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BACKGROUND: The incidence of exertional heat stroke (EHS) escalates during periods of elevated temperatures, potentially leading to persistent cognitive impairment postrecovery. Currently, effective prophylactic or therapeutic measures against EHS are nonexistent. METHODS: The selection of days 14 and 23 postinduction for detailed examination was guided by TEM of neuronal cells and HE staining of intestinal villi and the hippocampal regions. Fecal specimens from the ileum and cecum at these designated times were analyzed for changes in gut microbiota and metabolic products. Bioinformatic analyses facilitated the identification of pivotal microbial species and metabolites. The influence of supplementing these identified microorganisms on behavioral outcomes and the expression of functional proteins within the hippocampus was subsequently assessed. RESULTS: TEM analyses of neurons, coupled with HE staining of intestinal villi and the hippocampal region, indicated substantial recovery in intestinal morphology and neuronal injury on Day 14, indicating this time point for subsequent microbial and metabolomic analyses. Notably, a reduction in the Lactobacillaceae family, particularly Lactobacillus murinus, was observed. Functional annotation of 16S rDNA sequences suggested diminished lipid metabolism and glycan biosynthesis and metabolism in EHS models. Mice receiving this intervention (EHS + probiotics group) exhibited markedly reduced cognitive impairment and increased expression of BDNF/TrKB pathway molecules in the hippocampus during behavioral assessment on Day 28. CONCLUSION: Probiotic supplementation, specifically with Lactobacillus spp., appears to mitigate EHS-induced cognitive impairment, potentially through the modulation of the BDNF/TrKB signaling pathway within the hippocampus, illustrating the therapeutic potential of targeting the gut-brain axis.
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Disfunción Cognitiva , Microbioma Gastrointestinal , Golpe de Calor , Animales , Femenino , Masculino , Ratones , Eje Cerebro-Intestino , Disfunción Cognitiva/dietoterapia , Disfunción Cognitiva/etiología , Disfunción Cognitiva/microbiología , Disfunción Cognitiva/psicología , Microbioma Gastrointestinal/fisiología , Golpe de Calor/complicaciones , Golpe de Calor/metabolismo , Golpe de Calor/fisiopatología , Hipocampo/citología , Hipocampo/fisiopatología , Lactobacillus/metabolismo , Neuronas/ultraestructura , Probióticos , Conducta Animal , Ácidos Grasos Volátiles/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Exertional heatstroke (EHS) mainly occurs in healthy young people with rapid onset and high mortality. EHS immune disorders can cause systemic inflammatory responses and multiple organ failure; however, the underlying mechanisms remain unclear. As high mobility group box 1 (HMGB1) is a prototypical alarmin that activates inflammatory and immune responses, this study aimed to investigate the effect and mechanism of HMGB1 in the pathogenesis of EHS. METHODS: Peripheral blood mononuclear cell (PBMC) transcriptome sequencing of healthy volunteers, classical heatstroke patients, and EHS patients was performed. A mouse model of EHS was established and murine tissue damage was evaluated by H&E staining. HMGB1 localization and release were visualized using immunofluorescence staining. Human umbilical vein endothelial cells (HUVECs) and THP-1 cells were co-cultured to study the effects of HMGB1 on macrophages. A neutralizing anti-HMGB1 antibody was used to evaluate the efficacy of EHS treatment in mice. RESULTS: Plasma and serum HMGB1 levels were significantly increased in EHS patients or mice. EHS-induced endothelial cell pyroptosis promoted HMGB1 release in mice. HMGB1 derived from endothelial cell pyroptosis enhanced macrophage pyroptosis, resulting in immune disorders under EHS conditions. Administration of anti-HMGB1 markedly alleviated tissue injury and systemic inflammatory responses after EHS. CONCLUSIONS: The release of HMGB1 from pyroptotic endothelial cells after EHS promotes pyroptosis of macrophages and systemic inflammatory response, and HMGB1-neutralizing antibody therapy has good application prospects for EHS.
