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Objectives Chemoresistance induced by cisplatin has become the major impediment to lung cancer chemotherapy. This study explored the potential chemoresistant genes and underlying mechanisms of chemoresistance in NSCLC. Materials and methods Gene expression profile was integrated with DNA methylation profile to screen the candidate chemoresistant genes. Bioinformatic analysis and immunohistochemistry were used to analyse the association of a candidate gene with the characteristics of NSCLC patients. Recombinant lentivirus vectors were utilized to overexpress or silence candidate gene. Microarrays and immunoblotting were applied to explore the downstream targets of candidate gene. Xenograft models were established to validate the findings in vitro. Results An increased ZNF300 expression was detected in three chemoresistant cell lines of NSCLC, and the higher expression of ZNF300 was associated with poor OS of NSCLC patients. Cells with upregulated ZNF300 presented chemoresistance and enhanced aggressive growth compared to cells with downregulated ZNF300. ZNF300 inhibited MAPK/ERK pathways and activated CDK1 through inhibiting WEE1 and MYT1 and modulating MYC/AURKA/BORA/PLK1 axis. ICA and ATRA improved the anti‐tumour effect of cisplatin on chemoresistant cells by inducing differentiation. Conclusions ZNF300 promotes chemoresistance and aggressive behaviour of NSCLC through regulation of proliferation and differentiation by downregulating MAPK/ERK pathways and regulation of slow‐cycling phenotype via activating CDK1 by inhibiting WEE1/MYT1 and modulating MYC/AURKA/BORA/PLK1 axis. Cisplatin, combined with ATRA and ICA, might be beneficial in chemoresistant cases of NSCLC., ZNF300 mediates chemoresistance of NSCLC. ZNF300 promotes aggressive growth of tumour cells correlating to poor prognosis of patients with NSCLC. ZNF300 inhibits MAPK/ERK signalling pathway to suppress proliferation and differentiation of chemoresistant cells. ZNF300 activates CDK1 by inhibiting WEE1 and MYT1 and modulating MYC/AURKA/BORA/PLK1 axis to regulate cell cycle of chemoresistant cells. ICA and ATRA improves anti‐tumour effect of cisplatin on chemoresistant cells by inducing differentiation.

Background: Chemo-resistance induced by cisplatin (DDP) has become the major impediment to lung cancer chemotherapy. The study aimed to unearth an alternative route for reversing chemo-resistance and suppressing the malignant progression of tumors. Methods: Gene expression profile was integrated with DNA methylation profile of A549/DDP cells of human adenocarcinoma. Immunohistochemistry were used to analyze the association of gene with characteristics of NSCLC patients. Cell viability, apoptosis, cell cycle, migration, engulfment, and senescence were assessed between the different groups of cells. Genes related with differentiation and cell cycle, screened by microarrays, were examined by immunoblotting. Xenograft model was utilized to validate the results in vitro. Findings: ZNF300 was association with poor overall survival of NSCLC patients. Multidrug-resistant cells exhibited a more malignant behavior related to chemo-sensitive cells. Most of genes related with differentiation, cyclin-dependent kinase inhibitor, and MAPK/ERK pathways were downregulated, while most of genes related with cell cycle and cancer stem cell were upregulated in multidrug-resistant cells compared to chemo-sensitive cells. ICA improved the antitumor effect of cisplatin on multidrug-resistant cells. Interpretation: ZNF300 promoted the malignant behavior of multidrug-resistant cells through inhibiting differentiation via supressing MAPK/ERK pathways and enhancing cancer stem cell-like properties via upregulating Nanog and OCT4. Additionally, CDK1 activated by ZNF300 via inhibiting WEE1 and MYT1 and modulating AURKA/BORA/PLK1/CDC25 cascade promoted cells to enter cell cycle and escape the apoptosis caused by chemotherapeutic drug. ICA improved the antitumor effect of cisplatin on multidrug resistant cells by inducing differentiation. Funding Statement: This work was supported by the National Natural Scientific Fund of China (№:81372499), the Cultivating Project for Young Scholar at Hubei University of Medicine ( № :2018QDJZR01 and 2018QDJZR11), and the Open Project of Hubei Key Laboratory of Wudang Local Chinese Medicine Research (Hubei University of Medicine) (№:WDCM2018002). Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: The informed consents were obtained from all the patients undertaking surgery and participating in this study. All animal experiments were authorized by the Experimental Animal Ethics Committee of Xinqiao Hospital of the Army Medical University [SYXK(YU)2012-0011] and Hubei University of Medicine [SYXK(E)2016-0031].

