Total Protein Concentration In Bronchoalveolar Lavage Fluid Research Articles

Therapeutic Effects of (+)-Afzelechin on Particulate Matter-Induced Pulmonary Injury.

Particulate matter (PM) constitutes a hazardous blend of organic and inorganic particles that poses health risks. Inhalation of fine airborne PM with a diameter of ≤ 2.5 μm (PM2.5) can lead to significant lung impairments. (+)-afzelechin (AZC), a natural compound sourced from Bergenia ligulata, boasts a range of attributes, including antioxidant, antimicrobial, anticancer, and cardiovascular effects. However, knowledge about the therapeutic potential of AZC for patients with PM2.5-induced lung injuries remains limited. Thus, in this study, we investigated the protective attributes of AZC against lung damage caused by PM2.5 exposure. AZC was administered to the mice 30 min after intratracheal instillation of PM2.5. Various parameters, such as changes in lung tissue wet/dry (W/D) weight ratio, total protein/total cell ratio, lymphocyte counts, levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF), vascular permeability, and histology, were evaluated in mice exposed to PM2.5. Data demonstrated that AZC mitigated lung damage, reduced W/D weight ratio, and curbed hyperpermeability induced by PM2.5 exposure. Furthermore, AZC effectively lowered plasma levels of inflammatory cytokines produced by PM2.5 exposure. It reduced the total protein concentration in BALF and successfully alleviated PM2.5-induced lymphocytosis. Additionally, AZC substantially diminished the expression levels of Toll-like receptors 4 (TLR4), MyD88, and autophagy-related proteins LC3 II and Beclin 1. In contrast, it elevated the protein phosphorylation of the mammalian target of rapamycin (mTOR). Consequently, the anti-inflammatory attribute of AZC positions it as a promising therapeutic agent for mitigating PM2.5-induced lung injuries by modulating the TLR4-MyD88 and mTOR-autophagy pathways.

Curdione ameliorates sepsis-induced lung injury by inhibiting platelet-mediated neutrophil extracellular trap formation

Sepsis-associated acute lung injury remains to be a major cause of morbidity and mortality worldwide, and there is a lack of effective therapeutic drugs. Curdione, an activeingredient of Curcuma zedoary, a traditional Chinese medicine (TCM), possesses a variety of pharmacological actions, such as anti-inflammatory, antioxidant and inhibition of platelet aggregation. However, whether curdione protects against sepsis-induced lung injury is still undetermined. In this study, we investigated the effects of curdione on sepsis-induced lung injury. Cecal ligation and puncture (CLP) surgery was performed in mice to establish a model of sepsis. Twenty-four hours after CLP, bronchoalveolar lavage fluid (BALF) and lung tissue samples were harvested for investigation. The protective effects of curdione on acute lung injury and potential mechanisms were explored by detecting pathological sections, exudative proteins, oxidative responses, inflammatory factors, platelet activation, neutrophil infiltration, and neutrophil extracellular trap (NET) formation in the lung and were further verified in vitro. We showed that treatment with curdione clearly relieved histopathological changes, reduced inflammatory cytokine elevation and total protein concentrations in BALF, and decreased oxidative stress responses in lung tissues. In addition, curdione inhibited platelet activation, further blocking the interaction between platelets and neutrophils. Finally, neutrophil infiltration and NET formation was also reduced in mice treated with curdione. In conclusion, curdione alleviates sepsis-induced lung injury by inhibiting platelet-mediated neutrophil recruitment, infiltration, and NET formation as well as its anti-inflammatory and antioxidant properties. Curdione has great therapeutic potential in sepsis.

Irbesartan eases lipopolysaccharide-induced lung injury In Vitro and In Vivo.

Acute lung injury (ALI) is classified as a devastating pulmonary disorder contributing to significant incidence and fatality rate. Irbesartan (IRB) is an angiotensin II receptor blocker that has been proposed to protect against oleic acid-induced ALI. To this end, the current study is concentrated on ascertaining the role of IRB in ALI and figuring out the probable action mechanism. First, cell counting kit-8 (CCK-8) appraised the viability of human pulmonary microvascular endothelial cells (HPMVECs) exposed to ascending concentrations of IRB. HPMVEC injury model and a mouse model of ALI induced by lipopolysaccharide (LPS) were pretreated by IRB. In vitro, cell viability was estimated by CCK-8 assay, and lactate dehydrogenase (LDH) release was tested by LDH assay kit. Enzyme-linked immunosorbent assay (ELISA) and Western blotting estimated the expression levels of inflammatory factors. Fluorescein isothiocyanate-dextran was used to assess HPMVEC permeability. Western blotting examined the expression of adherent and tight junction proteins. In vivo, hematoxylin and eosin staining evaluated lung tissue damage and lung wet/dry (W/D) weight was measured. ELISA analyzed the levels of inflammatory factors in the serum and bronchoalveolar lavage fluid (BALF), and Western blotting examined the expression of inflammatory factors. The total cell, neutrophil, and macrophage numbers in BALF were determined using a cell counter. Lung capillary permeability was assayed by Evans blue albumin and total protein concentration in BALF was measured using bicinchoninic acid method. Immunofluorescence assay and Western blotting examined the expression of adherent and tight junction proteins in lung tissues. It was observed that IRB dose-dependently enhanced the viability while reduced LDH release, inflammatory response as well as permeability in LPS-challenged HPMVECs in vitro. In addition, LPS-stimulated lung tissue damage, pulmonary edema, inflammatory response as well as lung capillary permeability in vivo were all reversed following IRB treatment. Collectively, IRB treatment might elicit protective behaviors against LPS-triggered ALI.

