transforming-growth-factor-beta and Acute-Lung-Injury

Macrophages are highly plastic cells. Under different stimuli, macrophages can be polarized into several different subsets. Two main macrophage subsets have been suggested: classically activated or inflammatory (M1) macrophages and alternatively activated or anti-inflammatory (M2) macrophages. Macrophage polarization is governed by a highly complex set of regulatory networks. Many recent studies have shown that macrophages are key orchestrators in the pathogenesis of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and that regulation of macrophage polarization may improve the prognosis of ALI/ARDS. A further understanding of the mechanisms of macrophage polarization is expected to be helpful in the development of novel therapeutic targets to treat ALI/ARDS. Therefore, we performed a literature review to summarize the regulatory mechanisms of macrophage polarization and its role in the pathogenesis of ALI/ARDS.. A computer-based online search was performed using the PubMed database and Web of Science database for published articles concerning macrophages, macrophage polarization, and ALI/ARDS.. In this review, we discuss the origin, polarization, and polarization regulation of macrophages as well as the role of macrophage polarization in various stages of ARDS. According to the current literature, regulating the polarized state of macrophages might be a potential therapeutic strategy against ALI/ARDS.

Topics: Acute Lung Injury; Cell Polarity; Humans; JNK Mitogen-Activated Protein Kinases; Macrophages; NF-kappa B; Respiratory Distress Syndrome; Signal Transduction; Transforming Growth Factor beta

We investigated the effects of vegetable glycerin (VG), a main e-cigarette constituent, on endotoxin-induced acute lung injury (ALI). Mice received intratracheal administration of 30% VG in phosphate buffered saline (PBS) vehicle or only PBS (control) for 4 days. On Day 5, mice received an intratracheal instillation of lipopolysaccharide (LPS) (LPS group and VG + LPS group) or PBS (VG group and control group). Lung histopathology, expression of chemokine receptors, and regulatory signaling were analyzed 24 h after the Day 5 treatment. VG significantly increased ALI-associated histopathological and fibrotic changes in both the VG group and LPS-induced ALI mice (VG + LPS group). Immunohistochemistry (IHC) and western blot analyses revealed that VG administration resulted in upregulation of neutrophil markers [lymphocyte antigen 6 complex locus G6D (Ly6G) and myeloperoxidase (MPO)] as well as upregulation of the expression of transforming growth factor-β (TGF-β), a central mediator of fibrogenesis, in the lungs of both VG and VG + LPS groups. VG enhanced the expression of adhesion molecules [very late antigen 4 (VLA-4) and vascular cell adhesion molecule 1 (VCAM-1)] and increased activation of p38 mitogen-activated protein kinase (p38 MAPK) to prompt neutrophil recruitment in the lungs of mice with ALI. Intraperitoneal administration of a p38 inhibitor attenuated these histopathological changes significantly as well as VG-induced upregulation in expression of Ly6G, MPO, VLA-4, VCAM-1, TGF-β, and collagen-1 in mice with ALI. In conclusion, VG enhances neutrophil chemotaxis and fibrosis and it amplifies the inflammatory response associated with LPS-induced ALI in the lungs via enhancement of p38 MAPK activity.

Topics: Acute Lung Injury; Animals; Electronic Nicotine Delivery Systems; Fibrosis; Glycerol; Integrin alpha4beta1; Lipopolysaccharides; Lung; Mice; Neutrophils; p38 Mitogen-Activated Protein Kinases; Transforming Growth Factor beta; Vascular Cell Adhesion Molecule-1

Lung injury is the most common secondary complication of pancreatitis and pancreatic malignancy. Around 60-70% of pancreatitis-related deaths are caused by lung injury; however, there is no animal model of the inflammation-mediated progressive pulmonary pathological events that contribute to acute lung injury in chronic pancreatitis (CP). Hence, we developed an inflammation-mediated mouse model and studied the pathological events that have a critical role in promoting the pathogenesis of lung injury. Our proteomic analysis of lung tissue revealed neutrophil-associated induction of neutrophil gelatinase-associated lipocalin (NGAL) and myeloperoxidase enzyme, further supporting a role for neutrophils in promoting IL-18-associated lung injury. We show that neutrophils released IL-18-induced p-NF-κB along with profibrotic and oncogenic proteins like TTF1, PDX1, and SOX9 in lung tissues of a mouse model of chronic pancreatitis. We also show that neutrophil infiltration induces TGF-β and SMAD4 and activates epithelial cells to produce other profibrotic proteins like ZO-1 and MUC2, along with the fibroblast markers FGF-1 and αSMA, that cause mesenchymal transition and accumulation of extracellular matrix collagen. Most importantly, we present evidence that IL-18 inhibition significantly alleviates CP-induced lung injury. This was further established by the finding that IL-18 gene-deficient mice showed improved lung injury by inhibition of TGF-β and fibroblast to mesenchymal transition and reduced collagen accumulation. The present study suggests that inhibition of IL-18 may be a novel treatment for CP-associated induced acute lung injury.

Topics: Acute Lung Injury; Animals; Collagen; Inflammation; Interleukin-18; Lung; Mice; Neutrophil Infiltration; Pancreatitis, Chronic; Proteomics; Transforming Growth Factor beta

SARS-CoV-2 viremia is associated with increased acute lung injury (ALI) and mortality in children and adults. The mechanisms by which viral components in the circulation mediate ALI in COVID-19 remain unclear. We tested the hypothesis that the SARS-CoV-2 envelope (E) protein induces Toll-like receptor (TLR)-mediated ALI and lung remodeling in a model of neonatal COVID-19. Neonatal C57BL6 mice given intraperitoneal E protein injections revealed a dose-dependent increase in lung cytokines [interleukin 6 (

Topics: Acute Lung Injury; Animals; Child; COVID-19; Endothelial Cells; Glucocorticoids; Humans; Lipopolysaccharides; Mice; Mice, Inbred C57BL; SARS-CoV-2; Toll-Like Receptor 2; Toll-Like Receptor 4; Toll-Like Receptors; Transforming Growth Factor beta; Viral Envelope; Viremia

Acute lung injury (ALI) caused by sepsis is a life-threatening condition characterized by uncontrollable lung inflammation. The current study sought to investigate the mechanism of adipose-derived mesenchymal stem cell-derived exosomes (ADMSC-Exos) in attenuating sepsis-induced ALI through TGF-β secretion in macrophages.. Adipose-derived mesenchymal stem cell-derived exosomes (ADMSC-Exos) were extracted from ADMSCs and identified. Septic ALI mouse models were established via cecal ligation and puncture (CLP), followed by administration of ADMSC-Exos or sh-TGF-β lentiviral vector. Mouse macrophages (cell line RAW 264.7) were treated with lipopolysaccharide (LPS), co-cultured with Exos and splenic T cells, and transfected with TGF-β siRNA. The lung injury of CLP mice was evaluated, and levels of inflammatory indicators and macrophage markers were measured. The localization of macrophage markers and TGF-β was determined, and the level of TGF-β in lung tissues was measured. The effect of TGF-β knockdown on sepsis-induced ALI in CLP mice was evaluated, and the percentages of CD4+CD25+Foxp3+ Tregs in mononuclear cells/macrophages and Foxp3 levels in lung tissues/co-cultured splenic T cells were examined.. ADMSC-Exos were found to alleviate sepsis-induced ALI, inhibit inflammatory responses, and induce macrophages to secrete TGF-β in CLP mice. TGF-β silencing reversed the alleviating effect of ADMSC-Exos on sepsis-induced ALI. ADMSC-Exos also increased the number of Tregs in the spleen of CLP mice and promoted M2 polarization and TGF-β secretion in LPS-induced macrophages. After knockdown of TGF-β in macrophages in the co-culture system, the number of Tregs decreased, suggesting that ADMSC-Exos increased the Treg number by promoting macrophages to secrete TGF-β.. Our findings suggest ADMSC-Exos can effectively alleviate sepsis-induced ALI in CLP mice by promoting TGF-β secretion in macrophages.