Fibromodulin (FMOD), an ECM small leucine-rich proteoglycan (SLRP), was reported to promote angiogenesis not only during wound healing, but also in optical and cutaneous angiogenesis-dependent diseases. However, whether it plays important roles in tumor angiogenesis remains unclear. To explore the role of FMOD in tumor angiogenesis of human small cell lung cancer (SCLC), initially the study analyzed the relationship of FMOD expression in cancer tissues of SCLC with clinical characteristics. The analysis revealed that the positive FMOD expression was significantly associated with extensive stage of SCLC and higher vascular density. In mouse models, xenograft tumors developed with FMOD-silenced H446 cells (H446-shFMOD) exhibited slowed growth rate, decreased microvessel density, and reduced blood perfusion related to that of controls (H446-shCON). Additionally, compared with that of controls, the decreased secretion of FMOD in conditioned medium (CM) from H446-shFMOD inhibited proliferation, migration, and invasion of human umbilical vessel endothelial cells (HUVECs). Moreover, the decreased secretion of FMOD downregulated the expression of VEGF, TGF-β1, FGF-2, and PDGF-B in HUVECs. The findings strongly suggested that the autocrine FMOD of cancer cells may promote tumor angiogenesis of SCLC by upregulating the expression of angiogenic factors that act in concert to facilitate the angiogenic phenotype of endothelial cells as a proangiogenic factor. Therefore, silencing FMOD may be a potentially clinical therapy for repressing tumor angiogenesis.

Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling.

Lung inflammation and alveolar epithelial cell death are critical events in the development and progression of acute lung injury (ALI). Although angiopoietin-like protein 4 (ANGPTL4) participates in inflammation, whether it plays important roles in ALI and alveolar epithelial cell inflammatory injury remains unclear. We therefore investigated the role of angptl4 in lipopolysaccharide (LPS)-induced ALI and the associated mechanisms. Lentivirus-mediated short interfering RNA targeted to the mouse angptl4 gene (AngsiRNA) and a negative control lentivirus (NCsiRNA) were intranasally administered to mice. Lung inflammatory injury and the underlying mechanisms for regulation of angptl4 on the LPS-induced ALI were subsequently determined. We reported that angptl4 levels were increased both in human alveolar epithelial A549 cells and lung tissues obtained from a mouse model of LPS-induced ALI. Angptl4 expression was induced by LPS in alveolar epithelial cells, whereas LPS-induced lung inflammation (neutrophils infiltration in the lung tissues, tumor necrosis factor α, interleukin 6), lung permeability (lung wet/dry weight ratio and bronchoalveolar lavage fluid (BALF) protein concentration), tissue damage (caspase3 activation), and mortality rates were attenuated in AngsiRNA-treated mice. The inflammatory reaction (tumor necrosis factor α, interleukin 6) and apoptosis rates were reduced in AngsiRNA(h)-treated A549 cells. Moreover, angptl4 promoted NF-kBp65 expression and suppressed SIRT1 expression both in mouse lungs and A549 cells. Additionally, SIRT1 antagonist nicotinamide (NAM) attenuated the inhibitory effects of AngsiRNA both on LPS-induced NF-kBp65 expression and IL6 expression. These findings suggest that silencing angptl4 protects against LPS-induced ALI via regulating SIRT1/NF-kB signaling pathway. J. Cell. Physiol. 230: 2390–2402, 2015. © 2015 Wiley Periodicals, Inc.

Our previous work has demonstrated that the cellular phenotype changes of human pulmonary artery smooth muscle cells (PASMCs) play an important role during pulmonary vascular remodelling. However, little is known about the role of PASMCs phenotype modulation in the course of hypoxia-induced migration and its behind molecular mechanisms. In this study, we have shown that cGMP-dependent protein kinase (PKG) Iα transfection significantly attenuated the hypoxia-induced down-regulation of the expressions of SM-α-actin, MHC and calponin. Hypoxia-induced PASMC migration was also suppressed by PKGIα overexpression. Furthermore, this overexpression attenuated ANX A1 upregulation under hypoxic conditions. All those effects were reversed by a PKG inhibitor KT5823. Our data indicate that manipulating upstream entity e.g., PKGIa, may have a potential therapeutic value to prevent hypoxia–associated pulmonary arterial remodeling for pulmonary hypertension development.