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Proteína HMGB1 , Golpe de Calor , Golpe de Calor/inmunología , Golpe de Calor/complicaciones , Golpe de Calor/metabolismo , Proteína HMGB1/metabolismo , Animales , Humanos , Ratones , Masculino , Células Endoteliales/metabolismo , Enfermedades del Sistema Inmune , FemeninoRESUMEN
Bacterial infection is the most common cause for sepsis. The purpose of this study was to evaluate the impact of different bacterial infection on sepsis based on human samples and cellular experiments. Physiological indexes and prognostic information of 121 sepsis patients were analysed based on whether they had a gram-positive or gram-negative bacterial infection. Moreover, murine RAW264.7 macrophages were treated with lipopolysaccharide (LPS) or peptidoglycan (PG) to simulate infection with gram-negative or gram-positive bacteria in sepsis, respectively. Exosomes derived from the macrophages were extracted for transcriptome sequencing. In patients with sepsis, most gram-positive bacterial infections were Staphylococcus aureus, and gram-negative infections were Escherichia coli. Gram-negative bacterial infection was significantly associated with high neutrophil and interleukin (IL)-6 levels in blood and shorter prothrombin (PT) and activated partial thromboplastin time (APTT). Intriguingly, the survival prognosis of sepsis patients was not affected by the type of bacterial infection, but it was significantly related to fibrinogen. Protein transcriptome sequencing of the macrophage-derived exosomes showed that differentially expressed proteins were significantly enriched in megakaryocyte differentiation, leukocyte and lymphocyte-mediated immunity, and complement and coagulation cascade pathways. The complement and coagulation-related proteins were significantly upregulated after LPS induction, which explained the shortened PT and APTT in gram-negative bacterial sepsis. Bacterial infection did not affect mortality in sepsis but did alter the host response. The immune disorder induced by gram-negative infection was more severe than that produced by gram-positive infection. This study provides references for the rapid identification and molecular research of different bacterial infections in sepsis.
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Infecciones por Bacterias Gramnegativas , Sepsis , Humanos , Ratones , Animales , Lipopolisacáridos , Inmunidad Innata , Infecciones por Bacterias Gramnegativas/etiología , Infecciones por Bacterias Gramnegativas/metabolismo , Escherichia coli/metabolismo , Interleucina-6/metabolismoRESUMEN
Liver transplantation (LT) is the best choice for patients with end-stage liver diseases. In order to better understand pathophysiological alterations in LT, we aimed to identify potential hub genes and inhibitory compounds involved in the LT process. Four pairs of peripheral blood mononuclear cell (PBMC) samples of the LT recipients before and after surgery were collected and taken for transcriptome sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed for the screened differentially expressed genes (DEGs) between pre- and post-operation groups. Common DEGs were obtained from GO and KEGG enriched pathways, followed by protein-protein interaction (PPI) network construction, hub gene identification, module analysis, and structure-based virtual screening process (SBVS). Compared to the pre-operation stage, 4745 genes were down-regulated and 798 up-regulated after LT. GO analysis showed that the DEGs were enriched in ribosome-related translation regulation, and KEGG analysis indicated that infection and immune-related pathways and diseases were largely enriched. A large number of down-regulated DEGs were not only associated with ribosome-related pathways but also with the alterations of epigenetic modifications, in particular ubiquitination. Moreover, through the PPI network of 29 common genes from GO and KEGG-enriched pathways, 7 hub genes were identified, including PTEN, MYC, EIF2S1, EIF4EBP1, HSP90AB1, TP53, and HSPA8, which were mainly involved in the PI3K-AKT signaling pathway. SBVS of the seed molecule PTEN (PDB code: 1D5R) predicted top hits compounds that may serve as potential inhibitors of PTEN, of which the compound ZINC4235331 had the lowest binding affinity of -10 kcal/mol. The significance of screened hub genes and potential inhibitors involved in the process of LT provides novel therapeutic strategies for improving the outcomes of LT recipients during surgery.
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Perfilación de la Expresión Génica , Trasplante de Hígado , Humanos , Transcriptoma/genética , Leucocitos Mononucleares , Fosfatidilinositol 3-Quinasas , Biología Computacional , Redes Reguladoras de GenesRESUMEN
Hemorrhagic shock (HS) is a global life-threatening matter that causes massive mortality annually worldwide. Syndecan-1 (SDC1) is an important predictor and evaluation index for HS, but its mechanism involved in the HS development remain unclear. HS mice model and human umbilical vein endothelial cells (HUVECs) under hypoxia were applied to explore the relationship of SDC1 with HIF-1α and NLRP3 inflammasome in vascular ECs under HS. Transcriptome sequencing of isolated vascular ECs were conduct to search for hub genes. Dual luciferase assay was adopted to prove the binding effects of the HIF-1α on SDC1 promoter in HUVECs. Molecular expression was evaluated through routine experiments. Here, HS led to aggravated lung injury and inflammatory response with the shedding of SDC1 on the lung vascular ECs in mice. Circulatory SDC1 and proinflammatory cytokines were significantly increased after HS. HIF-1α and IL-1ß were identified as hub genes in vascular ECs of HS mice. Meanwhile, HIF-1α-mediaed hypoxia and IL-1ß-involved NLRP3 inflammasome pathways were activated following HS. The transcriptional factor HIF-1α promoted the expression of SDC1 through binding to the SDC1 promoter. SDC1 had an inhibitory effect on the NLRP3 inflammasome activity. An exogenous increase of HIF-1α upregulated SDC1 and restrained the activation of the NLRP3 inflammasome under hypoxia, while further interference of SDC1 weakened this effect. Hence, SDC1 is an intermediate connecting HIF-1α and NLRP3 inflammasome in the vascular ECs under hypoxia. HIF-1α promotes the expression of SDC1 and inhibits the NLRP3 inflammasome pathway in vascular ECs under HS.
