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A mass was detected in the middle lobe of the right lung of a 58-year-old female. The patient did not present any symptoms and was a nonsmoker. Diagnostic evaluation revealed squamous metaplasia in the middle lobe of the right lung. During surgery, a tumor was identified, which was diagnosed as a lymphoepithelioma-like carcinoma (LELC). LELCs have been mainly reported in the Asian population and are associated with the Epstein-Barr virus (EBVs), while they are not associated with smoking. Squamous metaplasia, which is the basis of squamous cell carcinoma, differs from LELC in the therapeutic methods used and the prognostic evaluation. Squamous metaplasia requires regular follow-up in out-patient clinics, while pulmonary LELC is treated by surgery and chemotherapy. Therefore, distinguishing between LELCs and other nonmalignant or premalignant conditions is essential.

After birth, the respiratory tract adapts to recurrent exposures to pathogens, allergens, and toxicants by inducing the complex innate and acquired immune systems required for pulmonary homeostasis. In this study, we show that Foxa2, expressed selectively in the respiratory epithelium, plays a critical role in regulating genetic programs influencing Th2 cell-mediated pulmonary inflammation. Deletion of the Foxa2 gene, encoding a winged helix/forkhead box transcription factor that is selectively expressed in respiratory epithelial cells, caused spontaneous pulmonary eosinophilic inflammation and goblet cell metaplasia. Loss of Foxa2 induced the recruitment and activation of myeloid dendritic cells and Th2 cells in the lung, causing increased production of Th2 cytokines and chemokines. Loss of Foxa2-induced expression of genes regulating Th2 cell-mediated inflammation and goblet cell differentiation, including IL-13, IL-4, eotaxins, thymus and activation-regulated chemokine, Il33, Ccl20, and SAM pointed domain-containing Ets transcription factor. Pulmonary inflammation and goblet cell differentiation were abrogated by treatment of neonatal Foxa2∆/∆ mice with mAb against IL-4Rα subunit. The respiratory epithelium plays a central role in the regulation of Th2-mediated inflammation and innate immunity in the developing lung in a process regulated by Foxa2.

To investigate whether corticosteroids are effective in the treatment of plastic bronchitis with hemoptysis.A retrospective, clinical study was undertaken. Thirty two patients with only first episodes of plastic bronchitis with hemoptysis were divided into a steroid group (n=18) treated with glucocorticoids, and a non-steroid group (n=14). The supportive therapy was uniformly applied to both groups, except for glucocorticoids. Variables such as temperature and white blood cell counts were determined. Furthermore, the volume of hemoptysis and bronchial casts were evaluated in detail daily.There was no difference in the demographic data and variables at baseline between both groups (all P0.05). On days 5, 6, 7 and 8, the volume of hemoptysis was significantly decreased in the steroid group compared with the non-steroid group (43+/-15 mL vs 117+/-33 mL on d 5, 29+/-12 mL vs 97+/-23 mL on d 6, 18+/-10 mL vs 80+/-20 mL on d 7, and 13+/-8 mL vs 66+/-14 mL on d 8; all P0.05), and on d 10 after fibreoptic bronchoscopy, the cases with bronchial casts was reduced evidently in the steroid group in comparison with the non-steroid group (OR=5.69, 95% CI=1.76-43.6; P=0.005). There was no significance in mechanical ventilation and mortality between both groups.Despite some limitations of this study, it has been demonstrated that, on the basis of common supportive therapy, corticosteroids would be effective and safe for the treatment of plastic bronchitis with hemoptysis.

Objective The present study investigated the effects of homocysteine on platelet activation induced by collagen and the downstream signaling pathways potentially involved in these effects. Methods Washed human platelets were incubated with homocysteine and collagen type I. The effects of homocysteine on platelet aggregation and adhesion and the tyrosine phosphorylation of total platelet proteins, Src kinase, and phospholipase-Cγ2 (PLCγ2) were studied. Results Homocysteine (10 to 100 μM) increased collagen-induced aggregation of washed platelets. Upon homocysteine (50 to 100 μM) treatment, platelet deposition to collagen-coated surface was significantly augmented under the low shear rate model (100/s) but not under the high shear rate model (1600/s). Collagen-stimulated total protein tyrosine phosphorylation in platelets was further enhanced by incubation with homocysteine. This effect was almost abrogated by genistein. Homocysteine potentiated collagen-stimulated tyrosine phosphorylation of the Src kinase and PLCγ2, which was partly decreased by integrin β1 blocking antibody. Conclusion Homocysteine (at 10 to 100 μM) potentiates collagen type I induced-platelet activation through signaling components of glycoprotein VI and integrin α2β1 pathway. Our results suggested that upregulation of tyrosine phosphorylation of proteins such as Src and PLCγ2 is involved in the downstream signaling events of homocysteine stimulation in human platelets.

