The gut microbiota regulates the vascular inflammatory phenotype in mesenteric ischemia-reperfusion injury via endothelial Toll-like receptor-2 signaling
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE295338 | GEO | 2025/04/23
REPOSITORIES: GEO
Similar Datasets
Project description:Endothelial cell (EC) Toll-like receptor 2 (TLR2) activation upregulates the expression of inflammatory mediators and of TLR2 itself, and modulates important endothelial functions, including coagulation and permeability. We defined TLR2 signaling pathways in ECs, and tested the hypothesis that TLR2 signaling differs in ECs and monocytes. We found that ERK5, heretofore unrecognized as mediating TLR2 activation in any cell type, is a central mediator of TLR2-dependent inflammatory signaling in HUVEC, primary human lung microvascular ECs and human monocytes. Additionally, we observed that whereas MEK1 negatively regulates TLR2 signaling in EC, MEK1 promotes TLR2 signaling in monocytes. We also noted that activation of TLR2 led to the upregulation of intracellularly expressed TLR2 and inflammatory mediators via NF-κB, JNK and p38-MAPK. Finally, we found that p38-MAPK, JNK, ERK5 and NF-κB promote the attachment of human neutrophils to lung microvascular EC that were pretreated with TLR2 agonists. This study newly identifies ERK5 as a key regulator of TLR2 signaling in ECs and monocytes, and indicates that there are fundamental differences in TLR signaling pathways between EC and monocytes.
2011-11-04 | GSE33449 | GEO
Project description:Endothelial cell (EC) Toll-like receptor 2 (TLR2) activation upregulates the expression of inflammatory mediators and of TLR2 itself, and modulates important endothelial functions, including coagulation and permeability. We defined TLR2 signaling pathways in ECs, and tested the hypothesis that TLR2 signaling differs in ECs and monocytes. We found that ERK5, heretofore unrecognized as mediating TLR2 activation in any cell type, is a central mediator of TLR2-dependent inflammatory signaling in HUVEC, primary human lung microvascular ECs and human monocytes. Additionally, we observed that whereas MEK1 negatively regulates TLR2 signaling in EC, MEK1 promotes TLR2 signaling in monocytes. We also noted that activation of TLR2 led to the upregulation of intracellularly expressed TLR2 and inflammatory mediators via NF-M-NM-:B, JNK and p38-MAPK. Finally, we found that p38-MAPK, JNK, ERK5 and NF-M-NM-:B promote the attachment of human neutrophils to lung microvascular EC that were pretreated with TLR2 agonists. This study newly identifies ERK5 as a key regulator of TLR2 signaling in ECs and monocytes, and indicates that there are fundamental differences in TLR signaling pathways between EC and monocytes. qPCR gene expression profiling. HUVEC monolayers were grown to confluency in EGM-2 media. THP1 suspension cells were grown RPMI 1640 supplemented with 10% FBS, L-glutamine, and antibiotics. Neither cell line was treated with any agonists. RQ values were calculated using the 2-M-NM-^TM-NM-^TCt method. Two biological replicates and one technical replicate were analyzed for both cell lines.
2011-11-04 | E-GEOD-33449 | biostudies-arrayexpress
Project description:This file contains gene microarray data from FACS purified mouse high endothelial cells and capillary endothelial cells from peripheral lymph nodes, mesenteric lymph nodes, and Peyer’s patches. The data will allow for better understanding of the specialization of high endothelial venules (HEV) and their role in lymphocyte recruitment from the blood; the tissue-specific differentiation of lymphoid tissue vasculature; and the specialized features of capillary vs. post-capillary endothelium, including differences in signaling pathways, adhesive properties and mechanisms of hemostasis. We analyzed transcript expression data from vascular endothelial subsets from BALB/c mouse lymphoid tissue.
2014-08-31 | E-GEOD-58056 | biostudies-arrayexpress
Project description:Monocytes and macrophages are essential cells in the early response in their capacity as ubiquitous phagocytic cells. They phagocytose microorganisms or damaged cells and sense pathogen/damage-associated molecular patterns (PAMPs/DAMPs) through innate receptors such as Toll-like receptors (TLRs). We investigated a phenomenon where co-signaling from TLR2 and TLR8 in human primary monocytes provides a distinct immune activation profile compared to signaling from either TLR alone. Comparison of gene signatures induced by either stimulus alone or together, show that co-signaling result in downstream differences in regulation of signaling and gene transcription. To investigate the interaction of TLR2 and TLR8 stimulation primary human monocytes isolated from buffy coat were stimulated with TLR2/6 ligand FSL-1 and/or TLR7/8 ligand CL075 and the gene expression monitored at 1,2 and 3h post stimulation.
