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摘要： The function of islet macrophages is poorly understood. They promote glucose-stimulated insulin secretion (GSIS) in lean mice, however, the underlying mechanism has remained unclear. We show that activation of the free fatty acid receptor FFAR4 on islet macrophages leads to interleukin-6 (IL-6) release and that IL-6 promotes beta-cell function. This mechanism is required for GSIS in lean male mice, but does not function anymore in islets from people with obesity and obese type 2 diabetic male mice. In islets from obese mice, FFAR4 downstream signaling in macrophages is strongly reduced, resulting in impaired FFAR4-mediated IL-6 release. However, IL-6 treatment can still improve GSIS in islets from people with obesity and obese type 2 diabetic mice. These data show that a defect in FFAR4-mediated macrophage activation contributes to reduced GSIS in type 2 diabetes and suggest that reactivating islet macrophage FFAR4 and promoting or mimicking IL-6 release from islet macrophages improves GSIS in type 2 diabetes.

摘要： Interleukin-1 (IL-1)/IL-1 receptor family consists of activators and inhibitors which play a key role in inflammation, emergency myelopoiesis, and myeloid cell activation. The latter includes the IL-1R2 decoy receptor. To investigate the expression and significance of IL-1R2 in sepsis, we conducted high-dimensional flow cytometry of circulating cells from patients stratified according to the Sequential Sepsis-Related Organ Failure Assessment (SOFA) score. Here we report that the IL-1 decoy receptor is selectively upregulated on the plasma membrane of leukocytes and, in particular, monocytes from septic patients, and downregulated in septic shock. Flow cytometry combined with transcriptomic analysis of publicly available datasets indicated that IL-1R2 is associated with the differentiation of monocytes to a population of circulating monocytic cells with macrophage features (Mono/M phi). In vitro stimulation of monocytes from healthy donors with Colony Stimulating Factors (CSFs), in particular GM-CSF and Lipopolysaccharides (LPS), induced IL-1R2+ Mono/M phi, which recapitulated the characteristics of sepsis-associated monocytic cells, including low expression of HLA-DR, high levels of macrophage markers such as MS4A4A and CD63, immune checkpoints, immunosuppressive molecules and selected scavenger receptors. Membrane-associated IL-1R2 and MS4A4A correlated with immunological markers, cytokine storm, and clinical parameters (e.g., SOFA score, creatinine, survival), reflecting the infection severity in hospitalized ***, in sepsis IL-1R2 is expressed in a subset of circulating monocytes co-expressing mature macrophage and immune dysfunction features with clinical significance.

关键词： TG2   Serotonin   TNF   RIPK1  

摘要： The receptor interacting protein kinase 3 (RIPK3) is the main player in the activation of necroptosis, a pro-inflammatory regulated cell death modality induced by many different stimuli. RIPK3 is epigenetically regulated by DNA methylation and can be expressed when its promoter is associated with H3K4me3 histone. In this study, we show that Transglutaminase 2 protein (TG2) is necessary to induce necroptosis pathway allowing the expression of Ripk3 gene. Indeed, cells lacking TG2 show a strong downregulation of Ripk3 gene and are resistant to necroptotic stimuli. TG2 is known to promote the serotonylation of H3K4me3 histone (H3K4me3Q5ser) regulating in this way the target gene expression. Interestingly, we find that TG2 interacts with both histones H3K4me3 and H3K4me3Q5ser and these post-translational modifications are associated with the Ripk3 promoter only in presence of TG2. In addition, the absence of the H3K4me3Q5ser, in cells lacking TG2, is correlated with Ripk3 gene methylation. Altogether, these results indicate that RIPK3 expression requires TG2 mediated serotonylation of H3K4me3 to prevent Ripk3 promoter methylation, thus favouring its expression and necroptosis *** AbstractTG2 serotonylates histone H3K4me3, associated to Ripk3 promoter, and stabilizes it preventing DNA methylation of Ripk3 promoter. Therefore, TG2 favours the expression of Ripk3 making cells susceptible to necroptosis. In the absence of TG2, serotonylation on histone H3, associated to Ripk3 promoter, doesn't occur favoring its demethylation. Consequently, Ripk3 promoter is methylated, blocking the activation of necroptosis