This study aims to construct the plasmid of human Runx1 and observe its possible effects on Runx1 gene expression in human pulmonary adenocarcinoma cells (A549). The shRNA sequence targeting human Runx1 was designed and synthesized, then inserted into pSuper plasmid by DNA recombination technology. The recombinant plasmid was confirmed by bacterial colonies PCR, enzyme digestion analysis and DNA sequencing. A549 cells were transfected by Runx1 shRNA plasmid. The inhibition efficiency of pSuper-Runx1-shRNA plasmid on Runx1 at mRNA level and protein level were measured with real-time PCR and Western blot. The results of real-time PCR and Western blot indicated that the mRNA and protein levels of Runx1 in A549 cells were inhibited by the pSuper-Runx1- shRNA expression plasmid, and the inhibition rate were 33% and 50%, respectively.

Foxa2 [The forkhead box transcription factor-2; also known as HNF3B(hepatocyte nuclear factors-3), or TCF3B(transcription factor-3b) ] [Costa, 1989 #64], is a member of the Forkhead family of nuclear transcription factors that is highly expressed in respiratory epithelial cells lining conducting airways and in alveolar type Ⅱ cells in the development and mature lung. Foxa2 plays critical roles in lung development, which is required for normal lung maturation, surfactant protein and lipid synthesis, epithelial differentiation, and cross talking between epithelium and innate immune. Foxa2 can determine gene expression and cell fate in the lung, and is required for the suppression of Th2 immunity, mucus production, and goblet cell metaplasia in the developing lung in a process determined in part by its regulation of the Cysteinyl leukotriene (CysLT) pathway. Recent studies have implicated that Foxa2 is a suppressor of lung cancer. This review will summarize the role of Foxa2 in lung development, pulmonary diseases, and also the possible signaling pathways regulated by Foxa2.

Objective Unexplained weight loss is common in patients with chronic obstructive pulmonary disease (COPD). Because ghrelin plays an important role in energy homeostasis, this study investigated the plasma level of ghrelin in COPD. Methods Plasma ghrelin levels and levels of leptin, tumor necrosis factor-α, and C-reactive protein were measured in 29 patients with COPD and 17 healthy controls. Body composition was assessed with bioelectrical impedance analysis. Results Body mass index and percentage of body fat were lower in patients who had COPD than in healthy controls. Plasma ghrelin and leptin concentrations were significantly lower in patients who had COPD than in healthy controls (ghrelin: 0.25 ± 0.22 ng/mL versus 0.43 ± 0.24 ng/mL, P = 0.013; leptin: 1.77 ± 0.70 ng/mL versus 2.85 ± 0.96 ng/mL, P = 0.000). In contrast, tumor necrosis factor-α and C-reactive protein were significantly higher in those with COPD than in controls. Plasma ghrelin (log transformed) was positively correlated with body mass index and percentage of body fat in patients with COPD but negatively correlated in control subjects. Plasma ghrelin was negatively correlated with tumor necrosis factor-α and C-reactive protein in COPD. Conclusion Plasma ghrelin level was decreased in COPD and this is different from other weight-loss diseases. These data suggest that decreased ghrelin and other factors may contribute to alterations in metabolic status during inflammatory stress in this disease.

Background: Some peptides, which regulate the metabolic balance, are thought to play important roles in nutritional disorders and systemic inflammation in COPD. Treatment of rats with obestatin decreased body-weight gain. Obestatin was also found to be correlated with inflammation in rheumatoid arthritis. The aims of this study were to investigate the level of circulating obestatin in COPD and to analyze the relationship among obestatin and nutritional status, and systemic inflammation. Methods: 32 COPD patients with BMI less than 20 kg/m2 and 22 normal controls were included. Body composition was estimated using “foot-to-foot” BIA technology. Circulating obestatin was determined with enzyme-linked immunosorbent assay. Pulmonary function, TNF-α and C reactive protein were also measured. Results: The level of circulating obestatin was higher in COPD with underweight than that in normal control (5562.75 ± 3435.43 pg/ml in COPD, 3663.90 ± 2313.95 pg/ml in controls, p = 0.028). BMI, Waist circumference, hip circumference, bodyFAT and FAT% in COPD group were lower than those in normal control. Positive correlation was found among circulating C reactive protein, TNF-α and obestatin. There was no significant correlation among BMI, pulmonary function and obestatin. Conclusions: This study shows that circulating obestatin is higher in underweight COPD patients, and positively correlated to systemic inflammation, but not to nutritional status.

