Receptor Signaling Research Articles

Heritability, signal perception and autoregulation of root nodulation in chickpea

Chickpea (Cicer arietinum L.) establishes symbiotic interactions with Mesorhizobium to develop root nodules where nitrogen fixation occurs. This symbiotic relationship can fix atmospheric nitrogen (N2) up to 140 kg N/ha that contribute nearly 80% nitrogen requirement of the crop. Global researchers had revealed the existence of natural variations in chickpea germplasm for nodulation traits with high heritability. Surprisingly, the contribution of environmental variation is too low for Biological Nitrogen Fixation (BNF) traits and high broad-sense heritability (>60) was observed for early nodulation, late nodule senescence and high nodule number traits. Correlation studies indicated a strong positive correlation between nodule number at flowering stage with total nodule weight and plant biomass and seed protein content. Nod Factor receptors in chickpea (CaNFR1 and CaNFR5) are characterized recently that forms phylogenetically distinct group along with M. truncatula, P. sativum, and L. japonicus. Critical role of cytokinin signalling through members of two component system (TCS) in nodulation was investigated in chickpea. The chickpea ortholog CaHK19 was the master spigot of cytokinin perception in chickpea. The co-expression pattern of CaHKs and CaNIN clearly indicated a link between cytokinin perception and downstream expression of CaNIN in chickpea as earlier established in Medicago. Genes involved in AON pathway are partially revealed in chickpea. CaRND1, CaRDN2, and CaRDN3 (C. arietinum Root-Determined Nodulation) function as receptors for signals produced from the roots. Revealing the molecular basis of root nodule organogenesis and their regulatory mechanisms along with identification of potential genetic stock will help on breeding or engineering chickpea genotypes with high symbiotic efficiency, extended nitrogen fixation and high symbiotic efficiency make grain legumes as nitrogen fixing factories to fertilize the soil in a sustainable way.

Optimal timing for initiating androgen receptor signaling inhibitor therapy in patients with nonmetastatic castration-resistant prostate cancer: a multicenter collaborative study.

We determined the optimal timing for initiating androgen receptor signaling inhibitor (ARSI) therapy in patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) and assessed its impact on oncological outcomes. This retrospective study included 145 nmCRPC patients who received enzalutamide, apalutamide or darolutamide at the Jikei University Hospital or its affiliated institutions between May 2014 and November 2022. Patients were stratified based on prostate-specific antigen (PSA) doubling time (PSADT) at CRPC diagnosis and PSA levels at ARSI initiation. Oncological outcomes, including progression-free survival (PFS), metastasis-free survival (MFS), cancer-specific survival and overall survival, were assessed using the Kaplan-Meier curve and Cox regression analysis. The median age of the patients was 73 (interquartile range [IQR]: 52-88) years, and the median follow-up duration was 36 (IQR: 2-104) months. The median PSA level at ARSI initiation was 5.4 (IQR: 2.2-48) ng/ml, and 44.8% of patients had a PSADT <3months. Multivariate analysis revealed that PSADT and PSA levels at ARSI initiation were independent MFS predictors. Patients with a PSADT ≤3months and a PSA level≥5.4ng/ml experienced significantly reduced PFS and MFS. Notably, ARSI initiation at a PSA level ≥5.4ng/ml was associated with worse outcomes, suggesting the potential benefit of earlier intervention. Patients with rapid PSADT are at increased risk of early disease progression, suggesting that immediate treatment may be warranted. In addition, initiating therapy at a PSA level <5.4ng/ml may be associated with improved patient outcomes in patients with low PSADT.

A novel biomimetic nanovesicle containing caffeic acid-coupled carbon quantum dots for the the treatment of Alzheimer's disease via nasal administration.

