Upregulation of PGC-1α expression by pioglitazone mediates prevention of sepsis-induced acute lung injury

Abstract The imbalance between pro-inflammatory M1 and anti-inflammatory M2 macrophages plays a critical role in the pathogenesis of sepsis-induced acute lung injury (ALI). Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) may modulate macrophage polarization toward the M2 phenotype by altering mitochondrial activity. This study aimed to investigate the role of the PGC-1α agonist pioglitazone (PGZ) in modulating sepsis-induced ALI. A mouse model of sepsis-induced ALI was established using cecal ligation and puncture (CLP). An in vitro model was created by stimulating MH-S cells with lipopolysaccharide (LPS). qRT-PCR was used to measure mRNA levels of M1 markers iNOS and MHC-II and M2 markers Arg1 and CD206 to evaluate macrophage polarization. Western blotting detected expression of peroxisome proliferator-activated receptor gamma (PPARγ) PGC-1α, and mitochondrial biogenesis proteins NRF1, NRF2, and mtTFA. To assess mitochondrial content and function, reactive oxygen species levels were detected by dihydroethidium staining, and mitochondrial DNA copy number was measured by qRT-PCR. In the CLP-induced ALI mouse model, lung tissues exhibited reduced PGC-1α expression. PGZ treatment rescued PGC-1α expression and alleviated lung injury, as evidenced by decreased lung wet-to-dry weight ratio, pro-inflammatory cytokine secretion (tumor necrosis factor-α, interleukin-1β, interleukin-6), and enhanced M2 macrophage polarization. Mechanistic investigations revealed that PGZ activated the PPARγ/PGC-1α/mitochondrial protection pathway to prevent sepsis-induced ALI by inhibiting M1 macrophage polarization. These results may provide new insights and evidence for developing PGZ as a potential ALI therapy.

Edema pulmonar por reexpansión. Reporte de Caso / Pulmonary edema due to re-expansion. Case Report

Introducción. El edema pulmonar por reexpansión es una complicación poco frecuente, secundaria a una rápida reexpansión pulmonar posterior al drenaje por toracentesis o toracostomía cerrada. Al día de hoy, se ha descrito una incidencia menor al 1 % tras toracostomía cerrada, con mayor prevalencia en la segunda y tercera década de la vida. Su mecanismo fisiopatológico exacto es desconocido; se ha planteado un proceso multifactorial de daño intersticial pulmonar asociado con un desequilibrio de las fuerzas hidrostáticas. Caso clínico. Presentamos el caso de un paciente que desarrolló edema pulmonar por reexpansión posterior a toracostomía cerrada. Se hizo una revisión de la literatura sobre esta complicación. Resultados. Aunque la clínica sugiere el diagnóstico, la secuencia de imágenes desempeña un papel fundamental. En la mayoría de los casos suele ser autolimitado, por lo que su manejo es principalmente de soporte; sin embargo, se han reportado tasas de mortalidad que alcanzan hasta el 20 %, por tanto, es importante conocer los factores de riesgo y las medidas preventivas. Conclusión. El edema pulmonar de reexpansión posterior a toracostomía es una complicación rara en los casos con neumotórax, aunque es una complicación que se puede presentar en la práctica diaria, por lo cual debe tenerse en mente para poder hacer el diagnóstico y un manejo adecuado.

Introduction. Re-expansion pulmonary edema is a rare complication secondary to rapid pulmonary re-expansion after drainage by thoracentesis and/or closed thoracostomy. As of today, an incidence of less than 1% has been described after closed thoracostomy, with a higher prevalence in the second and third decades of life. Its exact pathophysiological mechanism is unknown; a multifactorial process of lung interstitial damage associated with an imbalance of hydrostatic forces has been proposed. Clinical case. We present the case of a patient who developed pulmonary edema due to re-expansion after closed thoracostomy, conducting a review of the literature on this complication. Results. Although the clinic suggests the diagnosis, the sequence of images plays a fundamental role. In most cases, it tends to be a self-limited disease, so its management is mainly supportive. However, mortality rates of up to 20% have been recorded. Therefore, it is important to identify patients with major risk factors and initiate preventive measures in these patients. Conclusions. Re-expansion pulmonary edema after thoracostomy is a rare complication in cases with pneumothorax; however, it is a complication that can occur in daily practice. Therefore, it must be kept in mind to be able to make the diagnosis and an adequate management.

Protective Effect of Zingiberis Rhizoma Recens on LPS-induced Acute Lung Injury in Mice Through TLR4/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo explore the protective effect and mechanism of Zingiberis Rhizoma Recens alcohol extract on lipopolysaccharide （LPS）-induced acute lung injury in mice. MethodBalb/c mice were randomly divided into normal group， model group， dexamethasone group， and low- and high-dose Zingiberis Rhizoma Recens groups. Mice in the normal group were instilled with normal saline through the nose， and the other groups were instilled with normal saline containing LPS （50 μg）. After 30 minutes of modeling， the dexamethasone group was gavaged with 5 mg·kg-1 of dexamethasone acetate solution， the low- and high-dose Zingiberis Rhizoma Recens groups were gavaged with different doses of （7， 14 g·kg-1） of Zingiberis Rhizoma Recens alcohol extract， and the normal group and the model group were gavaged with the same volume of water. After 24 hours of modeling， the total number of white blood cells in bronchoalceolar lavage fluid （BALF） was detected by cell counter， and the levels of the inflammatory factors including tumor necrosis factor （TNF）-α， interleukin （IL）-1β， IL-6， and superoxide dismutase （SOD）， and myeloperoxidase （MPO） was detected by enzyme-linked immunosorbent assay （ELISA）. Haematoxylin-eosin （HE） staining method was used to observe the pathological changes of lung tissue in each group， and the Western blot was used to detect the protein expression of nuclear transcription factor （NF）-κB p65， phosphorylation （p）-NF-κB p65， and Toll-like receptor 4 （TLR4） in lung tissue. ResultCompared with the normal group， the white blood cell count in BALF and the levels of TNF-α， IL-1β， IL-6， and MPO in the model group was increased （P<0.01）， and the level of SOD was decreased （P<0.05）. Pathological damage of lung tissue was obvious， and the protein expression of NF-κB p65， p-NF-κB p65， and TLR4 in lung tissue was increased （P<0.01）. Compared with the model group， the white blood cell count in BALF and the levels of TNF-α， IL-1β， IL-6， and MPO in the treatment group was decreased （P<0.05，P<0.01）， and the level of SOD was increased （P<0.05，P<0.01）. Pathological damage of lung tissue was alleviated， and the protein expression of NF-κB p65， p-NF-κB p65， and TLR4 in lung tissue was decreased （P<0.01）. ConclusionZingiberis Rhizoma Recens alcohol extract may play a protective role in LPS-induced acute lung injury in mice by inhibiting the TLR4/NF-κB signaling pathway.