Topics: Acute Lung Injury; Animals; Exosomes; Forkhead Transcription Factors; Lipopolysaccharides; Macrophages; Mesenchymal Stem Cells; Mice; Sepsis; Transforming Growth Factor beta

This study was conducted to investigate the role of Tenascin-C (TNC) in paraquat (PQ)-induced lung injury in vivo and in vitro and explore its related mechanism during this process. Six- to eight-week-old male C57BL/6 mice were injected with 30 mg/kg PQ by intraperitoneal injection and sacrificed on 2 days, 7 days, 14 days, and 28 days after PQ administration. In vivo, we detected the expression of TNC at all time points of lung tissues in mice by reverse transcription-quantitative-polymerase chain reaction, western blotting, and immunohistochemistry. Expression of TLR4, NF-κB p65, TGF-β1, and α-SMA in lung tissues have also been tested. In vitro, siRNA was used to knock down TNC expression in A549 cells and TLR4, NF-κB p65, and TGF-β1 expressions were examined after PQ exposure. TNC expression increased in both lung tissues of mice model and A549 cells after PQ administration. In vivo, TNC mostly located at the extracellular matrix of thickened alveolar septum, especially at sites of injury, together with the increasing of TLR4, NF-κB p65, TGF-β1, and α-SMA. In vitro, PQ exposure also increased the expressions of TLR4, NF-κB p65, and TGF-β1 in A549 cells, but knocking down TNC gene expression obviously down-regulated the expressions of TLR4, NF-κB p65, NF-κB Pp65, and TGF-β1. The results of this study demonstrate, for the first time, that TNC participates in the development of lung injury induced by PQ poisoning. The role of TNC in this process is closely related to TLR4 and TGF-β signaling pathways.

Topics: Acute Lung Injury; Animals; Biomarkers; Herbicides; Humans; Male; Mice; Mice, Inbred C57BL; Paraquat; Signal Transduction; Tenascin; Toll-Like Receptor 4; Transforming Growth Factor beta

The acute respiratory distress syndrome (ARDS) is a major healthcare problem, accounting for significant mortality and long-term disability. Approximately 25% of patients with ARDS will develop an overexuberant fibrotic response, termed fibroproliferative ARDS (FP-ARDS) that portends a poor prognosis and increased mortality. The cellular pathological processes that drive FP-ARDS remain incompletely understood. We have previously shown that the transmembrane receptor-type tyrosine phosphatase protein tyrosine phosphatase-α (PTPα) promotes pulmonary fibrosis in preclinical murine models through regulation of transforming growth factor-β (TGF-β) signaling. In this study, we examine the role of PTPα in the pathogenesis of FP-ARDS in a preclinical murine model of acid (HCl)-induced acute lung injury. We demonstrate that although mice genetically deficient in PTPα (

Topics: Acute Lung Injury; Animals; Lung; Mice; Phosphoric Monoester Hydrolases; Pulmonary Fibrosis; Receptor-Like Protein Tyrosine Phosphatases, Class 4; Respiratory Distress Syndrome; Transforming Growth Factor beta

Acute lung injury (ALI) increases sepsis morbidity and mortality. LncRNA H19 plays a critical role in sepsis. miR-107 is highly-expressed and TGFβ type III receptor (TGFBR3) is poorly-expressed in sepsis, yet their roles in sepsis development require further investigation. This study aimed to investigate the mechanism of H19 in alleviating sepsis-induced ALI through the miR-107/TGFBR3 axis.. Mice were intravenously injected with Ad-H19 adenovirus vector or control vector one week before establishing the mouse model of cecal ligation and puncture (CLP). Pulmonary microvascular endothelial cells (PMVECs) were transfected with oe-H19 or oe-NC plasmids and then stimulated by lipopolysaccharide (LPS). Lung injury was assessed via hematoxylin-eosin staining, measurement of wet-to-dry (W/D) ratio, and TUNEL staining. Levels of H19, miR-107, and TGFBR3 were determined by RT-qPCR. Apoptosis of PMVECs was evaluated by flow cytometry. Levels of Bax and Bcl-2 in lung tissues and PMVECs were measured using Western blot. Total protein concentration and the number of total cells, neutrophils, and macrophages in bronchoalveolar lavage fluid (BALF) were quantified. Levels of TNF-α, IL-1β, IL-6, and IL-10 in BALF, lung tissues, and PMVECs were measured by ELISA. Cross-linking relationships among H19, miR-107 and TGFBR3 were verified by dual-luciferase and RIP assays.. H19 was poorly-expressed in CLP-operated mice. H19 overexpression attenuated sepsis-induced ALI, which was manifested with complete alveolar structure, decreased lung injury score and lung W/D ratio, and inhibited apoptosis in CLP-operated mice, which was manifested with decreased number of TUNEL-positive cells and Bax level and increased Bcl-2 level. CLP-operated mice had increased concentration of total protein and number of total cells, neutrophils, and macrophages in BALF, which was nullified by H19 overexpression. H19 overexpression declined levels of TNF-α, IL-1β, and IL-6 and elevated IL-10 levels. H19 inhibited LPS-induced PMVEC apoptosis and pro-inflammatory cytokine production. H19 targeted TGFBR3 as the ceRNA of miR-107. miR-107 overexpression or silencing TGFBR3 partially averted the inhibition of H19 overexpression on LPS-induced PMVEC apoptosis and pro-inflammatory cytokine production.. LncRNA H19 inhibited LPS-induced PMVEC apoptosis and pro-inflammatory cytokine production and attenuated sepsis-induced ALI by targeting TGFBR3 as the ceRNA of miR-107.

Topics: Acute Lung Injury; Animals; bcl-2-Associated X Protein; Endothelial Cells; Eosine Yellowish-(YS); Hematoxylin; Interleukin-10; Interleukin-6; Lipopolysaccharides; Lung; Mice; MicroRNAs; Proteoglycans; Receptors, Transforming Growth Factor beta; RNA, Long Noncoding; Sepsis; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Heparin-binding protein (HBP), as a granule protein secreted by polymorphonuclear neutrophils, participates in the pathophysiological process of sepsis. It has been reported that HBP is a biomarker of sepsis related to the severity of septic shock and organ dysfunction. HBP binds to vascular endothelial cells as a primary target site. However, it is still unclear whether HBP-binding protein receptors exist on the surface of endothelial cells. The effect of HBP on vascular permeability in sepsis and its mechanism needs to be explored. We conducted in vivo and in vitro studies and demonstrated that HBP binds to transforming growth factor-β receptor type 2 (TGF-β-R2) as a ligand. Glutathione S-transferase pull-down analysis revealed that HBP mainly interacts with the extracellular domain of TGF-β-R2. HBP induces acute lung injury and vascular leakage via activation of the TGF-β/SMAD2/3 signaling pathway. A permeability assay suggested that TGF-β-R2 is necessary for HBP-induced increased permeability. We also defined the role of HBP and its potential membrane receptor TGF-β-R2 in the blood-gas barrier in the pathogenesis of HBP-related acute lung injury.

Topics: Acute Lung Injury; Antimicrobial Cationic Peptides; Biomarkers; Blood Proteins; Endothelial Cells; Glutathione Transferase; Humans; Ligands; Receptors, Transforming Growth Factor beta; rho GTP-Binding Proteins; Sepsis; Signal Transduction; Smad Proteins; Transforming Growth Factor beta; Transforming Growth Factors

Acute lung injury (ALI) is a systemic inflammatory process. A large number of studies have shown that astaxanthin (ASTA) has strong anti-inflammatory effects and almost non-toxic side effects. The purpose of this study was to explore the effect of ASTA on lipopolysaccharide (LPS)-induced ALI in mice and its underlying mechanism. The result showed that compared with the LPS group, the expression levels of the respiratory resistance (Re), inspiratory resistance (Ri), dynamic lung compliance (Cdyn), wet/dry weight (W/D) ratio, albumin (BA/SA) ratio and myeloperoxidase (MPO) activity in the ASTA pretreatment group were significantly reduced, and total cell, neutrophil and macrophage counts were significantly decreased. HE staining results showed that alveolar interstitial edema, bleeding and erythrocyte exudation were reduced. Compared with the LPS group, the percentage of Th17 cells and the content of interleukin (IL)-17 and tumor necrosis factor-α (TNF-α) in the ASTA pretreatment group were significantly decreased, while the content of the transforming growth factor (TGF)-β and the percentage of Treg cells were significantly increased. Western blot analysis showed that ASTA could up-regulate the expression level of the suppressor of cytokine signaling-3 (SOCS3) and down-regulate the expression levels of phosphorylated Janus kinase 2 (p-JAK2), phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in lung tissue. The results showed that ASTA had a protective effect on LPS-induced acute lung injury in mice, and its protective mechanism was through activating the SOCS3/JAK2/STAT3 signaling pathway, promoting Treg cell differentiation and reducing inflammatory reactions and Th17 cell differentiation, which provided a theoretical basis for the clinical treatment of ALI.

