OBJECTIVES: To investigate the effect of amentoflavone (AF) for alleviating lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and inhibiting NLRP3/ASC/Caspase-1 axis-mediated pyroptosis. METHODS: Female BALB/c mice were randomly divided into control group, LPS group, and AF treatment groups at low, moderate and high doses (n=12). ALI models were established by tracheal LPS instillation, and in AF treatment groups, AF was administered by gavage 30 min before LPS instillation. Six hours after LPS instillation, the mice were euthanized for examining lung tissue histopathological changes, protein levels in BALF, and MPO levels in the lung tissue. In the in vitro experiment, RAW264.7 cells were pretreated with AF, AC (a pyroptosis inhibitor), or their combination for 2 h before stimulation with LPS and ATP. The changes in cell proliferation and viability were detected using CCK-8 assay, and IL-1β, IL-6, IL-18, and TNF-α levels were determined with ELISA. Immunohistochemistry, immunofluorescence assay, and immunoblotting were used to detect the protein levels of NLRP3, ASC, cleaved caspase-1, and GSDMD N in rat lung tissues and the treated cells. RESULTS: In mice with LPS exposure, AF treatment significantly improved lung pathologies and edema, reduced protein levels in BALF and pulmonary MPO level, inhibited the high expression of NLRP3/ASC/Aspase-1 axis, reduced the expression of GSDMD N, and lowered the release of IL-1β, IL-6, IL-18, and TNF‑α. In RAW264.7 cells with LPS and ATP stimulation, AF pretreatment effectively reduced cell death, inhibited activation of the NLRP3/ASC/Aspase-1 axis, and reduced GSDMD N expression and the inflammatory factors. The pyroptosis inhibitor showed a similar effect to AF, and their combination produced more pronounced effects in RAW264.7 cells. CONCLUSIONS Amentoflavone can alleviate ALI in mice possibly by inhibiting NLRP3/ASC/Caspase-1 axis-mediated cell pyroptosis.
Animals ; Pyroptosis/drug effects* ; Acute Lung Injury/pathology* ; Mice ; Mice, Inbred BALB C ; Female ; Lipopolysaccharides ; Biflavonoids/pharmacology* ; RAW 264.7 Cells ; NLR Family, Pyrin Domain-Containing 3 Protein ; Caspase 1/metabolism* ; Lung

OBJECTIVES: To compare the anti-inflammatory, antibacterial and analgesic effects of Yinqiao Powder (YQS) formulated granules and decoction. METHODS: We first evaluated the anti-inflammatory effects of the two dosage forms of YQS in a LPS-induced RAW 264.7 cell model using RT-qPCR and Western blotting. We further constructed zebrafish models of inflammation by copper sulfate exposure, caudal fin transection, or LPS and Poly (I:C) microinjection, and evaluated anti-inflammatory effects of YQS granules and decoction by examining neutrophil aggregation and HE staining findings. In a mouse model of acute lung injury (ALI) induced by intratracheal LPS instillation, the effects of YQS gavage at 10, 15, and 20 g/kg on lung pathologies were evaluated by calculating lung wet-dry weight ratio and using HE staining, ELISA and Western blotting. The microbroth dilution method was used to evaluate the antibacterial effect of YQS. Mouse pain models established by hot plate and intraperitoneal injection of glacial acetic acid were used to evaluate the analgesic effects of YQS at 10, 15, and 20 g/kg. RESULTS: Both YQS granules and decoction significantly reduced TNF-α, IL-6, and IL-1β expressions and p-STAT3 (Tyr 705) phosphorylation level in LPS-induced RAW 264.7 cells, and obviously inhibited neutrophil aggregation in the zebrafish models. In ALI mice, YQS granules and decoction effectively ameliorated lung injury, lowered lung wet-dry weight ratio, and reduced p-STAT3 (Tyr 705) expression and TNF-α and IL-6 levels. YQS produced obvious antibacterial effect at the doses of 15.63 and 31.25 mg/mL, and significantly reduced body torsion and increased pain threshold in the mouse pain models. CONCLUSIONS The two dosage forms of TQS have similar anti-inflammatory, antibacterial and analgesic effects with only differences in their inhibitory effect on TNF-α, IL-6 and IL-1β mRNA expressions in LPS-induced RAW 264.7 cells.
