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OBJECTIVE@#To demonstrate the mechanism of mechanical ventilation (MV) induced endoplasmic reticulum stress (ERS) promoting mechanical ventilation-induced pulmonary fibrosis (MVPF), and to clarify the role of angiotensin receptor 1 (AT1R) during the process.@*METHODS@#The C57BL/6 mice were randomly divided into four groups: Sham group, MV group, AT1R-shRNA group and MV+AT1R-shRNA group, with 6 mice in each group. The MV group and MV+AT1R-shRNA group mechanically ventilated for 2 hours after endotracheal intubation to establish MVPF animal model (parameter settings: respiratory rate 70 times/minutes, tidal volume 20 mL/kg, inhated oxygen concentration 0.21). The Sham group and AT1R-shRNA group only underwent intubation after anesthesia and maintained spontaneous breathing. AT1R-shRNA group and MV+AT1R-shRNA group were airway injected with the adeno-associated virus one month before modeling to inhibit AT1R gene expression in lung tissue. The expressions of AT1R, ERS signature proteins [immunoglobulin heavy chain-binding protein (BIP), protein disulfide isomerase (PDI)], fibrosis signature proteins [collagen I (COL1A1), α-smooth muscle actin (α-SMA)] in lung tissues were detected by immunofluorescence and Western blotting. Hematoxylin-eosin (HE) staining was used to evaluate lung injury and Masson staining was used to evaluate pulmonary fibrosis.@*RESULTS@#Compared with the Sham group, the degree of pulmonary fibrosis and lung injury were more significant in the MV group. In the MV group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were increased (AT1R/β-actin: 1.40±0.02 vs. 1, BIP/β-actin: 2.79±0.07 vs. 1, PDI/β-actin: 2.07±0.02 vs. 1, COL1A1/α-Tubulin: 2.60±0.15 vs. 1, α-SMA/α-Tubulin: 2.80±0.25 vs. 1, all P < 0.01). The number of E-cad+/AT1R+ and E-cad+/BIP+ cells in lung tissue increased, and the fluorescence intensity of COL1A1 and α-SMA increased. Compared with the MV group, the degree of pulmonary fibrosis and lung injury were significantly relieved in the MV+AT1R-shRNA group. In the MV+AT1R-shRNA group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were decreased (AT1R/β-actin: 0.53±0.03 vs. 1.40±0.02, BIP/β-actin: 1.73±0.15 vs. 2.79±0.07, PDI/β-actin: 1.04±0.07 vs. 2.07±0.02, COL1A1/α-Tubulin: 1.29±0.11 vs. 2.60±0.15, α-SMA/α-Tubulin: 1.27±0.10 vs. 2.80±0.25, all P < 0.01). The number of E-cad+/AT1R+ and E-cad+/BIP+ cells in lung tissue decreased, and the fluorescence intensity of COL1A1 and α-SMA decreased. There was no statistically significant difference in the indicators between AT1R-shRNA group and Sham group.@*CONCLUSIONS@#MV up-regulate the expression of AT1R in alveolar epithelial cells, activate the AT1R pathway, induce ERS and promote the progression of MVPF.