Topics: Acute Lung Injury; Animals; Inflammation; Janus Kinase 2; Lipopolysaccharides; Lung; Mice; Signal Transduction; Suppressor of Cytokine Signaling 3 Protein; Transforming Growth Factor beta

Acute respiratory distress syndrome (ARDS) is a serious inflammatory lung disorder and a complication of SARS-CoV-2 infection. In patients with severe SARS-CoV-2 infection, the transition to ARDS is principally due to the occurrence of a cytokine storm and an exacerbated inflammatory response. The effectiveness of ultra-micronized palmitoylethanolamide (PEA-um) during the earliest stage of COVID-19 has already been suggested. In this study, we evaluated its protective effects as well as the effectiveness of its congener, 2-pentadecyl-2-oxazoline (PEA-OXA), using in vitro models of acute lung injury. In detail, human lung epithelial cells (A549) activated by polyinosinic-polycytidylic acid (poly-(I:C)) or Transforming Growth Factor-beta (TGF-β) were treated with PEA-OXA or PEA. The release of IL-6 and the appearance of Epithelial-Mesenchymal Transition (EMT) were measured by ELISA and immunofluorescence assays, respectively. A possible mechanism of action for PEA-OXA and PEA was also investigated. Our results showed that both PEA-OXA and PEA were able to counteract poly-(I:C)-induced IL-6 release, as well as to revert TGF-β-induced EMT. In addition, PEA was able to produce an "entourage" effect on the levels of the two endocannabinoids AEA and 2-AG, while PEA-OXA only increased PEA endogenous levels, in poly-(I:C)-stimulated A549 cells. These results evidence for the first time the superiority of PEA-OXA over PEA in exerting protective effects and point to PEA-OXA as a new promising candidate in the management of acute lung injury.

Topics: Acute Lung Injury; COVID-19; Humans; Interleukin-6; SARS-CoV-2; Transforming Growth Factor beta

Lipopolysaccharide (LPS) induces stress inflammation and apoptosis. Pulmonary epithelial cell apoptosis, which accelerates the progression of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), is the leading cause of mortality in patients with ALI/ARDS. The nephroblastoma overexpressed protein (CCN3), an inflammatory modulator, is reported to be a biomarker in ALI. Using the LPS-induced ALI model, this study investigated the expression of CCN3 and its possible molecular mechanism in lung alveolar epithelial cell inflammation and apoptosis. Our data revealed that LPS treatment greatly increased the level of CCN3 in A549 cells. The A549 cells were transfected with specific CCN3 small interfering RNA (siRNA) using transfection reagent. CCN3 siRNA not only largely attenuated the expressions of the inflammatory cytokines interleukin (IL)-1β and transforming growth factor (TGF)-β1, but also reduced the apoptotic rate of the AEC II cells and affected the expressions of the apoptosis-associated proteins (Bcl-2 and caspase-3). Furthermore, CCN3 knockdown greatly inhibited the activation of nuclear factor-κB p65 in A549 cells. In addition, TGF-β/p-Smad inhibitor (TP0427736) and NF-κB inhibitor (PDTC) significantly attenuated the expression level of CCN3 in A549 cells. In conclusion, our data indicated that CCN3 siRNA affected downstream signal through TGF-β/ p-Smad or NF-κB pathway, leading to the inhibition of cell inflammation and apoptosis in human alveolar epithelial cells.

Topics: A549 Cells; Acute Lung Injury; Alveolar Epithelial Cells; Apoptosis; Caspase 3; Gene Knockdown Techniques; Humans; Inflammation; Interleukin-1beta; Lipopolysaccharides; Lung; Nephroblastoma Overexpressed Protein; NF-kappa B; Proto-Oncogene Proteins c-bcl-2; RNA, Small Interfering; Signal Transduction; Smad Proteins; Transforming Growth Factor beta

CD4. To investigate whether HMGB1 aggravates ALI by suppressing immunosuppressive function of Tregs.. Anti-HMGB1 antibody and recombinant mouse HMGB1 (rHMGB1) were administered in lipopolysaccharide (LPS)-induced ALI mice and polarized LPS-primed Tregs in vitro. The Tregs pre-stimulated with or without rHMGB1 were adoptively transferred to ALI mice and depleted by Diphtheria toxin (DT). For coculture experiment, isolated Tregs were first pre-stimulated with or without rHMGB1 or anti-HMGB1 antibody, then they were cocultured with bone marrow-derived macrophages (BMMs) under LPS stimulation.. Tregs protected against acute lung pathological injury. HMGB1 modulated the suppressive function of Tregs as follows: reduction in the number of the cells and the activity of Tregs, the secretion of anti-inflammatory cytokines (IL-10, TGF-β) from Tregs, the production of IL-2 from CD4. HMGB1 could aggravate LPS induced-ALI through suppressing the activity and function of Tregs.

Topics: Acute Lung Injury; Animals; Cytokines; Disease Models, Animal; HMGB1 Protein; Interleukin-10; Lipopolysaccharides; Lung; Macrophages; Male; Mice; Mice, Inbred C57BL; T-Lymphocytes, Regulatory; Transforming Growth Factor beta

This study aims to explore the roles of miR-145/TGFBR2 axis in sepsis-induced acute lung injury. Here, RNA-sequencing assay showed that miR-145 was significantly decreased in exosomes from sepsis patient blood samples. And miR-145 was decreased but TGFBR2 was increased in LPS-treated mice lung tissues or BEAS-2B cells in a time-dependent manner. Mechanistically, TGFBR2 was identified as a direct target of miR-145 and the downstream effector Smad3 was also suppressed in BEAS-2B cells with miR-145 overexpression. Pre-injection or post-injection of miR-145 agomir following LPS treatment attenuated LPS-induced inflammation, characterized as the downregulation of IL-2 and TNF-α secretion and ameliorate sepsis, and prolonged the overall survival of septic mice with lung injury. Additionally, TGFBR2 overexpression partially abrogated miR-145-mediated inhibition on LPS-induced inflammation and sepsis-induced acute lung injury. Importantly, TGF-β (Transforming growth factor-β) and miR-145 level displayed a negative correlation in sepsis patients. Thus, these results suggest that miR-145 could ameliorate sepsis-induced lung injury via inhibiting TGFBR2 signaling.

Topics: Acute Lung Injury; Animals; Cell Line; Down-Regulation; Humans; Inflammation; Interleukin-2; Mice; MicroRNAs; Receptor, Transforming Growth Factor-beta Type II; Sepsis; Signal Transduction; Smad3 Protein; Transforming Growth Factor beta

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia that mainly affects the elderly. Several reports have demonstrated that aging is involved in the underlying pathogenic mechanisms of IPF. α-Klotho (KL) has been well characterized as an "age-suppressing" hormone and can provide protection against cellular senescence and oxidative stress. In this study, KL levels were assessed in human plasma and primary lung fibroblasts from patients with idiopathic pulmonary fibrosis (IPF-FB) and in lung tissue from mice exposed to bleomycin, which showed significant downregulation when compared with controls. Conversely, transgenic mice overexpressing KL were protected against bleomycin-induced lung fibrosis. Treatment of human lung fibroblasts with recombinant KL alone was not sufficient to inhibit transforming growth factor-β (TGF-β)-induced collagen deposition and inflammatory marker expression. Interestingly, fibroblast growth factor 23 (FGF23), a proinflammatory circulating protein for which KL is a coreceptor, was upregulated in IPF and bleomycin lungs. To our surprise, FGF23 and KL coadministration led to a significant reduction in fibrosis and inflammation in IPF-FB; FGF23 administration alone or in combination with KL stimulated KL upregulation. We conclude that in IPF downregulation of KL may contribute to fibrosis and inflammation and FGF23 may act as a compensatory antifibrotic and anti-inflammatory mediator via inhibition of TGF-β signaling. Upon restoration of KL levels, the combination of FGF23 and KL leads to resolution of inflammation and fibrosis. Altogether, these data provide novel insight into the FGF23/KL axis and its antifibrotic/anti-inflammatory properties, which opens new avenues for potential therapies in aging-related diseases like IPF.