This study was aimed to construct transgenic mouse model with target for Runxl gene. Runxl cDNA of mice was amplified by PCR from pcDNA3. 1 Flag Runx1 FL vector and inserted into ptetO7-Asc-IRES-EGFP vector to form a recombinant vector, and then the recombinant vector was injected into fertilized egg by microinjection technology to get a transgenic mouse. The results of PCR and Southern blot indicated that the Runx1 transgenic mouse was constructed successfully, and this could provide an important tool for studying the function of Runxl gene in vivo.

Foxa2 is a member of the Forkhead family of nuclear transcription factors that is highly expressed in respiratory epithelial cells of the developing and mature lung. Foxa2 is required for normal airway epithelial differentiation, and its deletion causes goblet-cell metaplasia and Th2-mediated pulmonary inflammation during postnatal development. Foxa2 expression is inhibited during aeroallergen sensitization and after stimulation with Th2 cytokines, when its loss is associated with goblet-cell metaplasia. Mechanisms by which Foxa2 controls airway epithelial differentiation and Th2 immunity are incompletely known. During the first 2 weeks after birth, the loss of Foxa2 increases the production of leukotrienes (LTs) and Th2 cytokines in the lungs of Foxa2 gene–targeted mice. Foxa2 expression inhibited 15-lipoxygenase (Alox15) and increased Alox5 transcription, each encoding key lipoxygenases associated with asthma. The inhibition of the cysteinyl LT (CysLT) signaling pathway by montelukast inhibited IL-4, IL-5, eotaxin-2, and regulated upon activation normal T cell expressed and presumably secreted expression in the developing lungs of Foxa2 gene–targeted mice. Montelukast inhibited the expression of genes regulating mucus metaplasia, including Spdef, Muc5ac, Foxa3, and Arg2. Foxa2 plays a cell-autonomous role in the respiratory epithelium, and is required for the suppression of Th2 immunity and mucus metaplasia in the developing lung in a process determined in part by its regulation of the CysLT pathway.

For investigating the effect of Jumonji domain-containing protein-3 (JMJD3) on the behavior of lung cancer cell line, A549 proliferation was measured with EDU staining and flow cytometer after JMJD3 expression plasmid and pcDNA3. 1 transfection at 48h. The migration ability of A549 was tested at the same time. The expression of p21 mRNA was measured with RT-PCR. The results showed that JMJD3 transfection increased the EDU positive cells ratio (JMJD3: 40.75% +/- 2.07%, control: 20.97% +/- 1.5%, P0.001). G1 phase cell ration also increased after JMJD3 transfection (JMJD3:47. 80% +/- 1.85%, control: 54.60% +/- 0.95%, P = 0.005). The mRNA expression of p21 decreased in JMJD3 group (JMJD3: 35. 89% +/- 3.71%, control: 91.78% +/- 3.74%, P0.001). The distances of migration were (0.47 +/- 0.27) cm and (0.96 +/- 0.40) cm after 24h and 48h with JMJD3 tranfection, compared to (0.57 +/- 0.22)cm and (1.08 +/- 0.33)cm in control, respectively (P0.05). JMJD3 promoted the proliferation of A549 and decreased the G1 cell numbers, decreased the p21 mRNA, but had no effect on A549 migration.

To investigate the effect and mechanism of NK-1 Tachykinin receptor (NK-IR) antagonist on hypoxia induced hepatic injury, we established the hypoxic rat model. 30 male SD rats (weighing 240-300g) were randomly divided into 3 groups, control group, and experimental groups including the hypoxia group and the NK-1R antagonist group. The rats of experimental groups underwent hypoxia, among them the NK-1R antagonist group were those with interference of NK-1R antagonist by intraperitoneal injection. Hepatic injury was evaluated by pathological staining, hepatic function detection and hepatocellular apoptosis determination. Results showed hypoxia-induced hepatic injury in rats was established successfully. Edema,ballooning degeneration and spotty necrosis were found in livers in the experimental groups, among which the pathological injury in the hypoxia group was worse than that in the NK-1R antagonist group. Moreover,GGT and the rate of hepatocellular apoptosis in the NK-1R antagonist group were obviously lower than that in the hypoxia group (P0.05). But no significant difference were found in ALT,AST and ALP between groups (P0.05). These data indicate that Substance P possibly participate in the process of hypoxia-induced hepatic injury, and NK-1R antagonist could reduce hypoxia-induced hepatic injury.

