Fibulin-1 regulates the pathogenesis of tissue remodeling in respiratory diseases

Spatiotemporally cascade-driven "Lipomicelles" enhance extracellular matrix penetration and remodel intercellular crosstalk in pulmonary fibrosis

Pulmonary fibrosis (PF) is an inevitable phase of many respiratory diseases with high mortality and limited effective treatments in the clinic. In PF, aberrant extracellular matrix (ECM) deposition is a significant pathological structural alteration that blocks intercellular crosstalk and hinders the deep penetration of therapeutics into lung tissues, reducing the effectiveness of conventional treatment strategies. Herein, a penetrating enhancer (Lipomicelles) composed of thermosensitive liposome shells loaded with collagenase IV and micellar cores containing thioketal bonds encapsulated with curcumin and decorated with cyclic RGDfc, is developed to alleviate PF. Specifically, Lipomicelles exhibit a cascade-responsive pattern to achieve precision delivery of curcumin through thermosensitivity, enhanced ECM penetration, site-specific targeting, and rapid release in injured alveolar epithelial type II cells (CellAEC2s). Subsequently, intercellular crosstalk is remodeled through the curcumin-mediated repair of CellAEC2s, combined with collagenase IV-mediated ECM degradation to inhibit myofibroblasts, ultimately achieving PF reversal. This work provides an innovative approach to enhance ECM penetration of therapeutics before remodeling intercellular crosstalk, addressing multi-phase PF therapy.

Radiomultiomics: quantitative CT clusters of severe asthma associated with multiomics

BACKGROUND

Lung quantitative computed tomography (qCT) severe asthma clusters have been reported, but their replication and underlying disease mechanisms are unknown. We identified and replicated qCT clusters of severe asthma in two independent asthma cohorts and determined their association with molecular pathways, using radiomultiomics, integrating qCT, multiomics and machine learning/artificial intelligence.

METHODS

We used consensus clustering on qCT measurements of airway and lung CT scans, performed in 105 severe asthmatic adults from the U-BIOPRED cohort. The same qCT measurements were used to replicate qCT clusters in a subsample of the ATLANTIS asthma cohort (n=97). We performed integrated enrichment analysis using blood, sputum, bronchial biopsies, bronchial brushings and nasal brushings transcriptomics and blood and sputum proteomics to characterise radiomultiomic-associated clusters (RACs).

RESULTS

qCT clusters and clinical features in U-BIOPRED were replicated in the matched ATLANTIS cohort. In the U-BIOPRED cohort, RAC1 (n=30) was predominantly female with elevated body mass index, mild airflow limitation, decreased CT lung volume and increased lung density and upregulation of the complement pathway. RAC2 (n=34) subjects had airway wall thickness and a mild degree of airflow limitation, with upregulation of proliferative pathways including neurotrophic receptor tyrosine kinase 2/tyrosine kinase receptor B, and downregulation of semaphorin pathways. RAC3 (n=41) showed increased lung attenuation area and air trapping, severe airflow limitation, hyperinflation, and upregulation of cytokine signalling and signalling by interleukin pathways, and matrix metallopeptidase 1, 2 and 9.

CONCLUSIONS

U-BIOPRED severe asthma qCT clusters were replicated in a matched independent asthmatic cohort and associated with specific molecular pathways. Radiomultiomics might represent a novel strategy to identify new molecular pathways in asthma pathobiology.

Lack of FMRP in the retina: Evidence of a retinal specific transcriptomic profile

Fragile X Syndrome (FXS), the most common inherited form of human intellectual disability, is a monogenic neurodevelopmental disorder caused by a loss-of-function mutation of the FMR1 gene. FMR1 is encoding the Fragile X Messenger Ribonucleo Protein (FMRP) an RNA-binding protein that regulates the translation of synaptic proteins. The absence of FMRP expression has many important consequences on synaptic plasticity and function, leading to the FXS clinical phenotype. Over the last decade, a visual neurosensorial phenotype had been described in the FXS patients as well as in the murine model (Fmr1-/ymice), characterized by retinal deficits associated to retinal perception alterations. However, although the transcriptomic profile in the absence of FMRP has been studied in the cerebral part of the central nervous system (CNS), there are no actual data for the retina which is an extension of the CNS. Herein, we investigate the transcriptomic profile of mRNA from whole retinas of Fmr1-/ymice. Interestingly, we found a specific signature of Fmrp absence on retinal mRNA expression with few common genes compared to other brain studies. Gene Ontology on these retinal specific genes demonstrated an enrichment in retinal development genes as well as in synaptic genes. These alterations could be linked to the reported retinal phenotype of the FXS condition. In conclusion, we describe for the first time, retinal-specific transcriptomic changes in the absence of FMRP.

The Current Molecular and Cellular Landscape of Chronic Obstructive Pulmonary Disease (COPD): A Review of Therapies and Efforts towards Personalized Treatment

Chronic obstructive pulmonary disease (COPD) ranks as the third leading cause of global illness and mortality. It is commonly triggered by exposure to respiratory irritants like cigarette smoke or biofuel pollutants. This multifaceted condition manifests through an array of symptoms and lung irregularities, characterized by chronic inflammation and reduced lung function. Present therapies primarily rely on maintenance medications to alleviate symptoms, but fall short in impeding disease advancement. COPD's diverse nature, influenced by various phenotypes, complicates diagnosis, necessitating precise molecular characterization. Omics-driven methodologies, including biomarker identification and therapeutic target exploration, offer a promising avenue for addressing COPD's complexity. This analysis underscores the critical necessity of improving molecular profiling to deepen our comprehension of COPD and identify potential therapeutic targets. Moreover, it advocates for tailoring treatment strategies to individual phenotypes. Through comprehensive exploration-based molecular characterization and the adoption of personalized methodologies, innovative treatments may emerge that are capable of altering the trajectory of COPD, instilling optimism for efficacious disease-modifying interventions.

Manipulating host secreted protein gene expression: an indirect approach by HPV11/16 E6/E7 to suppress PBMC cytokine secretion

Human papillomavirus (HPV) 11/16 E6/E7 proteins have been recognized to be pivotal in viral pathogenesis. This study sought to uncover the potential mechanisms of how HPV11/16 E6/E7-transfected keratinocytes inhibit cytokine secretion in peripheral blood mononuclear cells (PBMC). Upon co-culturing HPV11/16 E6/E7-transfected keratinocytes with PBMC in a non-contact manner, we observed a marked decrease in various cytokines secreted by PBMC. To determine if this suppression was mediated by specific common secreted factors, we conducted transcriptomic sequencing on these transfected cells. This analysis identified 53 common differentially secreted genes in all four HPV-transfected cells. Bioinformatics analysis demonstrated these genes were predominantly involved in immune regulation. Results from quantitative PCR (qPCR) and an extensive literature review suggested the downregulation of 12 genes (ACE2, BMP3, BPIFB1, CLU, CST6, CTF1, HMGB2, MMP12, PDGFA, RNASE7, SULF2, TGM2), and upregulation of 7 genes (CCL17, CCL22, FBLN1, PLAU, S100A7, S100A8, S100A9), may be crucial in modulating tumor immunity and combating pathogenic infections, with genes S100A8 and S100A9, and IL-17 signaling pathway being particularly noteworthy. Thus, HPV11/16 E6/E7 proteins may inhibit cytokine secretion of immune cells by altering the expression of host-secreted genes. Further exploration of these genes may yield new insights into the complex dynamics of HPV infection.

Understanding the Foreign Body Response via Single-Cell Meta-Analysis

Foreign body response (FBR) is a universal reaction to implanted biomaterial that can affect the function and longevity of the implant. A few studies have attempted to identify targets for treating FBR through the use of single-cell RNA sequencing (scRNA-seq), though the generalizability of these findings from an individual study may be limited. In our study, we perform a meta-analysis of scRNA-seq data from all available FBR mouse studies and integrate these data to identify gene signatures specific to FBR across different models and anatomic locations. We identify subclusters of fibroblasts and macrophages that emerge in response to foreign bodies and characterize their signaling pathways, gene ontology terms, and downstream mediators. The fibroblast subpopulations enriched in the setting of FBR demonstrated significant signaling interactions in the transforming growth factor-beta (TGF-β) signaling pathway, with known pro-fibrotic mediators identified as top expressed genes in these FBR-derived fibroblasts. In contrast, FBR-enriched macrophage subclusters highly expressed pro-fibrotic and pro-inflammatory mediators downstream of tumor necrosis factor (TNF) signaling. Cell-cell interactions were additionally interrogated using CellChat, with identification of key signaling interactions enriched between fibroblasts and macrophages in FBR. By combining multiple FBR datasets, our meta-analysis study identifies common cell-specific gene signatures enriched in foreign body reactions, providing potential therapeutic targets for patients requiring medical implants across a myriad of devices and indications.

