scholarly journals The Elk1/MMP-9 axis regulates E-cadherin and occludin in ventilator-induced lung injury

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhao Tao ◽  
Yan Jie ◽  
Zhang Mingru ◽  
Gu Changping ◽  
Yang Fan ◽  
...  
Keyword(s):  
Lung Injury ◽  
Tidal Volume ◽  
Tight Junctions ◽  
Cyclic Stretch ◽  
High Tidal Volume ◽  
Ventilator Induced Lung Injury ◽  
Cell Counts ◽  
E Cadherin

Abstract Background Ventilator-induced lung injury (VILI) is a common complication in the treatment of respiratory diseases with high morbidity and mortality. ETS-domain containing protein (Elk1) and Matrix metalloproteinase (MMP) 9 are involved in VILI, but the roles have not been fully elucidated. This study examined the mechanisms of the activation of MMP-9 and Elk1 regulating barrier function in VILI in vitro and in vivo. Methods For the in vitro study, Mouse lung epithelial cells (MLE-12) were pre-treated with Elk1 siRNA or MMP-9 siRNA for 48 h prior to cyclic stretch at 20% for 4 h. For the in vivo study, C57BL/6 mice were pre-treated with Elk1 siRNA or MMP-9 siRNA for 72 h prior to 4 h of mechanical ventilation. The expressions of Elk1, MMP-9, Tissue inhibitor of metalloproteinase 1 (TIMP-1), E-cadherin, and occludin were measured by Western blotting. The intracellular distribution of E-cadherin and occludin was shown by immunofluorescence. The degree of pulmonary edema and lung injury were evaluated by Hematoxylin–eosin (HE) staining, lung injury scores, Wet/Dry (W/D) weight ratio, total cell counts, and Evans blue dye. Results 20% cyclic stretch and high tidal volume increases the expressions of Elk1, MMP-9, and TIMP-1, increases the ratio of MMP-9/TIMP-1, decreases the E-cadherin and occludin level. Elk1 siRNA or MMP-9 siRNA reverses the degradations of E-cadherin, occludin, and the ratio of MMP-9/TIMP-1 caused by cyclic stretch. Elk1 siRNA decreases the MMP-9 level with or not 20% cyclic stretch and high tidal volume. Conclusions The results demonstrate mechanical stretch damages the tight junctions and aggravates the permeability in VILI, Elk1 plays an important role in affecting the tight junctions and permeability by regulating the balance of MMP-9 and TIMP-1, thus indicating the therapeutic potential of Elk1 to treat VILI.

scholarly journals Mechanical Ventilation Induces Desensitization of Lung Axl Tyrosine Kinase Receptors

2018 ◽  
Vol 129 (1) ◽  
pp. 143-153 ◽  
Author(s):  
Gail Otulakowski ◽  
Doreen Engelberts ◽  
Martin Post ◽  
Claire Masterson ◽  
Brian P. Kavanagh
Keyword(s):  
Lung Injury ◽  
Tidal Volume ◽  
Calcium Ionophore ◽  
Cyclic Stretch ◽  
High Tidal Volume ◽  
Cytokine Signaling ◽  
Lung Physiology ◽  
Lung Endothelial Cells

Abstract Background Lower tidal volumes are increasingly used in acute respiratory distress syndrome, but mortality has changed little in the last 20 yr. Therefore, in addition to ventilator settings, it is important to target molecular mediators of injury. Sepsis and other inflammatory states increase circulating concentrations of Gas6, a ligand for the antiinflammatory receptor Axl, and of a soluble decoy form of Axl. We investigated the effects of lung stretch on Axl signaling. Methods We used a mouse model of early injury from high tidal volume and assessed the effects of inhibiting Axl on in vivo lung injury (using an antagonist R428, n = 4/group). We further determined the effects of stretch on Axl activation using in vitro lung endothelial cells. Results High tidal volume caused mild injury (compliance decreased 6%) as intended, and shedding of the Axl receptor (soluble Axl in bronchoalveolar fluid increased 77%). The Axl antagonist R428 blocked the principal downstream Axl target (suppressor of cytokine signaling 3 [SOCS3]) but did not worsen lung physiology or inflammation. Cyclic stretch in vitro caused Axl to become insensitive to activation by its agonist, Gas6. Finally, in vitro Axl responses were rescued by blocking stretch-activated calcium channels (using guanidinium chloride [GdCl3]), and the calcium ionophore ionomycin replicated the effect of stretch. Conclusions These data suggest that lung endothelial cell overdistention activates ion channels, and the resultant influx of Ca2+ inactivates Axl. Downstream inactivation of Axl by stretch was not anticipated; preventing this would be required to exploit Axl receptors in reducing lung injury.