The transition to air breathing after birth requires both anatomic and biochemical maturation of the lung. Lung morphogenesis is mediated by complex paracrine interactions between respiratory epithelial cells and mesenchymal cells that direct transcriptional programs guiding patterning and cytodifferentiation of the lung. In the present study, transgenic mice were generated in which the Kruppel-like factor 5 gene (Klf5) was conditionally deleted in respiratory epithelial cells in the fetal lung. Lack of KLF5 inhibited maturation of the lung during the saccular stage of development. Klf5Δ/Δ mice died of respiratory distress immediately after birth. Abnormalities in lung maturation and morphogenesis were observed in the respiratory epithelium, the bronchiolar smooth muscle, and the pulmonary vasculature. Respiratory epithelial cells of both the conducting and peripheral airways were immature. Surfactant phospholipids were decreased and lamellar bodies, the storage form of surfactant, were rarely found. mRNA microarray analysis demonstrated that KLF5 influenced the expression of genes regulating surfactant lipid and protein homeostasis, vasculogenesis, including Vegfa, and smooth muscle cell differentiation. KLF5 regulates genes controlling paracrine interactions during lung morphogenesis, as well as those regulating the maturation of the respiratory epithelium that is required for lung function after birth.

In a rat model, ghrelin has been shown to exert an anti-inflammatory effect in cardiovascular disease and arthritis. It also inhibits expression of proinflammatory cytokines. The wide tissue distribution of ghrelin expression and the presence of growth hormone secretagogue receptor (GHS-R) in the lung suggest that ghrelin may be a potential signal modulator in the lung. However, whether ghrelin exerts anti-inflammatory effects on acute lung injury induced by lipopolysaccharide (LPS) remains unknown. Therefore, we sought to investigate the role of ghrelin in LPS-induced acute lung injury and its underlying mechanism.We induced acute lung injury in rats via intratracheal instillation of LPS. We injected ghrelin and Nomega-nitro-L-arginine methyl ester (L-NAME) through the tail vein. Lung injury was assessed by histologic examination 6 hours after injury. Lung macrophages were isolated and incubated with LPS, L-NAME, and ghrelin. Concentrations of TNF-alpha and IL-1beta in bronchoalveolar lavage (BAL) fluid and culture supernatant were determined by enzyme-linked immunosorbent assay (ELISA). Nitric oxide (NO) in BAL fluid and culture supernatant and NO synthase (NOS) in cultured macrophage were detected by a spectrophotometry.Ghrelin attenuated pulmonary inflammation in LPS-induced acute lung injury, decreased production of proinflammatory cytokines, and increased NO concentrations in BAL fluid. Ghrelin also suppressed LPS-induced expression of proinflammatory cytokines, and increased NOS activity in cultured macrophages and NO concentrations in culture supernatants. The anti-inflammatory effect of ghrelin was inhibited by L-NAME.Ghrelin attenuates LPS-induced acute lung inflammation and suppresses LPS-induced proinflammatory cytokine production in lung macrophages, which is partially mediated by increased NO production.

Hypoxia-inducible transcription factor-1alpha (HIF-1alpha) is a "master" gene in the cell hypoxia response network. HIF-1alpha plays the key role on VEGF-dependent angiogenesis during tumor development. In this study, the siRNA expressive vector targeting HIF-1alpha was constructed. HepG2 cells were tranfected with an HIF-1alpha siRNA vector and exposed to a normoxic or hypoxic environment. mRNA and protein levels of HIF-1alpha and VEGF were detected by RT-PCR and Western blot at different cell culture environment. The mRNA and protein expression of HIF-1alpha was inhibited by RNA interference. The obvious decreases of mRNA and protein of VEGF was induced by HIF-1alpha gene knock-down. Our study indicated that HIF-1alpha regulated the expression of VEGF and hence promoted angiogenesis in liver cancer under hypoxic environment. The expression of VEGF was downregulated via HIF-1alpha gene knock-down. These results suggest that HIF-1alpha may be used as a good target gene for anti-angiogenesis in liver tumors.