Multi-Omics Characterization of Colon Mucosa and Submucosa/Wall from Crohn's Disease Patients

Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD) characterized by transmural disease. The concept of transmural healing (TH) has been proposed as an indicator of deep clinical remission of CD and as a predictor of favorable treatment endpoints. Understanding the pathophysiology involved in transmural disease is critical to achieving these endpoints. However, most studies have focused on the intestinal mucosa, overlooking the contribution of the intestinal wall in Crohn's disease. Multi-omics approaches have provided new avenues for exploring the pathogenesis of Crohn's disease and identifying potential biomarkers. We aimed to use transcriptomic and proteomic technologies to compare immune and mesenchymal cell profiles and pathways in the mucosal and submucosa/wall compartments to better understand chronic refractory disease elements to achieve transmural healing. The results revealed similarities and differences in gene and protein expression profiles, metabolic mechanisms, and immune and non-immune pathways between these two compartments. Additionally, the identification of protein isoforms highlights the complex molecular mechanisms underlying this disease, such as decreased RTN4 isoforms (RTN4B2 and RTN4C) in the submucosa/wall, which may be related to the dysregulation of enteric neural processes. These findings have the potential to inform the development of novel therapeutic strategies to achieve TH.

Ferroptosis and oxidative stress in endometriosis: A systematic review of the literature

BACKGROUND

Endometriosis (EMT) a common gynecological condition in women, an inflammatory disease characterized by the presence of endometrial tissue on organs and tissues in the pelvis, and is mainly associated with chronic pelvic pain and infertility. As the etiology has not been fully elucidated, current treatment is limited to surgery, hormones and painkillers, with more side effects and difficulty in achieving long-term relief. Oxidative stress manifests itself as an overproduction of reactive oxygen species, which has an integral impact in the pathology of female reproductive disorders. In this review, we evaluate the mechanisms of iron overload-induced oxidative stress and ferroptosis in EMT and their pathophysiological implications.

METHODS

Because the etiology has not been fully elucidated, current treatments are limited to surgery, hormones, and painkillers, which have many side effects and are difficult to achieve long-term relief.

RESULTS

We interpreted that antioxidants as well as ferroptosis inducers show promising results in the treatment of EMT, but their application in this population needs to be further investigated.

CONCLUSION

In combination with the interpretation of previous studies, it was shown that iron overload is present in the peritoneal fluid, endometriotic lesions, peritoneum and macrophages in the abdominal cavity. However, the programmed cellular ferroptosis associated with iron overload is resisted by endometriotic foci, which is critical to the pathophysiology of EMT with local iron overload and inflammation.

Anatomical and immunohistochemical analyses of the fusion of the premaxillary-maxillary suture in human fetuses

PURPOSE

The development of the premaxillary-maxillary suture (PMS) in human fetuses and a possible association between the fusion time of the PMS and maxillary deficiency were investigated. Expression of transforming growth factor beta (TGF-β1 and TGF-β3) and of fibulins (fibulin‑1 and fibulin-5) were also investigated.

METHODS

We analyzed 36 human fetus cadavers (19 males, 17 females; average age 23.97 ± 2.57 gestational weeks [gws], range 11-35 gws). Two cases, diagnosed with Down syndrome (DS), were characterized with maxillary deficiency; 34 fetus cadavers did not show any craniofacial abnormalities. The PMS was analyzed anatomically, followed by semi-quantitative immunohistochemical (IHC)-based expression analyses (i.e., TGF-β1/-β3, fibulin-1/-5). Spearman correlation test was conducted to investigate correlations.

RESULTS

In the fetuses without DS, the labial region of the PMS was open at 11 gws, after which it began to ossify from the middle to the upper and lower ends of the suture, typically fusing completely at 27 gws. Fetuses with DS demonstrated complete fusion of the labial region of PMS with a spongy bone structure at 23 gws and those without DS at 27 gws. IHC revealed similar patterns of TGF-βs and fibulins expression in the PMS during the human fetal period. There were significant positive correlations between the expression of TGF-β1 and TGF-β3 (r = 0.64, p = 0.009), TGF-β1 and fibulin‑1 (r = 0.66, p = 0.008), and TGF-β3 and fibulin‑1 (r = 0.67, p = 0.006).

CONCLUSION

Premature fusion of the PMS in the labial region during the human fetal period may be associated with maxillary deficiency, which is related to a class III malocclusion. Overall, the similar expression patterns of TGF-β1, TGF-β3 and fibulin‑1 suggested a close relationship between these factors in regulating the development of the PMS.

Exploring the novel duo of Reticulocalbin, and Sideroflexin as future biomarker candidates for Exacerbated Chronic Obstructive Pulmonary Disease

BACKGROUND

COPD is a complex respiratory disorder with high morbidity and mortality rates. Even with the current conventional diagnostic methods, including circulating inflammatory biomarkers, underdiagnosis rates in COPD remain as high as 70%. Our study was a comparative cross-sectional study that aimed to address the diagnostic challenges by identifying future biomarker candidates in COPD variants.

METHODS

This study used a label-free plasma proteomics approach that combined mass spectrometric data with bioinformatics to shed light on the functional roles of differentially expressed proteins in the COPD lung microenvironment. The predictive capacity of the screened proteins was assessed using Receiver Operating Characteristic (ROC) curves, with Western blot analysis validating protein expression patterns in an independent cohort.

RESULTS

Our study identified three DEPs-reticulocalbin-1, sideroflexin-4, and liprinα-3 that consistently exhibited altered expression in COPD exacerbation. ROC analysis indicated strong predictive potential, with AUC values of 0.908, 0.715, and 0.856 for RCN1, SFXN4, and LIPα-3, respectively. Validation through Western blot analysis confirmed their expression patterns in an independent validation cohort.

CONCLUSIONS

Our study discovered a novel duo of proteins reticulocalbin-1, and sideroflexin-4 that showed potential as valuable future biomarkers for the diagnosis and clinical management of COPD exacerbations.

Airway wall extracellular matrix changes induced by bronchial thermoplasty in severe asthma

BACKGROUND

Airway remodeling is a prominent feature of asthma, which involves increased airway smooth muscle mass and altered extracellular matrix composition. Bronchial thermoplasty (BT), a bronchoscopic treatment for severe asthma, targets airway remodeling.

OBJECTIVE

We sought to investigate the effect of BT on extracellular matrix composition and its association with clinical outcomes.

METHODS

This is a substudy of the TASMA trial. Thirty patients with severe asthma were BT-treated, of whom 13 patients were treated for 6 months with standard therapy (control group) before BT. Demographic data, clinical data including pulmonary function, and bronchial biopsies were collected. Biopsies at BT-treated and nontreated locations were analyzed by histological and immunohistochemical staining. Associations between histology and clinical outcomes were explored.

RESULTS

Six months after treatment, it was found that the reticular basement membrane thickness was reduced from 7.28 μm to 5.74 μm (21% relative reduction) and the percentage area of tissue positive for collagen increased from 26.3% to 29.8% (13% relative increase). Collagen structure analysis revealed a reduction in the curvature frequency of fibers. The percentage area positive for fibulin-1 and fibronectin increased by 2.5% and 5.9%, respectively (relative increase of 124% and 15%). No changes were found for elastin. The changes in collagen and fibulin-1 negatively associated with changes in FEV1 reversibility.

CONCLUSIONS

Besides reduction of airway smooth muscle mass, BT has an impact on reticular basement membrane thickness and the extracellular matrix arrangement characterized by an increase in tissue area occupied by collagen with a less dense fiber organization. Both collagen and fibulin-1 are negatively associated with the change in FEV1 reversibility.

Identification and targeting of cancer-associated fibroblast signature genes for prognosis and therapy in Cutaneous melanoma

BACKGROUND

Cancer-associated fibroblasts (CAFs) play pivotal roles in tumor invasion and metastasis. However, studies on CAF biomarkers in Cutaneous Melanoma (CM) are still scarce. This study aimed to explore the potential CAF biomarkers in CM, propose the potential therapeutic targets, and provide new insights for targeted therapy of CAFs in CM.

METHODS

We utilized weighted gene co-expression network analysis to identify CAF signature genes in CM, and conducted comprehensive bioinformatics analysis on the CAF risk score established by these genes. Moreover, single-cell sequencing analysis, spatial transcriptome analysis, and cell experiments were utilized for verifying the expression and distribution pattern of signature genes. Furthermore, molecular docking was employed to screen potential target drugs.

RESULTS

FBLN1 and COL5A1, two crucial CAF signature genes, were screened to establish the CAF risk score. Subsequently, a comprehensive bioinformatic analysis of the CAF risk score revealed that high-risk score group was significantly enriched in pathways associated with tumor progression. Besides, CAF risk score was significantly negatively correlated with clinical prognosis, immunotherapy response, and tumor mutational burden in CM patients. In addition, FBLN1 and COL5A1 were further identified as CAF-specific biomarkers in CM by multi-omics analysis and experimental validation. Eventually, based on these two targets, Mifepristone and Dexamethasone were screened as potential anti-CAFs drugs.

