Cell Communication and Signaling最新文献

Background: Prostate cancer (PrCa) is a significant health concern, ranking as the second most common cancer in males globally. Genetic factors contribute substantially to PrCa risk, with up to 57% of the risk being attributed to genetic determinants. A major challenge in managing PrCa is the early identification of aggressive cases for targeted treatment, while avoiding unnecessary interventions in slow-progressing cases. Therefore, there is a critical need for genetic biomarkers that can distinguish between aggressive and non-aggressive PrCa cases. Previous research, including our own, has shown that germline variants in ANO7 are associated with aggressive PrCa. However, the function of ANO7 in the prostate remains unknown.

Methods: We performed RNA-sequencing (RNA-seq) on RWPE1 cells engineered to express ANO7 protein, alongside the analysis of a single-cell RNA-sequencing (scRNA-seq) dataset and RNA-seq from prostate tissues. Differential gene expression analysis and gene set enrichment analysis (GSEA) were conducted to identify key pathways. Additionally, we assessed oxidative phosphorylation (OXPHOS), glycolysis, and targeted metabolomics. Image analysis of mitochondrial morphology and lipidomics were also performed to provide further insight into the functional role of ANO7 in prostate cells.

Results: ANO7 expression resulted in the downregulation of metabolic pathways, particularly genes associated with the MYC pathway and oxidative phosphorylation (OXPHOS) in both prostate tissue and ANO7-expressing cells. Measurements of OXPHOS and glycolysis in the ANO7-expressing cells revealed a metabolic shift towards glycolysis. Targeted metabolomics showed reduced levels of the amino acid aspartate, indicating disrupted mitochondrial function in the ANO7-expressing cells. Image analysis demonstrated altered mitochondrial morphology in these cells. Additionally, ANO7 downregulated genes involved in fatty acid metabolism and induced changes in lipid composition of the cells, characterized by longer acyl chain lengths and increased unsaturation, suggesting a role for ANO7 in regulating lipid metabolism in the prostate.

Conclusions: This study provides new insights into the function of ANO7 in prostate cells, highlighting its involvement in metabolic pathways, particularly OXPHOS and lipid metabolism. The findings suggest that ANO7 may act as a key regulator of cellular lipid metabolism and mitochondrial function in the prostate, shedding light on a previously unknown aspect of ANO7's biology.

Neutrophils are the first responders among peripheral immune cells to infiltrate the central nervous system following a traumatic brain injury (TBI), triggering neuroinflammation that can exacerbate secondary tissue damage. The precise molecular controls that dictate the inflammatory behavior of neutrophils post-TBI, however, remain largely elusive. Our comprehensive analysis of the molecular landscape surrounding the trauma in TBI mice has revealed a significant alteration in the abundance of β2 integrin (ITGB2), predominantly expressed by neutrophils and closely associated with immune responses. Using the fluid percussion injury (FPI) mouse model, we investigated the therapeutic efficacy of Rovelizumab, an agent that blocks ITGB2. The treatment has demonstrated significant improvements in neurologic function in TBI mice, attenuating blood-brain barrier permeability, mitigating oxidative stress and inflammatory mediator release, and enhancing cerebral perfusion. Moreover, ITGB2 blockade has effectively limited the adherence, migration, and infiltration of neutrophils, and has impeded the formation of neutrophil extracellular traps (NETs) upon their activation. Finally, it was demonstrated that ITGB2 mediates these effects mainly through its interaction with intercellular adhesion molecule-1 (ICAM 1) of endotheliocyte. These findings collectively illuminate ITGB2 as a crucial molecular switch that governs the adverse effects of neutrophils post-TBI and could be targeted to improve clinical outcome in patients.

