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Huang B, Iasella SV, Rathi M, Hassler J, Ciutara CO, He Z, Morse DC, Zasadzinski JA. New experiments and models to describe soluble surfactant adsorption above and below the critical micelle concentration. J Colloid Interface Sci 2025; 677:557-568. [PMID: 39111091 PMCID: PMC11461105 DOI: 10.1016/j.jcis.2024.07.204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2024] [Revised: 07/19/2024] [Accepted: 07/25/2024] [Indexed: 10/09/2024]
Abstract
HYPOTHESIS Lysopalmitoylphosphatidylcholine (LysoPC) is a soluble single-chain surfactant product of the innate immune system degradation of double-chain phospholipids. LysoPC adsorption to the air-water interface in lung alveoli can be modeled using alveolar-sized bubbles of constant surface area in a capillary pressure microtensiometer to show that adsorption is diffusion limited both below and above the critical micelle concentration (CMC). Above the CMC, a local equilibrium model is proposed in which depletion of the local monomer concentration drives dissociation of micelles in a region near the bubble surface. EXPERIMENTAL A capillary pressure microtensiometer in which a feedback loop maintains a constant bubble radius and surface area is used to measure dynamic surface tension during LysoPC adsorption. Direct numerical solution of the spherical diffusion equations, a new three parameter virial equation of state for interface thermodynamics, and a local equilibrium model of micellization above the CMC are used to accurately model the dynamic surface tension experiments both below and above the LysoPC CMC. FINDINGS LysoPC adsorption is shown to be diffusion-limited over concentrations ranging from below to well above the CMC, and to be well described by a local equilibrium model at concentrations above the CMC. Modelling the dynamic surface tension provides a reliable estimate of the micelle diffusivity near the CMC that is difficult to obtain by other methods in systems with low CMCs.
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Affiliation(s)
- Boxun Huang
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - Steven V Iasella
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - Meenal Rathi
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - Joseph Hassler
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - Clara O Ciutara
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ziwen He
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA
| | - David C Morse
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Joseph A Zasadzinski
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA.
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Fisher JM, Squires TM. Phospholipase-catalyzed degradation drives domain morphology and rheology transitions in model lung surfactant monolayers. SOFT MATTER 2024; 20:7321-7332. [PMID: 39248497 DOI: 10.1039/d4sm00306c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2024]
Abstract
Lung surfactant is inactivated in acute respiratory distress syndrome (ARDS) by a mechanism that remains unclear. Phospholipase (PLA2) plays an essential role in the normal lipid recycling processes, but is present in elevated levels in ARDS, suggesting it plays a role in ARDS pathophysiology. PLA2 hydrolyzes lipids such as DPPC-the primary component of lung surfactant-into palmitic acid (PA) and lyso-PC (LPC). Because PA co-crystallizes with DPPC to form rigid, elastic domains, we hypothesize that PLA2-catalyzed degradation establishes a stiff, heterogeneous rheology in the monolayer, and suggests a potential mechanical role in disrupting lung surfactant function during ARDS. Here we study the morphological and rheological changes of DPPC monolayers as they are degraded by PLA2 using interfacial microbutton microrheometry coupled with fluorescence microscopy. While degrading, domain morphology passes through qualitatively distinct transitions: compactification, coarsening, solidification, aggregation, network percolation, network erosion, and nucleation of PLA2-rich domains. Initially, condensed domains relax to more compact shapes, and coarsen via Ostwald ripening and coalescence up until the domains solidify, marked by a distinct roughening of domain boundaries that does not relax. Domains aggregate and eventually form a percolated network, whose elements then erode and whose connections are broken as degradation continues. The relative enzymatic activity of PLA2, set by the age of the sample, impacts the order and the duration of morphology transitions. The fresher the PLA2, the faster the overall degradation, and the earlier the onset of domain solidification: domains solidify before aggregating with fresh PLA2 samples, but aggregate and percolate before solidification with aged PLA2. Irrespective of the activity of the PLA2, all measured linear viscoelastic surface shear moduli obey the same dependence on condensed phase area fraction (log|G*| ∝ ϕ) throughout monolayer degradation. Moreover, the onset of domain solidification coincides with the time when the relative surface elasticity begins to increase.
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Affiliation(s)
- Julia M Fisher
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Todd M Squires
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
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Deng L, Wei SL, Wang L, Huang JQ. Feruloylated Oligosaccharides Prevented Influenza-Induced Lung Inflammation via the RIG-I/MAVS/TRAF3 Pathway. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:9782-9794. [PMID: 38597360 DOI: 10.1021/acs.jafc.3c09390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Uncontrolled inflammation contributes significantly to the mortality in acute respiratory infections. Our previous research has demonstrated that maize bran feruloylated oligosaccharides (FOs) possess notable anti-inflammatory properties linked to the NF-kB pathway regulation. In this study, we clarified that the oral administration of FOs moderately inhibited H1N1 virus infection and reduced lung inflammation in influenza-infected mice by decreasing a wide spectrum of cytokines (IFN-α, IFN-β, IL-6, IL-10, and IL-23) in the lungs. The mechanism involves FOs suppressing the transduction of the RIG-I/MAVS/TRAF3 signaling pathway, subsequently lowering the expression of NF-κB. In silico analysis suggests that FOs have a greater binding affinity for the RIG-I/MAVS signaling complex. This indicates that FOs have potential as promising targets for immune modulation. Moreover, in MAVS knockout mice, we confirmed that the anti-inflammatory function of FOs against influenza depends on MAVS. Comprehensive analysis using 16S rRNA gene sequencing and metabolite profiling techniques showed that FOs have the potential to restore immunity by modulating the gut microbiota. In conclusion, our study demonstrates that FOs are effective anti-inflammatory phytochemicals in inhibiting lung inflammation caused by influenza. This suggests that FOs could serve as a potential nutritional strategy for preventing the H1N1 virus infection and associated lung inflammation.