Malnutrition and continuous systemic inflammation occur frequently in patients with chronic obstructive pulmonary disease (COPD). Visfatin is a new adipokine, which increases in some inflammatory diseases. Its plasma level and relation with nutritional status and inflammation in COPD remain unknown. This study compared visfatin levels, nutritional status, and inflammation markers in patients with COPD and healthy controls.Plasma visfatin, tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein (CRP) were measured in 35 patients with COPD and 28 healthy controls. Body composition was assessed with bioelectrical impedance analysis.Significantly lower body mass index and percentage of body fat were observed in patients with COPD compared with control subjects. The levels of plasma visfatin were higher in the COPD group compared with healthy controls (2.07 +/- 0.18 versus 1.88 +/- 0.15 ng/mL, P0.001). Levels of TNF-alpha and CRP were also significantly higher in patients with COPD compared with controls. Plasma CRP and TNF-alpha were positively correlated with visfatin in the COPD group. No significant correlations were found between visfatin and body mass index or percentage of body fat in both groups.Plasma visfatin levels increased in patients with COPD. This increased adipocytokine was significantly correlated with TNF-alpha and CRP. Visfatin may be a new proinflammatory adipocytokine in this disease.

Summary. Background: Increased homocysteine levels in blood might be an important risk factor for the development of cardiovascular diseases. Connective tissue growth factor (CTGF) was found to be involved in atherosclerotic plaque progression. So far, the possible connection between homocysteine and CTGF has not been studied. Objective: This study was designed to test whether homocysteine could induce CTGF expression in vascular smooth muscle cells (VSMC). Methods and results: Hyperhomocysteinemia was induced in Sprague–Dawley rats after 4 weeks of a high-methionine diet. CTGF mRNA and protein expression was detected in the aortas isolated from hyperhomocysteinemic rats, but not in the controls. The underlying mechanism of homocysteine-induced CTGF expression was investigated in cultured human umbilical vein smooth muscle cells (HUVSMC). CTGF mRNA expression was induced after treatment with dl-homocysteine (50 μmol L−1) for 1 h, which remained at the elevated level for up to 8 h. CTGF protein level increased after homocysteine treatment for 8 h, and the elevated status was maintained for up to 48 h. Several intracellular signals elicited by homocysteine are involved in CTGF synthesis, including protein kinase C (PKC) activation and reactive oxygen species (ROS). Transfection HUVSMCs with a CTGF small interference RNA (siRNA) plasmid, which specifically inhibited the expression of CTGF, decreased extracellular matrix (ECM) accumulation caused by homocysteine. Conclusion: Our results demonstrate that homocysteine could increase the expression of CTGF in VSMC both in vivo and in vitro. The novel findings suggest that homocysteine might contribute to accelerated progression of atherosclerotic lesions by inducing CTGF expression.

To explore the effect of Astragalus membranaceus (AM) on T-helper cell type 1 (Thl) specific transcription factor T-box expressed in T cells (T-bet) expression and Thl/Th2 equilibrium.The levels of T-bet mRNA in peripheral blood mononuclear cells (PBMCs) from 15 patients with asthma and 15 healthy subjects were determined by reverse transcription-polymerase chain reaction (RT-PCR). PBMCs in asthma patients were incubated with AM and then the concentration of interferon gamma (IFN-gamma) and interleukin-4 (IL-4) in the supernate before and after AM intervention were determined by ELISA. The numbers of CD4 + CCR3 + and CD4 + CCR5 + cells were counted by flow cytometry.The expression of T-bet mRNA and the level of IFN-gamma were lower, but level of serum IL-4 was higher in asthma patients when compared with those in healthy subjects respectively. After AM (60 microg/ml) intervention, the former two parameters raised and showed a positive correlation between them, while the level of IL-4 was decreased. The mean percentage of CD4 + CCR3 + cells in asthma patients was significantly higher but that of CD4 + CCR5 + cells was lower when compared with those in healthy subjects respectively. After AM intervention, the abnormal change in the two indexes was improved to certain extent, showing a reversing status of Th2 polarization.AM could increase the expression of T-bet mRNA and Thl cytokines such as IFN-Y, and might reverse the Th2 predominant status in asthma patients.