The objectives of this study were to detect the immunogenicity of a lipopolysaccharide (LPS) binding protein (LBP) mimic epitope peptide vaccine and evaluate its effect on controlling excessive and uncontrolled inflammatory reactions in mice with acute lung injury. The vaccine was prepared by mixing self-made LBP mimic epitope multiple antigen peptide (MAP) and Freund adjuvants in a proper proportion. Healthy mice were inoculated with the vaccine and the dynamic changes of anti-MAP antibody were measured using ELISA. Anti-MAP antibody was prepared from the immune serum of the mice based on the standard antibody preparation program. Western blot assay was used to identify LBP specificity of anti-MAP antibody. Anti-MAP antibody bioactivity was analyzed using in vitro binding activity test. Following the vaccine inoculation, the mice were injected with LPS to induce acute lung injury. Anti-MAP antibody prepared was also used to immune the mice with LPS-induced acute lung injury. TNF-α and IL-1β contents in serum and lung tissue homogenate were measured using double antibody sandwiched ELISA at different time-points after LPS challenge. At 8h time-point, total white blood cell counts, polymorphonuclear leucocyte count and protein content in bronchoalveolar lavage fluid were measured and pulmonary morphological changes were evaluated. The antibody titer was gradually rising, reaching to its peak at 8th week and lasting to the tenth week. The antibody possessed strong immunogenicity, high specificity and favorable biologic activity. Whole range inoculation of LBP mimic epitope peptide vaccine or anti-MAP antibody intervention partly eliminates LPS-mediated acute lung injury. In conclusion, LBP mimic epitope peptide vaccine successfully induced highly specific antibody with high bioactivity in mice. LBP mimic epitope peptide vaccine and anti-MAP antibody inhibited excessive and uncontrolled inflammatory reactions from LPS-mediated acute lung injury in mice.

Hypoxia down-regulates the expression of the growth arrest-specific homeobox (Gax) in pulmonary arterial smooth muscle cells (PASMCs), resulting in increased cell proliferation and decreased apoptosis, but the mechanism for this response remains unclear. The present study investigated the role of Gax in the development of hypoxia-induced pulmonary hypertension (PH). We found that hypoxia suppressed the expression of endogenous Gax in rats, but not in those pretreated intratracheally with a Gax construct (Ad-Gax). Hypoxic rats pretreated with Ad-Gax were resistant to hypoxia-induced PH, right ventricular hypertrophy, increased wall thickness, and the muscularization of pulmonary arterioles. Hypoxia-induced PASMC proliferation and suppression of Gax expression were blocked by the Mitogen-activated protein kinase (MEK) inhibitor U0126. The PASMCs with Ad-Gax transfection exhibited hyperexpression of the Bcl-2-associated X protein (Bax) and hypoexpression of B-cell lymphoma 2 (Bcl-2), leading to cell apoptosis. Thus, our data indicate that the enhanced expression of Gax inhibits hypoxia-induced PASMC proliferation, probably via the extracellular-signal-regulated kinase (ERK) 1/2 pathway, and induces the apoptosis of hypoxic PASMCs via the Bcl-2/Bax pathway. Gax may be a potential new therapeutic target for pulmonary hypertension.

Recent findings identify the role of proliferation of pulmonary artery smooth muscle cells (PASMCs) in pulmonary vascular remodeling. Phosphoinositide 3 kinase (PI3K) and serine/threonine kinase (Akt) proteins are expressed in vascular smooth muscle cells. In addition, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) has been identified as a negative regulator of cytokine signaling that inhibits the PI3K-Akt pathway. However, little is known about the role of PTEN/Akt signaling in hypoxia-associated vascular remodeling. In this study, we found that hypoxia-induced the expression of Akt1 mRNA and phosphorylated protein by at least twofold in rat PASMCs. Phospho-PTEN significantly decreased in the nuclei of PASMCs after hypoxic stimulation. After forcing over-expression of PTEN by adenovirus-mediated PTEN (Ad-PTEN) transfection, the expression of phospho-Akt1 was significantly suppressed in PASMCs at all time-points measured. Additionally, we showed here that hypoxia increased proliferation of PASMCs by nearly twofold and over-expression of PTEN significantly inhibited hypoxia-induced PASMCs proliferation. These findings suggest that phospho-PTEN loss in the nuclei of PASMCs under hypoxic conditions may be the major cause of aberrant activation of Akt1 and may, therefore, play an important role in hypoxia-associated pulmonary arterial remodeling. Finally, the fact that transfection with Ad-PTEN inhibits the phosphorylation of Akt1 in PASMCs suggests a potential therapeutic effect on hypoxia-associated pulmonary arterial remodeling.

Human airway epithelial cells (HAEC) may contribute to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) through toll-like receptors (TLRs)-mediated molecular mechanisms. TLRs exist on the surface of HAEC where binding to their cognate ligands initiates airway inflammation. Single immunoglobulin interleukin-1 receptor-related protein (SIGIRR) is a member of the toll-interleukin-1 receptor (TIR) family that can negatively modulate the immune response. We carried out studies to characterize SIGIRR modulation of TLR-mediated immune response in HAEC and to define its mechanisms of action. Following treatment with various concentrations of LPS, flagellin and CpG DNA, the levels of cognate TLRs 4, 5, and 9 were measured in the supernatants of HAEC over-expressing the SIGIRR molecule. Moreover, the interaction of the TLR adaptor myeloid differentiation factor 88 (MyD88) with SIGIRR in response to LPS-, flagellin- and CpG DNA-stimulation was examined by co-immunoprecipitation. The findings from this study revealed that overexpression of SIGIRR in HAEC stimulated by LPS, flagellin or CpG DNA resulted in attenuated production of the inflammatory mediators IL-6 and TNF-α. This attenuation was not the result of decreased expression of TLR4, 5 or 9, but rather a sequestration of MyD88 to the TLRs. In conclusion, SIGIRR can inhibit TLR4, 5, and 9-mediated immune responses in HAEC and may be a valuable therapeutic target for the prevention of ALI/ARDS.