Xuebijing improves inflammation and pyroptosis of acute lung injury by up-regulating miR-181d-5p-mediated SPP1 inactivation

Abstract Background Xuebijing (XBJ) is widely applied in the treatment of Acute Lung Injury (ALI). This study focused on the potential mechanism of XBJ in Lipopolysaccharide (LPS)-induced ALI. Methods The rat ALI model was established by injection of LPS (10 mg/kg) and pretreated with XBJ (4 mL/kg) three days before LPS injection. BEAS-2B cell line was stimulated with LPS (1 μg/mL) and ATP (5 mM) to induce pyroptosis, and XBJ (2 g/L) was pretreated 24h before induction. The improvement effects of XBJ on pulmonary edema, morphological changes, and apoptosis in ALI lung tissue were evaluated by lung wet/dry weight ratio, HE-staining, and TUNEL staining. Inflammatory cytokines in lung tissue and cell supernatant were determined by ELISA. pyroptosis was detected by flow cytometry. Meanwhile, the expressions of miR-181d-5p, SPP1, p-p65, NLRP3, ASC, caspase-1, p20, and GSDMD-N in tissues and cells were assessed by RT-qPCR and immunoblotting. The relationship between miR-181d-5p and SPP1 in experimental inflammation was reported by dual luciferase assay. Results XBJ could improve inflammation and pyroptosis of ALI by inhibiting contents of inflammatory cytokines, and levels of inflammation- and pyroptosis-related proteins. Mechanistically, XBJ could up-regulate miR-181d-5p and inhibit SPP1 in ALI. miR-181d-5p can target the regulation of SPP1. Depressing miR-181d-5p compensated for the ameliorative effect of XBJ on ALI, and overexpressing SPP1 suppressed the attenuating effect of XBJ on LPS-induced inflammation and pyroptosis. Conclusion XBJ can regulate the miR-181d-5p/SPP1 axis to improve inflammatory response and pyroptosis in ALI.

Lesión pulmonar aguda producida por transfusión (TRALI): Reporte de caso

Introducción: La lesión pulmonar aguda (TRALI) y la sobrecarga circulatoria (TACO) son las principales causas de morbilidad y mortalidad relacionadas con la transfusión. La TRALI se presenta durante o después de las transfusiones de plasma y sus derivados, o por inmunoglobulinas en alta concentración intravenosa; se asocia a procesos sépticos, cirugías y transfusiones masivas. La TACO es la exacerbación de manifestaciones respiratorias en las primeras 6 horas postransfusión. Reporte caso: Paciente de sexo masculino de 38 días de vida, ingresó al servicio de urgencias con un cuadro clínico de 8 días de evolución, caracterizado por dificultad respiratoria dado por retracciones subcostales y aleteo nasal sin otro síntoma asociado, con antecedentes de importancia de prematuridad y bajo peso al nacer. El reporte de hemograma arrojó cifras compatibles con anemia severa, por lo que requirió transfusión de glóbulos rojos empaquetados desleucocitados. El paciente presentó un cuadro respiratorio alterado en un periodo menor a 6 horas, por lo que se descartaron causas infecciosas y finalmente se consideró cuadro compatible con TRALI. Conclusiones: Se debe considerar una lesión pulmonar aguda relacionada con una transfusión de sangre si se produce una insuficiencia respiratoria aguda durante o inmediatamente después de la infusión de hemoderivados que contienen plasma.

Introduction: Acute lung injury (TRALI) and circulatory overload (TACO) are the main causes of transfusion-related morbidity and mortality. TRALI occurs during or after transfusions of plasma or its derivatives, or by immunoglobulins in high intravenous concentration; it is associated with septic processes, surgeries, and massive transfusions. TACO is the exacerbation of respiratory manifestations in the first 6 hours post transfusion. Case report: A 38-day-old male was admitted to the emergency department with clinical symptoms experienced over the course of 8 days and characterized by respiratory distress due to subcostal retractions and nasal flaring with no other associated symptoms. Important antecedents included prematurity and low birth weight. The hemogram report showed figures compatible with anemia, which benefited from transfusion of packed red blood cells without leukocytes. In a period of less than 6 hours, the patient presented altered respiratory symptoms, practitioners ruled out infectious causes and finally considered clinical signs compatible with TRALI. Conclusion: Acute lung injury related to blood transfusion should be considered if acute respiratory failure occurs during or immediately after infusion of plasma-containing blood products.

Ischemic Postconditioning Attenuates Myocardial Ischemia-Reperfusion-Induced Acute Lung Injury by Regulating Endoplasmic Reticulum Stress-Mediated Apoptosis

ABSTRACT Objective: To explore the effect of ischemic postconditioning on myocardial ischemia-reperfusion-induced acute lung injury (ALI). Methods: Forty adult male C57BL/6 mice were randomly divided into sham operation group (SO group), myocardial ischemia-reperfusion group (IR group), ischemic preconditioning group (IPRE group) and ischemic postconditioning group (IPOST group) (10 mice in each group). Anterior descending coronary artery was blocked for 60 min and then reperfused for 15 min to induce myocardial IR. For the IPRE group, 3 consecutive cycles of 5 min of occlusion and 5 minutes of reperfusion of the coronary arteries were performed before ischemia. For the IPOST group, 3 consecutive cycles of 5 min reperfusion and 5 minutes of occlusion of the coronary arteries were performed before reperfusion. Pathological changes of lung tissue, lung wet-to-dry (W/D) weight ratio, inflammatory factors, oxidative stress indicators, apoptosis of lung cells and endoplasmic reticulum stress (ERS) protein were used to evaluate lung injury. Results: After myocardial IR, lung injury worsened significantly, manifested by alveolar congestion, hemorrhage, structural destruction of alveolar septal thickening, and interstitial neutrophil infiltration. In addition, lung W/D ratio was increased, plasma inflammatory factors, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-17A, were increased, malondialdehyde (MDA) activity of lung tissue was increased, and superoxide dismutase (SOD) activity was decreased after myocardial IR. It was accompanied by the increased protein expression levels of ERS-related protein glucose regulatory protein 78 (GRP78), CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), and caspase-12, and the increased apoptotic indices of lung tissues. Conclusion: IPOST can effectively improve myocardial IR-induced ALI by inhibiting ERS-induced apoptosis of alveolar epithelial cells.