Animals ; Mice ; Drugs, Chinese Herbal/pharmacology* ; Anti-Inflammatory Agents/pharmacology* ; Analgesics/pharmacology* ; RAW 264.7 Cells ; Zebrafish ; Anti-Bacterial Agents/pharmacology* ; Powders ; Tumor Necrosis Factor-alpha/metabolism* ; Acute Lung Injury/drug therapy* ; Interleukin-6/metabolism* ; Lipopolysaccharides

OBJECTIVES: To develop an E-selectin-targeting nanomedicine delivery system that competitively inhibits E-selectin-neutrophil ligand binding to block neutrophil adhesion to vessels and suppress their recruitment to the lesion sites. METHODS: Doxorubicin hydrochloride (DOX)-loaded liposomes (IEL-Lip/DOX) conjugated with E-selectin-affinity peptide IELLQARC were developed using a post-insertion method. Two formulations [2-1P: Mol(PC): Mol(DPI)=100:1; 2-3P: 100:3] were prepared and their modification density and in vitro release characteristics were determined. Their targeting efficacy was assessed in a cell model of LPS-induced inflammation, a mouse model of acute lung injury (ALI), a rat femoral artery model of physical injury-induced inflammation, and a zebrafish model of local inflammation. RESULTS: The prepared IEL-Lip/DOX 2-1P and 2-3P had peptide modification densities of 4.76 and 7.57 pmoL/cm², respectively. Compared with unmodified liposomes, IEL-Lip/DOX exhibited significantly reduced 48-h cumulative release rates at pH 5.5. In the inflammation cell model, IEL-Lip/DOX showed increased uptake by activated inflammatory endothelial cells, and 2-1P exhibited a higher trans-endothelial ability. In ALI mice, the fluorescence intensity of IEL-Lip/Cy5.5 increased significantly in lung tissues by 53.71% [Z-(2-1P)] and 93.41% [Z-(2-3P)], and 2-1P had an increased distribution by 24.19% in the inflammatory lung tissue compared to normal mouse lung tissue. In rat femoral artery models, 2-1P had greater injured/normal vessel fluorescence intensity contrast. In the zebrafish models, both 2-1P and 2-3P showed increased aggregation at the site of inflammation. CONCLUSIONS This E-selectin-targeting nanomedicine delivery system efficiently targets activated inflammatory endothelial cells to increase drug concentration at the inflammatory site, which sheds light on new strategies for treating neutrophil-mediated inflammatory diseases and practicing the concept of "one drug for multiple diseases".
Animals ; Liposomes ; Rats ; Nanomedicine ; E-Selectin ; Drug Delivery Systems ; Inflammation/drug therapy* ; Mice ; Doxorubicin/analogs & derivatives* ; Zebrafish ; Acute Lung Injury/drug therapy*

Mechanical ventilation (MV) is currently widely used in the treatment of respiratory failure and anesthesia surgery, and is a commonly used respiratory support method for critically ill patients; however, improper usage of MV can lead to ventilator-induced lung injury (VILI), which poses a significant threat to patient life. Alveolar epithelial cell (AEC) has the functions of mechanosensation and mechanotransduction. Physiological mechanical stretching is beneficial for maintaining the lineage homeostasis and normal physiological functions of AEC cells, while excessive mechanical stretching can cause damage to AEC cells. Damage to AEC cells is an important aspect in the occurrence and development of VILI. Understanding the effects of mechanical stretching on AEC cells is crucial for developing safe and effective MV strategies, preventing the occurrence of VILI, and improving the clinical prognosis of VILI patients. From the perspective of cell mechanics, this paper aims to briefly elucidate the mechanical properties of AEC cells, mechanosensation and mechanotransduction of mechanical stretching in AEC cells, and the injury and repair of AEC cells under mechanical stretch stimulation, and potential mechanisms with the goal of helping clinical doctors better understand the pathophysiological mechanism of VILI caused by MV, improve their understanding of VILI, provide safer and more effective strategies for the use of clinical MV, and provide theoretical basis for the prevention and treatment of VILI.
Humans ; Mechanotransduction, Cellular ; Ventilator-Induced Lung Injury ; Stress, Mechanical ; Alveolar Epithelial Cells ; Respiration, Artificial/adverse effects* ; Epithelial Cells ; Pulmonary Alveoli/cytology* ; Animals

Post-cardiac arrest brain injury (PCABI) remains the main cause of death and poor prognosis in patients after resuscitation. In June 2024, the International Liaison Committee on Resuscitation (ILCOR) released a scientific statement on improving the prognosis of PCABI based on relevant research progress. The statement proposed the pathological mechanism of PCABI, explored the reasons why previous preclinical data could not be translated into clinical practice, and outlined possible future directions for advancement. This article interprets the key content of the 2024 ILCOR scientific statement on improving the prognosis of PCABI, hoping to provide reference and assistance for domestic medical staff to understand and apply this scientific statement.