CONCLUSION

The findings indicated that FBLN1 and COL5A1 were the CAF signature genes in CM, which were associated with the progression, treatment, and prognosis of CM. The comprehensive exploration of CAF signature genes is expected to provide new insight for clinical CM therapy.

TLR7 promotes smoke-induced experimental lung damage through the activity of mast cell tryptase

Toll-like receptor 7 (TLR7) is known for eliciting immunity against single-stranded RNA viruses, and is increased in both human and cigarette smoke (CS)-induced, experimental chronic obstructive pulmonary disease (COPD). Here we show that the severity of CS-induced emphysema and COPD is reduced in TLR7-deficient mice, while inhalation of imiquimod, a TLR7-agonist, induces emphysema without CS exposure. This imiquimod-induced emphysema is reduced in mice deficient in mast cell protease-6, or when wild-type mice are treated with the mast cell stabilizer, cromolyn. Furthermore, therapeutic treatment with anti-TLR7 monoclonal antibody suppresses CS-induced emphysema, experimental COPD and accumulation of pulmonary mast cells in mice. Lastly, TLR7 mRNA is increased in pre-existing datasets from patients with COPD, while TLR7+ mast cells are increased in COPD lungs and associated with severity of COPD. Our results thus support roles for TLR7 in mediating emphysema and COPD through mast cell activity, and may implicate TLR7 as a potential therapeutic target.

Integrated single-cell and spatial transcriptomics reveals heterogeneity of fibroblast and pivotal genes in psoriasis

Psoriasis, which is one of the most common skin diseases, involves an array of complex immune constituents including T cells, dendritic cells and monocytes. Particularly, the cytokine IL17A, primarily generated by TH17 cells, assumes a crucial function in the etiology of psoriasis. In this study, a comprehensive investigation utilizing bulk RNA analysis, single-cell RNA sequencing, and spatial transcriptomics was employed to elucidate the underlying mechanisms of psoriasis. Our study revealed that there is an overlap between the genes that are differentially expressed in psoriasis patients receiving three anti-IL17A monoclonal antibody drugs and the genes that are differentially expressed in lesion versus non-lesion samples in these patients. Further analysis using single-cell and spatial data from psoriasis samples confirmed the expression of hub genes that had low expressions in psoriasis tissue but were up-regulated after anti-IL17A treatments. These genes were found to be associated with the treatment effects of brodalumab and methotrexate, but not adalimumab, etanercept, and ustekinumab. Additionally, these genes were predominantly expressed in fibroblasts. In our study, fibroblasts were categorized into five clusters. Notably, hub genes exhibited predominant expression in cluster 3 fibroblasts, which were primarily engaged in the regulation of the extracellular matrix and were predominantly located in the reticular dermis. Subsequent analysis unveiled that cluster 3 fibroblasts also established communication with epithelial cells and monocytes via the ANGPTL-SDC4 ligand-receptor configuration, and their regulation was governed by the transcription factor TWIST1. Conversely, cluster 4 fibroblasts, responsible for vascular endothelial regulation, were predominantly distributed in the papillary dermis. Cluster 4 predominantly engaged in interactions with endothelial cells via MDK signals and was governed by the distinctive transcription factor, ERG. By means of an integrated analysis encompassing bulk transcriptomics, single-cell RNA sequencing, and spatial transcriptomics, we have discerned genes and clusters of fibroblasts that potentially contribute to the pathogenesis of psoriasis.

Advanced models for respiratory disease and drug studies

The global burden of respiratory diseases is enormous, with many millions of people suffering and dying prematurely every year. The global COVID-19 pandemic witnessed recently, along with increased air pollution and wildfire events, increases the urgency of identifying the most effective therapeutic measures to combat these diseases even further. Despite increasing expenditure and extensive collaborative efforts to identify and develop the most effective and safe treatments, the failure rates of drugs evaluated in human clinical trials are high. To reverse these trends and minimize the cost of drug development, ineffective drug candidates must be eliminated as early as possible by employing new, efficient, and accurate preclinical screening approaches. Animal models have been the mainstay of pulmonary research as they recapitulate the complex physiological processes, Multiorgan interplay, disease phenotypes of disease, and the pharmacokinetic behavior of drugs. Recently, the use of advanced culture technologies such as organoids and lung-on-a-chip models has gained increasing attention because of their potential to reproduce human diseased states and physiology, with clinically relevant responses to drugs and toxins. This review provides an overview of different animal models for studying respiratory diseases and evaluating drugs. We also highlight recent progress in cell culture technologies to advance integrated models and discuss current challenges and present future perspectives.

Inflammatory and antiviral responses to influenza A virus infection are dysregulated in pregnant mice with allergic airway disease

Influenza A virus (IAV) infections are increased during pregnancy especially with asthma as a comorbidity, leading to asthma exacerbations, secondary bacterial infections, intensive care unit admissions, and mortality. We aimed to define the processes involved in increased susceptibility and severity of IAV infections during pregnancy, especially with asthma. We sensitized mice to house dust mite (HDM), induced pregnancy, and challenged with HDM to induce allergic airway disease (AAD). At midpregnancy, we induced IAV infection. We assessed viral titers, airway inflammation, lung antiviral responses, mucus hypersecretion, and airway hyperresponsiveness (AHR). During early IAV infection, pregnant mice with AAD had increased mRNA expression of the inflammatory markers Il13 and IL17 and reduced mRNA expression of the neutrophil chemoattractant marker Kc. These mice had increased mucous hyperplasia and increased AHR. miR155, miR574, miR223, and miR1187 were also reduced during early infection, as was mRNA expression of the antiviral β-defensins, Bd1, Bd2, and Spd and IFNs, Ifnα, Ifnβ, and Ifnλ. During late infection, Il17 was still increased as was eosinophil infiltration in the lungs. mRNA expression of Kc was reduced, as was neutrophil infiltration and mRNA expression of the antiviral markers Ifnβ, Ifnλ, and Ifnγ and Ip10, Tlr3, Tlr9, Pkr, and Mx1. Mucous hyperplasia was still significantly increased as was AHR. Early phase IAV infection in pregnancy with asthma heightens underlying inflammatory asthmatic phenotype and reduces antiviral responses.NEW & NOTEWORTHY Influenza A virus (IAV) infection during pregnancy with asthma is a major health concern leading to increased morbidity for both mother and baby. Using murine models, we show that IAV infection in pregnancy with allergic airway disease is associated with impaired global antiviral and antimicrobial responses, increased lung inflammation, mucus hypersecretion, and airway hyperresponsiveness (AHR). Targeting specific β-defensins or microRNAs (miRNAs) may prove useful in future treatments for IAV infection during pregnancy.

Systemic alterations in neutrophils and their precursors in early-stage chronic obstructive pulmonary disease

Systemic inflammation is established as part of late-stage severe lung disease, but molecular, functional, and phenotypic changes in peripheral immune cells in early disease stages remain ill defined. Chronic obstructive pulmonary disease (COPD) is a major respiratory disease characterized by small-airway inflammation, emphysema, and severe breathing difficulties. Using single-cell analyses we demonstrate that blood neutrophils are already increased in early-stage COPD, and changes in molecular and functional neutrophil states correlate with lung function decline. Assessing neutrophils and their bone marrow precursors in a murine cigarette smoke exposure model identified similar molecular changes in blood neutrophils and precursor populations that also occur in the blood and lung. Our study shows that systemic molecular alterations in neutrophils and their precursors are part of early-stage COPD, a finding to be further explored for potential therapeutic targets and biomarkers for early diagnosis and patient stratification.

Research advances in endometriosis-related signaling pathways: A review

Endometriosis (EM) is characterized by the existence of endometrial mucosa outside the uterine cavity, which causesinfertility, persistent aches, and a decline in women's quality of life. Both hormone therapies and nonhormone therapies, such as NSAIDs, are ineffective, generic categories of EM drugs. Endometriosis is a benign gynecological condition, yet it shares a number of features with cancer cells, including immune evasion, survival, adhesion, invasion, and angiogenesis. Several endometriosis-related signaling pathways are comprehensively reviewed in this article, including E2, NF-κB, MAPK, ERK, PI3K/Akt/mTOR, YAP, Wnt/β-catenin, Rho/ROCK, TGF-β, VEGF, NO, iron, cytokines and chemokines. To find and develop novel medications for the treatment of EM, it is essential to implicitly determine the molecular pathways that are disordered during EM development. Additionally, research on the shared pathways between EM and tumors can provide hypotheses or suggestions for endometriosis therapeutic targets.

Single-Cell Profiling Uncovers the Roles of Endometrial Fibrosis and Microenvironmental Changes in Adenomyosis

Purpose

Adenomyosis (AM) is a common benign uterine disorder that has deleterious effects on women's health. However, the pathogenesis of AM is not clearly understood. We aimed to investigate the pathophysiological changes and molecular mechanism in AM.