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Subunidad alfa del Factor 1 Inducible por Hipoxia , Inflamasomas , Choque Hemorrágico , Sindecano-1 , Animales , Humanos , Ratones , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Choque Hemorrágico/genética , Choque Hemorrágico/metabolismo , Sindecano-1/genéticaRESUMEN
Hemorrhagic shock (HS) is common in clinical emergencies, leading to millions of deaths each year globally. CD226 is a costimulatory adhesion molecule expressed on both immune cells and endothelial cells (ECs) to regulate their metabolic activity and function. As endothelial dysfunction occurs after HS, the roles CD226 plays in vascular EC metabolism were investigated. CD226fl/fl Tekcre mice were adopted to achieve vascular EC-specific knockout of CD226, and subjected to HS modelling. Serum levels of crucial intermediate metabolites were evaluated through liquid chromatography-mass spectrometry analysis. Human umbilical vein ECs (HUVECs) were used to study the effects of CD226 under hypoxia in vitro. Seahorse analysis evaluated the cellular glycolysis and mitochondria bioenergetics. Results showed that CD226 deficiency in vascular ECs alleviated HS-induced intestinal damage and inflammatory response in mice. Animal studies indicated an improved energy metabolism when CD226 was knocked out in ECs after HS, as evidenced by enhanced glutamine-glutamate metabolism and decreased lactic acid levels. Glut-1 was upregulated in mouse vascular ECs after HS and HUVECs under hypoxia, combined with decreased CD226. Moreover, HUVECs with CD226 knockdown exhibited relieved mitochondrial damage and early apoptosis under hypoxia, whereas CD226 overexpression showed opposite effects. Seahorse analysis showed that downregulated CD226 significantly increased mitochondrial ATP production and glucose uptake in HUVECs under hypoxia. Additionally, Erk/PHD2 signaling-mediated HIF-1α/Glut-1 and HIF-2α/ASCT2 pathways were involved in CD226 regulation on HUVEC glutaminolysis after hypoxia. Hence, CD226 deficiency promotes bypass energy supply to vascular ECs under ischemic or hypoxic stress, to ameliorate the stress-mediated metabolic disturbance.
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Antígenos de Diferenciación de Linfocitos T/fisiología , Hipoxia de la Célula , Mitocondrias/metabolismo , Choque Hemorrágico/metabolismo , Animales , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
Obesity is associated with chronic low-grade inflammation, contributing to an increasing prevalence of chronic metabolic diseases, such as insulin resistance, non-alcoholic fatty liver disease (NALFD), and steatohepatitis. Macrophages are the predominant immune cells in adipose tissues. Adipose tissue macrophages (ATMs) would switch to pro-inflammatory M1 state during obesity, causing local and systemic inflammation. However, the regulatory mechanism of ATMs has not yet been well described within this process. Using a high-fat diet (HFD)-induced mouse obesity model, we found that the costimulatory molecule CD226 was highly expressed on ATMs and knockout (KO) of CD226 alleviated obesity caused by HFD. Loss of CD226 reduced the accumulation of ATMs and hindered macrophage M1 polarization, with lower serum proinflammatory cytokine levels. Furthermore, deficiency of CD226 on ATMs decreased the phosphorylation levels of VAV1, AKT, and FOXO1 and thereby upregulated PPAR-γ. Further administration of PPAR-γ inhibitor restored M1 phenotype in CD226KO ATMs. In summary, loss of CD226 alleviates the HFD-induced obesity and systemic inflammation through inhibition of the accumulation and M1 polarization of ATMs in which PPAR-γ-dependent signaling pathway is involved, suggesting that CD226 may be identified as a potential molecular target for the clinical treatment of obesity.