Synchrotron-radiation nano-X-Ray Fluorescence (XRF) is a cutting-edge technique offering high-resolution insights into the elemental composition of biological tissues, shedding light on metabolic processes and element localization within cellular structures. In the context of Idiopathic Pulmonary Fibrosis (IPF), a debilitating lung condition associated with respiratory complications and reduced life expectancy, nano-XRF presents a promising avenue for understanding the disease's intricate pathology. Our developed workflow enables the assessment of elemental composition in both human and rodent fibrotic tissues, providing insights on the interplay between cellular compartments in chronic lung diseases. Our findings demonstrate trace element accumulations associated with anthracosis, a feature observed in IPF. Notably, Zn and Ca clusters approximately 750 nm in size were identified exclusively in IPF samples. While their specific role remains unclear, their presence may be associated with disease-specific processes. Additionally, we observed Fe and S signal colocalization in 650-nm structures within some IPF cells. Fe-S complexes in mitochondria are known to be associated with increased ROS production, suggesting a potential connection to the disease pathology. In contrast, a bleomycin-induced fibrosis rodent model exhibits a different elemental phenotype with low Fe and increased S, Zn, and Ca. Overall, our workflow highlights the effectiveness of synchrotron-based nano-XRF mapping in analyzing the spatial distribution of trace elements within diseased tissue, offering valuable insights into the elemental aspects of IPF and related chronic lung diseases.

Background: Fibrosis remains a major complication in several chronic diseases, including systemic sclerosis (SSc). Plasmacytoid dendritic cells (pDCs) are innate immune cells that play a key role in the development of fibrosis in SSc patients, through still poorly defined mechanisms. Interestingly, endoplasmic reticulum (ER) stress signaling pathways are dysregulated in pDCs from patients with SSc, but their contribution to fibrosis remains unclear. Thus, this study aimed to unravel the mechanisms behind the involvement of pDCs and ER stress in fibrosis.

Methods: To address this question, we established an in vitro model designed to study the interactions between pDCs and fibroblasts. More specifically, IMR-90 fibroblasts were co-cultured with CAL-1, a pDC cell line. ER stress was then induced by the bacterial toxin SubAB. Extracellular matrix (ECM) production was assessed using immunoblotting, qPCR and confocal microscopy. The importance of cell-to-cell contact was investigated using conditioned media (CM) and transwell assays.

Results: Direct contact of CAL-1 and IMR-90 cells under ER stress conditions led to increased expression of fibronectin and alpha-smooth muscle actin (α-SMA). This effect required expression of the ER stress signaling sensor protein kinase R-like ER kinase (PERK) in pDCs and was observed only upon direct contact between both cell types.

Conclusions: Overall, our data suggest that ER stress induction in pDCs promotes fibroblast activation, which may contribute to the development of fibrosis in SSc.

Fungi are notorious for causing diseases in plants and domestic animals. ABC transporters play pivotal roles in multidrug resistance in fungi, with some ABC proteins indispensable for the pathogenicity of plant fungal pathogens. However, the roles of ABC proteins in animal pathogenic fungi, and the functional connections between ABC homologues in plant and animal pathogenic fungi are largely obscure. Here, we identified a new ABCG-1 gene, MoCDR1, in rice-blast fungus Magnaporthe oryzae. MoCDR1 disruption caused hypersensitivity to multidrugs, and impaired conidiation, appressorium formation, and pathogenicity. Subsequently, we systematically retrieved ABC proteins in animal pathogenic fungus Trichophyton mentagrophytes and identified TmCdr1, a homologue to MoCdr1. TmCDR1 effectively rescued the drug sensitivity and virulence of ΔMocdr1 and mediated the drug resistance and animal skin infection in T. mentagrophytes. Moreover, MoCDR1 also rescued the defects in drug sensitivity and virulence of ΔTmcdr1. MoCdr1 and TmCdr1 are conserved in structures and functions, and both involved in drug resistance and pathogenicity by analogously regulating gene expression levels related to transporter activity, MAPK signaling pathway, and metabolic processes. Altogether, our results represent the first comprehensive characterization of ABC genes in T. mentagrophytes, establishing a functional correlation between homologous ABC genes in plant and animal pathogenic fungi.

Background: Neuronal intranuclear inclusion disease (NIID) is genetically linked to CGG repeat expansion in the 5'-untranslated region of the NOTCH2NLC gene, with nascent polyglycine-containing protein (uN2CpolyG) identified as a primary pathogenic factor. Emerging clinical evidence suggests that inflammation contributes to NIID pathogenesis, yet the underlying molecular mechanisms remain elusive. This study aimed to elucidate the molecular interaction between uN2CpolyG and the NF-κB-NLRP3 pathway.