Methods

Single-cell RNA sequencing (scRNA-seq) was employed to construct a transcriptomic atlas of various cell subsets from the ectopic endometrium (EC) and eutopic endometrium (EM) of one AM patient and evaluate differential expression. The Cell Ranger software pipeline (version 4.0.0) was applied to conduct sample demultiplexing, barcode processing and mapping reads to the reference genome (human GRCh38). Different cell types were classified with markers with the "FindAllMarkers" function, and differential gene expression analysis was performed with Seurat software in R. The findings were confirmed by Reverse Transcription Real-Time PCR using samples from three AM patients.

Results

We identified nine cell types: endothelial cells, epithelial cells, myoepithelial cells, smooth muscle cells, fibroblasts, lymphocytes, mast cells, macrophages and unknown cells. A number of differentially expressed genes, including CLO4A1, MMP1, TPM2 and CXCL8, were identified from all cell types. Functional enrichment showed that aberrant gene expression in fibroblasts and immune cells was related to fibrosis-associated terms, such as extracellular matrix dysregulation, focal adhesion and the PI3K-Akt signaling pathway. We also identified fibroblast subtypes and determined a potential developmental trajectory related to AM. In addition, we identified increased cell-cell communication patterns in EC, highlighting the imbalanced microenvironment in AM progression.

Conclusion

Our results support the theory of endometrial-myometrial interface disruption for AM, and repeated tissue injury and repair could lead to increased fibrosis in the endometrium. Therefore, the present study reveals the association between fibrosis, the microenvironment, and AM pathogenesis. This study provides insight into the molecular mechanisms regulating AM progression.

Antiviral Responses of Tissue-resident CD49a+ Lung Natural Killer Cells Are Dysregulated in Chronic Obstructive Pulmonary Disease

Rationale: Tissue-resident natural killer (trNK) cells have been identified in numerous organs, but little is known about their functional contribution to respiratory immunity, in particular during chronic lung diseases such as chronic obstructive pulmonary disease (COPD). Objectives: To investigate the phenotype and antiviral responses of trNK cells in murine cigarette smoke-induced experimental COPD and in human lung parenchyma from COPD donors. Methods: Mice were exposed to cigarette smoke for 12 weeks to induce COPD-like lung disease. Lung trNK cell phenotypes and function were analyzed by flow cytometry in both murine and human disease with and without challenge with influenza A virus. Measurements and Main Results: In the mouse lung, CD49a+CD49b+EOMES+ and CD49a+CD49b-EOMESlo NK cell populations had a distinct phenotype compared with CD49a- circulating NK cells. CD49a+ NK cells were more extensively altered earlier in disease onset than circulating NK cells, and increased proportions of CD49a+ NK cells correlated with worsening disease in both murine and human COPD. Furthermore, the presence of lung disease delayed both circulating and trNK cell functional responses to influenza infection. CD49a+ NK cells markedly increased their NKG2D, CD103, and CD69 expression in experimental COPD after influenza infection, and human CD49a+ NK cells were hyperactive to ex vivo influenza infection in COPD donors. Conclusions: Collectively, these results demonstrate that trNK cell function is altered in cigarette smoke-induced disease and suggests that smoke exposure may aberrantly prime trNK cell responsiveness to viral infection. This may contribute to excess inflammation during viral exacerbations of COPD.

Mechanisms of Immune-Related Long Non-Coding RNAs in Spleens of Mice Vaccinated with 23-Valent Pneumococcal Polysaccharide Vaccine (PPV23)

The 23-valent pneumococcal vaccine (PPV23) is a classical common vaccine used to prevent pneumococcal disease. In past decades, it was thought that vaccination with this vaccine induces humoral immunity, thereby reducing the disease associated with infection with 23 common serotypes of Streptococcus pneumoniae (Sp). However, for this polysaccharide vaccine, the mechanism of immune response at the transcriptional level has not been fully studied. To identify the lncRNAs (long noncoding RNAs) and mRNAs in spleens related to immunity after PPV23 vaccination in mice, high-throughput RNA sequencing of spleens between a PPV23 treatment group and a control group were performed and evaluated in this study. The RNA-seq results identified a total of 41,321 mRNAs and 34,375 lncRNAs, including 55 significantly differentially expressed (DE) mRNAs and 389 DE lncRNAs (p < 0.05) between the two groups. GO and KEGG annotation analysis indicated that the target genes of DE lncRNAs and DE mRNAs were related to T-cell costimulation, positive regulation of alpha–beta T-cell differentiation, the CD86 biosynthetic process, and the PI3K-Akt signaling pathway, indicating that the polysaccharide component antigens of PPV23 might activate a cellular immune response during the PPV23 immunization process. Moreover, we found that Trim35 (tripartite motif containing 35), a target gene of lncRNA MSTRG.9127, was involved in regulating immunity. Our study provides a catalog of lncRNAs and mRNAs associated with immune cells’ proliferation and differentiation, and they deserve further study to deepen the understanding of the biological processes in the regulation of PPV23 during humoral immunity and cellular immunity.

Dual viscosity mixture vehicle for intratympanic steroid treatment modifies the ROS and inflammation related proteomes

Until recently, the most standard treatment for sensorineural or sudden hearing loss, which is caused by inner ear damage or deterioration, has been systemic oral steroid administration. In recent, intratympanic steroid injections such as dexamethasone have been used for the treatment of sudden hearing loss as well. It is injected into the tympanic cavity through its membrane and is expected to diffuse over the round window located between the tympanic cavity and the inner ear. However, in clinical situations, the delivery time of steroids to the inner ear is shorter than 24 h, which does not allow for a sufficient therapeutic effect. Therefore, we applied a previously invented dual viscosity mixture vehicle (DVV) for intratympanic dexamethasone to a guinea pig model, which could reduce the side effects of systemic steroid administration with sufficient dwelling time for the treatment of hearing loss, and we investigated the physiological changes with a global proteomic approach. In this study, we extracted perilymph in three different conditions from guinea pigs treated with dexamethasone-embedded DVV, dexamethasone mixed in saline, and control groups to compare proteomic changes using tandem mass spectrometry analysis. After liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) analysis, we first identified 46 differentially expressed proteins (DEPs) that were statistically significant after one-way ANOVA multiple-sample test. We also performed pairwise comparisons among each group to identify DEPs closely related to the treatment response of dexamethasone-embedded DVV. Gene ontology enrichment analysis showed that these DEPs were mostly related to inflammation, immune, actin remodeling, and antioxidant-related processes. As a result, the proteome changes in the DVV-treated groups revealed that most upregulated proteins activate the cell proliferation process, and downregulated proteins inhibit apoptosis and inflammatory reactions. Moreover, the reactive oxygen process was also regulated by DEPs after DVV treatment.

Airway and parenchyma transcriptomics in a house dust mite model of experimental asthma

Lung transcriptomics studies in asthma have provided valuable information in the whole lung context, however, deciphering the individual contributions of the airway and parenchyma in disease pathogenesis may expedite the development of novel targeted treatment strategies. In this study, we performed transcriptomics on the airway and parenchyma using a house dust mite (HDM)-induced model of experimental asthma that replicates key features of the human disease. HDM exposure increased the expression of 3,255 genes, of which 212 were uniquely increased in the airways, 856 uniquely increased in the parenchyma, and 2187 commonly increased in both compartments. Further interrogation of these genes using a combination of network and transcription factor enrichment analyses identified several transcription factors that regulate airway and/or parenchymal gene expression, including transcription factor EC (TFEC), transcription factor PU.1 (SPI1), H2.0-like homeobox (HLX), metal response element binding transcription factor-1 (MTF1) and E74-like factor 4 (ets domain transcription factor, ELF4) involved in controlling innate immune responses. We next assessed the effects of inhibiting lung SPI1 responses using commercially available DB1976 and DB2313 on key disease outcomes. We found that both compounds had no protective effects on airway inflammation, however DB2313 (8 mg/kg) decreased mucus secreting cell number, and both DB2313 (1 mg/kg) and DB1976 (2.5 mg/kg and 1 mg/kg) reduced small airway collagen deposition. Significantly, both compounds decreased airway hyperresponsiveness. This study demonstrates that SPI1 is important in HDM-induced experimental asthma and that its pharmacological inhibition reduces HDM-induced airway collagen deposition and hyperresponsiveness.