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Mice , Animals , Pulmonary Fibrosis/chemically induced , Lung Injury , Respiration, Artificial/adverse effects , Actins/metabolism , Tubulin , Mice, Inbred C57BL , Endoplasmic Reticulum Stress , RNA, Small InterferingABSTRACT
Objective To evaluate the inhibitory effect of butyric acid (BA) as a histone deacetylase (HDAC) inhibitor on lipopolysaccharide (LPS)-induced pulmonary fibrosis and its mechanism. Methods Thirty C57/BL6 mice were randomly divided into three groups according to the random number method, namely control group (physiological saline was given intraperitoneally and by gavage), LPS challenge group (LPS-induced murine model of pulmonary fibrosis was reproduced with intraperitoneal injection of 10 mg/kg LPS), and BA preconditioning + LPS challenge group (10 mg/kg BA was given followed by intraperitoneal injection of 10 mg/kg LPS), with 10 mice in each group. Mice were sacrificed painlessly, and lung tissue samples were harvested at 2 weeks and 4 weeks respectively (five samples every group each time). HDAC activity was evaluated with fluorescence analysis kit. Protein expression of acetylated-histone H3 (Ace-H3), acetylated-histone H4 (Ace-H4) and thymocyte differentiation antigen 1 (Thy-1) were determined by Western Blot. The mRNA expression of Thy-1 was assessed by real-time reverse transcription- polymerase chain reaction (real-time RT-PCR). The degree of lung inflammation and fibrosis were microscopic detected after hematoxylin-eosin (HE) staining and Masson collagen staining. The deposition of lung collagen was detected by hydroxyproline content measurement kit. Results Compared to control group, the degree of lung inflammation and fibrosis was aggravated after LPS challenge, as manifested by increased hydroxyproline content (μg/mg, 2 weeks: 8.384±0.632 vs. 4.388±0.334, 4 weeks: 8.308±0.244 vs. 4.370±0.342, both P 0.05; 0.426±0.098 vs. 0.858±0.177 at 4 weeks, P 0.05; relative expression of Thy-1 protein (gray value): 0.725±0.284 vs. 1.249±0.297 at 2 weeks, 0.589±0.139 vs. 1.372±0.343 at 4 weeks, both P < 0.05]. Compared with LPS group, BA precondition could inhibit above processes, as manifested by decreased hydroxyproline content (μg/mg: 5.943±0.726 vs. 8.384±0.632 at 2 weeks, 4.938±0.209 vs. 8.308±0.244 at 4 weeks, both P < 0.01), decreased HDAC activity (μmol/L: 4.386±0.117 vs. 7.243±0.384 at 2 weeks, 4.863±0.096 vs. 6.479±0.202 at 4 weeks, both P < 0.01), increased Thy-1 mRNA expression at 2 weeks (2-ΔΔCt: 0.884±0.216 vs. 0.606±0.066, P < 0.05), increased acetylation degree of histone H4 and Thy-1 protein expression at 4 weeks [relative expression of Ace-H4 (gray value): 0.715±0.145 vs. 0.426±0.098, P < 0.05; relative protein expression of Thy-1 (gray value): 0.939±0.098 vs. 0.589±0.139, P < 0.01]. Conclusions LPS-induced pulmonary fibrosis was related with activation of HDAC, deacetylation of histone H3 and H4 and Thy-1 gene silencing. HDAC inhibitor BA could inhibit LPS-induced pulmonary fibrosis and Thy-1 gene silencing through inhibiting activation of HDAC and deacetylation of histone H4.
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Objective To evaluate the effect of lipopolysaccharide (LPS) on thymocyte differentiation antigen-1 (Thy-1) mRNA expression in mouse lung fibroblasts.Methods Primary cultured mouse lung fibroblasts were seeded in 96-well plates with the density of 1 × 104/ml.After being cultured for 48 h,the cells were randomly divided into 4 groups (n =3 each):PBS control group (group C),LPS 0.01 μg/ml group (group LPS0.01),LPS 0.10 μg/ml group (group LPS0.10),and LPS 1.00 μg/ml group (group LPS1.00).PBS was added to the 96-well plates in group C.LPS with the final concentrations of 0.01,0.10 and 1.00 μg/ml were added to the 96-well plates in groups LPS0.01,LPS0.10 and LPS1.00,respectively.After being incubated for 0,6,24,48 and 72 h (T0-4),the proliferation of the cells was measured by CCK-8 assay and Thy-1 mRNA expression was detected by real-time PCR.Results Compared with group C,the proliferation of the cells was significantly increased,while Thy-1 mRNA expression was down-regulated at T3,4 in groups LPS0.01,LPS0.10 and LPS1.00 (P ＜ 0.05).The proliferation of the cells was gradually increased,while Thy-1 mRNA expression was gradually down-regulated in groups LPS0.01,LPS0.10 and LPS1.00 at T3,4 (P ＜ 0.05).Conclusion LPS results in abnormal proliferation of mouse lung fibroblasts through down-regulating Thy-1 mRNA expression,indicating that endoxemia-induced pulmonary fibrosis is related to the down-regulation of Thy-1 mRNA expression in lung fibroblasts.