The aim of this study was to investigate whether P12, a lipopolysaccharide (LPS)-binding protein (LBP) inhibitory peptide could reduce LPS induced inflammation in vitro and in vivo.Human monocyte-like cell line (U937 cells) was grown in RPMI 1640 and stimulated with PMA in order to induce differentiation to the macrophage stage. A total of 70 Kunming mice (8-12 wk old) were used in our experiments. The effects of P12 on the binding of LPS to U937 cells and alveolar macrophages (AMs) were determined by flow cytometric analysis. Nuclear factor kappa B (NF-kappa B) translocation was evaluated with subunit P65 by Western blotting. The production of tumor necrosis factor-alpha (TNF-alpha), alanine transaminase (ALT), and nitric oxide (NO) as measured by ELISA, enzymatic activity assay, and enzymatic assay with nitrate reductase. Differences among groups were determined using one-way ANOVA test and Fisher exact test.U937 cells were treated with LPS, LBP, and indicated concentrations of P12. Mice were administered LPS intraperitoneally and P12 via the tail vein.P12 inhibited the binding of FITC-conjugated LPS (FITC-LPS) to U937 cells and AMs. NF-kappa B translocation and the production of TNF-alpha, ALT, and NO induced by LPS was also significantly suppressed by P12. Furthermore P12 protected mice from LPS-induced death.The results suggest that blockade of LBP at inflammation sites might attenuate LPS-induced circulatory shock. This results in a beneficial effect in a mouse model of endotoxemia.

The syndrome of high-altitude de-acclimatization commonly takes place after long-term exposure to high altitudes upon return to low altitudes. The syndrome severely affects the returnee's quality of life. However, little attention has been paid to careful characterization of the syndrome and their underlying mechanisms. Male subjects from Chongqing (n = 67, 180 m) and Kunming (n = 70, 1800 m) visited a high-altitude area (3650 m) about 6 months and then returned to low-altitude. After they came back, all subjects were evaluated for high-altitude de-acclimatization syndrome on the 3(rd), 50(th), and 100(th). Symptom scores, routine blood and blood gas tests, and myocardial zymograms assay were used for observation their syndrome. The results showed that the incidence and severity of symptoms had decreased markedly on the 50(th) and 100(th) days, compared with the 3(rd) day. The symptom scores and incidence of different symptoms were lower among subjects returning to Kunming than among those returning to Chongqing. On the 3(rd) day, RBC, Hb, Hct, CK, CK-MB, and LDH values were significantly lower than values recorded at high altitudes, but they were higher than baseline values. On the 50(th) day, these values were not different from baseline values, but LDH levels did not return to baseline until the 100(th) day. These data show that, subjects who suffered high-altitude de-acclimatization syndrome, the recovery fully processes takes a long time (≥ 100(th) days). The appearance of the syndrome is found to be related to the changes in RBC, Hb, Hct, CK, CK-MB, and LDH levels, which should be caused by reoxygenation after hypoxia.

As one of the most common complications of diabetes, diabetic neuropathy often causes foot ulcers and even limb amputations. Inspite of continuous development in antidiabetic drugs, there is still no efficient therapy to cure diabetic neuropathy. Diabetic neuropathy shows declined vascularity in peripheral nerves and lack of angiogenic and neurotrophic factors. Mesenchymal stem cells (MSCs) have been indicated as a novel emerging regenerative therapy for diabetic neuropathy because of their multipotency. We will briefly review the pathogenesis of diabetic neuropathy, characteristic of MSCs, effects of MSC therapies for diabetic neuropathy and its related mechanisms. In order to treat diabetic neuropathy, neurotrophic or angiogenic factors in the form of protein or gene therapy are delivered to diabetic neuropathy, but therapeutic efficiencies are very modest if not ineffective. MSC treatment reverses manifestations of diabetic neuropathy. MSCs have an important role to repair tissue and to lower blood glucose level. MSCs even paracrinely secrete neurotrophic factors, angiogenic factors, cytokines, and immunomodulatory substances to ameliorate diabetic neuropathy. There are still several challenges in the clinical translation of MSC therapy, such as safety, optimal dose of administration, optimal mode of cell delivery, issues of MSC heterogeneity, clinically meaningful engraftment, autologous or allogeneic approach, challenges with cell manufacture, and further mechanisms.