Methods: Single-cell RNA sequencing was conducted on the skin tissues of NIID patients to assess changes in the expression of genes involved in inflammatory pathways. Cell models (HEK-293T and U87-MG) transfected with CGG_9/69/100 expansion vectors were used to investigate alterations in the NF-κB-NLRP3-autophagy pathway. Additionally, the therapeutic potential of NF-κB activators was evaluated in a Drosophila model with a CGG expansion knock-in.

Results: Single-cell sequencing revealed a significant reduction in the expression of NFKBIA, encoding NF-κB inhibitor alpha (IkBa), which facilitates the nuclear translocation of p65, a key NF-κB component. uN2CpolyG directly interacted with and sequestered p65 in nuclear inclusions, leading to reduced phosphorylated p65 (p-p65) levels. This sequestration significantly downregulated the NF-κB-NLRP3 pathway, impairing autophagy, as indicated by decreased LC3II/LC3I ratios. Treatment of CGG₁₀₀ cells with lipopolysaccharide (LPS) significantly increased p-p65, NLRP3, and LC3II/LC3I levels while reducing insoluble uN2CpolyG levels and intranuclear inclusions. In the Drosophila knock-in model, LPS significantly reduced the number of intranuclear inclusions and improved phenotypic manifestations.

Conclusions: This study revealed that uN2CpolyG directly interacts with and sequesters p65, thereby inhibiting the NF-κB-NLRP3 pathway and impairing autophagy. This mechanism highlights a novel therapeutic target for NIID and provides potentially broader insights into similar mechanisms in other neurodegenerative diseases characterized by misfolded protein aggregates.

Background: Vimentin is a type III intermediate filament protein that plays an important role in cytoskeletal mechanics. It is now known that vimentin also has distinct functions outside the cell. Recent studies show the controlled release of vimentin into the extracellular environment, where it functions as a signaling molecule. Such observations are expanding our current knowledge of vimentin as a structural cellular component towards additional roles as an active participant in cell signaling.

Methods: Our study investigates the immunological roles of extracellular vimentin (eVim) and its citrullinated form (CitVim) as a damage-associated molecular pattern (DAMP) engaging the Toll-like receptor 4 (TLR4) of human neutrophils. We used in vitro assays to study neutrophil migration through endothelial cell monolayers and activation markers such as NADPH oxidase subunit 2 (NOX2/gp91phox). The comparison of eVim with CitVim and its effect on human neutrophils was extended to the induction of extracellular traps (NETs) and phagocytosis of pathogens.

Results: Both eVim and CitVim interact with and trigger TLR4, leading to increased neutrophil migration and adhesion. CitVim stimulated the enhanced migratory ability of neutrophils, activation of NF-κB, and induction of NET formation mainly mediated through reactive oxygen species (ROS)-dependent and TLR4-dependent pathways. In contrast, neutrophils exposed to non-citrullinated vimentin exhibited higher efficiency in favoring pathogen phagocytosis, such as Escherichia coli and Candida albicans, compared to CitVim.

Conclusions: Our study identifies new functions of eVim in its native and modified forms as an extracellular matrix DAMP and highlights its importance in the modulation of immune system functions. The differential effects of eVim and CitVim on neutrophil functions highlight their potential as new molecular targets for therapeutic strategies aimed at regulation of neutrophil activity in different pathological conditions. This, in turn, opens new windows of therapeutic intervention in inflammatory and immunological diseases characterized by immune system dysfunction, in which eVim and CitVim play a key role.

Background: Acute pneumonia is a kind of widespread inflammatory pathological process. Dihydrocaffeic acid (DA), metabolite of chlorogenic acid, possesses potent pharmacologic activity for the therapy of a wide range of disorders and various biological properties, such as anti-inflammation. Nevertheless, the specific protein targets and potential molecular mechanisms of DA in acute pneumonia are still poorly understood.

Purpose: To investigate the anti-inflammation effects of DA and its target and its specific mechanisms.

Methods: Here, we conducted lipopolysaccharides (LPS)-induced acute pneumonia model mice. Besides, the activity-based protein profiling (ABPP) was performed to explore the potential targets of DA. Furthermore, cellular thermal shift assay (CETSA) and pulldown-western blot assays were used to validate the conclusion.

