Inflammation最新文献

Ferroptosis, an iron-dependent form of cell death driven by lipid peroxidation, plays a critical role in the progression of asthma, yet its therapeutic modulation remains underexplored. Luteolin (Lut), a natural flavonoid known for its anti-inflammatory properties, presents a potential candidate for targeting ferroptosis in asthma. However, the precise mechanisms underlying its therapeutic effects are unclear. This study used a combination of bioinformatics, network pharmacology, molecular docking, and in vitro and in vivo experiments to investigate the role of luteolin in the treatment of ferroptosis in asthma. A collection of natural flavonoid compounds with high oral bioavailability and drug-like properties was assembled from the Chinese herbal medicine database. Through network pharmacology analysis, it was discovered that these flavonoids can effectively treat ferroptosis in asthma by regulating Arachidonic acid 15-lipoxygenase (ALOX15) and arachidonic acid metabolism. Further investigation through virtual docking revealed that luteolin is a key compound in the treatment of ferroptosis in asthma, targeting ALOX15. Molecular dynamics simulations demonstrated that the ALOX15-luteolin complex is stable and flexible. Cellular Thermal Shift Assay (CETSA) confirmed the thermal stability of luteolin and ALOX15, while Drug affinity response target stability (DARTS) assay showed that luteolin inhibits the proteolysis of ALOX15 by pronase. In in vitro experiments, it was observed that luteolin treatment reduced Fe²⁺ content and lipid ROS levels in a dose-dependent manner, while also downregulating ALOX15 and ACSL4 and upregulating SLC7A11 and GPX4, effectively alleviating ferroptosis induced by house dust mite (HDM) and lipopolysaccharide (LPS) in 16HBE cells. ALOX15 was specifically knocked down in 16HBE cells, and it was found that ALOX15 silencing and luteolin treatment could also inhibit ferroptosis in asthma. In vivo experiments and serum metabolomics analyses further confirmed that luteolin inhibits ferroptosis by suppressing ALOX15 expression and regulating arachidonic acid metabolism, ultimately alleviating asthma symptoms in mice. This study found that luteolin inhibited ALOX15-mediated ferroptosis in bronchial epithelial cells to alleviate asthma, highlighting the potential of luteolin as a promising therapeutic agent for asthma treatment.

Lupus nephritis (LN), a severe manifestation of systemic lupus erythematosus, involves immune complex deposition, inflammation, and kidney damage. Recent studies indicate that pyroptosis, a pro-inflammatory cell death process, drives renal injury in LN. This study intended to identify key pyroptosis-related genes in LN using datasets from the GEO database, encompassing glomerular, tubulointerstitial, and whole kidney tissues from LN patients. Identified differentially expressed genes related to pyroptosis and created a predictive model using univariate and LASSO regression analysis. LN patients were classified into subtypes through consensus clustering. Immune microenvironment characteristics and hallmark pathways were further analyzed. Using the WGCNA, key gene modules and hub genes were recognized, followed by an analysis of their clinical relevance and distribution patterns using the Nephroseq database and scRNA-seq data. Cellular experiments were conducted to validate the findings. We identified 26 differentially expressed pyroptosis-related genes in LN glomeruli and created a 10-gene model with high diagnostic accuracy (AUC: 0.968 for tubulointerstitium, 0.990 for whole kidney). Consensus clustering divided LN into two subtypes: subtype1, characterized by inflammation and immune activation, and subtype2, characterized by cellular metabolism. WGCNA highlighted the grey60 module linked to subtype1, and identified GBP2 and EIF2AK2 as hub genes. Cellular experiments showed that GBP2 and EIF2AK2 were upregulated in LPS-stimulated macrophages and glomerular endothelial cells, and their siRNA-mediated knockdown triggered a decline in pyroptosis-related marker expression, implying their possible role as therapeutic targets for modulating pyroptosis in LN. In conclusion, GBP2 and EIF2AK2 show potential as candidate molecules for targeted therapy in LN.