Construction of a risk warning model for acute lung injury caused by Staphylococcus aureus infection / 中华传染病杂志

Objective:To investigate the risk factors of acute lung injury (ALI) caused by Staphylococcus aureus infection, and to construct a risk warning model. Methods:Patients with Staphylococcus aureus infection confirmed by sputum or blood culture admitted to the Affiliated Hospital of Jiangnan University from January 1, 2020 to May 10, 2022 were enrolled and divided into ALI group and non-ALI group. The age, smoking status, C-reactive protein (CRP), procalcitonin (PCT), neutrophil-to-lymphocyte ratio (NLR), albumin, oxygenation index and other clinical data were compared between the two groups. Univariate analysis was performed by using independent sample t test and chi-square test. Binary logistic regression analysis was used to screen the independent risk factors of ALI caused by Staphylococcus aureus infection, and a risk warning model was constructed. The receiver operator characteristic (ROC) curve was used to evaluate the predictive ability of the model. Results:There were 96 cases of Staphylococcus aureus infection, including 68 cases (70.8%) in ALI group, of which 41 cases (60.3%) were positive in sputum culture and 27 cases (39.7%) were positive in blood culture. Compared with the non-ALI group, the proportion of patients aged ≥60 years in ALI group was lower (58.8%(40/68) vs 64.3%(18/28)), the proportion of smoking was higher (58.8%(40/68) vs 35.7%(10/28)), and the differences were both statistically significant ( χ2=0.76 and 0.03, respectively, both P<0.05). The levels of CRP, PCT and NLR in the ALI group were all higher than those in non-ALI group, while oxygenation index and albumin level were both lower, and the differences were all statistically significant ( t=-5.28, -3.46, -9.87, 12.83 and 3.08, respectively, all P<0.05). Binary logistic regression analysis showed that CRP (odds ratio ( OR)=1.973, 95% confidence interval (95% CI) 0.956 to 2.989), PCT ( OR=3.734, 95% CI 1.014 to 13.746), NLR ( OR=1.152, 95% CI 1.058 to 2.254) and albumin ( OR=1.527, 95% CI 1.110 to 2.102) were independent risk factors for ALI caused by Staphylococcus aureus infection. The areas under the ROC curve of CRP, PCT, NLR, albumin and the risk warning model constructed from the combination of four risk factors were 0.69, 0.81, 0.83, 0.78 and 0.93, respectively. The sensitivities were 65.14%, 89.91%, 84.40%, 56.88% and 98.17%, respectively. The specificities were 62.37%, 60.22%, 65.59%, 80.64% and 93.55%, respectively. The accuracy of the effectiveness test of the risk warning model was 84.97%. Conclusions:CRP, PCT, NLR and albumin are the independent risk factors for ALI caused by Staphylococcus aureus infection. The risk warning model based on the above factors has a good early warning effect on ALI caused by Staphylococcus aureus infection.

Protective effect of barium chloride pretreatment on lung in mice with acute respiratory distress syndrome / 中华危重病急救医学

Objective:To explore whether barium chloride (BaCl 2) preconditioning has the protective effect on lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) model in mice and the possible mechanism. Methods:Sixty 8-12 week old healthy C57BL/6 male mice were randomly divided into control group, ARDS model group and BaCl 2 pretreatment group, with 20 mice in each group. The BaCl 2 pretreatment group was continuously injected with BaCl 2 (4 mg/kg through the tail vein) for 3 days before ARDS model establishment. ARDS model was established by intratracheally injecting (3 mg/kg) LPS. The control group was intratracheally given the same volume of 0.9% normal saline. On 24th hour after ARDS model establishment, some mice were sacrificed for obtaining fresh lung tissue. And the right lower lobe of the lung was separated for observing the pathological changes of lung tissue while the left lung tissue was used to measure the wet/dry weight ratio (W/D) of the lung. Some mice were sacrificed for observing pulmonary microvascular permeability at 2nd hours after injecting Evans blue (EB) through tail vein. The left mice were killed for alveolar lavage to measure the levels of tumor necrosis factor-α (TNF-α) via enzyme linked immunosorbent assay (ELISA). Results:Comparing with the control group, ARDS model group showed typical ARDS pathological changes, which included the increased W/D ratio (4.951±0.161 vs. 3.449±0.299, P < 0.01) and the content of EB in the lung tissue (μg/g: 0.130±0.027 vs. 0.085±0.011, P < 0.01), the damaged alveolar wall structure, lung congestion and exudates in the alveoli, as well as amounts of inflammatory cells. The pathological score of lung injury (10.33±1.15 vs. 1.67±0.58) and the level of TNF-α in BALF (ng/L: 900.85±247.80 vs. 68.21±5.79) were significantly increased in the ARDS model group (both P < 0.01). Comparing with the ARDS model group, the lung W/D ratio (4.620±0.125 vs. 4.951±0.161) and the EB content in the lung tissue (μg/g: 0.108±0.011 vs. 0.130±0.027) of BaCl 2 pretreatment group were significantly reduced (both P < 0.01). And the damaged pulmonary structural BaCl 2 pretreatment group were significantly alleviated. In addition, the pulmonary pathological score (5.00±1.00 vs. 10.33±1.15) and the level of TNF-α in BALF (ng/L: 169.16±73.33 vs. 900.85±247.80) were significantly decreased (both P < 0.01). Conclusion:Barium chloride pretreatment can improve the lung histopathological changes of ARDS model mice induced by LPS by reducing the permeability of pulmonary capillaries and local inflammatory reaction.Barium chloride has the protective effect against LPS attack in mice model of ARDS.

