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NEW FINDINGS What is the central question of this study? In this study, by using motor vehicle exhaust (MVE) exposure with or without lipopolysaccharide (LPS) instillation, we established, evaluated and compared MVE, LPS and MVE+LPS treatment-induced chronic obstructive pulmonary disease (COPD) models in mice. What is the main finding and its importance? Our study demonstrated that the combination of chronic exposure to MVE with early LPS instillation can establish a mouse model with some features of COPD, which will allow researchers to investigate the underlying molecular mechanisms linking air pollution and COPD pathogenesis. ABSTRACT Although it is well established that motor vehicle exhaust (MVE) has a close association with the occurrence and exacerbation of chronic obstructive pulmonary disease (COPD), very little is known about the combined effects of MVE and intermittent or chronic subclinical inflammation on COPD pathogenesis. Therefore, given the crucial role of inflammation in the development of COPD, we wanted to establish an animal model of COPD using both MVE exposure and airway inflammation, which could mimic the clinical pathological changes observed in COPD patients and greatly benefit the study of the molecular mechanisms of COPD. In the present study, we report that mice undergoing chronic exposure to MVE and intratracheal instillation of lipopolysaccharide (LPS) successfully established COPD, as characterized by persistent air flow limitation, airway inflammation, inflammatory cytokine production, emphysema and small airway remodelling. Moreover, the mice showed significant changes in ventricular and vascular pathology, including an increase in right ventricular pressure, right ventricular hypertrophy and remodelling of pulmonary arterial walls. We have thus established a new mouse COPD model by combining chronic MVE exposure with early intratracheal instillation of LPS, which will allow us to study the relationship between air pollution and the development of COPD and to investigate the underlying molecular mechanisms.

Previously, we and others have demonstrated that activation of peroxisome proliferator-activated receptor γ (PPARγ) by specific pharmacological agonists inhibits the pathogenesis of chronic hypoxia-induced pulmonary hypertension (CHPH) by suppressing the proliferation and migration in distal pulmonary arterial smooth muscle cells (PASMCs). Moreover, these beneficial effects of PPARγ are mediated by targeting the intracellular calcium homeostasis and store-operated calcium channel (SOCC) proteins, including the main caveolae component caveolin-1. However, other than the caveolin-1 targeted mechanism, in this study, we further uncovered a caveolin-1 dependent mechanism within the activation of PPARγ by the specific agonist GW1929. First, effective knockdown of caveolin-1 by small-interfering RNA (siRNA) markedly abolished the upregulation of GW1929 on PPARγ expression at both mRNA and protein levels; Then, in HEK293T, which has previously been reported with low endogenous caveolin-1 expression, exogenous expression of caveolin-1 significantly enhanced the upregulation of GW1929 on PPARγ expression compared with nontransfection control. In addition, inhibition of PPARγ by either siRNA or pharmacological inhibitor T0070907 led to increased phosphorylation of cellular mitogen-activated protein kinases ERK1/2 and p38. In parallel, GW1929 dramatically decreased the expression of the proliferative regulators (cyclin D1 and PCNA), whereas it increased the apoptotic factors (p21, p53, and mdm2) in hypoxic PASMCs. Furthermore, these effects of GW1929 could be partially reversed by recovery of the drug treatment. In combination, PPARγ activation by GW1929 reversibly drove the cell toward an antiproliferative and proapoptotic phenotype in a caveolin-1-dependent and -targeted mechanism.