Acute lung inflammation induced by zinc oxide nanoparticles: Evolution and intervention via NRF2 activator

Zinc oxide nanoparticles (ZnONPs) are widely used worldwide. Human inhalation exposure to ZnONPs induces acute lung inflammation (ALI); however, the characteristics and therapeutic targets of ALI are unclear. In this study, female C57BL/6J mice were subjected to a single intratracheal instillation of 20 μg of ZnONPs. Increased lung malondialdehyde levels and decreased total antioxidant capacity at 6 h, as well as increased lactate dehydrogenase levels in bronchoalveolar lavage fluid (BALF) at 1 day (d) post treatment were observed. A significant inflammatory response was observed at 3 d and 7 d, as evidenced by increased leukocyte numbers and total protein concentration in BALF, and histological abnormalities. Pulmonary NRF2 signaling was significantly activated at 3 d post treatment. To investigate a protective role of NRF2 activator against ZnONP-induced ALI, the mice were intraperitoneally injected with 2-cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) (2 mg/kg) 1 d before and 1 d after ZnONPs treatment. CDDO-Im significantly decreased leukocyte numbers and total protein concentration in BALF and pulmonary inflammatory gene expression, and ameliorated histopathological abnormalities induced by ZnONPs. Collectively, the present study indicates that ZnONPs exposure leads to oxidative stress, cell injury and inflammation in the lung successively. Moreover, the NRF2 activator protects against ZnONPs-induced ALI.

Long-term cigarette smoke exposure dysregulates pulmonary T cell response and IFN-\u03b3 protection to influenza virus in mouse

BackgroundInfluenza is a highly contagious, acute, febrile respiratory infection caused by a negative-sense, single-stranded RNA virus, which belongs in the Orthomyxoviridae family. Cigarette smoke (CS) exposure worsens influenza infection in terms of frequency and severity in both human and animal models.MethodsC57BL/6 mice with or without CS exposure for 6 weeks were inoculated intranasally with a single, non-lethal dose of the influenza A virus (IAV) A/Puerto Rico/8/1934 (PR8) strain. At 7 and 10 days after infection, lung and mediastinal lymph nodes (MLN) cells were collected to determine the numbers of total CD4 + and CD8 + T cells, and IAV-specific CD4 + and CD8 + T cells, using flow cytometry. Bronchoalveolar lavage fluid (BALF) was also collected to determine IFN-γ levels and total protein concentration.ResultsAlthough long-term CS exposure suppressed early pulmonary IAV-antigen specific CD8 + and CD4 + T cell numbers and IFN-γ production in response to IAV infection on day 7 post-infection, CS enhanced numbers of these cells and IFN-γ production on day 10. The changes of total protein concentration in BALF are consistent with the changes in the IFN-γ amounts between day 7 and 10, which suggested that excessive IFN-γ impaired barrier function and caused lung injury at the later stage of infection.ConclusionsOur results demonstrated that prior CS exposure caused a biphasic T cell and IFN-γ response to subsequent infection with influenza in the lung. Specifically, the number of IAV antigen-specific T cells on day 10 was greatly increased by CS exposure even though CS decreased the number of the same group of cells on day 7. The result suggested that CS affected the kinetics of the T cell response to IAV, which was suppressed at an early stage and exaggerated at a later stage. This study is the first to describe the different effect of long-term CS on T cell responses to IAV at early and late stages of infection in vivo.

Mibefradil and Flunarizine, Two T-Type Calcium Channel Inhibitors, Protect Mice against Lipopolysaccharide-Induced Acute Lung Injury.