Effect of SIRT1 regulating Nrf2/HO-1 signaling pathway on sepsis-induced acute lung injury / 中华危重病急救医学

Objective:To investigate whether silence information regulator 1 (SIRT1) could regulate nuclear factor E2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) signaling pathway and its role in acute lung injury (ALI) in sepsis rats.Methods:Twenty-four male Sprague-Dawley (SD) rats were randomly divided into sham operation group (Sham group), cecal ligation and puncture (CLP) induced sepsis group (CLP group), sepsis+SIRT1 specific agonist group (CLP+SRT1720 group,10 mg/kg SRT1720 was intraperitoneally injected 2 hours before CLP), sepsis+SIRT1 specific inhibitor group (CLP+EX527 group, 10 mg/kg EX527 was intraperitoneally injected 2 hours before CLP), with 6 rats in each group. The rats were killed 24 hours after modeling and their lung tissues were taken for pathological score (Smith score), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukins (IL-6, IL-1β), and SIRT1, Nrf2 and HO-1 mRNA and protein expression were detected.Results:The lung tissue of the CLP group mice was severely damaged, the alveolar interval was widened and a large number of inflammatory cells infiltrated, and there was visible pulmonary capillary hyperemia. The Smith score, the levels of TNF-α, IL-6, IL-1β, MDA and 8-OHdG were significantly increased, the levels of SOD, GSH, SIRT1, Nrf2 and HO-1 were significantly decreased in CLP group. After using SIRT1 specific agonist, the lung injury in CLP+SRT1720 group was significantly alleviated compared with that in CLP group, Smith score and lung tissue TNF-α, IL-6, and IL-1β levels were significantly decreased [Smith score: 2.83±0.75 vs. 5.67±0.52, TNF-α (ng/L): 36.78±5.36 vs. 66.99±5.44, IL-6 (ng/L): 23.97±3.76 vs. 45.70±4.16, IL-1β (ng/L): 16.76±1.39 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content increased [SOD (kU/g): 115.88±3.31 vs. 101.65±1.09, GSH (μmol/g): 8.42±0.81 vs. 5.74±0.46, both P < 0.05], MDA and 8-OHdG contents decreased [MDA (μmol/g): 5.24±0.33 vs. 9.86±0.66, 8-OHdG (ng/L): 405.76±8.54 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were increased [SIRT1 mRNA (2 -ΔΔCT): 1.49±0.15 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 1.19±0.08 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 1.80±0.41 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 1.03±0.06 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 1.14±0.10 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 1.01±0.11 vs. 0.73±0.03, all P < 0.05]. The lung injury in CLP+EX527 group was more severe than that in CLP group, Smith score and lung tissue TNF-α, IL-6, IL-1β levels were significantly increased [Smith score: 8.00±0.89 vs. 5.67±0.52, TNF-α (ng/L): 87.15±4.23 vs. 66.99±5.44, IL-6 (ng/L): 66.79±2.93 vs. 45.70±4.16, IL-1β (ng/L): 58.99±2.12 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content decreased [SOD (kU/g): 72.84±3.85 vs. 101.65±1.09, GSH (μmol/g): 3.30±0.67 vs. 5.74±0.46, both P < 0.05], the contents of MDA and 8-OHdG were increased [MDA (μmol/g): 14.14±0.70 vs. 9.86±0.66, 8-OHdG (ng/L): 927.66±11.47 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were decreased [SIRT1 mRNA (2 -ΔΔCT): 0.40±0.07 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 0.48±0.07 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 0.27±0.14 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 0.20±0.05 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 0.45±0.01 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 0.36±0.08 vs. 0.73±0.03, all P < 0.05]. Conclusions:In the rat model of ALI induced by sepsis, SIRT1 can regulate the activation of Nrf2/HO-1 signaling pathway, upregulate the expression of downstream antioxidant enzymes, reduce oxidative stress injury, and then alleviate the ALI induced by sepsis in rats.

MicroRNA21-5p alleviates hyperoxia-induced acute lung injury in rats through activating phosphatidylinositol 3 kinase/serine-threonine protein kinase signaling pathway by regulating type Ⅱ alveolar epithelial cell apoptosis / 中华危重病急救医学

Objective:To investigate whether microRNA-21-5p (miR-21-5p) alleviates hyperoxia-induced acute lung injury (HALI) through activating the phosphatidylinositol 3 kinase/serine-threonine protein kinase (PI3K/Akt) signaling pathway by regulating apoptosis of type Ⅱ alveolar epithelial cell (AECⅡ).Methods:Seventy-two male Sprague-Dawley (SD) rats were divided into normozone-controlled group, HALI group, PI3K/Akt signaling pathway inhibitor LY294002+HALI group (LY+HALI group), miR-21-5p overexpression+LY294002+HALI group (miR-21-5p+LY+HALI group), miR-21-5p overexpression+HALI group (miR-21-5p+HALI group), and dimethyl sulfoxide (DMSO)+HALI group by random number table method with 12 rats in each group. Animal models of HALI were prepared using 95% concentrations of oxygen. The animals in the normozone-controlled group were fed normally under normoxia. Transfection of lung tissue by miR-21-5p adeno-associated viral vector AAV6-miR-21-5p was performed by instillation of 200 μL titer (1×10 12 TU/mL) through a tracheal catheter 3 weeks prior to modeling. DMSO and LY294002 were administered via the tail vein at 0.3 mg/kg 1 hour before modeling. After 48 hours of modeling, carotid artery blood was collected to detect oxygenation index (OI) and respiratory index (RI), and real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to detect miR-21-5p expression. Lung tissue was collected, and the levels of inflammatory factors including tumor necrosis factor-α (TNF-α) and interleukins (IL-6, IL-1β) were measured by enzyme-linked immunosorbent assay (ELISA), and the ratio of pulmonary wet/dry weight (W/D) was determined, and the pathological changes of lung histopathology were observed under the light microscopy after hematoxylin-eosin (HE) staining. Each group was purified AECⅡ cells from 6 rats, the apoptosis rate was detected by flow cytometry, and the expression levels of phosphatase and tensin homologous gene (PTEN), and proteins from the PI3K/Akt signaling pathway were detected by Western blotting. Results:Compared with the normozone-controlled group, alveolar septal thickening and massive inflammatory cell infiltration were found after hyperoxia exposure, RI, inflammatory factors, lung W/D ratio, pathological score, AECⅡ cells early apoptosis rate, PTEN protein expression and phosphorylation level of Akt were increased, while OI and miR-21-5p expression were decreased, indicating the successful preparation of the model. After pretreatment, LY294002 could aggravate the pathological injury of lung tissue in HALI rats, RI, inflammatory factors and lung W/D ratio were further increased, and OI was further reduced compared with HALI group. At the same time, it could promote the AECⅡ cell apoptosis, further up-regulate the expression of PTEN, and reduce the phosphorylation of Akt. However, miR-21-5p pretreatment could negatively regulate PTEN, activate PI3K/Akt signal pathway, inhibit AECⅡ cell apoptosis, and reduce HALI, which was shown by the decreased level of inflammatory factors in miR-21-5p+LY+HALI group compared with LY+HALI group [TNF-α (μg/L): 100.33±3.48 vs. 116.55±2.53, IL-6 (ng/L): 141.06±3.70 vs. 161.31±3.59, IL-1β (μg/L): 90.82±3.69 vs. 112.23±2.87, all P < 0.05], RI, lung injury pathology score, lung W/D ratio, and AECⅡ cell early apoptosis rate were significantly decreased [RI: 0.81±0.02 vs. 1.05±0.07, pathology score: 0.304±0.008 vs. 0.359±0.007, lung W/D ratio: 5.29±0.03 vs. 5.52±0.08, apoptosis rate: (27.20±2.34)% vs. (34.17±1.49)%, all P < 0.05], OI and expressions of miR-21-5p were significantly increased [OI (mmHg, 1 mmHg≈0.133 kPa): 266.71±2.75 vs. 230.12±4.04, miR-21-5p (2 -ΔΔCt): 2.21±0.13 vs. 0.33±0.03, both P < 0.05], and PTEN protein expression in AECⅡ cell was significantly reduced (PTEN/GAPDH: 0.50±0.06 vs. 0.93±0.06, P < 0.05), and phosphorylation level of Akt was significantly increased [phosphorylated Akt (p-Akt) protein (p-Akt/GAPDH): 0.86±0.05 vs. 0.56±0.06, P < 0.05]. Conclusion:miR-21-5p attenuates HALI by inhibiting AECⅡ cell apoptosis, possibly through negative regulation of PTEN to activate PI3K/Akt signaling pathway.