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Affiliation(s)
- Li Deng
- School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
| | - Shu-Lei Wei
- School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
| | - Lu Wang
- School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
| | - Jun-Qing Huang
- School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
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Ciutara CO, Iasella SV, Huang B, Barman S, Zasadzinski JA. Evolution of interfacial mechanics of lung surfactant mimics progression of acute respiratory distress syndrome. Proc Natl Acad Sci U S A 2023; 120:e2309900120. [PMID: 38085774 PMCID: PMC10743378 DOI: 10.1073/pnas.2309900120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 10/06/2023] [Indexed: 12/18/2023] Open
Abstract
How acute respiratory distress syndrome progresses from underlying disease or trauma is poorly understood, and there are no generally accepted treatments resulting in a 40% mortality rate. However, during the inflammation that accompanies this disease, the phospholipase A2 concentration increases in the alveolar fluids leading to the hydrolysis of bacterial, viral, and lung surfactant phospholipids into soluble lysolipids. We show that if the lysolipid concentration in the subphase reaches or exceeds its critical micelle concentration, the surface tension, γ, of dipalmitoyl phosphatidylcholine (DPPC) or Curosurf monolayers increases and the dilatational modulus, [Formula: see text], decreases to that of a pure lysolipid interface. This is consistent with DPPC being solubilized in lysolipid micelles and being replaced by lysolipid at the interface. These changes lead to [Formula: see text] which is the criterion for the Laplace instability that can lead to mechanical instabilities during lung inflation, potentially causing alveolar collapse. These findings provide a mechanism behind the alveolar collapse and uneven lung inflation during ARDS.
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Affiliation(s)
- Clara O. Ciutara
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN55455
| | - Steven V. Iasella
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN55455
| | - Boxun Huang
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN55455
| | - Sourav Barman
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN55455
| | - Joseph A. Zasadzinski
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN55455
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Li HY, Yang HG, Wu HM, Yao QQ, Zhang ZY, Meng QS, Fan LL, Wang JQ, Zheng N. Inhibitory effects of lactoferrin on pulmonary inflammatory processes induced by lipopolysaccharide by modulating the TLR4-related pathway. J Dairy Sci 2021; 104:7383-7392. [PMID: 33838887 DOI: 10.3168/jds.2020-19232] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 02/24/2021] [Indexed: 11/19/2022]
Abstract
This study tested the ability of lactoferrin to modulate pulmonary inflammation. To construct in vitro and in vivo inflammatory lung models, cells from the human lung adenocarcinoma cell line (A549) were exposed to lipopolysaccharide (LPS, 1 µg/mL), and mice (CD-1) were intratracheally administered LPS [10 mg/kg of body weight (BW), tracheal lumen injection], respectively. The A549 cells were preincubated with lactoferrin (10 mg/mL), and the mice were intraperitoneally injected with lactoferrin (100 mg/kg of BW), followed by LPS treatment. The concentrations of proinflammatory cytokines (IL-1β and TNF-α) in culture medium of A549 cells and in bronchoalveolar lavage fluid of the mice were determined using enzyme-linked immunosorbent assays. The toll-like receptor 4-related pathway (TLR4/MyD88/IRAK1/TRAF6/NFκB) was determined at gene and protein expression levels in A549 cells and mouse lung tissue. Results showed that LPS treatment significantly elevated the concentrations of IL-1β and TNF-α in the A549 cell culture medium and in bronchoalveolar lavage fluid of the mice; it also elevated both the mRNA and protein expressions of TLR4 and the TLR4 downstream factors in A549 cells and mouse lung tissue. Nevertheless, lactoferrin apparently depressed the releases of IL-1β and TNF-α from A549 cells and lung tissues stimulated by LPS, and significantly suppressed the TLR4 signaling pathway. Lactoferrin also promoted the enhancement of miR-146a expression in A549 cells and mouse lung tissue. Moreover, 100°C heating for 3 min caused total loss of the previously listed bioactivity of lactoferrin. Collectively, we proved that lactoferrin intervened in LPS-induced inflammation in the pulmonary cell model and in the mouse model, through inhibiting the TLR4-related pathway.
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Affiliation(s)
- H Y Li
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - H G Yang
- Sericultural and Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, P. R. China
| | - H M Wu
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - Q Q Yao
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - Z Y Zhang
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - Q S Meng
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - L L Fan
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - J Q Wang
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China.
| | - N Zheng
- Key Laboratory of Quality and Safety Control for Milk and Dairy Products, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China.