关键词： calcineurin inhibitors   calcineurin isoforms   NKCC2 phosphorylation   TNF  

摘要： We previously demonstrated that tumor necrosis factor-alpha (TNF) inhibits Na+-K+-2Cl(-) cotransporter (NKCC2) phosphorylation in the thick ascending limb (TAL);however, the underlying mechanism remains unclear. We tested the hypothesis that the induction of calcineurin (CN) activity and the expression of CN isoforms contribute to the mechanism by which TNF inhibits phospho-NKCC2 (pNKCC2) expression. CN activity increased by approximately twofold in primary cultures of medullary (m)TAL cells challenged with mouse recombinant TNF. In contrast, silencing TNF production in mTAL cells using lentivirus U6-TNF-ex4 reduced CN activity. pNKCC2 expression decreased in mTAL cells challenged with TNF, whereas inhibition of CN activity with cyclosporine A (CsA) increased pNKCC2 expression. Although mTAL cells express both the calcineurin A subunit (CNA) alpha and beta isoforms, only CNA beta isoform mRNA increased after mTAL cells were challenged with TNF. In vivo, both TNF and CNA beta expression increased in outer medulla (OM) from mice given 1% NaCl in the drinking water for 7 days and intrarenal lentivirus silencing of TNF selectively reduced expression of CNA beta. Intrarenal injection of a lentivirus that specifically silenced CNA beta (U6-CNA beta-ex6) increased pNKCC2 expression and attenuated the inhibitory effects of TNF on pNKCC2 expression in freshly isolated TAL tubules. Collectively, the study is the first to demonstrate that TNF increases CN activity and specifically induces beta-isoform expression in the kidney. Since NKCC2 is a known target of the CNA beta isoform, these findings suggest that a CN-dependent signaling pathway involving this isoform contributes to the mechanism by which TNF inhibits pNKCC2 expression.

关键词： anastomotic leakage   rectal cancer   IL-17   intraoperative hypothermia   risk factor  

摘要： Objective: In this prospective observational cohort study, we aim to investigate the risk factors for early postoperative anastomotic leakage (AL) in patients undergoing rectal cancer resection. Methods:This study included 459 patients with rectal cancer who underwent treatment at our hospital from January 2021 to October 2022. All patients were hospitalized for 1 week postoperatively and observed for the occurrence of AL. Fasting venous blood samples (5 mL) were collected from all cases 1 day before surgery and 1, 2, and 3 days after surgery, and serum levels of interleukins (IL)-17, IL-6, IL-1 beta, tumor necrosis factor-alpha, and C-reactive protein (CRP) were determined using enzyme-linked immunosorbent assay. Demographic, clinical data, intraoperative hypothermia, and nutritional indicators were collected for all patients. Statistical analysis was performed using SPSS 25.0 software. Results: AL patients had significantly lower hemoglobin, albumin (ALB) levels, and a higher proportion of intraoperative hypothermia compared to patients in the non-AL group (P < .05). On the first, second, and third days after surgery, patients in the AL group had significantly higher levels of serum CRP, IL-1 beta, and IL-17 compared to the non-AL group. Pearson's correlation analysis showed a positive correlation between serum IL-17 levels and CRP levels. Serum IL-17 had the highest predictive value for early AL, with an area under the curve (AUC) of 0.755 cutoff value of 94.77 pg/mL, a sensitivity of 70.1%, and a specificity of 66.0%. Moreover, logistic regression analysis indicated that intraoperative hypothermia, decreased ALB levels, and increased CRP, IL-1 beta, and IL-17 levels on the first day after surgery were identified as risk factors for early AL in rectal cancer patients. Conclusions:This study found a significant elevation of IL-17 levels in the serum of patients who experienced early postoperative AL. Furthermore, intraoperative hypothermia and elevated IL-17 level