scholarly journals Mechanosensitive cation channel Piezo1 contributes to ventilator-induced lung injury by activating RhoA/ROCK1 in rats

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Yang Zhang ◽  
Lulu Jiang ◽  
Tianfeng Huang ◽  
Dahao Lu ◽  
Yue Song ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Lung Injury ◽  
Tidal Volume ◽  
Cyclic Stretch ◽  
High Tidal Volume ◽  
Enzyme Linked Immunosorbent Assay ◽  
Sprague Dawley ◽  
Ventilator Induced Lung Injury ◽  
Enhanced Expression ◽  
Underlying Mechanisms

Abstract Background Mechanical ventilation can induce or aggravate lung injury, which is termed ventilator-induced lung injury (VILI). Piezo1 is a key element of the mechanotransduction process and can transduce mechanical signals into biological signals by mediating Ca2+ influx, which in turn regulates cytoskeletal remodeling and stress alterations. We hypothesized that it plays an important role in the occurrence of VILI, and investigated the underlying mechanisms. Methods High tidal volume mechanical ventilation and high magnitude cyclic stretch were performed on Sprague–Dawley rats, and A549 and human pulmonary microvascular endothelial cells, respectively, to establish VILI models. Immunohistochemical staining, flow cytometry, histological examination, enzyme-linked immunosorbent assay, western blotting, quantitative real-time polymerase chain reaction and survival curves were used to assess the effect of Piezo1 on induction of lung injury, as well as the signaling pathways involved. Results We observed that Piezo1 expression increased in the lungs after high tidal volume mechanical ventilation and in cyclic stretch-treated cells. Mechanistically, we observed the enhanced expression of RhoA/ROCK1 in both cyclic stretch and Yoda1-treated cells, while the deficiency or inhibition of Piezo1 dramatically antagonized RhoA/ROCK1 expression. Furthermore, blockade of RhoA/ROCK1 signaling using an inhibitor did not affect Piezo1 expression. GSMTx4 was used to inhibit Piezo1, which alleviated VILI-induced pathologic changes, water content and protein leakage in the lungs, and the induction of systemic inflammatory mediators, and improved the 7-day mortality rate in the model rats. Conclusions These findings indicate that Piezo1 affects the development and progression of VILI through promotion of RhoA/ROCK1 signaling.

Mechanisms of early pulmonary neutrophil sequestration in ventilator-induced lung injury in mice

2004 ◽  
Vol 287 (5) ◽  
pp. L902-L910 ◽  
Author(s):  
Sharmila Choudhury ◽  
Michael R. Wilson ◽  
Michael E. Goddard ◽  
Kieran P. O'Dea ◽  
Masao Takata
Keyword(s):  
Lung Injury ◽  
Tidal Volume ◽  
Molecular Mechanisms ◽  
Control Ventilation ◽  
Volume Control ◽  
Neutrophil Sequestration ◽  
Ventilator Induced Lung Injury ◽  
Volume Control Ventilation