Recent studies have illuminated that blocking Ca2+ influx into effector cells is an attractive therapeutic strategy for lung injury. We hypothesize that T-type calcium channel may be a potential therapeutic target for acute lung injury (ALI). In this study, the pharmacological activity of mibefradil (a classical T-type calcium channel inhibitor) was assessed in a mouse model of lipopolysaccharide- (LPS-) induced ALI. In LPS challenged mice, mibefradil (20 and 40 mg/kg) dramatically decreased the total cell number, as well as the productions of TNF-α and IL-6 in bronchoalveolar lavage fluid (BALF). Mibefradil also suppressed total protein concentration in BALF, attenuated Evans blue extravasation, MPO activity, and NF-κB activation in lung tissue. Furthermore, flunarizine, a widely prescripted antimigraine agent with potent inhibition on T-type channel, was also found to protect mice against lung injury. These data demonstrated that T-type calcium channel inhibitors may be beneficial for treating acute lung injury. The important role of T-type calcium channel in the acute lung injury is encouraged to be further investigated.

Human Placental Hematopoietic Stem Cell Derived Natural Killer Cells (CYNK-001) Mediate Protection Against Influenza A Viral Infection

Background: Influenza A virus (IAV) infections are associated with a high healthcare burden around the world and there is an urgent need to develop more effective therapies. Natural killer (NK) cells provide the first line of innate defense against IAV by killing infected epithelial cells, by producing antiviral cytokines and affecting adaptive immunity. Preclinical studies have demonstrated that NK cells play a pivotal role in reducing IAV-induced pulmonary infection; however, little is known about the therapeutic potential of adoptively transferred NK cells for IAV infections. Celularity Inc. is developing human placental hematopoietic stem cell-derived allogeneic, off-the-shelf NK cell therapy (CYNK-001) for the treatment of viral infections, including coronavirus disease of 2019. Here, we report the evaluation of antiviral activities of CYNK-001 against IAV infection.Methods:In vitro antiviral activities of CYNK-001 were evaluated using human alveolar epithelial cell line A549, infected with IAV strain A/PR/8/34 (H1N1) at variable multiplicity of infection (MOI). The expression of ligands for NK cell receptors was analyzed on infected A549 cells using Fc-coupled recombinant proteins. CYNK-001 was added to A549 cells 16 hours post infection. CYNK-001 degranulation was measured after 4 hours of coculture, and CYNK-001 cytotoxicity against IAV-infected A549 was measured real-time using impedance-based xCELLigence platform. In vivo antiviral and immunomodulatory activities of CYNK-001 were assessed in A/PR/8/34 (H1N1)-induced severe acute lung injury mouse model. Mice were intranasally infected with 2500 PFU IAV. PBS or 1 x 107 CYNK-001 cells were intravenously administered twice at 1 and 3 days post infection (dpi). At 6 dpi, lungs were collected for the evaluation of viral load by qPCR, lung injury and immune cell profiling by histology. Bronchoalveolar lavage fluid (BALF) was collected at 6 dpi for cytokine analysis by multiplex assays, total protein concentration by ELISA and immune cell profiling by flow cytometry.Results:In vitro, IAV infection corresponded with dose-dependent expression of ligands to NK cell-activating receptors, including NKp44, NKp46 and NKG2D. CYNK-001 cells exhibited increased IFNγ, TNFα and GM-CSF production, and elevated level of degranulation upon coculture with IAV-infected A549 cells. Cytokines in culture supernatant and CD107a expression in CYNK-001 cells were upregulated in a virus dose-dependent manner. Consistent with this finding, CYNK-001 cytotoxicity against IAV-infected A549 cells increased from 35% at 0 MOI to 50%, 60% and 75% at 0.001, 0.01 and 0.1 MOI, respectively. These data indicate that CYNK-001 cells recognize virally infected cells, resulting in specific cytotoxic elimination of the source of infection. In vivo, treatment of IAV-infected mice with CYNK-001 reduced weight loss and increased their likelihood of survival. PBS control group developed a severe disease and 37.5% mortality was observed as early as day 4. In the group treated with CYNK-001, disease onset was delayed by 2 days. qPCR analysis of viral RNA showed that CYNK-001-treated mice had lower viral load in the lung than vehicle-treated mice, demonstrating antiviral function of CYNK-001 in vivo. CYNK-001-treated mice had reduced lung injury as assessed by lower total protein concentration in BALF. Moreover, CYNK-001 reduced BALF murine cytokines and chemokines, including IFNγ (p<0.001), IL-6, TNFα, MCP-1 (p<0.05), CXCL2 and CXCL9. Lastly, immunohistochemical analysis of the lung showed that CYNK-001-treated mice had an altered immune response to IAV with higher number of CD68+ macrophages and CD8+ T cells at 6 dpi.Conclusions: Our in vitro and in vivo data show the promising antiviral activities of CYNK-001 against IAV infection. In a severe IAV infection mouse model, CYNK-001 treatment demonstrates lower mortality rate, lower weight loss, lower lung viral load and reduced lung injury along with reduced inflammation. These results support our hypothesis that the adoptive transfer of CYNK-001 could reduce the burden of viral infection through the elimination of infected epithelial cells, coordinate a more effective immune response, and result in a clinical benefit in patients with severe viral infection.DisclosuresHe:Celularity Inc.: Current Employment. Mahlakõiv:Celularity Inc.: Current Employment. Gleason:Celularity Inc.: Current Employment, Current equity holder in private company. Van Der Touw:Celularity Inc.: Current Employment. Kang:Celularity Inc.: Current Employment. Hariri:Celularity Inc.: Current Employment, Current equity holder in private company. Zhang:Celularity Inc.: Current Employment, Current equity holder in private company.