Alzheimer's disease (AD) is a common neurodegenerative disease characterized by progressive cognitive and physical impairment. Neuroinflammation is related to AD, and the misfolding and aggregation of amyloid protein in the brain creates an inflammatory microenvironment. Microglia are the predominant contributors to neuroinflammation, and abnormal activation of microglia induces the release of a large amount of inflammatory factors, promotes neuronal apoptosis, and leads to cognitive impairment. In this study, we used microglial membranes containing caffeic acid-coupled carbon quantum dots to prepare a novel biomimetic nanocapsule (CDs-CA-MGs) for the treatment of AD. The application of CDs-CA-MGs via nasal administration can bypass the blood‒brain barrier (BBB) and directly target the site of inflammation. After treatment with CDs-CA-MGs, AD mice showed reduced inflammation in the brain, decreased neuronal apoptosis, and significantly improved learning and memory abilities. In addition, CDs-CA-MGs affect inflammation-related JAK-STAT and Toll-like receptor signaling pathways in AD mice. CDs-CA-MGs significantly downregulated interleukins (IL-1β and IL-6) and tumor necrosis factor (TNF-α). This finding suggested that CDs-CA-MGs may improve cognitive impairment by modulating inflammatory responses. In conclusion, the use of CDs-CA-MGs provides a possible therapeutic strategy for the treatment of AD.

Weaker neuroligin 2 - neurexin 1β interaction tethers membranes and signal synaptogenesis through clustering.

Single-pass transmembrane proteins neuroligin (NL) and neurexin (NRX) constitute a pair of synaptic adhesion molecules (SAMs) that are essential for the formation of functional synapses. Binding affinities vary by ∼ 1000 folds between arrays of NL and NRX subtypes, which contribute to chemical and spatial specificities. Current structures are obtained with truncated extracellular domains of NL and NRX and are limited to the higher-affinity NL1/4-NRX complexes. How NL-NRX interaction leads to functional synapses remains unknown. Here we report structures of full-length NL2 alone, and in complex with NRX1β in several conformations, which has the lowest affinity among major NL-NRX subtypes. We show how conformational flexibilities may help in adapting local membrane geometry, and reveal mechanisms underlying variations in NL-NRX affinities modulation. We further show that, despite lower affinity, NL2-NRX1β interaction alone is capable of tethering different lipid membranes in total reconstitution, and that NL2 and NRX1β cluster at inter-cellular junctions without the need of other synaptic components. In addition, NL2 combines with the master post-synaptic scaffolding protein gephyrin and clusters neurotransmitter receptors at cellular membrane. These findings suggest dual roles of NL2 - NRX1β interaction - both as mechanical tether, and as signaling receptors, to ensure correct spatial and chemical coordination between two cells to generate function synapses.

Exploring the Key Pathogenesis and Potential Intervention Targets of Sulforaphane in Acute Kidney Injury in Sepsis Based on Bioinformatics.

The objective was to use bioinformatics to analyze the potential key genes involved in the mechanism of sulforaphane's protective effects in sepsis-associated acute kidney injury (SA-AKI) and to identify potential intervention targets. Gene Expression Omnibus (GEO) gene chip datasets containing gene expression profiles from kidney tissues of SA-AKI patients and normal controls were selected. Upregulated differentially expressed genes (DEGs) were identified using GEO2R. Protein-protein interaction (PPI), GO, and KEGG enrichment analyses were performed. Allyl isothiocyanate's target genes were analyzed in the ChEMBL database, and intersections with the above DEGs were presented in Venn diagrams. Rat tissues were examined for FKBP1A expression using qRT-PCR. A total of 17 DEGs related to SA-AKI were obtained (|log fold change| > 0 and P < .05). KEGG pathway analysis indicated that the primary pathways linked to the elevated DEGs were glycogen breakdown, leukocyte trans-endothelial migration, and T-cell receptor, TNF, and NF-κB signaling. The module and PPI network analysis of common DEGs revealed one cluster and four candidate genes, including OASL, TRRAP, FKBP1A, and BANF. ChEMBL database analysis identified 339 target genes for allyl isothiocyanate, and the intersection with upregulated DEGs related to SA-AKI injury yielded two co-expressed genes, FKBP1A and TRRAP. According to the findings of the qRT-PCR assay, the kidney tissues of the model cohort showed significantly higher expression levels of FKBP1A mRNA than the control cohort (P = .0142). Allyl isothiocyanate may alleviate SA-AKI injury by targeting FKBP1/NF-κB.

