Protective Mechanism of Cordyceps sinensis Treatment on Acute Kidney Injury-Induced Acute Lung Injury through AMPK/mTOR Signaling Pathway / 中国结合医学杂志

OBJECTIVE@#To investigate protective effect of Cordyceps sinensis (CS) through autophagy-associated adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway in acute kidney injury (AKI)-induced acute lung injury (ALI).@*METHODS@#Forty-eight male Sprague-Dawley rats were divided into 4 groups according to a random number table, including the normal saline (NS)-treated sham group (sham group), NS-treated ischemia reperfusion injury (IRI) group (IRI group), and low- (5 g/kg·d) and high-dose (10 g/kg·d) CS-treated IRI groups (CS1 and CS2 groups), 12 rats in each group. Nephrectomy of the right kidney was performed on the IRI rat model that was subjected to 60 min of left renal pedicle occlusion followed by 12, 24, 48, and 72 h of reperfusion. The wet-to-dry (W/D) ratio of lung, levels of serum creatinine (Scr), blood urea nitrogen (BUN), inflammatory cytokines such as interleukin- β and tumor necrosis factor- α, and biomarkers of oxidative stress such as superoxide dismutase, malonaldehyde (MDA) and myeloperoxidase (MPO), were assayed. Histological examinations were conducted to determine damage of tissues in the kidney and lung. The protein expressions of light chain 3 II/light chain 3 I (LC3-II/LC3-I), uncoordinated-51-like kinase 1 (ULK1), P62, AMPK and mTOR were measured by Western blot and immunohistochemistry, respectively.@*RESULTS@#The renal IRI induced pulmonary injury following AKI, resulting in significant increases in W/D ratio of lung, and the levels of Scr, BUN, inflammatory cytokines, MDA and MPO (P<0.01); all of these were reduced in the CS groups (P<0.05 or P<0.01). Compared with the IRI groups, the expression levels of P62 and mTOR were significantly lower (P<0.05 or P<0.01), while those of LC3-II/LC3-I, ULK1, and AMPK were significantly higher in the CS2 group (P<0.05 or P<0.01).@*CONCLUSION@#CS had a potential in treating lung injury following renal IRI through activation of the autophagy-related AMPK/mTOR signaling pathway in AKI-induced ALI.

Xuebijing alleviates LPS-induced acute lung injury by downregulating pro-inflammatory cytokine production and inhibiting gasdermin-E-mediated pyroptosis of alveolar epithelial cells / 中国天然药物

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is characterized by diffuse alveolar injury primarily caused by an excessive inflammatory response. Regrettably, the lack of effective pharmacotherapy currently available contributes to the high mortality rate in patients with this condition. Xuebijing (XBJ), a traditional Chinese medicine recognized for its potent anti-inflammatory properties, exhibits promise as a potential therapeutic agent for ALI/ARDS. This study aimed to explore the preventive effects of XBJ on ALI and its underlying mechanism. To this end, we established an LPS-induced ALI model and treated ALI mice with XBJ. Our results demonstrated that pre-treatment with XBJ significantly alleviated lung inflammation and increased the survival rate of ALI mice by 37.5%. Moreover, XBJ substantially suppressed the production of TNF-α, IL-6, and IL-1β in the lung tissue. Subsequently, we performed a network pharmacology analysis and identified identified 109 potential target genes of XBJ that were mainly involved in multiple signaling pathways related to programmed cell death and anti-inflammatory responses. Furthermore, we found that XBJ exerted its inhibitory effect on gasdermin-E-mediated pyroptosis of lung cells by suppressing TNF-α production. Therefore, this study not only establishes the preventive efficacy of XBJ in ALI but also reveals its role in protecting alveolar epithelial cells against gasdermin-E-mediated pyroptosis by reducing TNF-α release.