Probiotic Bifidobacterium longum subsp. longum Protects against Cigarette Smoke-Induced Inflammation in Mice

Bifidobacterium are prominent gut commensals that produce the short-chain fatty acid (SCFA) acetate, and they are often used as probiotics. Connections between the gut and the lung, termed the gut-lung axis, are regulated by the microbiome. The gut-lung axis is increasingly implicated in cigarette smoke-induced diseases, and cigarette smoke exposure has been associated with depletion of Bifidobacterium species. In this study, we assessed the impact of acetate-producing Bifidobacterium longum subsp. longum (WT) and a mutant strain with an impaired acetate production capacity (MUT) on cigarette smoke-induced inflammation. The mice were treated with WT or MUT B. longum subsp. longum and exposed to cigarette smoke for 8 weeks before assessments of lung inflammation, lung tissue gene expression and cecal SCFAs were performed. Both strains of B. longum subsp. longum reduced lung inflammation, inflammatory cytokine expression and adhesion factor expression and alleviated cigarette smoke-induced depletion in caecum butyrate. Thus, the probiotic administration of B. longum subsp. longum, irrespective of its acetate-producing capacity, alleviated cigarette smoke-induced inflammation and the depletion of cecal butyrate levels.

Adverse roles of mast cell chymase-1 in COPD

BACKGROUND

COPD is the third leading cause of death worldwide. Cigarette smoke (CS)-induced chronic inflammation inducing airway remodelling, emphysema and impaired lung function is the primary cause. Effective therapies are urgently needed. Human chymase (hCMA)1 and its orthologue mCMA1/mouse mast cell protease (mMCP)5 are exocytosed from activated mast cells and have adverse roles in numerous disorders, but their role in COPD is unknown.

METHODS

We evaluated hCMA1 levels in lung tissues of COPD patients. We used mmcp5-deficient (-/-) mice to evaluate this protease's role and potential for therapeutic targeting in CS-induced experimental COPD. In addition, we used ex vivo/in vitro studies to define mechanisms.

RESULTS

The levels of hCMA1 mRNA and CMA1+ mast cells were increased in lung tissues from severe compared to early/mild COPD patients, non-COPD smokers and healthy controls. Degranulated mast cell numbers and mMCP5 protein were increased in lung tissues of wild-type mice with experimental COPD. mmcp5 -/- mice were protected against CS-induced inflammation and macrophage accumulation, airway remodelling, emphysema and impaired lung function in experimental COPD. CS extract challenge of co-cultures of mast cells from wild-type, but not mmcp5 -/- mice with wild-type lung macrophages increased in tumour necrosis factor (TNF)-α release. It also caused the release of CMA1 from human mast cells, and recombinant hCMA-1 induced TNF-α release from human macrophages. Treatment with CMA1 inhibitor potently suppressed these hallmark features of experimental COPD.

CONCLUSION

CMA1/mMCP5 promotes the pathogenesis of COPD, in part, by inducing TNF-α expression and release from lung macrophages. Inhibiting hCMA1 may be a novel treatment for COPD.

Matricellular proteins in cutaneous wound healing

Cutaneous wound healing is a complex process that encompasses alterations in all aspects of the skin including the extracellular matrix (ECM). ECM consist of large structural proteins such as collagens and elastin as well as smaller proteins with mainly regulative properties called matricellular proteins. Matricellular proteins bind to structural proteins and their functions include but are not limited to interaction with cell surface receptors, cytokines, or protease and evoking a cellular response. The signaling initiated by matricellular proteins modulates differentiation and proliferation of cells having an impact on the tissue regeneration. In this review we give an overview of the matricellular proteins that have been found to be involved in cutaneous wound healing and summarize the information known to date about their functions in this process.

Understanding the pathogenesis of occupational coal and silica dust-associated lung disease

Workers in the mining and construction industries are at increased risk of respiratory and other diseases as a result of being exposed to harmful levels of airborne particulate matter (PM) for extended periods of time. While clear links have been established between PM exposure and the development of occupational lung disease, the mechanisms are still poorly understood. A greater understanding of how exposures to different levels and types of PM encountered in mining and construction workplaces affect pathophysiological processes in the airways and lungs and result in different forms of occupational lung disease is urgently required. Such information is needed to inform safe exposure limits and monitoring guidelines for different types of PM and development of biomarkers for earlier disease diagnosis. Suspended particles with a 50% cut-off aerodynamic diameter of 10 µm and 2.5 µm are considered biologically active owing to their ability to bypass the upper respiratory tract's defences and penetrate deep into the lung parenchyma, where they induce potentially irreversible damage, impair lung function and reduce the quality of life. Here we review the current understanding of occupational respiratory diseases, including coal worker pneumoconiosis and silicosis, and how PM exposure may affect pathophysiological responses in the airways and lungs. We also highlight the use of experimental models for better understanding these mechanisms of pathogenesis. We outline the urgency for revised dust control strategies, and the need for evidence-based identification of safe level exposures using clinical and experimental studies to better protect workers' health.

Defining the versican interactome in lung health and disease

The extracellular matrix (ECM) imparts critical mechanical and biochemical information to cells in the lungs. Proteoglycans are essential constituents of the ECM and play a crucial role in controlling numerous biological processes, including regulating cellular phenotype and function. Versican, a chondroitin sulfate proteoglycan required for embryonic development, is almost absent from mature, healthy lungs and is reexpressed and accumulates in acute and chronic lung disease. Studies using genetically engineered mice show that the versican-enriched matrix can be pro- or anti-inflammatory depending on the cellular source or disease process studied. The mechanisms whereby versican develops a contextual ECM remain largely unknown. The primary goal of this review is to provide an overview of the interaction of versican with its many binding partners, the "versican interactome," and how through these interactions, versican is an integrator of complex extracellular information. Hopefully, the information provided in this review will be used to develop future studies to determine how versican and its binding partners can develop contextual ECMs that control select biological processes. Although this review focuses on versican and the lungs, what is described can be extended to other proteoglycans, tissues, and organs.

Airway and parenchymal transcriptomics in a novel model of asthma and COPD overlap

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are common chronic respiratory diseases, and some patients have overlapping disease features, termed asthma-COPD overlap (ACO). Patients characterized with ACO have increased disease severity; however, the mechanisms driving this have not been widely studied.

OBJECTIVES

This study sought to characterize the phenotypic and transcriptomic features of experimental ACO in mice induced by chronic house dust mite antigen and cigarette smoke exposure.

METHODS

Female BALB/c mice were chronically exposed to house dust mite antigen for 11 weeks to induce experimental asthma, cigarette smoke for 8 weeks to induce experimental COPD, or both concurrently to induce experimental ACO. Lung inflammation, structural changes, and lung function were assessed. RNA-sequencing was performed on separated airway and parenchyma lung tissues to assess transcriptional changes. Validation of a novel upstream driver SPI1 in experimental ACO was assessed using the pharmacological SPI1 inhibitor, DB2313.

RESULTS

Experimental ACO recapitulated features of both asthma and COPD, with mixed pulmonary eosinophilic/neutrophilic inflammation, small airway collagen deposition, and increased airway hyperresponsiveness. Transcriptomic analysis identified common and distinct dysregulated gene clusters in airway and parenchyma samples in experimental asthma, COPD, and ACO. Upstream driver analysis revealed increased expression of the transcription factor Spi1. Pharmacological inhibition of SPI1 using DB2313, reduced airway remodeling and airway hyperresponsiveness in experimental ACO.

CONCLUSIONS

A new experimental model of ACO featuring chronic dual exposures to house dust mite and cigarette smoke mimics key disease features observed in patients with ACO and revealed novel disease mechanisms, including upregulation of SPI1, that are amenable to therapy.

Aim2 suppresses cigarette smoke-induced neutrophil recruitment, neutrophil caspase-1 activation and anti-Ly6G-mediated neutrophil depletion

Increased inflammasome responses are strongly implicated in inflammatory diseases; however, their specific roles are incompletely understood. Therefore, we sought to examine the roles of nucleotide‐binding oligomerization domain–like receptor (NLR) family, pyrin domain–containing 3 (NLRP3) and absent in melanoma‐2 (AIM2) inflammasomes in cigarette smoke–induced inflammation in a model of experimental chronic obstructive pulmonary disease (COPD). We targeted NLRP3 with the inhibitor MCC950 given prophylactically or therapeutically and examined Aim2^−/− mice in cigarette smoke–induced experimental COPD. MCC950 treatment had minimal effects on disease development and/or progression. Aim2^−/− mice had increased airway neutrophils with decreased caspase‐1 levels, independent of changes in lung neutrophil chemokines. Suppressing neutrophils with anti‐Ly6G in experimental COPD in wild‐type mice reduced neutrophils in bone marrow, blood and lung. By contrast, anti‐Ly6G treatment in Aim2^−/− mice with experimental COPD had no effect on neutrophils in bone marrow, partially reduced neutrophils in the blood and had no effect on neutrophils or neutrophil caspase‐1 levels in the lungs. These findings identify that following cigarette smoke exposure, Aim2 is important for anti‐Ly6G–mediated depletion of neutrophils, suppression of neutrophil recruitment and mediates activation of caspase‐1 in neutrophils.

