WNT1-inducible signaling pathway protein 1 contributes to ventilator-induced lung injury

Effect of WISP1 on paraquat-induced EMT

BACKGROUND

Paraquat (PQ) can induce pulmonary fibrosis (PF) by modulating epithelial-mesenchymal transition (EMT) of alveolar epithelial cells, but the molecular mechanism is unknown. In this paper, the role of Wnt-inducible signaling protein-1 (WISP1) in PQ-induced EMT was inspected.

METHODS

The morphology, apoptosis, and mortality of A549 cells were observed through a microscope. The mRNA and protein levels of WISP1, E-cadherin, and Vimentin were confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot.

RESULTS

With the increase of PQ concentration, the morphology of A549 cells was apparently changed, cell apoptosis and mortality were enhanced. Besides, the E-cadherin abundance was reduced (p < 0.01), however, WISP1 and Vimentin contents were boosted after PQ treatment (p < 0.01). With the increase of PQ treatment time, the epithelial index of cells first increased and then decreased. The expression of WISP1 gene increased significantly with the increase of PQ treatment time (p < 0.01). Silence of WISP1 abolished the effect of PQ treatment on E-cadherin and Vimentin levels (p < 0.01). Downregulation of WISP1 curbed morphology change and PQ-induced EMT in A549 cells.

CONCLUSION

Knockdown of WISP1 inhibited PQ-induced EMT in A549 cells. This conclusion might provide a new therapeutic target for PQ poisoning treatment.

Characterization of acute lung injury in the bleomycin rat model

The aim of this study was to describe and characterize the pathophysiological changes occurring during the early inflammatory phase (first 3 days) in the rat bleomycin model of lung injury preceding the development of fibrosis. Further, we wanted to understand the kinetics and factors contributing to bleomycin-induced acute lung injury (ALI) and provide a robust, reliable and reproducible framework of features of ALI readouts to assess effects of therapeutics on bleomycin-induced ALI in rats. We induced ALI in rats with intratracheal (i.t.) installation of bleomycin. The animals were sacrificed on predetermined time points, that is, Day 0, 1, 2, and 3 post the bleomycin challenge. We analyzed bronchoalveolar lavage fluid (BALF) and lung tissue to establish and assess relevant experimental features of ALI. We demonstrated that bleomycin induced key features of experimental ALI including a profound increase in neutrophils in BALF (50-60%), pulmonary edema, and lung pathology on Day 3 after challenge. Furthermore, we showed that TGF-β1, IL-1β, TNF-α, IL-6, CINC-1, TIMP-1, and WISP-1 were induced by studying their kinetic profile during the first 3 days after bleomycin injury consistent with their known role ALI. We also confirmed that detectable fibrogenesis occurs at the earliest on Day 3 after injury based on collagen content, along with changes in the TGF-β/Smad signaling pathway and increased expression of Galectin-3, Vimentin, and Fibronectin in lung homogenate. Our report presents robust features and contributing mediators/factors to the pathology of bleomycin-induced ALI in rats on Day 3. The kinetic data provide insights on the progression of ALI and a detailed understanding of early events before actual fibrosis development. This set of experimental endpoints is very appropriate and invaluable for efficacy testing of potential novel therapeutic treatments (single or combined) in ALI and understanding their mechanism of action.

Optimal CCN4 Immunofluorescence for Tissue Microarray

CCN4 (also known as WNT1-Inducible Signaling Pathway Protein 1 or WISP1) is a 367 amino acid, 40 kDa protein located on chromosome 8q24.1-8q24.3. Prior studies have provided support for a pro-inflammatory role for CCN4. We have shown recently that CCN4 expression is associated with advanced disease, epithelial-mesenchymal transition, and an inflamed tumor microenvironment in multiple solid tumors. We detail here the CCN4 tissue microarray immunofluorescence protocol related to these findings.

Translational Role of Rodent Models to Study Ventilator-Induced Lung Injury

Mechanical ventilation is an important part of medical care in intensive care units and operating rooms to support respiration. While it is a critical component of medical care, it is well known that mechanical ventilation itself can be injurious to the lungs. Despite a large number of clinical and preclinical studies that have been done so far, there still exists a gap of knowledge regarding how to ventilate patients mechanically without increasing lung injury. Here, we will review what we have learned so far from preclinical and clinical studies and consider how to use preclinical models of ventilation-induced lung injury that better recapitulate the clinical scenarios.

Hepatic Wnt1 Inducible Signaling Pathway Protein 1 (WISP-1/CCN4) Associates with Markers of Liver Fibrosis in Severe Obesity

Liver fibrosis is a critical complication of obesity-induced fatty liver disease. Wnt1 inducible signaling pathway protein 1 (WISP1/CCN4), a novel adipokine associated with visceral obesity and insulin resistance, also contributes to lung and kidney fibrosis. The aim of the present study was to investigate the role of CCN4 in liver fibrosis in severe obesity. For this, human liver biopsies were collected from 35 severely obese humans (BMI 42.5 ± 0.7 kg/m², age 46.7 ± 1.8 y, 25.7% males) during bariatric surgery and examined for the expression of CCN4, fibrosis, and inflammation markers. Hepatic stellate LX-2 cells were treated with human recombinant CCN4 alone or in combination with LPS or transforming growth factor beta (TGF-β) and examined for fibrosis and inflammation markers. CCN4 mRNA expression in the liver positively correlated with BMI and expression of fibrosis markers COL1A1, COL3A1, COL6A1, αSMA, TGFB1, extracellular matrix turnover enzymes TIMP1 and MMP9, and the inflammatory marker ITGAX/CD11c. In LX-2 cells, the exposure to recombinant CCN4 caused dose-dependent induction of MMP9 and MCP1. CCN4 potentiated the TGF-β-mediated induction of COL3A1, TIMP1, and MCP1 but showed no interaction with LPS treatment. Our results suggest a potential contribution of CCN4 to the early pathogenesis of obesity-associated liver fibrosis.