Background Connective tissue growth factor (CTGF) is a potent profibrotic factor, which is implicated in fibroblast proliferation, angiogenesis and extracellular matrix (ECM) synthesis. It is a downstream mediator of some of the effects of transforming growth factor β (TGFβ) and is potentially induced by hyperglycemia in human renal mesangial cells. However, whether high glucose could induce the CTGF expression in vascular smooth muscle cells (VSMCs) remains unknown. Therefore, this study was designed to test whether high glucose could regulate CTGF expression in human VSMC. The effect of modulating CTGF expression on VSMC proliferation and migration was further investigated. Results Expression of CTGF mRNA was up-regulated as early as 6 hours in cultured human VSMCs after exposed to high glucose condition, followed by ECM components (collagen type I and fibronectin) accumulation. The upregulation of CTGF mRNA appears to be TGFβ-dependent since anti-TGFβ antibody blocks the effect of high glucose on CTGF gene expression. A small interference RNA (siRNA) targeting CTGF mRNA (CTGF-siRNA) effectively suppressed CTGF up-regulation stimulated by high glucose up to 79% inhibition. As a consequence of decreased expression of CTGF gene, the deposition of ECM proteins in the VSMC was also declined. Moreover, CTGF-siRNA expressing vector partially inhibited the high glucose-induced VSMC proliferation and migration. Conclusion Our data suggest that in the development of macrovascular complications in diabetes, CTGF might be an important factor involved in the patho-physiological responses to high glucose in human VSMCs. In addition, the modulatory effects of CTGF-siRNA during this process suggest that specific targeting CTGF by RNA interference could be useful in preventing intimal hyperplasia in diabetic macrovascular complications.

The transcription factor forkhead box protein A2 (FOXA2, also known as hepatocyte nuclear factor 3β or transcription factor 3β), has been found to play pivotal roles in multiple phases of mammalian life, from the early development to the organofaction, and subsequently in homeostasis and metabolism in the adult. In the embryonic development period, FOXA2 is require d for the formation of the primitive node and notochord, and its absence results in embryonic lethality. Moreover, FOXA2 plays an important role not only in lung development, but also in T helper type 2 (Th2)-mediated pulmonary inflammation and goblet cell hyperplasia. In this article, the role of FOXA2 in lung development and Th2-mediated pulmonary inflammation, as well as in goblet cell hyperplasia, is reviewed. FOXA2 deletion in airway epithelium results into Th2-mediated pulmonary inflammation and goblet cell hyperplasia in developing lung. Leukotriene pathway and signal transducers and activators of transcription 6 pathway may mediate this inflammation through recruitment and activation of denditric cell during lung developments. FOXA2 is a potential treatment target for lung diseases with Th2 inflammation and goblet cell hyperplasia, such as asthma and chronic obstructive pulmonary disease.

Background Patients with asthma demonstrate circadian variations in the airway inflammation and lung function. Pinealectomy reduces the total inflammatory cell number in the asthmatic rat lung. We hypothesize that melatonin, a circadian rhythm regulator, may modulate the circadian inflammatory variations in asthma by stimulating the chemotaxins expression in the lung epithelial cell. Methods Lung epithelial cells (A549) were stimulated with melatonin in the presence or absence of TNF-α(100 ng/ml). RANTES (Regulated on Activation Normal T-cells Expressed and Secreted) and eotaxin expression were measured using ELISA and real-time RT-PCR, eosinophil chemotactic activity (ECA) released by A549 was measured by eosinophil chemotaxis assay. Results TNF-α increased the expression of RANTES (307.84 ± 33.56 versus 207.64 ± 31.27 pg/ml of control, p = 0.025) and eotaxin (108.97 ± 10.87 versus 54.00 ± 5.29 pg/ml of control, p = 0.041). Melatonin(10-10 to 10-6M) alone didn't change the expression of RNATES (204.97 ± 32.56 pg/ml) and eotaxin (55.28 ± 6.71 pg/ml). However, In the presence of TNF-α (100 ng/ml), melatonin promoted RANTES (410.88 ± 52.03, 483.60 ± 55.37, 559.92 ± 75.70, 688.42 ± 95.32, 766.39 ± 101.53 pg/ml, treated with 10-10, 10-9, 10-8, 10-7,10-6M melatonin, respectively) and eotaxin (151.95 ± 13.88, 238.79 ± 16.81, 361.62 ± 36.91, 393.66 ± 44.89, 494.34 ± 100.95 pg/ml, treated with 10-10, 10-9, 10-8, 10-7, 10-6M melatonin, respectively) expression in a dose dependent manner in A549 cells (compared with TNF-α alone, P < 0.05). The increased release of RANTES and eotaxin in A549 cells by above treatment were further confirmed by both real-time RT-PCR and the ECA assay. Conclusion Taken together, our results suggested that melatonin might synergize with pro-inflammatory cytokines to modulate the asthma airway inflammation through promoting the expression of chemotaxins in lung epithelial cell.