Humans ; Heart Arrest/therapy* ; Brain Injuries/therapy* ; Cardiopulmonary Resuscitation ; Prognosis ; Resuscitation

OBJECTIVE: To investigate the mechanism of human embryonic stem cell-derived mesenchymal stem cells (hESC-MSC) in alleviating brain injury after resuscitation in swine with cardiac arrest (CA). METHODS: Twenty-nine healthy male large white swine were randomly divided into Sham group (n = 9), cardiopulmonary resuscitation (CPR) group (n = 10) and hESC-MSC group (n = 10). The Sham group only completed animal preparation. In CPR group and hESC-MSC group, the swine model of CA-CPR was established by inducing ventricular fibrillation for 10 minutes with electrical stimulation and CPR for 6 minutes. At 5 minutes after successful resuscitation, hESC-MSC 2.5×10⁶/kg was injected via intravenous micropump within 1 hour in hESC-MSC group. Venous blood samples were collected before resuscitation and at 4, 8, 24, 48 and 72 hours of resuscitation. The levels of neuron specific enolase (NSE) and S100B protein (S100B) were detected by enzyme linked immunosorbent assay (ELISA). At 24, 48 and 72 hours of resuscitation, neurological deficit score (NDS) and cerebral performance category (CPC) were used to evaluate the neurological function of the animals. Three animals from each group were randomly selected and euthanized at 24, 48, and 72 hours of resuscitation, and the hippocampus tissues were quickly obtained. Immunofluorescence staining was used to detect the distribution of hESC-MSC in hippocampus. Immunohistochemical staining was used to detect the activation of astrocytes and microglia and the survival of neurons in the hippocampus. The degree of apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL). RESULTS: The serum NSE and S100B levels of brain injury markers in CPR group and hESC-MSC group were significantly higher than those in Sham group at 24 hours of resuscitation, and then gradually increased. The levels of NSE and S100B in serum at each time of resuscitation in hESC-MSC group were significantly lower than those in CPR group [NSE (μg/L): 20.69±3.62 vs. 28.95±3.48 at 4 hours, 27.04±5.56 vs. 48.59±9.22 at 72 hours; S100B (μg/L): 2.29±0.39 vs. 3.60±0.73 at 4 hours, 2.38±0.15 vs. 3.92±0.50 at 72 hours, all P < 0.05]. In terms of neurological function, compared with the Sham group, the NDS score and CPC score in the CPR group and hESC-MSC group increased significantly at 24 hours of resuscitation, and then gradually decreased. The NDS and CPC scores of hESC-MSC group were significantly lower than those of CPR group at 24 hours of resuscitation (NDS: 111.67±20.21 vs. 170.00±21.79, CPC: 2.33±0.29 vs. 3.00±0.00, both P < 0.05). The expression of hESC-MSC positive markers CD73, CD90 and CD105 in the hippocampus of hESC-MSC group at 24, 48 and 72 hours of resuscitation was observed under fluorescence microscope, indicating that hESC-MSC could homing to the damaged hippocampus. In addition, compared with Sham group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of CPR group were significantly increased, and the proportion of neurons was significantly decreased at 24, 48 and 72 hours of resuscitation. Compared with CPR group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of hESC-MSC group decreased and the proportion of neurons increased significantly at 24 hours of resuscitation [proportion of astrocytes: (14.33±1.00)% vs. (30.78±2.69)%, proportion of microglia: (12.00±0.88)% vs. (27.89±5.68)%, apoptotic index: (12.89±3.86)% vs. (52.33±7.77)%, proportion of neurons: (39.44±3.72)% vs. (28.33±1.53)%, all P < 0.05]. CONCLUSIONS Application of hESC-MSC at the early stage of resuscitation can reduce the brain injury and neurological dysfunction after resuscitation in swine with CA. The mechanism may be related to the inhibition of immune cell activation, reduction of cell apoptosis and promotion of neuronal survival.
