Lactate released by inflammatory bone marrow neutrophils induces their mobilization via endothelial GPR81 signaling
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE143978 | GEO | 2020/06/03
REPOSITORIES: GEO
Similar Datasets
Project description:Neutrophils provide first line of host defense against bacterial infections utilizing glycolysis for their effector functions. How glycolysis and its major byproduct lactate are triggered in bone marrow (BM) neutrophils and their contribution to neutrophil mobilization in acute inflammation is not clear. Here we report that bacterial lipopolysaccharides (LPS) or Salmonella Typhimurium triggers lactate release by increasing glycolysis, NADPH-oxidase-mediated reactive oxygen species and HIF-1α levels in BM neutrophils. Increased release of BM lactate preferentially promotes neutrophil mobilization by reducing endothelial VE-Cadherin expression, increasing BM vascular permeability via endothelial lactate-receptor GPR81 signaling. GPR81-/- mice mobilize reduced levels of neutrophils in response to LPS, unless rescued by VE-Cadherin disrupting antibodies. Lactate administration also induces release of the BM neutrophil mobilizers G-CSF, CXCL1 and CXCL2, indicating that this metabolite drives neutrophil mobilization via multiple pathways. Our study reveals a metabolic crosstalk between lactate-producing neutrophils and BM endothelium, which controls neutrophil mobilization under bacterial infection.
| S-EPMC7363928 | biostudies-literature
Project description:DNA Topoisomerase I inhibition by Camptothecin (CPT) derivatives can impair the hypoxia-induced cell transcriptional response. In the present work, we determined molecular aspects of the mechanism of CPT effects on HIF-1alpha activity in human cancer cells. In particular, we provide evidence that low concentrations of CPT, without interfering with HIF-1alpha mRNA levels, can reduce HIF-1alpha protein expression and activity. As luciferase assays demonstrated the involvement of the HIF-1alpha mRNA 3M-^RUTR in CPT-induced impairment of HIF-1alpha protein regulation, we performed microarray analysis to identify CPT-induced modification of miRNAs targeting HIF-1alpha mRNA under hypoxic-mimetic conditions. The selected miRNAs were then further analyzed demonstrating a role for miR-17-5p and miR-155 in HIF-1alpha protein expression after CPT treatments. The present findings establish miRNAs as key factors in a molecular pathway connecting Top1 inhibition and human HIF-1alpha protein regulation and activity, widening the biological and molecular activity of CPT derivatives and the perspective for novel clinical interventions.
2013-12-02 | E-MTAB-2022 | biostudies-arrayexpress
Project description:Lactate released by inflammatory bone marrow neutrophils induces their mobilization via endothelial GPR81 signaling
| PRJNA602422 | ENA
Project description:Autoantibodies against nucleic acids and excessive type I Interferon (IFN) are hallmarks of human Systemic Lupus Erythematosus (SLE). We previously reported that SLE neutrophils, exposed to TLR7-agonist autoantibodies, release interferogenic DNA, which we now demonstrate to be of mitochondrial origin. We further show that healthy human neutrophils do not complete mitophagy upon induction of mitochondrial damage. Rather, they extrude mitochondrial components, including DNA (mtDNA), devoid of oxidized residues. When MtDNA undergoes oxidation, it is directly routed to lysosomes for degradation. This rerouting requires dissociation from the transcription factor TFAM, a dual high mobility group (HMG) protein involved in maintenance and compaction of the mitochondrial genome into nucleoids. Exposure of SLE neutrophils, or healthy IFNprimed neutrophils, to anti-RNP autoantibodies blocks TFAM phosphorylation, a necessary step for nucleoid dissociation. Consequently, oxidized nucleoids accumulate within mitochondria and are eventually extruded as potent interferogenic complexes. In support of the in vivo relevance of this phenomenon, mitochondrial retention of oxidized nucleoids is a feature of SLE blood neutrophils, and autoantibodies against oxidized mtDNA are present in a fraction of patients. This pathway represents a novel therapeutic target in human SLE. 4 samples, no replicates, 2 controls. 2 samples are Neutrophils cultured with and without CCCP (control). 2 samples are Monocytes cultured with and without CCCP (control).
