Objective To investigate the protective effects of endotoxin pretreatment on lung injury of rats with endotoxemia. Methods The rat model of acute endotoxemia was established by injecting lipopolysaccharide (LPS) intraperitoneally. Seventy-two male Wistar rats were randomly divided into three groups, ie. a saline control group (N, n=24) , a LPS-treated group (L, n=24) , and a LPS pretreated group ( P, n=24) . Each group was divided into 2 h, 4 h, 6 h, and 12 h subgroups. The rats in group P were firstly administered with introperitoneal injection of 0.25 mg/kg LPS. After 24 hours, they were subjected to the injection of 0.5 mg/kg LPS. The rats in group N and L received injection of equivalent amount of saline. After 72 hours, the rats in group L and P were challenged with intravenous injection of 10 mg/kg LPS, otherwise saline in group N. Six rats were killed at 2, 4, 6 and 12 hours respectively after injection of LPS in group L and P. The lungs were removed for detecting intercellular adhesion molecule-1 ( ICAM-1) , superoxide dismutase ( SOD) , and malondialdehyde (MDA) . Meanwhile the level of tumor necrosis factoralpha ( TNF-α) in serum was measured, and the pathological changes of lung were also examined. Results The contents of ICAM-1, MDA and TNF-α in the LPS-treated 4 h group were 75.07 ±0. 53, ( 3.93 ± 0.42) μmol/g, and (478.62 ±45.58) pg/mL respectively, significantly higher than those in the saline control group. The endotoxin pretreatment reduced the above indexes to 42.40 ±0.44, ( 2.89 ±0.49) μmol / g and ( 376.76 ±43.67) pg/mL respectively (Plt;0.05) . The content of SOD in the LPS-treated 4 h group was ( 6.26 ±0.31) U/mg, significantly lower than that in the saline control group. The endotoxin pretreatment increased SOD to ( 8.79 ±0.35) U/mg. Conclusion Endotoxin pretreatment can suppress the progress of lung injury in rats with endotoxemia and protect the lung tissue by down-regulating the inflammatory response and oxygen free radical production.
Objective To determine if mesenchymal stem cells ( MSCs) could be reconstructed as a vehicle for angiopoietin-1 ( Ang1) gene therapy in lung injury. Methods MSCs were obtained from adult male inbred mice and cultured to passage four. The cells were identified by fluorescence-activated cell sorting ( FACS) analysis and cell differentiation detection. Lentiviral vectors contained GFP and Ang1 gene were conducted in 293T cells through three plasmids co-transfection method. Then MSCs were transduced with Ang1 gene efficiently through lentiviral vectors. The mRNA expression of Ang1 in MSCs was detected by RT-PCR before and after transfection. Also fluorescence from MSCs was detected by fluorescence microscope every day after transfection. Two hours after LPS inhalation, mice were infused via jugular veinwith normal saline ( NS group) , lentiviral vector carrying Ang1 ( Ang1 group) , lentiviral vector carrying GFP ( MSCs group) , and lentiviral vector carrying Ang1 /GFP ( MSCs-Ang1 group) , respectively. Kaplan-Meier survival analysis was performed to compare the effects of MSCs-Ang1 on survival. And ectogenic MSCs origined lung cells were investigated in receipt mice. Results After passaged and purification,MSCs were confirmed to have the potential of differentiation. The lentiviral vectors carrying Ang1 and GFP were also identified. After transfection, the mRNA expression of Ang1 in MSCs was enhanced. Through the fluorescence microscope,MSCs get the most green fluorescence expression five days after the transfection when MOI was 20. Kaplan-Meier survival analysis showed that MSCs-Ang1 infusion had improved survival rates of lung injury rats compared with the control, but it did not reach statistical significance ( P = 0. 066) . Cells expressing GFP in lung tissues can be observed after MSCs were transplanted in vivo. Conclusions MSCs expressing Ang1 high can be constructed through lentiviral vector transfer, and MSCs-origined cells can be detected in receipt lungs after transplantation. So MSCs may serve as a vehicle for gene therapy in lung injury.