Topics: Acute Lung Injury; Aged; Animals; Bleomycin; Case-Control Studies; Collagen; Female; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Fibroblasts; Gene Expression Regulation; Glucuronidase; Humans; Idiopathic Pulmonary Fibrosis; Kidney Function Tests; Klotho Proteins; Lung; Male; Mice; Mice, Transgenic; Middle Aged; Primary Cell Culture; Respiratory Function Tests; Signal Transduction; Transforming Growth Factor beta

Staphylococcal enterotoxin B (SEB) is a potent superantigen produced by Staphylococcus aureus that triggers a strong immune response, characterized by cytokine storm, multi-organ failure, and often death. When inhaled, SEB can cause acute lung injury (ALI) and respiratory failure. In this study, we investigated the effect of resveratrol (RES), a phytoallexin, on SEB-driven ALI and mortality in mice. We used a dual-exposure model of SEB in C3H/HeJ mice, which caused 100% mortality within the first 5 days of exposure, and treatment with RES resulted in 100% survival of these mice up to 10 days post-SEB exposure. RES reduced the inflammatory cytokines in the serum and lungs, as well as T cell infiltration into the lungs caused by SEB. Treatment with RES also caused increased production of transforming growth factor-beta (TGF-β) in the blood and lungs. RES altered the miRNA profile in the immune cells isolated from the lungs. Of these, miR-193a was strongly induced by SEB and was down-regulated by RES treatment. Furthermore, transfection studies and pathway analyses revealed that miR-193a targeted several molecules involved in TGF-β signalling (TGFβ2, TGFβR3) and activation of apoptotic pathways death receptor-6 (DR6). Together, our studies suggest that RES can effectively neutralize SEB-mediated lung injury and mortality through potential regulation of miRNA that promote anti-inflammatory activities.

Topics: Acute Lung Injury; Animals; Base Sequence; Bronchoalveolar Lavage Fluid; Cytokines; Down-Regulation; Enterotoxins; Female; Lung; Mice; Mice, Inbred C3H; MicroRNAs; Protective Agents; Resveratrol; Signal Transduction; Transforming Growth Factor beta

Acute liver injury (ALI) is highly lethal acute liver failure caused by different etiologies. Transforming growth factor β (TGF-β) is a multifunctional cytokine and a well-recognized inducer of apoptotic and necrotic cell death in hepatocytes. Latent TGF-β is activated partly through proteolytic cleavage by a serine protease plasma kallikrein (PLK) between the R58 and L59 residues of its propeptide region. Recently, we developed a specific monoclonal antibody to detect the N-terminal side LAP degradation products ending at residue R58 (R58 LAP-DPs) that reflect PLK-dependent TGF-β activation. This study aimed to explore the potential roles of PLK-dependent TGF-β activation in the pathogenesis of ALI. We established a mouse ALI model via the injection of anti-Fas antibodies (Jo2) and observed increases in the TGF-β1 mRNA level, Smad3 phosphorylation, TUNEL-positive apoptotic hepatocytes and R58-positive cells in the liver tissues of Jo2-treated mice. The R58 LAP-DPs were observed in/around F4/80-positive macrophages, while macrophage depletion with clodronate liposomes partly alleviated the Jo2-induced liver injury. Blocking PLK-dependent TGF-β activation using either the serine proteinase inhibitor FOY305 or the selective PLK inhibitor PKSI-527 or blocking the TGF-β receptor-mediated signaling pathway using SB431542 significantly prevented Jo2-induced hepatic apoptosis and mortality. Furthermore, similar phenomena were observed in the mouse model of ALI with the administration of acetaminophen (APAP). In summary, R58 LAP-DPs reflecting PLK-dependent TGF-β activation may serve as a biomarker for ALI, and targeting PLK-dependent TGF-β activation has potential as a therapeutic strategy for ALI.

Topics: Acetaminophen; Acute Lung Injury; Animals; Antibodies, Monoclonal; Benzamides; Biomarkers; Chemical and Drug Induced Liver Injury; Dioxoles; Disease Models, Animal; fas Receptor; Latent TGF-beta Binding Proteins; Macrophages; Male; Mice, Inbred C57BL; Plasma Kallikrein; Receptors, Transforming Growth Factor beta; Transforming Growth Factor beta

Acute lung injury (ALI) is a severe inflammatory disease, for which no specific treatment exists. The decreased ratio of regulatory T cells (CD4

Topics: Acute Lung Injury; Animals; Disease Models, Animal; Interleukin-2 Receptor alpha Subunit; Lipopolysaccharides; Lung; Lymphocyte Depletion; Male; Mice; Mice, Inbred C57BL; T-Lymphocytes, Regulatory; Th17 Cells; Transforming Growth Factor beta

Acute respiratory distress syndrome constitutes a significant disease burden with regard to both morbidity and mortality. Current therapies are mostly supportive and do not address the underlying pathophysiologic mechanisms. Removal of protein-rich alveolar edema-a clinical hallmark of acute respiratory distress syndrome-is critical for survival. Here, we describe a transforming growth factor (TGF)-β-triggered mechanism, in which megalin, the primary mediator of alveolar protein transport, is negatively regulated by glycogen synthase kinase (GSK) 3β, with protein phosphatase 1 and nuclear inhibitor of protein phosphatase 1 being involved in the signaling cascade. Inhibition of GSK3β rescued transepithelial protein clearance in primary alveolar epithelial cells after TGF-β treatment. Moreover, in a bleomycin-based model of acute lung injury, megalin

Topics: Acute Lung Injury; Animals; Glycogen Synthase Kinase 3 beta; Low Density Lipoprotein Receptor-Related Protein-2; Lung; Mice, Inbred C57BL; Mice, Knockout; Pulmonary Alveoli; Pulmonary Edema; Respiratory Distress Syndrome; Transforming Growth Factor beta

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe inflammatory lung diseases. Methylprednisolone (MP) is a common drug against inflammation in clinic. In this study, we aim to investigate the protective effect of MP on ALI and potential mechanisms.. Respiratory physiologic function was significantly improved by MP treatment. Tissue injury and inflammation were ameliorated in the MP-treated group. After MP treatment, the number of M1 decreased and M2 increased in the lung. In in vitro experiment, MP promoted M2 polarization rather than M1. We then induced M1, M2a and M2c from bone marrow cells. M1 induced more Th17 while M2 induced more CD4. In conclusion, MP ameliorated ALI by promoting M2 polarization. M2, especially M2c, induced Tregs without any influence on Tregs immunosuppression function.

Topics: Acute Lung Injury; Animals; Blood Gas Analysis; Bronchoalveolar Lavage Fluid; Cell Differentiation; Chemokines; Glucocorticoids; Inflammation; Interleukin-10; Lung; Macrophages; Male; Methylprednisolone; Mice, Inbred BALB C; Models, Biological; Organ Size; T-Lymphocytes, Regulatory; Transforming Growth Factor beta

Prolonged administration of an excessive dose of corticosteroids proved to be harmful for patients with acute lung injury (ALI). A previous study has found that repeated administration of an excessive dose of methylprednisolone reduced alveolar macrophages (AMs) in bronchoalveolar lavage fluid (BALF) with an unknown mechanism. This study aimed to investigate the effect of excessive use of dexamethasone (Dex) on BALF AMs in vitro. Transmission electron microscopy and DNA fragmentation analysis demonstrated that 10

Topics: Acute Lung Injury; Animals; Apoptosis; Bronchoalveolar Lavage Fluid; Dexamethasone; DNA Fragmentation; Dose-Response Relationship, Drug; Down-Regulation; Glucocorticoids; Interleukin-10; Interleukin-12; Lipopolysaccharides; Macrophages, Alveolar; Male; Microscopy, Electron, Transmission; Rats; Rats, Sprague-Dawley; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

To explore the possible mechanism and protective effect of BMSCs (bone mesenchymal stem cells) carrying superoxide dismutase (SOD) gene on mice with paraquat-induced acute lung injury.. To establish the cell line of BMSCs bringing SOD gene, lentiviral vector bringing SOD gene was built and co-cultured with BMSCs. A total of 100 BALB/c mice were randomly divided into five groups, namely Control group, poisoning group (PQ group) , BMSCs therapy group (BMSC group) , BMSCs-Cherry therapy group (BMSC-Cherry group) , BMSCs-SOD therapy group (BMSC-SOD group) . PQ poisoning model was produced by stomach lavaged once with 1 ml of 25 mg/kg PQ solution, and the equal volume of normal saline (NS) was given to Control group mice instead of PQ. The corresponding BMSCs therapy cell lines were delivered to mice through the tail vein of mice 4h after PQ treatment.Five mice of each group were sacrificed 3 d, 7 d, 14 d and 21 days after corresponding BMSCs therapy cell lines administration, and lung tissues of mice were taken to make sections for histological analysis. The serum levels of glutathione (GSH) , malondialdehyde (MDA) , SOD, and the levels of transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) in lung tissue were determined. The level of SOD was assayed by Westen-blot.. Compared with Control group, the early (3 days) levels of SOD protein in lung tissue of PQ group obviously decreased, and the late (21 days) levels of SOD obviously increased, while in therapy groups, that was higher than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Compared with Control group, the levels of plasma GSH and SOD of PQ group and each therapy group wae significantly lower than those in Control group, while in therapy groups, those were higher than those of PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) .Compared with Control group, the level of plasma MDA, TNF-α and TGF-β in PQ group and therapy groups were significantly higher, while in therapy groups, that was lower than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Lung biopsy showed that, the degree of lung tissue damage in each therapy group obviously reduced.. SOD is the key factor of the removal of reactive oxygen species (ROS) in cells, that can obviously inhibit the oxidative stress damage and the apoptosis induced by PQ, thus significantly increasing alveolar epithelial cell ability to fight outside harmful environment.