2016-04-07 | E-GEOD-78243 | biostudies-arrayexpress
Project description:Activation of glycolytic genes by HIF-1 is considered critical for metabolic adaptation to hypoxia. We found that HIF-1 also actively suppresses glucose metabolism through the tricarboxylic acid cycle (TCA) by directly trans-activating the gene encoding pyruvate dehydrogenase kinase 1 (PDK1). PDK1 inactivates the TCA cycle enzyme, pyruvate dehydrogenase (PDH), which converts pyruvate to acetyl-CoA. Forced PDK1 expression in hypoxic HIF-1α-null cells increases ATP levels, attenuates hypoxic ROS generation and rescues these cells from hypoxia-induced apoptosis. These studies reveal a novel hypoxia-induced metabolic switch that shunts glucose metabolites from the mitochondria to glycolysis to maintain ATP production and to prevent toxic ROS production. Experiment Overall Design: We sought to determine by microarray analysis of gene expression the genes responsive to hypoxia using the human B lymphocyte cell line, P493-6. Hypoxia-responsive genes were globally assessed in cells incubated in 0.1% O2 for 29 hours at which the highest HIF-1 levels were obtained
2008-06-12 | E-GEOD-4086 | biostudies-arrayexpress
Project description:Human renal cell carcinomas (RCC) have differential expression of HIF-1alpha and HIF-2alpha, depending on VHL genotype and other events. Here, we have divided a series of RCC samples for HIF-alpha expression and VHL genotype, in order to define differentially expressed genes Keywords: Patient Sample Study A total of 57 frozen RCC samples were stained for HIF-1alpha and HIF-2alpha, and genotyped for VHL. 5 VHL WT/HIF-negative, 8 VHL-deficient/HIF-1alpha+/HIF-2alpha+ and 8 VHL-deficient/HIF-2alpha+ tumors were selected for microarray
2008-12-27 | E-GEOD-11904 | biostudies-arrayexpress
Project description:Human renal cell carcinomas (RCC) have differential expression of HIF-1alpha and HIF-2alpha, depending on VHL genotype and other events. Here, we have divided a series of RCC samples based on HIF-alpha expression, in order to examine levels of genomic DNA aberration. Keywords: Patient Sample Study A total of 57 frozen RCC samples were stained for HIF-1alpha and HIF-2alpha, and genotyped for VHL. 10 VHL-deficient/HIF-1alpha+/HIF-2alpha+ and 11 VHL-deficient/HIF-2alpha+ tumors were selected for array CGH.
2008-12-27 | E-GEOD-13282 | biostudies-arrayexpress
Project description:Investigation whether hypoxic stabilization of HIF-1alpha quantitatively or qualitatively modifies the gene expression pattern induced by poly I:C, a TLR ligand that does not induce normoxic HIF-1alpha stabilization on its own (non-HIF-1alpha-stabilizing TLR ligand). Keywords: Comparison of single and combined treatment
2011-06-29 | GSE24995 | GEO
Project description:Autoantibodies against nucleic acids and excessive type I Interferon (IFN) are hallmarks of human Systemic Lupus Erythematosus (SLE). We previously reported that SLE neutrophils, exposed to TLR7-agonist autoantibodies, release interferogenic DNA, which we now demonstrate to be of mitochondrial origin. We further show that healthy human neutrophils do not complete mitophagy upon induction of mitochondrial damage. Rather, they extrude mitochondrial components, including DNA (mtDNA), devoid of oxidized residues. When MtDNA undergoes oxidation, it is directly routed to lysosomes for degradation. This rerouting requires dissociation from the transcription factor TFAM, a dual high mobility group (HMG) protein involved in maintenance and compaction of the mitochondrial genome into nucleoids. Exposure of SLE neutrophils, or healthy IFNprimed neutrophils, to anti-RNP autoantibodies blocks TFAM phosphorylation, a necessary step for nucleoid dissociation. Consequently, oxidized nucleoids accumulate within mitochondria and are eventually extruded as potent interferogenic complexes. In support of the in vivo relevance of this phenomenon, mitochondrial retention of oxidized nucleoids is a feature of SLE blood neutrophils, and autoantibodies against oxidized mtDNA are present in a fraction of patients. This pathway represents a novel therapeutic target in human SLE.
2016-04-07 | GSE78243 | GEO
Project description:Mitochondria can be involved in regulating cellular stress response to hypoxia and tumor growth, but little is known about that mechanistic relationship. Here, we show that mitochondrial deficiency severely retards tumor xenograft growth with impairing hypoxic induction of HIF-1 transcriptional activity. Using mtDNA-deficient rho0 cells, we found that HIF-1 pathway activation was comparable in slow-growing rho0 xenografts and rapid-growing parental xenografts. Interestingly, we found that ex vivo rho0 cells derived from rho0 xenografts exhibited slightly increased HIF-1alpha expression and modest HIF-1 pathway activation regardless of oxygen concentration. Surprisingly, rho0 cells, as well as parental cells treated with oxidative phosphorylation inhibitors, were unable to boost HIF-1 transcriptional activity during hypoxia, although HIF-1alpha protein levels were ordinarily increased in these cells under hypoxic conditions. These findings indicate that mitochondrial deficiency causes loss of hypoxia-induced HIF-1 transcriptional activity and thereby might lead to a constitutive HIF-1 pathway activation as a cellular adaptation mechanism in tumor microenvironment.
2017-01-01 | GSE80320 | GEO