Results: In this study, we indicated that DA alleviated acute pneumonia in mice and displayed excellent anti-inflammatory efficacy in vivo and in vitro. Besides, we discovered DA binds directly to transaldolase 1(TALDO1) and influenced its enzymatic activity, and identified the specific cysteine sites Cys250. Also we demonstrated that DA reveals anti-inflammation effect through TALDO1 mediated PERK-IκBα-NF-κB pathway in RAW 264.7 cells.

Conclusion: This study provide support for the potential advancement of DA for use as a therapeutic agent for the treatment of acute pneumonia and inflammation-associated diseases.

Immune response gene 1 (IRG1) is highly expressed in mitochondria of macrophages in a pro-inflammatory state. IRG1 and its metabolites play important roles in infection, immune-related diseases and tumor progression by exerting resistance of pathogens, attenuating inflammation and producing antioxidant substances through various pathways and mechanisms. IRG1 deficiency aggravates liver injury. Efferocytosis is a vital mechanism for preventing the progression of inflammatory tissue damage. However, the mechanism by how IRG1/itaconate regulates efferocytosis in autoimmune hepatitis has yet to be fully understood. Therefore, we explored the influence of IRG1-/- on efferocytosis and its effects on regulating the nuclear factor erythroid 2-associated factor 2 (Nrf2)-T-cell immunoglobulin domain and mucin domain 4 (TIM4) pathway and autoimmune liver injury. An autoimmune hepatitis model was established by injecting Con A into wild-type and IRG1-/- mice via the tail vein. Liver injury and inflammatory response were assessed. The efferocytosis role of IRG1-/- macrophages and its potential regulatory mechanisms were also analysed. Exogenous 4-octyl itaconate (OI) supplementation promoted the expression of Nrf2 and TIM4 and restored IRG1-/- bone marrow-derived macrophage (BMDM) efferocytosis, whereas inhibition of Nrf2 mediated by ML385 led to impaired efferocytosis of BMDMs, decreased expression of TIM4, and aggravated liver inflammation injury. Additionally, after supplementing Nrf2-/- BMDMs with exogenous OI, we evaluated the changes in its efferocytosis effect, efferocytosis did not change, and the protective effect of OI disappeared. However, when TIM4 was blocked, the efferocytotic effect of BMDMs was attenuated, inflammatory liver injury and oxidative stress were aggravated. OI promoted the transformation of macrophages into M2 macrophages, and this was inhibited when TIM4 was blocked. To our best understanding, this is the initial exploration to show that TIM4, a downstream molecule of the IRG1/itaconate-Nrf2 pathway, regulates macrophage efferocytosis. These findings suggest a new mechanism and potential treatment for promoting the resolution of inflammation and efferocytosis in autoimmune hepatitis.

Animal models are crucial for elucidating the pathological mechanisms underlying Parkinson's disease (PD). Unfortunately, most of transgenic mouse models fail to manifest pathological changes observed in PD patients, pending the advancement of PD research. However, the mechanism underlying this discrepancy remains elusive. Here, we provide compelling evidence that the compensatory expression of synaptotagmin-11 (Syt11) plays a key role in concealing PD-associated phenotypes in parkin knockout (KO) mouse models. Unlike the normal dopamine (DA) release and motor behaviors observed in parkin KO mice, parkin knockdown (KD) in the substantia nigra pars compacta (SNpc) in adult mice led to both the impaired DA release and the pronounced motor deficits. Interestingly, Syt11, a well-established parkin substrate involved in PD, was specifically upregulated in parkin KD mice and in parkin KO mice during the suckling stage, but not in adult parkin KO mice. Importantly, the overexpression of Syt11 alone is capable of inducing PD-like motor and non-motor impairments, as well as the impaired DA release and reuptake, which is essential for parkin-associated pathogenesis of PD. Therefore, this work not only elucidate a compensatory mechanism that accounts for the absence of overt PD phenotypes in parkin KO mice, but also contribute to the comprehensive understanding of the progression of PD, opening new avenues for the therapeutic treatment of PD.