WISP1 and TLR4 on Macrophages Contribute to Ventilator-Induced Lung Injury

Injurious mechanical ventilation has been shown to directly affect pulmonary and systemic immune responses. How these responses propagate or attenuate remains unknown. The goal of this study was to further determine whether toll-like receptor (TLR) 4 and WNT1-inducible signaling pathway protein 1 (WISP1) could contribute to injurious mechanical ventilation, especially focusing on the role of macrophages during experimental ventilator-induced lung injury. A prospective, randomized, and controlled animal study was designed, and male, wild-type (WT) C57BL/6 mice, TLR4 knockout (TLR4^-/-), and lyzTLR4 knockout (lyzTLR4^-/-) mice aging 8~12 weeks were used. Animals were anesthetized and randomized to spontaneous breathing (SB) group or to high tidal volume (VT, 20 ml/kg) mechanical ventilation (HTV) group. Histological evaluation, alveolar-capillary permeability of Evan's blue albumin (EBA), WISP1 protein levels, macrophage inflammatory protein-2 (MIP-2), and interleukin-6 (IL-6) in plasma and bronchoalveolar lavage fluid (BALF) concentrations were analyzed. HTV group was associated with a significant increase of WISP1 and EBA ratio in C57BL/6 mice, a significant decrease of WISP1 protein levels, and a significant decrease of IL-6, MIP-2 in plasma, and BALF concentrations of pro-inflammatory cytokines in TLR4^-/- and lyzTLR4^-/- knockout mice. In TLR4^-/- mice and lyzTLR4^-/- mice, there were also significant differences between SB group and HTV group in terms of H&E score and EBA ratio and level of pro-inflammation cytokines. The entire TLR4-targeted mice could further improve various inflammatory changes and damages when compared with lyzTLR4-targeted mice. What is more, TLR4^-/- mice and lyzTLR4^-/- mice reacted differently to rWISP1 and/or BMMC treated. TLR4^-/- mice had no response to rWISP1, while lyzTLR4^-/- mice still showed drastic response to both treatments. TLR4 and WISP1, especially the former one, on macrophages could contribute to releasing of pro-inflammatory cytokines during ventilator-induced lung injury. Injurious mechanical ventilation may result in an immune response which is similar to that of infection.

Mechanical Ventilation with Moderate Tidal Volume Exacerbates Extrapulmonary Sepsis-Induced Lung Injury via IL33-WISP1 Signaling Pathway

ABSTRACT

IL-33 and WNT1-inducible secreted protein (WISP1) play central roles in acute lung injury (ALI) induced by mechanical ventilation with moderate tidal volume (MTV) in the setting of sepsis. Here, we sought to determine the inter-relationship between IL-33 and WISP1 and the associated signaling pathways in this process.We used a two-hit model of cecal ligation puncture (CLP) followed by MTV ventilation (4 h 10 mL/kg) in wild-type, IL-33-/- or ST2-/- mice or wild-type mice treated with intratracheal antibodies to WISP1. Macrophages (Raw 264.7 and alveolar macrophages from wild-type or ST2-/- mice) were used to identify specific signaling components.CLP + MTV resulted in ALI that was partially sensitive to genetic ablation of IL-33 or ST2 or antibody neutralization of WISP1. Genetic ablation of IL-33 or ST2 significantly prevented ALI after CLP + MTV and reduced levels of WISP1 in the circulation and bronchoalveolar lung fluid. rIL-33 increased WISP1 in alveolar macrophages in an ST2, PI3K/AKT, and ERK dependent manner. This WISP1 upregulation and WNT β-catenin activation were sensitive to inhibition of the β-catenin/TCF/CBP/P300 nuclear pathway.We show that IL-33 drives WISP1 upregulation and ALI during MTV in CLP sepsis. The identification of this relationship and the associated signaling pathways reveals a number of possible therapeutic targets to prevent ALI in ventilated sepsis patients.

Network analysis of transcriptomics data for the prediction and prioritization of membrane-associated biomarkers for idiopathic pulmonary fibrosis (IPF) by bioinformatics approach

Idiopathic pulmonary fibrosis (IPF) is a rare yet crucial persistent lung disorder that actuates scarring of lung tissues, which makes breathing difficult. Smoking, environmental pollution, and certain viral infections could initiate lung scarring. However, the molecular mechanism involved in IPF remains elusive. To develop an efficient therapeutic arsenal against IPF, it is vital to understand the pathology and deviations in biochemical pathways that lead to disorder. In this study, we availed network analysis and other computational pipelines to delineate the prominent membrane proteins as diagnostic biomarkers and therapeutic targets for IPF. This study yielded a significant role of glycosaminoglycan binding, endothelin, and GABA-B receptor signaling pathway in IPF pathogenesis. Furthermore, ADCY8, CRH, FGB, GPR17, MCHR1, NMUR1, and SAA1 genes were found to be immensely involved with IPF, and the enrichment pathway analysis suggests that most of the pathways were corresponding to membrane transport and signal transduction functionalities. This analysis could help in better understanding the molecular mechanism behind IPF to develop an efficient therapeutic target or biomarkers for IPF.

Emerging role of CCN family proteins in fibrosis

Fibrosis is a common pathological change characterized by the excessive accumulation of fibrous connective tissue. Once uncontrolled, this pathological progress can lead to irreversible damage to the structure and function of organs, which is a serious threat to human health and life. Actually, the disability and death of patients caused by many chronic diseases have a closed relationship with fibrosis. The CCN protein family, including six members, is a small group of matrix proteins exhibiting structurally similar features. In the past 20 years, different biological functions of CCN proteins have been identified in various diseases. Of note, it has been recently shown that they are implicated in the key pathological process of fibrosis. In this review, we summarize the current status of knowledge regarding the role of CCN proteins involved in the pathogenesis of fibrosis diseases in detail. Furthermore, we highlight some of the underlying interaction mechanisms of CCN protein acting in fibrosis that helps to develop new drugs and determine appropriate clinical strategies for fibrotic diseases.