Voluntary Exercise Attenuates Tumor Growth in a Preclinical Model of Castration-Resistant Prostate Cancer.

To examine the effects of voluntary exercise training on tumor growth and explore the underlying intratumoral molecular pathways and processes responsible for the beneficial effects of VWR on tumor initiation and progression in a mouse model of Castration-Resistant Prostate Cancer (CRPC). Male immunodeficient mice (SCID) were castrated and subcutaneously inoculated with human CWR-22RV1 cancer cells to construct CRPC xenograft model before randomly assigned to either voluntary wheel running (VWR) or sedentary (SED) group (n=6/group). After three weeks, tumor tissues were collected. Tumor size was measured and calculated. mRNA expression of markers of DNA replication, Androgen Receptor (AR) signaling, and mitochondrial dynamics was determined by RT-PCR. Protein expression of mitochondrial content and dynamics was determined by western blotting. Finally, RNA-sequencing analysis was performed in the tumor tissues. Voluntary wheel running resulted in smaller tumor volume at the initial stage and attenuated tumor progression throughout the time course (P < 0.05). The reduction of tumor volume in VWR group was coincided with lower mRNA expression of DNA replication markers ( MCM2 , MCM6 , and MCM7 ), AR signaling ( ELOVL5 and FKBP5 ) and regulatory proteins of mitochondrial fission (Drp1 and Fis1) and fusion (MFN1 and OPA1) when compared to the SED group (P<0.05). More importantly, RNA sequencing data further revealed that pathways related to pathways related to angiogenesis, extracellular matrix formation and endothelial cell proliferation were downregulated. Three weeks of VWR was effective in delaying tumor initiation and progression, which coincided with reduced transcription of DNA replication, AR signaling targets and mitochondrial dynamics. We further identified reduced molecular pathways/processes related to angiogenesis that may be responsible for the delayed tumor initiation and progression by VWR.

TMT-based quantitative proteomics unveils the protective mechanism of Polygonatum sibiricum polysaccharides on septic acute liver injury

Polygonatum sibiricum polysaccharides (PSP) has been shown to possess multiple pharmacological functions. Our previous study found that PSP could protect against acute liver injury during sepsis via inhibiting inflammatory response. However, the underlying molecular mechanism by which PSP alleviates septic acute liver injury (SALI) remains unknown. Herein, TMT-based quantitative proteomics was utilized to explore the essential pathways and proteins involved in the protective effects of PSP on SALI. The results revealed that 632 and 176 differentially expressed proteins (DEPs) were identified in Model_vs_Control and PSP_vs_Model, respectively. GO annotation showed similar trends, suggesting that these DEPs were primarily involved in the cellular anatomical entity in Cellular Component, the cellular processe and the biological regulation in Biological Process, the binding and the catalytic activity in Molecular Function. Meanwhile, KEGG enrichment analysis implied that four common pathways, including the NF-κB signaling pathway, the IL-17 signaling pathway, the TNF signaling pathway and the Toll-like receptor signaling pathway, were closely associated with the pathogenesis of sepsis among the top 20 remarkably enriched pathways in Model_vs_Control_up and PSP_vs_Model_down. Moreover, the levels of several common DEPs, including TLR2, IKKi, JunB and CXCL9, were validated by WB, which was in line with the results of proteomics. Therefore, the protective effects of PSP on SALI might exert via blocking the above-mentioned inflammation pathways.Significance: PSP, recognized as a key component of Polygonatum sibiricum, exhibits a range of pharmacological functions. Our previous study found that PSP could protect against SALI, yet failing to clarify the mechanism of action. To reveal the underlying molecular mechanism involved in the protective effects of PSP on SALI, a TMT-based quantitative proteomic analysis was performed to detect and analyse the DEPs in liver tissue among the control group, the model group and the PSP group in this study. The results provide theoretical references for exploring the action mechanism of drugs and facilitate the comprehensive utilization of PSP. SignificancePSP have been identified as the most crucial components of Polygonatum sibiricum with various pharmacological functions. Our previous study found that PSP could protect against SALI, but the mechanism of action remains unknown. To reveal the underlying molecular mechanism involved in the protective effects of PSP on SALI, a TMT-based quantitative proteomic analysis was performed to detect and analyse the DEPs in liver tissue among the control group, the model group and the PSP group in this study. The results provide theoretical references for exploring the action mechanism of drugs and facilitate the comprehensive utilization of PSP.