摘要： Myelodysplastic syndromes (MDS) are age-related diseases characterized by bone marrow (BM) dysfunction and an increased risk for developing acute leukemia. Although there is growing evidence that highlight the crucial role of the BM microenvironment (BMME) in MDS, the specific influence of inflammation on BMME changes and the potential benefits of targeting cytokines therapeutically remain to be elucidated. We previously found that interleukin-1 (IL-1) is a driver of aging phenotypes of the BMME and hematopoietic stem and progenitor cells (HSPCs). In this study, BM samples from patients with MDS demonstrated upregulated levels of IL-1 family cytokines, including IL-18. Using highly purified primary BM-derived mesenchymal stromal cells (MSCs), both IL-1b and IL18 were found to exert direct effects on MSCs, thus influencing their ability to support HSPCs and erythroid progenitors. This confirms the significant involvement of both these IL-1 family cytokines in regulating the BM niche. Furthermore, targeting IL-1 receptor type 1 mitigated these aging phenotypes in older mice. We subsequently employed an age-appropriate murine model of MDS by transplanting NUP98-HOXD13 transgenic mice (NHD13Tg) cells into aged wild-type mice. Treatment with inhibitors that targeted IL-1 receptor-associated kinase 4 (IRAK4) and NOD-like receptor family pyrin domain containing 3 (NLRP3) reversed the proliferation of dysfunctional MSCs and enhanced their functionality. In addition, IRAK4 inhibition selectively suppressed MDS clonal cells while sparing non-MDS cells in the BM. These findings suggest that targeting IL-1 signaling holds promise for MDS treatment by addressing the underlying myeloid malignancy and restoring the altered BMME via BM-MSCs.

关键词： p62   ASC   IL-1 beta   IL-10   IFN-I   IFN-beta   autophagy   inflammasome  

摘要： Macrophages are critical for the innate immune defense against the facultative intracellular Gram-negative bacterium Salmo\nella enterica serovar Typhimurium. Following phagocytosis by macrophages, S. Typhimurium activates cytoplasmic NLRC3 and NLRP4 inflammasomes, which share the adaptor ASC, resulting in the secretion of the pro-inflammatory cytokine IL-1 beta. To prevent excessive inflammation and tissue damage, inflammatory signaling pathways are tightly controlled. Recently, autophagy has been suggested to limit inflammation by targeting activated inflammasomes for autophagic degradation. However, the importance of the autophagic adaptor Sequestome-1 (hereafter, p62) for regulating inflammasome activation remains poorly understood. We report here that p62 restricts inflammasome availability and subsequent IL-1 beta secretion in macrophages infected with S. Typhimurium by targeting the inflammasome adaptor ASC for autophagic degradation. Importantly, loss of p62 resulted in impaired autophagy and increased IL-1 beta secretion, as well as IL-10 and IFN-beta release. In summary, our results demonstrate a novel role for p62 in inducing autophagy and balancing major pro- and anti-inflammatory signaling pathways to prevent excessive inflammation during S. Typhimurium infection of macrophages.

关键词： Flash nanocomplexation   Flash nanoprecipitation   TNF-alpha antibody   Sustained release   Hyaluronic acid hydrogel   Long-acting injectable   Inflammatory bowel disease   Chronic colitis  

摘要： Inflammatory bowel diseases (IBD) are chronic, remitting, and relapsing conditions of the gastrointestinal tract with incompletely elucidated etiology. The anti-TNF-alpha mAbs represent one of aflash nanocomplexation and flash nanoprecipitation process, resulting in particles with a narrow size distribution and tunable release profile, with the longest in vitro release lasting over four months. These mAb-releasing NPs are then incorporated into hyaluronic acid hydrogel microparticles (MPs) to enhance tissue retention, thus extending the duration of mAb release in vivo. A single i.m. injection of the LAI can maintain the serum mAb level above the therapeutically effective concentration for over 100 days in healthy mice. In a 9-week study using a dextran sulfate-induced chronic colitis model, the anti-TNF-alpha LAI formulation demonstrates substantial therapeutic efficacy and a better safety profile than free mAb injections. This work demonstrates the effectiveness of this LAI system in maintaining a persistent serum mAb level and its potential as a versatile, safer, and effective delivery system for antibody therapeutics.