Adipokines: New Potential Therapeutic Target for Obesity and Metabolic, Rheumatic, and Cardiovascular Diseases

Besides its role as an energy storage organ, adipose tissue can be viewed as a dynamic and complex endocrine organ, which produces and secretes several adipokines, including hormones, cytokines, extracellular matrix (ECM) proteins, and growth and vasoactive factors. A wide body of evidence showed that adipokines play a critical role in various biological and physiological functions, among which feeding modulation, inflammatory and immune function, glucose and lipid metabolism, and blood pressure control. The aim of this review is to summarize the effects of several adipokines, including leptin, diponectin, resistin, chemerin, lipocalin-2 (LCN2), vaspin, omentin, follistatin-like 1 (FSTL1), secreted protein acidic and rich in cysteine (SPARC), secreted frizzled-related protein 5 (SFRP5), C1q/TNF-related proteins (CTRPs), family with sequence similarity to 19 member A5 (FAM19A5), wingless-type inducible signaling pathway protein-1 (WISP1), progranulin (PGRN), nesfatin-1 (nesfatin), visfatin/PBEF/NAMPT, apelin, retinol binding protein 4 (RPB4), and plasminogen activator inhibitor-1 (PAI-1) in the regulation of insulin resistance and vascular function, as well as many aspects of inflammation and immunity and their potential role in managing obesity-associated diseases, including metabolic, osteoarticular, and cardiovascular diseases.

Down-regulation of long non-coding RNA SNHG14 protects against acute lung injury induced by lipopolysaccharide through microRNA-34c-3p-dependent inhibition of WISP1

BACKGROUND

Accumulating evidence has shown the important roles of long non-coding RNAs (lncRNAs) in acute lung injury (ALI). This study aimed to investigate the potential role of lncRNA small nucleolar RNA host gene 14 (SNHG14) in lipopolysaccharides (LPS)-induced ALI.

METHODS

Expression of SNHG14, microRNA-34c-3p (miR-34c-3p) and Wnt1 inducible signaling pathway protein 1 (WISP1) in LPS-exposed mouse alveolar macrophages (MH-S) and lung tissues from mice with LPS-induced ALI was determined by reverse transcription quantitative polymerase chain reaction. The interactions among SNHG14, miR-34c-3p and WISP1 were analyzed by dual-luciferase reporter and RIP assays. Using gain-of-function or loss-of-function approaches, the contents of proinflammatory proteins were determined and MH-S cell viability was assessed to evaluate the in vitro functions of SNHG14, miR-34c-3p and WISP1, and wet/dry weight ratio and proinflammatory proteins in lung tissues were determined to assess their in vivo effects.

RESULTS

SNHG14 and WISP1 expression was increased, while miR-34c-3p was decreased in ALI models. SNHG14 bound to miR-34c-3p, resulting in impaired miR-34c-3p-dependent down-regulation of WISP1. Both SNHG14 silencing and miR-34c-3p over-expression reduced the levels of proinflammatory proteins IL-18, IL-1β, TNF-α and IL-6 and inhibited MH-S cell viability. SNHG14 silencing or miR-34c-3p over-expression decreased the wet/dry weight ratio in lung tissues from ALI mice. The reductions induced by SNHG14 silencing or miR-34c-3p over-expression were rescued by WISP1 over-expression.

CONCLUSION

This study demonstrated that lncRNA SNHG14 silencing alleviated inflammation in LPS-induced ALI through miR-34c-3p-mediated inhibition of WISP1. Our findings suggest that lncRNA SNHG14 may serve as a therapeutic target for ALI.

WISP1 is associated to advanced disease, EMT and an inflamed tumor microenvironment in multiple solid tumors

Background: WNT1-Inducible Signaling Pathway Protein 1 (WISP1) is implicated in prostate cancer growth and metastasis and the regulation of inflammation in diverse benign diseases. The objectives of this study were to assess the prognostic value of WISP1, its association to inflammation and its relevance as a biomarker for immune checkpoint blockade (ICB) response. Methods: Publicly available RNA-seq datasets were used to evaluate the prognostic value of WISP1 gene expression and its association with tumor-infiltrating lymphocytes, inflamed tumor microenvironment, and anti-PD-1 ICB response. A tissue microarray (TMA) including 285 radical prostatectomy specimens was used to confirm these associations in prostate cancer. The effect of recombinant WISP1 (rWISP1) on inflammatory cytokines was assessed in vitro. Results: High levels of WISP1 correlated with BCR-free survival in prostate adenocarcinoma and overall survival in primary melanoma, low-grade glioma, and kidney papillary cell carcinoma. Some effects could be accounted for by higher WISP1 expression in advanced disease. High WISP1 expression in prostate adenocarcinoma was correlated with CD8+ cells density. In vitro, rWISP1 increased inflammatory cytokine production. High WISP1 gene expression in RNA-seq datasets was correlated with gene signatures of multiple immune cell types as well as an inflammatory cytokine, immune checkpoint, and epithelial-mesenchymal transition (EMT) gene expression. WISP1 mRNA expression was associated with primary resistance to ICB in datasets showing EMT. Conclusions: Our results support an association between WISP1 expression and advanced disease, EMT and an inflamed tumor microenvironment in multiple solid tumors. The consequences of WISP1 expression on cancer immunotherapy remains to be addressed.

