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PloS One 2017A crucial role of cell metabolism in immune cell differentiation and function has been recently established. Growing evidence indicates that metabolic processes impact...
A crucial role of cell metabolism in immune cell differentiation and function has been recently established. Growing evidence indicates that metabolic processes impact both, innate and adaptive immunity. Since a down-stream integrator of metabolic alterations, mammalian target of rapamycin (mTOR), is responsible for controlling the balance between pro-inflammatory interleukin (IL)-12 and anti-inflammatory IL-10, we investigated the effect of upstream interference using metabolic modulators on the production of pro- and anti-inflammatory cytokines. Cytokine release and protein expression in human and murine myeloid cells was assessed after toll-like receptor (TLR)-activation and glucose-deprivation or co-treatment with 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPK) activators. Additionally, the impact of metabolic interference was analysed in an in-vivo mouse model. Glucose-deprivation by 2-deoxy-D-glucose (2-DG) increased the production of IL-12p40 and IL-23p19 in monocytes, but dose-dependently inhibited the release of anti-inflammatory IL-10. Similar effects have been observed using pharmacological AMPK activation. Consistently, an inhibition of the tuberous sclerosis complex-mTOR pathway was observed. In line with our in vitro observations, glycolysis inhibition with 2-DG showed significantly reduced bacterial burden in a Th2-prone Listeria monocytogenes mouse infection model. In conclusion, we showed that fasting metabolism modulates the IL-12/IL-10 cytokine balance, establishing novel targets for metabolism-based immune-modulation.
Topics: AMP-Activated Protein Kinases; Animals; Bacterial Load; Cells, Cultured; Deoxyglucose; Disease Models, Animal; Fasting; Female; Humans; Interleukin-10; Interleukin-12; Listeriosis; Metabolome; Mice; Mice, Inbred BALB C; Myeloid Cells; Signal Transduction; TOR Serine-Threonine Kinases; Toll-Like Receptors
PubMed: 28742108
DOI: 10.1371/journal.pone.0180900 -
Virology Journal May 2023Increased glucose uptake and utilization via aerobic glycolysis are among the most prominent hallmarks of tumor cell metabolism. Accumulating evidence suggests that...
BACKGROUND
Increased glucose uptake and utilization via aerobic glycolysis are among the most prominent hallmarks of tumor cell metabolism. Accumulating evidence suggests that similar metabolic changes are also triggered in many virus-infected cells. Viral propagation, like highly proliferative tumor cells, increases the demand for energy and macromolecular synthesis, leading to high bioenergetic and biosynthetic requirements. Although significant progress has been made in understanding the metabolic changes induced by viruses, the interaction between host cell metabolism and arenavirus infection remains unclear. Our study sheds light on these processes during lymphocytic choriomeningitis virus (LCMV) infection, a model representative of the Arenaviridae family.
METHODS
The impact of LCMV on glucose metabolism in MRC-5 cells was studied using reverse transcription-quantitative PCR and biochemical assays. A focus-forming assay and western blot analysis were used to determine the effects of glucose deficiency and glycolysis inhibition on the production of infectious LCMV particles.
RESULTS
Despite changes in the expression of glucose transporters and glycolytic enzymes, LCMV infection did not result in increased glucose uptake or lactate excretion. Accordingly, depriving LCMV-infected cells of extracellular glucose or inhibiting lactate production had no impact on viral propagation. However, treatment with the commonly used glycolytic inhibitor 2-deoxy-D-glucose (2-DG) profoundly reduced the production of infectious LCMV particles. This effect of 2-DG was further shown to be the result of suppressed N-linked glycosylation of the viral glycoprotein.
CONCLUSIONS
Although our results showed that the LCMV life cycle is not dependent on glucose supply or utilization, they did confirm the importance of N-glycosylation of LCMV GP-C. 2-DG potently reduces LCMV propagation not by disrupting glycolytic flux but by inhibiting N-linked protein glycosylation. These findings highlight the potential for developing new, targeted antiviral therapies that could be relevant to a wider range of arenaviruses.