Chronic lung diseases: entangled in extracellular matrix

The extracellular matrix (ECM) is the scaffold that provides structure and support to all organs, including the lung; however, it is also much more than this. The ECM provides biochemical and biomechanical cues to cells that reside or transit through this micro-environment, instructing their responses. The ECM structure and composition changes in chronic lung diseases; how such changes impact disease pathogenesis is not as well understood. Cells bind to the ECM through surface receptors, of which the integrin family is one of the most widely recognised. The signals that cells receive from the ECM regulate their attachment, proliferation, differentiation, inflammatory secretory profile and survival. There is extensive evidence documenting changes in the composition and amount of ECM in diseased lung tissues. However, changes in the topographical arrangement, organisation of the structural fibres and stiffness (or viscoelasticity) of the matrix in which cells are embedded have an undervalued but strong impact on cell phenotype. The ECM in diseased lungs also changes in physical and biomechanical ways that drive cellular responses. The characteristics of these environments alter cell behaviour and potentially orchestrate perpetuation of lung diseases. Future therapies should target ECM remodelling as much as the underlying culprit cells.

Nanoparticle Delivery Platforms for RNAi Therapeutics Targeting COVID-19 Disease in the Respiratory Tract

Since December 2019, a pandemic of COVID-19 disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread across the globe. At present, the Food and Drug Administration (FDA) has issued emergency approval for the use of some antiviral drugs. However, these drugs still have limitations in the specific treatment of COVID-19, and as such, new treatment strategies urgently need to be developed. RNA-interference-based gene therapy provides a tractable target for antiviral treatment. Ensuring cell-specific targeted delivery is important to the success of gene therapy. The use of nanoparticles (NPs) as carriers for the delivery of small interfering RNA (siRNAs) to specific tissues or organs of the human body could play a crucial role in the specific therapy of severe respiratory infections, such as COVID-19. In this review, we describe a variety of novel nanocarriers, such as lipid NPs, star polymer NPs, and glycogen NPs, and summarize the pre-clinical/clinical progress of these nanoparticle platforms in siRNA delivery. We also discuss the application of various NP-capsulated siRNA as therapeutics for SARS-CoV-2 infection, the challenges with targeting these therapeutics to local delivery in the lung, and various inhalation devices used for therapeutic administration. We also discuss currently available animal models that are used for preclinical assessment of RNA-interference-based gene therapy. Advances in this field have the potential for antiviral treatments of COVID-19 disease and could be adapted to treat a range of respiratory diseases.

Upregulated Fibulin-1 Increased Endometrial Stromal Cell Viability and Migration by Repressing EFEMP1-Dependent Ferroptosis in Endometriosis

Endometriosis (EMS) is a prevalent disease in women characterized by the presence of endometrial stroma and glands outside the uterus. Recent studies have showed that EMS is correlated with the resistance of endometrial stromal cells (ESCs) to ferroptosis, an iron-dependent nonapoptotic cell death. Fibulin-1 (FBLN1) is a newly identified target regulated by progesterone in the process of ESC decidualization. However, the role of FBLN1 in regulating ESC ferroptosis and EMS remains unclear. In the present study, the gene expression profiles of GSE58178, GSE23339, and GSE25628 were downloaded from the Gene Expression Omnibus (GEO) database, and the commonly differential genes were identified using Venn diagram analysis. The role of FBLN1 in ESC viability and migration was evaluated using Cell Counting Kit-8, transwell, and western blot analysis. We found that the FBLN1 expression was increased significantly in eutopic and ectopic endometrial tissues of patients with EMS compared with normal endometrium. FBLN1 overexpression in normal ESCs (NESCs) promoted cell viability and migration, whereas FBLN1 inhibition in ectopic ESCs (EESCs) decreased cell viability and migration. Furthermore, FBLN1 inhibition facilitated EESC death by triggering ferroptosis, as evidenced by increased Fe2+, lipid ROS, and malondialdehyde (MDA) level and decreased glutathione peroxidase 4 (GPX4) expression and glutathione (GSH) level. Mechanistically, FBLN1 interacted with EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1) and increased the protein stability of EFEMP1. More importantly, EFEMP1 silencing repressed the effect of FBLN1 on regulating EESC ferroptosis, death, and migration. Taken together, these results verify the role of the FBLN1/EFEMP1/ferroptosis pathway in the pathogenesis of EMS, and silencing of FBLN1/EFEMP1 might be an effective approach to treat EMS.

FBLN1 promotes chondrocyte proliferation by increasing phosphorylation of Smad2

BACKGROUND

The role of fibulin-1 or FBLN1 in chondrocyte proliferation has not been reported so far. In this study, we aimed to verify whether FBLN1 promotes chondrocyte proliferation in elderly patients with knee osteoarthritis by phosphorylating Smad2.

METHODS

Chondrocytes were isolated from cartilage samples collected from elderly patients with osteoarthritis (n = 6) and young patients (n = 6). The isolated chondrocytes were divided into the following three groups: control (medium only); cells transfected with adenovirus expressing green fluorescent protein (Ad-GFP); and those transfected with adenovirus expressing green fluorescent protein and FBLN1 (Ad-GFP-FBLN1). Furthermore, chondrocytes were divided into the following three groups in the mechanistic analysis: group 1, medium only; group 2, Ad-FBLN1; and group 3, Ad-FBLN1+pSmad2 inhibitor. The cells were analyzed for the relevant indicators after culturing for 48 h.

RESULTS

There were more EdU-positive cells in the Ad-GFP-FBLN1 group than in the other two groups (both P < 0.05). Compared with the other two groups, the level of pSmad2 and Col2 in the Ad-GFP-FBLN1 group was significantly increased (P < 0.05). The gene expression level of each indicator was consistent with the protein expression level. There was no significant difference in the indicators between groups 1 and 3. The percentage of EdU-positive cells in group 2 was higher than that in the other two groups (P < 0.05). The expression of pSmad2 and Col2 in group 2 was higher than that in the other two groups (both P < 0.05).

CONCLUSION

FBLN1 can promote chondrocyte proliferation in the knee cartilage in elderly patients by phosphorylating Smad2.

Loss of Hyaluronan and Proteoglycan Link Protein-1 Induces Tumorigenesis in Colorectal Cancer

Colorectal cancer (CRC) is the third most common diagnosed cancer worldwide, but there are no effective cures for it. Hyaluronan and proteoglycan link protein-1 (HAPLN1) is a component of the extracellular matrix (ECM) proteins and involved in the tumor environment in the colon. Transforming growth factor (TGF)-β is a key cytokine that regulates the deposition of ECM proteins in CRC. However, the role of HAPLN1 in TGF-β contributions to CRC remains unknown. We found that the mRNA expression of HAPLN1 was decreased in tumors from CRC patients compared with healthy controls and normal tissue adjacent to the tumor using two existing microarray datasets. This was validated at the protein level by tissue array from CRC patients (n = 59). HAPLN1 protein levels were also reduced in human CRC epithelial cells after 24 h of TGF-β stimulation, and its protein expression correlated with type I collagen alpha-1 (COL1A1) in CRC. Transfection of HAPLN1 overexpression plasmids into these cells increased protein levels but reduced COL1A1 protein, tumor growth, and cancer cell migration. TGF-β stimulation increased Smad2/3, p-Smad2/3, Smad4, and E-adhesion proteins; however, HAPLN1 overexpression restored these proteins to baseline levels in CRC epithelial cells after TGF-β stimulation. These findings suggest that HAPLN1 regulates the TGF-β signaling pathway to control collagen deposition via the TGF-β signaling pathway and mediates E-adhesion to control tumor growth. Thus, treatments that increase HAPLN1 levels may be a novel therapeutic option for CRC.

Autocrine Exosomal Fibulin-1 as a Target of MiR-1269b Induces Epithelial–Mesenchymal Transition in Proximal Tubule in Diabetic Nephropathy

Background: Diabetic nephropathy (DN) is an increasing threat to human health and is regarded to be the leading cause of end-stage renal disease worldwide. Exosomes deliver biomolecule massages and may play a key role in cell communication and the progression of DN.

Methods: A cross-disciplinary study, including in vivo, in vitro, and human studies, was conducted to explore the cross-talk within proximal tubular epithelial cells (PTECs) in DN. Exosomal protein from PTECs treated with high glucose (HG) was purified and examined using liquid chromatography–tandem mass spectrometry (LC-MS/MS). Next-generation sequencing (NGS) was utilized to analyze RNAs extracted from PTECs from a type 2 diabetic patient and a normal individual. HK-2 cells were used to assess exosomal protein and its modulation and biofunction in DN. Normal individuals and type 2 diabetic patients were enrolled, and nondiabetic db/m mice and diabetic db/db mice were used to validate the molecular mechanism of exosomes in DN.

Results: HG stimulated PTECs to increase Fibulin-1 (FBLN1) expression, and PTECs secreted FBLN1 through exosome delivery, thereby inducing epithelial–mesenchymal transition (EMT) in PTECs. Transcriptome analysis found that FBLN1 expression was modulated by miR-1269b, which was downregulated by HG in HK-2 cells. While transfection of miR-1269b reversed FBLN1-mediated EMT in PTECs, miR-1269b inhibitor modulated the phenotype of PTECs toward mesenchymal type under normal glucose (NG) condition. Most importantly, urinary FBLN1 and exosomal miR-1269b levels were correlated with the severity of kidney injury in type 2 diabetic patients.

