Ncf1 Governs Immune Niches in the Lung to Mediate Pulmonary Inflammation in Mice

Multi-omic integration reveals alterations in nasal mucosal biology that mediate air pollutant effects on allergic rhinitis

BACKGROUND

Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa.

METHODS

In a case-control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole-genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis.

RESULTS

Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro-inflammatory TGF-β1 signaling, and the regulation of myeloid immune cell function.

CONCLUSIONS

Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa.

Integrative analysis of network pharmacology and proteomics reveal the protective effect of Xiaoqinglong Decotion on neutrophilic asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaoqinglong Decotion (XQLD) is a commonly used Chinese herbal formula in clinical practice, especially for allergic diseases such as asthma. However, its intrinsic mechanism for the treatment of neutrophilic asthma (NA) remains unclear.

AIM OF THE STUDY

The aim of this study was to evaluate the efficacy and potential mechanisms of XQLD on NA using network pharmacology and in vivo experiments.

MATERIALS AND METHODS

First, the active compounds, potential targets and mechanisms of XQLD against NA were initially elucidated by network pharmacology. Then, OVA/CFA-induced NA mice were treated with XQLD to assess its efficacy. Proteins were then analyzed and quantified using a Tandem Mass Tags approach for differentially expressed proteins (DEPs) to further reveal the mechanisms of NA treatment by XQLD. Finally, the hub genes, critical DEPs and potential pathways were validated.

RESULTS

176 active compounds and 180 targets against NA were identified in XQLD. Protein-protein interaction (PPI) network revealed CXCL10, CX3CR1, TLR7, NCF1 and FABP4 as hub genes. In vivo experiments showed that XQLD attenuated inflammatory infiltrates, airway mucus secretion and remodeling in the lungs of NA mice. Moreover, XQLD significantly alleviated airway neutrophil inflammation in NA mice by decreasing the expression of IL-8, MPO and NE. XQLD also reduced the levels of CXCL10, CX3CR1, TLR7, NCF1 and FABP4, which are closely associated with neutrophil inflammation. Proteomics analysis identified 28 overlapping DEPs in the control, NA and XQLD groups, and we found that XQLD inhibited ferroptosis signal pathway (elevated GPX4 and decreased ASCL3) as well as the expression of ARG1, MMP12 and SPP1, while activating the Rap1 signaling pathway.

CONCLUSION

This study revealed that inhibition of ARG1, MMP12 and SPP1 expression as well as ferroptosis pathways, and activation of the Rap1 signaling pathway contribute to the therapeutic effect of XQLD on NA.

Tuft cells and fibroblasts promote thymus regeneration through ILC2-mediated type 2 immune response

The thymus is a primary lymphoid organ that is essential for the establishment of adaptive immunity through generation of immunocompetent T cells. In response to various stress signals, the thymus undergoes acute but reversible involution. However, the mechanisms governing its recovery are incompletely understood. Here, we used a dexamethasone-induced acute thymic involution mouse model to investigate how thymic hematopoietic cells (excluding T cells) contribute to thymic regeneration. scRNA-seq analysis revealed marked transcriptional and cellular changes in various thymic populations and highlighted thymus-resident innate lymphoid cells type 2 (ILC2) as a key cell type involved in the response to damage. We identified that ILC2 are activated by the alarmins IL-25 and IL-33 produced in response to tissue damage by thymic tuft cells and fibroblasts, respectively. Moreover, using mouse models deficient in either tuft cells and/or IL-33, we found that these alarmins are required for effective thymus regeneration after dexamethasone-induced damage. We also demonstrate that upon their damage-dependent activation, thymic ILC2 produce several effector molecules linked to tissue regeneration, such as amphiregulin and IL-13, which in turn promote thymic epithelial cell differentiation. Collectively, our study elucidates a previously undescribed role for thymic tuft cells and fibroblasts in thymus regeneration through activation of the type 2 immune response.