Store‑operated calcium entry (SOCE) is critical for regulating the proliferation and metastasis of various cancer types. The present study aimed to investigate the role of SOCE on nicotine‑promoted proliferation of non‑small cell lung cancer (NSCLC) A549 cells. Cell proliferation was evaluated by BrdU incorporation assay. The SOCE and basal [Ca2+]i in NSCLC A549 cells were determined using Fura‑2 fluorescence microscopy. The mRNA and protein expression levels were determined by real‑time quantitative PCR and western blotting, respectively. The results demonstrated that, in A549 cells, the detectable store‑operated calcium channel (SOCC) components were TRPC proteins 1, 3, 4 and 6 and Orail, among which TRPC1, TRPC6 and Orai1 are expressed at relatively high levels with TRPC3 and TRPC4 at relatively low levels. Nicotine upregulated the mRNA and protein expression of TRPC1, TRPC6 and Orai1, increased basal [Ca2+]i and enhanced SOCE. Promotion of cell proliferation but not migration was observed in the nicotine‑treated cells, which was inhibited by SOCE inhibitor SKF‑96365. Furthermore, nicotine upregulated HIF‑1α expression in the A549 and NCI‑H292 cells. Silencing of HIF‑1α abrogated the increases in TRPCs and Orail and reversed the increases in basal [Ca2+]i and SOCE. Meanwhile, suppression of proliferation was observed in cells following HIF‑1α silencing. In conclusion, the results indicate that nicotine promotes lung cancer cell proliferation likely by upregulating HIF‑1α and SOCC components and therefore enhancing SOCE and increasing basal [Ca2+]i.

Many deltas are likely undergoing net erosion because of rapid decreases in riverine sediment supply and rising global sea levels. However, detecting erosion in subaqueous deltas is usually difficult because of the lack of bathymetric data. In this study, by comparing bathymetric data between 1981 and 2012 and surficial sediment grain sizes from the Yangtze subaqueous delta front over the last three decades, we found severe erosion and significant sediment coarsening in recent years since the construction of Three Gorges Dam (TGD), the largest dam in the world. We attributed these morphological and sedimentary variations mainly to the human-induced drastic decline of river sediment discharge. Combined with previous studies based on bathymetric data from different areas of the same delta, we theorize that the Yangtze subaqueous delta is experiencing overall (net) erosion, although local accumulation was also noted. We expect that the Yangtze sediment discharge will further decrease in the near future because of construction of new dams and delta recession will continue to occur.

Bone morphogenetic protein 4 (BMP4) is a multifunctional growth factor that belongs to the TGF-β superfamily. The role of BMP4 in lung diseases is not fully understood. Here, we demonstrate that BMP4 was upregulated in lungs undergoing lipopolysaccharide (LPS)-induced inflammation, and in airway epithelial cells treated with LPS or TNF-α. BMP4 mutant (BMP4(+/-) ) mice presented with more severe lung inflammation in response to LPS or Pseudomonas aeruginosa, and lower bacterial load compared with that in BMP4(+/+) mice. Knockdown of BMP4 by siRNA increased LPS and TNF-α-induced IL-8 expression in 16HBE human airway epithelial cells and in primary human bronchial epithelial cells. Similarly, peritoneal macrophages from BMP4(+/-) mice produced greater levels of TNF-α and keratinocyte chemoattractant (KC) upon LPS treatment compared with cells from BMP4(+/+) mice. Administration of exogenous BMP4 attenuated the upregulation of TNF-α, IL-8, or KC induced by LPS and/or TNF-α in airway epithelial cells, and peritoneal macrophages. Finally, partial deficiency of BMP4 in BMP4(+/-) mice protected the animals from restrictive lung function reduction upon chronic LPS exposure. These results indicate that BMP4 plays an important anti-inflammatory role, controlling the strength and facilitating the resolution of acute lung inflammation; yet, BMP4 also contributes to lung function impairment during chronic lung inflammation.

This study investigated the gasification of wood, weed, plastic, tire, carton and their mixtures using zeolite (A4 type) as a catalyst, with the purpose of investigating the potential interactions of the various feedstocks during gasification. The co-gasification of the mixed feedstock led to the occurrences of the cross-interactions, which substantially impacted the distribution of the products in gasification. During the co-gasification, the pyrolysis/gasification of the different feedstocks produced the reaction intermediates with varied structures that interacted with each other and with the char formed from the different feedstock. The interaction could promote the gasification of the tarry compounds into gaseous products, which could also promote the gasification of the char to lower the char yields. Further to this, the cross-polymerisation or cracking of the varied reaction intermediates also took place during the co-gasification, leading to the formation of more coke deposits on catalyst. The co-gasification of the mixed feedstocks significantly impacted the reaction network, impacting the formation of gases, tar, char and the coke on catalysts, originating from the cross-interaction among the reaction intermediates derived from the pyrolysis/gasification of the various feedstocks.