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ObjectiveThe study is to investigate the predictive values of dosimetric parameters and patient related factors in severe acute radiation pneumonitis (SARP) after concurrent chemoradiotherapy in non-small cell lung cancer (NSCLC).Methods In all,147 NSCLC patients treated with concurrent chemotherapy and 3DCRT between 2006 and 2010 was collected.Independent sample t test was used to compare parameter values between patients with SARP and those without SARP.Logistic regression was used to identify significant determined factor.Predictive value of each parameter was tested by ROC analysis.Pearson correlation was used to analyze correlations between parameters.Represent factors were identified by factor analysis.ResultsThe incidence of SARP was 9.5％ ( 14/147 ).The means lung dose (MLD),V20,V30,V40,and V50 ( x2 =4.87 -6.84,P =0.009 -0.025,respectively ) were determining factors for SARP.Our datasets shows that for SARP ＜5％,MLD,V20,V30,V40 and V50 should be ≤16.77 Gy,V20≤34.15％,.V30 ≤23.62％,.V40 ≤ 18.57％,V50 ≤ 13.02％.ROC analysis show that areas under MLD,V20,V30,V40 and V50 curves was corresponding to 0.678,0.661,0.667,0.677,and 0.651,respectively.In addition,the sensitivity and specificity of each parameter at cutoff values are:78.0％ and 48.1％ for MLD;42.9％ and 82.0％ for V2o ;78.6％ and 52.9％ for V30 ;71.4％ and 61.7％ for V40,and 57.1％ and 67.7％ for V50.Factor analysis suggest that we can choose 1 or 2 parameters from MLD,V20,or V30,and another from V40 or V50 for predicting.The incidence of SARP was greater in patients with tumorsin right lower lung than other locations ( 22.2％ vs 6.7％,x2 =6.19,P =0.0 2 3 ).Conclusions The MLD,V20,V30,V40 and V50 are determining factors for SARP.As predictive value of each parameter alone is relatively week,using two or more parameters to predict SARP is recommended.
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Objective To investigate the effect of lipopolysaccharide (LPS) on the activation of mouse lung fibroblasts. Methods Primary cultured mouse lung fibroblasts were incubated in 96 well plates and randomly divided into 2 groups: control group ( group C, n = 6) and LPS group ( n = 24). The fibroblasts were cultured for 72 h in group C. LPS 1 μg/ml was added and then the fibroblasts were incubated for 72 h in group LPS. The expression of type Ⅰ procollagen mRNA, α-smooth muscle actin (α-SMA) mRNA, Toll-like receptor 4 (TLR4)mRNA and integrin β1 mRNA was determined using real-time PCR at 3, 6, 24 and 72 h of incubation (6 wells at each time point). Results Compared with group C, there was no significant change in the expression of type Ⅰ procollagen mRNA, α-SMA mRNA, TLR4 mRNA and integrin β1 mRNA at 3, 6 and 24 h of incubation ( P ＞0.05), but the parameters mentioned above were significantly up-regulated at 72 h of incubation in group LPS ( P ＜ 0.05). Conclusion In the early acute lung injury, LPS leads to pulmonary fibrosis through activating lung fibroblasts directly, and also accelerates the activation of lung fibroblasts and promotes the process of pulmonary fibrosis through up-regulating the expression of TLR4 and integrin β1 in mice.
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The fluid status variate sharply in patients after operation. Appropriate fluid therapy is essential to reduce perioperative complications, shorten hospitalization days and improve prognosis of postoperative patients. In this article, we reviewed the relevant issues about fluid therapy strategy for postoperative patients such as the variation of body fluid in patients after operation, the assessment of fluid status, the establishment of the goal of fluid therapy and the selection of strategy or fluid for fluid therapy in patients after operation.