Animals ; Heart Arrest/therapy* ; Cardiopulmonary Resuscitation ; Swine ; Humans ; Male ; Human Embryonic Stem Cells/cytology* ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells/cytology* ; Phosphopyruvate Hydratase/blood* ; Brain Injuries/therapy* ; S100 Calcium Binding Protein beta Subunit ; Apoptosis ; Disease Models, Animal

Mechanical ventilation is commonly employed for respiratory support in patients with respiratory failure. Despite the optimization of ventilator parameters and treatment methods, mechanical ventilation can still lead to both acute and chronic lung injury in patients with acute respiratory distress syndrome (ARDS) as well as in those without ARDS, a phenomenon referred to as ventilator-induced lung injury (VILI). VILI can be categorized into four types: barotrauma, volumetric injury, atelectasis injury, and biotic injury. Among these, biotic injury, characterized by inflammation, plays a significant role in the pathogenesis of VILI. Numerous studies have investigated the inflammatory mechanisms underlying VILI; however, these mechanisms remain complex and not entirely understood. At present, clinical practice lacks specific prevention and treatment strategies for VILI, aside from the implementation of protective ventilation strategies. Long non-coding RNAs (lncRNA) are a category of non-coding RNA longer than 200 nucleotides. LncRNAs regulate physiological and pathological processes such as cell proliferation, apoptosis, inflammatory response, and immune regulation, this regulation occurs through mechanisms such as modulating gene activity, inhibiting specific states, assisting in transcription initiation, affecting pre-mRNA splicing modifications, influencing translation processes, and expressing biofunctional peptides. They play an important role in the course of multiple diseases. Studies have shown that compared with control animals and cell models, lncRNAs are differentially expressed in VILI animal models and cell stretch models. Experiments have verified that certain lncRNAs play a crucial role in the pathogenesis of VILI by regulating the expression of inflammatory factors, the transformation of macrophage types, neutrophil activation, and cell apoptosis. Given the adverse effects of VILI on mechanical ventilation in critically ill patients, the important role of lncRNAs in biological regulation, and the urgent need to explore more effective strategies for the prevention and treatment of VILI, this paper summarizes the mechanisms through which lncRNA contributes to the VILI process, and discusses its possibility as a diagnostic and therapeutic target of VILI, in order to provide a reference for the clinical treatment of VILI.
RNA, Long Noncoding ; Ventilator-Induced Lung Injury ; Humans ; Respiration, Artificial/adverse effects* ; Animals ; Respiratory Distress Syndrome ; Apoptosis

Since the beginning of the 21st century, the severe respiratory infectious diseases worldwide [such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), influenza A H1N1 and novel coronavirus infection have attracted wide attention from all walks of life due to their superior pathogenicity and transmissibility. Aerosols-carrying pathogens are the main transmission route of many severe respiratory infectious diseases, which can lead to severe respiratory failure and even acute respiratory distress syndrome (ARDS) in infected individuals. Mechanical ventilation is the primary treatment for ARDS, and the small tidal volume, appropriate level of positive end-expiratory pressure based lung protective ventilation strategy can effectively reduce the incidence of ventilator-induced lung injury (VILI). However, in the process of clinical treatment, it is sometimes necessary to briefly disconnect the connection between the artificial airway and the ventilator circuit, which will not only cause the residual aerosol in the respiratory system to spill out and pollute the surrounding environment, increase the risk of nosocomial infection including medical staff, but also interfere with the implementation of lung protective ventilation strategy and aggravate ventilator-induced lung injury. In addition, studies have shown that a lot of medical staff have nosocomial infections, especially staff involved in tracheal intubation, extubation and other airway related operations. In addition to enhancing personal protective measures, it is crucial to safeguard healthcare workers from aerosol contamination and minimize associated risks during airway management. At present, there are few researches on the temporary sealing of airway lines and ventilator system, and there is a lack of clear guidance. This review summarizes the research status in related fields to provide a reference for corresponding solutions and programs.