ObjectiveTo discuss the risk factors of acute respiratory distress syndrome (ARDS) in patients with severe pneumonia.MethodsData of 80 patients with severe pneumonia admitted in our ICU were analyzed retrospectively, and they were divided into two groups according to development of ARDS, which was defined according to the Berlin new definition. The age, gender, weight, Acute Physiology and Chronic Health EvaluationⅡscore, lactate, PSI score and LIPS score, etc. were collected. Statistical significance results were evaluated by multivariate logistic regression analysis after univariate analysis. Receiver operating characteristic (ROC) curve was plotted to analyze the predictive value of the parameter for ARDS after severe pneumonia.ResultsForty patients with severe pneumonia progressed to ARDS, there were 4 moderate cases and 36 severe cases according to diagnostic criteria. Univariate analysis showed that procalcitonin (t=4.08, P<0.001), PSI score (t=10.67, P<0.001), LIPS score (t=5.14, P<0.001), shock (χ2=11.11, P<0.001), albumin level (t=3.34, P=0.001) were related to ARDS. Multivariate logistic regression analysis showed that LIPS ［odds ratio (OR) 0.226, 95%CI=4.62-5.53, P=0.013］ and PSI (OR=0.854, 95%CI=132.2-145.5, P=0.014) were independent risk factors for ARDS. The predictive value of LIPS and PSI in ARDS occurrence was significant. The area under ROC curve (AUC) of LIPS was 0.901, the cut-off value was 7.2, when LIPS ≥7.2, the sensitivity and specificity were both 85.0%. AUC of PSI was 0.947, the cut-off value was 150.5, when PSI score ≥150.5, the sensitivity and specificity were 87.5% and 90.0% respectively.ConclusionsPSI and LIPS are independent risk factors of ARDS in patients with severe pneumonia, which may be references for guiding clinicians to make an early diagnosis and treatment plan.
Objective To explore the role of chronic ethanol ingestion in pulmonary fibrosis. Methods Twenty SD rats were randomly divided into a control group (n=10) and an ethanol group ( n=10) , and fed with quantitative non-ethanol and ethanol Lieber-DeCarli liquid diet every day respectively. All rats were sacrificed after 8 weeks. The morphological changes and collagen deposition of lung tissue were observed under light microscope by HE and Masson staining. Levels of glutathione (GSH) and hydroxyproline (HYP) in lung tissues were measured by colorimetric method. The content of connective tissue growth factor (CTGF) in lung tissue was detected by ELISA. Results Compared with the control group, varied degrees of alveolar and alveolar septal infiltration of inflammatory cells can be shown in the ethanol group, and also some alveolar wall damage or collapse.Masson staining showed that the ethanol group has more significant deposition of collagen fibers in alveolar interstitumthan the control group. The content of GSH in rat lung tissue reduced, but the contents of HYP and CTGF increased in the ethanol group compared with the control group [ GSH( mg/g) :0.08±0.04 vs. 0.22±0.14, HYP(mg/g) : 0.57±0.15 vs. 0.40 ± 0.09, CTGF(ng/mL) :306.57±46.86 vs. 134.02±79.82, Plt;0.05] . Conclusions Lieber-DeCarli ethanol liquid diet can establish a rat model of chronic ethanol ingestion. Lung injury and pulmonary fibrosis in rats can be induced by chronic ethanol ingestion. Ethanol may be one of the causes of the pulmonary fibrosis.
The contents of lipid peroxides(LPO)and vitamin E(V.E)and some functional index and histologic changes in the lungs from the the rabbit models of acute cholangitis of severe type(ACST)were measured dynamically.The results revealed that the V.E content decreased strikingly from 6 hours and the LPO level increased progressivelg from 12 hours in the lungs.Simultanuosly,the congestion and neutrophil infiltreation in the lung mesenchyme,and the endothelial cell damage and thrombosis in the lung blood capillaries had been observed.These suggest that acute lung injury induced by ACST is referable to the lipid peroxidation damage to the lung blood capillaries which is due to increased LPO and decreased antioxidants including V.E.