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Lungs from polytrauma donors with significant chest trauma can be safely used for transplantation. J Thorac Cardiovasc Surg 2020; 163:1719-1731.e2. [PMID: 33451825 DOI: 10.1016/j.jtcvs.2020.10.150] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 10/19/2020] [Accepted: 10/25/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND The use of organs from polytrauma donors for lung transplantation is controversial in the literature. For many centers, the radiologic manifestation of lung contusions is a clear reason to reject an organ offer. This results in the loss of potentially viable organs for the donor pool. METHODS We analyzed 1152 donor lungs procured by our transplant center between January 2010 and June 2018. These included 118 lungs with a history of polytrauma involving the chest. Sixteen polytrauma donor lungs were rejected after procurement. A total of 102 lungs were transplanted, divided into 2 groups: the polytrauma contusion group (n = 44), comprising polytrauma donors with radiologic signs of lung contusion at the time of offer, and the polytrauma clear group (n = 58), comprising polytrauma donors without lung contusion. Nontrauma donor lungs transplanted during the study period were assigned to a polytrauma control group (n = 650). Short- and long-term outcomes of the 3 groups were compared. RESULTS Basic demographic data and preoperative factors were similar in the 3 groups. Rates of primary graft dysfunction grade 3 at 72 hours did not differ among the 3 groups (0.0% vs 3.4% vs 3.9%; P = .409). The duration of ventilation was similar the 3 groups: 45 hours (interquartile range [IQR], 28-94 hours), 37 hours (IQR, 22-71 hours), and 42 hours (IQR, 22-96 hours), respectively (P = .674). Long-term graft survival was not impaired in the trauma groups compared with controls. One-year survival rates were 84.1% for the polytrauma contusion group, 93.1% for the polytrauma clear group, and 83.1% for the no polytrauma group. Five-year graft survival in the 3 groups was 74.7%, 87.2%, and 70.0%, respectively. CONCLUSIONS Lung transplantation using organs from polytrauma donors is associated with similar short- and long-term results as transplantation from nontrauma donors. The presence or absence of radiologic signs of lung contusion at the time of offer has no impact on primary graft function and long-term survival.
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Alekseeva AS, Boldyrev IA. Phospholipase A2. Methods for Activity Monitoring. BIOCHEMISTRY (MOSCOW), SUPPLEMENT SERIES A: MEMBRANE AND CELL BIOLOGY 2020. [DOI: 10.1134/s1990747820040030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Barman S, Davidson ML, Walker LM, Anna SL, Zasadzinski JA. Inflammation product effects on dilatational mechanics can trigger the Laplace instability and acute respiratory distress syndrome. SOFT MATTER 2020; 16:6890-6901. [PMID: 32643749 PMCID: PMC7462632 DOI: 10.1039/d0sm00415d] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In the lungs, the Laplace pressure, ΔP = 2γ/R, would be higher in smaller alveoli than larger alveoli unless the surface tension, γ decreases with alveolar interfacial area, A, such that 2ε > γ in which ε = A(dγ/dA) is the dilatational modulus. In Acute Respiratory Distress Syndrome (ARDS), lipase activity due to the immune response to an underlying trauma or disease causes single chain lysolipid concentrations to increase in the alveolar fluids via hydrolysis of double-chain phospholpids in bacterial, viral, and normal cell membranes. Increasing lysolipid concentrations decrease the dilatational modulus dramatically at breathing frequencies if the soluble lysolipid has sufficient time to diffuse off the interface, causing 2ε < γ, thereby potentially inducing the "Laplace Instability", in which larger alveoli have a lower internal pressure than smaller alveoli. This can lead to uneven lung inflation, alveolar flooding, and poor gas exchange, typical symptoms of ARDS. While the ARDS lung contains a number of lipid and protein species in the alveolar fluid in addition to lysolipids, the surface activity and frequency dependent dilatational modulus of lysolipid suggest how inflammation may lead to the lung instabilities associated with ARDS. At high frequencies, even at high lysolipid concentrations, 2ε - γ > 0, which may explain the benefits ARDS patients receive from high frequency oscillatory ventilation.
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Affiliation(s)
- Sourav Barman
- Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota, USA
| | - Michael L Davidson
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Lynn M Walker
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Shelly L Anna
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Joseph A Zasadzinski
- Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota, USA
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Keskin Y, Bedel C, Gökben Beceren N. Investigation of histopathological and radiological effects of surfactant treatment in an experimental female rat model of lung contusion. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2020; 22:1153-1157. [PMID: 31998456 PMCID: PMC6885389 DOI: 10.22038/ijbms.2019.32357.8258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Objective(s): Pulmonary contusion (PC) is a clinical entity that often accompanies blunt traumas. We aimed to investigate the radiological and histopathological effects of surfactant treatment in an experimental rat model in which lung contusion was formed by blunt thoracic trauma. Materials and Methods: 50 female Sprague-Dawley rats were used. Five groups were formed randomly. In groups 2, 4, and 5 lung contusion was made by the drop-weight method after anesthesia. Intratracheal surfactant was administered in the 4th hr in groups 3 and 4 and in the 24th hr in groups 4 and 5. All rats were sacrificed and their lungs removed at 48 hr after contusion. Alveolar edema, congestion, hemorrhage, destruction, leukocyte infiltration, immune staining were examined histopathologically. Results: When the first thoracic CT scans were evaluated, we observed two rats with rib fractures and four rats with pneumothorax. 4 and 48 hr thoracic CT evaluation contusion and atelectasis showed no statistically significant decrease (P>0.05). After sacrifice of group 2, in macroscopic evaluation, there was a heterogeneous contusion and hemorrhagic appearance in the lungs of rats and less hemorrhagic appearance was observed in Groups 4 and 5 than in Group 2. In comparison of Immunohistopathological findings, surfactant treatment showed a statistically significant decrease in leukocyte infiltration scores (P=0.046). Immunohistopathologically, surfactant group had more staining but only statistically significant when compared to groups 4 and sham. (P=0.036). Conclusion: Surfactant treatment may be of significant benefit in lung contusion secondary to blunt chest trauma, and further prospective evidence of its efficacy in such disorders is needed.