Reverse hierarchical DED assembly in the cFLIP-procaspase-8 and cFLIP-procaspase-8-FADD complexes

cFLIP, a master anti-apoptotic regulator, targets the FADD-induced DED complexes of procaspase-8 in death receptor and ripoptosome signaling pathways. Several tumor cells maintain relatively high levels of cFLIP in achieving their immortality. However, understanding the three-dimensional regulatory mechanism initiated or mediated by elevated levels of cFLIP has been limited by the absence of the atomic coordinates for cFLIP-induced DED complexes. Here we report the crystal plus cryo-EM structures to uncover an unconventional mechanism where cFLIP and procaspase-8 autonomously form a binary tandem DED complex, independent of FADD. This complex gains the ability to recruit FADD, thereby allosterically modulating cFLIP assembly and partially activating caspase-8 for RIPK1 cleavage. Our structure-guided mutagenesis experiments provide critical insights into these regulatory mechanisms, elucidating the resistance to apoptosis and necroptosis in achieving immortality. Finally, this research offers a unified model for the intricate bidirectional hierarchy-based processes using multiprotein helical assembly to govern cell fate decisions.

Berberine Ameliorates High-fat-induced Insulin Resistance in HepG2 Cells by Modulating PPARs Signaling Pathway.

Berberine (BBR), also known as berberine hydrochloride, was isolated from the rhizomes of the Coptis chinensis. Studies have reported that BBR plays an important role in glycolipid metabolism, including insulin (IR). The targets, and molecular mechanisms of BBR against hyperlipid-induced IR is worthy to be further studied. The related targets of BBR were identified via Pharmmapper database and relevant targets of diabetes were obtained through GeneCards and Online Mendelian Inheritance in Man (OMIM) database. The common targets were employed with the STRING database and visualized with the protein-protein interactions (PPI) network. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was performed to explore the biological progress and pathways. In vitro, human hepatocellular carcinomas (HepG2) cell was used as experimental cell line, and an insulin resistant HepG2 cell model (IR-HepG2) was constructed using free fatty acid induction. After intervention with BBR, glucose consumption and uptake in HepG2 cells were observed. Molecular docking was used to test the interaction between BBR and key targets, and real-time fluorescence quantitative PCR was used to detect the regulatory effect of BBR on related targets. 262 overlapped targets were extracted from BBR and diabetes. In the KEGG enrichment analysis, the peroxisome proliferator activated receptor (PPAR) signaling pathway was included. In vitro experiments, BBR can significantly increase sugar consumption and uptake in IR HepG2 cells, while PPAR inhibitors can weaken the effect of BBR on IR-HepG2. The PPAR signaling pathway is one of the important pathways for BBR to improve high-fat-induced insulin resistance in HepG2 cells.

Inhibiting Triggering Receptor Expressed on Myeloid Cells-1 signaling to ameliorate skin fibrosis.

Systemic sclerosis (SSc) is characterized by immune system failure, vascular insult, autoimmunity, and tissue fibrosis. Transforming growth factor-beta (TGF-β) is a crucial mediator of persistent myofibroblast activation and aberrant extracellular matrix production in SSc. The factors responsible for this are unknown. By amplifying pattern recognition receptor signaling, Triggering Receptor Expressed on Myeloid Cells 1 (TREM-1) is implicated in multiple inflammatory conditions. In this study, we used novel ligand-independent TREM-1 inhibitors in order to investigate the pathogenic role of TREM-1 in SSc, using preclinical models of fibrosis, and explanted SSc skin fibroblasts. Selective pharmacological TREM-1 blockade prevented and reversed skin fibrosis induced by bleomycin in mice and mitigated constitutive collagen synthesis and myofibroblast features in SSc fibroblasts in vitro. Our results implicate aberrantly activated TREM-1 signaling in SSc pathogenesis, identify a unique approach to TREM-1 blockade, and suggest a potential therapeutic benefit for TREM-1 inhibition.