Polymorphonuclear leukocytes (PMN) play an important role in ventilator-induced lung injury (VILI), but the mechanisms of pulmonary PMN recruitment, particularly early intravascular PMN sequestration during VILI, have not been elucidated. We investigated the physiological and molecular mechanisms of pulmonary PMN sequestration in an in vivo mouse model of VILI. Anesthetized C57/BL6 mice were ventilated for 1 h with high tidal volume (injurious ventilation), low tidal volume and high positive end-expiratory pressure (protective ventilation), or normal tidal volume (control ventilation). Pulmonary PMN sequestration analyzed by flow cytometry of lung cell suspensions was substantially enhanced in injurious ventilation compared with protective and control ventilation, preceding development of physiological signs of lung injury. Anesthetized, spontaneously breathing mice with continuous positive airway pressure demonstrated that raised alveolar pressure alone does not induce PMN entrapment. In vitro leukocyte deformability assay indicated stiffening of circulating leukocytes in injurious ventilation compared with control ventilation. PMN sequestration in injurious ventilation was markedly inhibited by administration of anti-L-selectin antibody, but not by anti-CD18 antibody. These results suggest that mechanical ventilatory stress initiates pulmonary PMN sequestration early in the course of VILI, and this phenomenon is associated with stretch-induced inflammatory events leading to PMN stiffening and mediated by L-selectin-dependent but CD18-independent mechanisms.

scholarly journals Rap1 mediates protective effects of iloprost against ventilator-induced lung injury

2009 ◽  
Vol 107 (6) ◽  
pp. 1900-1910 ◽  
Author(s):  
Anna A. Birukova ◽  
Panfeng Fu ◽  
Junjie Xing ◽  
Konstantin G. Birukov
Keyword(s):  
Lung Injury ◽  
Bronchoalveolar Lavage ◽  
Tidal Volume ◽  
Evans Blue ◽  
High Tidal Volume ◽  
Protective Effects ◽  
Ventilator Induced Lung Injury ◽  
High Tidal Volume Ventilation ◽  
Volume Ventilation

Prostaglandin I2 (PGI2) has been shown to attenuate vascular constriction, hyperpermeability, inflammation, and acute lung injury. However, molecular mechanisms of PGI2 protective effects on pulmonary endothelial cells (EC) are not well understood. We tested a role of cAMP-activated Epac-Rap1 pathway in the barrier protective effects of PGI2 analog iloprost in the murine model of ventilator-induced lung injury. Mice were treated with iloprost (2 μg/kg) after onset of high tidal volume ventilation (30 ml/kg, 4 h). Bronchoalveolar lavage, histological analysis, and measurements of Evans blue accumulation were performed. In vitro, microvascular EC barrier function was assessed by morphological analysis of agonist-induced gap formation and monitoring of Rho pathway activation and EC permeability. Iloprost reduced bronchoalveolar lavage protein content, neutrophil accumulation, capillary filtration coefficient, and Evans blue albumin extravasation caused by high tidal volume ventilation. Small-interfering RNA-based Rap1 knockdown inhibited protective effects of iloprost. In vitro, iloprost increased barrier properties of lung microvascular endothelium and alleviated thrombin-induced EC barrier disruption. In line with in vivo results, Rap1 depletion attenuated protective effects of iloprost in the thrombin model of EC permeability. These data describe for the first time protective effects for Rap1-dependent signaling against ventilator-induced lung injury and pulmonary endothelial barrier dysfunction.

scholarly journals Mechanosensitive Cation Channel Piezo1 Contributes To Ventilator-Induced Lung Injury By Activating RhoA/ROCK1 In Rats

2021 ◽  
Author(s):  
Yang Zhang ◽  
Lulu Jiang ◽  
Tianfeng Huang ◽  
Dahao Lu ◽  
Yue Song ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Lung Injury ◽  
Tidal Volume ◽  
Cyclic Stretch ◽  
High Tidal Volume ◽  
Enzyme Linked Immunosorbent Assay ◽  
Sprague Dawley ◽  
Reverse Transcription Pcr ◽  
Ventilator Induced Lung Injury ◽  
Underlying Mechanisms