Effect of FTY720 on transfusion-related acute lung injury: a preliminary investigation / 中国输血杂志

【Objective】 To investigate the effects and mechanisms of different doses of fingolimod (FTY720) on non-antibody-mediated transfusion-related acute lung injury (TRALI). 【Methods】 A TRALI mouse model was constructed using lipopolysaccharide (LPS) pre-stimulation and platelets (Plt) of different storage days for second strike. The success of the modeling was determined by protein concentration in lung tissue homogenates, myeloperoxidase (MPo) activity, lung wet/dry weight ratio (W/D ratio), lung tissue damage score and pathological sections. Ceramide and sphingosine-1-phosphate (S1P) contents in platelets of different storage days were detected. FTY720 was administered 1 h after LPS injection to investigate the role of FTY720 in TRALI. The expression levels of vascular endothelial cadherin (VE-cadherin) and zonula occludens-1 (ZO-1) were analyzed by WB. 【Results】 Mice infused with stored 5-day Plt (d5Plt group) exhibited typical signs of TRALI, and the differences in lung tissue homogenate protein concentration (6 546.38±409.50) μg/mL, MPO activity (49.38±4.43) U/L, W/D ratio 4.79±0.21, and lung tissue damage score 7.24±0.38 from the rest of the groups were statistically significant (P<0.05). With the increase of platelet storage time, the ceramide content gradually increased and S1P content gradually decreased, and the ratio of the two was imbalanced. d5Plt showed statistically significant differences (P<0.01) in ceramide content (58.37±5.69) μmol/L and S1P content (149.81±4.86) nmol/L from the rest of the groups. After preventive administration of FTY720, 1 mg/kg FTY720 had no significant effect on TRALI mice, whose lung tissue homogenate protein concentration (6 170.26±545.50) μg/mL, MPO activity (45.97±4.79) U/L, W/D ratio 4.88±0.25, and lung tissue damage score 7.92±0.65 were significantly higher than those of the normal and LPS control groups (P<0.01). The low-dose (0.5, 0.2, and 0.1 mg/kg) FTY720 group alleviated lung injury, and its protein concentration, MPO activity, W/D ratio, and lung tissue injury score were significantly lower than those of the d5Plt group (P<0.05). Pathological sections also showed similar results. In terms of endothelial intercellular junction protein expression, the VE-cadherin expression levels in the 1 mg/kg FTY720 group were significantly lower than those in the normal and LPS control groups (P<0.05), and the VE-cadherin and ZO-1 expression levels in the low-dose (0.5, 0.2, and 0.1 mg/kg) FTY720 group were significantly higher than those in the d5Plt group (P<0.05), which tended to be normalized. 【Conclusion】 In this study, a TRALI mouse model was successfully established by one strike of LPS and two strikes of d5Plt. Low doses of FTY720 (0.5, 0.2, 0.1 mg/kg) were protective against TRALI, while high doses of FTY720 (1 mg/kg) may aggravate the symptoms of TRALI. This protective effect may be somewhat dependent on the expression of VE-cadherin and ZO-1.

Study on transfusion-related acute lung injury caused by HLA-Ⅱ antibody / 中国输血杂志

【Objective】 To explore the risk factors of transfusion-related acute lung injury (TRALI). 【Methods】 The clinical symptoms, signs, imaging examinations, and laboratory test results of two patients with TRALI after blood transfusion were retrospectively analyzed, and human leukocyte antigen (HLA) genotyping of the patient and HLA antibodies typing of the plasma donors were performed. 【Results】 The clinical manifestations and laboratory parameters of two patients were consistent with those of TRALI after blood transfusion. After timely clinical respiratory support treatment, all patients were improved. Blood donors produced high titers of HLA-Ⅱ antibodies after pregnancy, including antibodies that specifically recognize the patient′s HLA antigen. 【Conclusion】 Two patients developed TRALI after platelet transfusion from a female blood donor, which was caused by HLA-Ⅱ antibodies.