To investigate the expression of smooth muscle actin(SMA)-alpha mRNA in the lung of rat with asthma.A rat model of asthma was established by exposing the animal to aerosolized ovalbumin (OA). After being sensitized, the rat was subjected to laboratory tests. alpha-SMA mRNA of the lung tissue was measured by RT-PCR. The thickness of the airway smooth muscle(ASM) was measured by an image analysis system at the same time.The thickness of ASM increased 2 weeks after OA challenge. The expression of alpha-SMA mRNA increased 1 week after OA challenge and increased more significantly after 2 weeks.In the rat model of asthma, hypertrophy and hyperplasia of the airway smooth muscle were noted, and the phenotype was changed.

To investigate the effect of inhaled glucocorticoids on the expression of Clara cell secretory protein (CCSP) and its mRNA in lung tissue of a rat model of asthma.The rat asthmatic model was established by sensitizing and challenging SD rats with aerosolized ovalbumin (OVA). Rats were divided into a control, an asthmatic and a glucocorticoid groups. Budesonide aerosol was delivered by a jet nebulizer. The CCSP mRNA level in the lung tissue and the CCSP level in bronchoalveolar lavage fluid (BALF) were determined by RT-PCR and dot immuno-blotting, respectively.The level of CCSP mRNA in the lung tissue was 0.65 +/- 0.04 in the control, 0.56 +/- 0.05 in the asthmatic and 0.63 +/- 0.04 in the glucocorticoid groups, respectively (asthma versus control, P0.01; glucocorticoid versus asthma, P0.05). The CCSP level in BALF was 60 +/- 5 in the control, 49 +/- 5 in the asthmatic and 57 +/- 5 in the glucocorticoid groups, respectively (asthma versus control, P0.01; glucocorticoid versus asthma, P0.05). Budesonide reduced the percentage of eosinophils in BALF and inhibited airway inflammation.OVA challenge in the rat model decreased CCSP mRNA, resulting in a reduction in CCSP production, which may contribute to asthmatic airway inflammation. Inhaled glucocorticoids increased the expression of CCSP mRNA in lung tissue, which may be a mechanism for the suppression of airway inflammation by glucocorticoids.

BackgroundHypoxia-inducible transcription factor-1α (HIF-1α), which plays an important role in controlling the hypoxia-induced glycolysis pathway, is a "master" gene in the tissue hypoxia response during tumor development. However, its role in the apoptosis of non-small cell lung cancer remains unknown. Here, we have studied the effects of HIF-1α on apoptosis by modulating HIF-1α gene expression in A549 cells through both siRNA knock-down and over-expression.MethodsA549 cells were transfected with a HIF-1α siRNA plasmid or a HIF-1α expression vector. Transfected cells were exposed to a normoxic or hypoxic environment in the presence or absence of 25 mM HEPES and 2-deoxyglucose (2-DG) (5 mM). The expression of three key genes of the glycolysis pathway, glucose transporter type 1(GLUT1), phosphoglycerate kinase 1(PGK1), and hexokinase 1(HK1), were measured using real-time RT-PCR. Glycolysis was monitored by measuring changes of pH and lactate concentration in the culture medium. Apoptosis was detected by TUNEL assay and flow cytometry.ResultsKnocking down expression of HIF-1α inhibited the glycolysis pathway, increased the pH of the culture medium, and protected the cells from hypoxia-induced apoptosis. In contrast, over-expression of HIF-1α accelerated glycolysis in A549 cells, decreased the pH of the culture medium, and enhanced hypoxia-induced apoptosis. These effects of HIF-1α on glycolysis, pH of the medium, and apoptosis were reversed by treatment with the glycolytic inhibitor, 2-DG. Apoptosis induced by HIF-1α over-expression was partially inhibited by increasing the buffering capacity of the culture medium by adding HEPES.ConclusionDuring hypoxia in A549 cells, HIF-1α promotes activity of the glycolysis pathway and decreases the pH of the culture medium, resulting in increased cellular apoptosis.