Topics: Acute Lung Injury; Animals; Antioxidants; Cell Line; Glutathione; Lung; Malondialdehyde; Mesenchymal Stem Cell Transplantation; Mice; Mice, Inbred BALB C; Oxidative Stress; Paraquat; Superoxide Dismutase; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Protein kinase Cζ (PKCζ) is highly expressed in the lung, where it plays several regulating roles in the pathogenesis of acute lung injury (ALI). Proliferation and differentiation of integrin β4

Topics: Acute Lung Injury; Animals; Bleomycin; Bronchoalveolar Lavage Fluid; Cell Death; Cell Movement; Cell Proliferation; Cell Separation; Compliance; Disease Models, Animal; Enzyme Activation; Epithelial Cells; Mice, Inbred C57BL; Models, Biological; Neutrophils; Permeability; Protein Kinase C; Protein Kinase Inhibitors; Pulmonary Fibrosis; Reactive Oxygen Species; Stem Cells; Transforming Growth Factor beta

As the eighth leading cause of annual mortality in the USA, influenza A viruses are a major public health concern. In 20% of patients, severe influenza progresses to acute lung injury (ALI). However, pathophysiological mechanisms underlying ALI development are poorly defined. We reported that, unlike wild-type (WT) C57BL/6 controls, influenza A virus-infected mice that are heterozygous for the F508del mutation in the cystic fibrosis transmembrane conductance regulator (HETs) did not develop ALI. This effect was associated with higher IL-6 and alveolar macrophages (AMs) at 6 days postinfection (d.p.i.) in HET bronchoalveolar lavage fluid (BALF). In the present study, we found that HET AMs were an important source of IL-6 at 6 d.p.i. Infection also induced TGF-β production by HET but not WT mice at 2 d.p.i. TGF-β neutralization at 2 d.p.i. (TGF-N) significantly reduced BALF IL-6 in HETs at 6 d.p.i. Neither TGF-N nor IL-6 neutralization at 4 d.p.i. (IL-6-N) altered postinfection weight loss or viral replication in either mouse strain. However, both treatments increased influenza A virus-induced hypoxemia, pulmonary edema, and lung dysfunction in HETs to WT levels at 6 d.p.i. TGF-N and IL-6-N did not affect BALF AM and neutrophil numbers but attenuated the CXCL-1/keratinocyte chemokine response in both strains and reduced IFN-γ production in WT mice. Finally, bone marrow transfer experiments showed that HET stromal and myeloid cells are both required for protection from ALI in HETs. These findings indicate that TGF-β-dependent production of IL-6 by AMs later in infection prevents ALI development in influenza A virus-infected HET mice.

Topics: Acute Lung Injury; Animals; Bronchoalveolar Lavage Fluid; Cystic Fibrosis Transmembrane Conductance Regulator; Immunity, Innate; Influenza A virus; Interleukin-6; Macrophages, Alveolar; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Inbred CFTR; Orthomyxoviridae Infections; Sequence Deletion; Transforming Growth Factor beta

The aim of this study is to show the effect of a new mechanism on endothelin (ET) receptors in the physiopathology of diabetes-related pulmonary injury. We tested the hypothesis that dual ET-1 receptor antagonism via bosentan can reverse diabetes-induced lung injury.. The rats (24 male) were separated into four groups: group 1 (HEALTHY): Control group; group 2 (DM): Streptozotocin 60 mg/kg (i.p.); group 3 (DM + BOS-1): Diabetes + bosentan 50 mg/kg per-os; group 4 (DM + BOS-2): Diabetes + bosentan 100 mg/kg per-os. The bosentan treatment was initiated immediately after the onset of STZ-induced diabetes and continued for 6 weeks.. In the treatment group, SOD activity was significantly increased, although GSH and MDA levels and TNF-α and TGF-β gene expression were decreased. Bosentan 50 mg/kg and bosentan 100 mg/kg showed a significantly down-regulatory effect on ET-1, ET-A, and ET-B mRNA expression.. In conclusion, increased endothelin levels in the lung associated with diabetes may be one cause of endothelial dysfunction, cytokine increase, and oxidant/antioxidant imbalance in the pathogenesis of complications that may develop during diabetes. With its multiple effects, bosentan therapy may be an effective option against complications that may develop in association with diabetes.

Topics: Acute Lung Injury; Animals; Bosentan; Diabetes Mellitus, Experimental; Endothelin Receptor Antagonists; Glutathione; Lung; Male; Malondialdehyde; Oxidative Stress; Rats; Rats, Wistar; Sulfonamides; Superoxide Dismutase; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Sepsis-induced inflammation of the lung leads to acute respiratory distress syndrome (ARDS), which may trigger persistent fibrosis. The pathology of ARDS is complex and poorly understood, and the therapeutic approaches are limited. We used a baboon model of Escherichia coli sepsis that mimics the complexity of human disease to study the pathophysiology of ARDS. We performed extensive biochemical, histological, and functional analyses to characterize the disease progression and the long-term effects of sepsis on the lung structure and function. Similar to humans, sepsis-induced ARDS in baboons displays an early inflammatory exudative phase, with extensive necrosis. This is followed by a regenerative phase dominated by proliferation of type 2 epithelial cells, expression of epithelial-to-mesenchymal transition markers, myofibroblast migration and proliferation, and collagen synthesis. Baboons that survived sepsis showed persistent inflammation and collagen deposition 6-27 months after the acute episodes. Long-term survivors had almost double the amount of collagen in the lung as compared with age-matched control animals. Immunostaining for procollagens showed persistent active collagen synthesis within the fibroblastic foci and interalveolar septa. Fibroblasts expressed markers of transforming growth factor-β and platelet-derived growth factor signaling, suggesting their potential role as mediators of myofibroblast migration and proliferation, and collagen deposition. In parallel, up-regulation of the inhibitors of extracellular proteases supports a deregulated matrix remodeling that may contribute to fibrosis. The primate model of sepsis-induced ARDS mimics the disease progression in humans, including chronic inflammation and long-lasting fibrosis. This model helps our understanding of the pathophysiology of fibrosis and the testing of new therapies.

Topics: Acute Lung Injury; Animals; Collagen; Disease Models, Animal; Escherichia coli; Fibrosis; Humans; Inflammation; Lung; Papio; Respiratory Distress Syndrome; Sepsis; Signal Transduction; Transforming Growth Factor beta

TGF-β is a pathogenic factor in patients with acute respiratory distress syndrome (ARDS), a condition characterized by alveolar edema. A unique TGF-β pathway is described, which rapidly promoted internalization of the αβγ epithelial sodium channel (ENaC) complex from the alveolar epithelial cell surface, leading to persistence of pulmonary edema. TGF-β applied to the alveolar airspaces of live rabbits or isolated rabbit lungs blocked sodium transport and caused fluid retention, which--together with patch-clamp and flow cytometry studies--identified ENaC as the target of TGF-β. TGF-β rapidly and sequentially activated phospholipase D1, phosphatidylinositol-4-phosphate 5-kinase 1α, and NADPH oxidase 4 (NOX4) to produce reactive oxygen species, driving internalization of βENaC, the subunit responsible for cell-surface stability of the αβγENaC complex. ENaC internalization was dependent on oxidation of βENaC Cys(43). Treatment of alveolar epithelial cells with bronchoalveolar lavage fluids from ARDS patients drove βENaC internalization, which was inhibited by a TGF-β neutralizing antibody and a Tgfbr1 inhibitor. Pharmacological inhibition of TGF-β signaling in vivo in mice, and genetic ablation of the nox4 gene in mice, protected against perturbed lung fluid balance in a bleomycin model of lung injury, highlighting a role for both proximal and distal components of this unique ENaC regulatory pathway in lung fluid balance. These data describe a unique TGF-β-dependent mechanism that regulates ion and fluid transport in the lung, which is not only relevant to the pathological mechanisms of ARDS, but might also represent a physiological means of acutely regulating ENaC activity in the lung and other organs.

