Expiratory flow-limitation in mechanically ventilated patients: A risk for ventilator-induced lung injury?

Expiratory flow limitation(EFL), that is the inability of expiratory flow to increase in spite of an increase of the driving pressure, is a common and unrecognized occurrence during mechanical ventilation in a variety of intensive care unit conditions. Recent evidence suggests that the presence of EFL is associated with an increase in mortality, at least in acute respiratory distress syndrome(ARDS) patients, and in pulmonary complications in patients undergoing surgery. EFL is a major cause of intrinsic positive end-expiratory pressure(PEEPi), which in ARDS patients is heterogeneously distributed, with a consequent increase of ventilation/perfusion mismatch and reduction of arterial oxygenation. Airway collapse is frequently concomitant to the presence of EFL.When airways close and reopen during tidal ventilation, abnormally high stresses are generated that can damage the bronchiolar epithelium and uncouple small airways from the alveolar septa, possibly generating the small airways abnormalities detected at autopsy in ARDS. Finally, the high stresses and airway distortion generated downstream the choke points may contribute to parenchymal injury, but this possibility is still unproven. PEEP application can abolish EFL, decrease PEEPi heterogeneity, and limit recruitment/derecruitment.Whether increasing PEEP up to EFL disappearance is a useful criterion for PEEP titration can only be determined by future studies.

Molecular Mechanisms of Ventilator-Induced Lung Injury

Objective：Mechanical ventilation （MV） has long been used as a life-sustaining approach for several decades.However,researchers realized that MV not only brings benefits to patients but also cause lung injury if used improperly,which is termed as ventilator-induced lung injury （VILI）.This review aimed to discuss the pathogenesis of VILI and the underlying molecular mechanisms.Data Sources：This review was based on articles in the PubMed database up to December 2017 using the following keywords：＂ventilator-induced lung injury＂,＂pathogenesis＂,＂mechanism＂,and ＂biotrauma＂.Study Selection：Original articles and reviews pertaining to mechanisms of VILI were included and reviewed.Results：The pathogenesis of VILI was defined gradually,from traditional pathological mechanisms （barotrauma,volutrauma,and atelectrauma） to biotrauma.High airway pressure and transpulmonary pressure or cyclic opening and collapse of alveoli were thought to be the mechanisms of barotraumas,volutrauma,and atelectrauma.In the past two decades,accumulating evidence have addressed the importance of biotrauma during VILI,the molecular mechanism underlying biotrauma included but not limited to proinflammatory cytokines release,reactive oxygen species production,complement activation as well as mechanotransduction.Conclusions：Barotrauma,volutrauma,atelectrauma,and biotrauma contribute to VILI,and the molecular mechanisms are being clarified gradually.More studies are warranted to figure out how to minimize lung injury induced by MV.

Serum and lung endothelin-1 increased in a canine model of ventilator-induced lung injury