Long non-coding RNAs (lncRNAs) have critical regulatory roles in protein-coding gene expression. Aberrant expression profiles of lncRNAs have been observed in various human diseases. In this study, we investigated transcriptome profiles in lung tissues of chronic cigarette smoke (CS)-induced COPD mouse model. We found that 109 lncRNAs and 260 mRNAs were significantly differential expressed in lungs of chronic CS-induced COPD mouse model compared with control animals. GO and KEGG analyses indicated that differentially expressed lncRNAs associated protein-coding genes were mainly involved in protein processing of endoplasmic reticulum pathway, and taurine and hypotaurine metabolism pathway. The combination of high throughput data analysis and the results of qRT-PCR validation in lungs of chronic CS-induced COPD mouse model, 16HBE cells with CSE treatment and PBMC from patients with COPD revealed that NR_102714 and its associated protein-coding gene UCHL1 might be involved in the development of COPD both in mouse and human. In conclusion, our study demonstrated that aberrant expression profiles of lncRNAs and mRNAs existed in lungs of chronic CS-induced COPD mouse model. From animal models perspective, these results might provide further clues to investigate biological functions of lncRNAs and their potential target protein-coding genes in the pathogenesis of COPD.

Pulmonary arterial hypertension (PAH) is a progressive pulmonary vasculopathy with significant morbidity and mortality. Bone morphogenetic protein receptor type 2 (BMPR2) has been well recognized as the principal gene responsible for heritable and sporadic PAH. Four unrelated Chinese patients with PAH and their family members, both symptomatic and asymptomatic, were genetically evaluated by sequencing all exons and the flanking regions of BMPR2. Functionality of the aberrant mutations at the 5' untranslated region (UTR) of BMPR2 in the families with PAH was determined by site mutation, transient transfection, and promoter-reporter assays. Four individual mutations in the BMPR2 gene were identified in the 4 families, respectively: 10-GGC repeats, 13-GGC repeats, 4-AGC repeats in 5'UTR, and a novel missense mutation in exon 7 (c.961C>T; p.Arg321X). Moreover, we demonstrated that (1) these 5'UTR mutations decreased the transcription of BMPR2 and (2) the GGC repeats and AGC repeats in BMPR2 5'UTR bore functional binding sites of EGR-1 and MYF5, respectively. This is the first report demonstrating the presence of functional BMPR2 5'UTR mutations in familial patients with PAH and further indicating that EGR-1 and MYF5 are potential targets for correcting these genetic abnormalities for PAH therapy.

Bone morphogenetic protein 4 (BMP4) is a multifunctional growth factor that belongs to the TGF-β superfamily. The role of BMP4 in lung diseases is not fully understood. Here, we demonstrate that BMP4 was upregulated in lungs undergoing lipopolysaccharide (LPS)-induced inflammation, and in airway epithelial cells treated with LPS or TNF-α. BMP4 mutant (BMP4(+/-) ) mice presented with more severe lung inflammation in response to LPS or Pseudomonas aeruginosa, and lower bacterial load compared with that in BMP4(+/+) mice. Knockdown of BMP4 by siRNA increased LPS and TNF-α-induced IL-8 expression in 16HBE human airway epithelial cells and in primary human bronchial epithelial cells. Similarly, peritoneal macrophages from BMP4(+/-) mice produced greater levels of TNF-α and keratinocyte chemoattractant (KC) upon LPS treatment compared with cells from BMP4(+/+) mice. Administration of exogenous BMP4 attenuated the upregulation of TNF-α, IL-8, or KC induced by LPS and/or TNF-α in airway epithelial cells, and peritoneal macrophages. Finally, partial deficiency of BMP4 in BMP4(+/-) mice protected the animals from restrictive lung function reduction upon chronic LPS exposure. These results indicate that BMP4 plays an important anti-inflammatory role, controlling the strength and facilitating the resolution of acute lung inflammation; yet, BMP4 also contributes to lung function impairment during chronic lung inflammation.

