Inflammation Research最新文献

Background: The NLRP3 inflammasome is a critical mediator of innate immune responses and inflammatory diseases, and its activation is tightly regulated by post-translational modifications such as ubiquitination. While several E3 ligases have been shown to modulate NLRP3 activity, deubiquitinases are increasingly recognized as key regulators that control NLRP3 stability and activation. However, the identification of additional deubiquitinases and pharmacological inhibitors remains essential for a comprehensive understanding of NLRP3 inflammasome regulation. This study investigated the role of the deubiquitinase USP2 in NLRP3 inflammasome activation and evaluated the therapeutic potential of its inhibitor ML364 in inflammasome-driven inflammatory diseases.

Materials and methods: Murine macrophage cell lines (J774A.1), HEK293 cells, and bone marrow-derived macrophages (BMDMs) were used to assess inflammasome activation through genetic knockdown, overexpression, and pharmacological inhibition of USP2. Protein interactions, ubiquitination status, ASC speck formation, caspase-1 activation, and IL-1β secretion were evaluated using immunoprecipitation, immunoblotting, microscopy, and ELISA. In vivo efficacy of the USP2 inhibitor ML364 was examined in mouse models of monosodium urate (MSU)-induced peritonitis and dextran sulfate sodium (DSS)-induced colitis by assessing inflammatory cell recruitment, cytokine production, disease activity, and histopathology.

Results: USP2 was required for optimal NLRP3 inflammasome activation, as its knockdown or pharmacological inhibition significantly reduced caspase-1 activation, IL-1β release, and pyroptotic responses. Mechanistically, USP2 directly interacted with the NACHT domain of NLRP3 and promoted its stability by removing ubiquitin chains, whereas a catalytically inactive USP2 mutant failed to support inflammasome activation. USP2 deficiency increased NLRP3 ubiquitination and reduced protein abundance in macrophages. Importantly, ML364 effectively suppressed NLRP3 inflammasome activation in vitro and alleviated inflammatory responses in vivo, reducing neutrophil recruitment, IL-1β production, and tissue injury in MSU-induced peritonitis and DSS-induced colitis models.

Conclusion: USP2 acts as a critical deubiquitinase that promotes NLRP3 inflammasome activation by stabilizing NLRP3 through deubiquitination of its NACHT domain. Pharmacological inhibition of USP2 with ML364 effectively suppresses inflammasome activation and ameliorates inflammatory pathology in vivo. These findings identify USP2 as an important regulator of NLRP3 signaling and highlight ML364 as a potential therapeutic strategy for NLRP3 inflammasome-associated diseases.

Objective: This study investigates the therapeutic potential of interleukin-22 (IL-22) in polycystic ovary syndrome (PCOS) and its mechanisms.

Methods: A dehydroepiandrosterone (DHEA)-induced PCOS mouse model and testosterone-treated human KGN granulosa cells were utilized. Mice received IL-22 (50-100 µg/kg) or Diane-35 for 3 weeks.

Results: IL-22 administration restored estrous cyclicity, reduced ovarian cysts, and normalized serum testosterone and insulin levels in DHEA or letrozole-induced PCOS mice. DHEA induction led to mitochondrial damage in granulosa cells (GCs), evidenced by impaired mitochondrial membrane potential, mtDNA copy number depletion, and ROS accumulation, alongside lipid metabolic dysregulation. These detrimental effects were ameliorated by IL-22. Bioinformatics analysis of PCOS patient data revealed significant enrichment in lipid metabolism pathways. A high-fat diet abolished IL-22's PCOS-restoring effects, underscoring lipid metabolism as a key mechanism. We identified 19 lipid metabolism-related genes, with ETS1 being the most significantly regulated. IL-22 inhibited ETS1 expression induced by DHEA through the activation of STAT3 dependent on the IL-22R1, and Chromatin Immunoprecipitation (ChIP)-PCR confirmed STAT3 binding to the ETS1 promoter.

Conclusion: Our findings highlight IL-22 as a promising therapeutic candidate for PCOS, acting through the IL-22R1/STAT3/ETS1 pathway to ameliorate mitochondrial dysfunction and lipid metabolic reprogramming in GCs. This study bridges immune signaling with metabolic pathology in PCOS, offering novel avenues for targeted intervention.

Objective: Periodontal bone regeneration remains a major challenge in in the treatment of periodontitis. This study we aimed to investigate whether there are CD169⁺ macrophages in periodontal tissues and the functions of these cells in the progressive and resolving phases of periodontitis.