Background Pulsed electromagnetic field (PEMF) is a non-invasive physical therapy used in the treatment of fracture nonunion or delayed healing. PEMF can facilitate the osteogenic differentiation of bone marrow mesenchymal stem cells in vitro. Amniotic epithelial cells (AECs) have been proposed as a potential source of stem cells for cell therapy. However, whether PEMF could modulate the osteogenic differentiation of AECs is unknown. In the present study, the effects of PEMF on the osteogenic differentiation of AECs were investigated. Methods AECs were isolated from amniotic membrane of human placenta by trypsin digestion and were induced by PEMF and/or osteo-induction medium. After 21 days we used real time RT-PCR and immunocytochemistry to study the expression of osteoblast markers. The signal transduction of osteogenesis was further investigated. Results The PEMF stimulation, or osteo-induction medium alone could induce osteogenic differentiation of AECs, as shown by expression of osteoblast specific genes and proteins including alkaline phosphatase and osteocalcin. Furthermore, a combination of PEMF and osteo-induction medium had synergy effects on osteogenic differentiation. In our study, the gene expression of BMP-2, Runx2, β-catenin, Nrf2, Keap1 and integrinβ1 were up-regulated in the osteogenic differentiation of AECs induced by PEMF and/or osteo-induction medium. Conclusions Combined application of PEMF and osteo-induction medium is synergistic for the osteogenic differentiation of AECs. It might be a novel approach in the bone regenerative medicine.

Background Hypoxia plays an important role in vascular remodeling and directly affects vascular smooth muscle cells (VSMC) functions. Macrophage migration inhibitory factor (MIF) is a well known proinflammatory factor, and recent evidence suggests an important role of MIF in the progression of atherosclerosis and restenosis. However, the potential link between hypoxia and MIF in VSMC has not been investigated. The current study was designed to test whether hypoxia could regulate MIF expression in human VSMC. The effect of modulating MIF expression on hypoxia-induced VSMC proliferation and migration was also investigated at the same time. Results Expression of MIF mRNA and protein was up-regulated as early as 2 hours in cultured human VSMCs after exposed to moderate hypoxia condition (3% O2). The up-regulation of MIF expression appears to be dependent on hypoxia-inducible transcription factor-1α(HIF-1α) since knockdown of HIF-1α inhibits the hypoxia induction of MIF gene and protein expression. The hypoxia induced expression of MIF was attenuated by antioxidant treatment as well as by inhibition of extracellular signal-regulated kinase (ERK). Under moderate hypoxia conditions (3% O2), both cell proliferation and cell migration were increased in VSMC cells. Blocking the MIF by specific small interference RNA to MIF (MIF-shRNA) resulted in the suppression of proliferation and migration of VSMCs. Conclusion Our results demonstrated that in VSMCs, hypoxia increased MIF gene expression and protein production. The hypoxia-induced HIF-1α activation, reactive oxygen species (ROS) generation and ERK activation might be involved in this response. Both MIF and HIF-1α mediated the hypoxia response of vascular smooth muscle cells, including cell migration and proliferation.

Background Atherosclerosis is now recognized as a chronic inflammatory disease. Angiotensin II (Ang II) is a critical factor in inflammatory responses, which promotes the pathogenesis of atherosclerosis. Placental growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family cytokines and is associated with inflammatory progress of atherosclerosis. However, the potential link between PlGF and Ang II has not been investigated. In the current study, whether Ang II could regulate PlGF expression, and the effect of PlGF on cell proliferation, was investigated in human vascular endothelial cells (VECs) and smooth muscle cells (VSMCs). Results In growth-arrested human VECs and VSMCs, Ang II induced PlGF mRNA expression after 4 hour treatment, and peaked at 24 hours. 10-6 mol/L Ang II increased PlGF protein production after 8 hour treatment, and peaked at 24 hours. Stimulation with Ang II also induced mRNA expression of VEGF receptor-1 and -2(VEGFR-1 and -2) in these cells. The Ang II type I receptor (AT1R) antagonist blocked Ang II-induced PlGF gene expression and protein production. Several intracellular signals elicited by Ang II were involved in PlGF synthesis, including activation of protein kinase C, extracellular signal-regulated kinase 1/2 (ERK1/2) and PI3-kinase. A neutralizing antibody against PlGF partially inhibited the Ang II-induced proliferation of VECs and VSMCs. However, this antibody showed little effect on the basal proliferation in these cells, whereas blocking antibody of VEGF could suppress both basal and Ang II-induced proliferation in VECs and VSMCs. Conclusion Our results showed for the first time that Ang II could induce the gene expression and protein production of PlGF in VECs and VSMCs, which might play an important role in the pathogenesis of vascular inflammation and atherosclerosis.