Altered surfactant protein A gene expression and protein homeostasis in rats with emphysematous changes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The decrease of surfactant protein (SP) secreted by the alveolar type II cell is one of the important causes of limiting air of pulmonary emphysema. However, the SP-A gene and protein changes in this disease are rarely studied. This study was undertaken to investigate alterations in SP-A gene activity and protein, and to explore their roles in the pathogenesis of emphysematous changes.</p><p><b>METHODS</b>Twenty Wistar rats were divided randomly into a normal control group (n = 10) and a cigarette smoking (CS) + lipopolysaccharide (LPS) group (n = 10). Ultra-structural changes were observed under an electron microscope. The number of cells positive for SP-A was measured by immunohistochemistry. The mRNA expression and protein level of SP-A in the lung tissues were determined by quantitative polymerase chain reaction (qPCR) and Western blot separately. The protein level of SP-A in lavage fluid was determined by Western blot.</p><p><b>RESULTS</b>The number of cells positive for SP-A of the CS + LPS group (0.35 +/- 0.03) was lower than that of the blank control group (0.72 +/- 0.06, P < 0.05). The level of SP-A in the lung tissues of rats in the CS + LPS group (0.2765 +/- 0.0890) was lower than that in the blank control group (0.6875 +/- 0.1578, P < 0.05). The level of SP-A in the lavage fluid of rats in the CS + LPS group (0.8567 +/- 0.1458) was lower than that in the blank control group (1.3541 +/- 0.2475, P < 0.05). The lung tissues of rats in the CS + LPS group showed an approximate increase (0.4-fold) in SP-A mRNA levels relative to beta-actin mRNA (P < 0.05).</p><p><b>CONCLUSIONS</b>The changes of SP-A may be related to emphysematous changes in the lung. And cigarette smoke and LPS alter lung SP-A gene activity and protein homeostasis.</p>

Protective effect of tanshinone II A on lipopolysaccharide-induced lung injury in rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To explore the protective effect of tanshinone II A on lipopolysaccharide (LPS)-induced lung injury in rats, and possible mechanism.</p><p><b>METHODS</b>LPS (O(111): B4) was used to produce a rat model of acute lung injury. Sprague-Dawley rats were randomly divided into 3 groups (8 in each group): the control group, the model group (ALI group), and the tanshinone II A treatment group. Expression of adhesion molecule CD18 on the surface of polymorphonuclear neutrophil (PMNCD18) in venous white blood cells (WBC), and changes in coagulation-anticoagulant indexes were measured 6 h after injection of LPS or normal saline. Changes in malondialdehyde (MDA) content, wet and dry weight (W/D) ratio and morphometry of pulmonary tissue as well as PMN sequestration in the lung were also measured.</p><p><b>RESULTS</b>(1) When compared with the control group, expression of PMNCD18 and MDA content were enhanced in the ALI group with a hypercoagulable state (all P<0.01) and an increased W/D ratio (P<0.05). Histopathological morphometry in the lung tissue showed higher PMN sequestration, wider alveolar septa; and lower alveolar volume density (V(V)) and alveolar surface density (S(V)), showing significant difference (P<0.01). (2) When compared with the ALI group, the expression of PMN-CD18, MDA content, and W/D ratio were all lower in Tanshinone II A treatment group (P<0.05) with ameliorated coagulation abnormality (P<0.01). Histopathological morphometry in the lung tissue showed a decrease in the PMN sequestration and the width of alveolar septa (both P<0.01), and an increase in the V(V) and S(V) (P<0.05, P<0.01).</p><p><b>CONCLUSION</b>Tan II A plays a protective role in LPS-induced lung injury in rats through improving hypercoagulating state, decreasing PMN-CD18 expression and alleviating migration, reducing lipid peroxidation and alleviating pathological changes.</p>