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Dieta Alta en Grasa , Resistencia a la Insulina , Tejido Adiposo , Animales , Dieta Alta en Grasa/efectos adversos , Inflamación , Macrófagos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/genética , FenotipoRESUMEN
This study used constitutive CD226 gene knockout (KO) mice as a model to investigate the functions and mechanisms of CD226 in megakaryocyte (MK) maturation and platelet activation. Although CD226 deficiency did not cause MK polyploidization or platelet granule abnormalities, increased MK counts were detected in the femora bone marrow (BM) and spleen of CD226 KO mice. Particularly, CD226 KO mice have a more extensive membrane system in MKs and platelets than wild-type (WT) mice. We also demonstrated that CD226 KO mice displayed increased platelet counts, shortened bleeding time, and enhanced platelet aggregation. CD226 KO platelets had an increased mature platelet ratio compared to the control platelets. In addition, the observed reduction in bleeding time may be due to decreased nitric oxide (NO) production in the platelets. Platelet-specific CD226-deficient mice showed similar increased MK counts, shortened bleeding time, enhanced platelet aggregation, and decreased NO production in platelets. Furthermore, we performed middle cerebral artery occlusion-reperfusion surgery on WT and CD226 KO mice to explore the potential effect of CD226 on acute ischemia-reperfusion injury; the results revealed that CD226 deficiency led to significantly increased infarct area. Thus, CD226 is a promising candidate for the treatment of thrombotic disorders.
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Antígenos de Diferenciación de Linfocitos T/sangre , Megacariocitos/citología , Megacariocitos/fisiología , Activación Plaquetaria/fisiología , Animales , Antígenos de Diferenciación de Linfocitos T/genética , Plaquetas/fisiología , Plaquetas/ultraestructura , Isquemia Encefálica/sangre , Isquemia Encefálica/genética , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Femenino , Integrina beta3/sangre , Masculino , Megacariocitos/ultraestructura , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica de Transmisión , Activación Plaquetaria/genética , Adhesividad Plaquetaria/genética , Adhesividad Plaquetaria/fisiología , Agregación Plaquetaria/genética , Agregación Plaquetaria/fisiología , Recuento de Plaquetas , Trombopoyesis/genética , Trombopoyesis/fisiologíaRESUMEN
ADAR1 (adenosine deaminase acting on double-stranded RNA 1) is an RNA-editing enzyme that mediates adenosine-to-inosine RNA editing events, an important post-transcriptional modification mechanism that can alter the coding properties of mRNA or regulate microRNA biogenesis. ADAR1 also regulates the innate immune response. Here, we have demonstrated that ADAR1 expression increased in LPS-stimulated macrophages. Silencing ADAR1 by using small interfering RNA in macrophages resulted in the pronounced polarization of macrophages to M1, whereas ADAR1 overexpression promoted M2 polarization, which indicated that ADAR1 can inhibit macrophage hyperpolarization and prevent immune hyperactivity. The RNA-RNP immunoprecipitation binding assay demonstrated a direct interaction between ADAR1 and miR-21 precursor. Significant up-regulation in IL-10 and down-regulation in miR-21 were observed in ADAR1-overexpressing macrophages. We evaluated miR-21 target mRNAs and macrophage polarization signaling pathways and found that forkhead box protein O1 (Foxo1) was up-regulated in cells that overexpressed ADAR1. In a mouse allogeneic skin transplantation model, grafts in the ADAR1-overexpressed group survived longer and suffered less immune cell infiltration. In ADAR1-overexpressed recipients, splenic macrophages were significantly polarized to M2, and levels of sera IL-10 were markedly higher than those in the control group. In summary, ADAR1 modulates macrophage M2 polarization via the ADAR1-miR-21-Foxo1-IL-10 axis, thereby suppressing allogeneic graft rejection.-Li, J., Xie, J., Liu, S., Li, X., Zhang, D., Wang, X., Jiang, J., Hu, W., Zhang, Y., Jin, B., Zhuang, R., Yin, W. ADAR1 attenuates allogeneic graft rejection by suppressing miR-21 biogenesis in macrophages and promoting M2 polarization.