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Affiliation(s)
- Yasin Keskin
- Beyhekim State Hospital, Department of Emergency Medicine, Konya, Turkey
| | - Cihan Bedel
- Health Science University Antalya Training and Research Hospital, Department of Emergency Medicine, Antalya, Turkey
| | - Nesrin Gökben Beceren
- Süleyman Demirel University Faculty of Medicine, Department of Emergency Medicine, Isparta, Turkey
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Molecular Characterization of Hypoxic Alveolar Epithelial Cells After Lung Contusion Indicates an Important Role for HIF-1α. Ann Surg 2019; 267:382-391. [PMID: 27811509 DOI: 10.1097/sla.0000000000002070] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To understand the fate and regulation of hypoxic type II alveolar epithelial cells (AECs) after lung contusion (LC). BACKGROUND LC due to thoracic trauma is a major risk factor for the development of acute respiratory distress syndrome. AECs have recently been implicated as a primary driver of inflammation in LC. The main pathological consequence of LC is hypoxia, and a key mediator of adaptation to hypoxia is hypoxia-inducible factor (HIF)-1. We have recently published that HIF-1α is a major driver of acute inflammation after LC through type II AEC. METHODS LC was induced in wild-type mice (C57BL/6), luciferase-based hypoxia reporter mice (ODD-Luc), and HIF-1α conditional knockout mice. The degree of hypoxia was assessed using hypoxyprobe and in vivo imaging system. The fate of hypoxic AEC was evaluated by luciferase dual staining with caspases-3 and Ki-67, terminal deoxynucleotidyl transferase dUTP nick end labeling, and flow cytometry with ApoStat. NLRP-3 expression was determined by western blot. Laser capture microdissection was used to isolate AECs in vivo, and collected RNA was analyzed by Q-PCR for HIF-related pathways. RESULTS Global hypoxia was present after LC, but hypoxic foci were not uniform. Hypoxic AECs preferentially undergo apoptosis. There were significant reductions in NLRP-3 in HIF-1α conditional knockout mice. The expression of proteins involved in HIF-related pathways and inflammasome activation were significantly increased in hypoxic AECs. CONCLUSIONS These are the first in vivo data to identify, isolate, and characterize hypoxic AECs. HIF-1α regulation through hypoxic AECs is critical to the initiation of acute inflammation after LC.
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Nolin JD, Murphy RC, Gelb MH, Altemeier WA, Henderson WR, Hallstrand TS. Function of secreted phospholipase A 2 group-X in asthma and allergic disease. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:827-837. [PMID: 30529275 DOI: 10.1016/j.bbalip.2018.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 12/11/2022]
Abstract
Elevated secreted phospholipase A2 (sPLA2) activity in the airways has been implicated in the pathogenesis of asthma and allergic disease for some time. The identity and function of these enzymes in asthma is becoming clear from work in our lab and others. We focused on sPLA2 group X (sPLA2-X) after identifying increased levels of this enzyme in asthma, and that it is responsible for a large portion of sPLA2 activity in the airways and that the levels are strongly associated with features of airway hyperresponsiveness (AHR). In this review, we discuss studies that implicated sPLA2-X in human asthma, and murine models that demonstrate a critical role of this enzyme as a regulator of type-2 inflammation, AHR and production of eicosanoids. We discuss the mechanism by which sPLA2-X acts to regulate eicosanoids in leukocytes, as well as effects that are mediated through the generation of lysophospholipids and through receptor-mediated functions. This article is part of a Special Issue entitled Novel functions of phospholipase A2 Guest Editors: Makoto Murakami and Gerard Lambeau.
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Affiliation(s)
- James D Nolin
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - Ryan C Murphy
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - Michael H Gelb
- Department of Chemistry, University of Washington, Seattle, WA, United States of America; Department of Biochemistry, University of Washington, Seattle, WA, United States of America
| | - William A Altemeier
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - William R Henderson
- Division of Allergy and Infectious DIseases, University of Washington, Seattle, WA, United States of America
| | - Teal S Hallstrand
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America.
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12
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Kim HC, Suresh MV, Singh VV, Arick DQ, Machado-Aranda DA, Raghavendran K, Won YY. Polymer Lung Surfactants. ACS APPLIED BIO MATERIALS 2018; 1:581-592. [PMID: 30627707 PMCID: PMC6322699 DOI: 10.1021/acsabm.8b00061] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Animal-derived lung surfactants annually save 40 000 infants with neonatal respiratory distress syndrome (NRDS) in the United States. Lung surfactants have further potential for treating about 190 000 adult patients with acute respiratory distress syndrome (ARDS) each year. To this end, the properties of current therapeutics need to be modified. Although the limitations of current therapeutics have been recognized since the 1990s, there has been little improvement. To address this gap, our laboratory has been exploring a radically different approach in which, instead of lipids, proteins, or peptides, synthetic polymers are used as the active ingredient. This endeavor has led to an identification of a promising polymer-based lung surfactant candidate, poly(styrene-b-ethylene glycol) (PS-PEG) polymer nanomicelles. PS-PEG micelles produce extremely low surface tension under high compression because PS-PEG micelles have a strong affinity to the air-water interface. NMR measurements support that PS-PEG micelles are less hydrated than ordinary polymer micelles. Studies using mouse models of acid aspiration confirm that PS-PEG lung surfactant is safe and efficacious.