Background Nitric oxide （NO） plays an important role in acute lung injury （ALl）, acute respiratory distress syndrome （ARDS）, and in ventilator-induced lung injury （VILI）. A change in the balance of endothelin-1 （ET-1） and NO in the ALI/ARDS can also add to these problems. However, the profile of ET-1 and the balance of ET-1 and NO are still unknown in a VILI model. Methods Models of oleic acid induced ALl were established in dogs; these models were then randomized into three groups undergone different tidal volume （VT） mechanical ventilation, which included a VT6 group （VT equaled to 6 ml/kg body weight, positive end expiratory pressure （PEEP） equaled to 10 cmH20, n=-6）, a VT10 group （VT equaled to 10 ml/kg body weight, PEEP equaled to 10 cmH20, n=-4） and a VT20 group （VT equaled to 20 ml/kg body weight, PEEP equaled to 10 cmH20, n=-6） for 6-hour ventilation. The levels of ET-1 and NO in serum and tissue homogenates of lung were observed throughout the trial. Results PaO2 was increased after mechanical ventilation, but hypercapnia occurred in the VT6 group. The magnitudes of lung injury in the VT20 group were more severe than those in the VT6 group and the VT10 group. Serum levels of ET-1 and NO increased after ALl models were established and slightly decreased after a 6-hour ventilation in both the VT6 group and the VT20 group. The serum ET-1 level in the VT20 group was higher than that in the VT6 group and the VT10 group after the 6-hour ventilation （P 〈0.05） while the serum NO levels were similar in the three groups （all P 〉0.05）. There was no significant difference in serum ratio of ET-1/NO between any two out of three groups （P 〉0.05）, although there was a significant positive relationship between serum ET-1 and serum NO （r=0.80, P 〈0.01）. The levels of ET-1 and NO in the lung were increased after ventilation. The lung ET-1 level in the VT20 group was significantly higher than that in the VT6 group and VT10 group （both P 〈0.05） while there was no significant difference in lung NO levels between two groups （P〉0.05）. In the lung tissue, the ratio of ET-1/NO was significantly higher in the VT20 group than in the VT6 group and VT10 group after the 6-hour ventilation （P 〈0.05） as there was a significant positive relationship between ET-1 and NO in the lung （r=0.54, P 〈0.05）. Conclusions The production of ET-1 and NO was increased in serum and lung tissue in a VILI model. But the ET-1 levels increased much more than the NO levels in the lung, though there was a significant positive relationship between levels of ET-1 and NO. These results showed that there was an interaction between ET-1 and NO in a VILI model and changing the balance of ET-1 and NO levels might contribute to the pathophysiologic process of VILI.

Mesenchymal Stem Cell Attenuates Neutrophil-predominant Inflammation and Acute Lung Injury in an In Vivo Rat Model of Ventilator-induced Lung Injury

Background： Subsequent neutrophil （polymorphonuclear neutrophil [PMN]）-predominant inflammatory response is a predominant feature of ventilator-induced lung injury （VILI）, and mesenchymal stem cell （MSC） can improve mice survival model of endotoxin-induced acute lung injury, reduce lung impairs, and enhance the repair inflammatory in the VILI is still unknown. This study aimed to inflammatory in the mechanical VILI. of VILI. However, whether MSC could attenuate PMN-predominant test whether MSC intervention could attenuate the PMN-predominate Methods： Sprague-Dawley rats were ventilated for 2 hours with large tidal volume （20 mL/kg）. MSCs were given before or after ventilation. The inflammatory chemokines and gas exchange were observed and compared dynamically until 4 hours after ventilation, and pulmonary pathological change and activation of PMN were observed and compared 4 hours after ventilation. Results： Mechanical ventilation （MV） caused significant lung injury reflected by increasing in PMN pulmonary sequestration, inflammatory chemokines （tumor necrosis factor-alpha, interleukin-6 and macrophage inflammatory protein 2） in the bronchoalveolar lavage fluid, and injury score of the lung tissue. These changes were accompanied with excessive PMN activation which reflected by increases in PMN elastase activity, production of radical oxygen series. MSC intervention especially pretreatment attenuated subsequent lung injury, systemic inflammation response and PMN pulmonary sequestration and excessive PMN activation initiated by injurious ventilation. Conclusions： MV causes profound lung injury and PMN-predominate inflammatory responses. The protection effect of MSC in the VILI rat model is related to the suppression of the PMN activation.

Effects of minimal lipopolysaccharide-instilled lungs on ventilator-induced lung injury in rats

Mechanical ventilation （MV） may aggravate lung injury induced by a variety of injuries, including intratracheal hydrochloric acid instillation, intratracheal lipopolysaccharide （LPS） instillation with or without concurrent saline lavage, intravenous LPS, or intravenous oleic acid. However, the mechanism for this detrimental effect of MV is unclear. The purpose of the present study was to determine the effect of MV on lung injury induced by minimal LPS-instillation and on the LPS receptor CD14 in the lung.