Basic research and clinical innovative treatment in patients with sudden mass phosgene poisoning / 中华危重病急救医学

Phosgene is not only a dangerous asphyxiating chemical warfare agent, but also an important chemical raw material, which is widely used in chemical production. According to statistics, there are more than 1 000 phosgene production enterprises in China, with an annual production volume of more than 3 million tons and hundreds of thousands of employees. Therefore, once the leakage accident occurs during production, storage and transportation, it often causes a large number of casualties. In the past 20 years, phosgene poisoning accidents in China have occurred from time to time, and due to the weak irritation, high density, and high concentration of phosgene at the scene of the accident, it often results in acute high-concentration inhalation of the exposed, triggering acute lung injury (ALI), and is very likely to progress to acute respiratory distress syndrome (ARDS), with a mortality rate up to 40%-50%. In view of the characteristics of sudden, mass, concealed, rapid and highly fatal phosgene, and the mechanism of its toxicity and pathogenicity is still not clear, there is no effective treatment and standardized guidance for the sudden group phosgene poisoning. In order to improve the efficiency of clinical treatment and reduce the mortality, this paper has summarized the pathophysiological mechanism of phosgene poisoning, clinical manifestations, on-site treatment, research progress, and innovative clinical therapies by combining the extensive basic research on phosgene over the years with the abundant experience in the on-site treatment of sudden mass phosgene poisoning. This consensus aims to provide guidance for the clinical rescue and treatment of patients with sudden mass phosgene poisoning, and to improve the level of treatment.

Wedelolactone alleviates hyperoxia-induced acute lung injury by regulating ferroptosis / 中华危重病急救医学

OBJECTIVE@#To study whether wedelolactone can reduce hyperoxia-induced acute lung injury (HALI) by regulating ferroptosis, and provide a basic theoretical basis for the drug treatment of HALI.@*METHODS@#A total of 24 C57BL/6J mice were randomly divided into normal oxygen control group, HALI model group and wedelolactone pretreatment group, with 8 mice in each group. Mice in wedelolactone pretreatment group were treated with wedelolactone 50 mg/kg intraperitoneally for 6 hours, while the other two groups were not given with wedelolactone. After that, the HALI model was established by maintaining the content of carbon dioxide < 0.5% and oxygen > 90% in the molding chamber for 48 hours, and the normal oxygen control group was placed in indoor air. After modeling, the mice were sacrificed and lung tissues were collected. The lung histopathological changes were observed under light microscope and pathological scores were performed to calculate the ratio of lung wet/dry mass (W/D). The levels of tumor necrosis factor-α (TNF-α), interleukins (IL-6, IL-1β), superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) in lung tissues of mice in each group were determined. The protein expression of glutathione peroxidase 4 (GPX4) in lung tissue was detected by Western blotting.@*RESULTS@#Under light microscope, the alveolar structure of HALI model group was destroyed, and a large number of neutrophils infiltrated the alveolar and interstitial lung, and the interstitial lung was thickened. The pathological score of lung injury (score: 0.75±0.02 vs. 0.11±0.01) and the ratio of lung W/D (6.23±0.34 vs. 3.68±0.23) were significantly higher than those in the normal oxygen control group (both P < 0.05). Wedelolactone pretreated mice had clear alveolar cavity and lower neutrophil infiltration and interstitial thickness than HALI group. Pathological scores (score: 0.43±0.02 vs. 0.75±0.02) and W/D ratio (4.56±0.12 vs. 6.23±0.34) were significantly lower than HALI group (both P < 0.05). Compared with the normal oxygen control group, the levels of SOD (kU/g: 26.41±4.25 vs. 78.64±3.95) and GSH (mol/g: 4.51±0.33 vs. 12.53±1.25) in HALI group were significantly decreased, while the levels of MDA (mmol/g: 54.23±4.58 vs. 9.65±1.96), TNF-α (μg/L: 96.32±3.67 vs. 11.65±2.03), IL-6 (ng/L: 163.35±5.89 vs. 20.56±3.63) and IL-1β (μg/L: 72.34±4.64 vs. 15.64±2.47) were significantly increased, and the protein expression of GPX4 (GPX4/β-actin: 0.44±0.02 vs. 1.00±0.09) was significantly decreased (all P < 0.05). Compared with the HALI group, the levels of SOD (kU/g: 53.28±3.69 vs. 26.41±4.25) and GSH (mol/g: 6.73±0.97 vs. 12.53±1.25) were significantly higher in the wedelolactone pretreatment group, and the levels of MDA (mmol/g: 25.36±1.98 vs. 54.23±4.58), TNF-α (μg/L: 40.25±4.13 vs. 96.32±3.67), IL-6 (ng/L: 78.32±4.65 vs. 163.35±5.89), and IL-1β (μg/L: 30.65±3.65 vs. 72.34±4.64) were significantly lower (all P < 0.05), and protein expression of GPX4 was significantly higher (GPX4/β-actin: 0.68±0.04 vs. 0.44±0.02, P < 0.05).@*CONCLUSIONS@#Wedelolactone attenuates HALI injury by regulating ferroptosis.