Conclusion: This study demonstrated the communication within PTECs through exosome transmission in an autocrine pattern. MiR-1269b–FBLN1 epigenetic regulatory network could be a potential therapeutic strategy to prevent the progression of DN.

A microRNA-21-mediated SATB1/S100A9/NF-κB axis promotes chronic obstructive pulmonary disease pathogenesis

[Figure: see text].

iTRAQ-based quantitative proteomic analysis of the improved effects of total flavones of Dracocephalum Moldavica L. in chronic mountain sickness

To use isobaric tags for relative and absolute quantification (iTRAQ) technology to study the pathogenesis of chronic mountain sickness (CMS), identify biomarkers for CMS, and investigate the effect of total flavones of Dracocephalum moldavica L. (TFDM) on a rat model of CMS. We simulated high altitude hypobaric hypoxia conditions and generated a rat model of CMS. Following the administration of TFDM, we measured the pulmonary artery pressure and serum levels of hemoglobin (Hb), the hematocrit (Hct), and observed the structure of the pulmonary artery in experimental rats. Furthermore, we applied iTRAQ-labeled quantitative proteomics technology to identify differentially expressed proteins (DEPs) in the serum, performed bioinformatics analysis, and verified the DEPs by immunohistochemistry. Analysis showed that the pulmonary artery pressure, serum levels of Hb, and the Hct, were significantly increased in a rat model of CMS (P < 0.05). Pathological analysis of lung tissue and pulmonary artery tissue showed that the alveolar compartment had obvious hyperplasia and the pulmonary artery degree of muscularization was enhanced. Both pulmonary artery pressure and tissue morphology were improved following the administration of TFDM. We identified 532 DEPs by quantitative proteomics; gene ontology (GO)and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis further revealed that metabolic pathways associated with coagulation and complement play crucial roles in the occurrence of CMS. Immunohistochemistry verified that several DEPs (α-1-acid glycoprotein, collagen, fibulin, haptoglobin, PLTP, and TAGLN2) are important biological markers for CMS. Our analyses demonstrated that TFDM can improve CMS and exert action by influencing the metabolic pathways associated with coagulation and complement. This process relieves pulmonary artery pressure and improves lung function. We also identified that α-1-acid glycoprotein, collagen, fibulin, haptoglobin, PLTP, and TAGLN2 may represent potential biomarkers for CMS.

Time-resolved proteomic profiling of cigarette smoke-induced experimental chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is the third leading cause of illness and death worldwide. Current treatments aim to control symptoms with none able to reverse disease or stop its progression. We explored the major molecular changes in COPD pathogenesis.

METHODS

We employed quantitative label-based proteomics to map the changes in the lung tissue proteome of cigarette smoke-induced experimental COPD that is induced over 8 weeks and progresses over 12 weeks.

RESULTS

Quantification of 7324 proteins enabled the tracking of changes to the proteome. Alterations in protein expression profiles occurred in the induction phase, with 18 and 16 protein changes at 4- and 6-week time points, compared to age-matched controls, respectively. Strikingly, 269 proteins had altered expression after 8 weeks when the hallmark pathological features of human COPD emerge, but this dropped to 27 changes at 12 weeks with disease progression. Differentially expressed proteins were validated using other mouse and human COPD bronchial biopsy samples. Major changes in RNA biosynthesis (heterogeneous nuclear ribonucleoproteins C1/C2 [HNRNPC] and RNA-binding protein Musashi homologue 2 [MSI2]) and modulators of inflammatory responses (S100A1) were notable. Mitochondrial dysfunction and changes in oxidative stress proteins also occurred.

CONCLUSION

We provide a detailed proteomic profile, identifying proteins associated with the pathogenesis and disease progression of COPD establishing a platform to develop effective new treatment strategies.

Macrophage-stroma interactions in fibrosis: biochemical, biophysical, and cellular perspectives

Fibrosis results from aberrant wound healing and is characterized by an accumulation of extracellular matrix, impairing the function of an affected organ. Increased deposition of extracellular matrix proteins, disruption of matrix degradation, but also abnormal post-translational modifications alter the biochemical composition and biophysical properties of the tissue microenvironment - the stroma. Macrophages are known to play an important role in wound healing and tissue repair, but the direct influence of fibrotic stroma on macrophage behaviour is still an under-investigated element in the pathogenesis of fibrosis. In this review, the current knowledge on interactions between macrophages and (fibrotic) stroma will be discussed from biochemical, biophysical, and cellular perspectives. Furthermore, we provide future perspectives with regard to how macrophage-stroma interactions can be examined further to ultimately facilitate more specific targeting of these interactions in the treatment of fibrosis. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Pathophysiological regulation of lung function by the free fatty acid receptor FFA4

Increased prevalence of inflammatory airway diseases including asthma and chronic obstructive pulmonary disease (COPD) together with inadequate disease control by current frontline treatments means that there is a need to define therapeutic targets for these conditions. Here, we investigate a member of the G protein-coupled receptor family, FFA4, that responds to free circulating fatty acids including dietary omega-3 fatty acids found in fish oils. We show that FFA4, although usually associated with metabolic responses linked with food intake, is expressed in the lung where it is coupled to G_q/11 signaling. Activation of FFA4 by drug-like agonists produced relaxation of murine airway smooth muscle mediated at least in part by the release of the prostaglandin E₂ (PGE₂) that subsequently acts on EP₂ prostanoid receptors. In normal mice, activation of FFA4 resulted in a decrease in lung resistance. In acute and chronic ozone models of pollution-mediated inflammation and house dust mite and cigarette smoke-induced inflammatory disease, FFA4 agonists acted to reduce airway resistance, a response that was absent in mice lacking expression of FFA4. The expression profile of FFA4 in human lung was similar to that observed in mice, and the response to FFA4/FFA1 agonists similarly mediated human airway smooth muscle relaxation ex vivo. Our study provides evidence that pharmacological targeting of lung FFA4, and possibly combined activation of FFA4 and FFA1, has in vivo efficacy and might have therapeutic value in the treatment of bronchoconstriction associated with inflammatory airway diseases such as asthma and COPD.

The role of osteoprotegerin (OPG) in fibrosis: its potential as a biomarker and/or biological target for the treatment of fibrotic diseases

Fibrosis is defined by excessive formation and accumulation of extracellular matrix proteins, produced by myofibroblasts, that supersedes normal wound healing responses to injury and results in progressive architectural remodelling. Fibrosis is often detected in advanced disease stages when an organ is already severely damaged and can no longer function properly. Therefore, there is an urgent need for reliable and easily detectable markers to identify and monitor fibrosis onset and progression as early as possible; this will greatly facilitate the development of novel therapeutic strategies. Osteoprotegerin (OPG), a well-known regulator of bone extracellular matrix and most studied for its role in regulating bone mass, is expressed in various organs and functions as a decoy for receptor activator of nuclear factor kappa-B ligand (RANKL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Recently, OPG has been linked to fibrosis and fibrogenesis, and has been included in a panel of markers to diagnose liver fibrosis. Multiple studies now suggest that OPG may be a general biomarker suitable for detection of fibrosis and/or monitoring the impact of fibrosis treatment. This review summarizes our current understanding of the role of OPG in fibrosis and will discuss its potential as a biomarker and/or novel therapeutic target for fibrosis.

Necroptosis Signalling Promotes Inflammation, Airway Remodelling and Emphysema in COPD

RATIONALE

Necroptosis, mediated by RIPK3 and MLKL, is a form of regulated necrosis that can drive tissue inflammation and destruction, however its contribution to COPD pathogenesis is poorly understood.

OBJECTIVES

To determine the role of necroptosis in COPD.

METHODS

Levels of RIPK3, MLKL and activated phospho-MLKL were measured in lung tissues of COPD patients and non-COPD controls. Necroptosis-related mRNA and proteins and cell death were examined in the lungs and pulmonary macrophages of mice with cigarette smoke (CS)-induced experimental COPD. The responses of Ripk3- and Mlkl-deficient (-/-) mice to CS exposure were compared to wild-type mice. Combined inhibition of apoptosis (pan-caspase inhibitor qVD-OPh) and necroptosis (Mlkl-/- mice) was assessed.

MEASUREMENTS AND MAIN RESULTS

Protein levels of MLKL and pMLKL but not RIPK3 were increased in lung tissues of COPD patients compared to never smokers or smoker non-COPD controls. Necroptosis-related mRNA and protein levels were increased in lung tissue and macrophages in CS-exposed mice/experimental COPD. Ripk3 or Mlkl deletion prevented airway inflammation in response to acute CS-exposure. Ripk3 deficiency reduced airway inflammation and remodelling and development of emphysematous pathology following chronic CS-exposure. Mlkl deletion and qVD-OPh treatment reduced chronic CS-induced airway inflammation, but only Mlkl deletion prevented airway remodelling and emphysema. Ripk3 or Mlkl deletion and qVD-OPh treatment reduced CS-induced lung cell death.