Effect of intramuscular injection of hepatocyte growth factor plasmid DNA with electroporation on bleomycin-induced lung fibrosis in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>So far, there is no efficient treatment for pulmonary fibrosis. The objective of this study was to determine whether intramuscular injection of the hepatocyte growth factor (HGF) plasmid DNA by in vivo electroporation could prevent bleomycin-induced pulmonary fibrosis in rats, and to investigate the possible mechanisms.</p><p><b>METHODS</b>Twenty male Wistar rats were randomly divided into four groups: control group (group C), model group (group M), early intervention group (group I) and late intervention group (group II). Groups M, I and II were intratracheally infused with bleomycin, then injected the plasmid pcDNA3.1-hHGF to group I on day 7, 14 and 21. Group II received the same treatment like Group I on day 14 and 21. All the rats were killed on day 28 after bleomycin injection. We detected Homo HGF expression in the rats with ELISA method and estimated the pathological fibrosis score of lung tissue using hematoxylin eosin (HE) and Massion staining. The mRNA expression of transforming growth factor-beta1 (TGF-beta1), cycloxygenase-2 (COX-2), and rat HGF in rat pulmonary parenchyma were evaluated by RT-PCR. Immunohistochemistry and Western blotting were performed to determine the protein expression of transforming TGF-beta1 and COX-2 in lung parenchyma.</p><p><b>RESULTS</b>The plasmid pcDNA3.1-hHGF could express hHGF in NIH3T3 cells and the hHGF protein is secreted into the culture medium. The expression of hHGF protein could be monitored in quadriceps muscle, plasma and lung in Groups I and II. Pulmonary fibrosis levels of Groups I and II were obviously lower than that of group M (P < 0.05). Expression of TGF-beta1 protein and mRNA in lung tissue was markedly decreased in Groups I and II compared with Group M (P < 0.05). The level of expression of HGF and COX-2 mRNA was higher in Groups I and II than in Group M (P < 0.05).</p><p><b>CONCLUSIONS</b>Injection of the plasmid pcDNA3.1-hHGF into skeletal muscle with electroporation has a potential role in the treatment of bleomycin-induced lung fibrosis. Exogenous HGF may inhibit the expression of TGF-beta1 and regulate the crosstalk between AECs and mesenchymal fibroblasts.</p>

Inhibitory effects of Salvia miltiorrhiza injection coordinated with dexamethasone on interleukin-13 and eotaxin expression in lung of asthmatic rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the molecular mechanism of inhibitory effect of Salvia miltiorrhiza Injection (SMI) coordinated with dexamethasone (DXM) on allergic airway inflammation in asthmatic rats.</p><p><b>METHODS</b>Forty SD rats were randomly divided into 5 groups equally: the normal group, the asthma model group, the DXM group, the SMI group and the DXM + SMI group, they were treated with correspondant herbal medicines. Pathologic changes of lung tissue were obseved with HE stain, count of WBC and eosinophil (Eos) in bronchoalveolar lavage fluid (BALF) were estimated and the expressions of interleukin-13 (IL-13) and Eotaxin in lung tissue were measured by RT-PCR and SP method of immunohistochemistry assay.</p><p><b>RESULTS</b>There was moderate inflammation in lung tissue in the SMI group, and mild inflammation in the DXM + SMI and the DXM group, which was similar to that in the normal group. Compared with the asthma model group, Eos and WBC count in BALF and the expression of IL-13 and Eotaxin in the lung tissue were significantly lower in the three treated groups (P < 0.05), particularly in the DXM + SMI group, showing a significant difference as compared with the other two groups (P < 0.05 or P < 0.01). Additionally, IL-13 expression was positively correlated with Eotaxin expression (r = 0.92, P < 0.01).</p><p><b>CONCLUSION</b>SMI could inhibit the expression of IL-13 and Eotaxin in the lung of asthmatic rats, showing inhibitory effects synergistic with DXM on airway inflammation.</p>

Effect of shenmai injection on L-type calcium channel of diaphragmatic muscle cells in rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Shenmai Injection (SMI) on L-type calcium channel of diaphragmatic muscle cells in rats.</p><p><b>METHODS</b>Single diaphragmatic muscle cell of rats was obtained by the acute enzyme isolation method and the standard whole-cell patch clamp technique was used to record the inward peak L-type calcium current (IPLC) and current-voltage relationship curve of diaphragmatic muscle cells of 7 rats, and to compare the effects of SMI in various concentrations on them.</p><p><b>RESULTS</b>When keeping the electric potential at -80 mV, stimulation frequency 0.5 Hz, clamp time 300 ms, stepped voltage 10 mV, and depolarized to +60 mV, 10 microliters/ml of SMI could only cause the mean IPLC of rat's diaphragmatic muscle cells increased from -6.9 +/- 0.6 pA/pF to -7.5 +/- 0.7 pA/pF, the amplification being (9.2 +/- 2.8)%, comparison between those of pre-treatment and post-treatment showed insignificant difference. But when the concentration of SMI increased to 50 microliters/ml and 100 microliters/ml, the mean IPLC increased to -8.4 +/- 0.6 pA/pF and -9.2 +/- 0.6 pA/pF, respectively, and the amplification was (22.4 +/- 1.7)% and (34.6 +/- 4.6)% respectively, showing significant difference to that of pre-treatment (P < 0.05). However, SMI showed no significant effect on maximal activation potential and reversal potential.</p><p><b>CONCLUSION</b>SMI can activate the calcium channel of diaphragmatic muscle cells in rats, increase the influx of Ca2+, so as to strengthen the contraction of diaphragmatic muscle, which may be one of the ionic channel mechanisms of SMI in treating diaphragmatic muscle fatigue in clinical practice.</p>