Shenfu Injection alleviates sepsis-associated lung injury by regulating HIF-1α / 中国中药杂志

Shenfu Injection(SFI) is praised for the high efficacy in the treatment of septic shock. However, the precise role of SFI in the treatment of sepsis-associated lung injury is not fully understood. This study investigated the protective effect of SFI on sepsis-associated lung injury by a clinical trial and an animal experiment focusing on the hypoxia-inducing factor-1α(HIF-1α)-mediated mitochondrial autophagy. For the clinical trial, 70 patients with sepsis-associated lung injury treated in the emergency intensive care unit of the First Affiliated Hospital of Zhengzhou University were included. The levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-α were measured on days 1 and 5 for every patient. Real-time quantitative polymerase chain reaction(RT-qPCR) was performed to determine the mRNA level of hypoxia inducible factor-1α(HIF-1α) in the peripheral blood mononuclear cells(PBMCs). For the animal experiment, 32 SPF-grade male C57BL/6J mice(5-6 weeks old) were randomized into 4 groups: sham group(n=6), SFI+sham group(n=10), SFI+cecal ligation and puncture(CLP) group(n=10), and CLP group(n=6). The body weight, body temperature, wet/dry weight(W/D) ratio of the lung tissue, and the pathological injury score of the lung tissue were recorded for each mouse. RT-qPCR and Western blot were conducted to determine the expression of HIF-1α, mitochondrial DNA(mt-DNA), and autophagy-related proteins in the lung tissue. The results of the clinical trial revealed that the SFI group had lowered levels of inflammatory markers in the blood and alveolar lavage fluid and elevated level of HIF-1α in the PBMCs. The mice in the SFI group showed recovered body temperature and body weight. lowered TNF-α level in the serum, and decreased W/D ratio of the lung tissue. SFI reduced the inflammatory exudation and improved the alveolar integrity in the lung tissue. Moreover, SFI down-regulated the mtDNA expression and up-regulated the protein levels of mitochondrial transcription factor A(mt-TFA), cytochrome c oxidase Ⅳ(COXⅣ), HIF-1α, and autophagy-related proteins in the lung tissue of the model mice. The findings confirmed that SFI could promote mitophagy to improve mitochondrial function by regulating the expression of HIF-1α.

Exploring the treatment of sepsis-associated acute lung injury with Liangge Powder via ERK1/2 and PI3K/AKT pathways: based on network pharmacology and whole animal experimentation / 中华劳动卫生职业病杂志