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Adenosina Desaminasa/metabolismo , Aloinjertos/metabolismo , Rechazo de Injerto/metabolismo , Macrófagos/metabolismo , MicroARNs/metabolismo , Animales , Regulación hacia Abajo/fisiología , Femenino , Proteína Forkhead Box O1/metabolismo , Inmunidad Innata/fisiología , Interleucina-10/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Transducción de Señal/fisiología , Regulación hacia Arriba/fisiologíaRESUMEN
Graft-versus-host disease (GVHD) is the most common complication and major limitation of allogeneic hematopoietic stem cell transplantation. The CD226/TIGIT-CD155 signal is critical for the cross-talk between T cells and dendritic cells (DCs). Studies have shown that blockade of the CD226-CD155 interaction, using an anti-CD226 antibody, can significantly ameliorate GVHD. It has also been reported that a TIGIT-Fc fusion protein exerts immunosuppressive effects by binding to CD155 on DCs. Here, we used a mouse allogeneic acute GVHD model to explore the therapeutic potential and mechanism of action of TIGIT-Fc. C57/BL6 and Balb/c mice were used as hematopoietic cell graft donors and recipients, respectively. In the TIGIT-Fc-treated mice, GVHD symptom occurrence and mortality were delayed compared to that in isotype control group mice. Histopathological analyses revealed that following TIGIT-Fc treatment, liver and small intestine tissue damage was reduced with minimal lymphocytic infiltration. The percentage of CD8+IFN-γ+ and CD8+ granzyme B+ cells significantly decreased in the TIGIT-Fc group. Moreover, treatment with TIGIT-Fc, even after the onset of GVHD, ameliorated symptoms and prolonged survival. TIGIT-Fc also inhibited CD8+ T cell activation in vitro; this was dependent on the presence of CD155 on bone marrow-derived dendritic cells (BMDCs) and on IL-10 production. In addition, TIGIT-CD155 ligation triggered both Erk phosphorylation and STAT3 nuclear translocation. These data indicate that TIGIT plays an important role in the development of GVHD and is an ideal molecular target to treat acute GVHD.
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Células Dendríticas/inmunología , Enfermedad Injerto contra Huésped/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Receptores Inmunológicos/metabolismo , Linfocitos T Citotóxicos/inmunología , Animales , Antígenos de Diferenciación de Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Enfermedad Injerto contra Huésped/epidemiología , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Tolerancia Inmunológica/inmunología , Fragmentos Fc de Inmunoglobulinas/genética , Fragmentos Fc de Inmunoglobulinas/inmunología , Fragmentos Fc de Inmunoglobulinas/metabolismo , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Receptores Virales/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Linfocitos T Citotóxicos/metabolismoRESUMEN
Formation of macrophage-derived foam cells may mark the initial stages of atherosclerosis. We investigated the association between the expression of the leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1) in macrophages and foam cell formation. A foam cell model was established by incubating THP-1-derived macrophages and bone marrow macrophages (BMMs) with oxidized low-density lipoprotein (ox-LDL). The role of LAIR-1 in foam cell formation was evaluated via Oil Red O staining and Dil-ox-LDL fluorescence intensities. Peroxisome proliferator-activated receptor gamma (PPARγ), cholesterol metabolism-related genes, and the role of LAIR-1 in activating classically activated (M1) and alternatively activated (M2) macrophages were evaluated by qPCR. Additionally, activation of protein-tyrosine phosphatase-1 (SHP-1) and cAMP-response element binding protein (CREB) were detected by western blotting. Results indicated that silencing LAIR-1 in macrophages modulated the SHP-1/CREB/PPARγ pathway, thereby promoting M2 macrophage polarization and increasing foam cell formation. Therefore, Inhibition of LAIR-1 in macrophages may promote foam cell formation and atherosclerosis.
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Células Espumosas/metabolismo , Macrófagos/metabolismo , PPAR gamma/metabolismo , Receptores Inmunológicos/metabolismo , Células THP-1/metabolismo , Animales , Aterosclerosis/metabolismo , Línea Celular , Colesterol/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Humanos , Metabolismo de los Lípidos/fisiología , Lipoproteínas LDL/metabolismo , Ratones , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Células RAW 264.7 , Transducción de Señal/fisiologíaRESUMEN
Adenosine deaminase acting on RNA 1 (ADAR1), a double-stranded RNA-editing enzyme that converts adenosine (A) to inosine (I), has been identified as a modulator of immune responses. However, the role of ADAR1 in small intestinal homeostasis during sepsis remains unclear. In this study, we examined the role of ADAR1 on intestinal inflammation in a murine model of sepsis. We found that ADAR1 was highly expressed in "septic" macrophages and small intestinal tissue of septic mice. Deletion of ADAR1 in "septic" macrophages led to rapid apoptosis. In addition, suppression of ADAR1 in "septic" macrophages significantly enhanced inflammation, while over-expression of ADAR1 significantly suppressed the level of inflammatory cytokines. Furthermore, suppression of ADAR1 in septic mice significantly enhanced inflammation and intestinal damage, while enhanced ADAR1 expression resulted in reduced damage and inflammation. Finally, over-expression of ADAR1 improved survival of septic mice. In conclusion, we have identified a novel ADAR1 protective effect for maintaining intestinal homeostasis. Our findings may provide a new targeted therapy for sepsis treatment.