Topics: Acute Lung Injury; Adenosine Triphosphatases; Adult; Aged; Animals; Epithelial Sodium Channels; Female; Gene Expression Regulation; Humans; Ions; Lung; Male; Mice; Mice, Knockout; Middle Aged; Perfusion; Phospholipase D; Phosphotransferases (Alcohol Group Acceptor); Pulmonary Alveoli; Rabbits; Reactive Oxygen Species; Respiratory Distress Syndrome; Transforming Growth Factor beta

Topics: Acute Lung Injury; Animals; Epithelial Sodium Channels; Female; Gene Expression Regulation; Humans; Male; Transforming Growth Factor beta

Acute lung injury is caused by many factors including acute pancreatitis. There is no specific therapy directed at underlying pathophysiological mechanisms for acute lung injury. Transforming growth factor-β (TGF-β) is involved in the resolution of lung injury in later phases of the disease. Some evidence exists demonstrating that TGF-β not only is involved in the late stages, but also contributes to lung injury early on in the progress of the disease. Acute pancreatitis was induced using ductal ligation in mice. TGF-β1, 2, and 3, TβRII, ALK-5, Smad2, 3, 4, and 7, and P-Smad2 expression in the lungs were analyzed at 9 and 24 h. We demonstrate that TGF- β1 levels in the lungs of mice with acute pancreatitis increase as early as 9 h after induction. We observed an increased expression of ALK-5 in acute pancreatitis at both 9 and 24 h. Inhibitory Smad7 expression was transiently increased at 9 h in acute pancreatitis, but reduced later at 24 h, with a concomitant increased nuclear translocation of phosphorylated Smad2. Our findings demonstrate activation of TGF-β signaling in the lungs as early as 24 h after acute pancreatitis, suggesting that TGF-β may represent a potential therapeutic candidate in acute pancreatitis-induced acute lung injury.

Topics: Acute Lung Injury; Animals; Disease Models, Animal; Disease Progression; Lung; Male; Mice; Mice, Inbred C57BL; Pancreatitis; Phosphorylation; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type I; Receptors, Transforming Growth Factor beta; Signal Transduction; Smad2 Protein; Time Factors; Transforming Growth Factor beta; Transforming Growth Factor beta1

Intravenous immunoglobulin (IVIG) therapy is used in inflammatory diseases but the use of immunoglobulin as a treatment for acute lung injury (ALI) has not been previously studied. Transforming growth factor beta (TGF-β) plays a critical role in the pathogenesis of of ALI. Therefore we examined the levels of TGF-β and lung inflammation scores in IVIG treated ALI models.. Intratracheal lipopolysacccharide was given to rats. Groups 1 and 3 received saline, whereas group 2 received IVIG. 24h later saline was given to groups 1 and 2 and IVIG to group 3. Blood samples and bronchoalveolar lavage (BAL) fluids were obtained from each group and sacrificed for pathological evaluation.. BAL TGF-β levels of groups 2 and 3 on day 30, were lower compared to their levels of day 2 (p=0.01, p=0.01). BAL TGF-β levels of groups 2 and 3 were lower than the levels of group 1 on day 30 (p=0.002, p=0.001). Pathological examination revealed that the inflammation scores of groups 2 and 3 on day 30, were lower than the scores of day 2 (p=0.02, p=0.01). Inflammation scores of group 2 were lower than group 1 on day 30 (p=0.02). Moderate fibrosis was seen in half of the rats from group 1 and one rat from group 2.. High-dose IVIG decreased lung inflammation scores and BAL TGF-β1 levels and this therapy would give even better results if it is given earlier.

Topics: Acute Lung Injury; Animals; Fibrosis; Humans; Immunoglobulins, Intravenous; Lipopolysaccharides; Lung; Male; Pneumonia; Rats; Rats, Wistar; Transforming Growth Factor beta

Paraquat (PQ) poisoning, with the lung as a primary target organ, is a devastating disease which irreversibly progresses to diffuse alveolitis followed by extensive lung fibrosis. In the present study, we aimed to investigate the effect of FTY720, an immune modulator, on PQ-induced lung injury in mice. C57BL/6 mice were randomized into four groups: 1) PQ group (n=12): mice was instilled with PQ (30 mg/kg, ip); 2) PQ+FTY720 group (n=12): animals received FTY720 (0.1mg/kg, ip) solution 2h after PQ exposure and twice a week for 4 consecutive weeks; 3) FTY720 group (n=5): FTY720 (0.1mg/kg, ip) was administrated twice a week for 4 consecutive weeks; and 4) Control group (n=10): same volumes of saline were injected. Mice were sacrificed on either day 3 or day 28 for histopathological, biochemical and immunohistochemical analyses of lung damage indicators. We found that FTY720 treatment attenuated PQ-induced acute lung injury and lung fibrosis as evaluated by histopathological changes and Ashcroft score. On day 3, FTY720 administration reduced PQ-induced increases in lung wet weight/body weight (LW/BW), total protein and cytokine levels including interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in bronchoalceolar lavage fluid (BALF). On day 28, the expressions of alpha-smooth muscle actin (α-SMA), transforming growth factor-beta (TGF-β) and vascular endothelial growth factor (VEGF) detected by immunohistochemistry, as well as the mRNA levels of α-SMA, Type-I Collagen and Type-III Collagen examined by Real-time PCR were down-regulated after FTY720 treatment. These results indicate that FTY720 could attenuate PQ-induced lung injury, but further investigation is necessary.

Topics: Actins; Acute Lung Injury; Animals; Body Weight; Bronchoalveolar Lavage Fluid; Collagen Type I; Collagen Type III; Disease Models, Animal; Fingolimod Hydrochloride; Interleukin-1beta; Interleukin-6; Lung; Lung Injury; Mice; Mice, Inbred C57BL; Paraquat; Propylene Glycols; Pulmonary Edema; Pulmonary Fibrosis; Sphingosine; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A

We have previously shown that diabetic rats are more susceptible to sepsis, but that the Acute lung injury (ALI) secondary to sepsis is less intense than in non-diabetics. In the present study, we further investigated the ALI-secondary to sepsis in diabetic rats and the effect of insulin treatment.. Diabetes was induced in male Wistar rats by alloxan and sepsis by cecal ligation and puncture surgery (CLP). Some diabetic rats were given neutral protamine Hagedorn (NPH) insulin (4 IU, s.c.) 2 h before CLP. Six h later, the lungs were examined for edema, cell infiltration and prostaglandin-E2 (PGE2) levels in the bronchoalveolar lavage (BAL).. The results confirmed that leukocyte infiltration and edema were milder in diabetic rats with sepsis. After insulin treatment, the lung inflammation in diabetics increased to levels comparable to the non-diabetics. The BAL concentration of PGE2 was also lower in diabetics with sepsis, and increased after insulin treatment. Sepsis was followed by early fibroblast activation in the lung parenchyma, evaluated by increased transforming growth factor (TGF)-β and smooth muscle actin (α-SMA) expression, as well as an elevated number of cells with myofibroblasts morphology. These events were significantly lower in diabetic rats and increased after insulin treatment.. The results show that insulin modulates the early phase of inflammation and myofibroblast differentiation in diabetic rats.

Topics: Actins; Acute Lung Injury; Alloxan; Animals; Bronchoalveolar Lavage Fluid; Cell Count; Diabetes Mellitus, Experimental; Dinoprostone; Edema; Insulin; Leukocytes; Male; Myofibroblasts; Pneumonia; Rats; Rats, Wistar; Sepsis; Specific Pathogen-Free Organisms; Transforming Growth Factor beta