Unveiling the critical role of androgen receptor signaling in avian sexual development

Gonadal hormone activities mediated by androgen and estrogen receptors, along with cell-autonomous mechanisms arising from the absence of sex-chromosome dosage compensation, are key factors in avian sexual development. In this study, we generate androgen receptor (AR) knockout chickens (AR−/−) to explore the role of androgen signaling in avian sexual development. Despite developing sex-typical gonads and gonadal hormone production, AR−/− males and females are infertile. While few somatic sex-specific traits persist (body size, spurs, and tail feathers), crucial sexual attributes such as comb, wattles and sexual behaviors remain underdeveloped in both sexes. Testosterone treatment of young AR−/− males fails to induce crow behavior, comb development, or regression of the bursa of Fabricius, which are testosterone-dependent phenotypes. These findings highlight the significance of androgen receptor mechanisms in fertility and sex-specific traits in chickens, challenging the concept of a default sex in birds and emphasizing the dominance of androgen signaling in avian sexual development.

Analysis of Differential Alternative Splicing in Largemouth Bass After High Temperature Exposure.

Temperature is one of the critical factors affecting the physiological functions of fish. With ongoing global warming, changes in water temperature have a profound impact on fish species. Alternative splicing, being a significant mechanism for gene expression regulation, facilitates fish to adapt and thrive in dynamic and varied aquatic environments. Our study used transcriptome sequencing to analyze alternative splicing in largemouth bass gills at 34 °C for 24 h. The findings indicated an increase in both alternative splicing events and alternative splicing genes after high temperature treatment. Specifically, the comparative analysis revealed a total of 674 differential alternative splicing events and 517 differential alternative splicing genes. Enrichment analysis of differential alternative splicing genes revealed significant associations with various gene ontology (GO) terms and KEGG pathways, particularly in immune-related pathways like necroptosis, apoptosis, and the C-type lectin receptor signaling pathway. These results emphasize that some RNA splicing-related genes are involved in the response of largemouth bass to high temperatures.

D1-like dopamine receptors promote B-cell differentiation in systemic lupus erythematosus

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune disease that currently cannot be completely cured with a great health burden. Since the production of autoantibodies plays a key role in the pathogenesis of SLE, discovering the underlying immunoregulation mechanism of B cells will be helpful for developing promising immunotherapy for SLE. In recent studies, dopamine receptors (DRDs), G protein-coupled receptors that include D1-like and D2-like subtypes, are expressed on B cells and participate in various physiological processes, involving immune responses. However, the regulatory effect of DRDs on B cells has not been determined.MethodsThis study explored the expression of DRDs on B-cell subsets from SLE patients and healthy individuals. The effects of D1-like receptor on B-cell activation and differentiation were further explored using D1-like receptor agonists or antagonists. RNA-seq and bioinformatics analyses were used to identify specific molecular mechanisms involved.ResultsThe D1-like DRDs on B cells of SLE patients were highly expressed compared with those of healthy controls (HCs). D1-like receptor agonist treatment exacerbated lupus-like symptoms in pristane-induced lupus-like mice, while D1-like receptor antagonists alleviated the lupus-like phenotypes. Inhibition of D1-like receptor signals impeded B-cell differentiation, while activation of D1-like receptor signals could promote B cell differentiation. Further RNA-seq confirmed that PTGS2, a gene related to B-cell differentiation, was up-regulated once the D1-like receptor signals were activated, while BMP6 and IL-24 were up-regulated once the D1-like receptor signals were inhibited.ConclusionD1-like receptors probably promote B-cell differentiation through the PTGS2/PRDM1 pathway.

Brain-Region-Specific Differences in Protein Citrullination/Deimination in a Pre-Motor Parkinson's Disease Rat Model.