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Adenosina Desaminasa/metabolismo , Inflamación/metabolismo , Inflamación/patología , Intestino Delgado/lesiones , Intestino Delgado/metabolismo , Sepsis/metabolismo , Sepsis/patología , Animales , Apoptosis , Citocinas/metabolismo , Modelos Animales de Enfermedad , Eliminación de Gen , Mediadores de Inflamación/metabolismo , Intestino Delgado/patología , Estimación de Kaplan-Meier , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Células RAW 264.7RESUMEN
Acute lung injury is a serious complication of sepsis with high morbidity and mortality. Pyroptosis is a proinflammatory form of programmed cell death that leads to immune dysregulation and organ dysfunction during sepsis. We previously found that adenosine deaminase acting on double-stranded RNA 1 (ADAR1) plays regulatory roles in the pathology of sepsis, but the mechanism of ADAR1 in sepsis-induced pyroptosis and lung injury remains unclear. Here, we mainly investigated the regulatory effects and underlying mechanism of ADAR1 in sepsis-induced lung injury and pyroptosis of pulmonary macrophages through RNA sequencing of clinical samples, caecal ligation and puncture (CLP)-induced septic mouse models, and in vitro cellular experiments using RAW264.7 cells with lipopolysaccharide (LPS) stimulation. The results showed that pyroptosis was activated in peripheral blood mononuclear cells (PBMCs) from patients with sepsis. In the CLP-induced septic mouse model, pyroptosis was mainly activated in pulmonary macrophages. LPS-stimulated RAW264.7 cells showed significantly increased activation of the NLRP3 inflammasome. ADAR1 was downregulated in PMBCs of patients with sepsis, and overexpression of ADAR1 alleviated CLP-induced lung injury and NLRP3 inflammasome activation. Mechanistically, the regulatory effects of ADAR1 on macrophage pyroptosis were mediated by the miR-21/A20/NLRP3 signalling cascade. ADAR1 attenuated sepsis-induced lung injury and hindered the activation of pyroptosis in pulmonary macrophages in sepsis through the miR-21/A20/NLRP3 axis. Our study highlights the role of ADAR1 in protecting pulmonary macrophages against pyroptosis and suggests targeting ADAR1/miR-21 signalling as a therapeutic opportunity in sepsis-related lung injury.
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Lesión Pulmonar Aguda , MicroARNs , Sepsis , Animales , Humanos , Ratones , Adenosina Desaminasa/genética , Modelos Animales de Enfermedad , Inflamasomas , Leucocitos Mononucleares , Lipopolisacáridos/farmacología , Macrófagos Alveolares , MicroARNs/genética , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Piroptosis , Sepsis/complicaciones , Sepsis/genéticaRESUMEN
Background and Aims: As sepsis progresses, immune cell apoptosis plays regulatory roles in the pathogenesis of immunosuppression and organ failure. We previously reported that adenosine deaminases acting on RNA-1 (ADAR1) reduced intestinal and splenic inflammatory damage during sepsis. However, the roles and mechanism of ADAR1 in sepsis-induced liver injury remain unclear. Methods: We performed transcriptome and single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) from patients with sepsis to investigate the effects of ADAR1 on immune cell activities. We also employed a cecal ligation and puncture (CLP) sepsis mouse model to evaluate the roles of ADAR1 in sepsis-induced liver injury. Finally, we treated murine RAW 264.7 macrophages with lipopolysaccharide to explore the underlying ADAR1-mediated mechanisms in sepsis. Results: PBMCs from patients with sepsis had obvious apoptotic morphological features. Single-cell RNA sequencing indicated that apoptosis-related pathways were enriched in monocytes, with significantly elevated ADAR1 and BCL2A1 expression in severe sepsis. CLP-induced septic mice had aggravated liver injury and Kupffer cell apoptosis that were largely alleviated by ADAR1 overexpression. ADAR1 directly bound to pre-miR-122 to modulate miR-122 biosynthesis. miR-122 was an upstream regulator of BCL2A1. Furthermore, ADAR1 also reduced macrophage apoptosis in mice with CLP-induced sepsis through the miR-122/BCL2A1 signaling pathway and protected against sepsis-induced liver injury. Conclusions: The findings show that ADAR1 alleviates macrophage apoptosis and sepsis-induced liver damage through the miR-122/BCL2A1 signaling pathway. The study provides novel insights into the development of therapeutic interventions in sepsis.