Impact of interleukin 6 levels on acute lung injury risk and disease severity in critically ill sepsis patients

BACKGROUND Sepsis is a life-threatening condition characterized by a dysregulation of the host response to infection that can lead to acute lung injury(ALI)and multiple organ dysfunction syndrome(MODS).Interleukin 6(IL-6)is a pro-inflammatory cytokine that plays a crucial role in the pathogenesis of sepsis and its complications.AIM To investigate the relationship among plasma IL-6 levels,risk of ALI,and disease severity in critically ill patients with sepsis.METHODS This prospective and observational study was conducted in the intensive care unit of a tertiary care hospital between January 2021 and December 2022.A total of 83 septic patients were enrolled.Plasma IL-6 levels were measured upon admission using an enzyme-linked immunosorbent assay.The development of ALI and MODS was monitored during hospitalization.Disease severity was evaluated by Acute Physiology and Chronic Health Evaluation II(APACHE II)and Sequential Organ Failure Assessment(SOFA)scores.RESULTS Among the 83 patients with sepsis,38(45.8%)developed ALI and 29(34.9%)developed MODS.Plasma IL-6 levels were significantly higher in patients who developed ALI than in those without ALI(median:125.6 pg/mL vs 48.3 pg/mL;P<0.001).Similarly,patients with MODS had higher IL-6 levels than those without MODS(median:142.9 pg/mL vs 58.7 pg/mL;P<0.001).Plasma IL-6 levels were strongly and positively correlated with APACHE II(r=0.72;P<0.001)and SOFA scores(r=0.68;P<0.001).CONCLUSIONElevated plasma IL-6 levels in critically ill patients with sepsis were associated with an increased risk of ALI andMODS.Higher IL-6 levels were correlated with greater disease severity,as reflected by higher APACHE II andSOFA scores.These findings suggest that IL-6 may serve as a biomarker for predicting the development of ALI anddisease severity in patients with sepsis.

MicroRNA-451 from Human Umbilical Cord-Derived Mesenchymal Stem Cell Exosomes Inhibits Alveolar Macrophage Autophagy via Tuberous Sclerosis Complex 1/Mammalian Target of Rapamycin Pathway to Attenuate Burn-Induced Acute Lung Injury in Rats

Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechanisms by which miR-451 in hUC-MSC-Exos reduces ALI by modulating macrophage autophagy.Methods Exosomes were isolated from hUC-MSCs.Severe burn-induced ALI rat models were treated with hUC-MSC-Exos carrying the miR-451 inhibitor.Hematoxylin-eosin staining evaluated inflammatory injury.Enzyme-linked immunosorbnent assay measured lipopolysaccharide(LPS),tumor necrosis factor-α,and interleukin-1βlevels.qRT-PCR detected miR-451 and tuberous sclerosis complex 1(TSC1)expressions.The regulatory role of miR-451 on TSC1 was determined using a dual-luciferase reporter system.Western blotting determined TSC1 and proteins related to the mammalian target of rapamycin(mTOR)pathway and autophagy.Immunofluorescence analysis was conducted to examine exosomes phagocytosis in alveolar macrophages and autophagy level.Results hUC-MSC-Exos with miR-451 inhibitor reduced burn-induced ALI and promoted macrophage autophagy.MiR-451 could be transferred from hUC-MSCs to alveolar macrophages via exosomes and directly targeted TSC1.Inhibiting miR-451 in hUC-MSC-Exos elevated TSC1 expression and inactivated the mTOR pathway in alveolar macrophages.Silencing TSC1 activated mTOR signaling and inhibited autophagy,while TSC1 knockdown reversed the autophagy from the miR-451 inhibitor-induced.Conclusion miR-451 from hUC-MSC exosomes improves ALI by suppressing alveolar macrophage autophagy through modulation of the TSC1/mTOR pathway,providing a potential therapeutic strategy for ALI.