Methods: Immunofluorescence staining was performed to localize CD169⁺ macrophages in human and murine periodontal tissues. Subsequently, CD169⁺ macrophages from mature bone marrow-derived macrophages (BMDMs) were isolated. To characterize their functional properties, we assessed the phagocytic capacity of CD169⁺ macrophages in vitro. Furthermore, CD169⁺ macrophages were co-cultured to evaluate their osteogenic-promoting effects by qPCR, alkaline phosphatase (ALP) staining, and alizarin red staining (ARS). For in vivo validation, ligature-induced periodontitis (LIP) mice were established and local bacterial inoculated to investigate phagocytic function of CD169⁺ macrophages. Anti-interferon-alpha/beta receptor (Anti-IFNAR1) was injected locally to inhibit the signaling of IFN Is. Bone repair was assessed using micro-computed tomography (micro-CT) and histological staining.

Results: CD169 was primarily expressed on macrophages in periodontal tissues. In vitro CD169⁺ macrophages were positively induced by IFN Is. CD169⁺ macrophages exhibited robust phagocytic activity in clearing Porphyromonas gingivalis (P. gingivalis). Moreover, CD169⁺ macrophages promoted the osteogenic differentiation of BMSCs through the secretion of interleukin 10 (IL10), as evidenced by upregulated expression of osteogenesis-related genes (including Alpl, Sp7, Ibsp and Bglap), enhanced activity of ALP, and increased formation of mineralized nodules. In vivo results further demonstrated that CD169⁺ macrophages exhibited a high phagocytic capacity against P. gingivalis compared. During the resolving phase of periodontitis, a decrease in the number of CD169⁺ macrophages resulting from Anti-IFNAR1 application not only impaired alveolar bone repair, but also reduced expression of IL10 and osteogenesis-related proteins, such as OSX(Sp7) and OCN(Bglap).

Conclusions: CD169⁺ macrophages play a critical role in periodontitis by clearing of P. gingivalis during the progressive phase of periodontitis, and promoting bone repair via the secretion of IL10 during the resolving phase.

Background: Cochlin, encoded by the COCH gene, mediates innate immunity against bacterial infections by segregating pathogens and recruiting immune cells through its N-terminal LCCL domain. This domain is cleaved and secreted to attract macrophages and neutrophils, but its core motif has remained unclear.

Methods: We designed and synthesized a shortened core peptide of the LCCL domain (cLCCL; 62 amino acids) preserving the conserved structural motif. Structural stability was predicted by in silico modeling. The immunomodulatory effects of LCCL and cLCCL were evaluated in RAW264.7 macrophage cells using bulk RNA sequencing, quantitative PCR, Western blotting, flow cytometry, and immunocytochemistry.

Results: RNA sequencing in RAW264.7 cells showed that both LCCL and synthetic cLCCL peptides induced M1 polarization, with upregulation of TICAM2, CD40, and CD86. Flow cytometry demonstrated a significant increase in CD40(+)/CD86(+) M1-polarized macrophages following LCCL or cLCCL treatment, with comparable effects between the full-length and core peptides.

Conclusion: The identified cLCCL appears to promote pro-inflammatory macrophage polarization, activate pro-inflammatory innate immune pathways, and warrants further evaluation in mechanistic and in vivo studies.

Background: Ulcerative colitis (UC) is a chronic inflammatory disease characterized by mucosal immune activation and epithelial barrier breakdown. The pathogenic mechanisms underlying UC remain incompletely understood, and identifying key molecular drivers of disease onset and progression may provide new therapeutic opportunities.

Methods: A total of 1,446 samples were integrated to identify key genes through machine learning and SHAP analysis. Immune infiltration, cytokine activity, barrier gene expression, and clinical outcomes were analyzed. Functional and mechanistic validations were further performed in lipopolysaccharide (LPS)-stimulated HT29 cells.

Results: FBXO6, COL1A2, and NPY emerged as robust diagnostic biomarkers that stratify UC patients into molecular subgroups with distinct inflammatory states and therapeutic responses. High FBXO6 expression correlated with macrophage-driven inflammation, barrier disruption, and reduced responsiveness to biologics. Mechanistically, FBXO6 directly bound SLC3A2 and induced its degradation through K48-linked ubiquitination, thereby promoting ferroptosis and amplifying mucosal inflammation.

Conclusion: A previously unrecognized ubiquitin-mediated FBXO6-SLC3A2 axis was identified as a critical driver of ferroptosis and epithelial barrier disruption in UC. Targeting FBXO6 to preserve SLC3A2 stability is proposed as a potential therapeutic strategy to restore epithelial integrity and improve treatment responsiveness in patients with UC.

Background: The complement system critically mediates systemic lupus erythematosus (SLE) pathogenesis through dual mechanisms: promoting inflammatory organ damage while regulating the initiation of immune tolerance. Among its three activation pathways (classical, alternative, and lectin), the lectin pathway is the most recently characterized.