Objective: To investigate the therapeutic effect and mechanism of Liangge Powder against sepsis-induced acute lung injury (ALI) . Methods: From April to December 2021, the key components of Liangge Powder and its targets against sepsis-induced ALI were analyzed by network pharmacology, and to enrich for relevant signaling pathways. A total of 90 male Sprague-Dawley rats were randomly assigned to sham-operated group, sepsis-induced ALI model group (model group), Liangge Powder low, medium and high dose group, ten rats in the sham-operated group and 20 rats in each of the remaining four groups. Sepsis-induced ALI model was established by cecal ligation and puncture. Sham-operated group: gavage with 2 ml saline and no surgical treatment. Model group: surgery was performed and 2 ml saline was gavaged. Liangge Powder low, medium and high dose groups: surgery and gavage of Liangge Powder 3.9, 7.8 and 15.6 g/kg, respectively. To measure the wet/dry mass ratio of rats lung tissue and evaluate the permeability of alveolar capillary barrier. Lung tissue were stained with hematoxylin and eosin for histomorphological analysis. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL) -6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The relative protein expression levels of p-phosphatidylinositol 3-kinase (PI3K), p-protein kinase B (AKT), and p-ertracellular regulated protein kinases (ERK) were detected via Western blot analysis. Results: Network pharmacology analysis indicated that 177 active compounds of Liangge Powder were selected. A total of 88 potential targets of Liangge Powder on sepsis-induced ALI were identified. 354 GO terms of Liangge Powder on sepsis-induced ALI and 108 pathways were identified using GO and KEGG analysis. PI3K/AKT signaling pathway was recognized to play an important role for Liangge Powder against sepsis-induced ALI. Compared with the sham-operated group, the lung tissue wet/dry weight ratio of rats in the model group (6.35±0.95) was increased (P<0.001). HE staining showed the destruction of normal structure of lung tissue. The levels of IL-6 [ (392.36±66.83) pg/ml], IL-1β [ (137.11±26.83) pg/ml] and TNF-α [ (238.34±59.36) pg/ml] were increased in the BALF (P<0.001, =0.001, <0.001), and the expression levels of p-PI3K, p-AKT and p-ERK1/2 proteins (1.04±0.15, 0.51±0.04, 2.31±0.41) were increased in lung tissue (P=0.002, 0.003, 0.005). The lung histopathological changes were reduced in each dose group of Liangge Powder compared with the model group. Compared with the model group, the wet/dry weight ratio of lung tissue (4.29±1.26) was reduced in the Liangge Powder medium dose group (P=0.019). TNF-α level [ (147.85±39.05) pg/ml] was reduced (P=0.022), and the relative protein expression levels of p-PI3K (0.37±0.18) and p-ERK1/2 (1.36±0.07) were reduced (P=0.008, 0.017). The wet/dry weight ratio of lung tissue (4.16±0.66) was reduced in the high-dose group (P=0.003). Levels of IL-6, IL-1β and TNF-α[ (187.98±53.28) pg/ml, (92.45±25.39) pg/ml, (129.77±55.94) pg/ml] were reduced (P=0.001, 0.027, 0.018), and relative protein expression levels of p-PI3K, p-AKT and p-ERK1/2 (0.65±0.05, 0.31±0.08, 1.30±0.12) were reduced (P=0.013, 0.018, 0.015) . Conclusion: Liangge Powder has therapeutic effects in rats with sepsis-induced ALI, and the mechanism may be related to the inhibition of ERK1/2 and PI3K/AKT pathway activation in lung tissue.

Effects of Nintedanib associated with Shenfu Injection on paraquat-induced lung injury in rats / 中华劳动卫生职业病杂志

Objective: To study the effects of Nintedanib associated with Shenfu Injection on lung injury induced by paraquat (PQ) intoxication. Methods: In September 2021, a total of 90 SD rats were divided into 5 groups in random, namely control group, PQ poisoning group, Shenfu Injection group, Nintedanib group and associated group, 18 rats in each group. Normal saline was given by gavage route to rats of control group, 20% PQ (80 mg/kg) was administered by gavage route to rats of other four groups. 6 hours after PQ gavage, Shenfu Injection group (12 ml/kg Shenfu Injection), Nintedanib group (60 mg/kg Nintedanib) and associated group (12 ml/kg Shenfu Injection and 60 mg/kg Nintedanib) were administered with medicine once a day. The levels of serum transforming growth factor beta1 (TGF-β1), interleukin-1 beta (IL-1β) were determined at 1, 3 and 7 d, respectively. The pathological changes of lung tissue, the ratio of wet weight and dry weight (W/D) of lung tissue, the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in lung tissue were observed and determined after 7 d. Western blot was used to analyse the expression levels of fibroblast growth factor receptor 1 (FGFR1), platelet derivation growth factor receptor alpha (PDGFRα), vascular endothelial growth factor receptor 2 (VEGFR2) in lung tissue after 7 d. Results: The levels of TGF-β1, IL-1β in all poisoning groups went up first and then went down. The levels of TGF-β1, IL-1β in associated group at 1, 3, 7 d were lower than that of PQ poisoning group, Shenfu Injection group and Nintedanib group at the same point (P<0.05). Pathological changes of lung tissue under the light microscopes showed that the degrees of hemorrhage, effusion and infiltration of inflammatory cells inside the alveolar space of Shenfu Injection group, Nintedanib group and associated group were milder than that of PQ poisoning group, and the midest in associated group. Compared with control group, the W/D of lung tissue was higher, the level of MDA in lung tissue was higher, while the level of SOD was lower, the expressions of FGFR1, PDGFRα and VEGFR2 in lung tissue were higher in PQ poisoning group (P<0.05). Compared with PQ poisoning group, Shenfu Injection group and Nintedanib group, the W/D of lung tissue was lower, the level of MDA in lung tissue was lower, while the level of SOD was higher, the expressions of FGFR1, PDGFRα and VEGFR2 in lung tissue were lower in associated group (P<0.05) . Conclusion: Nintedanib associated with Shenfu Injection can relieve lung injury of rats induced by PQ, which may be related to Nintedanib associated with Shenfu Injection can inhibit the activation of TGF-β1 and the expressions of FGFR1, PDGFRα, VEGFR2 in lung tissue of rats.