Abstract Background: Mechanical ventilation can induce or aggravate lung injury, which is termed ventilator‑induced lung injury. Piezo1 is a key element of the mechanotransduction process and can transduce mechanical signals into biological signals by mediating Ca2+ influx, which in turn regulates cytoskeletal remodeling and stress alterations. We hypothesized that it plays an important role in the occurrence of ventilator‑induced lung injury, and we investigated the underlying mechanisms. Methods: High tidal volume mechanical ventilation and high magnitude cyclic stretch were performed on Sprague Dawley rats, and A549 and human pulmonary microvascular endothelial cells, respectively, to establish ventilator‑induced lung injury models. Immunohistochemical staining, flow cytometry, histological examination, enzyme-linked immunosorbent assay, western blotting, quantitative real-time reverse transcription-PCR and survival curves were used to assess the effect of Piezo1 on induction of lung injury, as well as the signaling pathways involved.Results: We observed that Piezo1 expression increased in the lungs after high tidal volume mechanical ventilation and in cyclic stretch-treated cells. Mechanistically, we observed the enhanced expression of RhoA/ROCK1 in both cyclic stretch and Yoda1-treated cells, while the deficiency or inhibition of Piezo1 dramatically antagonized RhoA/ROCK1 expression. Furthermore, blockade of RhoA/ROCK1 signaling using an inhibitor did not affect Piezo1 expression. GSMTx4 was used to inhibit Piezo1, which alleviated ventilator‑induced lung injury-induced pathologic changes, water content and protein leakage in the lungs, and the induction of systemic inflammatory mediators, and improved the 7-day mortality rate in the model rats. Conclusions: These findings indicate that Piezo1 affects the development and progression of ventilator‑induced lung injury through promotion of RhoA/ROCK1 signaling.

scholarly journals High tidal volume upregulates intrapulmonary cytokines in an in vivo mouse model of ventilator-induced lung injury

2003 ◽  
Vol 95 (4) ◽  
pp. 1385-1393 ◽  
Author(s):  
Michael R. Wilson ◽  
Sharmila Choudhury ◽  
Michael E. Goddard ◽  
Kieran P. O'Dea ◽  
Andrew G. Nicholson ◽  
...  
Keyword(s):  
Lung Injury ◽  
Mouse Model ◽  
Tidal Volume ◽  
Lavage Fluid ◽  
Lung Lavage ◽  
High Tidal Volume ◽  
Lung Pathology ◽  
Ventilator Induced Lung Injury ◽  
Tnf Α

Mechanical ventilation has been demonstrated to exacerbate lung injury, and a sufficiently high tidal volume can induce injury in otherwise healthy lungs. However, it remains controversial whether injurious ventilation per se, without preceding lung injury, can initiate cytokine-mediated pulmonary inflammation. To address this, we developed an in vivo mouse model of acute lung injury produced by high tidal volume (Vt) ventilation. Anesthetized C57BL6 mice were ventilated at high Vt (34.5 ± 2.9 ml/kg, mean ± SD) for a duration of 156 ± 17 min until mean blood pressure fell below 45 mmHg ( series 1); high Vt for 120 min ( series 2); or low Vt (8.8 ± 0.5 ml/kg) for 120 or 180 min ( series 3). High Vt produced progressive lung injury with a decrease in respiratory system compliance, increase in protein concentration in lung lavage fluid, and lung pathology showing hyaline membrane formation. High-Vt ventilation was associated with increased TNF-α in lung lavage fluid at the early stage of injury ( series 2) but not the later stage ( series 1). In contrast, lavage fluid macrophage inflammatory protein-2 (MIP-2) was increased in all high-Vt animals. Lavage fluid from high-Vt animals contained bioactive TNF-α by WEHI bioassay. Low-Vt ventilation induced minimal changes in physiology and pathology with negligible TNF-α and MIP-2 proteins and TNF-α bioactivity. These results demonstrate that high-Vt ventilation in the absence of underlying injury induces intrapulmonary TNF-α and MIP-2 expression in mice. The apparently transient nature of TNF-α upregulation may help explain previous controversy regarding the involvement of cytokines in ventilator-induced lung injury.

scholarly journals Resolvin D1 Alleviates Ventilator-Induced Lung Injury in Mice by Activating PPARγ/NF-κB Signaling Pathway