Non‑canonical Wnt signaling contributes to ventilator‑induced lung injury through upregulation of WISP1 expression

Mechanical ventilation may cause ventilator-induced lung injury (VILI). Canonical Wnt signaling has been reported to serve an important role in the pathogenesis of VILI. Bioinformatics analysis revealed that canonical and non-canonical Wnt signaling pathways were activated in VILI. However, the role of non-canonical Wnt signaling in the pathogenesis of VILI remains unclear. The present study aimed to analyze the potential role of non-canonical Wnt signaling in VILI pathogenesis. Lung injury was assessed via Evans blue albumin permeability and histological scoring, as well as by inflammatory cytokine expression and total protein concentration in bronchoalveolar lavage fluid. The relative protein expression of canonical and non-canonical Wnt signaling pathway components were examined via western blotting and immunohistochemistry. The results demonstrated that 6 h of mechanical ventilation at low tidal volume (LTV; 6 ml/kg) or moderate tidal volume (MTV; 12 ml/kg) induced lung injury in sensitive A/J mice. Ventilation with MTV increased the protein levels of Wnt-induced secreted protein 1 (WISP1), Rho-associated protein kinase 1 (ROCK1), phosphorylated (p)-Ras homolog gene family, member A and p-C-Jun N-terminal kinase (JNK). Inhibition of ROCK1 by Y27632 and JNK by SP600125 attenuated MTV-induced lung injury and decreased the expression of proteins involved in non-canonical Wnt signaling, including WISP1. In conclusion, non-canonical Wnt signaling participates in VILI by modulating WISP1 expression, which has been previously noted as critical for VILI development. Therefore, the non-canonical Wnt signaling pathway may provide a preventive and therapeutic target in VILI.

WISP1 mediates lung injury following hepatic ischemia reperfusion dependent on TLR4 in mice

BACKGROUND

Hepatic ischemia-reperfusion injury (IRI) is a common pathological phenomenon, which causes hepatic injury as well as remote organ injuries such as the lung. Several mediators, such as oxidative stress, Ca²⁺ overload and neutrophil infiltration, have been implied in the pathogenesis of liver and remote organ injuries following reperfusion. WNT1 inducible signaling pathway protein 1 (WISP1) is an extracellular matrix protein that has been associated with the onset of several malignant diseases. Previous work in our group has demonstrated WISP1 is upregulated and contributes to proinflammatory cascades in hepatic IRI. However, the role of WISP1 in the pathogenesis of lung injury after hepatic IRI still remains unknown.

METHODS

Male C57BL/6 mice were used to examine the expression and role of WISP1 in the pathogenesis of lung injuries after hepatic IRI and explore its potential mechanisms in mediating lung injuries.

RESULTS

We found WISP1 was upregulated in lung tissues following hepatic IRI. Treatment with anti-WISP1 antibody ameliorated lung injuries with alteration of cytokine profiles. Administration with rWISP1 aggravated lung injuries following hepatic IRI through excessive production of proinflammatory cytokines and inhibition of anti-inflammatory cytokines.

CONCLUSIONS

In this study, we concluded that WISP1 contributed to lung injuries following hepatic IRI through TLR4 pathway.

Mechanical ventilation enhances extrapulmonary sepsis-induced lung injury: role of WISP1-αvβ5 integrin pathway in TLR4-mediated inflammation and injury

Background

High tidal volume ventilation of healthy lungs or exacerbation of existing acute lung injury (ALI) by more moderate mechanical ventilation (MTV) produces ventilator-induced lung injury. It is less clear whether extrapulmonary sepsis sensitizes the lung to MTV.

Methods

We used a two-hit model of cecal ligation and puncture (CLP) followed 12 h later by MTV (10 ml/kg; 6 h) to determine whether otherwise noninjurious MTV enhances CLP-induced ALI by contrasting wildtype and TLR4^−/− mice with respect to: alveolar-capillary permeability, histopathology and intrapulmonary levels of WNT-inducible secreted protein 1 (WISP1) and integrin β5; plasma levels of cytokines and chemokines (TNF-α, IL-6, MIP-2, MCP-1) and intrapulmonary neutrophil infiltration; and other inflammatory signaling via intrapulmonary activation of JNK, p38 and ERK. A separate cohort of mice was pretreated with intratracheal neutralizing antibodies to WISP1, integrin β5 or IgG as control and the presented phenotyping repeated in a two-hit model; there were 10 mice per group in these first three experiments. Also, isolated peritoneal macrophages (PM) from wildtype and TLR4^−/−, MyD88^−/− and TRIF^−/− mice were used to identify a WISP1–TLR4–integrin β5 pathway; and the requisite role of integrin β5 in WISP1-induced cytokine and chemokine production in LPS-primed PM was examined by siRNA treatment.

Results

MTV, that in itself did not cause ALI, exacerbated increases in alveolar-capillary permeability, histopathologic scoring and indices of pulmonary inflammation in mice that previously underwent CLP; the effects of this two-hit model were abrogated in TLR4^−/− mice. Attendant with these findings was a significant increase in intrapulmonary WISP1 and integrin β5 in the two-hit model. Anti-WISP1 or anti-integrin β5 antibodies partially inhibited the two-hit phenotype. In PM, activation of TLR4 led to an increase in integrin β5 expression that was MyD88 and NF-κB dependent. Recombinant WISP1 increased LPS-induced cytokine release in PM that was inhibited by silencing either TLR4 or integrin β5.

Conclusions

These data show for the first time that otherwise noninjurious mechanical ventilation can exacerbate ALI due to extrapulmonary sepsis underscoring a potential interactive contribution of common events (sepsis and mechanical ventilation) in critical care, and that a WISP1–TLR4–integrin β5 pathway contributes to this phenomenon.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2237-0) contains supplementary material, which is available to authorized users.

Impacts of WNT1-inducible signaling pathway protein 1 polymorphism on hepatocellular carcinoma development

BACKGROUND

WNT1-inducible signaling pathway protein 1 (WISP1) is a member of CCN protein family and a downstream target of β-catenin. Aberrant WISP1 expression is associated with carcinogenesis. In the current study, we focused on examining WISP1 single nucleotide polymorphisms (SNPs) to elucidate hepatocellular carcinoma (HCC) clinicopathologic characteristics.

METHODOLOGY/PRINCIPAL FINDINGS

The WISP1 SNPs rs2977530, rs2977537, rs2929973, rs2929970, rs62514004, and rs16893344 were analyzed by real-time polymerase chain reaction in 332 patients with HCC and 664 cancer-free controls.