Tanshinone IIA prevents acute lung injury by regulating macrophage polarization / 中西医结合学报

OBJECTIVE@#Acute lung injury (ALI) is a serious respiratory dysfunction caused by pathogen or physical invasion. The strong induced inflammation often causes death. Tanshinone IIA (Tan-IIA) is the major constituent of Salvia miltiorrhiza Bunge and has been shown to display anti-inflammatory effects. The aim of the current study was to investigate the effects of Tan-IIA on ALI.@*METHODS@#A murine model of lipopolysaccharide (LPS)-induced ALI was used. The lungs and serum samples of mice were extracted at 3 days after treatment. ALI-induced inflammatory damages were confirmed from cytokine detections and histomorphology observations. Effects of Tan-IIA were investigated using in vivo and in vitro ALI models. Tan-IIA mechanisms were investigated by performing Western blot and flow cytometry experiments. A wound-healing assay was performed to confirm the Tan-IIA function.@*RESULTS@#The cytokine storm induced by LPS treatment was detected at 3 days after LPS treatment, and alveolar epithelial damage and lymphocyte aggregation were observed. Tan-IIA treatment attenuated the LPS-induced inflammation and reduced the levels of inflammatory cytokines released not only by inhibiting neutrophils, but also by macrophage. Moreover, we found that macrophage activation and polarization after LPS treatment were abrogated after applying the Tan-IIA treatment. An in vitro assay also confirmed that including the Tan-IIA supplement increased the relative amount of the M2 subtype and decreased that of M1. Rebalanced macrophages and Tan-IIA inhibited activations of the nuclear factor-κB and hypoxia-inducible factor pathways. Including Tan-IIA and macrophages also improved alveolar epithelial repair by regulating macrophage polarization.@*CONCLUSION@#This study found that while an LPS-induced cytokine storm exacerbated ALI, including Tan-IIA could prevent ALI-induced inflammation and improve the alveolar epithelial repair, and do so by regulating macrophage polarization.

Effects of propofol pretreatment on lung morphology and heme oxygenase-1 expression in oleic acid-induced acute lung injury in rats

Abstract Purpose: To investigate the effects of propofol pretreatment on lung morphology and heme oxygenase-1 expression in oleic acid -induced acute lung injury in rats. Methods: A total of 32 male Sprague-Dawley rats (250-300g) were randomly divided into the following four groups (n=8/group): group C, group OA, group OA+PR, and group OA+IX to compare related parameter changes. Results: PaO2, PCO2, and PaO2/FiO2 were significantly different among the four treatment groups (P<0.05 or P<0.01). Lung wet/dry weight ratio and HO-1 protein expression also significantly differed among the groups (P<0.01). Immunohistochemistry showed that the expression of HO-1 in group OA+PR was stronger than those in groups OA, OA+IX, and C. Light microscopy revealed that pathological changes in lung tissues in group OA+PR were milder than those in group OA and group OA+IX. Electron microscopy showed that alveolar type II epithelial cell ultrastructure in group OA was relatively irregular with cell degeneration and disintegration and cytoplasmic lamellar bodies were vacuolized. Changes in group OA+PR were milder than those in group OA; however, they were more severe in group OA+IX than in group OA. Conclusion: Propofol significantly increases the expression of HO-1 in the lung tissueand prevents changes in lung morphology due to ALI in rats.