Objective To explore the migration and differentiation of bone marrow mesenchymal stem cells（MSCs） in lung . Methods MSCs were harvested from a male Wister rat. Sixty female Wister rats were randomly divided into four groups. The pulmonary fibrosis model was established by intratracheal instillation of bleomycin in group A-D. Immediately and 7 days after bleomycin administration respectively，the rats in group B and C received infusion with 5-bromodeoxynridine （BrdU） labeled MSCs via tail vein. And the rats in group D were infused MSCs without BrdU labeling serving as a negative control. The sry gene of Y chromosome was detected by polymerase chain reaction （PCR）. Double immunofluorescence staining was used to detected BrdU and surfactant associated protein-C （SP-C） expression in lung tissue，fresh bone marrow，and the 5th generation MSCs. Reverse transcriptipon-PCR was used to detect the expressions of SP-C mRNA and AQP-5 mRNA. Results The sry gene was detected in bleomycin induced lung injury tissues of the rats after MSCs infusion immediately and on the 7th day The MSCs in lung tissue could transformed into cells with ACEⅡ morphological features and molecular phenotype. The transformation rate was higher in the rats received MSCs infusion immediately than the rats received on 7th day. The 5th generation MSCs and fresh bone marrow expressed SP-C mRNA，without AQP-5 mRNA and SP-C expression. Conclusions Exogenous MSCs can be transplanted into injured lung tissues and transform into AECⅡ，especially in early stage of lung injury. The differentiation potential of MSCs can be activated in injury micro-environment.
ObjectiveTo explore the effects of inhibition of paxillin phosphorylation on ventilation associated lung injury. MethodsSixty healthy male SD rats were randomly divided into four groups, namely a control group, a protective ventilation group, a high tidal volume ventilation group, and an inhibitor group. The rats in the control group received only tracheotomy and breathe naturally. The rats in the protective ventilation group received protective ventilation for 2 hours. The rats in the high tidal volume ventilation group and the inhibitor group received high tidal volume ventilation for 2 hours. The rats in the inhibitor group additionally received intraperitoneal injection of tyrosine protein kinase inhibitor PP2 before ventilation. All rats were sacrificed and the specimens of lung tissue were collected. The pathological changes of lungs were observed under light microscope and estimated by the diffuse alveolar damage (DAD) score system. The activity of myeloperoxidase (MPO) and the lungs wet/dry (W/D) weight ratio were measured. The expression of tumor necrosis factor-α(TNF-α) in BALF was detected by ELISA. Evans blue (EB) method was used to detect the pulmonary vascular permeability. The expression levels of phosphorylated paxillin (p-paxillin) and paxillin in lung tissue were measured by Western blot. Apoptosis in situ was detected by TUNEL. ResultsThere were significant differences in the W/D ratio, the EB extravasation, DAD score, the MPO activity and the TNF-αexpression in BALF between the high tidal volume ventilation group and the inhibitor group (P < 0.05). The apoptosis rate of each group was sorted from high to low as the high tidal volume ventilation group, the inhibitor group, the protective ventilation group, and the control group. The expression level of p-paxillin was the highest in the high tidal volume ventilation group which was significantly different from other groups (all P < 0.05). There was no significant difference in the expression of paxillin in the protective ventilation group, the high tidal volume ventilation group and the inhibitor group (P > 0.05). ConclusionInhibition of paxillin phosphorylation can significantly alleviate mechanical ventilation associated lung injury.
ObjectiveTo summarize the changes and interaction of the cytokine in severe acute pancreatitis associated lung injury. MethodsThe published literatures at domestic and aboard in recent years about severe acute pancreatitis associated lung injury were collected and reviewed. ResultsThe cytokines had a chain effect, and influenced each other when severe acute pancreatitis with lung injury attacked. ConclusionsRelated cytokines play important roles in severe acute pancreatitis associated lung injury. Researching the related cytokines will contribute to the diagnosis and treatment for severe acute pancreatitis with lung injury.