2018-03-09 | E-MTAB-6222 | biostudies-arrayexpress
Project description:Microglia are the resident mononuclear phagocytes of the CNS parenchyma and represent an initial line of defense against invading microorganisms. Microglia utilize Toll-like receptors (TLRs) for pathogen recognition and TLR2 specifically senses conserved motifs of gram-positive bacteria including lipoproteins, lipoteichoic acids, and peptidoglycan (PGN) leading to cytokine/chemokine production. Interestingly, primary microglia derived from TLR2 knockout (KO) mice over-expressed numerous IL-12 family members, including IL-12p40, IL-12p70, and IL-27 in response to intact S. aureus, but not the less structurally complex TLR2 ligands Pam3CSK4 or PGN. The ability of intact bacteria to augment IL-12 family member expression was specific for gram-positive organisms, since numerous gram-negative strains were unable to elicit exaggerated responses in TLR2 KO microglia. Inhibition of SYK or IRAK4 signaling did not impact heightened IL-12 family member production in S. aureus-treated TLR2 KO microglia, whereas PI3K, MAPK, and JNK inhibitors were all capable of restoring exaggerated cytokine expression to wild type levels. Additionally, elevated IL-12 production in TLR2 KO microglia was ablated by a TLR9 antagonist, suggesting that TLR9 drives IL-12 family member production following exposure to intact bacteria that remains unchecked in the absence of TLR2 signaling. Collectively, these findings indicate crosstalk between TLR2 and TLR9 pathways to regulate IL-12 family member production by microglia. The summation of TLR signals must be tightly controlled to ensure the timely cessation and/or fine tuning of cytokine signaling to avoid nonspecific bystander damage due to sustained IL-12 release.
2014-12-22 | GSE24935 | GEO
Project description:Microglia are the resident mononuclear phagocytes of the CNS parenchyma and represent an initial line of defense against invading microorganisms. Microglia utilize Toll-like receptors (TLRs) for pathogen recognition and TLR2 specifically senses conserved motifs of gram-positive bacteria including lipoproteins, lipoteichoic acids, and peptidoglycan (PGN) leading to cytokine/chemokine production. Interestingly, primary microglia derived from TLR2 knockout (KO) mice over-expressed numerous IL-12 family members, including IL-12p40, IL-12p70, and IL-27 in response to intact S. aureus, but not the less structurally complex TLR2 ligands Pam3CSK4 or PGN. The ability of intact bacteria to augment IL-12 family member expression was specific for gram-positive organisms, since numerous gram-negative strains were unable to elicit exaggerated responses in TLR2 KO microglia. Inhibition of SYK or IRAK4 signaling did not impact heightened IL-12 family member production in S. aureus-treated TLR2 KO microglia, whereas PI3K, MAPK, and JNK inhibitors were all capable of restoring exaggerated cytokine expression to wild type levels. Additionally, elevated IL-12 production in TLR2 KO microglia was ablated by a TLR9 antagonist, suggesting that TLR9 drives IL-12 family member production following exposure to intact bacteria that remains unchecked in the absence of TLR2 signaling. Collectively, these findings indicate crosstalk between TLR2 and TLR9 pathways to regulate IL-12 family member production by microglia. The summation of TLR signals must be tightly controlled to ensure the timely cessation and/or fine tuning of cytokine signaling to avoid nonspecific bystander damage due to sustained IL-12 release. TLR2 KO mice were backcrossed with C57BL/6 animals for a minimum of eight generations prior to use in these studies. Age- and sex-matched C57BL/6 mice were used as wild type (WT) controls. Primary mixed glial cultures were prepared from the cerebral corticies of neonatal mice (2-4 days of age) and microglia were harvested using a differential shaking technique with a purity of >98%. A USA300 community-acquired methicillin-resistant S. aureus (CA-MRSA) clinical isolate recovered from a patient with a fatal brain abscess was used to stimulate the microglia isolates. Bacterial strains were heat-inactivated and used to stimulate microglia at 107 colony forming units (cfu)/well for 6 and 12 hours time points. Three replicates of each mouse type (WT, TLR2 KO) at both time points 6 and 12 hours were used for the microarray experiments. Data was only usable for 2 replicates of the KO-12 hr group.
2014-12-22 | E-GEOD-24935 | biostudies-arrayexpress
Project description:Sepsis caused by Gram-positive bacterial pathogens is a major fatal disease but its molecular basis remains elusive. Toll-like receptor 2 (TLR2) has been implicated in the orchestration of inflammation and sepsis but its role appears to vary for different pathogen species and clones. Accordingly, Staphylococcus aureus clinical isolates differ substantially in their capacity to activate TLR2. Here we show that strong TLR2 stimulation depends on high-level production of phenol-soluble modulin (PSM) peptides in response to the global virulence activator Agr. PSMs are required for mobilizing lipoproteins, the TLR2 agonists, from the staphylococcal cytoplasmic membrane. Notably, the course of sepsis caused by PSM-deficient S. aureus is similar in wild-type and TLR2-deficient mice, but TLR2 is required for protection of mice against PSM-producing S. aureus. Thus, a crucial role of TLR2 depends on agonist release by bacterial surfactants. Modulation of this process may lead to new therapeutic strategies against Gram-positive infections.