Vaspin protects against lipopolysaccharide-induced acute respiratory distress syndrome in mice by inhibiting inflammation and protecting vascular endothelium via PI3K/Akt signal pathway

To investigate the effects of Vaspin on lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) in mice and explore the possible mechanism. Forty male C57B/L6 mice were randomized equally into control group, LPS group, Vaspin group and wortmannin group with corresponding treatments. The pathological changes of the lung tissues were evaluated by HE staining, and the severity of pulmonary edema was measured according to the wet/dry ratio (W/D) of the lung tissue. The lung permeability was evaluated by detecting total protein concentrations in the bronchoalveolar lavage fluid (BALF) using bicinchoninic acid (BCA) assay. Myeloperoxidase (MPO) activity in the lung tissue was detected using a MPO assay kit, and the levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the lungs were measured using ELISA. Immunohistochemical staining was performed to detect the expression of vascular cell adhesion molecule-1 (VCAM-1) and Western blotting was used to detect the protein expressions of cleaved caspase-3 and p-Akt in the lung tissues. Compared with the control group, the mice in LPS group displayed typical ARDS pathological changes in the lungs with significantly increased W/D, total protein concentrations in BALF, lung MPO activity, levels of IL-1β and TNF-α, and pulmonary expressions of VCAM-1 and cleaved caspase-3 (P<0.05) but decreased expression of p-Akt (P<0.05). These changes induced by LPS were significantly alleviated by the administration of Vaspin (P<0.05). The protective effects of Vaspin against ARDS were obviously attenuated by the PI3K inhibitor wortmannin (P<0.05). Vaspin protects against LPS-induced ARDS in mice possibly by inhibiting inflammation and protecting vascular endothelium through upregulation of the PI3K/Akt signal pathway.

Effect of therapeutic hypercapnia preconditioning on lung ischemia-reperfusion injury in rats

Objective To evaluate the effect of therapeutic hypercapnia preconditioning on lung ischemia-reperfusion (I/R) injury in rats. Methods Forty healthy adult Sprague-Dawley rats of either sex, aged 2 months, weighing 250-300 g, were divided into 5 groups (n=8 each) using a random number table: sham operation group (group S), group I/R and preconditioning with therapeutic hypercapnia of different level groups (group THP1-3). Lung I/R injury was induced by clamping the left hilum of lung for 45 min followed by 120 min of reperfusion.In THP1-3 groups, the respiratory parameters were adjusted at 5 min of stability after isolating the left hilum of lung to make PETCO2 reach 55-65, 65-75 and 75-85 mmHg respetively and maintained at this level for 5 min, normal ventilation was then used to make PETCO2 restore the normal level, continuously repeating for 3 circles, and then the left hilum of lung was blocked for 45 min followed by 120 min of reperfusion.The bronchoalveolar lavage fluid (BALF) was collected at the end of reperfusion for determination of the total protein (TP) concentration using Coomassie brilliant blue staining.Lung tissues were obtained at the end of reperfusion for examination of pathological changes after haematoxylin and eosin staining (under a light microscope) and for determination of wet/dry weight ratio (W/D ratio), malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, interleukin-8 (IL-8) and IL-10 contents (by enzyme-linked immunosorbent assay), tumor necrosis factor-alpha (TNF-α) expression (by immunohistochemistry) and expression of TNF-α mRNA (by real-time polymerase chain reaction). Results Compared with group S, the TP concentration in BALF, W/D ratio and contents of MDA, IL-8 and IL-10 in lung tissues were significantly increased, the SOD activity was decreased, the expression of TNF-α mRNA was up-regulated (P 0.05), the staining range and intensity of TNF-α were decreased, and the pathological changes of lung tissues were significantly attenuated in THP1-3 groups. Conclusion Therapeutic hypercapnia preconditioning can reduce lung I/R injury in rats, and the mechanism is related to inhibiting inflammatory responses and oxidative stress responses. Key words: Hypercapnia; Reperfusion injury; Lung; Preconditioning