Humans ; Respiratory Distress Syndrome/etiology* ; Respiration, Artificial ; Ventilator-Induced Lung Injury/prevention & control* ; Severe Acute Respiratory Syndrome ; COVID-19 ; Clinical Relevance

OBJECTIVE: To investigate whether the G protein-coupled estrogen receptor (GPER) can attenuates acute lung injury in mice with exertional heat stroke (EHS) by inhibiting ferroptosis. METHODS: Sixty SPF-grade male C57BL/6 mice were randomly divided into four groups: normal control group (control group), EHS model group (EHS group), dimethyl sulfoxide (DMSO) solvent group (EHS+DMSO group), and GPER-specific agonist G1 group (EHS+G1 group), with 15 mice in each group. All mice underwent 14 days of adaptive training at 24-26 centigrade before modeling, and the EHS model was established using a high-temperature treadmill device. After successful modeling, the mice were allowed to cool naturally at room temperature. In the EHS+G1 group, 40 μg/kg of the GPER-specific agonist G1 was slowly injected intraperitoneally immediately after modeling. In the EHS+DMSO group, 40 μg/kg of DMSO was slowly injected intraperitoneally immediately after modeling. The control group received no treatment. Five hours after modeling, abdominal aortic blood was collected, and lung tissues were harvested after euthanasia. The lung coefficient was calculated to evaluate lung injury. Lung histopathological changes were observed under a light microscope after hematoxylin-eosin (HE) staining, and a lung histopathological score was assigned. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), malondialdehyde (MDA), and Fe²⁺ in lung tissue. Immunofluorescence was used to detect the expression of glutathione peroxidase 4 (GPX4). Real-time polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of GPX4, ferroportin 1 (FPN1), and ferritin heavy chain 1 (FTH1). Western blotting was performed to detect the protein expression of GPX4, FPN1, and FTH1. RESULTS: Compared with the control group, the lung coefficient and lung histopathological score were significantly increased in the EHS group. HE staining showed significant thickening and unevenness of the alveolar septa and alveolar walls, partial alveolar collapse, and extensive erythrocyte, inflammatory cell, and plasma-like material extravasation in the alveolar spaces. Serum levels of TNF-α, IL-1β, MDA, and Fe²⁺ were significantly elevated. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue. Western blotting and RT-PCR showed significantly reduced protein and mRNA expression of GPX4, FPN1, and FTH1 in lung tissue. Compared with the EHS group, the EHS+G1 group showed a significant reduction in lung coefficient and lung histopathological score [lung coefficient (mg/g): 3.9±0.1 vs. 4.6±0.3, lung histopathological score: 4.2±0.2 vs. 6.9±0.2, both P < 0.05]. HE staining revealed reduced severity of lung tissue fluid extravasation, inflammatory infiltration, decreased hemorrhage, and less severe alveolar structural damage. Serum levels of TNF-α, IL-1β, MDA, and Fe²⁺ were significantly reduced [TNF-α (ng/L): 44.3±0.2 vs. 64.6±0.3, IL-1β (ng/L): 69.3±0.4 vs. 97.8±0.2, MDA (nmol/L): 2.8±0.3 vs. 3.6±0.5, Fe²⁺ (nmol/L): 0.021±0.004 vs. 0.028±0.004, all P < 0.05]. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue (fluorescence intensity: 35.53±2.41 vs. 16.45±0.31, P < 0.05). RT-PCR and Western blotting showed significantly increased mRNA and protein expression of GPX4, FPN1, and FTH1 in lung tissue [mRNA expression: GPX4 mRNA (2^-ΔΔCt): 0.44±0.05 vs. 0.09±0.01, FPN1 mRNA (2^-ΔΔCt): 0.77±0.17 vs. 0.42±0.14, FTH1 mRNA (2^-ΔΔCt): 0.75±0.04 vs. 0.58±0.01; protein expression: GPX4/β-actin: 0.96±0.11 vs. 0.24±0.04, FPN1/β-actin: 1.26±0.21 vs. 0.44±0.14, FTH1/β-actin: 0.27±0.12 vs. 0.15±0.07; all P < 0.05]. However, there were no statistically significant differences in any of the above indicators between the EHS+DMSO group and the EHS group. CONCLUSION Activation of GPER can attenuate EHS-related lung injury in mice, and its mechanism may be related to the activation of the GPX4 signaling pathway and inhibition of ferroptosis.