RESULTS

The patients with higher frequencies of WISP1 rs62514004 (AG + GG) and rs16893344 (CT + TT) variants revealed a lower risk to reach a later clinical stage compared with their wild-type carriers. Furthermore, individuals who carried WISP1 rs62514004 and rs16893344 haplotype G-T showed a greater synergistic effect combined with alcohol drinking on HCC development (AOR = 26.590, 95% CI = 9.780-72.295).

CONCLUSIONS

Our results demonstrated that the HCC patients with WISP1 SNPs are associated with HCC development, and WISP1 SNPs may serve as markers or therapeutic targets for HCC.

Neutrophil Extracellular Traps Are Pathogenic in Ventilator-Induced Lung Injury and Partially Dependent on TLR4

The pathogenesis of ventilator-induced lung injury (VILI) is associated with neutrophils. Neutrophils release neutrophil extracellular traps (NETs), which are composed of DNA and granular proteins. However, the role of NETs in VILI remains incompletely understood. Normal saline and deoxyribonuclease (DNase) were used to study the role of NETs in VILI. To further determine the role of Toll-like receptor 4 (TLR4) in NETosis, we evaluated the lung injury and NET formation in TLR4 knockout mice and wild-type mice that were mechanically ventilated. Some measures of lung injury and the NETs markers were significantly increased in the VILI group. DNase treatment markedly reduced NETs markers and lung injury. After high-tidal mechanical ventilation, the NETs markers in the TLR4 KO mice were significantly lower than in the WT mice. These data suggest that NETs are generated in VILI and pathogenic in a mouse model of VILI, and their formation is partially dependent on TLR4.

Cyclic stretch induced IL-33 production through HMGB1/TLR-4 signaling pathway in murine respiratory epithelial cells

Interleukin 33 (IL-33), an inflammatory and mechanically responsive cytokine, is an important component of a TLR4-dependent innate immune process in mucosal epithelium. Although TLR4 also plays a role in sensing biomechanical stretch, a pathway of stretch-induced TLR4-dependent IL-33 biosynthesis has not been revealed. In the current study, we show that short term (6 h) cyclic stretch (CS) of cultured murine respiratory epithelial cells (MLE-12) increased intracellular IL-33 expression in a TLR4 dependent fashion. There was no detectable IL-33 in conditioned media in this interval. CS, however, increased release of the notable alarmin, HMGB1, and a neutralizing antibody (2G7) to HMGB1 completely abolished the CS mediated increase in IL-33. rHMGB1 increased IL-33 synthesis and this was partially abrogated by silencing TLR4 suggesting additional receptors for HMGB1 are involved in its regulation of IL-33. Collectively, these data reveal a HMGB1/TLR4/IL-33 pathway in the response of respiratory epithelium to mechanical stretch.

Genetic variance is associated with susceptibility for cigarette smoke-induced DAMP release in mice

Chronic obstructive pulmonary disease (COPD) is characterized by unresolved neutrophilic airway inflammation and is caused by chronic exposure to toxic gases, such as cigarette smoke (CS), in genetically susceptible individuals. Recent data indicate a role for damage-associated molecular patterns (DAMPs) in COPD. Here, we investigated the genetics of CS-induced DAMP release in 28 inbred mouse strains. Subsequently, in lung tissue from a subset of strains, the expression of the identified candidate genes was analyzed. We tested whether small interfering RNA-dependent knockdown of candidate genes altered the susceptibility of the human A549 cell line to CS-induced cell death and DAMP release. Furthermore, we tested whether these genes were differentially regulated by CS exposure in bronchial brushings obtained from individuals with a family history indicative of either the presence or absence of susceptibility for COPD. We observed that, of the four DAMPs tested, double-stranded DNA (dsDNA) showed the highest correlation with neutrophilic airway inflammation. Genetic analyses identified 11 candidate genes governing either CS-induced or basal dsDNA release in mice. Two candidate genes ( Elac2 and Ppt1) showed differential expression in lung tissue on CS exposure between susceptible and nonsusceptible mouse strains. Knockdown of ELAC2 and PPT1 in A549 cells altered susceptibility to CS extract-induced cell death and DAMP release. In bronchial brushings, CS-induced expression of ENOX1 and ARGHGEF11 was significantly different between individuals susceptible or nonsusceptible for COPD. Our study shows that genetic variance in a mouse model is associated with CS-induced DAMP release, and that this might contribute to susceptibility for COPD.

TLR4 signaling induces TLR3 up-regulation in alveolar macrophages during acute lung injury

Acute lung injury is a life-threatening inflammatory response caused by severe infection. Toll-like receptors in alveolar macrophages (AMΦ) recognize the molecular constituents of pathogens and activate the host's innate immune responses. Numerous studies have documented the importance of TLR-TLR cross talk, but few studies have specifically addressed the relationship between TLR4 and TLR3. We explored a novel mechanism of TLR3 up-regulation that is induced by LPS-TLR4 signaling in a dose- and time-dependent manner in AMΦ from C57BL/6 mice, while the LPS-induced TLR3 expression was significantly reduced in TLR4^-/- and Myd88^-/- mice and following pretreatment with a NF-κB inhibitor. The enhanced TLR3 up-regulation in AMΦ augmented the expression of cytokines and chemokines in response to sequential challenges with LPS and Poly I:C, a TLR3 ligand, which was physiologically associated with amplified AMΦ-induced PMN migration into lung alveoli. Our study demonstrates that the synergistic effect between TLR4 and TLR3 in macrophages is an important determinant in acute lung injury and, more importantly, that TLR3 up-regulation is dependent on TLR4-MyD88-NF-κB signaling. These results raise the possibility that bacterial infections can induce sensitivity to viral infections, which may have important implications for the therapeutic manipulation of the innate immune system.