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Affiliation(s)
- Hyun Chang Kim
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | | | - Vikas V. Singh
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Davis Q. Arick
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | | | - Krishnan Raghavendran
- Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - You-Yeon Won
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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Dolgachev V, Panicker S, Balijepalli S, McCandless LK, Yin Y, Swamy S, Suresh MV, Delano MJ, Hemmila MR, Raghavendran K, Machado-Aranda D. Electroporation-mediated delivery of FER gene enhances innate immune response and improves survival in a murine model of pneumonia. Gene Ther 2018; 25:359-375. [PMID: 29907877 PMCID: PMC6195832 DOI: 10.1038/s41434-018-0022-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 05/02/2018] [Accepted: 05/11/2018] [Indexed: 12/23/2022]
Abstract
Previously, we reported that electroporation-mediated (EP) delivery of the FER gene improved survival in a combined trauma-pneumonia model. The mechanism of this protective effect is unknown. In this paper, we performed a pneumonia model in C57/BL6 mice with 500 CFU of Klebsiella pneumoniae. After inoculation, a plasmid encoding human FER was delivered by EP into the lung (PNA/pFER-EP). Survival of FER-treated vs. controls (PNA; PNA/EP-pcDNA) was recorded. In parallel cohorts, bronchial alveolar lavage (BAL) and lung were harvested at 24 and 72 h with markers of infection measured. FER-EP-treated animals reduced bacterial counts and had better 5-day survival compared to controls (80 vs. 20 vs. 25%; p < 0.05). Pre-treatment resulted in 100% survival. With FER, inflammatory monocytes were quickly recruited into BAL. These cells had increased surface expression for Toll-receptor 2 and 4, and increased phagocytic and myeloperoxidase activity at 24 h. Samples from FER electroporated animals had increased phosphorylation of STAT transcription factors, varied gene expression of IL1β, TNFα, Nrf2, Nlrp3, Cxcl2, HSP90 and increased cytokine production of TNF-α, CCL-2, KC, IFN-γ, and IL-1RA. In a follow-up experiment, using Methicillin-resistant Staphylococcus aureus (MRSA) similar bacterial reduction effects were obtained with FER gene delivery. We conclude that FER overexpression improves survival through STAT activation enhancing innate immunity and accelerating bacterial clearance in the lung. This constitutes a novel mechanism of inflammatory regulation with therapeutic potential in the setting of hospital-acquired pneumonia.
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Affiliation(s)
- Vladislav Dolgachev
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Sreehari Panicker
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Sanjay Balijepalli
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Lane Kelly McCandless
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Yue Yin
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Samantha Swamy
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - M V Suresh
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Matthew J Delano
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Mark R Hemmila
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - Krishnan Raghavendran
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA
| | - David Machado-Aranda
- Division of Acute Care Surgery, University of Michigan, 1500 E Medical Center Dr, UH-1C421, SPC 5033, Ann Arbor, MI, 48109-5033, USA.
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Machado-Aranda D. [The Use Of Pulmonary Gene Therapy In The Treatment Of Experimental Models Of Pneumonia And Septicemia]. GACETA MEDICA DE CARACAS 2018; 126:5-14. [PMID: 30100668 PMCID: PMC6086359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- David Machado-Aranda
- Laboratorio del Estudio de la Biología y Terapia Molecular para el Manejo del Trauma Pulmonar
- División de Cirugía de Trauma, Quemados y Urgencias - Terapia Intensiva Quirúrgica, Universidad de Michigan, Ann Arbor, Michigan, Estados Unidos de América
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Omar NM, Sarhan NR. The possible protective role of pumpkin seed oil in an animal model of acid aspiration pneumonia: Light and electron microscopic study. Acta Histochem 2017; 119:161-171. [PMID: 28122663 DOI: 10.1016/j.acthis.2017.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 01/02/2017] [Indexed: 12/24/2022]
Abstract
Aspiration pneumonitis is a common problem occurring in many clinical disorders. Pumpkin seed oil (PO) is a rich source of antioxidants. This work aimed to assess the effect of PO on the lung histopathological changes induced by acid aspiration. Forty male albino rats assigned to four groups were used. Rats of control group were instilled intratracheally with normal saline 2mL/kg. HCL group instilled with 2mL/kg of HCL 0.1N, pH 1.25. PO group received pumpkin seed oil (PO) orally (∼1375mg/kgbw/day) for 7days. HCL+PO group instilled with 2mL/kg of HCL 0.1N, pH 1.25 and received PO at the same dose of PO group. Lung tissue samples were processed for light, electron microscopic and immunohistochemical study using anti inducible NO synthase (iNOS). The lung of HCL group demonstrated thickened interalveolar septa, inflammatory cell infiltration and significant increase in the area percent of collagenous fibers and immune expression of iNOS. Ultra structurally, disrupted alveolocapillay membrane, degenerated type II pneumocytes and plentiful alveolar macrophages were evident. PO administration partially attenuated these histological and ultra structural alterations and reduced iNOS immune-expression in lung tissue. In conclusion, PO has a protective effect against HCL aspiration lung injury most probably through its antioxidant activity.