Glycolysis-derived lactate serves as a substrate for lysine lactylation, an epigenetic modification playing critical transcriptional regulatory roles in inflammatory diseases. Endothelial inflammation, characterized by upregulated glycolysis, initiates atherosclerosis, yet the contribution of histone lactylation remains undefined. Although narciclasine exhibits anti-inflammatory and antioxidant properties, its impact on endothelial inflammation in atherosclerosis is unknown. Connectivity Map (CMap) analysis predicted narciclasine as an inhibitor of oscillatory shear stress and TNF-α-induced endothelial inflammation. In vitro, treatment of human umbilical vein endothelial cells (HUVECs) with 20 nM narciclasine significantly suppressed ox-LDL-induced expression of VCAM1, ICAM1, SELE, and CCL2, reduced reactive oxygen species (ROS) production, and inhibited monocyte adhesion and migration. In vivo, administration of narciclasine (0.02 mg/kg) attenuated carotid artery endothelial inflammation and macrophage infiltration, consequently reducing early atherogenesis in partial carotid ligation model in ApoE^-/- mice. Mechanistically, ox-LDL upregulated GLUT1 and PFKFB3 expression, enhancing endothelial glycolysis and lactate production. Increased lactate accumulation promoted histone H3 lysine 18 lactylation (H3K18la). Both pharmacological (2-DG, DCA) suppression of lactate production or genetic (LDHA, P300 silencing) suppression reduced H3K18la levels and inhibited ox-LDL-induced endothelial inflammation. Reanalysis of public CUT&Tag data (GEO: GSE267661) and chromatin immunoprecipitation (ChIP) validation revealed ox-LDL-induced enrichment of H3K18la at key promoters of NF-κB pathway genes (TRAF2, TRAF6, RIP1, cIAP1, RELA). Narciclasine treatment suppressed GLUT1 and PFKFB3 expression, thereby reducing H3K18la enrichment and inhibiting NF-κB pathway activation. Our findings provide novel insights into the functional role of lactylation-mediated epigenetic regulation in glycolysis-driven endothelial inflammation. Collectively, this study identifies narciclasine as a potential therapeutic candidate, which mitigates endothelial inflammation and early atherosclerosis by targeting a glycolysis-H3K18la network linked to NF-κB activation.

Diabetic encephalopathy (DE), a severe complication of diabetes, is characterized by cognitive decline and neuroinflammation, in which astrocytes play a critical role. YTHDF2, an m⁶A reader protein, has been implicated in regulating inflammatory processes. This study investigated the role of astrocytic YTHDF2 in DE pathogenesis. In a mouse model of high-fat diet-induced DE, we observed significant cognitive impairment and hippocampal inflammation. Astrocyte-specific overexpression of YTHDF2 alleviated these deficits, reducing cognitive dysfunction and the levels of pro-inflammatory cytokines IL-1β and IL-6. Both in vivo and in vitro high-glucose models confirmed that YTHDF2 overexpression suppressed astrocyte activation. YTHDF2 negatively regulated SIGMAR1 expression by promoting SIGMAR1 mRNA degradation, which inhibited astrocyte activation and inflammation. Mechanismly, SRAMP, a sequence-based predictor of m⁶A modification sites, identified four high-confidence m⁶A sites (P828, P916, P938 and P979) in SIGMAR1 mRNA. Mutation of P916 m⁶A site could inhibit SIGMAR1 mRNA degradation induced by YTHDF2 overexpression. Our findings demonstrate that astrocytic YTHDF2 attenuates astrocyte activation and neuroinflammation by promoting SIGMAR1 mRNA degradation in DE progression, which may provide a novel treatment strategy for neuroinflammation and cognitive dysfunction in DE.

Acute viral myocarditis (AVM) is a leading cause of sudden cardiac death in young individuals, and currently, there are no effective targeted clinical treatments. The role and underlying mechanisms of β2-adrenergic receptors (β2-AR) in the pathogenesis of viral myocarditis remain inadequately understood. We found that β2-AR expression reduced in monocyte-derived macrophage (MoMFs). Activation of β2-AR significantly alleviated inflammatory responses, reduced fibrosis, and improved cardiac function in AVM mice. The protective effects of activating β2-AR on AVMs were mediated by reducing MoMFs infiltration into the heart, promoting M2 phenotype, decreasing the circulating Ly6C^high proinflammatory monocytes, and increasing splenic Ly6C monocyte retention. The combination of macrophage depletion with activating β2-AR did not exhibit synergistic effects on reducing cardiac pathological scores or fibrosis. Mechanistically, metabolomic and transcriptomic analyses of heart tissues from AVM mice and bone marrow-derived macrophages (BMDMs) revealed that activating β2-AR affected energy metabolism. Specifically, activating β2-AR reduced the level of intracellular reactive oxygen species and increased energy metabolism via activated the AMP-activated protein kinase (AMPK) pathway in BMDMs. Hence, activating β2-AR may protects against AVM by regulating MoMF infiltration and preventing M1 polarization through the AMPK pathway, thereby maintaining mitochondrial balance and enhancing energy metabolism.

Diabetic periodontitis (DPD) is a severe inflammatory complication characterized by accelerated destruction of periodontal tissues and dysregulated immune responses. Gingival fibroblast (GF)-macrophage interactions drive DPD progression, but the mechanisms linking hyperglycemia, mitochondrial dysfunction, and immune activation remain unclear. Single-cell sequencing analysis of diabetic gingival tissues revealed significant apoptotic activation of GFs, closely linked to mitochondrial dysregulation. Inflammation and metabolic stress disrupt mitochondrial quality-control pathways and promote the overproduction of reactive oxygen species, inducing defective mitophagy. Crucially, apoptotic GFs secrete thrombospondin-1 (THBS-1), which binds to the CD36 receptor on the surface of macrophages, triggering NF-κB-mediated M1 polarization and pro-inflammatory cytokine production. Molecular modelling demonstrated a high-affinity interaction between THBS-1 and CD36. Gene silencing of THBS-1 in GFs or CD36 in macrophages effectively inhibited these changes, confirming the specificity of this cellular crosstalk mechanism. These findings together indicate mediation of hyperglycemia-induced mitochondrial dysfunction through the promotion of GF apoptosis and subsequent THBS-1/CD36/NF-κB-signaling-dependent macrophage activation. Thus, enhanced mitophagy and modulation of the THBS-1/CD36 axis are promising therapeutic strategies to break the self-perpetuating cycle of inflammation and tissue destruction in DPD.