Ethyl pyruvate reduces acute lung damage following trauma and hemorrhagic shock via inhibition of NF-κB and HMGB1

ObjectiveAfter blunt thoracic trauma (TxT) and hemorrhagic shock with resuscitation (H/R) intense local inflammatory response and cell loss frequently impair the pulmonary function. Ethyl pyruvate (EP) has been reported to improve the pathophysiologic derangements in models of acute inflammation. Here, we studied the effects of EP on inflammation and lung damage after TxT+H/R. MethodsTwenty four female Lewis rats (180–240g) were randomly divided into 3 groups: two groups underwent TxT followed by hemorrhagic shock (35±3mmHg) for 60min and resuscitation with either Ringers-Lactat (RL) alone or RL supplemented with EP (EP, 50mg/kg). Sham operated animals underwent surgical procedures. Two hours later bronchoalveolar lavage fluid (BAL), lung tissue and blood were collected for analyses. ResultsEP significantly improved pO2 levels compared to RL after TxT+H/R. TxT+H/R induced elevated levels of lactate dehydrogenase, total protein concentration in BAL and lung damage as evidenced by lung histology; these effects were significantly reduced by EP. Local inflammatory markers, lung TNF-alpha protein levels and infiltration with polymorphonuclear leukocytes (PMNL) significantly decreased in EP vs. RL group after TxT+H/R. Indicators of apoptosis as reduced BCL-2 and increased FAS gene expression after TxT+H/R were significantly increased or decreased, respectively, by EP after TxT+H/R. EP reduced TxT+H/R-induced p65 phosphorylation, which was concomitant with reduced HMGB1 levels in lung sections. ConclusionsTaken together, TxT+H/R induced strong inflammatory response and apoptotic changes as well as lung injury which were markedly diminished by EP. Our results suggest that this might be mediated via NF-κB and/or HMGB1 dependent mechanism.

Soluble Epoxide Hydrolase Inhibitor Attenuates Lipopolysaccharide-Induced Acute Lung Injury and Improves Survival in Mice.

Acute lung injury (ALI) is characterized by rapid alveolar injury, vascular leakage, lung inflammation, neutrophil accumulation, and induced cytokines production leading to lung edema. The mortality rate of patients suffering from ALI remains high. Epoxyeicosatrienoic acids (EETs) are cytochrome P450-dependent derivatives of polyunsaturated fatty acid with antihypertensive, profibrinolytic, and anti-inflammatory functions. EETs are rapidly hydrated by soluble epoxide hydrolase (sEH) to their less potent diols. The aim of this study was to investigate the role of sEH inhibitor trifluoromethoxyphenyl propionylpiperidin urea (TPPU) and EETs in lipopolysaccharide (LPS)-induced ALI of mice. Our studies revealed that inhibition of sEH with TPPU attenuated the morphological changes in mice, decreased the neutrophil infiltration to the lung, pro-inflammatory cytokine levels (IL-1β and TNF-α) in serum and bronchoalveolar lavage fluid (BALF), and alveolar capillary leakage (lung wet/dry ratio and total protein concentration in BALF). TPPU improved the survival rate of LPS-induced ALI. In addition, in vitro experiments revealed that both TPPU and EETs (11,12-EET and 14,15-EET) suppressed the expression of IL-1β and TNF-α, and LDH release in RAW264.7 cells. These results indicate that EETs play a role in dampening LPS-induced acute lung inflammation, and suggest that sEH could be a valuable candidate for the treatment of ALI.

Pseudomonas aeruginosa Ventilator-Associated Pneumonia Induces Lung Injury through TNF-α/c-Jun NH2-Terminal Kinase Pathways.

Ventilator-associated pneumonia (VAP) is a common nosocomial infection among intensive care unit (ICU) patients. Pseudomonas aeruginosa (PA) is the most common multidrug-resistant Gram-negative pathogen and VAP caused by PA carries a high rate of morbidity and mortality. This study examined the molecular mechanism of PA VAP-induced lung injury. C57BL/6 wild-type (WT) mice and JNK1 knockout (JNK1-/-) mice received mechanical ventilation (MV) for 3 h at 2 days after receiving nasal instillation of PA. The WT and JNK1-/- mice also received MV after the induction of lung injury by instillation of supernatants from PA-stimulated alveolar macrophages (AMs). AMs isolated from WT, IκB-kinase (IKK)βΔMye (IKKβ was selectively deleted in macrophages), and JNK1-/- mice were ex vivo stimulated with live PA and supernatants were collected for cytokine assay. Intranasal instillation of 106 PA enhanced MV-induced NF-κB DNA binding activity in the lungs and nitrite levels in BALF. MV after PA instillation significantly increased the expression of ICAM and VCAM in the lungs and TNF-α, IL-1β, and IL-6 levels in bronchoalveolar lavage fluid (BALF) of WT mice, but not in JNK1-/- mice. MV after supernatant instillation induced more total protein concentration in BALF and neutrophil sequestration in the lungs in WT mice than JNK1-/- mice and cytokine assay of supernatants indicated that TNF-α is a critical regulator of PA VAP-induced lung injury. Ex vivo PA stimulation induced TNF-α production by AMs from WT as well as JNK1-/- mice but not IKKβΔMye mice. In summary, PA colonization plays an important role in PA VAP-induced lung injury through the induction of JNK1-mediated inflammation. These results suggest that the pathogenesis mechanism of PA VAP involves production of TNF-α through activation of IKK/NF-κB pathways in AMs and JNK signaling pathway in the lungs.

