavage fluid early in the course of injury, but the biological significance of this, if any, has yet to be determined. We therefore investigated the pulmonary inflammatory response to a transient period of high-stretch ventilation in anesthetized mice lacking TNF receptors and mice treated with anti-TNF antibodies. A standardized stretch-induced lung injury (assessed by lung mechanics, blood gases, and lavage protein content), followed by noninjurious low-stretch ventilation for 3 h, produced significant alveolar neutrophil infiltration in wild-type mice. However, neutrophil recruitment was substantially attenuated in TNF receptor double knockout mice and in wild-type mice treated with intratracheal anti-TNF antibody. This attenuation was not associated with decreased concentrations of neutrophil attractant CXC chemokines (macrophage inflammatory protein-2 and keratinocyte-derived chemokine) in lavage fluid. In contrast to intratracheal antibody, intravenous anti-TNF antibody did not reduce neutrophil infiltration, suggesting that the role of TNF signaling is localized within the alveolar space and does not require decompartmentalization of TNF into the circulation. These findings provide the first direct evidence that pulmonary inflammation induced by high-stretch ventilation without underlying lung injury possesses a significant TNF-dependent component. The results suggest a potential for regional anti-TNF treatment in attenuating stretch-induced pulmonary inflammation.
Collapse
Affiliation(s)
- Michael R Wilson
- Department of Anaesthetics and Intensive Care, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, United Kingdom
| | | | | |
Collapse
|
31
|
Martinez F, Lewis J, Copland I, Engelberts D, Kavanagh BP, Post M, Schurch S, Belik J. Mechanical ventilation effect on surfactant content, function, and lung compliance in the newborn rat. Pediatr Res 2004; 56:19-25. [PMID: 15128929 DOI: 10.1203/01.pdr.0000128980.82797.29] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Studies of ventilator-associated lung injury in adult experimental animal models have documented that high tidal volume (TV) results in lung injury characterized by impaired compliance and dysfunctional surfactant. Yet, there is evidence that, in neonates, ventilation with a higher than physiologic TV leads to improved lung compliance. The purpose of our study was to evaluate how lung compliance and surfactant was altered by high TV ventilation in the neonate. We utilized a new model (mechanically air-ventilated newborn rats, 4-8 d old), and used 40 or 10 mL/kg TV strategies. Age-matched nonventilated animals served as controls. In all animals, dynamic compliance progressively increased after initiation of mechanical ventilation and was significantly greater than basal values after 60 min (p < 0.01). Lung lavage total surfactant with both TV strategies (p < 0.05) and the large aggregate fraction (only in TV = 40 mL/kg; p < 0.01) were significantly increased by 60 min of mechanical ventilation, compared with control animals. Ventilation with 40 mL/kg TV for 60 min adversely affected the lung surfactant surface-tension lowering properties (p < 0.01). After 180 min of ventilation with 40 mL/kg TV, the lung total surfactant content and dynamic compliance values were no longer distinct from the nonventilated animals' values. We conclude that, in the newborn rat, mechanical ventilation with a higher than physiologic TV increases alveolar surfactant content and, over time, alters its biophysical properties, thus promoting an initial but transient improvement in lung compliance.
Collapse
Affiliation(s)
- Francisco Martinez
- Department of Pediatics, University of Toronto, Hospital for Sick Children, Toronto, ON, M5G 1X8, Canada
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Dolinay T, Szilasi M, Liu M, Choi AMK. Inhaled carbon monoxide confers antiinflammatory effects against ventilator-induced lung injury. Am J Respir Crit Care Med 2004; 170:613-20. [PMID: 15142867 DOI: 10.1164/rccm.200401-023oc] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Ventilator-induced lung injury (VILI) is a major cause of morbidity and mortality in intensive care units. The stress-inducible gene product, heme oxygenase-1, and carbon monoxide (CO), a major by-product of heme oxygenase catalysis of heme, have been shown to confer potent antiinflammatory effects in models of tissue and cellular injury. In this study, we observed increased expression of heme oxygenase-1 mRNA and protein in a rat model of VILI. To assess the physiologic function of heme oxygenase-1 induction in VILI, we determined whether low concentration of inhaled CO could serve to protect the lung against VILI. Low concentration of inhaled CO significantly reduced tumor necrosis factor-alpha levels and total cell count in lavage fluid, while simultaneously elevating levels of antiinflammatory interleukin-10 levels. To better characterize the mechanism of CO-mediated antiinflammatory effects, we examined key signaling pathways, which may mediate CO-induced antiinflammatory effects. We demonstrate that inhaled CO exerts antiinflammatory effects in VILI via the p38 mitogen-activated protein kinase pathway but independent of activator protein-1 and nuclear factor-kappaB pathways. Our data lead to a tempting speculation that inhaled CO might be useful in minimizing VILI.
Collapse
Affiliation(s)
- Tamás Dolinay
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | | | | | | |
Collapse
|
33
|
Abstract
A number of conditions, such as pneumonia, trauma, or systemic sepsis arising from the gut, may result in the acute respiratory distress syndrome (ARDS). Because of its significant morbidity and mortality, ARDS has been the focus of extensive research. One specific area of interest has been the investigation of the role of the surfactant system in the pathophysiology of this disease. Several studies have demonstrated that alterations of surfactant contribute to the lung dysfunction associated with ARDS, which has led to investigations into the use of exogenous surfactant as a therapy for this syndrome. Clinical experience with surfactant therapy has been variable owing to a number of factors including the nature of the injury at the time of treatment, the specific surfactant preparation utilized, the dose and delivery method chosen, the timing of surfactant administration over the course of the disease, and the mode of ventilation used during and after surfactant administration.