To investigate whether heparin has a beneficial effect on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats, and to explore the possible underlying mechanisms.. Thirty-two adult Sprague-Dawley (SD) rats were randomly assigned into the control, heparin control, model, and heparin treatment groups, with 8 in each group. ALI rat model was reproduced by intratracheal instillation of LPS at a dose of 1 mg/kg. The rats in the control and heparin control groups received an equal volume of normal saline at the same times. The rats in the heparin control and heparin treatment groups were intravenously received 50 U/kg heparin every 1 hour after the induction of ALI. Animals were sacrificed 24 hours after LPS challenge. Bronchoalveolar lavage fluid (BALF) and lung tissue samples were collected. Histopathological evaluation, lung wet/dry (W/D) ratio, malondialdehyde (MDA), nitric oxide (NO) and myeloperoxidase (MPO) were analyzed. Enzyme-linked immunosorbent assay (ELISA) was used to measure the concentration of inflammatory factor in BALF. Expression of inducible nitric oxide synthase (iNOS) mRNA in the lung of rats was measured by reverse transcription-polymerase chain reaction (RT-PCR). Western Blot was used to determine the expression of transforming growth factor-β1 (TGF-β1) and phosphorylation of Smad in the lung tissues. The expression of iNOS in lung was determined by immunohistochemistry.. In the control and heparin control groups, lung tissue showed a normal structure and clear pulmonary alveoli under a light microscope. In the model group, ALI characters such as extensive thickening of the alveolar wall, significant infiltration of inflammatory cells, demolished structure of pulmonary alveoli, and hemorrhage were found. In the heparin treatment group, heparin treatment markedly alleviated LPS-induced these pathological changes in lung. Compared with control and heparin control groups, lung W/D ratio, lung MDA, NO and MPO levels, and tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in BALF in the model group were increased significantly. Compared with the model group, lung W/D ratio, lung MDA, NO and MPO levels, and TNF-α and IL-6 in BALF in the heparin treatment group were significantly decreased [W/D ratio: 7.54 ± 0.17 vs. 10.69 ± 0.15,MDA (mmol/mg): 2.01 ± 0.30 vs. 2.51 ± 0.25, NO (μmol/L): 3.07 ± 0.21 vs. 3.89 ±0.14,MPO (U/g): 1.94 ± 0.09 vs. 2.74 ± 0.20, TNF-α (μg/L): 201.80 ± 0.27 vs. 297.53 ± 0.34,IL-6 (μg/L): 38.41 ± 0.25 vs. 46.31 ± 0.31,all P<0.05]. RT-PCR showed that the expression of iNOS mRNA in the heparin treatment group was significantly lower than that in the model group (2 (-Δ ΔCt): 3.04 ± 0.18 vs. 4.37 ± 0.15, P < 0.05). Western Blot showed that compared with control group, the protein expressions of iNOS and TGF-β1, and phosphorylation of Smad2 and Smad3 were significantly increased, and the heparin could inhibit the protein expressions compared with model group. Immunohistochemistry showed that positive expressions of iNOS in alveolar epithelial cell and capillary endothelial cell in the heparin treatment group were significantly lower than those in the model group.. Heparin significantly ameliorated the lung injury induced by LPS in rats via the inhibition of nitric oxide synthase expression and the TGF-β/Smad pathway.

Topics: Acute Lung Injury; Animals; Bronchoalveolar Lavage Fluid; Heparin; Interleukin-6; Lipopolysaccharides; Nitric Oxide Synthase; Pulmonary Alveoli; Random Allocation; Rats; Rats, Sprague-Dawley; RNA, Messenger; Signal Transduction; Smad Proteins; Transforming Growth Factor beta; Treatment Outcome

Caveolar domains act as platforms for the organization of molecular complexes involved in signal transduction. Caveolin proteins, the principal structural components of caveolae, have been involved in many cellular processes. Caveolin-1 (Cav-1) and caveolin-2 (Cav-2) are highly expressed in the lung. Cav-1-deficient mice (Cav-1(-/-)) and Cav-2-deficient mice (Cav-2(-/-)) exhibit severe lung dysfunction attributed to a lack of Cav-2 expression. Recently, Cav-1 has been shown to regulate lung fibrosis in different models. Here, we show that Cav-2 is also involved in modulation of the fibrotic response, but through distinct mechanisms. Treatment of wild-type mice with the pulmonary fibrosis-inducer bleomycin reduced the expression of Cav-2 and its phosphorylation at tyrosine 19. Importantly, Cav-2(-/-) mice, but not Cav-1(-/-) mice, were more sensitive to bleomycin-induced lung injury in comparison to wild-type mice. Bleomycin-induced lung injury was characterized by alveolar thickening, increase in cell density, and extracellular matrix deposition. The lung injury observed in bleomycin-treated Cav-2(-/-) mice was not associated with alterations in the TGF-β signaling pathway and/or in the ability to produce collagen. However, apoptosis and proliferation were more prominent in lungs of bleomycin-treated Cav-2(-/-) mice. Since Cav-1(-/-) mice also lack Cav-2 expression and show a different outcome after bleomycin treatment, we conclude that Cav-1 and Cav-2 have distinct roles in bleomycin induced-lung fibrosis, and that the balance of both proteins determines the development of the fibrotic process.

Topics: Acute Lung Injury; Animals; Apoptosis; Bleomycin; Caveolin 1; Caveolin 2; Cell Survival; Collagen; Epithelial Cells; Extracellular Matrix; Gene Expression Regulation; Lung; Male; Mice; Mice, Knockout; Pulmonary Fibrosis; Respiratory Mucosa; Signal Transduction; Transforming Growth Factor beta

Heparin, a potent blood anticoagulant, has been shown to exert a variety of pharmacological activities. The purpose of this study was to investigate whether heparin has a beneficial effect on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats and to further explore the possible underlying mechanisms.. Adult Sprague-Dawley rats were randomly assigned into the control, heparin, LPS, and LPS plus heparin groups. ALI was induced by intratracheal instillation of LPS at a dose of 1 mg/kg. Rats in the LPS plus heparin group were intravenously received 50 U/ kg heparin every 1 h after the induction of ALI.. We found that heparin significantly improved LPS-induced lung pathological changes, inhibited myeloperoxidase (MPO) activity, and reduced malondialdehyde (MDA) level and lung wet/dry weight ratio. Heparin also inhibited the release of tumor necrosis factor (TNF)-α and interleukin (IL)-6, and markedly decreased the expression of inducible nitric oxide synthase (iNOS) in lung tissues and thus prevented nitric oxide (NO) release in response to LPS challenge. Additionally, heparin decreased the expression of transforming growth factor-β1 (TGF-β1), p-Smad 2, and p-Smad 3, which are all important molecules of the TGF-β1/Smad signaling pathway.. Heparin significantly ameliorated the lung injury induced by LPS in rats via the inhibition of nitric oxide synthase expression and the TGF-β/Smad pathway. Heparin may be a potential therapeutic reagent for treating ALI in the future.

Topics: Acute Lung Injury; Animals; Anticoagulants; Heparin; Lipopolysaccharides; Nitric Oxide Synthase; Random Allocation; Rats; Rats, Sprague-Dawley; Signal Transduction; Smad Proteins; Transforming Growth Factor beta; Treatment Outcome

Acute lung injury is a common disorder with a high mortality rate, but previous efforts to develop drugs to treat this disorder have been unsuccessful. In an effort to develop more effective treatments, we have been studying the molecular pathways that regulate the dysfunction of alveolar epithelial cells and endothelial cells that serve as a final common pathway leading to alveolar flooding. Using integrin subunit knockout mice and antibodies we developed by immunizing these mice, we have found important and distinct roles for the αvβ6 integrin on epithelial cells and the αvβ5 integrin on endothelial cells in mediating increases in alveolar permeability in multiple models of acute lung injury. We have also found therapeutic effects of αvβ5 inhibition in two models of septic shock even when the antibody was administered to animals that were obviously ill. These results identify αvβ6 and αvβ5 as promising therapeutic targets for the treatment of acute lung injury and septic shock.

Topics: Acute Lung Injury; Animals; Antigens, Neoplasm; Capillary Permeability; Endothelial Cells; Epithelial Cells; Integrin alphaVbeta3; Integrins; Mice; Pulmonary Alveoli; Receptors, Vitronectin; Shock, Septic; Transforming Growth Factor beta

Hypoxemic respiratory failure of the neonatal organism involves increased acid sphingomyelinase (aSMase) activity and production of ceramide, a second messenger of a pro-inflammatory pathway that promotes increased vascular permeability, surfactant alterations and alveolar epithelial apoptosis. We comparatively assessed the benefits of topical aSMase inhibition by either imipramine (Imi) or phosphatidylinositol-3,5-bisphosphate (PIP2) when administered into the airways together with surfactant (S) for fortification. In this translational study, a triple-hit acute lung injury model was used that entails repeated airway lavage, injurious ventilation and tracheal lipopolysaccharide instillation in newborn piglets subject to mechanical ventilation for 72 hrs. After randomization, we administered an air bolus (control), S, S+Imi, or S+PIP2. Only in the latter two groups we observed significantly improved oxygenation and ventilation, dynamic compliance and pulmonary oedema. S+Imi caused systemic aSMase suppression and ceramide reduction, whereas the S+PIP2 effect remained compartmentalized in the airways because of the molecule's bulky structure. The surfactant surface tensions improved by S+Imi and S+PIP2 interventions, but only to a minor extent by S alone. S+PIP2 inhibited the migration of monocyte-derived macrophages and granulocytes into airways by the reduction of CD14/CD18 expression on cell membranes and the expression of epidermal growth factors (amphiregulin and TGF-β1) and interleukin-6 as pro-fibrotic factors. Finally we observed reduced alveolar epithelial apoptosis, which was most apparent in S+PIP2 lungs. Exogenous surfactant "fortified" by PIP2, a naturally occurring surfactant component, improves lung function by topical suppression of aSMase, providing a potential treatment concept for neonates with hypoxemic respiratory failure.