WISP1-αvβ3 integrin signaling positively regulates TLR-triggered inflammation response in sepsis induced lung injury

We recently noted that the matricellular protein WISP1 contributes to sepsis induced acute lung injury (ALI) via integrin β6. In the current study, we pursued further aspects of WISP1 modulation of TLR signaling in lungs of mice after sepsis and TLR4 mediated release of TNF-α in macrophages. After confirming that TLR4 and CD14 are critical in transducing sepsis mediated ALI, we now demonstrate that intrapulmonary αvβ3 is increased by polymicrobrial sepsis in a TLR4, CD14 dependent fashion. Comparison of cultured macrophages revealed that WISP1 increased release of TNF-α from RAW264.7 cells with baseline expression of αvβ3, but primary cultures of peritoneal macrophages (PMø) required activation of TLR4 to induce de novo synthesis of αvβ3 enabling WISP1 to stimulate release of TNF-α. The specific requirement for β3 integrin was apparent when the effect of WISP1 was lost in PMø isolated from β3(-/-) mice. WISP1 enhanced TLR4 mediated ERK signaling and U0126 (an ERK inhibitor) blocked LPS induced β3 integrin expression and WISP1 enhanced TNF-α release. Collectively these data suggest that WISP1-αvβ3 integrin signaling is involved in TLR4 pathways in macrophages and may be an important contributor to TLR4/CD14 mediated inflammation in sepsis induced lung injury.

Altered expression of the CCN genes in the lungs of mice in response to cigarette smoke exposure and viral and bacterial infections

The CCN proteins are key signaling and regulatory molecules involved in many biological functions and contribute to malignant and non-malignant lung diseases. Despite the high morbidity and mortality of the lung respiratory infectious diseases, there is very little data related to the expression of the CCNs during infection. We investigated in mice the pulmonary mRNA expression levels of five CCNs (1 to 5) in response to influenza A virus (IAV) and bacterial agents (Nontypeable Haemophilus influenzae (NTHi), lipopolysaccharide (LPS) and lipoteichoic acid (LTA)). IAV, NTHi, LPS or LTA were instilled intranasally into mice. Mice were also exposed for 4days or 8weeks to cigarette smoke alone or prior infection to IAV in order to determine if CS modifies the CCN response to a viral infection. All challenges induced a robust inflammation. The mRNA expression of CCN1, CCN2 and CCN3 was decreased after short exposure to CS whereas prolonged exposure altered the expression of CCN1, CCN3 and CCN4. Influenza A virus infection increased CCN1, 2, 4 and 5 mRNA levels but expression of CCN3 was significantly decreased. Acute CS exposure prior infection had little effect on the expression of CCN genes but prolonged exposure abolished the IAV-dependent induction. Treatment with LPS or LTA and infection with NTHi revealed that both Gram-positive and Gram-negative bacteria rapidly modulate the expression of the CCN genes. Our findings reveal that several triggers of lung inflammation influence differently the CCN genes. CCN3 deserves special attention since its mRNA expression is decreased by all the triggers studied.

Efficacy of Leukadherin-1 in the Prevention of Hyperoxia-Induced Lung Injury in Neonatal Rats

Lung inflammation plays a key role in the pathogenesis of bronchopulmonary dysplasia (BPD), a chronic lung disease of premature infants. The challenge in BPD management is the lack of effective and safe antiinflammatory agents. Leukadherin-1 (LA1) is a novel agonist of the leukocyte surface integrin CD11b/CD18 that enhances leukocyte adhesion to ligands and vascular endothelium and thus reduces leukocyte transendothelial migration and influx to the injury sites. Its functional significance in preventing hyperoxia-induced neonatal lung injury is unknown. We tested the hypothesis that administration of LA1 is beneficial in preventing hyperoxia-induced neonatal lung injury, an experimental model of BPD. Newborn rats were exposed to normoxia (21% O2) or hyperoxia (85% O2) and received twice-daily intraperitoneal injection of LA1 or placebo for 14 days. Hyperoxia exposure in the presence of the placebo resulted in a drastic increase in the influx of neutrophils and macrophages into the alveolar airspaces. This increased leukocyte influx was accompanied by decreased alveolarization and angiogenesis and increased pulmonary vascular remodeling and pulmonary hypertension (PH), the pathological hallmarks of BPD. However, administration of LA1 decreased macrophage infiltration in the lungs during hyperoxia. Furthermore, treatment with LA1 improved alveolarization and angiogenesis and decreased pulmonary vascular remodeling and PH. These data indicate that leukocyte recruitment plays an important role in the experimental model of BPD induced by hyperoxia. Targeting leukocyte trafficking using LA1, an integrin agonist, is beneficial in preventing lung inflammation and protecting alveolar and vascular structures during hyperoxia. Thus, targeting integrin-mediated leukocyte recruitment and inflammation may provide a novel strategy in preventing and treating BPD in preterm infants.

WISP1 mediates hepatic warm ischemia reperfusion injury via TLR4 signaling in mice

Wnt-induced secreted protein-1 (WISP1) is an extracellular matrix protein that has been reported in cancer researches. Our previous studies on WISP1 implied it could be a harmful mediator in septic mice. However, its role in liver ischemia reperfusion (I/R) injury is unknown. This study investigated the effects of WISP1 on liver I/R damage. Male C57BL/6 wild-type mice were used to undergo 60 min segmental (70%) ischemia. WISP1 expression was measured after indicated time points of reperfusion. Anti-WISP1 antibody was injected intraperitoneally to mice. Toll-like receptor 4 (TLR4) knockout mice and TIR-domain-containing adaptor inducing interferon-β (TRIF) knockout mice were adopted in this study. WISP1 was significantly enhanced after 6 h of reperfusion when compared with sham treated mice and significantly decreased either by TLR4 knockout mice or TRIF knockout mice. Anti-WISP1 antibody significantly decreased serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), pathological changes and pro-inflammatory cytokine levels in the mice following I/R. Furthermore, significantly increased serum transaminase levels were found in C57 wild-type mice treated with recombinant WISP1 protein, but not found in TLR4 knockout or TRIF knockout mice subjected to liver I/R. Taken together, WISP1 might contribute to hepatic ischemia reperfusion injury in mice and possibly depends on TLR4/TRIF signaling.