Study on Mechanism of Linggan Wuwei Jiangxintang in Treating Acute Lung Injury / 中国实验方剂学杂志

ObjectiveTo explore the action mechanism of Linggan Wuwei Jiangxintang on the treatment of lipopolysaccharide （LPS）-induced acute lung injury （ALI） in mice. MethodTraditional Chinese Medicine Systems Pharmacology Database and Analysis Platform （TCMSP）， GeneCards， DisGeNET， and Herb databases were combined with clinical data from Gene Expression Omnibus （GEO） to screen the key targets of Linggan Wuwei Jiangxintang in the treatment of ALI. The protein-protein interaction （PPI） network was constructed to screen the core targets， and gene ontology （GO） and Kyoto encyclopedia of genes and genomes （KEGG） pathway enrichment analyses were performed. The mouse ALI model was established by LPS induction to verify the effect and key targets of Linggan Wuwei Jiangxintang on the treatment of ALI. The expression levels of Toll-like receptor 4 （TLR4）， nuclear transcription factor-κB p65 （NF-κB p65）， and phosphorylated NF-κB p65 （NF-κB p-p65） in lung tissue were detected by Western blot. ResultThe analysis showed that the treatment of ALI with Linggan Wuwei Jiangxintang was related to 10 core targets such as interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， and JUN， involving TNF signaling pathway， Toll-like receptor signaling pathway， NF-κB signaling pathway， etc. The animal experimental results show that Linggan Wuwei Jiangxintang can reduce lung injury， improve the pathological state of ALI mice， significantly reduce the expression of TNF-α and IL-6 in serum， increase the activity of total superoxide dismutase （T-SOD） and catalase （CAT） in lung tissue， and reduce the expression levels of JUN， TLR4， NF-κB p65， and NF-κB p-p65 proteins in lung tissue. ConclusionLinggan Wuwei Jiangxintang can inhibit LPS-induced inflammation and oxidative damage in ALI mice， and its mechanism may be related to the inhibition of TLR4/NF-κB signaling pathway and the reduction of inflammatory factors such as TNF-α and IL-6.

Evaluation of Animal Models of Acute Lung Injury Caused by Non-physical Factors Based on Data Mining / 中国实验方剂学杂志

ObjectiveTo study the characteristics of animal models of acute lung injury caused by non-physical factors， so as to provide a reference for the standardization of the preparation of such animal models and lay a foundation for the research on the pathogenesis and the diagnosis and treatment of acute lung injury. MethodThe articles about the animal experiments of acute lung injury published in the last decade were retrieved from China National Knowledge Infrastructure （CNKI）， Wanfang， SinoMed， VIP， and PubMed with the theme terms of "acute lung injury" and "animal model". The animal species， drugs used in modeling， modeling period， methods used in molding， model standards， and model evaluation indicators were summarized， and Excel was used for the frequency analysis. ResultA total of 338 articles were included in this study. The results of the frequency analysis showed that SD rats/C57BL/6 mice were mainly used to establish the animal models of acute lung injury. Male mice were mostly used for modeling， and the commonly used modeling agent was lipopolysaccharides （LPS）. In most cases， the modeling lasted for 6 h after drug administration. Hematoxylin-eosin staining was mainly used for the observation of histological changes in the lungs， which were taken as the criteria for modeling. The established models were mainly evaluated based on lung dry/wet weight ratio， lung index， morphological changes in the lung tissue， myeloperoxidase （MPO）， superoxide dismutase （SOD）， and levels of inflammatory cytokines in the serum and bronchoalveolar lavage fluid （BALF）. ConclusionThe models of acute lung injury were mostly prepared by intraperitoneal injection of LPS （5 mg·kg-1） in SD rats and tracheal instillation of LPS （5 mg·kg-1） in C57BL/6 mice， which were praised for the simple operation， high success rate， and consistent with the pathogenesis of acute lung injury. This study provides a reference for the basic research on acute lung injury by animal experiments.

Protective effect of luteolin on acute lung injury induced by extracorporeal circulation and its mechanism / 中国胸心血管外科临床杂志

@#Objective    To investigate the protective effect of atomized inhalation of nano-luteolin preparation on acute lung injury caused by extracorporeal circulation, and to explore the anti-inflammatory mechanism of luteolin, so as to provide study basis for clinical application. Methods    Thirty male SD rats aged 5-6 weeks and weighting 160-190 g, were randomly divided into a preoperative baseline (BL) group, arteriovenous partial diversion (ECC) group, luteolin atomization pretreatment for 1 h group, 2 h group, and 3 h group by random number method, with 6 rats in each group. In the BL group, lung tissue samples were collected directly without any treatment. The ECC group received mechanical ventilation, and the whole body was heparinized after the jugular arteriovenous intubation. The flow was transferred for 30 minutes, followed by observation for 60 minutes, then lung tissue samples were collected. Subjects in the 1 h, 2 h and 3 h groups were placed in a small animal atomizer 1 h, 2 h and 3 h before flow transfer respectively, and the subsequent operation was the same as that in the ECC group. The inflammatory level of lung tissue was detected to evaluate the degree of pathological injury of lung tissue. Western blotting (WB) was used to detect the contents of p65, IKKα, IKKβ and IKKγ in the cytoplasm of lung tissue samples of each group. Results    Compared with the ECC group, the levels of IL-6 and TNF-α in lung tissues and the degree of pathological injury in the 1 h, 2 h and 3 h groups decreased, and the difference between the 3 h group and the ECC group was statistically different (P<0.05). WB results showed that compared with the ECC group, the levels of p65 in lung tissue of the 1 h, 2 h and 3 h groups decreased; the levels of IKKβ in the lung tissue increased in the 1 h, 2 h and 3 h groups, and the difference of the 3 h group was statistically different from the ECC group (P<0.05). Conclusion    Luteolin has a protective effect on acute lung injury induced by ECC, and atomization 3 h in advance has the best protective effect on lung. The mechanism plays a protective role in ECC-induced acute lung injury, may be through inhibition of IKKβ phosphorylation, thereby inhibiting the classical NF-κB signaling pathway.