Topics: Acute Lung Injury; Administration, Topical; Amphiregulin; Animals; Animals, Newborn; Apoptosis; Bronchoalveolar Lavage Fluid; CD18 Antigens; Cell Membrane; Cell Movement; Ceramides; Disease Models, Animal; Female; Glycoproteins; Imipramine; Intercellular Signaling Peptides and Proteins; Interleukin-6; Lipopolysaccharide Receptors; Macrophages; Phosphatidylinositol Phosphates; Pulmonary Surfactants; Respiration, Artificial; Sphingomyelin Phosphodiesterase; Swine; Transforming Growth Factor beta

To hypothesize that bone marrow-derived mononuclear cell (BMDMC) therapy might act differently on lung and distal organs in models of pulmonary or extrapulmonary acute lung injury with similar mechanical compromises. The pathophysiology of acute lung injury differs according to the type of primary insult.. Prospective, randomized, controlled, experimental study.. University research laboratory.. In control animals, sterile saline solution was intratracheally (0.05 mL) or intraperitoneally (0.5 mL) injected. Acute lung injury animals received Escherichia coli lipopolysaccharide intratracheally (40 microg, ALIp) or intraperitoneally (400 microg, ALIexp). Six hours after lipopolysaccharide administration, ALIp and ALIexp animals were further randomized into subgroups receiving saline (0.05 mL) or BMDMC (2 x 10) intravenously. On day 7, BMDMC led to the following: 1) increase in survival rate; 2) reduction in static lung elastance, alveolar collapse, and bronchoalveolar lavage fluid cellularity (higher in ALIexp than ALIp); 3) decrease in collagen fiber content, cell apoptosis in lung, kidney, and liver, levels of interleukin-6, KC (murine interleukin-8 homolog), and interleukin-10 in bronchoalveolar lavage fluid, and messenger RNA expression of insulin-like growth factor, platelet-derived growth factor, and transforming growth factor-beta in both groups, as well as repair of basement membrane, epithelium and endothelium, regardless of acute lung injury etiology; 4) increase in vascular endothelial growth factor levels in bronchoalveolar lavage fluid and messenger RNA expression in lung tissue in both acute lung injury groups; and 5) increase in number of green fluorescent protein-positive cells in lung, kidney, and liver in ALIexp.. BMDMC therapy was effective at modulating the inflammatory and fibrogenic processes in both acute lung injury models; however, survival and lung mechanics and histology improved more in ALIexp. These changes may be attributed to paracrine effects balancing pro- and anti-inflammatory cytokines and growth factors, because a small degree of pulmonary BMDMC engraftment was observed.

Topics: Acute Lung Injury; Animals; Apoptosis; Bone Marrow Transplantation; Bronchoalveolar Lavage Fluid; Caspase 3; Cytokines; Disease Models, Animal; Escherichia coli; Female; Leukocytes, Mononuclear; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Confocal; Microscopy, Electron; Platelet-Derived Growth Factor; Random Allocation; Reference Values; Respiratory Mechanics; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Survival Rate; Transforming Growth Factor beta

Peroxisome proliferator-activated receptor-gamma (PPARgamma) ligands have been shown to possess potent anti-inflammatory actions. Idiopathic interstitial pneumonia is defined as a specific form of chronic fibrosing lung disease characterized by progressive fibrosis which leads to deterioration and destruction of the lungs.. To investigate whether the PPARgamma ligand pioglitazone (PGZ) inhibited bleomycin (BLM)-induced acute lung injury and subsequent fibrosis.. BLM was administered intratracheally to Wistar rats which were then treated with PGZ. Rat alveolar macrophages were stimulated with BLM for 6 h with or without PGZ pretreatment for 18 h. MRC-5 cells (human lung fibroblasts) were treated with PGZ for 18 h. After the treatment, the cells were stimulated with transforming growth factor- beta (TGF-beta) for 6 h.. PGZ inhibited BLM-induced acute lung injury and subsequent lung fibrosis when it was administered from day -7. PGZ treatment suppressed the accumulation of inflammatory cells in lungs and the concentration of tumor necrosis factor-alpha (TNF-alpha) in bronchoalveolar lavage fluid on day 3. PGZ also inhibited BLM-induced TNF-alpha production in alveolar macrophages. Furthermore, PGZ inhibited fibrotic changes and an increase in hydroxyproline content in lungs after instillation of BLM, even when PGZ was administered in the period from day 7 to day 28. Northern blot analyses revealed that PGZ inhibited TGF-beta-induced procollagen I and connective tissue growth factor (CTGF) expression in MRC-5 cells.. These results suggest that activation of PPARgamma ameliorates BLM-induced acute inflammatory responses and fibrotic changes at least partly through suppression of TNF-alpha, procollagen I and CTGF expression. Beneficial effects of this PPARgamma ligand on inflammatory and fibrotic processes open new perspectives for a potential role of PPARgamma as a molecular target in fibroproliferative lung diseases.

Topics: Acute Lung Injury; Animals; Bleomycin; Cells, Cultured; Collagen Type I; Connective Tissue Growth Factor; Fibroblasts; Fibrosis; Humans; Hypoglycemic Agents; Lung; Macrophages, Alveolar; Male; Pioglitazone; PPAR gamma; Rats; Rats, Wistar; Thiazolidinediones; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Despite tremendous technological and therapeutic advances, bronchopulmonary dysplasia (BPD) remains a leading cause of respiratory morbidity in very low birth weight infants, and there are no effective preventive and/or therapeutic options. We have previously reported that hyperoxia-induced neonatal rat lung injury might be prevented by rosiglitazone (RGZ). Here, we characterize 1) perturbations in wingless/Int (Wnt) and transforming growth factor (TGF)-beta signaling, and 2) structural aberrations in lung morphology following 7-day continuous in vivo hyperoxia exposure to neonatal rats. We also tested whether treatment of neonatal pups with RGZ, concomitant to hyperoxia, could prevent such aberrations. Our study revealed that hyperoxia caused significant upregulation of Wnt signaling protein markers lymphoid enhancer factor 1 (Lef-1) and beta-catenin and TGF-beta pathway transducers phosphorylated Smad3 and Smad7 proteins in whole rat lung extracts. These changes were also accompanied by upregulation of myogenic marker proteins alpha-smooth muscle actin (alpha-SMA) and calponin but significant downregulation of the lipogenic marker peroxisome proliferator-activated receptor-gamma (PPARgamma) expression. These molecular perturbations were associated with reduction in alveolar septal thickness, radial alveolar count, and larger alveoli in the hyperoxia-exposed lung. These hyperoxia-induced molecular and morphological changes were prevented by systemic administration of RGZ, with lung sections appearing near normal. This is the first evidence that in vivo hyperoxia induces activation of both Wnt and TGF-beta signal transduction pathways in lung and of its near complete prevention by RGZ. Hyperoxia-induced arrest in alveolar development, a hallmark of BPD, along with these molecular changes strongly implicates these proteins in hyperoxia-induced lung injury. Administration of PPARgamma agonists may thus be a potential strategy to attenuate hyperoxia-induced lung injury and subsequent BPD.

Topics: Actins; Acute Lung Injury; Age Factors; Animals; Animals, Newborn; beta Catenin; Calcium-Binding Proteins; Calponins; Cells, Cultured; Fibroblasts; Hyperoxia; Hypoglycemic Agents; Lac Operon; Lymphoid Enhancer-Binding Factor 1; Mice; Mice, Transgenic; Microfilament Proteins; PPAR gamma; Pulmonary Alveoli; Rats; Rats, Sprague-Dawley; Rosiglitazone; Signal Transduction; Thiazolidinediones; Transforming Growth Factor beta; Wnt Proteins

Topics: Acute Lung Injury; Animals; Biomarkers; Bronchoalveolar Lavage Fluid; Cohort Studies; Disease Models, Animal; Down-Regulation; Fibroblast Growth Factor 7; Forecasting; Gene Expression Regulation; Humans; Prognosis; RNA, Messenger; Sensitivity and Specificity; Survival Analysis; Transforming Growth Factor beta