RGD peptides protects against acute lung injury in septic mice through Wisp1-integrin β6 pathway inhibition

Acute lung injury is a common consequence of sepsis, a life-threatening inflammatory response caused by severe infection. In this study, we elucidate the attenuating effects of synthetic Arg-Gly-Asp-Ser peptides (RGDs) on acute lung injury in a sepsis mouse model. We further reveal that the beneficial effects of RGDs stem from their negative regulation of the Wisp1 (WNT1-inducible signaling pathway)-integrin β6 pathway. After inducing sepsis using cecal ligation and puncture (CLP), mice were randomized into experimental and control groups, and survival rates were recorded over 7 days, whereas only 20% of mice subjected to CLP survived when compared with untreated controls; the addition of RGDs to this treatment regimen dramatically increased the survival rate to 80%. Histological analysis revealed acute lung injury in CLP-treated mice, whereas those subjected to the combined treatment of CLP and RGDs showed a considerable decrease in lung injury severity. The addition of RGDs also dramatically attenuated other common sepsis-associated effects, such as increased white blood cell number in bronchoalveolar lavage fluid and decreased pulmonary capillary barrier function. Furthermore, treatment with RGDs decreased the serum and bronchoalveolar lavage fluid levels of inflammatory cytokines such as tumor necrosis factor α and interleukin 6, contrary to the CLP treatment alone that increased the levels of these proteins. Interestingly, however, RGDs had no detectable effect on bacterial invasion following sepsis induction. In addition, mice treated with RGDs showed decreased levels of wisp1 and integrin β6 when compared with CLP-treated mice. In the present study, a linkage between Wisp1 and integrin β6 was evaluated in vivo. Most strikingly, RGDs resulted in a decreased association of Wisp1 with integrin β6 based on coimmunoprecipitation analyses. These data suggest that RGDs ameliorate acute lung injury in a sepsis mouse model by inhibiting the Wisp1-integrin β6 pathway.

MECHANICAL VENTILATION AUGMENTS POLY(I:C)INDUCED LUNG INJURY VIA A WISP1-INTEGRIN β3 DEPENDENT PATHWAY IN MICE

Mechanical ventilation can improve hypoxemia, but can also cause the so-called ventilator-induced lung injury (VILI). Polyinosinic-polycytidylic acid (poly(I:C)), an analogue of natural double strand RNA virus, can induce lung inflammation. The purpose of this study was to determine whether moderate tidal volume mechanical ventilation (MTV) augments Poly(I:C)-induced lung injury, and if so, the mechanism responsible for it. Poly(I:C) (2μg/g) were instilled intratracheally in C57BL/6J wide type (WT) mice. They were then randomized to MTV (10ml/kg tidal volume) or spontaneous breath. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected 4h later for various measurements. Our results showed that MTV did not cause significant injury in normal lungs, but augmented Poly(I:C)-induced lung injury. The expression level of WNT-induced secreted protein 1 (WISP1) was consistent with lung injury, and the amplification of lung injury by MTV can be alleviated by anti-WISP1 antibody treatment. MTV further increased Poly(I:C)-induced integrin β3 expression in the lung. And co-immunoprecipitation (Co-IP) results suggested there was an interaction between WISP1 and β3. WISP1 significantly increased Poly(I:C)-induced TNF-α production in macrophages isolated from WT mice but not in macrophages isolated from β3 knock-out mice. Co-treatment with WISP1 and Poly(I:C) markedly increased the phosphorylation of extracellular signal-related kinase (ERK) in macrophages. Pretreating macrophages with an ERK inhibitor, U0126, dose-dependently antagonized WISP's synergistic effect on Poly(I:C)-induced TNF-α release. In conclusion, MTV exaggerates Poly(I:C)-induced lung injury in a WISP1 and integrin β3 dependent manner, involving, at least part, the activation of the ERK pathway. The WISP1-integrin β3 pathway could be an important target for novel therapy.

Genetic variation associates with susceptibility for cigarette smoke-induced neutrophilia in mice

Neutrophilic airway inflammation is one of the major hallmarks of chronic obstructive pulmonary disease and is also seen in steroid resistant asthma. Neutrophilic airway inflammation can be induced by different stimuli including cigarette smoke (CS). Short-term exposure to CS induces neutrophilic airway inflammation in both mice and humans. Since not all individuals develop extensive neutrophilic airway inflammation upon smoking, we hypothesized that this CS-induced innate inflammation has a genetic component. This hypothesis was addressed by exposing 30 different inbred mouse strains to CS or control air for 5 consecutive days, followed by analysis of neutrophilic lung inflammation. By genomewide haplotype association mapping, we identified four susceptibility genes with a significant association to lung tissue levels of the neutrophil marker myeloperoxidase under basal conditions and an additional five genes specifically associated with CS-induced tissue MPO levels. Analysis of the expression levels of the susceptibility genes by quantitative RT-PCR revealed that three of the four genes associated with CS-induced tissue MPO levels had CS-induced changes in gene expression levels that correlate with CS-induced airway inflammation. Most notably, CS exposure induces an increased expression of the coiled-coil domain containing gene, Ccdc93, in mouse strains susceptible for CS-induced airway inflammation whereas Ccdc93 expression was decreased upon CS exposure in nonsusceptible mouse strains. In conclusion, this study shows that CS-induced neutrophilic airway inflammation has a genetic component and that several genes contribute to the susceptibility for this response.

Association of Wnt-Inducible Signaling Pathway Protein 1 Genetic Polymorphisms With Lung Cancer Susceptibility and Platinum-Based Chemotherapy Response

BACKGROUND

Platinum-based chemotherapy is the main treatment method for lung cancer patients. The genetic polymorphisms of Wnt-inducible signaling pathway protein 1 (WISP1) were reported to be associated with the development of diverse lung diseases. In this study, we aimed to investigate the relationship of WISP1 genetic polymorphisms with lung cancer susceptibility and platinum-based chemotherapy response in Chinese lung cancer patients.