Background Secreted phospholipase A2-IIA (sPLA2-IIA) is an inducible enzyme released under several inflammatory conditions. It has been shown that sPLA2-IIA is released from rat brain astrocytes after inflammatory stimulus, and lipopolysaccharide (LPS) and nitric oxide (NO) have been implicated in regulation of this release. Here, brain microvascular endothelial cells (BMVECs) were treated with LPS to uncover whether sPLA2-IIA was released, whether nitric oxide regulated this release, and any related signal mechanisms. Methods Supernatants were collected from primary cultures of BMVECs. The release of sPLA2-IIA, and the expression of inducible nitric oxide synthase (iNOS), phospho-JAK3, phospho-STAT1, total JAK3 and STAT1, β-actin, and bovine serum albumin (BSA) were analyzed by Western blot or ELISA. NO production was calculated by the Griess reaction. sPLA2 enzyme activity was measured with a fluorometric assay. Specific inhibitors of NO (L-NAME and aminoguanidine, AG), JAK3 (WHI-P154,WHI), STAT1 (fludarabine, Flu), and STAT1 siRNA were used to determine the involvement of these molecules in the LPS-induced release of sPLA2-IIA from BMVECs. Nuclear STAT1 activation was tested with the EMSA method. The monolayer permeability of BMVECs was measured with a diffusion assay using biotinylated BSA. Results Treatment of BMVECs with LPS increased the release of sPLA2-IIA and nitrite into the cell culture medium up to 24 h. Pretreatment with an NO donor, sodium nitroprusside, decreased LPS-induced sPLA2-IIA release and sPLA2 enzyme activity, and enhanced the expression of iNOS and nitrite generation after LPS treatment. Pretreatment with L-NAME, AG, WHI-P154, or Flu notably reduced the expression of iNOS and nitrite, but increased sPLA2-IIA protein levels and sPLA2 enzyme activity. In addition, pretreatment of the cells with STAT1 siRNA inhibited the phosphorylation of STAT1, iNOS expression, and nitrite production, and enhanced the release of sPLA2-IIA. Pretreatment with the specific inhibitors of NOS, JAK2, and STAT3 decreased the permeability of BMVECs. In contrast, inhibition of sPLA2-IIA release increased cell permeability. These results suggest that sPLA2-IIA expression is regulated by the NO-JAK3-STAT1 pathway. Importantly, sPLA2-IIA augmentation could protect the LPS-induced permeability of BMVECs. Conclusion Our results demonstrate the important action of sPLA2-IIA in the permeability of microvascular endothelial cells during brain inflammatory events. The sPLA2 and NO pathways can be potential targets for the management of brain MVEC injuries and related inflammation.

The proliferation of pulmonary artery smooth muscle cells (PASMCs) plays a role in pulmonary vascular remodeling (PVR). Recently, it was shown that vascular smooth muscular cell phenotype modulation is important for their proliferation in other diseases. However, little is known about the role of human PASMC phenotype modulation in the proliferation induced by hypoxia and its molecular mechanism during PVR. In this study, we found using primary cultured human PASMCs that hypoxia suppressed the expression of endogenous PKGIα, which was reversed by transfection with a recombinant adenovirus containing the full-length cDNA of PKGIα (Ad-PKGIα). Ad-PKGIα transfection significantly attenuated the hypoxia-induced downregulation of the expression of smooth muscle α-actin (SM-α-actin), myosin heavy chain (MHC) and calponin in PASMCs, indicating that hypoxia-induced phenotype modulation was blocked. Furthermore, flow cytometry and (3)H-TdR incorporation demonstrated that hypoxia-induced PASMC proliferation was suppressed by upregulation of PKGIα. These results suggest that enhanced PKGIα expression inhibited hypoxia-induced PASMC phenotype modulation and that it could reverse the proliferation of PASMCs significantly. Moreover, our previous work has demonstrated that Akt protein is activated in the process of hypoxia-induced proliferation of human PASMCs. Interestingly, we found that Akt was not activated by hypoxia when PASMC phenotype modulation was blocked by Ad-PKGIα. This result suggests that blocking phenotype modulation might be a key up-stream regulatory target.