CONCLUSIONS

Necroptosis is induced by CS exposure and increased in COPD patient lungs and experimental COPD. Inhibiting necroptosis attenuates CS-induced airway inflammation, airway remodelling and emphysema. Targeted inhibition of necroptosis is a potential therapeutic strategy in COPD.

Implications for Extracellular Matrix Interactions With Human Lung Basal Stem Cells in Lung Development, Disease, and Airway Modeling

The extracellular matrix (ECM) is not simply a quiescent scaffold. This three-dimensional network of extracellular macromolecules provides structural, mechanical, and biochemical support for the cells of the lung. Throughout life, the ECM forms a critical component of the pulmonary stem cell niche. Basal cells (BCs), the primary stem cells of the airways capable of differentiating to all luminal cell types, reside in close proximity to the basolateral ECM. Studying BC-ECM interactions is important for the development of therapies for chronic lung diseases in which ECM alterations are accompanied by an apparent loss of the lung's regenerative capacity. The complexity and importance of the native ECM in the regulation of BCs is highlighted as we have yet to create an in vitro culture model that is capable of supporting the long-term expansion of multipotent BCs. The interactions between the pulmonary ECM and BCs are, therefore, a vital component for understanding the mechanisms regulating BC stemness during health and disease. If we are able to replicate these interactions in airway models, we could significantly improve our ability to maintain basal cell stemness ex vivo for use in in vitro models and with prospects for cellular therapies. Furthermore, successful, and sustained airway regeneration in an aged or diseased lung by small molecules, novel compounds or via cellular therapy will rely upon both manipulation of the airway stem cells and their immediate niche within the lung. This review will focus on the current understanding of how the pulmonary ECM regulates the basal stem cell function, how this relationship changes in chronic disease, and how replicating native conditions poses challenges for ex vivo cell culture.

A Review of CXCL1 in Cardiac Fibrosis

Chemokine C-X-C motif ligand-1 (CXCL1), principally expressed in neutrophils, macrophages and epithelial cells, is a valid pro-inflammatory factor which performs an important role in mediating the infiltration of neutrophils and monocytes/macrophages. Elevated serum level of CXCL1 is considered a pro-inflammatory reaction by the organism. CXCL1 is also related to diverse organs fibrosis according to relevant studies. A growing body of evidence suggests that CXCL1 promotes the process of cardiac remodeling and fibrosis. Here, we review structure and physiological functions of CXCL1 and recent progress on the effects and mechanisms of CXCL1 in cardiac fibrosis. In addition, we explore the role of CXCL1 in the fibrosis of other organs. Besides, we probe the possibility that CXCL1 can be a therapeutic target for the treatment of cardiac fibrosis in cardiovascular diseases.

Fibrotic expression profile analysis reveals repurposed drugs with potential anti-fibrotic mode of action

Fibrotic diseases cover a spectrum of systemic and organ-specific maladies that affect a large portion of the population, currently without cure. The shared characteristic these diseases feature is their uncontrollable fibrogenesis deemed responsible for the accumulated damage in the susceptible tissues. Idiopathic Pulmonary Fibrosis, an interstitial lung disease, is one of the most common and studied fibrotic diseases and still remains an active research target. In this study we highlight unique and common (i) genes, (ii) biological pathways and (iii) candidate repurposed drugs among 9 fibrotic diseases. We identify 7 biological pathways involved in all 9 fibrotic diseases as well as pathways unique to some of these diseases. Based on our Drug Repurposing results, we suggest captopril and ibuprofen that both appear to slow the progression of fibrotic diseases according to existing bibliography. We also recommend nafcillin and memantine, which haven't been studied against fibrosis yet, for further wet-lab experimentation. We also observe a group of cardiomyopathy-related pathways that are exclusively highlighted for Oral Submucous Fibrosis. We suggest digoxin to be tested against Oral Submucous Fibrosis, since we observe cardiomyopathy-related pathways implicated in Oral Submucous Fibrosis and there is bibliographic evidence that digoxin may potentially clear myocardial fibrosis. Finally, we establish that Idiopathic Pulmonary Fibrosis shares several involved genes, biological pathways and candidate inhibiting-drugs with Dupuytren's Disease, IgG4-related Disease, Systemic Sclerosis and Cystic Fibrosis. We propose that treatments for these fibrotic diseases should be jointly pursued.

Therapeutic targets in lung tissue remodelling and fibrosis

Structural changes involving tissue remodelling and fibrosis are major features of many pulmonary diseases, including asthma, chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Abnormal deposition of extracellular matrix (ECM) proteins is a key factor in the development of tissue remodelling that results in symptoms and impaired lung function in these diseases. Tissue remodelling in the lungs is complex and differs between compartments. Some pathways are common but tissue remodelling around the airways and in the parenchyma have different morphologies. Hence it is critical to evaluate both common fibrotic pathways and those that are specific to different compartments; thereby expanding the understanding of the pathogenesis of fibrosis and remodelling in the airways and parenchyma in asthma, COPD and IPF with a view to developing therapeutic strategies for each. Here we review the current understanding of remodelling features and underlying mechanisms in these major respiratory diseases. The differences and similarities of remodelling are used to highlight potential common therapeutic targets and strategies. One central pathway in remodelling processes involves transforming growth factor (TGF)-β induced fibroblast activation and myofibroblast differentiation that increases ECM production. The current treatments and clinical trials targeting remodelling are described, as well as potential future directions. These endeavours are indicative of the renewed effort and optimism for drug discovery targeting tissue remodelling and fibrosis.

Proteomics of serum extracellular vesicles identifies a novel COPD biomarker, fibulin-3 from elastic fibres

There is an unmet need for novel biomarkers in the diagnosis of multifactorial COPD. We applied next-generation proteomics to serum extracellular vesicles (EVs) to discover novel COPD biomarkers.

EVs from 10 patients with COPD and six healthy controls were analysed by tandem mass tag-based non-targeted proteomics, and those from elastase-treated mouse models of emphysema were also analysed by non-targeted proteomics. For validation, EVs from 23 patients with COPD and 20 healthy controls were validated by targeted proteomics.

Using non-targeted proteomics, we identified 406 proteins, 34 of which were significantly upregulated in patients with COPD. Of note, the EV protein signature from patients with COPD reflected inflammation and remodelling. We also identified 63 upregulated candidates from 1956 proteins by analysing EVs isolated from mouse models. Combining human and mouse biomarker candidates, we validated 45 proteins by targeted proteomics, selected reaction monitoring. Notably, levels of fibulin-3, tripeptidyl-peptidase 2, fibulin-1, and soluble scavenger receptor cysteine-rich domain-containing protein were significantly higher in patients with COPD. Moreover, six proteins; fibulin-3, tripeptidyl-peptidase 2, UTP-glucose-1-phosphate uridylyl transferase, CD81, CD177, and oncoprotein-induced transcript 3, were correlated with emphysema. Upregulation of fibulin-3 was confirmed by immunoblotting of EVs and immunohistochemistry in lungs. Strikingly, fibulin-3 knockout mice spontaneously developed emphysema with age, as evidenced by alveolar enlargement and elastin destruction.

We discovered potential pathogenic biomarkers for COPD using next-generation proteomics of EVs. This is a novel strategy for biomarker discovery and precision medicine.

This study identified novel biomarkers for COPD using next-generation proteomics of serum extracellular vesicles. Notably, the expression of fibulin-3 is correlated with lung function and emphysema. This could be useful for personalised medicine.https://bit.ly/2JfRCgk

Asthma-COPD overlap: current understanding and the utility of experimental models

Pathological features of both asthma and COPD coexist in some patients and this is termed asthma-COPD overlap (ACO). ACO is heterogeneous and patients exhibit various combinations of asthma and COPD features, making it difficult to characterise the underlying pathogenic mechanisms. There are no controlled studies that define effective therapies for ACO, which arises from the lack of international consensus on the definition and diagnostic criteria for ACO, as well as scant in vitro and in vivo data. There remain unmet needs for experimental models of ACO that accurately recapitulate the hallmark features of ACO in patients. The development and interrogation of such models will identify underlying disease-causing mechanisms, as well as enabling the identification of novel therapeutic targets and providing a platform for assessing new ACO therapies. Here, we review the current understanding of the clinical features of ACO and highlight the approaches that are best suited for developing representative experimental models of ACO.

Understanding the pathogenesis of asthma-COPD overlap is critical for improving therapeutic approaches. We present current knowledge on asthma-COPD overlap and the requirements for developing an optimal animal model of disease.https://bit.ly/3lsjyvm