Mogroside IIE,an in vivo metabolite of sweet agent,alleviates acute lung injury via Pla2g2a-EGFR inhibition

In the face of increasingly serious environmental pollution,the health of human lung tissues is also facing serious threats.Mogroside IIE(M2E)is the main metabolite of sweetening agents mogrosides from the anti-tussive Chinese herbal Siraitia grosvenori.The study elucidated the anti-inflammatory action and molecular mechanism of M2E against acute lung injury(ALI).A lipopolysaccharide(LPS)-induced ALI model was established in mice and MH-S cells were employed to explore the protective mechanism of M2E through the western blotting,co-immunoprecipitation,and quantitative real time-PCR analysis.The results indicated that M2E alleviated LPS-induced lung injury through restraining the activation of secreted phospholipase A2 type IIA(Pla2g2a)-epidermal growth factor receptor(EGFR).The interaction of Pla2g2a and EGFR was identified by co-immunoprecipitation.In addition,M2E protected ALI induced with LPS against inflammatory and damage which were significantly dependent upon the downregulation of AKT and m TOR via the inhibition of Pla2g2a-EGFR.Pla2g2a may represent a potential target for M2E in the improvement of LPS-induced lung injury,which may represent a promising strategy to treat ALI.

Mechanisms and Research Progress of Traditional Chinese Medicine Regulating NF-κB in the Treatment of Acute Lung Injury/Acute Respiratory Distress Syndrome

Acute lung injury(ALI)has multiple causes and can easily progress to acute respiratory distress syndrome(ARDS)if not properly treated.Nuclear factorκB(NF-κB)is a key pathway in the treatment of ALI/ARDS.By exploring the relevance of NF-κB and the pathogenesis of this disease,it was found that this disease was mainly associated with inflammation,dysfunction of the endothelial barrier,oxidative stress,impaired clearance of alveolar fluid,and coagulation disorders.Traditional Chinese medicine(TCM)has the characteristics of multitargeting,multipathway effects,and high safety,which can directly or indirectly affect the treatment of ALI/ARDS.This article summarizes the mechanism and treatment strategies of TCM in recent years through intervention in the NF-κB-related signaling pathways for treating ALI/ARDS.It provides an overview from the perspectives of Chinese herbal monomers,TCM couplet medicines,TCM injections,Chinese herbal compounds,and Chinese herbal preparations,offering insights into the prevention and treatment of ALI/ARDS with TCM.

Research Progress on the Pathogenesis of Acute Lung Injury(ALI)

In this review,the databases searched were PubMed and Web of Science.It is believed that the main causes of acute lung injury(ALI)and acute respiratory distress syndrome(ARDS)are inflammatory response disorders,excessive oxidative stress,cell death,endoplasmic reticulum stress,coagulation dysfunction,and weakened aquaporin function.

Research Progress on the Prevention of Premature Infant Lung Injury and Neonatal Respiratory Support

In the past 40 years,advances in neonatal intensive care unit(NICU)technology have enabled premature infants with lower birth weight and younger gestational age to survive.But with it comes an increase in the incidence of long-term respiratory dysfunction,mainly in the form of bronchopulmonary dysplasia(BPD).Preventing lung injury is crucial for preventing BPD and improving the long-term prognosis of premature infants.Therefore,how to avoid ventilator-associated lung injury has become a focus of clinical and scientific research in premature infants in recent years.This article will elaborate on the susceptibility and pathophysiology of premature infant lung injury,ventilation strategies for preventing lung injury,and new advances in neonatal respiratory support.

Modulating the crosstalk between macrophage and Th17: potential mechanism of natural products on acute lung injury

Sepsis is a life-threatening multiple organ dysfunction syndrome caused by the imbalance of the immune response to infection,featuring complex and variable conditions,and is one of the leading causes of mortality in ICU patients.Lung injury is a common organ damage observed in sepsis patients.Macrophages and Th17 cells,as crucial components of innate and adaptive immunity,play pivotal roles in the development of sepsis-induced acute lung injury(ALI).This review summarizes the alterations and mechanisms of macrophages and Th17 cells in sepsis-induced ALI.By focusing on the“cross-talk”between macrophages and Th17 cells,this review aims to provide a solid theoretical foundation for further exploring the therapeutic targets of traditional Chinese medicine formulas in the treatment of sepsis complicated with ALI,thereby offering insights and guidance for the clinical application of traditional Chinese medicine in managing sepsis-associated ALI.