Identification of distinct genes associated with seawater aspiration‑induced acute lung injury by gene expression profile analysis.

Seawater aspiration-induced acute lung injury (ALI) is a syndrome associated with a high mortality rate, which is characterized by severe hypoxemia, pulmonary edema and inflammation. The present study is the first, to the best of our knowledge, to analyze gene expression profiles from a rat model of seawater aspiration-induced ALI. Adult male Sprague-Dawley rats were instilled with seawater (4 ml/kg) in the seawater aspiration-induced ALI group (S group) or with distilled water (4 ml/kg) in the distilled water negative control group (D group). In the blank control group (C group) the rats' tracheae were exposed without instillation. Subsequently, lung samples were examined by histopathology; total protein concentration was detected in bronchoalveolar lavage fluid (BALF); lung wet/dry weight ratios were determined; and transcript expression was detected by gene sequencing analysis. The results demonstrated that histopathological alterations, pulmonary edema and total protein concentrations in BALF were increased in the S group compared with in the D group. Analysis of differential gene expression identified up and downregulated genes in the S group compared with in the D and C groups. A gene ontology analysis of the differential gene expression revealed enrichment of genes in the functional pathways associated with neutrophil chemotaxis, immune and defense responses, and cytokine activity. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the cytokine-cytokine receptor interaction pathway was one of the most important pathways involved in seawater aspiration-induced ALI. In conclusion, activation of the cytokine-cytokine receptor interaction pathway may have an essential role in the progression of seawater aspiration-induced ALI, and the downregulation of tumor necrosis factor superfamily member 10 may enhance inflammation. Furthermore, IL-6 may be considered a biomarker in seawater aspiration-induced ALI.

Effects of penehyclidine hydrochloride pretreatment on expression of β-arrestin-1 during sepsis-induced acute lung injury in mice

Objective To investigate the effects of penehyclidine hydrochloride (PHCD) pretreatment on β-arrestin-1 expression during sepsis-induced acute lung injury in mice.Methods Thirty female Kunming mice,weighing 18-20 g,were randomly divided into 3 groups (n =10 each):sham operation group (S group),sepsis group (CLP group) and PHCD group.Sepsis was induced by cecal ligation and puncture (CLP).In PHCD group,PHCD 0.45 mg/kg was injected intraperitoneally 1 h before CLP.The equal volume of normal saline was given instead in groups S and CLP.The mice were sacrificed at 12 h after CLP,bronchoalveolar lavage fluid (BALF) was collected for measurement of the total protein concentration,and the lungs were removed for determination of wet/dry lung weight ratio and expression of myosin light chain kinase (MLCK),vascular endothelial cadherin (VE-cad-herin) and β-arrestin-1 in lung tissues.The pathological changes of the lung were scored.Results Compared with group S,the lung injury score,wet/dry lung weight ratio and total protein concentration in BALF were significantly increased,MLCK expression was up-regulated and VE-cadherin expression was down-regulated in groups CLP and PHCD,β-arrestin-1 expression was down-regulated in group CLP and β-arrestin-1 expression was up-regulated in group PHCD (P ＜ 0.05 or 0.01).The lung injury score,wet/dry lung weight ratio,total protein concentration in BALF,and MLCK expression were significantly lower,while the expression of VE-cadherin and β-arrestin-1 was higher in PHCD group than in CLP group (P ＜ 0.05 or 0.01).Conclusion PHCD pretreatment can ameliorate acute lung injury through up-regulating β-arrestin-1 expression and reducing microvascular permeability in septic mice. Key words: Cholinergic antagonists ; Arrestins ; ; Respiratory distress syndrome, adult ; Sepsis

Role of neutrophil elastase in lung injury induced by burn–blast combined injury in rats