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Haifa Xia ◽  
Jingxu Wang ◽  
Shujun Sun ◽  
Fuquan Wang ◽  
Yiyi Yang ◽  
...  
Keyword(s):  
Lung Injury ◽  
Protective Effect ◽  
Tidal Volume ◽  
Signaling Pathways ◽  
Lung Tissue ◽  
Fatty Acid Derivative ◽  
High Tidal Volume ◽  
Treatment Modalities ◽  
Resolvin D1 ◽  
Ventilator Induced Lung Injury

As one of the basic treatment modalities in the intensive care unit (ICU), mechanical ventilation can cause or aggravate acute lung injury or ventilator-induced lung injury (VILI). Resolvin D1 (RvD1) is an endogenous polyunsaturated fatty acid derivative with strong anti-inflammatory action. In this study, we explored if RvD1 possesses a protective effect on VILI. Mice were ventilated with high tidal volume (40 mL/kg, HVT) for 4 h and were then intraperitoneally administered RvD1 at the beginning of high tidal volume ventilation and given GW9662 (a PPAR-γ antagonist) intraperitoneally 30 min before ventilation. RvD1 attenuated VILI, as evidenced by improved oxygenation and reduced histological injury, compared with HVT -induced lung injury. Similarly, it could ameliorate neutrophil accumulation and production of proinflammatory cytokines in lung tissue. In contrast, the protective effect of RvD1 on lung tissue could be reversed by GW9662. RvD1 mitigated VILI by activating peroxisome proliferator-activated receptor gamma (PPAR-γ) and inhibiting nuclear factor-kappa B (NF-κB) signaling pathways in mice. In conclusion, RvD1 could reduce the inflammatory response in VILI by activating PPAR-γ and inhibiting NF-κB signaling pathways.

scholarly journals Ventilator-induced lung-injury in mouse models: Is there a trap?

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Jon Petur Joelsson ◽  
Saevar Ingthorsson ◽  
Jennifer Kricker ◽  
Thorarinn Gudjonsson ◽  
Sigurbergur Karason
Keyword(s):  
Mechanical Ventilation ◽  
Lung Injury ◽  
Mouse Models ◽  
Mechanical Strain ◽  
Acute Injury ◽  
In Vivo Studies ◽  
Cellular Interactions ◽  
Ventilator Induced Lung Injury

AbstractVentilator-induced lung injury (VILI) is a serious acute injury to the lung tissue that can develop during mechanical ventilation of patients. Due to the mechanical strain of ventilation, damage can occur in the bronchiolar and alveolar epithelium resulting in a cascade of events that may be fatal to the patients. Patients requiring mechanical ventilation are often critically ill, which limits the possibility of obtaining patient samples, making VILI research challenging. In vitro models are very important for VILI research, but the complexity of the cellular interactions in multi-organ animals, necessitates in vivo studies where the mouse model is a common choice. However, the settings and duration of ventilation used to create VILI in mice vary greatly, causing uncertainty in interpretation and comparison of results. This review examines approaches to induce VILI in mouse models for the last 10 years, to our best knowledge, summarizing methods and key parameters presented across the studies. The results imply that a more standardized approach is warranted.

scholarly journals Inhibition of Poly(Adenosine Diphosphate–Ribose) Polymerase Attenuates Ventilator-induced Lung Injury

2008 ◽  
Vol 108 (2) ◽  
pp. 261-268 ◽  
Author(s):  
Rosanna Vaschetto ◽  
Jan W. Kuiper ◽  
Shyh Ren Chiang ◽  
Jack J. Haitsma ◽  
Jonathan W. Juco ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Lung Injury ◽  
Tidal Volume ◽  
Interleukin 6 ◽  
Inflammatory Responses ◽  
Adenosine Diphosphate ◽  
High Tidal Volume ◽  
Positive End Expiratory Pressure ◽  
Ventilator Induced Lung Injury ◽  
Pharmacologic Inhibition