Saquinavir plus methylprednisolone ameliorates experimental acute lung injury

Glucocorticoid insensitivity is an important barrier to the treatment of several inflammatory diseases, including acute lung injury (ALI). Saquinavir (SQV) is an inhibitor of the human immunodeficiency virus protease, and the therapeutic effects of SQV in ALI accompanied with glucocorticoid insensitivity have not been previously investigated. In this study, the effects of SQV on lipopolysaccharide (LPS)-mediated injury in human pulmonary microvascular endothelial cells (HPMECs), human type I alveolar epithelial cells (AT I), and alveolar macrophages were determined. In addition, the effects of SQV on an LPS-induced ALI model with or without methylprednisolone (MPS) were studied. In LPS-stimulated HPMECs, SQV treatment resulted in a decrease of high mobility group box 1 (HMGB1), phospho-NF-κB (p-NF-κB), and toll-like receptor 4 (TLR4), and an increase of VE-cadherin. Compared to MPS alone, MPS plus SQV attenuated the decrease of glucocorticoid receptor alpha (GRα) and IκBα in LPS-stimulated HPMECs. HMGB1, TLR4, and p-NF-κB expression were also lessened in LPS-stimulated alveolar macrophages with SQV treatment. In addition, SQV reduced the injury in human AT I with a decrease of HMGB1 and p-NF-κB, and with an increase of aquaporin 5 (AQP 5). SQV ameliorated the lung injury caused by LPS in rats with reductions in vascular permeability, myeloperoxidase activity (MPO) and histopathological scores, and with lowered HMGB1, TLR4, and p-NF-κB expression, but with enhanced VE-cadherin expression. By comparison, SQV plus MPS increased GRα and IκBα in lung tissues of rats with ALI. This study demonstrated that SQV prevented experimental ALI and improved glucocorticoid insensitivity by modulating the HMGB1/TLR4 pathway.

Galantamine protects against lipopolysaccharide-induced acute lung injury in rats

Lipopolysaccharide (LPS)-induced endotoxemia triggers the secretion of proinflammatory cytokines and can cause acute lung injury (ALI). The high mobility group box 1 (HMGB1) protein plays an important role as a late mediator of sepsis and ALI. Galantamine (GAL) is a central acetylcholinesterase inhibitor that inhibits the expression of HMGB1. This study evaluated the effects of GAL by measuring levels of inflammatory mediators and observing histopathological features associated with LPS-induced ALI. Sixty 8-10 week old male Sprague-Dawley rats (200-240 g) were randomized into three groups as follows: control group, LPS group (7.5 mg/kg LPS), and LPS+GAL group (5 mg/kg GAL before LPS administration). Histopathological examination of lung specimens obtained 12 h after LPS administration was performed to analyze changes in wet-to-dry (W/D) weight ratio, myeloperoxidase (MPO) activity, and HMGB1 expression level. Additionally, plasma concentrations of tumor necrosis factor-α, interleukin-6, and HMGB1 were measured using an enzyme-linked immunosorbent assay at 0 (baseline), 3, 6, 9, and 12 h after LPS administration. Mortality in the three groups was recorded at 72 h. LPS-induced ALI was characterized by distortion of pulmonary architecture and elevation of MPO activity, W/D weight ratio, and levels of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-6, and HMGB1. Pretreatment with GAL significantly reduced the LPS-induced lung pathological changes, W/D weight ratio, levels of pro-inflammatory cytokines and MPO activity (ANOVA). Moreover, GAL treatment significantly decreased the mortality rate (ANOVA). In conclusion, we demonstrated that GAL exerted a protective effect on LPS-induced ALI in rats.

Effect of hypertonic saline treatment on the inflammatory response after hydrochloric acid-induced lung injury in pigs