ObjectiveNeutrophil elastase (NE) takes part in the pathogenesis of acute lung injury. However, its role in lung injury of burn–blast combined injury is unclear. Our objective was to assess the role of NE, and effect of sivelestat, a specific NE inhibitor, in lung injury induced by burn–blast combined injury in rats. MethodsOne hundred and sixty male Sprague-Dawley rats were randomly subjected to burn–blast combined injury (BB) group, burn–blast combined injury plus sivelestat treatment (S) group or control (C) group. Blood gas, protein concentration and NE activity in bronchoalveolar lavage fluid (BALF), pulmonary myeloperoxidase (MPO) activity, serum concentrations of TNF-α and IL-8, etc. were investigated from 0h to 7d post-injury. ResultsIn BB group, PaO2 decreased, while NE activity in BALF, total protein concentration in BALF, pulmonary MPO activity and W/D ratio, serum concentrations of TNF-α and IL-8 increased with neutrophil infiltration, progressive bleeding and pulmonary oedema. Compared with BB group, sivelestat treatment decreased the NE activity and ameliorated the above indexes. ConclusionSivelestat, exerts a protective effect in lung injury after burn–blast combined injury through inhibiting NE activity to decrease pulmonary vascular permeability, neutrophil sequestration, and production of TNF-α and IL-8.

Nitrogen dioxide: no influence on allergic sensitization in an intranasal mouse model with ovalbumin and diesel exhaust particles

The role of traffic-related air pollution in the development of allergic diseases is still unclear. We therefore investigated if NO2, an important constituent of traffic-related air pollution, promotes allergic sensitization to the allergen ovalbumin (OVA). We also examined if NO2 influenced the allergy adjuvant activity of diesel exhaust particles (DEP). For this purpose, mice were exposed intranasally to OVA with or without DEP present, immediately followed by exposure to NO2 (5 or 25 parts per million [ppm]) or room air for 4 h in whole body exposure chambers. Eighteen hours after the last of three exposures, the lungs of half of the animals were lavaged with saline and markers of lung damage and lung inflammation in the bronchoalveolar lavage fluid (BALF) were measured. Three weeks later, after intranasal booster immunizations with OVA, the levels of OVA-specific IgE and IgG2a antibodies in serum were determined. Both NO2 (25 ppm) and DEP gave lung damage, measured as increased total protein concentration in BALF, whereas only NO2 seemed to stimulate release of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α). In contrast, only DEP significantly increased the number of neutrophils. Furthermore, DEP in combination with OVA stimulated the production of serum allergen-specific IgE antibodies. NO2, however, neither increased the production of allergen-specific IgE antibodies, nor influenced the IgE adjuvant activity of DEP. Thus, based on our findings, NO2 seems to be of less importance than combustion particles in the development of allergic diseases after exposure to traffic-related air pollution.

High Tidal Volume Ventilation Is Not Deleterious in Infant Rats Exposed to Severe Hemorrhage

Both high tidal volume (V(T)) ventilation and hemorrhage induce acute lung injury in adult rodents. It is not known whether injurious ventilation augments lung injury in infant rats exposed to severe hemorrhage. Two-week-old rats were allocated for ventilation with VT 7 mL/kg and positive end-expiratory pressure (PEEP) 5 cm H₂O (low V(T)) or V(T) 21 mL/kg and PEEP 1 (high V(T)) for 4 hours. Additional rats were subjected to volume-controlled hemorrhage and delayed saline resuscitation, followed by low V(T) or high V(T) ventilation for 4 hours. Nonventilated control groups were also included. Airway resistance and the coefficient of tissue elastance were derived from respiratory input impedance measurements using the low-frequency forced oscillation technique. Pressure-volume curves were obtained at baseline and at the end of the study. Interleukin-6, macrophage inflammatory protein-2, and tumor necrosis factor alpha were determined in bronchoalveolar lavage fluid (BALF) and serum. In both healthy and hemorrhage-exposed animals, high V(T) resulted in reduced elastance (better lung compliance) and increased transcutaneous oxygen saturation. Interleukin-6 in BALF was greater in ventilated animals when compared with nonventilated controls, but not different among ventilated groups. No significant differences were found for all other inflammatory mediators, total protein concentration in BALF, and histology. High V(T) ventilation with low PEEP improves respiratory system mechanics without causing additional damage to healthy and hemorrhage-exposed infant rats after 4 hours of ventilation. This study highlights the tolerance to high V(T) ventilation in infant rats and underscores the need for age-specific animal models.