The detection of early molecular mechanisms and potential biomarkers in Parkinson's disease (PD) remains a challenge. Recent research has pointed to novel roles for post-translational citrullination/deimination caused by peptidylarginine deiminases (PADs), a family of calcium-activated enzymes, in the early stages of the disease. The current study assessed brain-region-specific citrullinated protein targets and their associated protein-protein interaction networks alongside PAD isozymes in the 6-hydroxydopamine (6-OHDA) induced rat model of pre-motor PD. Six brain regions (cortex, hippocampus, striatum, midbrain, cerebellum and olfactory bulb) were compared between controls/shams and the pre-motor PD model. For all brain regions, there was a significant difference in citrullinated protein IDs between the PD model and the controls. Citrullinated protein hits were most abundant in cortex and hippocampus, followed by cerebellum, midbrain, olfactory bulb and striatum. Citrullinome-associated pathway enrichment analysis showed correspondingly considerable differences between the six brain regions; some were overlapping for controls and PD, some were identified for the PD model only, and some were identified in control brains only. The KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways identified in PD brains only were associated with neurological, metabolic, immune and hormonal functions and included the following: "Axon guidance"; "Spinocerebellar ataxia"; "Hippo signalling pathway"; "NOD-like receptor signalling pathway"; "Phosphatidylinositol signalling system"; "Rap1 signalling pathway"; "Platelet activation"; "Yersinia infection"; "Fc gamma R-mediated phagocytosis"; "Human cytomegalovirus infection"; "Inositol phosphate metabolism"; "Thyroid hormone signalling pathway"; "Progesterone-mediated oocyte maturation"; "Oocyte meiosis"; and "Choline metabolism in cancer". Some brain-region-specific differences were furthermore observed for the five PAD isozymes (PADs 1, 2, 3, 4 and 6), with most changes in PAD 2, 3 and 4 when comparing control and PD brain regions. Our findings indicate that PAD-mediated protein citrullination plays roles in metabolic, immune, cell signalling and neurodegenerative disease-related pathways across brain regions in early pre-motor stages of PD, highlighting PADs as targets for future therapeutic avenues.

Anti-Inflammatory Potential of Costus speciosus rhizome Bioactive Phytochemicals: A Combined GC-MS and Computational Approach Targeting TLR-4 Signaling.

Plants represent a rich reservoir of bioactive compounds with established therapeutic value in diverse diseases. Notably, the Toll-like receptor-4 (TLR-4) signaling pathway plays a pivotal role in inflammation. Upon engagement with pro-inflammatory ligands like lipopolysaccharide, TLR-4 triggers downstream cascades involving nuclear factor ĸappa B and mitogen- activated protein kinases. This signaling cascade ultimately dictates the onset and progression of inflammatory diseases. Therefore, targeting TLR-4 signaling offers a promising therapeutic approach for managing inflammatory disorders. This study investigated the potential of Costus speciosus rhizome phytocompounds, a traditional medicinal plant, as novel as modulators of TLR-4 signaling, highlighting their mechanisms of action and potential clinical applications. In the present study, 18 phytocompounds isolated from the rhizome of Costus speciosus, were studied against TLR-4/AP-1 signaling, which is implicated in the inflammatory process using a computational approach. The compounds exhibited binding affinities ranging from -4.087 to -8.93 kcal/mol with the TLR-4 protein due to the formation of multiple intermolecular interactions. Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, methyl ester (compound 7) exhibited exceptional binding energy (-8.93 kcal/mol), indicating strong affinity for the TLR-4 protein. Additionally, compound 7 displayed favorable ADMET properties, suggesting promising drug development potential. Molecular dynamics simulations confirmed the stability of the compound 7-TLR4 complex, further supporting its ability to modulate TLR-4 signaling. These findings highlight the therapeutic potential of Costus speciosus phytocompounds, particularly compound 7, as potent anti-inflammatory modulators. Further research is warranted to validate their anti-inflammatory and neuroprotective effects in pre-clinical models, paving the way for their development as novel therapeutic agents for inflammatory diseases.

Unique transcriptomic profile of peripheral blood monocytes in rheumatoid arthritis-associated interstitial lung disease.