OBJECTIVES: Hypertonic saline has been proposed to modulate the inflammatory cascade in certain experimental conditions, including pulmonary inflammation caused by inhaled gastric contents. The present study aimed to assess the potential anti-inflammatory effects of administering a single intravenous dose of 7.5% hypertonic saline in an experimental model of acute lung injury induced by hydrochloric acid. METHODS: Thirty-two pigs were anesthetized and randomly allocated into the following four groups: Sham, which received anesthesia and were observed; HS, which received intravenous 7.5% hypertonic saline solution (4 ml/kg); acute lung injury, which were subjected to acute lung injury with intratracheal hydrochloric acid; and acute lung injury + hypertonic saline, which were subjected to acute lung injury with hydrochloric acid and treated with hypertonic saline. Hemodynamic and ventilatory parameters were recorded over four hours. Subsequently, bronchoalveolar lavage samples were collected at the end of the observation period to measure cytokine levels using an oxidative burst analysis, and lung tissue was collected for a histological analysis. RESULTS: Hydrochloric acid instillation caused marked changes in respiratory mechanics as well as blood gas and lung parenchyma parameters. Despite the absence of a significant difference between the acute lung injury and acute lung injury + hypertonic saline groups, the acute lung injury animals presented higher neutrophil and tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-8 levels in the bronchoalveolar lavage analysis. The histopathological analysis revealed pulmonary edema, congestion and alveolar collapse in both groups; however, the differences between groups were not significant. Despite the lower cytokine and neutrophil levels observed in the acute lung injury + hypertonic saline group, significant differences were not observed among the treated and non-treated groups. ...

Propofol pretreatment attenuates lipopolysaccharide-induced acute lung injury in rats by activating the phosphoinositide-3-kinase/Akt pathway

The aim of this study was to investigate the effect of propofol pretreatment on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the role of the phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) pathway in this procedure. Survival was determined 48 h after LPS injection. At 1 h after LPS challenge, the lung wet- to dry-weight ratio was examined, and concentrations of protein, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF) were determined using the bicinchoninic acid method or ELISA. Lung injury was assayed via lung histological examination. PI3K and p-Akt expression levels in the lung tissue were determined by Western blotting. Propofol pretreatment prolonged survival, decreased the concentrations of protein, TNF-α, and IL-6 in BALF, attenuated ALI, and increased PI3K and p-Akt expression in the lung tissue of LPS-challenged rats, whereas treatment with wortmannin, a PI3K/Akt pathway specific inhibitor, blunted this effect. Our study indicates that propofol pretreatment attenuated LPS-induced ALI, partly by activation of the PI3K/Akt pathway.

Ethyl-pyruvate reduces lung injury matrix metalloproteinases and cytokines and improves survival in experimental model of severe acute pancreatitis

PURPOSE: To investigate if the ethyl-pyruvate solution could reduce mortality in AP and/or diminish the acute lung injury. METHODS: Forty male rats, weighing between 270 to 330 grams were operated. An experimental model of severe AP by injection of 0.1ml/100g of 2.5% sodium taurocholate into the bilio-pancreatic duct was utilized. The rats were divided into two groups of ten animals each: CT - control (treatment with 50ml/kg of Ringer's solution, intraperitoneal) and EP (treatment with 50ml/kg of Ringer ethyl- pyruvate solution, intra-peritoneal), three hours following AP induction. After six hours, a new infusion of the treatment solution was performed in each group. Two hours later, the animals were killed and the pulmonary parenchyma was resected for biomolecular analysis, consisting of: interleukin, myeloperoxidase, MDA, nitric oxide, metalloproteinases and heat shock protein. In the second part of the experiment, another, 20 rats were randomly divided into EP and CT groups, in order to evaluate a survival comparison between the two groups. RESULTS: There were no significant differences in IL-1B,IL-10, MMP-9, HSP70, nitric oxide, MPO, MDA (lipidic peroxidation) concerning both groups. The levels of IL-6 were significantly diminished in the EP group. Furthermore, the MMP-2 levels were also reduced in the EP group (p<0.05). The animals from the EP treatment groups had improved survival, when compared to control group (p<0.05). CONCLUSION: The ethyl-pyruvate diminishes acute lung injury inflammatory response in acute pancreatitis and ameliorates survival when compared to control group, in the experimental model of necrotizing acute pancreatitis.