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Liver ischemia and reperfusion injury (LIRI) is a major risk for the poor prognosis of patients receiving liver transplantation. The molecular mechanism involved in LIRI is complex and related to various cellular components. We previously reported that adenosine deaminase acting on RNA 1 (ADAR1) alleviated the allogeneic skin graft rejection by regulating macrophage polarization. However, the regulatory effects of ADAR1 on liver macrophages after LIRI remain largely unknown. In this study, we mainly adopted a mouse model of LIRI and cellular experiments with hypoxia and reoxygenation (HR) treatment to explore the regulatory roles of ADAR1 on liver macrophages under LIRI conditions. We found that IRI caused decreased ADAR1 in liver tissues and remarkable changes of liver macrophage polarization and profiles. ADAR1 supplementation alleviated the pathological injury caused by IRI and accelerated the activation of M2 macrophages in the liver of IRI mice. Increased hypoxia duration reduced ADAR1 expression levels in murine RAW264.7 macrophages at the transcriptional level. Further overexpression of ADAR1 significantly increased the expressions of anti-inflammatory cytokines and promoted M2 polarization of macrophages under HR exposure. ADAR1 knockdown exhibited opposite effects on macrophage polarization. Hence, ADAR1 promotes the M2 polarization of liver macrophages that may further alleviate LIRI. The protective effects of ADAR1 against LIRI provide a novel insight into the prevention and treatment of LIRI.
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Hígado , Daño por Reperfusión , Humanos , Ratones , Animales , Hígado/patología , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Daño por Reperfusión/prevención & control , Macrófagos/metabolismo , Isquemia/complicaciones , Isquemia/metabolismo , Isquemia/patología , Hipoxia/complicaciones , Hipoxia/metabolismo , Hipoxia/patología , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismoRESUMEN
Objective: The early targeted and effective diagnosis and treatment of severe trauma are crucial for patients' outcomes. Blood leukocytes act as significant effectors during the initial inflammation and activation of innate immunity in trauma. This study aims to identify hub genes related to patients' prognosis in blood leukocytes at the early stages of trauma. Methods: The expression profiles of Gene Expression Omnibus (GEO) Series (GSE) 36809 and GSE11375 were downloaded from the GEO database. R software, GraphPad Prism 9.3.1 software, STRING database, and Cytoscape software were used to process the data and identify hub genes in blood leukocytes of early trauma. Results: Gene Ontology (GO) analysis showed that the differentially expressed genes (DEGs) of blood leukocytes at the early stages of trauma (0-4 h, 4-8 h, and 8-12 h) were mainly involved in neutrophil activation and neutrophil degranulation, neutrophil activation involved in immune response, neutrophil mediated immunity, lymphocyte differentiation, and cell killing. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEGs were mainly involved in Osteoclast differentiation and Hematopoietic cell lineage. Sixty-six down-regulated DEGs and 148 up-regulated DEGs were identified and 37 hub genes were confirmed by Molecular Complex Detection (MCODE) of Cytoscape. Among the hub genes, Lipocalin 2 (LCN2), Lactotransferrin (LTF), Olfactomedin 4 (OLFM4), Resistin (RETN), and Transcobalamin 1 (TCN1) were related to prognosis and connected with iron transport closely. LCN2 and LTF were involved in iron transport and had a moderate predictive value for the poor prognosis of trauma patients, and the AUC of LCN2 and LTF was 0.7777 and 0.7843, respectively. Conclusion: As iron transport-related hub genes in blood leukocytes, LCN2 and LTF can be used for prognostic prediction of early trauma.