Though interstitial lung disease (ILD) contributes to excess morbidity and mortality in rheumatoid arthritis (RA), RA-ILD pathogenesis remains incompletely defined. As intermediate, non-classical and suppressed CD14+ monocytes are expanded in RA-ILD, this study sought to characterize gene expression profiles of circulating monocytes in RA-ILD. Peripheral blood mononuclear cells were collected from patients with RA without lung disease (N = 5), RA-ILD (N = 5), idiopathic pulmonary fibrosis (IPF; N = 5), and controls without lung and autoimmune disease (N = 4). RNA was extracted from CD14+ isolated monocytes and subjected to transcriptional analysis of 1365 genes. Gene enrichment and pathway analyses were performed. Unsupervised clustering grouped patients with RA-ILD together with IPF for myeloid innate genes. For fibrosis genes, patients with RA-ILD clustered independent of comparator groups. There were 103, 66, and 64 upregulated and 66, 14, and 25 downregulated genes for RA-ILD, RA, and IPF, vs controls, respectively. For RA-ILD, there was increased expression of genes involved in regulating inflammation and fibrosis (SOCS3, CECAM1, LTB4R2, CLEC7A, IRF7, PHYKPL, GBP5, RAPGEF), epigenetic modification (KDM5D, KMT2D, OGT), and macrophage activation. Top canonical pathways included macrophage differentiation-activation, IL-12, neuroinflammatory, glucocorticoid receptor, and IL-27 signalling. Circulating monocytes in RA-ILD patients demonstrate unique gene expression profiles with innate immune gene features more aligned with IPF as opposed to RA in the absence of clinical lung disease with fibrosis gene expression that was distinct from RA and IPF. These studies are important for understanding disease pathogenesis and may provide information for future therapeutic targets in RA-ILD.

Machine learning-derived peripheral blood transcriptomic biomarkers for early lung cancer diagnosis: Unveiling tumor-immune interaction mechanisms.

Lung cancer continues to be the leading cause of cancer-related mortality worldwide. Early detection and a comprehensive understanding of tumor-immune interactions are crucial for improving patient outcomes. This study aimed to develop a novel biomarker panel utilizing peripheral blood transcriptomics and machine learning algorithms for early lung cancer diagnosis, while simultaneously providing insights into tumor-immune crosstalk mechanisms. Leveraging a training cohort (GSE135304), we employed multiple machine learning algorithms to formulate a Lung Cancer Diagnostic Score (LCDS) based on peripheral blood transcriptomic features. The LCDS model's performance was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC) in multiple validation cohorts (GSE42834, GSE157086, and an in-house dataset). Peripheral blood samples were obtained from 20 lung cancer patients and 10 healthy control subjects, representing an in-house cohort recruited at the Sixth People's Hospital of Chengdu. We employed advanced bioinformatics techniques to explore tumor-immune interactions through comprehensive immune infiltration and pathway enrichment analyses. Initial screening identified 844 differentially expressed genes, which were subsequently refined to 87 genes using the Boruta feature selection algorithm. The random forest (RF) algorithm demonstrated the highest accuracy in constructing the LCDS model, yielding a mean AUC of 0.938. Lower LCDS values were significantly associated with elevated immune scores and increased CD4+ and CD8+ T-cell infiltration, indicative of enhanced antitumor-immune responses. Higher LCDS scores correlated with activation of hypoxia, peroxisome proliferator-activated receptor (PPAR), and Toll-like receptor (TLR) signaling pathways, as well as reduced DNA damage repair pathway scores. Our study presents a novel, machine learning-derived peripheral blood transcriptomic biomarker panel with potential applications in early lung cancer diagnosis. The LCDS model not only demonstrates high accuracy in distinguishing lung cancer patients from healthy individuals but also offers valuable insights into tumor-immune interactions and underlying cancer biology. This approach may facilitate early lung cancer detection and contribute to a deeper understanding of the molecular and cellular mechanisms underlying tumor-immune crosstalk. Furthermore, our findings on the relationship between LCDS and immune infiltration patterns may have implications for future research on therapeutic strategies targeting the immune system in lung cancer.

PGRN Inhibits Early B-cell Activation and IgE Production Through the IFITM3-STAT1 Signaling Pathway in Asthma.