Clearance effect of regulation of serine/threonine protein kinase-1 signaling pathway by insulin on pulmonary edema in mice with acute lung injury / 中国生物制品学杂志

@#Objective To investigate the mechanism of insulin alleviating pulmonary edema in mice with acute lung injury(ALI) by serine/threonine protein kinase-1(SGK1).Methods 32 male adult C3H/HeN mice were randomly divided into control group(only pumped with the same amount of normal saline as the treatment group),ALI group(continuously pumped with the same amount of normal saline as the treatment group after modeling),treatment group [continuously pumped with 0.1 U/(kg·h) of insulin through jugular vein after establishing ALI model] and SGK1 siRNA group[continuously pumped with 0.1 U/(kg·h) of insulin and given SGK1 siRNA(75 μg SGK1 siRNA diluted in 100 μL saline) simultaneously after establishing ALI model] with 8 mice in each group.After 8 h,the mice were killed for arterial blood gas analysis(1 h after establishment of the model) and the changes of plasma glucose levels were detected(0,1,4and 8 h);The bronchoalveolar lavage fluid(BALF) was collected to detect the content of total protein,and the alveolar epithelial permeability and lung water content were measured;The pathological changes of lung tissue and apoptosis of lung epithelial cells were observed;The protein expressions of alveolar epithelial sodium channel(ENaC) and α_1-Na~+,K~+-ATPase and the phosphorylation level of SGK1 were determined by Western blot.Results There was no significant difference in plasma glucose level of ALI and treatment group at 0,1,4 and 8 h after insulin infusion(t=1.330 0,0.986 0,0.565 7 and 0.724 3,P=0.204 7,0.340 7,0.580 6 and 0.480 8,respectively).Compared with ALI group,the partial pressure of oxygen in arterial blood in treatment group increased significantly(t=6.026,P <0.000 1),while the BALF protein content,alveolar epithelial permeability,lung water content and lung epithelial cells apoptosis decreased significantly(t=7.39,5.286,5.651 and 3.312,P <0.000 1,=0.000 4,=0.000 2 and=0.007 8,respectively),and the expression of α-ENaC and α_1-Na~+,K~+-ATPase and the phosphorylation level of SGK1 in lung tissue significantly increased(t=26,18.67 and 8.547,P <0.000 1,<0.000 1 and=0.000 1,respectively);Compared with the treatment group,the BALF protein content,alveolar epithelial permeability,lung water content and lung epithelial cells apoptosis increased significantly in SGK1 siRNA group(t=5.964,3.449,3.148 and 3.520,P=0.000 2,0.006 2,0.010 4 and0.016 9,respectively),while α-ENaC and α_1-Na~+,K~+-ATPase protein expression and SGK1 phosphorylation level decreased significantly(t=13,9.874 and 7.741,P <0.000 1,<0.000 1 and=0.001 5,respectively).Conclusion Exogenous insulin can alleviate the pulmonary edema in ALI mice,which might be mediated via up-regulation of the expressions of α-ENaC and α_1-Na~+,K~+-ATPase by SGK1.

Role of PIAS-regulated SUMOylation of PPARγ in endogenous protective mechanism against endotoxin-induced acute lung injury in mice / 中华麻醉学杂志

Objective:To evaluate the role of small ubiquitin-associated modifier (SUMO) E3 ligase (PIAS)-regulated SUMOylation of peroxisome proliferator-activated receptor γ (PPARγ) in the endogenous protective mechanism against endotoxin-induced acute lung injury (ALI) in mice.Methods:Experiment Ⅰ Twenty-four clean-grade wild type male C57BL/6 mice, aged 6-8 weeks, weighing 18-22 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (C group), ALI group, ALI+ PPARγ inducer TZD group (ALI+ T group) and ALI+ TZD+ SUMOylation inhibitor anacardic acid group (ALI+ T+ A group). Lipopolysaccharide (LPS) 15 mg/kg was injected into the tail vein to develop the ALI model. In ALI+ T+ A group, anacardic acid 5 mg/kg was intraperitoneally injected at 1 h before LPS administration. In ALI+ T group and ALI+ T+ A group, TZD 50 mg/kg was intraperitoneally injected at 30 min before LPS administration. The mice were sacrificed at 12 h after LPS administration, and the lung tissues were obtained to examine the pathological changes which were scored and to determine the wet/dry (W/D) weight ratio, and expression of PIAS1, PIAS2, PIAS3 and PIASy protein and mRNA (by Western blot or polymerase chain reaction). Experiment Ⅱ Mouse alveolar macrophages (MH-S cells) were cultured in vitro and divided into 4 groups ( n=5 each) using a random number table method: control group (C group), LPS group, LPS+ PIAS2 siRNA group (L+ P group) and LPS+ Con siRNA group (L+ C group). Cells were routinely cultured in group C. Cells were stimulated with 10 μg/ml LPS to develop the model of endotoxin challenge. PIAS2 siRNA 50 nmol/L and Con siRNA 50 nmol/L were transfected at 48 h before LPS was added in L+ P group and L+ C group, respectively. The cells were collected at 24 h of incubation with LPS to determine the cell viability, levels of M1 and M2 alveolar macrophages (by flow cytometry), expression of PIAS2 and PPARγ (by Western blot), co-expression of PPARγ-SUMO1 (by immunoprecipitation) and expression of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) mRNA (by polymerase chain reaction). The ratio of M1/M2 was calculated. Results:Experiment Ⅰ Compared with C group, the lung injury scores and W/D ratio were significantly increased, and the expression of PIAS2 protein and mRNA was up-regulated in the other three groups ( P<0.05). Compared with ALI group, the lung injury scores and W/D ratio were significantly decreased, and the expression of PIAS2 protein and mRNA was up-regulated in ALI+ T group and ALI+ T+ A group ( P<0.05). Compared with ALI+ T group, the lung injury scores and W/D ratio were significantly increased, and the expression of PIAS2 protein and mRNA was down-regulated in ALI+ T+ A group ( P<0.05). There was no significant difference in the expression of PIAS1, PIAS3 and PIASy protein and mRNA in lung tissues among the four groups ( P>0.05). Experiment Ⅱ Compared with C group, the cell viability was significantly decreased, the expression of PPARγ and co-expression of PPARγ-SUMO1 was up-regulated, the levels of M1 and M2 macrophages and M1/M2 ratio were increased, the expression of TNF-α mRNA was up-regulated, and the expression of IL-10 mRNA was down-regulated in the other three groups, and PIAS2 expression was significantly up-regulated in L group and L+ C group ( P<0.05). Compared with L group, the cell viability was significantly decreased, the expression of PIAS2 and PPARγ and PPARγ-SUMO1 co-expression were down-regulated, the M1 macrophage level and M1/M2 ratio were increased, TNF-α mRNA expression was up-regulated, and the expression of IL-10 mRNA was down-regulated in L+ P group ( P<0.05), and no significant change was found in the parameters mentioned above in L+ C group ( P>0.05). Compared with L+ C group, the cell viability was significantly decreased, the expression of PIAS2 and PPARγ and co-expression of PPARγ-SUMO1 were down-regulated, the level of M1 alveolar macrophages and M1/M2 ratio were increased, the expression of TNF-α mRNA was down-regulated, and the expression of IL-10 mRNA was up-regulated in L+ P group ( P<0.05). Conclusions:PIAS2-regulated SUMOylation of PPARγ is the endogenous protective mechanism against endotoxin-induced ALI in mice, which may be related to inhibition of macrophage polarization into M1 type and alleviation of inflammatory responses.