Topics: Humans; Lymphocytic choriomeningitis virus; Glycosylation; Glycoproteins; Lymphocytic Choriomeningitis; Deoxyglucose
PubMed: 37259080
DOI: 10.1186/s12985-023-02082-3 -
Journal of Immunology (Baltimore, Md. :... Oct 2021This report evaluates how HSV enters the brain to cause herpes simplex encephalitis following infection at a peripheral site. We demonstrate that encephalitis regularly...
This report evaluates how HSV enters the brain to cause herpes simplex encephalitis following infection at a peripheral site. We demonstrate that encephalitis regularly occurred when BALB/c mice were infected with HSV and treated daily with 2-deoxy-d-glucose (2DG), which inhibits glucose use via the glycolysis pathway. The outcome of infection in the trigeminal ganglion (TG), the site to which the virus spreads, replicates, and establishes latency, showed marked differences in viral and cellular events between treated and untreated animals. In control-untreated mice, the replicating virus was present only during early time points, whereas in 2DG recipients, replicating virus remained for the 9-d observation period. This outcome correlated with significantly reduced numbers of innate inflammatory cells as well as T cells in 2DG-treated animals. Moreover, T cells in the TG of treated animals were less activated and contained a smaller fraction of expressed IFN-γ production compared with untreated controls. The breakdown of latency was accelerated when cultures of TG cells taken from mice with established HSV latency were cultured in the presence of 2DG. Taken together, the results of both in vivo and in vitro investigations demonstrate that the overall effects of 2DG therapy impaired the protective effects of one or more inflammatory cell types in the TG that normally function to control productive infection and prevent spread of virus to the brain.
Topics: Animals; Brain; Cells, Cultured; Deoxyglucose; Encephalitis, Herpes Simplex; Glucose; Humans; Immunity, Innate; Interferon-gamma; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Simplexvirus; T-Lymphocytes; Virus Latency
PubMed: 34470854
DOI: 10.4049/jimmunol.2100453 -
Journal of Nuclear Medicine : Official... Jun 2023PET is a powerful molecular imaging technique that can provide functional information on living objects. However, the spatial resolution of PET imaging has been limited...
PET is a powerful molecular imaging technique that can provide functional information on living objects. However, the spatial resolution of PET imaging has been limited to around 1 mm, which makes it difficult to visualize mouse brain function in detail. Here, we report an ultrahigh-resolution small-animal PET scanner we developed that can provide a resolution approaching 0.6 mm to visualize mouse brain function with unprecedented detail. The ultrahigh-resolution small-animal PET scanner has an inner diameter of 52.5 mm and axial coverage of 51.5 mm. The scanner consists of 4 rings, each of which has 16 depth-of-interaction detectors. Each depth-of-interaction detector consists of a 3-layer staggered lutetium yttrium orthosilicate crystal array with a pitch of 1 mm and a 4 × 4 silicon photomultiplier array. The physical performance was evaluated in accordance with the National Electrical Manufacturers Association NU4 protocol. Spatial resolution was evaluated with phantoms of various resolutions. In vivo glucose metabolism imaging of the mouse brain was performed. Peak absolute sensitivity was 2.84% with an energy window of 400-600 keV. The 0.55-mm rod structure of a resolution phantom was resolved using an iterative algorithm. In vivo mouse brain imaging with F-FDG clearly identified the cortex, thalamus, and hypothalamus, which were barely distinguishable in a commercial preclinical PET scanner that we used for comparison. The ultrahigh-resolution small-animal PET scanner is a promising molecular imaging tool for neuroscience research using rodent models.
Topics: Mice; Animals; Positron-Emission Tomography; Fluorodeoxyglucose F18; Phantoms, Imaging; Neuroimaging; Equipment Design
PubMed: 36581375
DOI: 10.2967/jnumed.122.264433 -
Movement Disorders : Official Journal... Oct 2022Lewy body diseases (LBDs), which are pathologically defined as the presence of intraneuronal α-synuclein (α-Syn) inclusions called Lewy bodies, encompass Parkinson's...
BACKGROUND
Lewy body diseases (LBDs), which are pathologically defined as the presence of intraneuronal α-synuclein (α-Syn) inclusions called Lewy bodies, encompass Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies. Autopsy studies have shown that the olfactory bulb (OB) is one of the regions where Lewy pathology develops and initiates its spread in the brain.