Background Mechanical ventilation can induce organ injury associated with overwhelming inflammatory responses. Excessive activation of poly(adenosine diphosphate-ribose) polymerase enzyme after massive DNA damage may aggravate inflammatory responses. Therefore, the authors hypothesized that the pharmacologic inhibition of poly(adenosine diphosphate-ribose) polymerase by PJ-34 would attenuate ventilator-induced lung injury. Methods Anesthetized rats were subjected to intratracheal instillation of lipopolysaccharide at a dose of 6 mg/kg. The animals were then randomly assigned to receive mechanical ventilation at either low tidal volume (6 ml/kg) with 5 cm H2O positive end-expiratory pressure or high tidal volume (15 ml/kg) with zero positive end-expiratory pressure, in the presence and absence of intravenous administration of PJ-34. Results The high-tidal-volume ventilation resulted in an increase in poly(adenosine diphosphate-ribose) polymerase activity in the lung. The treatment with PJ-34 maintained a greater oxygenation and a lower airway plateau pressure than the vehicle control group. This was associated with a decreased level of interleukin 6, active plasminogen activator inhibitor 1 in the lung, attenuated leukocyte lung transmigration, and reduced pulmonary edema and apoptosis. The administration of PJ-34 also decreased the systemic levels of tumor necrosis factor alpha and interleukin 6, and attenuated the degree of apoptosis in the kidney. Conclusion The pharmacologic inhibition of poly(adenosine diphosphate-ribose) polymerase reduces ventilator-induced lung injury and protects kidney function.

scholarly journals Adipose-derived exosomes protect the pulmonary endothelial barrier in ventilator-induced lung injury by inhibiting the TRPV4/Ca2+ signaling pathway

2020 ◽  
Vol 318 (4) ◽  
pp. L723-L741 ◽  
Author(s):  
Qian Yu ◽  
Daoxin Wang ◽  
Xiaoting Wen ◽  
Xumao Tang ◽  
Di Qi ◽  
...  
Keyword(s):  
Lung Injury ◽  
Inflammatory Response ◽  
Transient Receptor Potential ◽  
Inflammatory Responses ◽  
Endothelial Barrier ◽  
Mouse Serum ◽  
Transient Receptor Potential Vanilloid ◽  
Ventilator Induced Lung Injury

Mechanical ventilation (MV) is the main supportive treatment of acute respiratory distress syndrome (ARDS), but it may lead to ventilator-induced lung injury (VILI). Large epidemiological studies have found that obesity was associated with lower mortality in mechanically ventilated patients with acute lung injury, which is known as “obesity paradox.” However, the effects of obesity on VILI are unknown. In the present study, wild-type mice were fed a high-fat diet (HFD) and ventilated with high tidal volume to investigate the effects of obesity on VILI in vivo, and pulmonary microvascular endothelial cells (PMVECs) were subjected to 18% cyclic stretching (CS) to further investigate its underlying mechanism in vitro. We found that HFD protects mice from VILI by alleviating the pulmonary endothelial barrier injury and inflammatory responses in mice. Adipose-derived exosomes can regulate distant tissues as novel adipokines, providing a new mechanism for cell-cell interactions. We extracted three adipose-derived exosomes, including HFD mouse serum exosome (S-Exo), adipose tissue exosome (AT-Exo), and adipose-derived stem cell exosome (ADSC-Exo), and further explored their effects on MV or 18% CS-induced VILI in vivo and in vitro. Administration of three exosomes protected against VILI by suppressing pulmonary endothelial barrier hyperpermeability, repairing the expression of adherens junctions, and alleviating inflammatory response in vivo and in vitro, accompanied by transient receptor potential vanilloid 4 (TRPV4)/Ca2+ pathway inhibition. Collectively, these data indicated that HFD-induced obesity plays a protective role in VILI by alleviating the pulmonary endothelial barrier injury and inflammatory response via adipose-derived exosomes, at least partially, through inhibiting the TRPV4/Ca2+ pathway.

Sign in / Sign up

Export Citation Format

Share Document