Findings: The lectin pathway engages pattern-recognition molecules (PRMs: mannose-binding lectin [MBL], collectins, ficolins) and mannose-binding lectin-associated serine proteases (MASPs). These components orchestrate unique biological functions beyond canonical complement activation, including self-antigen clearance, B/T-cell tolerance modulation, and interferon-α production. PRM/MASP genetic variants (particularly loss-of-function genotypes) predispose to SLE and associate with organ-specific damage phenotypes. PRMs detect damage-associated molecular patterns on apoptotic cells, initiating complement activation. Resulting fragments (C3a, C5a) and membrane attack complexes directly drive tissue injury. Clinically, circulating PRM/MASP levels and tissue deposition patterns reflect disease activity and organ involvement. Although MASP-2- and C5-targeting monoclonal antibodies demonstrate therapeutic potential in trials, most lectin pathway interventions remain preclinical.

Conclusions: This review integrates clinical correlations, mechanistic advances in both complement-dependent and complement-independent functions, and emerging SLE therapeutics targeting the lectin pathway.

Background: Thrombosis was recognized as a significant cause of morbidity and mortality for prostate cancer (PCa). The potential mechanisms underlying the effect of thrombosis on PCa remain elusive.

Methods: Retrospective analysis of dual-center clinical data identified thrombosis-PCa correlations. Bioinformatics integration of TCGA-PRAD transcriptomics and thrombosis-related genes enabled construction of a prognostic signature, validated externally. Functional, immune, and drug sensitivity analyses were performed. Experimental validation included IHC, qPCR, IF, in vitro functional assays, and in vivo models.

Results: Elevated thrombosis risk strongly correlated with PCa aggressiveness and adverse clinical features. A five-gene risk model stratified PCa patients into distinct survival groups (low-risk: superior outcomes), validated by ROC/Cox analyses as an independent prognostic tool. Findings from functional enrichment, alongside evaluations of immune cell infiltration, immunotherapy responsiveness, and drug sensitivity, reinforced the capacity to accurately forecast the clinical efficacy of precision therapies, as validated by clinical relevance analysis and nomogram development. Immunohistochemistry and qPCR of signature genes revealed marked differences between PCa and adjacent tissues. Importantly, experimental knockdown of VAV2 in 22RV1 cells downregulated prothrombotic inflammatory factors (CXCL8, IL-6, and VEGF). Conditioned media from VAV2-knockdown cells markedly inhibited tube formation in HUVECs and suppressed NETs formation. In vivo, mice administered with conditioned media from VAV2-deficient cells exhibited prolonged PT and APTT, and reduced fibrinogen levels, indicating attenuated coagulation potential.

Conclusion: We successfully developed and validated an innovative and robust five-gene signature, seamlessly integrating clinical prognostic parameters for the precise prediction of PCa patients outcomes. This dissertation offers an in-depth exploration of thrombosis, elucidating potential biological mechanisms underpinning therapeutic strategies related to tumor immunity in PCa.

Background: Sepsis therapy faces a critical paradox: Gasdermin D (GSDMD)-mediated neutrophil extracellular traps (NETs) exert protective host defense early but drive tissue injury late. Defining the temporal dynamics of intervening in this axis is central to overcoming therapeutic limitations.

Methods: In a cecal ligation and puncture (CLP) model recapitulating human sepsis progression, disulfiram (DSF, 80 mg/kg) or vehicle was administered intraperitoneally at 0 h, 4 h, or 8 h postoperatively. A comprehensive multidimensional analysis assessed survival, bacterial burden (lung/blood/peritoneum), cytokines (TNF-α/IL-6/IL-1β), lung injury (histopathology/wet-dry ratio/Evans Blue extravasation), GSDMD activation, NET formation (Sytox-green/CitH3-MPO), and neutrophil function (LY6G⁺ infiltration/viability).

Results: Immediate DSF (0 h) proved detrimental, exacerbating bacterial dissemination (lung↑, P = 0.0036; blood↑, P = 0.0488), hyperinflammation (TNF-α↑, P = 0.0165; IL-6↑, P = 0.0140), and shortening survival (P = 0.0417). Conversely, delayed DSF (8 h) yielded significant benefits, reducing bacterial load (lung↓, P = 0.0002; blood↓, P = 0.0309), suppressing cytokines (TNF-α↓, P = 0.0121; IL-6↓, P = 0.0022), and extending survival (P < 0.0001). Mechanistically, while DSF consistently inhibited GSDMD cleavage and NETs, only delayed intervention attenuated NET-driven microthrombosis, reduced LY6G⁺ infiltration (P = 0.0112), and enhanced neutrophil viability (P = 0.0007).

Conclusion: Targeting the GSDMD-NETs axis is fundamentally timing-dependent. Immediate inhibition disrupts essential host defenses, whereas delayed treatment (8 h post-CLP) preserves bacterial clearance, reduces lung injury, and improves survival. By establishing a therapeutic window, our study provides the first systematic evidence that the success of disulfiram in sepsis depends on when it is administered, offering a clinically actionable framework to guide future biomarker-driven trials and bedside decision-making in critical care.