Effects of dynamic ventilatory factors on ventilatorinduced lung injury in acute respiratory distress syndrome dogs

BACKGROUND： Mechanical ventilation is a double-edged sword to acute respiratory distress syndrome （ARDS） including lung injury, and systemic inflammatory response high tidal volumes are thought to increase mortality. The objective of this study is to evaluate the effects of dynamic ventilatory factors on ventilator induced lung injury in a dog model of ARDS induced by hydrochloric acid instillation under volume controlled ventilation and to investigate the relationship between the dynamic factors and ventilator-induced lung injuries （VILI） and to explore its potential mechanisms.METHODS： Thirty-six healthy dogs were randomly divided into a control group and an experimental group. Subjects in the experimental group were then further divided into four groups by different inspiratory stages of flow. Two mL of alveolar fluid was aspirated for detection of IL-8 and TNF-α. Lung tissue specimens were also extracted for total RNA, IL-8 by western blot and observed under an electronic microscope.RESULTS： IL-8 protein expression was significantly higher in group B than in groups A and D. Although the IL-8 protein expression was decreased in group C compared with group B, the difference was not statistically significant. The TNF-a ray degree of group B was significantly higher than that in the other groups （P〈0.01）, especially in group C （P〉0.05）. The alveolar volume of subjects in group B was significantly smaller, and cavity infiltration and cell autolysis were marked with a significant thicker alveolar septa, disorder of interval structures, and blurring of collagenous and elastic fiber structures. A large number of necrotic debris tissue was observed in group B.CONCLUSION： Mechanical ventilation with a large tidal volume, a high inspiratory flow and a high ventilation frequency can cause significant damage to lung tissue structure. It can significantly increase the expression of TNF-α and IL-8 as well as their mRNA expression. Furthermore, the results of our study showed that small tidal ventilation significantly reduces the release of proinflammatory media. This finding suggests that greater deterioration in lung injury during ARDS is associated with high inspiratory flow and high ventilation rate.

Acute lung injury and ARDS in acute pancreatitis: Mechanisms and potential intervention

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) in acute pancreatitis still represents a substantial problem,with a mortality rate in the range of 30%-40%.The present review evaluates underlying pathophysiological mechanisms in both ALI and ARDS and potential clinical implications.Several mediators and pathophysiological pathways are involved during the different phases of ALI and ARDS.The initial exudative phase is characterized by diffuse alveolar damage,microvascular injury and influx of inflammatory cells.This phase is followed by a fibro-proliferative phase with lung repair,type Ⅱ pneumocyte hypoplasia and proliferation of fibroblasts.Proteases derived from polymorphonuclear neutrophils,various pro-inflammatory mediators,and phospholipases are all involved,among others.Contributing factors that promote pancreatitis-associated ALI may be found in the gut and mesenteric lymphatics.There is a lack of complete understanding of the underlying mechanisms,and by improving our knowledge,novel tools for prevention and intervention may be developed,thus contributing to improved outcome.

Dexmedetomidine Alleviates Pulmonary Edema by Upregulating AQP1 and AQP5 Expression in Rats with Acute Lung Injury Induced by Lipopolysaccharide