Role of aryl hydrocarbon receptor in down-regulation of Clara cell secretory protein expression during endotoxin-induced lung injury in rats / 中华麻醉学杂志

Objective:To evaluate the role of aryl hydrocarbon receptor (AhR) in the down-regulation of Clara cell secretory protein (CCSP) expression during endotoxin-induced lung injury in rats.Methods:Twenty-four clean-grade healthy male Sprague-Dawley rats, aged 8 weeks, weighing 200-250 g, were divided into 4 groups ( n=6 each) using a random number table method: normal control group (group C), acute lung injury (ALI) group, ALI+ AhR antagonist group, and ALI+ vehicle group. Lipopolysaccharide(LPS) 1 mg/kg was intratracheally instilled to develop the model of lung injury, while the equal volume of normal saline was given instead in group C. At 2 h before LPS injection, AhR antagonist 6, 2′, 4′-trimethoxyflavone solution 5 mg/kg (diluted to 1 ml in dimethyl sulfoxide solution) was intraperitoneally injected in ALI+ AhR antagonist group, while dimethyl sulfoxide solution 1 ml was given in ALI+ vehicle group. The rats were sacrificed under anesthesia at 48 h after LPS administration. The left lung was lavaged and the broncho-alveolar lavage fluid (BALF) was collected for determination of the concentrations of CCSP by enzyme-linked immunosorbent assay, and the expression of CCSP in the bronchial epithelium in right lung tissues was determined by immunohistochemistry. Results:Compared with group C, the expression of CCSP in the bronchial epithelium was significantly down-regulated, and the concentrations of CCSP in BALF were decreased in the other three groups ( P<0.05 or 0.01). Compared with ALI group and ALI+ vehicle group, the histopathological injury was significantly reduced, the expression of CCSP in the bronchial epithelium was up-regulated, and the concentrations of CCSP in BALF were increased in ALI+ AhR antagonist group ( P<0.01). Conclusions:AhR partially mediates the down-regulation of CCSP expression during endotoxin-induced lung injury in rats.

Role of α7nAChR in penehyclidine hydrochloride-induced reduction of endotoxin-induced acute lung injury in mice / 中华麻醉学杂志

Objective:To evaluate the role of α7 nicotinic acetylcholine receptor (α7nAChR) in penehyclidine hydrochloride-induced reduction of endotoxin-induced acute lung injury (ALI) in mice.Methods:Forty SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 18-25 g, were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), ALI group, penehyclidine hydrochloride group (PHC group), and α7nAChR inhibitor MLA group (MLA group). ALI was induced by intraperitoneal injection of lipopolysaccharide 15 mg/kg in anesthetized animals, while normal saline was given instead in group C. In PHC group, penehyclidine hydrochloride 2 mg/kg was intraperitoneally injected at 30 min before developing the model. MLA 10 mg/kg was intraperitoneally injected at 10 min before administration of penehyclidine hydrochloride in MLA group. Mice were sacrificed at 6 h after lipopolysaccharide administration, and lung tissues were collected for microscopic examination of the pathological changes (by HE staining) and for determination of the wet/dry weight ratio (W/D ratio), content of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-10 (by enzyme-linked immunosorbent assay) and expression of α7nAChR (by Western blot). Results:Compared with C group, the W/D ratio and contents of TNF-α and IL-1β were significantly increased, the content of IL-10 was decreased, and the expression of α7nAChR was up-regulated in ALI, PHC and MLA groups ( P<0.05). Compared with ALI group, the W/D ratio and contents of TNF-α and IL-1β were significantly decreased, the content of IL-10 was increased, and the expression of α7nAChR was up-regulated in PHC group ( P<0.05). Compared with PHC group, the W/D ratio and contents of TNF-α and IL-1β were significantly increased, the content of IL-10 was decreased, and the expression of α7nAChR was down-regulated in MLA group ( P<0.05). Compared with ALI group, the pathological changes of lung tissues were significantly mitigated in PHC group, while this effect of PHC was partially reversed by α7nAChR inhibitor MLA. Conclusions:α7nAChR is involved in penehyclidine hydrochloride-induced reduction of endotoxin-induced ALI in mice.

Relationship between SIRT1 and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis / 中华麻醉学杂志

Objective:To evaluate the relationship between silent information regulator 1 (SIRT1) and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis.Methods:One hundred and fifty-two SPF-grade male C57BL/6J mice, aged 8 weeks, weighing 23-27 g, were divided into 4 groups ( n=38 each) using a random number table method: sham operation group (C group), sepsis group (S group), curcumin group (Cur group) and curcumin plus SIRT1 inhibitor EX527 group (CE group). Curcumin 200 mg/kg was administered by intragastric gavage every day in Cur group. Curcumin 200 mg/kg was administered by intragastric gavage every day and EX527 5 mg/kg was intraperitoneally injected in CE group. The equal volume of solvent dimethyl sulfoxide (DMSO) was given in C group and S group. Sepsis model was developed by cecal ligation and puncture (CLP) after 5 days of consecutive administration in anesthetized animals. Twenty mice in each group were randomly selected to observe the survival condition within 7 days after CLP. The bronchoalveolar lavage fluid (BALF) was collected at 24 h after developing the model to determine the concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6 and IL-18 (by enzyme-linked immunosorbent assay), and the lung tissues were obtained for microscopic examination of the pathological changes which were scored and for determination of wet-to-dry lung weight (W/D) ratio, contents of glutathione (GSH), malondialdehyde (MDA) and iron (by colorimetry), and expression of SIRT1, glutathione peroxidase 4 (GPX4) and Acyl-CoA synthetase long chain family member 4 (ACSL4) (by Western blot). Results:Compared with C group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH in lung tissues was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in S group ( P<0.05). Compared with S group, the 7-day survival rate after CLP was significantly increased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were decreased, the content of GSH was increased, the contents of MDA and iron were decreased, the expression of SIRT1 and GPX4 was up-regulated, and the expression of ACSL4 was down-regulated in Cur group ( P<0.05). Compared with Cur group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in CE group ( P<0.05). Conclusions:The mechanism by which curcumin attenuates acute lung injury may be related to activation of SIRT1 and further inhibition of ferroptosis in mice.