Animals ; Mice, Inbred C57BL ; Male ; Mice ; Heat Stroke/metabolism* ; Receptors, G-Protein-Coupled ; Ferroptosis ; Receptors, Estrogen ; Acute Lung Injury/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-1beta/metabolism* ; Lung Injury ; Lung/metabolism*

OBJECTIVE: To investigate the distribution characteristics of polymorphonuclear neutrophil (PMN) in the lungs during the early stage of severe burns and the mechanism of neutrophil elastase (NE) promoting lung injury. METHODS: 6-8-week-old male C57BL/6J mice were selected for the experiments. A 30% total body surface area (TBSA) III degree burn mouse model was established (severe burn group); the Sham-injury group was treated with 37 centigrade water. In the sodium sivelestat intervention group (SV intervention group), NE competitive inhibitor, sivelestat, 100 mg/kg, was injected via tail vein immediately after injury, while other groups received an equal volume of saline. Ten mice were harvested from each group to observe survival for 72 hours. Respiratory function tests were tested at 0 (immediate), 3, 6, 12, and 24 hours after molding. hematoxylin-eosin (HE) and immunohistochemical staining were used to observe lung tissue structure, inflammatory changes and PMN infiltration. The PMN absolute count in mice lung tissue was detected buy flow cytometry. At 6, 12, and 24 hours after molding, PMN counts and the concentration of NE [enzyme linked immunosorbent assay (ELISA)] in peripheral blood plasma, lung tissue, and bronchoalveolar lavage fluid (BALF) were detected. RESULTS: (1) HE staining results showed that compared with the Sham-injury group, the lungs of mice in the severe burn group showed inflammatory changes and PMN infiltration, with more significant changes at 6 hours. Immunohistochemistry results also confirmed that the expression of NE protein released from PMN significantly increased after 6 hours of severe burn injury [(3.79±0.62)% vs. (0.18±0.05)%, t = 11.56, P < 0.01]. (2) Compared with the Sham-injury group, the number of PMN and the concentration of NE in the peripheral blood and lung tissues in the severe burn group were significantly increased (F values were 13.709, 55.350 and 29.890, 13.286, respectively, all P < 0.01), peaking at 6 hours [plasma PMN count (×10⁹/L): 2.92±1.01 vs. 0.92±0.29, lung tissue PMN absolute count (cells): 48 788.03±11 833.91 vs. 1 516.72±415.35, plasma NE (ng/L): 24 522.71±3 842.92 vs. 7 009.34±4 067.86, lung tissue NE (ng/L): 262 189.04±9 695.13 vs. 65 026.03± 16 016.31, all P < 0.01]. The number of PMN in the lung of severely burned mice was highly correlated with NE concentration (r = 0.892, P < 0.001). There was no significantly difference in the PMN absolute count in the BALF of mice between the Sham-injury group and severe burn group (F = 1.403, P > 0.05). The Sham-injury group and severe burn group contained a small amount of NE in the BALF, and the concentration of NE in the BALF of the severely burned 6 hours and 12 hours groups were significantly higher than those of the Sham-injury group (ng/L: 328.58±158.10, 415.30±240.89 vs. 61.95±15.80, both P < 0.05). (3) Kaplan-Meier survival curve showed that the 72-hour survival rate of mice in the SV intervention group was significantly higher than that in the severe burn group (100% vs. 10%, Log-Rank test: χ² = 19.12, P < 0.001). (4) Compared with the Sham-injury group, all lung function indices of the severe burn group decreased significantly. All lung function indices of SV intervention group improved gradually over time, which were significantly better than those of the severe burn group. (5) Compared with the Sham-injury group, the PMN absolute count in lung tissue and the concentration of NE in plasma and lung tissue were significantly higher in the SV intervention group (F values were 46.709, 3.535, 32.701, respectively, all P < 0.05), with a peak at 6 hours. Compared with the severe burn group, the SV intervention group had a higher PMN absolute count in lung tissue (cells: 8 870.80±7 013.89 vs. 25 974.92±22 240.8, P < 0.05), and higher plasma and lung tissue NE concentrations (ng/L: 14 955.94±3 944.41 vs. 21 972.75±4 573.05, 81 956.87±38 658.35 vs. 168 182.30±83 513.91, both P < 0.01) were significantly decreased. CONCLUSIONS In the early stage of severe burns, there is a significant infiltration of PMN into the lungs. The NE promotes lung injury in the early stage of severe burn, and improve lung injury by inhibiting the action of NE.
Animals ; Burns/metabolism* ; Leukocyte Elastase/metabolism* ; Male ; Mice, Inbred C57BL ; Mice ; Neutrophils/metabolism* ; Lung/metabolism* ; Disease Models, Animal ; Neutrophil Infiltration ; Lung Injury/metabolism* ; Glycine/analogs & derivatives* ; Sulfonamides