The anti-inflammatory function of tanshinone IIA (TIIA), an active natural compound from Chinese herbal medicine Danshen, has been well recognized, and therefore TIIA has been widely used to treat various inflammatory conditions associated with cardiac and lung diseases. Mucin 1 (Muc1) plays important anti-inflammatory roles in resolution of acute lung inflammation. In this study, we investigated the effects of TIIA on LPS-induced acute lung inflammation, as well as its relationship to Muc1 expression in mouse lung and MUC1 in human alveolar epithelial cells. TIIA pretreatment significantly inhibited LPS-induced pulmonary inflammation in both Muc1 wild-type ( Muc1+/+) and knockout ( Muc1−/−) mice, as manifested by reduced neutrophil infiltration and reduced TNF-α and keratinocyte chemoattractant levels in bronchoalveolar lavage fluid. The inhibitory effects of TIIA on airway inflammation were associated with reduced expression of Muc1 in Muc1+/+ mouse lung. Moreover, pretreatment with TIIA significantly inhibited LPS-induced MUC1 expression and TNF-α release in A549 alveolar epithelial cells. TNF-α upregulated MUC1 mRNA and protein expression in A549 cells, which was inhibited by pretreatment with TIIA. The LPS-induced MUC1 expression was blocked when A549 cells were transfected with siRNA targeting for TNF-α receptor 1. Furthermore, TIIA inhibited LPS-induced nuclear translocation of NF-κB and upregulation of Toll-like receptor 4 in A549 cells. Taken together, these results demonstrate that TIIA suppressed LPS-induced acute lung inflammation regardless of the presence of Muc1, and TIIA inhibited LPS- and TNF-α-induced MUC1/Muc1 expression in airway epithelial cells, suggesting that MUC1/Muc1 does not account for the mechanisms of the anti-inflammatory effects of TIIA in the airway.

Conventional chemotherapy and radiation therapy against non-small cell lung cancer (NSCLC) are relatively insensitive and unsatisfactory. Para-toluenesulfonamide (PTS), a unique antitumor drug for local intratumoral injection, shows an efficacy of severely suppressing solid tumor growth with mild side effects in clinical trials. The aim of this study was to investigate the effect of PTS on lung cancer H460 cells in vivo in nude mice and its underlying mechanisms in vitro.A lung cancer model for in vivo experiment was established in BALB/c nude mice using H460 cells to examine the effect of local injection of PTS on tumor suppression. We also assessed the injury to the normal tissue by subcutaneous injection of PTS. In vitro, PTS was diluted into different doses for study on its antitumor mechanisms. We evaluated the necrotic effect of PTS on H460 cells by PI and Hoechst 33342 staining. Cell viability and membrane permeability were also determined by using CCK-8 and LDH assays respectively. All these tests were conducted in comparison with traditional local injection of anhydrous ethanol.PTS was shown to significantly inhibit the growth of H460 tumor xenografts in nude mice by inducing necrosis of the tumor histologically. Its effect on tumor growth was significantly stronger than that of anhydrous ethanol. By contrast, the injured normal tissue by PTS injection was less than that by ethanol. In vitro, PTS still demonstrated excellent necrotizing effect on H460 cells when diluted to a lower concentration. Detailed analysis of PTS on H460 cells indicated that PTS had a better effect on attenuating the cell viability and increasing the cell membrane permeability than ethanol at the same level.PTS exhibits excellent inhibition effect on the growth of lung cancer by necrotizing tumor in vivo and in vitro, reducing tumor cell viability and augmenting the membrane permeability in vitro, with only mild injury to normal tissue. The antitumor effect of PTS on lung cancer in vivo and in vitro is stronger than that of ethanol.