This study examined the reduction of sepsis-induced ALI by inhibition of flagellin-stimulated TLR5 signaling.Rats were randomly divided into three groups: one group served as the sham-operated group (control group), and the other two groups received the induction of sepsis (sepsis and treatment groups). The treatment group was injected with anti-flagellin serum before induction of sepsis. At 2, 4, 6, 12, 24, and 48 h following induction of sepsis (six time-point subgroups, n = 10 per subgroup), arterial PaO(2), wet/dry (W/D) lung weight ratios, levels of serum and BALF flagellin and TNF-α, pulmonary pathological alterations, and TLR5 mRNA expression in the lungs were examined.Compared to sham-operated rats, septic rats had: increased levels of serum and BALF flagellin at 6, 12, 24, and 48 h; reduced arterial PaO(2); elevated W/D lung weight ratio; increased serum and BALF TNF-α levels; and up-regulated TLR5 mRNA expression at 12, 24, and 48 h (P0.01). Pretreatment with anti-flagellin serum, however, significantly inhibited sepsis-associated declines in arterial PaO(2), increased W/D lung weight ratios, elevated serum and BALF TNF-α levels, and up-regulated TLR5 mRNA expression at 24 and 48 h (P0.01).Neutralizing the actions of circulating flagellin with anti-flagellin serum delayed the development of ALI in rats with sepsis.

Single Ig IL-1 receptor-related molecule (SIGIRR) is one of the members of the Toll-like receptor (TLR)-IL-1 receptor superfamily. Previous studies demonstrated that SIGIRR can function as a negative regulator of IL-1 and LPS signaling. The purpose of this study was to evaluate the effect of enhanced expression of SIGIRR on LPS-induced acute lung injury. We constructed a recombinant adenoviral vector expressing murine SIGIRR (Ad.mSIGIRR) and a control adenoviral vector containing no transgene (Ad.V). A total of 4 × 10⁷ plaque-forming units of Ad.mSIGIRR or Ad.V adenoviral vector were administered intranasally to BALB/c mice. Forty-eight hours later, all the mice were administered a single dose of LPS via i.p. injection to induce lung injury. Lungs and blood were harvested at several time points. The expression of SIGIRR in lung, the histological changes in the lung, the levels of TNF-α in serum and lung, the concentration of nitric monoxide (NO) in lung, and the activity of myeloperoxidase and nuclear transcription factor κB in the lung were examined. A second cohort of mice was followed for survival for 7 days. Administration of Ad.mSIGIRR increased the expression of SIGIRR in lung tissue, as determined by reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry. Administration of Ad.mSIGIRR significantly suppressed the inflammatory reaction to LPS, attenuated the lung pathological changes, and improved the survival of mice, relative to a control adenovirus. These findings suggest that modulating the expression level of SIGIRR may be a promising potential treatment for acute lung injury.

J. Neurochem. (2010) 114, 1039–1048. Abstract Our previous studies show that group III secreted phospholipases A2 (sPLA2s III) induces extensive neuronal apoptosis in brain cortical cultures. However, the molecular mechanisms underlying sPLA2 III-induced neuronal injury/death are still unknown. Also it is not clear whether hypoxic pre-conditioning (HPC) is able to protect neurons from the sPLA2 III insult. In this report, we demonstrate that sPLA2 III significantly decreased production of Bcl-xl and the ratio of Bcl-xl/Bax, and increased expression of Bax, cleaved caspase 3, and cleaved α-Fodrin in primary neuronal culture. HPC prevented the sPLA2 III-induced decreases in production of Bcl-xl and the ratio of Bcl-xl/Bax, and increases in expression of Bax, cleaved caspase 3, and α-Fodrin. However, the HPC-produced neuronal protection was eliminated or attenuated by AG490, rapamycin, and STAT3 shRNA. Our results suggest that sPLA2 III-induced neuronal apoptosis is likely because of its alterations in expression and activity of Bcl-xl, Bax, caspase 3, and its target gene fodrin; and that HPC-produced neuroprotection against the sPLA2 III toxicity is mediated via JAK-STAT signal pathways that regulate the expression of Bcl-xl, Bax, and cleaved caspase 3 in cultured cortical neurons.