A Network Pharmacology Approach and Validation Experiments to Investigate the Mechanism of Wen-Dan Decoction in the Treatment of SINFH

INTRODUCTION

Steroid-induced necrosis of the femoral head (SINFH) is a femoral head necrotic disease caused by prolonged use of hormones. Wen-Dan decoction is used in Chinese clinical practice for the treatment of steroid-induced necrosis of the femoral head (SINFH). However, the mechanism and active compounds of Wen-Dan decoction used to treat SINFH are not well understood.

OBJECTIVES

We studied the mechanism of action of Wen-Dan decoction in treating steroidinduced necrosis of the femoral head (SINFH) via network pharmacology and in vivo experiments.

METHODS

The active compounds of Wen-Dan decoction and SINFH-related target genes were identified through public databases. Then, network pharmacological analysis was conducted to explore the potential key active compounds, core targets and biological processes of Wen-Dan decoction in SINFH. The potential mechanisms of Wen-Dan decoction in SINFH obtained by network pharmacology were validated through in vivo experiments.

RESULTS

We identified 608 DEGs (differentially expressed genes) (230 upregulated, 378 downregulated) in SINFH. GO analysis revealed that the SINFH-related genes were mainly involved in neutrophil activation and the immune response. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis showed that the SINFH-related genes were mainly associated with cytokine receptor interactions, lipids, atherosclerosis, and tuberculosis. We identified 147 active ingredients of Wen-Dan decoction; the core ingredient was quercetin, and licorice was an active ingredient. Moreover, 277 target genes in the treatment of SINFH with Wen-Dan decoction were identified, and NCF1, PTGS2, and RUNX2 were selected as core target genes. QRT-PCR of peripheral blood from SINFH patients showed higher levels of PGTS2 and NCF1 and showed lower levels of RUNX2 compared to controls. QRT-PCR analysis of peripheral blood and femoral bone tissue from a mouse model of SINFH showed higher levels of PGTS2 and NCF1 and lower levels of RUNX2 in the experimental animals than the controls, which was consistent with the bioinformatics results. HE, immunohistochemistry, and TUNEL staining confirmed a significant reduction in hormone-induced femoral head necrosis in the quercetintreated mice. HE, immunohistochemistry, and TUNEL staining confirmed significant improvement in hormone-induced femoral head necrosis in the quercetin-treated mice.

CONCLUSION

We provide new insights into the genes and related pathways involved in SINFH and report that PTGS2, RUNX2, and NCF1 are potential drug targets. Quercetin improved SINFH by promoting osteogenesis and inhibiting apoptosis.

Bronchial Asthma, Airway Remodeling and Lung Fibrosis as Successive Steps of One Process

Bronchial asthma is a heterogeneous disease characterized by persistent respiratory system inflammation, airway hyperreactivity, and airflow obstruction. Airway remodeling, defined as changes in airway wall structure such as extensive epithelial damage, airway smooth muscle hypertrophy, collagen deposition, and subepithelial fibrosis, is a key feature of asthma. Lung fibrosis is a common occurrence in the pathogenesis of fatal and long-term asthma, and it is associated with disease severity and resistance to therapy. It can thus be regarded as an irreversible consequence of asthma-induced airway inflammation and remodeling. Asthma heterogeneity presents several diagnostic challenges, particularly in distinguishing between chronic asthma and other pulmonary diseases characterized by disruption of normal lung architecture and functions, such as chronic obstructive pulmonary disease. The search for instruments that can predict the development of irreversible structural changes in the lungs, such as chronic components of airway remodeling and fibrosis, is particularly difficult. To overcome these challenges, significant efforts are being directed toward the discovery and investigation of molecular characteristics and biomarkers capable of distinguishing between different types of asthma as well as between asthma and other pulmonary disorders with similar structural characteristics. The main features of bronchial asthma etiology, pathogenesis, and morphological characteristics as well as asthma-associated airway remodeling and lung fibrosis as successive stages of one process will be discussed in this review. The most common murine models and biomarkers of asthma progression and post-asthmatic fibrosis will also be covered. The molecular mechanisms and key cellular players of the asthmatic process described and systematized in this review are intended to help in the search for new molecular markers and promising therapeutic targets for asthma prediction and therapy.