关键词： IL-1 beta   intestinal inflammation organoid   intestinal stem cells   RNA-seq   NF-Kappa appa B/TNF/IL-17 signaling pathway  

摘要： Establishing an appropriate model of intestinal inflammation in vitro is crucial for studying the pathogenesis of inflammatory bowel disease (IBD). While immortalized cell lines have long been employed to investigate intestinal cell functions and host-pathogen interactions in sheep, they inadequately mimic the physiological characteristics of ovine intestinal inflammation and may lose critical genetic features. The emergence of organoids has revolutionized in vitro intestinal inflammation modeling by offering superior structural and functional fidelity to native tissues. In this study, we developed an IL-1 beta-induced intestinal inflammation organoid model derived from East Friesian sheep ileal crypts. Our data demonstrate that treatment with 30 ng/mL IL-1 beta significantly increased inflammatory factor secretion, the apoptosis of intermediate cells, and disrupted barrier integrity while simultaneously reducing bud formation capacity, organoid area, and stem cell proliferation. RNA-seq analysis revealed that IL-1 beta activated the NF-kappa B/TNF/IL-17 signaling pathway in intestinal organoids, thereby orchestrating the inflammatory response. This study establishes a novel sheep-derived intestinal inflammation organoid model, providing a physiologically relevant platform to investigate intestinal inflammation pathogenesis. These findings offer a translational tool for advancing drug development and pharmacological mechanism exploration in ovine intestinal inflammation research.

关键词： gastric cancer biomarkers   diagnosis and treatment   gastric cancer metastasis   tumor microenvironment   carcinoembryonic antigen (CEA)   cancer antigen 19-9 (CA19-9)   cancer antigen 72-4 (CA72-4)   alpha-fetoprotein (AFP)   tumor necrosis factor alpha (TNF-alpha)   inflammation and inflammatory parameters  

摘要： Background/Objectives: Gastric cancer remains a leading cause of cancer mortality worldwide. Reliable biomarkers are crucial for early detection, prognostication, and therapy monitoring. While classical tumor markers such as carcinoembryonic antigen (CEA), cancer antigen (CA)19-9, CA72-4, and alpha-fetoprotein (AFP) are used in clinical practice, their accuracy can be limited. Tumor necrosis factor alpha (TNF-alpha) is an inflammatory cytokine implicated in tumor progression, yet its relationship with established gastric cancer tumor markers has not been fully clarified. This study aimed to determine whether elevated TNF-alpha correlates with key tumor markers and disease stage in gastric cancer. Methods: In this prospective observational study, we enrolled 80 gastric cancer patients and 20 non-neoplastic controls. Baseline clinical data, laboratory parameters, and tumor markers (CEA, CA19-9, CA72-4, AFP) were recorded. TNF-alpha concentrations were measured using enzyme-linked immunosorbent assays. Correlation analyses and multivariate regression were performed to assess the relationship of TNF-alpha with tumor markers, inflammatory indices, and disease stage. Results: TNF-alpha was significantly elevated in gastric cancer patients (median 4.5 pg/mL) compared to controls (2.9 pg/mL). TNF-alpha showed a robust correlation with CA19-9 (rho = 0.502) and CA72-4 (rho = 0.385), and a moderate correlation with CEA (rho = 0.279). TNF-alpha concentrations were highest in Stage IV disease and in the intestinal-type histology. In regression analysis, only CA19-9 and CA72-4 remained independent predictors of TNF-alpha after controlling for clinical confounders. Conclusions: TNF-alpha is strongly associated with CA19-9 and CA72-4 and rises with advancing stage, highlighting its potential as an adjunct marker for assessing gastric cancer burden. These findings provide a rationale for further research on TNF-alpha as both a prognostic biomarker and a possible therapeutic target i