Objective To screen and identify two mimic epitopes in the inflammatory site of lipopolysaccharide binding protein (LBP), and to synthesize and purify their corresponding mimic epitope four branched peptide (multiple antigen peptide, MAP). Method Using an anti-full length LBP monoclonal antibody as the target molecule, the amino acid sequences of the exogenous peptides were deduced by combining several different techniques including: affinity screening of the phage display peptide library, the lipopolysaccharide (LPS) binding activity assay and competitive inhibition test, cytokine production inhibition, flow cytometry, and DNA sequencing. Basic Local Alignment Search Tool (BLAST) software was used to compare the resulting peptide sequences with the primary structure sequence of the LBP molecule, and thus the amino acid sequences for two mimic inflammatory epitopes for the binding of LBP and LPS were determined. Additionally, the two target sequences were coupled, and the 9-fluorenylmethyloxycarbonyl (FMOC) solid-phase synthesis method was used to synthesize the 24aa peptide. The design program of the multiple antigen peptide (MAP) was used to couple the four tandem peptides with lysine as the core base to produce the branch like structure, and thus, the four branched peptide was synthesized and purified. Results Fourteen phage clones (C) with competitive LPS binding activity with LBP were successfully obtained. Among these, the amino acid sequences of the peptides in C2, C19, C57, C77, C85 and C91 showed a homology of more than 90% to the primary structure of LBP. However, the amino acid sequences of C29 and C90, WKAQKRFMKKSG and LKTRKLFWKYKD, respectively, did not show homology to the primary structure of LBP, which were determined to be mimic epitopes of the inflammatory sites in LBP. Further synthesis of the 24aa peptide using FMOC solid-phase synthesis and MAP modification were carried out, the four branched peptide was synthesized and purified, and the purity was found to be higher than 95%. The purified peptide was subjected to mass spectrometry analysis and amino acid analysis, and its molecular weight (3102.77 kDa) and amino acid composition were in accordance with theoretical values. Conclusion The amino acid sequence for two mimic epitopes of the inflammatory site of LBP were determined to be WKAQKRFMKKSG and LKTRKLFWKYKD. The MAP was successfully prepared simultaneously and is able to be used as the core antigen protein for the formulation of vaccines. This knowledge will help in future investigations of the functional characteristics of LBP protein, and enhance exploration into new pathways for the prevention and treatment of LPS inflammatory diseases.

The study was aimed at screening out the mimetic peptides from the binding site of lipopolysaccharide binding protein and CD 14, and then observing if the mimetic peptide will inhibit in vitro LPS-induced inflammatory reaction and function as an anti-endotoxin in the model of LPS-induced acute lung injury.Human monocytic cell line (U937) was used in vitro. Thirty three-month-old SD rats were used. Phage display peptide library was adapted to screen mimetic peptide sequences.U937 cells were exposed to treatment with LPS and rhLBP and then were incubated with MP12 at three different concentrations after they were induced and differentiated by PMA. LPS intravenous injection was used to establish a model of rat acute lung injury which was later treated with intravenous injection of MP12.We successfully obtained the mimetic peptide of lipopolysaccharide-binding protein and CD 14 binding site, the gene sequence of which is FHRWPTWPLPSP (MP12). MP12 can markedly inhibit LPS induced TNF-alpha expression. MP12 can evidently increase PaO(2) of rats with acute lung injury and also increase the survival rate of these rats.MP12 (FHRWPTWPLPSP) has the same function as mimetic of lipopolysaccharide-binding protein and CD 14 binding site. The application of MP12, both in vitro and in vivo, confers the biological activity required to antagonise LBP/CD14 and block LPS inflammatory signals, and it can markedly enhance PaO(2) of rats suffering from acute lung injury and also enhance their survival rate.

SOCS3 is regarded as a major negative regulator of STAT3. Recent evidence indicates that SOCS3 regulates strength and duration of other signaling pathways including ras/ERK1/2/MAPK, PI3-K/Akt in non-malignant cells. The repression or silence of SOCS3 expression in a few tumor types has led to speculation that loss of SOCS3 gene is closely related to deregulation of multiple signal pathways during tumorigenesis. However, apart from STAT3, little is known in malignant cells about the mechanism by which SOCS3 modulates other intracellular signal cascades such as Erk1/2 and Akt, whose aberrant activation has been implicated in many human tumors. Expression of SOCS3 proved deficient in human lung adenocarcinoma A549 cells, and forced expression of SOCS3 resulted in growth inhibition. Growth suppression due to SOCS3 was associated with attenuated activation of Erk1/2, Akt as well as STAT3. The results suggested that SOCS3, as negative regulators of cytokine signaling, might maintain homeostasis by regulating multiple signaling pathways and reverse cell malignant behavior.

Summary Vaccination with allergen-encoding DNA has been proposed as having potential for allergen-specific immunotherapy. In this study, we examine the therapeutic effect of allergen-encoding DNA vaccination directly to dendritic cells (DCs) on allergen-induced allergic airway inflammation in a mouse model and explore potential mechanism. Ovalbumin (OVA)-sensitized and challenged mice were immunized with DNA vaccine and received bronchoalveolar lavage (BAL) 1 day after the last challenge, to measure BAL levels of interleukin (IL)-4, IL-5, interferon (IFN)-gamma and differential cell count. Pulmonary DCs and Spleen DCs were purified and sorted according to the expression of CD11c+CD80+ and CD11c+CD86+ co-stimulatory molecules. Our data demonstrated that DNA vaccine therapy with OVA-Fc-pcDNA3·1 significantly prevented OVA-increased levels of IL-4, IL-5 and the percentage of eosinophils and OVA-decreased level of IFN-gamma. OVA-Fc-pcDNA3·1-treated mice had less severity of airway inflammation, and lower expression of CD11c+CD80+ and CD11c+CD86+ on pulmonary DCs, as compared with animals with OVA-pcDNA3·1, pcDNA3·1 and OVA respectively. DNA vaccine encoding both Fc and OVA was shown to be more effective than DNA vaccine encoding OVA alone. Our data indicate that Fc-antigen combination-encoding DNA vaccination has better preventive effects on antigen-induced airway inflammation by regulating DCs, and may be a new alternative therapy for asthma.