Effect of L-arginine on pulmonary surfactant in the rats with LPS-induced acute lung injury

Objectiye To investigate the effect of L-arginine on pulmonary surfactant (PS) in the rats with lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods Forty-eight adult male SD rats weighing 220-270 g were randomly divided into 4 groups:group Ⅰ control (group C);group Ⅱ LPS;group Ⅲ LPS 3 h + L-arginine(group L1);group Ⅳ LPS6 h + L-arginine(group L2). ALI was induced by intravenous (Ⅳ)LPS 5 mg/kg in LPS,L1 and L2 groups. L-arginine 500 mg/kg was given intraperitoneally at 3 or 6 h after LPS administration in group L1 or group L2. The animals were sacrificed at 3 h after L-arginine administration, eight animals were sacrificed at 6 h and 9 h after LPS in group C and group LPS. The lungs were immediately removed for determination of surfactant-protein (SP-A) mRNA expression and broncho-alveolar lavage fluid (BALF). The total phospholipid (TPL) and total protein (TP) concentrations in the BALF were measured. Results SP-A mRNA in the lung tissue and TPL concentration in BALF were significantly decreased while TP concentration in BALF was significantly increased in group LPS, as compared with control groups( P ＜ 0.01 ). L-arginine given at 3 h after LPS administration significantly attenuated the LPS-induced changes while L-arginine given at 6 h after LPS did not. Conclusion L-arginine can protect the lungs from LPS-induced injury by up-regulating PS-expression. Key words: Arginine; Endotoxemia; Respiratory distress syndrome, adult; Pulmonary surfactantassociated proteins

Pulmonary response to methylcyclopentadienyl manganese tricarbonyl treatment in rats: injury and repair evaluation.

Methylcyclopentadienyl manganese tricarbonyl (MMT), an organometallic compound, used as an antiknock additive in fuels, may produce alveolar inflammation and bronchiolar cell injury. The aim of the experimental study on female rats was to determine by morphological examination and sensitive biomarkers, the course of the injury and repair process following a single i.p. injection of 5 mg/kg MMT. The animals were sacrificed 12, 24, 48 hours or 7 days post-exposure (PE). The first biochemical changes 12 h PE showed an increase in GSH-S-transferase (GST) activity in the lung parallel to the earliest observed morphological changes -vacuolation and swollen cytoplasm in type I pneumocytes. Alterations in type I pneumocytes were most prevalent in rat lung 24 h PE. Clara cells with dilated smooth endoplasmic reticulum membranes and cytoplasmic vacuolation could be observed. Compared to the values found for controls, Clara cell protein (CC16) in the bronchoalveolar lavage fluid (BALF) at 24 and 48 h PE decreased by 58% and 55%, respectively. At the same time (at 24 and 48 h), the total protein concentration in BALF increased 5 and 7 times, respectively. A significant rise in hyaluronic acid (HA) level was observed 24 and 48 h PE. Divided type II pneumocyte cells and Clara cells in their mitotic phase were observed in immunocytochemistry (detecting BrdU binding into DNA) 48 h PE. Seven days after MMT administration, fibroblasts, macrophages, collagen and elastin fibres could be seen in the alveolar walls as well as neutrophils, lymphocytes, and alveoli macrophages in the alveolar lumen. We conclude that injury and repair of bronchial epithelium cells, especially of Clara cells and type II pneumocyte cells, play an important part in MMT toxicity, probably depending on the antioxidant status of these cells. The sensitive biomarkers of CC16 and hyaluronic acid in BALF and serum reflect lung injury and indicate the time course of pulmonary damage and repair processes.

Effect of transportation on the composition of bronchoalveolar lavage fluid obtained from horses

Abstract Objective To study the effects of extended transportation on the composition of bronchoalveolar lavage fluid (BALF) obtained from horses. Animals 30 horses (14 males, 16 females; 25 Thoroughbreds and 5 Thoroughbred-Arabian crossbreds; 27 to 30 months old) without a history or clinical signs of respiratory tract disease. Bronchoalveolar lavage was performed on nontransported control horses (groups 1 and 2) and transported horses (group 3). Procedure 20 horses were used to determine the effect of 41 hours of transportation on the composition of BALF (group 3). Bronchoalveolar lavage fluid was analyzed for recovered volume, number and distribution of nucleated cells, total protein and phospholipid concentrations, and phospholipid composition. Results Total number of nucleated cells in BALF from group-3 horses increased by approximately fourfold after transportation. Total protein concentration in BALF from group-3 horses also increased by approximately fivefold after transportation. Total phosphorus concentrations in group-3 horses decreased significantly from time 0 to immediately after transportation. In group-3 horses, the most characteristic change in composition of BALF after transport was a significant decrease in the concentration of phosphatidylglycerol. Conclusion and Clinical Relevance The decrease in phosphatidylglycerol concentration in BALF after transportation indicates a reduction in the quantity of surfactant. This change may reflect either a decreased production of surfactant by alveolar type II epithelial cells or an increased removal of surfactant from the alveolar region. It is likely that extended transportation resulted in a decreased concentration of surfactant in BALF. Such a decrease may reduce the pulmonary defence mechanisms in the alveolar region, possibly resulting in infection. (Am J Vet Res 1997;58:531–534)