Propofol exerts anti-inflammatory effects in rats with lipopolysaccharide-induced acute lung injury by inhibition of CD14 and TLR4 expression

We investigated the effect of propofol (Prop) administration (10 mg kg-1 h-1, intravenously) on lipopolysaccharide (LPS)-induced acute lung injury and its effect on cluster of differentiation (CD) 14 and Toll-like receptor (TLR) 4 expression in lung tissue of anesthetized, ventilated rats. Twenty-four male Wistar rats were randomly divided into three groups of 8 rats each: control, LPS, and LPS+Prop. Lung injury was assayed via blood gas analysis and lung histology, and tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels were determined in bronchoalveolar lavage fluid using ELISA. Real-time polymerase chain reaction was used to detect CD14 and TLR4 mRNA levels, and CD14 and TLR4 protein expression was determined by Western blot. The pathological scores were 1.2 ± 0.9, 3.3 ± 1.1, and 1.9 ± 1.0 for the control, LPS, and LPS+Prop groups, respectively, with statistically significant differences between control and LPS groups (P < 0.05) and between LPS and LPS+Prop groups (P < 0.05). The administration of LPS resulted in a significant increase in TNF-α and IL-1β levels, 7- and 3.5-fold, respectively (P < 0.05), while treatment with propofol partially blunted the secretion of both cytokines (P < 0.05). CD14 and TLR4 mRNA levels were increased in the LPS group (1.48 ± 0.05 and 1.26 ± 0.03, respectively) compared to the control group (1.00 ± 0.20 and 1.00 ± 0.02, respectively; P < 0.05), while propofol treatment blunted this effect (1.16 ± 0.05 and 1.12 ± 0.05, respectively; P < 0.05). Both CD14 and TLR4 protein levels were elevated in the LPS group compared to the control group (P < 0.05), while propofol treatment partially decreased the expression of CD14 and TLR4 protein versus LPS alone (P < 0.05). Our study indicates that propofol prevents lung injury, most likely by inhibition of CD14 and TLR4 expression.

Acute pulmonary injury induced by experimental muscle trauma / Lesão pulmonar aguda induzida por trauma muscular experimental

PURPOSE: To develop an easily reproducible model of acute lung injury due to experimental muscle trauma in healthy rats. METHODS: Eighteen adult Wistar rats were randomized in 3 groups (n=6): G-1- control, G-2 - saline+trauma and G-3 - dexamethasone+trauma. Groups G-1 and G-2 were treated with saline 2,0ml i.p; G-3 rats were treated with dexamethasone (DE) (2 mg/kg body weight i.p.). Saline and DE were applied 2h before trauma and 12h later. Trauma was induced in G-2 and G-3 anesthetized (tribromoethanol 97 percent 100 ml/kg i.p.) rats by sharp section of anterior thigh muscles just above the knee, preserving major vessels and nerves. Tissue samples (lung) were collected for myeloperoxidase (MPO) assay and histopathological evaluation. RESULTS: Twenty-four hours after muscle injury there was a significant increase in lung neutrophil infiltration, myeloperoxidase activity and edema, all reversed by dexamethasone in G-3. CONCLUSION: Trauma by severance of thigh muscles in healthy rats is a simple and efficient model to induce distant lung lesions.

OBJETIVO: Desenvolver um modelo facilmente reprodutível de lesão pulmonar aguda decorrente de trauma muscular experimental em ratos sadios. MÉTODOS: Dezoito ratos Wistar adultos foram randomizados em 3 grupos (n=6): G-1-controle, G-2 - trauma+salina e G-3 - trauma+dexametasona. Grupos G-1 e G-2 foram tratados com salina 2,0 ml ip, G-3 ratos foram tratados com dexametasona (DE) (2 mg/kg peso corporal ip). Salina e DE foram aplicadas 2h antes e 12h depois do trauma. Trauma foi induzido em ratos G-2 e G-3 anestesiados (tribromoetanol 97 por cento de 100 ml/kg, i.p.) por secção da musculatura anterior da coxa logo acima da articulação do joelho, preservando os grandes vasos e nervos. Amostras de tecido (pulmão) foram coletadas para avaliação da mieloperoxidase (MPO), e exames histopatológicos. RESULTADOS: Vinte e quatro horas após a indução da lesão muscular houve um aumento significativo na infiltração de neutrófilos pulmonares, atividade da mieloperoxidase e edema, todos revertidos por dexametasona, no G-3. CONCLUSÃO: O trauma decorrente da secção dos músculos da coxa em ratos saudáveis é um modelo simples e eficaz para induzir lesões pulmonares à distância.