Xanthine dehydrogenase/oxidase (XDH/XO) is associated with various pathological conditions related to the endothelial injury. However, the molecular mechanism underlying the activation of XDH/XO by hypoxia remains largely unknown. In this report, we determined whether the Janus kinases (JAKs) and signal transducers and activators of transcription (STATs) signaling pathway is involved in hypoxia-induced activation of XDH/XO in primary cultures of lung microvascular endothelial cells (LMVEC). We found that hypoxia significantly increased interleukin 6 (IL6) production in a time-dependent manner in LMVEC. Hypoxia also markedly augmented phosphorylation/activation of JAKs (JAK1, JAK2 and JAK3) and the JAK downstream effectors STATs (STAT3 and STAT5). Hypoxia-induced activation of STAT3 was blocked by IL6 antibodies, the JAK inhibitor AG490 and the suppressor of cytokine signaling 3 (SOCS3), implying that hypoxia-promoted IL6 secretion activates the JAK/STAT pathway in LMVEC. Phosphorylation and DNA-binding activity of STAT3 was also inhibited by the p38 MAPK inhibitor SB203580 and the phosphatidylinositol 3-kinase inhibitor LY294002, suggesting that multiple signaling pathways involved in STAT activation by hypoxia. Importantly, hypoxia promoted XDH/XO activation in LMVEC, which was markedly reversed by inhibiting the JAK/STAT pathway using IL6 antibodies, AG490 and SOCS3. These data demonstrated that JAKs, STATs and XDH/XO were sequentially activated by hypoxia. These data also provide the first evidence indicating that the JAK-STAT pathway is involved in hypoxia-mediated XDH/XO activation in LMVEC.

Pulmonary arterial smooth muscle cells (PASMC) were divided into a normoxic group (N), 2, 8 and 12 h hypoxic groups (H2, H8 and H12) and an AG490 plus 8 h hypoxic group (AG490). The expression of JAK1, JAK2, JAK3 and TYK2 mRNA was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). STAT1 and STAT3 protein expressions were determined by Western blotting. The results showed that the levels of JAK1, JAK2 and JAK3 mRNA did not change significantly in the N group but were increased after 2 h exposure to hypoxia. JAK1, JAK2 and JAK3 mRNA expressions peaked at 8 h. It decreased at 12 h but remained above those in the N group. TYK2 mRNA was not found in either hypoxic or normal PASMC. The phospho-STAT1 and -STAT3 protein levels increased after 2 h exposure to hypoxia. They were about 2.8 and 4.1 times the N group, respectively, after 8 h. They decreased at 12 h but remained above those in the N group. AG490 inhibited phospho-STAT3 protein expression by about 25.5% at 8 h but did not block the expression of phospho-STAT1 protein. These findings suggest that hypoxia induces the expression of JAK1, JAK2, JAK3 and phospho-STAT1 and -STAT3 in PASMC. Hypoxia activates the JAKs-STATs signaling pathway, which may participate in the pathogenesis of hypoxic PASMC injury.

Allergen-specific CD4+ T-helper (Th) 2 cells are involved in the induction and effector phase of allergic asthma. It is well established that T cells activation requires interaction of T cell receptor (TCR) and MHC–peptide complex, as well as costimulatory signal delivered by antigen presenting cells (APCs). There is increasing evidence that CD80 (B7.1) and CD86 (B7.2), as the most important costimulatory molecules, are involved in the allergic immune responses. In the present study, we investigated the CD80 and CD86 expression of spleen-derived dendritic cells (DCs) in a murine model of allergic asthma. We first established a murine model of ovalbumin (OVA)-allergic asthma that showed unique histological characteristic of allergic inflammation in the lung, high serum OVA-specific IgE level, high numbers of eosinophils in the bronchoalveolar lavage (BAL) and high production of Type 2 cytokines in the splenic T cells. In this model, we found that CD80 were significantly upregulated on the spleen-derived DCs from OVA-sensitized and challenged mice compared with that from PBS-treated or non-treated mice, while CD86 is not different among three groups. Furthermore, we demonstrated that Th2 immune responses were elicited by these DCs with high expression of CD80, even to naive T cells from non-treated mice. Our results suggest that DCs in the spleen of allergic mice, via upregulation of CD80 might play a pivotal role in the maintenance and amplification of allergic immune response, namely Th2 immune response.