This study aims to elucidate the mechanisms by which dexmedetomidine alleviates pulmonary edema in rats with acute lung injury induced by lipopolysaccharide （LPS）. Male Wistar rats were randomly divided into five groups： normal saline control （NS） group, receiving intravenous 0.9% normal saline （5 mL/kg）; LPS group, receiving intravenous LPS （10 mg/kg）; small-dose dexmedetomidine （S） group, treated with a small dose of dexmedetomidine （0.5 μg·kg^-1·h^-1）; medium-dose dexmedetomidine （M） group, treated with a medium dose of dexmedetomidine （2.5 μg·kg^-1·h^-1）; high-dose dexmedetomidine （H） group, treated with a high dose of dexmedetomidine （5μg·kg^-1·h^-1）. The rats were sacrificed 6 h after intravenous injection of LPS or NS, and the hmgs were removed for evaluating histological characteristics and determining the lung wet/dry weight ratio （W/D）. The levels of tumor necrosis factor-alpha （TNF-α） and interleukin-1β （IL-1β） in the lung tissues were assessed by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein expression levels of aquaporin-1 （AQP1） and aquaporin-5 （AQP5） were detected by RT-PCR, immunohistochemistry, and Western blot- ting. The lung tissues from the LPS groups were significantly damaged, which were less pronounced in the H group but not in the small-dose dexmedetomidine group or medium-dose dexmedetomidine group. The W/D and the concentrations of TNF-α and IL-1β in the pulmonary tissues were increased in the LPS group as compared with those in NS group, which were reduced in the H group but not in S group or M group （P〈0.01）. The expression of AQP1 and AQP5 was lower in the LPS group than in the NS group, and significantly increased in the H group but not in the S group or M group （P〈0.01）. Our findings suggest that dexmedetomidine may alleviate pulmonary edema by increasing the expression of AQP-1 and AQP-5.

Circulating miRNAs as biomarkers for severe acute pancreatitis associated with acute lung injury

AIM To identify circulating micro(mi)RNAs as biological markers for prediction of severe acute pancreatitis(SAP) with acute lung injury(ALI).METHODS Twenty-four serum samples were respectively collected and classified as SAP associated with ALI and SAP without ALI, and the mi RNA expression profiles were determined by microarray analysis. These mi RNAs were validated by quantitative reverse transcriptionpolymerase chain reaction, and their putative targets were predicted by the online software Target Scan, mi Randa and Pic Tar database. Gene ontology(GO) and Kyoto encyclopedia of genes and genomes(commonly known as KEGG) were used to predict their possible functions and pathways involved.RESULTS We investigated 287 mi RNAs based on microarray data analysis. Twelve mi RNAs were differentially expressed in the patients with SAP with ALI and those with SAP without ALI. Hsa-mi R-1260 b, 762, 22-3 p, 23 b and 23 a were differently up-regulated and hsa-mi R-550 a*, 324-5 p, 484, 331-3 p, 140-3 p, 342-3 p and 150 were differently down-regulated in patients with SAP with ALI compared to those with SAP without ALI. In addition, 85 putative target genes of the significantly dysregulated mi RNAs were found by Target Scan, mi Randa and Pic Tar. Finally, GO and pathway network analysis showed that they were mainly enriched in signal transduction, metabolic processes, cytoplasm and cell membranes.CONCLUSION This is the first study to identify 12 circulating mi RNAs in patients with SAP with ALI, which may be biomarkers for prediction of ALI after SAP.

N-acetylcysteine inhibits activation of toll-like receptor 2 and 4 gene expression in the liver and lung after partial hepatic ischemia-reperfusion injury in mice

BACKGROUND: Toll-like receptor 2 and 4 (TLR2/4) may play important roles in ischemia-reperfusion (I/R) injury, and N-acetylcysteine (NAC) can prevent the generation of reactive oxygen species (ROS) induced by I/R injury. This study aimed to investigate the changes in TLR2/4 gene expression in the liver and lung after I/R injury with or without NAC pretreatment. METHODS: BALB/c mice were used in a model of partial hepatic I/R injury and randomly assigned to a sham-operated control group (SH), a hepatic ischemia/reperfusion group (I/R) or a NAC pretreated, hepatic I/R group (I/R-NAC). The levels of TNF-alpha in the portal vein and plasma alanine aminotransferase (ALT) were measured at 1 and 3 hours after reperfusion. The lung wet-to-dry ratio was measured, and the expression of TLR2/4 mRNA and protein in the liver and lung were assessed with RT-PCR and Western blotting at the same time points. RESULTS: Compared with the I/R group, the expression of TLR2/4 mRNA and protein in the liver and lung in the I/R-NAC group was decreased at the same time point (P<0.05). The levels of portal vein TNF-a and plasma ALT increased continuously in the l/R group at I and 3 hours of reperfusion compared with the SH group; however, they declined significantly in the group pretreated with NAC (P<0.05). The extent of lung edema was relieved in the I/R-NAC group compared with the I/R group (P<0.05). CONCLUSIONS: TLR2/4 was activated in the liver and lung in the process of partial hepatic I/R injury. NAC inhibited the activation of TLR2/4 and the induction of TNF-alpha resulting from I/R injury via modulating the redox state, thus it may mitigate liver and lung injury following partial hepatic I/R in mice.