MATERIALS AND METHODS

A total of 556 lung cancer patients and 254 healthy controls were enrolled onto this study. The 28 polymorphisms of the WISP1 gene were genotyped by the Sequenom MassARRAY system.

RESULTS

We found that WISP1 rs16893344, rs2977530, rs2977537, and rs62514004 (P = .009, .033, .049, and .036, respectively) polymorphisms were related to susceptibility of lung cancer; and WISP1 rs11778573 (P = .023, nonsmokers), rs16893344 (P = .013, ≥ 50 years old), rs2977536 (P = .039, ≥ 50 years old; P = .044, nonsmokers; P = .047, non-small-cell lung cancer, respectively), rs2977549 (P = .013, smokers), and rs62514004 (P = .033, ≥ 50 years old) polymorphisms were significantly associated with platinum-based chemotherapy response in lung cancer patients.

CONCLUSION

Genotypes of WISP1 may be novel and useful biomarkers for diagnosis of lung cancer and evaluation of platinum-based chemotherapy response in lung cancer patients.

WISP1 polymorphisms contribute to platinum-based chemotherapy toxicity in lung cancer patients

Platinum-based chemotherapy toxicity is always one of the serious problems from which lung cancer patients suffer. The genetic polymorphism of WISP1 was revealed to be associated with susceptibility and platinum-based chemotherapy response in our previous studies. In this study, we aimed to investigate the relationship of WISP1 genetic polymorphisms with platinum-based chemotherapy toxicity in lung cancer patients. A total of 412 lung cancer patients were enrolled in this study, and 28 polymorphisms of the WISP1 gene were genotyped by SequenomMassARRAY. We found that WISP1 polymorphisms (rs2929965, rs2929969, rs2929970, rs2929973 and rs754958) were related to the overall chemotherapy toxicity of lung cancer in subgroup analyses. Rs16904853, rs2929970, rs2977549 and rs2977551 (p = 0.021, 0.028, 0.024, 0.048, respectively) polymorphisms were significantly associated with hematologic toxicity. Rs2929946, rs2929970, rs2977519, rs2977536, rs3739262 and rs754958 (p = 0.031, 0.046, 0.029, 0.016, 0.042, 0.035, respectively) polymorphisms were significantly associated with the gastrointestinal toxicity of lung cancer. Genotypes of WISP1 may be novel and useful biomarkers for predicting platinum-based chemotherapy toxicity in lung cancer patients.

miR-92a regulates TGF-β1-induced WISP1 expression in pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most common and fatal form of idiopathic interstitial pneumonia. MicroRNAs (miRNAs), short, single-stranded RNAs that regulate protein expression in a post-transcriptional manner, have recently been demonstrated to contribute to IPF pathogenesis. We have previously identified WNT1-inducible signaling pathway protein 1 (WISP1) as a highly expressed pro-fibrotic mediator in IPF, but the underlying mechanisms resulting in increased WISP1 expression, remain elusive. Here, we investigated whether WISP1 is a target of miRNA regulation. We applied a novel supervised machine learning approach, which predicted miR-30a/d and miR-92a target sites in regions of the human WISP1 3'UTR preferentially bound by the miRNA ribonucleoprotein complex. Both miRNAs were decreased in IPF samples, whereas WISP1 protein was increased. We demonstrated further that transforming growth factor (TGF)-β1-induced WISP1 expression in primary lung fibroblasts in vitro and lung homogenates in vivo. Notably, miR-30a and miR-92a reversed TGF-β1-induced WISP1 mRNA expression in lung fibroblasts. Moreover, miR-92a inhibition increased WISP1 protein expression in lung fibroblasts. An inverse relationship for WISP1 and miR-92a was found in a TGF-β1 dependent lung fibrosis model in vivo. Finally, we found significantly increased WISP1 expression in primary IPF fibroblasts, which negatively correlated with miR-92a level ex vivo. Altogether, our findings indicate a regulatory role of miR-92a for WISP1 expression in pulmonary fibrosis.

Role of β-catenin-regulated CCN matricellular proteins in epithelial repair after inflammatory lung injury

Repair of the lung epithelium after injury is integral to the pathogenesis and outcomes of diverse inflammatory lung diseases. We previously reported that β-catenin signaling promotes epithelial repair after inflammatory injury, but the β-catenin target genes that mediate this effect are unknown. Herein, we examined which β-catenin transcriptional coactivators and target genes promote epithelial repair after inflammatory injury. Transmigration of human neutrophils across cultured monolayers of human lung epithelial cells resulted in a fall in transepithelial resistance and the formation of discrete areas of epithelial denudation ("microinjury"), which repaired via cell spreading by 96 h. In mice treated with intratracheal (i.t.) LPS or keratinocyte chemokine, neutrophil emigration was associated with increased permeability of the lung epithelium, as determined by increased bronchoalveolar lavage (BAL) fluid albumin concentration, which decreased over 3-6 days. Activation of β-catenin/p300-dependent gene expression using the compound ICG-001 accelerated epithelial repair in vitro and in murine models. Neutrophil transmigration induced epithelial expression of the β-catenin/p300 target genes Wnt-induced secreted protein (WISP) 1 and cysteine-rich (Cyr) 61, as determined by real-time PCR (qPCR) and immunostaining. Purified neutrophil elastase induced WISP1 upregulation in lung epithelial cells, as determined by qPCR. WISP1 expression increased in murine lungs after i.t. LPS, as determined by ELISA of the BAL fluid and qPCR of whole lung extracts. Finally, recombinant WISP1 and Cyr61 accelerated repair, and Cyr61-neutralizing antibodies delayed repair of the injured epithelium in vitro. We conclude that β-catenin/p300-dependent expression of WISP1 and Cyr61 is critical for epithelial repair and represents a potential therapeutic target to promote epithelial repair after inflammatory injury.