OBJECTIVE
This study aims to clarify how Lewy pathology spreads from the OB and affects brain functions using nonhuman primates.
METHODS
We inoculated α-Syn preformed fibrils into the unilateral OBs of common marmosets (Callithrix jacchus) and performed pathological analyses, manganese-enhanced magnetic resonance imaging, and F-fluoro-2-deoxy-d-glucose positron emission tomography up to 6 months postinoculation.
RESULTS
Severe α-Syn pathology was observed within the olfactory pathway and limbic system, while mild α-Syn pathology was seen in a wide range of brain regions, including the substantia nigra pars compacta, locus coeruleus, and even dorsal motor nucleus of the vagus nerve. The brain imaging analyses showed reduction in volume of the OB and progressive glucose hypometabolism in widespread brain regions, including the occipital lobe, and extended beyond the pathologically affected regions.
CONCLUSIONS
We generated a novel nonhuman primate LBD model with α-Syn propagation from the OB. This model suggests that α-Syn propagation from the OB is related to OB atrophy and cerebral glucose hypometabolism in LBDs. © 2022 International Parkinson and Movement Disorder Society.
Topics: Animals; Callithrix; Deoxyglucose; Glucose; Lewy Body Disease; Manganese; Olfactory Bulb; Parkinson Disease; alpha-Synuclein
PubMed: 35989519
DOI: 10.1002/mds.29161 -
Cell Reports Nov 2017Aerobic glycolysis, also known as the Warburg effect, is a hallmark of cancerous tissues. Despite its importance in cancer development, our understanding of mechanisms...
Aerobic glycolysis, also known as the Warburg effect, is a hallmark of cancerous tissues. Despite its importance in cancer development, our understanding of mechanisms driving this form of metabolic reprogramming is incomplete. We report here an analysis of colorectal cancer cells engineered to carry a single point mutation in the active site of the Mediator-associated kinase CDK8, creating hypomorphic alleles sensitive to bulky ATP analogs. Transcriptome analysis revealed that CDK8 kinase activity is required for the expression of many components of the glycolytic cascade. CDK8 inhibition impairs glucose transporter expression, glucose uptake, glycolytic capacity and reserve, as well as cell proliferation and anchorage-independent growth, both in normoxia and hypoxia. Importantly, CDK8 impairment sensitizes cells to pharmacological glycolysis inhibition, a result reproduced with Senexin A, a dual inhibitor of CDK8/CDK19. Altogether, these results contribute to our understanding of CDK8 as an oncogene, and they justify investigations to target CDK8 in highly glycolytic tumors.
Topics: Biomarkers, Tumor; Cell Hypoxia; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase 8; Cyclin-Dependent Kinases; DNA-Binding Proteins; Deoxyglucose; Down-Regulation; Gene Editing; Glucose Transporter Type 3; Glycolysis; HCT116 Cells; Hexokinase; Humans; Mutagenesis, Site-Directed; Phosphopyruvate Hydratase; Protein Kinase Inhibitors; Purines; Transcriptome; Tumor Suppressor Proteins
PubMed: 29117556
DOI: 10.1016/j.celrep.2017.10.058 -
European Journal of Immunology Sep 2015Cellular metabolism is emerging as a key determinant of T-lymphocyte differentiation and function. While this new paradigm has been primarily characterized in murine...
Cellular metabolism is emerging as a key determinant of T-lymphocyte differentiation and function. While this new paradigm has been primarily characterized in murine systems, research is now characterizing a role for different aspects of cellular metabolism in controlling human T-lymphocyte biology. In this issue of the European Journal of Immunology, Renner et al. [Eur. J. Immunol. 2015. 45: 2504-2516] analyze the glycolytic and mitochondrial activity of activated human CD4(+) and CD8(+) T cells, and correlate it to T-cell function. The authors show that although neither glucose deprivation nor mitochondrial restriction affects cytokine production, the glycolytic inhibitor 2-deoxyglucose severely affects T-cell function.