Synergistic protection of astragalus polysaccharides and matrine against ulcerative colitis and associated lung injury in rats

BACKGROUND Ulcerative colitis(UC)is a main form of inflammatory bowel disease.Due to complicated etiology and a high rate of recurrence,it is quite essential to elucidate the underlying mechanism of and search for effective therapeutic methods for UC.AIM To investigate the effects of astragalus polysaccharides(APS)combined with matrine on UC and associated lung injury.METHODS UC was induced in rats by colon mucosal tissue sensitization combined with trinitro-benzene-sulfonic acid-ethanol.Then,the effects of the treatments of salazopyrine,APS,matrine,and APS combined with matrine on histopathological changes of lung and colon tissues,disease activity index(DAI),colon mucosal damage index(CMDI),serum endotoxin(ET)level,serum diamine oxidase(DAO)activity,the contents of tumor necrosis factor-αand interleukin-1β,and the activities of myeloperoxidase,superoxide dismutase,and malondialdehyde in lung tissues,as well as the protein expression of zonula occludens(ZO)-1,Occludin,and trefoil factor 3(TFF3)were detected in UC rats.RESULTS The treatments of salazopyrine,APS,matrine,and APS combined with matrine reduced DAI scores and improved histopathological changes of colon and lung tissues,as well as decreased CMDI scores,ET levels,and DAO activities in UC rats.Moreover,in lung tissues,inflammatory response and oxidative stress injury were relieved after the treatments of salazopyrine,APS,matrine,and APS combined with matrine in UC rats.Furthermore,the expression of ZO-1,Occludin,and TFF3 in lung and colon tissues was increased after different treatments in UC rats.Notably,APS combined with matrine exerted a better protective effect against UC and lung injury compared with other treatments.CONCLUSION APS combined with matrine exert a synergistic protective effect against UC and lung injury,which might be associated with regulating TFF3 expression.

Cyclooxygenase-2 plays a central role in the genesis of pancreatitis and associated lung injury

BACKGROUND: The exact mechanism by which cyclooxy- genase-2 (COX-2) promotes inflammation in pancreatitis in obscure. This study was undertaken to investigate the role of COX-2 inhibition in an animal model of pancreati- tis , a disease process characterized by a systemic inflamma- tory response and ensuing neutrophil-mediated lung injury. METHODS: Pancreatitis was induced in 24 Sprague-Daw- ley rats by intraperitoneal injection of 20% L-arginine (500 mg/100 g body weight). The animals were randomized into 3 groups (8 rats in each group); controls and rats with pancreatitis intravenously resuscitated with either normal saline (0.9% NaCl 3 ml/kg) at 24 and 48 hours or COX-2 inhibitor (parecoxib 1 mg/kg). Pancreatic and lung inju- ries were assessed histologically. Lung injury was assessed utilizing wet;dry ratio and myeloperoxidase activity to in- dicate pulmonary neutrophil infiltration. A Western blot was used to determine COX-2 protein expression in pancrea- tic tissue. RESULTS: The animals treated with COX-2 inhibitors dis- played significantly less pancreatic and lung injuries than their normal saline counterparts. Histological pancreatic and lung injury scores were significantly reduced (P <0.05) in the COX-2 treated group. Lung wet: dry ratios were sig- nificantly improved and pulmonary neutrophil infiltration was attenuated in the COX-2 group (P<0.05). Western blot analysis confirmed attenuated COX-2 protein expression. CONCLUSION: This study shows, for the first time in a rat model, that adjuvant COX-2 inhibition significandy attenu- ates the severity of both pancreatitis and its associated sys- temic inflammatory response and end-organ injury.