2016-06-08 | PXD004283 | Pride
Project description:Ulcerative colitis (UC) is an intestinal pathology characterized by chronic recurrent inflammation, which requires in-depth exploration of its mechanisms. To investigate the biological effects of TLR2 on DSS-induced intestinal inflammation in mice, we constructed the WT and TLR2-KO colitis mice model. We found TLR2-KO mice were severely susceptible to DSS-induced colitis. To determine how TLR2 exerted a protective effect in DSS-induced colitis, we compared the global gene expression profiles in the gut between WT and TLR2-KO mice by RNA-Seq. Results suggested that cell cycle pathway-related genes were significantly downregulated in gut of TLR2-KO colitis mice. 16S rRNA gene sequencing demonstrated remarkable variation in the composition of gut microbiota between WT and TLR2-KO colitis mice. Compared with WT colitis mice, the relative abundance of Marinifilaceae, Rikenellaceae, Desulfovibrionaceae, Tannerellaceae, Ruminococcaceae, Clostridia, Mycoplasmataceae were significantly higher in the gut of TLR2-KO colitis mice at family level. Moreover, we found that the relative abundance of Marinifilaceae was negatively correlated with the expression of cell cycle signaling related genes by microbiome diversity-transcriptome collaboration analysis. We came to this conclusion: TLR 2-KO exacerbated DSS-induced intestinal injury by Marinifilaceae dependent attenuating cell cycle signaling.
2025-04-01 | GSE265856 | GEO
Project description:Background: Mesenchymal stem/stromal cells (MSCs) maintain tissue homeostasis in response to microenvironmental perturbations. Toll-like receptors (TLRs) are key sensors for exogenous and endogenous signals produced during injury. In this study, we aimed to investigate whether TLRs affect the homeostatic functions of MSCs after injury. Methods: We examined the expression of TLR2, TLR3 and TLR4 in MSCs, and analyzed the functional significance of TLR2 activation using single-cell RNA sequencing. Additionally, we investigated the effects and mechanisms of TLR2 and its downstream activation in MSCs on monocytes/macrophages and a mouse model of sterile injury-induced inflammatory corneal angiogenesis. Results: MSCs expressed TLR2, which was upregulated by monocytes/macrophages. Activation of TLR2 in MSCs promoted their immunoregulatory and angiostatic functions in monocytes/macrophages and in mice with inflammatory corneal angiogenesis, whereas TLR2 inhibition attenuated these functions. Single-cell RNA sequencing revealed AKR1C1, a gene encoding aldo-keto reductase family 1 member C1, as the most significantly inducible gene in MSCs upon TLR2 stimulation, though its stimulation did not affect cell compositions. AKR1C1 protected MSCs against ferroptosis, increased secretion of anti-inflammatory cytokines, and enhanced their ability to drive monocytes/macrophages towards immunoregulatory phenotypes, leading to amelioration of inflammatory corneal neovascularization in mice. Conclusion: Our findings suggest that activation of TLR2-AKR1C1 signaling in MSCs serves as an important pathway for MSCs’ survival and homeostatic activities during injury.
2024-10-01 | GSE273279 | GEO
Project description:The interaction between monocytes and endothelial cells in inflammation is central to chemoattraction, adhesion, and transendothelial migration. Key players such as selectins and their ligands, integrins and other adhesion molecules and their function in these processes are well studied. Toll-like receptor 2 (TLR2), expressed on monocytes, is critical for sensing invading pathogens and initiating a rapid and effective immune response. However, the extended role of TLR2 in monocyte adhesion and migration has only been partially elucidated. To address this question, we performed several functional cell-based assays using monocyte-like wild type (WT), TLR2-knock-out (KO) and, TLR2-knock-in (KI) THP-1 cells. We found that TLR2 promotes faster and stronger adhesion of monocytes to the endothelium and a more intense endothelial barrier disruption after endothelial activation. In addition, we performed quantitative mass-spectrometry, STRING protein analysis, and RT-qPCR, which revealed the association of TLR2 with specific integrins, but also uncovered novel proteins affected by TLR2. In conclusion, we could show that unstimulated TLR2 affects cell adhesion, endothelial barrier disruption, migration, and actin polymerization.
2023-10-24 | PXD041819 | Pride