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Background: Survivors of sepsis may encounter cognitive impairment following their recovery from critical condition. At present, there is no standardized treatment for addressing sepsis-associated encephalopathy. Lactobacillus rhamnosus GG (LGG) is a prevalent bacterium found in the gut microbiota and is an active component of probiotic supplements. LGG has demonstrated to be associated with cognitive improvement. This study explored whether LGG administration prior to and following induced sepsis could ameliorate cognitive deficits, and explored potential mechanisms. Methods: Female C57BL/6 mice were randomly divided into three groups: sham surgery, cecal ligation and puncture (CLP), and CLP+LGG. Cognitive behavior was assessed longitudinally at 7-9d, 14-16d, and 21-23d after surgery using an open field test and novel object recognition test. The impact of LGG treatment on pathological changes, the expression level of brain-derived neurotrophic factor (BDNF), and the phosphorylation level of the TrkB receptor (p-TrkB) in the hippocampus of mice at two weeks post-CLP (16d) were evaluated using histological, immunofluorescence, immunohistochemistry, and western blot analyses. Results: The CLP surgery induced and sustained cognitive impairment in mice with sepsis for a minimum of three weeks following the surgery. Compared to mice subjected to CLP alone, the administration of LGG improved the survival of mice with sepsis and notably enhanced their cognitive functioning. Moreover, LGG supplementation significantly alleviated the decrease in hippocampal BDNF expression and p-TrkB phosphorylation levels caused by sepsis, preserving neuronal survival and mitigating the pathological changes within the hippocampus of mice with sepsis. LGG supplementation mitigates sepsis-related cognitive impairment in mice and preserves BDNF expression and p-TrkB levels in the hippocampus.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Disfunción Cognitiva , Hipocampo , Lacticaseibacillus rhamnosus , Ratones Endogámicos C57BL , Probióticos , Sepsis , Animales , Sepsis/complicaciones , Sepsis/terapia , Sepsis/microbiología , Sepsis/metabolismo , Disfunción Cognitiva/terapia , Disfunción Cognitiva/etiología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Femenino , Ratones , Hipocampo/metabolismo , Probióticos/farmacología , Probióticos/administración & dosificación , Probióticos/uso terapéutico , Modelos Animales de Enfermedad , Receptor trkB/metabolismo , Encefalopatía Asociada a la Sepsis/metabolismo , Encefalopatía Asociada a la Sepsis/patología , Encefalopatía Asociada a la Sepsis/dietoterapia , FosforilaciónRESUMEN
This study aims to reveal the metabolic differences between SDC-1 knockout mice and wild-type mice and the metabolic differences caused by shock in SDC-1 knockout mice by integrating transcriptomics and metabolomics. A total of 1009 differential metabolites were differentially expressed based on untargeted metabolomics and high-resolution mass spectrometry detection techniques. According to Kyoto Encyclopedia of Genes and Genomes enrichment, SDC-1 knockout significantly altered fat digestion and absorption, GnRH signaling pathway, fructose and mannose metabolism, and some other amino-related metabolic pathways and significantly modulated positively regulated longevity regulatory pathways, longevity regulatory pathways-worm, nicotinamide and niacinamide metabolism, and vitamin digestion and absorption pathways after its shock. Our findings indicate that SDC-1 knockout may have potential therapeutic effects in hemorrhagic shock by increasing nicotinamide metabolism.
RESUMEN
BACKGROUND: The predictive value of biomarkers such as neuron specific enolase (NSE), S100B, neurofilament (NFL), interleukin-6 (IL-6), coagulation factor R, and D-Dimer (DD) after acute Stanford A type aortic dissection (AAAD) with neurological complications has recently gained much attention from the research community. However, results from these studies are conflicting. This meta-analysis is conducted to assess the relationship between the biomarkers and the risk of neurological complications after AAAD. METHODS: Two reviewers performed a systematic literature search across eight databases (CNKI, Wan Fang, VIP, CBM, PubMed, Web of Science, Cochrane Library, and EMBASE). The studies regarding biomarkers in AAAD patients published up to February 2022 were included. These studies were subjected to rigorous scrutiny and data extraction to determine the weighted mean difference (WMD) and the 95% confidence interval (CI), which were analyzed using the RevMan 5.4 and Stata software 14.0. RESULTS: A total of 12 studies including 360 cases with neurological complications and 766 controls were incorporated into our meta-analysis. WMD analysis showed that there was a higher NSE levels in AAAD patients with postoperative neurological complications compared with controls (WMD = 0.640, 95% CI: 0.205 ~ 1.075, P = 0.004 < 0.005), and the level of S100B was related to the 6 h and 24 h postoperative neurological complications (6 h: WMD = 0.64, 95% CI: 0.27 ~ 1.02, P = 0.0007 < 0.001; 24 h: WMD = 0.281, 95% CI: 0.211 ~ 0.351, P < 0.001). Moreover, S100B levels at 6 hours after operation were significantly higher than that at 24 hours (WMD = 0.260, 95% CI: 0.166 ~ 0.354, P < 0.001). CONCLUSION: NSE and S100B are both candidate biomarkers to predict postoperative neurological complications in patients with AAAD. Other markers are also valuable when used in conjunction with clinical judgement. The findings accentuate the necessity of further research to establish standardized values for these biomarkers in predicting neurological complications.