Progranulin (PGRN) plays a critical role in bronchial asthma and the function of various immune cells. However, the mechanisms by which PGRN influences B-cell receptor (BCR) signaling and immunoglobulin E(IgE) production are not fully understood. The study aimed to elucidate the molecular mechanisms through which PGRN affects BCR signaling, B-cell differentiation, and IgE production. A PGRN knockout mouse model, along with techniques including flow cytometry, the creation of a bone marrow chimeric mouse model, total internal reflection fluorescence (TIRF), and Western blot (WB) analysis is employed, to investigate the link between PGRN and various aspects of B-cell biology. It is discovered that the absence of PGRN in mice alters peripheral B-cell subpopulations, promotes IgE class switching in a cell-intrinsic manner, and affects B-cell subpopulations. Additionally, PGRN modulates B-cell functions by regulating BCR signaling pathways, metabolic processes, and the actin cytoskeleton during early B-cell activation. Significantly, PGRN deficiency results in diminished production of NP-specific antibodies. Moreover, it is found that PGRN inhibits B-cell activation and IgE production through the PGRN-IFITM3-STAT1 signaling pathway. The findings provide new strategies for the targeted treatment of bronchial asthma, highlighting the crucial role of PGRN in B-cell signaling and IgE production.

Employing single-cell RNA sequencing coupled with an array of bioinformatics approaches to ascertain the shared genetic characteristics between osteoporosis and obesity.

This study examined the relationship between obesity (OB) and osteoporosis (OP), aiming to identify shared genetic markers and molecular mechanisms to facilitate the development of therapies that target both conditions simultaneously. Using weighted gene co-expression network analysis (WGCNA), we analyzed datasets from the Gene Expression Omnibus (GEO) database to identify co-expressed gene modules in OB and OP. These modules underwent Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and protein-protein interaction analysis to discover Hub genes. Machine learning refined the gene selection, with further validation using additional datasets. Single-cell analysis emphasized specific cell subpopulations, and enzyme-linked immunosorbent assay (ELISA), protein blotting, and cellular staining were used to investigate key genes. WGCNA revealed critical gene modules for OB and OP, identifying the Toll-like receptor (TLR) signalling pathway as a common factor. TLR2 was the most significant gene, with a pronounced expression in macrophages. Elevated TLR2 expression correlated with increased adipose accumulation, inflammation, and osteoclast differentiation, linking it to OP development. Our study underscores the pivotal role of TLR2 in connecting OP and OB. It highlights the influence of TLR2 in macrophages, driving both diseases through a pro-inflammatory mechanism. These insights propose TLR2 as a potential dual therapeutic target for treating OP and OB.

BLNK negatively regulates innate antifungal immunity through inhibiting c-Cbl-mediated macrophage migration

B cell linker protein (BLNK) is crucial for orchestrating B cell receptor-associated spleen tyrosine kinase (Syk) signaling. However, the role of BLNK in Syk-coupled C-type lectin receptor (CLR) signaling in macrophages remains unclear. Here, we delineate that CLRs govern the Syk-mediated activation of BLNK, thereby impeding macrophage migration by disrupting podosome ring formation upon stimulation with fungal β-glucans or α-mannans. Mechanistically, BLNK instigates its association with casitas B-lineage lymphoma (c-Cbl), competitively impeding the interaction between c-Cbl and Src-family kinase Fyn. This interference disrupts Fyn-mediated phosphorylation of c-Cbl and subsequent c-Cbl-associated F-actin assembly. Consequently, BLNK deficiency intensifies CLR-mediated recruitment of the c-Cbl/phosphatidylinositol 3-kinase complex to the F-actin cytoskeleton, thereby enhancing macrophage migration. Notably, mice with monocyte-specific BLNK deficiency exhibit heightened resistance to infection with Candida albicans, a prominent human fungal pathogen. This resistance is attributed to the increased infiltration of Ly6C+ macrophages into renal tissue. These findings unveil a previously unrecognized role of BLNK for the negative regulation of macrophage migration through inhibiting CLR-mediated podosome ring formation during fungal infections.