Collapse
Affiliation(s)
- James F Lewis
- Department of Medicine, Lawson Health Research Institute, University of Western Ontario, London, Ontario, Canada.
| | | |
Collapse
|
34
|
Rasaiah VPA, Malloy JL, Lewis JF, Veldhuizen RAW. Early surfactant administration protects against lung dysfunction in a mouse model of ARDS. Am J Physiol Lung Cell Mol Physiol 2003; 284:L783-90. [PMID: 12533442 DOI: 10.1152/ajplung.00391.2002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Sepsis can predispose the lung to insults such as mechanical ventilation (MV). It was hypothesized that treating the lung with exogenous surfactant early in the development of sepsis will reduce the lung dysfunction associated with MV 18 h later. Mice underwent sham or cecal ligation and perforation (CLP) surgery. Immediately after surgery, mice were either untreated or given 100 mg/kg of bovine lipid extract surfactant intratracheally. Eighteen hours later, the lungs were removed and analyzed either immediately or following ventilation ex vivo for 2 h by an "injurious" mode of ventilation (20 ml/kg, 0 cm positive end-expiratory pressure). In nonventilated lungs, exogenous surfactant had no impact on compliance or IL-6 concentrations in the lungs. In the ventilated groups, the administered surfactant had a significant protective effect on the lung dysfunction induced by MV, but only in the CLP lungs. We conclude that administration of exogenous surfactant at the time of a systemic insult can protect the lung from the damaging effects of MV 18 h later.
Collapse
Affiliation(s)
- Vijay P A Rasaiah
- Department of Physiology, Lawson Health Research Institute, University of Western Ontario, London, Ontario N6A 4V2, Canada
| | | | | | | |
Collapse
|
35
|
Abstract
The purpose of this review is to highlight areas in alveolar cell biology in which our understanding of the effects of mechanical stress have been advanced in the last year, focusing on intracellular signal transduction pathways, the surfactant system, and cell injury and repair. Mechano-transduction pathways are only now beginning to be elucidated in alveolar cells. The importance of the mitogen-activated protein kinase, G protein, and growth factor systems is emphasized. The research conducted in the last year has also stressed the importance of alveolar cell cross-talk, with surfactant exocytosis being facilitated through parathyroid hormone-related peptide and leptin and calcium in interstitial fibroblasts and endothelial cells, respectively. Finally, the importance of deformation-induced plasma membrane breaks is emphasized. Alveolar cells were found to exocytose intracellular lipid vesicles to the plasma membrane-not only to prevent cell breaks but also to reseal cell breaks. This dynamic process was a stronger determinant of cell breaks than the prestress properties of the cytoskeleton. All of these exciting findings provide further potential treatment targets for ventilator-induced lung injury.
Collapse
Affiliation(s)
- Nicholas E Vlahakis
- University of California San Francisco, Lung Biology Center, 1001 Potrero Avenue, San Francisco, 94110, USA.
| | | |
Collapse
|
36
|
Abstract
Mechanical ventilation is indispensable in support of patients with respiratory failure who are critically ill. However, use of this technique has adverse effects, including increased risk of pneumonia, impaired cardiac performance, and difficulties associated with sedation and paralysis. Moreover, application of pressure to the lung, whether positive or negative, can cause damage known as ventilator-associated lung injury (VALI). Despite difficulties in distinguishing the effects of mechanical ventilation from those of the underlying disorder, VALI greatly assists patients with the most severe form of lung injury, acute respiratory distress syndrome (ARDS). Moreover, modification of mechanical ventilation so that VALI is kept to a minimum improves survival of patients with ARDS. Here, we outline the effects of mechanical ventilation on injured lungs and explore the underlying mechanisms.
Collapse
Affiliation(s)
- Liao Pinhu
- Unit of Critical Care and National Heart and Lung Institute, London, UK
| | | | | | | |
Collapse
|
37
|
Abstract
Acute respiratory distress syndrome (ARDS) and acute lung injury are among the most frequent reasons for intensive care unit admission, accounting for approximately one-third of admissions. Mortality from ARDS has been estimated as high as 70% in some studies. Until recently, however, no targeted therapy had been found to improve patient outcome, including mortality. With the completion of the National Institutes of Health-sponsored Acute Respiratory Distress Syndrome Network low tidal volume study, clinicians now have convincing evidence that ventilation with tidal volumes lower than those conventionally used in this patient population reduces the relative risk of mortality by 21%. These data confirm the long-held suspicion that the role of mechanical ventilation for acute hypoxemic respiratory failure is more than supportive, in that mechanical ventilation can also actively contribute to lung injury. The mechanisms of the protective effects of low tidal volume ventilation in conjunction with positive end expiratory pressure are incompletely understood and are the focus of ongoing studies. The objective of the present article is to review the potential cellular mechanisms of lung injury attributable to mechanical ventilation in patients with ARDS and acute lung injury.
Collapse
Affiliation(s)
- James A Frank
- Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, Cardiovascular Research Institute, San Francisco, California, USA.
| | | |
Collapse
|