Topics: CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Deoxyglucose; Glucose; Humans; Mitochondria; T-Lymphocyte Subsets
PubMed: 26256443
DOI: 10.1002/eji.201545885 -
The Review of Diabetic Studies : RDS Jun 20221,5-anhydroglucitol (1,5-AG) is a biomarker of acute hyperglycemia in diabetology and also in cardiodiabetology. It is used to monitor fluctuating glucose levels. 1,5-AG...
1,5-anhydroglucitol (1,5-AG) is a biomarker of acute hyperglycemia in diabetology and also in cardiodiabetology. It is used to monitor fluctuating glucose levels. 1,5-AG is a monosaccharide that is biochemically similar to D-glucose and originates from the nutrition. The presence of 1,5-AG in blood and tissue is nearly constant due to reabsorption in the renal proximal tubule. In acute hyperglycemia, renal reabsorption is inhibited by glucose and 1,5- AG is excreted in the urine, while its serum level decreases rapidly. 1,5-AG reflects glucose excursions over 1-3 days to 2 weeks. In this regard, low levels of serum 1,5-AG can be a clinical marker of short- term glycemic derangements such as postprandial hyperglycemia, which is an important risk factor for the pathogenesis of coronary artery disease (CAD) as low levels of 1,5-AG reflect severe plaque calcification in CAD and correlate with high-density lipoprotein cholesterol (HDL-C) levels. For these reasons, 1,5-AG may also be a marker for atherosclerosis; in fact an even better marker than HbA1c or fructosamine which are normally used. 1,5-AG may also be a predictor of cardiovascular disease, left ventricular dysfunction after acute coronary syndrome (ACS), and mortality after ACS. This articles reviews the current knowledge on 1,5-AG related to its use as predictor for cardiovascular events.
Topics: Acute Coronary Syndrome; Biomarkers; Blood Glucose; Coronary Artery Disease; Deoxyglucose; Glycated Hemoglobin; Humans; Hyperglycemia
PubMed: 35831937
DOI: 10.1900/RDS.2022.18.68 -
Journal of Neuroscience Research Nov 2017Succinylation of proteins is widespread, modifies both the charge and size of the molecules, and can alter their function. For example, liver mitochondrial proteins have...
Succinylation of proteins is widespread, modifies both the charge and size of the molecules, and can alter their function. For example, liver mitochondrial proteins have 1,190 unique succinylation sites representing multiple metabolic pathways. Succinylation is sensitive to both increases and decreases of the NAD -dependent desuccinylase, SIRT5. Although the succinyl group for succinylation is derived from metabolism, the effects of systematic variation of metabolism on mitochondrial succinylation are not known. Changes in succinylation of mitochondrial proteins following variations in metabolism were compared against the mitochondrial redox state as estimated by the mitochondrial NAD /NADH ratio using fluorescent probes. The ratio was decreased by reduced glycolysis and/or glutathione depletion (iodoacetic acid; 2-deoxyglucose), depressed tricarboxylic acid cycle activity (carboxyethyl ester of succinyl phosphonate), and impairment of electron transport (antimycin) or ATP synthase (oligomycin), while uncouplers of oxidative phosphorylation (carbonyl cyanide m-chlorophenyl hydrazine or tyrphostin) increased the NAD /NADH ratio. All of the conditions decreased succinylation. In contrast, reducing the oxygen from 20% to 2.4% increased succinylation. The results demonstrate that succinylation varies with metabolic states, is not correlated to the mitochondrial NAD /NADH ratio, and may help coordinate the response to metabolic challenge.
Topics: Animals; Cell Line, Tumor; Deoxyglucose; Mice; Mitochondrial Proteins; NAD; Organophosphonates; Oxidation-Reduction; Oxidative Phosphorylation; Succinates; Succinic Acid
PubMed: 28631845
DOI: 10.1002/jnr.24103 -
Cell Reports Oct 2015Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic...
Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG), the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON). Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.
Topics: Allografts; Animals; CD8-Positive T-Lymphocytes; Cells, Cultured; Deoxyglucose; Diazooxonorleucine; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Glutamine; Glycolysis; Graft Rejection; Heart Transplantation; Metformin; Mice; Mice, Inbred BALB C; Mice, Transgenic; Phosphorylation; T-Lymphocytes, Regulatory
PubMed: 26489460
DOI: 10.1016/j.celrep.2015.09.036