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Notter RH, Gupta R, Schwan AL, Wang Z, Shkoor MG, Walther FJ. Synthetic lung surfactants containing SP-B and SP-C peptides plus novel phospholipase-resistant lipids or glycerophospholipids. PeerJ 2016; 4:e2635. [PMID: 27812430 PMCID: PMC5088750 DOI: 10.7717/peerj.2635] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 09/30/2016] [Indexed: 01/22/2023] Open
Abstract
Background This study examines the biophysical and preclinical pulmonary activity of synthetic lung surfactants containing novel phospholipase-resistant phosphonolipids or synthetic glycerophospholipids combined with Super Mini-B (S-MB) DATK and/or SP-Css ion-lock 1 peptides that replicate the functional biophysics of surfactant proteins (SP)-B and SP-C. Phospholipase-resistant phosphonolipids used in synthetic surfactants are DEPN-8 and PG-1, molecular analogs of dipalmitoyl phosphatidylcholine (DPPC) and palmitoyl-oleoyl phosphatidylglycerol (POPG), while glycerophospholipids used are active lipid components of native surfactant (DPPC:POPC:POPG 5:3:2 by weight). The objective of the work is to test whether these novel lipid/peptide synthetic surfactants have favorable preclinical activity (biophysical, pulmonary) for therapeutic use in reversing surfactant deficiency or dysfunction in lung disease or injury. Methods Surface activity of synthetic lipid/peptide surfactants was assessed in vitro at 37 °C by measuring adsorption in a stirred subphase apparatus and dynamic surface tension lowering in pulsating and captive bubble surfactometers. Shear viscosity was measured as a function of shear rate on a Wells-Brookfield micro-viscometer. In vivo pulmonary activity was determined by measuring lung function (arterial oxygenation, dynamic lung compliance) in ventilated rats and rabbits with surfactant deficiency/dysfunction induced by saline lavage to lower arterial PO2 to <100 mmHg, consistent with clinical acute respiratory distress syndrome (ARDS). Results Synthetic surfactants containing 5:3:2 DPPC:POPC:POPG or 9:1 DEPN-8:PG-1 combined with 3% (by wt) of S-MB DATK, 3% SP-Css ion-lock 1, or 1.5% each of both peptides all adsorbed rapidly to low equilibrium surface tensions and also reduced surface tension to ≤1 mN/m under dynamic compression at 37 °C. However, dual-peptide surfactants containing 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 combined with 9:1 DEPN-8:PG-1 or 5:3:2 DPPC:POPC:POPG had the greatest in vivo activity in improving arterial oxygenation and dynamic lung compliance in ventilated animals with ARDS. Saline dispersions of these dual-peptide synthetic surfactants were also found to have shear viscosities comparable to or below those of current animal-derived surfactant drugs, supporting their potential ease of deliverability by instillation in future clinical applications. Discussion Our findings support the potential of dual-peptide synthetic lipid/peptide surfactants containing S-MB DATK + SP-Css ion-lock 1 for treating diseases of surfactant deficiency or dysfunction. Moreover, phospholipase-resistant dual-peptide surfactants containing DEPN-8/PG-1 may have particular applications in treating direct forms of ARDS where endogenous phospholipases are present in the lungs.
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Affiliation(s)
- Robert H Notter
- Department of Pediatrics, University of Rochester , Rochester , NY , United States
| | - Rohun Gupta
- Department of Pediatrics, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center , Torrance , CA , United States
| | - Adrian L Schwan
- Department of Chemistry, University of Guelph , Guelph , Ontario , Canada
| | - Zhengdong Wang
- Department of Pediatrics, University of Rochester , Rochester , NY , United States
| | - Mohanad Gh Shkoor
- Department of Chemistry, University of Guelph , Guelph , Ontario , Canada
| | - Frans J Walther
- Department of Pediatrics, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, United States; Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
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Electroporation-mediated delivery of the FER gene in the resolution of trauma-related fatal pneumonia. Gene Ther 2016; 23:785-796. [PMID: 27454317 PMCID: PMC5096957 DOI: 10.1038/gt.2016.58] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/19/2016] [Accepted: 07/11/2016] [Indexed: 12/18/2022]
Abstract
Injured patients with lung contusion (LC) are at risk of developing bacterial pneumonia (PNA) followed by sepsis and death. A recent genome-wide association study (GWAS) showed FER gene expression positively correlating with survival rates among individuals with above conditions. We sought to determine whether electroporation (EP)-mediated delivery of FER gene could indeed improve survival, in a lethal model of combined LC and PNA. C57BL/6 mice sustained unilateral LC, which preceded a 500 Klebsiella colony forming unit (CFU) inoculation by 6 h. In-between these insults, human FER plasmid (pFER) was introduced into the lungs followed by eight EP pulses applied externally (10 ms at 200 V cm-1). Control groups included EP of empty vector (pcDNA3) or Na+/K+-ATPase genes (pPump) and no treatment (LC+PNA). We recorded survival, histology, lung mechanics, bronchial alveolar lavage (BAL) fluid, FER and inflammatory gene expression and bacteriology. The data show that 7-day survival was significantly improved by pFER compared with control groups. pFER increased BAL monocytes and activated antibacterial response genes (nitric oxide synthase (NOS), Fizz). pFER treatment showed decreased lung and blood Klebsiella counts reaching, in some cases, complete sterilization. In conclusion, FER gene delivery promoted survival in LC+PNA mice via recruitment of activated immune cells, improving efficiency of bacterial clearance within contused lung.