Talaromyces marneffei (TM) causes a deeply invasive fatal fungal disease in immunocompromised individuals that is widespread in Southeast Asia and southern China, and little is known about how this fungus can evade the human immune system. An imbalance between M1 and M2 macrophages plays a critical role in fungal clearance. However, whether regulatory T (Treg) cells mediate the immune evasion of TM by influencing the polarization direction of macrophages remains unexplored. In this study, we found that, compared with those in healthy volunteers, the number of circulating Treg cells in the peripheral blood and serum IL-10 levels were significantly increased in HIV-negative patients with talaromycosis and were positively correlated with the recurrence frequency and severity of talaromycosis. By establishing a mouse model of TM infection, we observed that persistent TM infection promoted M2 macrophage polarization and Treg differentiation in the lungs of mice. Notably, with the prolongation of the duration of TM infection, the continuous increase in both parameters was consistent. In vitro, we confirmed that TM infection promoted Treg cell activation and increased interleukin 10 (IL-10) secretion and that IL-10 activated and promoted STAT3 phosphorylation by binding to the IL-10 receptor (IL-10R), leading to increased M2 macrophage polarization and reduced iNOS production, ultimately diminishing the macrophage-mediated killing of TM. Taken together, the results of our study revealed that during TM infection, increased numbers of activated Treg cells promote macrophage polarization toward the M2 phenotype via the IL-10/IL-10R/STAT3 signaling pathway, leading to a decrease in the ability of macrophages to eliminate intracellular TM through the iNOS-mediated pathway, which causes persistent disseminated TM infection.

Diabetic kidney disease (DKD) is a prevalent complication in individuals with diabetes. Efferocytosis plays a pivotal role in chronic diseases; however, the precise mechanisms involved in DKD are still not fully understood. DKD-related datasets were obtained from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were screened. These DEGs subsequently intersected with efferocytosis-related genes (ERGs) to produce DKD efferocytosis‒related genes (DKD-ERGs). Potential hub genes were subsequently identified using protein‒protein interaction (PPI) network analysis in combination with machine learning (LASSO regression, Boruta algorithm, and random forest algorithm). Next, we employed transcriptomics, proteomics, and metabolomics analyses of DKD animal models, followed by validation with serum samples from patients with DKD. A nomogram was developed using hub genes to evaluate its predictive accuracy. Consensus clustering was utilized to categorize DKD patients and conduct immune infiltration analysis. A total of 15 DKD-related ERGs were identified. ANXA1, CASP3, IL33, and C3 were identified as potential hub genes. First, validation was performed using the GEO and Nephroseq databases. The hub genes were subsequently validated from multiple perspectives, including transcriptomics, metabolomics, and proteomics of DKD animal models, as well as serological analysis of DKD patients. A risk score model incorporating these 4 hub genes effectively predicted both the onset and progression of DKD. On the basis of these hub genes, DKD patients were classified into Cluster 1 and Cluster 2, with distinct subtypes and immune infiltration correlating with disease stages. This study reveals the potential diagnostic value of ERGs (ANXA1, CASP3, IL33, and C3) in DKD through multidimensional analysis. These genes may serve as promising biomarkers and therapeutic targets for DKD.

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have shown promising immunomodulatory properties; however, strategies to enhance their therapeutic potential remain limited. Here, we employed CRISPR activation of the gene TSG-6 in MSCs to evaluate the impact of elevated TSG-6 on EV cargo and immunomodulatory function in an in vitro macrophage model. CRISPR-mediated gene activation was confirmed by RT-qPCR, demonstrating more than an 1800 fold increase in TSG-6 mRNA compared to controls. EVs were isolated from TSG-6 overexpressing MSCs and thoroughly characterized by nanoparticle tracking analysis, transmission electron microscopy, and Western blot, confirming their typical size distribution, morphology, and surface markers. Small RNA sequencing of these EVs revealed 15 differentially expressed miRNAs relative to EVs from control MSCs. When THP-1-derived macrophages were stimulated with LPS and treated with TSG-6-overexpressing MSC-EVs (Standard dosage: 1000 particle/cell, n = 11; Alternative dosages: 500, 1000, or 2000 particles/cell, n = 6), a marked reduction in pro-inflammatory cytokine gene expression (IL-1β, CCL2, CXCL10, and TNF-α) and secreted protein levels (CCL2, TNF-α, CXCL1, and MIP-3α) was observed. Taken together, these findings demonstrate that CRISPR-based TSG-6 activation reprograms MSC-EV miRNA cargo (as well as their protein cargo, as previously shown), which can boost their anti-inflammatory effects. These findings underscore the promise of CRISPR-activation as a novel platform for boosting the bioactive properties of MSC-EVs and enhancing immunotherapeutic efficacy.