Interferons as negative regulators of ILC2s in allergic lung inflammation and respiratory viral infections

Group 2 innate lymphoid cells (ILC2s), characterized by a lack of antigen receptors, have been regarded as an important component of type 2 pulmonary immunity. Analogous to Th2 cells, ILC2s are capable of releasing type 2 cytokines and amphiregulin, thus playing an essential role in a variety of diseases, such as allergic diseases and virus-induced respiratory diseases. Interferons (IFNs), an important family of cytokines with potent antiviral effects, can be triggered by microbial products, microbial exposure, and pathogen infections. Interestingly, the past few years have witnessed encouraging progress in revealing the important role of IFNs and IFN-producing cells in modulating ILC2 responses in allergic lung inflammation and respiratory viral infections. This review underscores recent progress in understanding the role of IFNs and IFN-producing cells in shaping ILC2 responses and discusses disease phenotypes, mechanisms, and therapeutic targets in the context of allergic lung inflammation and infections with viruses, including influenza virus, rhinovirus (RV), respiratory syncytial virus (RSV), and severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2).

Genome-Wide Detection and Analysis of Copy Number Variation in Anhui Indigenous and Western Commercial Pig Breeds Using Porcine 80K SNP BeadChip

Copy number variation (CNV) is an important class of genetic variations widely associated with the porcine genome, but little is known about the characteristics of CNVs in foreign and indigenous pig breeds. We performed a genome-wide comparison of CNVs between Anhui indigenous pig (AHIP) and Western commercial pig (WECP) breeds based on data from the Porcine 80K SNP BeadChip. After analysis using the PennCNV software, we detected 3863 and 7546 CNVs in the AHIP and WECP populations, respectively. We obtained 225 (loss: 178, gain: 47) and 379 (loss: 293, gain: 86) copy number variation regions (CNVRs) randomly distributed across the autosomes of the AHIP and WECP populations, accounting for 10.90% and 22.57% of the porcine autosomal genome, respectively. Functional enrichment analysis of genes in the CNVRs identified genes related to immunity (FOXJ1, FOXK2, MBL2, TNFRSF4, SIRT1, NCF1) and meat quality (DGAT1, NT5E) in the WECP population; these genes were a loss event in the WECP population. This study provides important information on CNV differences between foreign and indigenous pig breeds, making it possible to provide a reference for future improvement of these breeds and their production performance.

A missense variant in NCF1 is associated with susceptibility to unexplained recurrent spontaneous abortion

Unexplained recurrent spontaneous abortion (URSA) is a major concern in reproductive medicine. Neutrophil cytosolic factor 1 (NCF1) polymorphisms leading to low production of reactive oxygen species (ROS) are strongly associated with autoimmune diseases. We investigated the association of the missense single nucleotide polymorphism (SNP) rs201802880 (NCF1-339) in NCF1 with URSA and explored its function. We performed NCF1-339 SNP genotyping of samples from 152 Chinese patients with URSA and 72 healthy controls using nested PCR and TaqMan assays. ROS production and RELA (NF-κB subunit) expression in the blood of participants with different NCF1-339 genotypes were determined. The frequencies of the wild-type (GG) and mutant (GA) genotypes remarkably differed between the URSA and control groups. The mutant genotype was associated with an increased risk of recurrent abortion. Furthermore, ROS levels in the URSA group with the GG genotype were significantly higher than those in the group with the GA genotype (p < 0.05). RELA expression in URSA patients with the GA genotype was considerably higher than that in control individuals with the GG genotype. These findings indicate that mutations in NCF1 may increase the risk of URSA via the NADP/ROS/NF-κB signaling pathway, which has implications for the diagnosis and treatment of URSA.