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18
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Potential Metabolic Biomarkers to Identify Interstitial Lung Abnormalities. Int J Mol Sci 2016; 17:ijms17071148. [PMID: 27438829 PMCID: PMC4964521 DOI: 10.3390/ijms17071148] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 05/25/2016] [Accepted: 06/15/2016] [Indexed: 02/07/2023] Open
Abstract
Determining sensitive biomarkers in the peripheral blood to identify interstitial lung abnormalities (ILAs) is essential for the simple early diagnosis of ILAs. This study aimed to determine serum metabolic biomarkers of ILAs and the corresponding pathogenesis. Three groups of subjects undergoing health screening, including healthy subjects, subjects with ILAs, and subjects who were healthy initially and with ILAs one year later (Healthy→ILAs), were recruited for this study. The metabolic profiles of all of the subjects’ serum were analyzed by liquid chromatography quadruple time-of-flight mass spectrometry. The metabolic characteristics of the ILAs subjects were discovered, and the corresponding biomarkers were predicted. The metabolomic data from the Healthy→ILAs subjects were collected for further verification. The results indicated that five serum metabolite alterations (up-regulated phosphatidylcholine, phosphatidic acid, betaine aldehyde and phosphatidylethanolamine, as well as down-regulated 1-acylglycerophosphocholine) were sensitive and reliable biomarkers for identifying ILAs. Perturbation of the corresponding biological pathways (RhoA signaling, mTOR/P70S6K signaling and phospholipase C signaling) might be at least partially responsible for the pathogenesis of ILAs. This study may provide a good template for determining the early diagnostic markers of subclinical disease status and for obtaining a better understanding of their pathogenesis.
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Metabolomics Investigation Reveals Metabolite Mediators Associated with Acute Lung Injury and Repair in a Murine Model of Influenza Pneumonia. Sci Rep 2016; 6:26076. [PMID: 27188343 PMCID: PMC4870563 DOI: 10.1038/srep26076] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 04/25/2016] [Indexed: 11/23/2022] Open
Abstract
Influenza virus infection (IVI) can cause primary viral pneumonia, which may progress to acute lung injury (ALI) and respiratory failure with a potentially fatal outcome. At present, the interactions between host and influenza virus at molecular levels and the underlying mechanisms that give rise to IVI-induced ALI are poorly understood. We conducted a comprehensive mass spectrometry-based metabolic profiling of serum, lung tissue and bronchoalveolar lavage fluid (BALF) from a non-lethal mouse model with influenza A virus at 0, 6, 10, 14, 21 and 28 days post infection (dpi), representing the major stages of IVI. Distinct metabolite signatures were observed in mice sera, lung tissues and BALF, indicating the molecular differences between systematic and localized host responses to IVI. More than 100 differential metabolites were captured in mice sera, lung tissues and BALF, including purines, pyrimidines, acylcarnitines, fatty acids, amino acids, glucocorticoids, sphingolipids, phospholipids, etc. Many of these metabolites belonged to pulmonary surfactants, indicating IVI-induced aberrations of the pulmonary surfactant system might play an important role in the etiology of respiratory failure and repair. Our findings revealed dynamic host responses to IVI and various metabolic pathways linked to disease progression, and provided mechanistic insights into IVI-induced ALI and repair process.
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20
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Priolo C, Ricoult SJH, Khabibullin D, Filippakis H, Yu J, Manning BD, Clish C, Henske EP. Tuberous sclerosis complex 2 loss increases lysophosphatidylcholine synthesis in lymphangioleiomyomatosis. Am J Respir Cell Mol Biol 2015; 53:33-41. [PMID: 25780943 DOI: 10.1165/rcmb.2014-0379rc] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Lymphangioleiomyomatosis (LAM) is a destructive lung disease affecting women. LAM is caused by mutations in the tuberous sclerosis complex (TSC) genes. The TSC protein complex inhibits the mechanistic/mammalian target of rapamycin complex 1 (mTORC1), which is a master regulator of cellular metabolism. Using mass spectrometry-based lipid profiling, we analyzed plasma from patients with LAM and discovered elevated levels of four lysophosphatidylcholine (LPC) species (C16:0, C18:0, C18:1, and C20:4) compared with those in healthy control women. To investigate whether these lipids are generated in a TSC2-dependent manner, we profiled in vitro preclinical models of TSC/LAM and found significant LPC accumulation in TSC2-deficient cells relative to TSC2-expressing control cells. These lysoglycerophospholipid changes occurred alongside changes in other phospholipid and neutral lipid species. Treatment with rapamycin or torin1 or down-regulation of sterol regulatory element-binding protein (SREBP), a lipogenic transcription factor, did not suppress LPC in TSC2-deficient cells. Inhibition of distinct isoforms of phospholipase A2 decreased the proliferation of TSC2-deficient cells. Collectively, these results demonstrate that TSC2-deficient cells have enhanced choline phospholipid metabolism and reveal a novel function of the TSC proteins in choline lysoglycerophospholipid metabolism, with implications for disease pathogenesis and targeted therapeutic strategies.
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Affiliation(s)
- Carmen Priolo
- 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Stéphane J H Ricoult
- 2 Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; and
| | - Damir Khabibullin
- 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Harilaos Filippakis
- 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Jane Yu
- 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Brendan D Manning
- 2 Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; and
| | - Clary Clish
- 3 Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Elizabeth P Henske
- 1 Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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Suresh MV, Ramakrishnan SK, Thomas B, Machado-Aranda D, Bi Y, Talarico N, Anderson E, Yatrik SM, Raghavendran K. Activation of hypoxia-inducible factor-1α in type 2 alveolar epithelial cell is a major driver of acute inflammation following lung contusion. Crit Care Med 2014; 42:e642-53. [PMID: 25014067 DOI: 10.1097/ccm.0000000000000488] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Lung contusion is a major risk factor for the development of acute respiratory distress syndrome. Hypoxia-inducible factor-1α is the primary transcription factor that is responsible for regulating the cellular response to changes in oxygen tension. We set to determine if hypoxia-inducible factor-1α plays a role in the pathogenesis of acute inflammatory response and injury in lung contusion. DESIGN Nonlethal closed-chest unilateral lung contusion was induced in a hypoxia reporter mouse model and type 2 cell-specific hypoxia-inducible factor-1α conditional knockout mice. The mice were killed at 5-, 24-, 48-, and 72-hour time points, and the extent of systemic and tissue hypoxia was assessed. In addition, injury and inflammation were assessed by measuring bronchoalveolar lavage cells (flow cytometry and cytospin), albumin (permeability injury), and cytokines (inflammation). Isolated type 2 cells from the hypoxia-inducible factor-1α conditional knockout mice were isolated and evaluated for proinflammatory cytokines following lung contusion. Finally, the role of nuclear factor-κB and interleukin-1β as intermediates in this interaction was studied. RESULTS Lung contusion induced profound global hypoxia rapidly. Increased expression of hypoxia-inducible factor-1α from lung samples was observed as early as 60 minutes, following the insult. The extent of lung injury following lung contusion was significantly reduced in conditional knockout mice at all the time points, when compared with the wild-type littermate mice. Release of proinflammatory cytokines, such as interleukin-1β, interleukin-6, macrophage inflammatory protein-2, and keratinocyte chemoattractant, was significantly lower in conditional knockout mice. These actions are in part mediated through nuclear factor-κB. Hypoxia-inducible factor-1α in lung epithelial cells was shown to regulate interleukin-1β promoter activity. CONCLUSION Activation of hypoxia-inducible factor-1α in type 2 cell is a major driver of acute inflammation following lung contusion.
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Affiliation(s)
- Madathilparambil V Suresh
- 1Department of Surgery, University of Michigan Medical School, Ann Arbor, MI. 2Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI. 3Department of Internal Medicine, Division of Gastroenterology, University of Michigan Medical School, Ann Arbor, MI
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Alveolar macrophage depletion increases the severity of acute inflammation following nonlethal unilateral lung contusion in mice. J Trauma Acute Care Surg 2014; 76:982-90. [PMID: 24662861 DOI: 10.1097/ta.0000000000000163] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Lung contusion (LC) is a common injury resulting from blunt thoracic trauma. LC is an important risk factor for the development acute lung injury, adult respiratory distress syndrome, and ventilator-associated pneumonia, all of which increase mortality from trauma. LC produces a nonspecific immune cellular response. Neutrophil recruitment is known to increase the severity of inflammation during LC. However, the exact role of macrophages in modulating the response to LC has not been well described. METHODS We used a cortical contusion impactor to induce unilateral LC in mice. Thoracic micro computed tomographic scans of these animals were obtained to document radiologic changes over time following LC. To understand the role of macrophages during LC, liposomal clodronate was used to deplete macrophage levels before traumatic insult. Acute inflammatory attributes after LC were assessed, by measuring pressure-volume mechanics; quantifying bronchial alveolar lavage levels of leukocytes, albumin, and cytokines; and finally examining lung specimen histopathology at 5, 24, 48, and 72 hours after injury. RESULTS After LC, alveolar macrophage numbers were significantly reduced and exhibited slowed recovery. Simultaneously, there was a significant increase in bronchial alveolar lavage neutrophil counts. The loss of macrophages could be attributed to both cellular apoptosis and necrosis. Pretreatment with clodronate increased the severity of lung inflammation as measured by worsened pulmonary compliance, increased lung permeability, amplification of neutrophil recruitment, and increases in early proinflammatory cytokine levels. CONCLUSION The presence of regulatory alveolar macrophages plays an important role in the pathogenesis of acute inflammation following LC.
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Topcu-Tarladacalisir Y, Tarladacalisir T, Sapmaz-Metin M, Karamustafaoglu A, Uz YH, Akpolat M, Cerkezkayabekir A, Turan FN. N-Acetylcysteine counteracts oxidative stress and protects alveolar epithelial cells from lung contusion-induced apoptosis in rats with blunt chest trauma. J Mol Histol 2014; 45:463-71. [PMID: 24442604 DOI: 10.1007/s10735-014-9563-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 01/09/2014] [Indexed: 01/11/2023]
Abstract
The aim of this study was to investigate the protective effects of N-acetylcysteine (NAC) on peroxidative and apoptotic changes in the contused lungs of rats following blunt chest trauma. The rats were randomly divided into three groups: control, contusion, and contusion + NAC. All the rats, apart from those in the control group, performed moderate lung contusion. A daily intramuscular NAC injection (150 mg/kg) was given immediately following the blunt chest trauma and was continued for two additional days following cessation of the trauma. Samples of lung tissue were taken in order to evaluate the tissue malondialdehyde (MDA) level, histopathology, and epithelial cell apoptosis using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and active caspase-3 immunostaining. In addition, we immunohistochemically evaluated the expression of surfactant protein D (SP-D) in the lung tissue. The blunt chest trauma-induced lung contusion resulted in severe histopathological injury, as well as an increase in the MDA level and in the number of cells identified on TUNEL assay together with active caspase-3 positive epithelial cells, but a decrease in the number of SP-D positive alveolar type 2 (AT-2) cells. NAC treatment effectively attenuated histopathologic, peroxidative, and apoptotic changes, as well as reducing alterations in SP-D expression in the lung tissue. These findings indicate that the beneficial effects of NAC administrated following blunt chest trauma is related to the regulation of oxidative stress and apoptosis.
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