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1.
bioRxiv ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39314273

RESUMEN

Emerging data have highlighted a correlation between microbiome composition and cancer immunotherapy outcome. While commensal bacteria and their metabolites are known to modulate the host environment, contradictory effects and a lack of mechanistic understanding impede the translation of microbiome-based therapies into the clinic. In this study, we demonstrate that abundance of the commensal metabolite pentanoate is predictive for survival of chimeric antigen receptor (CAR) T cell patients in two independent cohorts. Its implementation in the CAR T cell manufacturing workflow overcomes solid tumor microenvironments in immunocompetent cancer models by hijacking the epigenetic-metabolic crosstalk, reducing exhaustion and promoting naive-like differentiation. While synergy of clinically relevant drugs mimicked the phenotype of pentanoate-engineered CAR T cells in vitro, in vivo challenge showed inferior tumor control. Metabolic tracing of 13C-pentanoate revealed citrate generation in the TCA cycle via the acetyl- and succinyl-CoA entry points as a unique feature of the C5 aliphatic chain. Inhibition of the ATP-citrate lyase, which links metabolic output and histone acetylation, led to accumulation of pentanoate-derived citrate from the succinyl-CoA route and decreased functionality of SCFA-engineered CAR T cells. Our data demonstrate that microbial metabolites are incorporated as epigenetic imprints and implementation into CAR T cell production might serve as embodiment of the microbiome-host axis benefits for clinical applications.

3.
Nat Neurosci ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251890

RESUMEN

Brain function requires a constant supply of glucose. However, the brain has no known energy stores, except for glycogen granules in astrocytes. In the present study, we report that continuous oligodendroglial lipid metabolism provides an energy reserve in white matter tracts. In the isolated optic nerve from young adult mice of both sexes, oligodendrocytes survive glucose deprivation better than astrocytes. Under low glucose, both axonal ATP levels and action potentials become dependent on fatty acid ß-oxidation. Importantly, ongoing oligodendroglial lipid degradation feeds rapidly into white matter energy metabolism. Although not supporting high-frequency spiking, fatty acid ß-oxidation in mitochondria and oligodendroglial peroxisomes protects axons from conduction blocks when glucose is limiting. Disruption of the glucose transporter GLUT1 expression in oligodendrocytes of adult mice perturbs myelin homeostasis in vivo and causes gradual demyelination without behavioral signs. This further suggests that the imbalance of myelin synthesis and degradation can underlie myelin thinning in aging and disease.

4.
J Neuroinflammation ; 21(1): 207, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164713

RESUMEN

Despite advances in antimicrobial and anti-inflammatory treatment, inflammation and its consequences remain a major challenge in the field of medicine. Inflammatory reactions can lead to life-threatening conditions such as septic shock, while chronic inflammation has the potential to worsen the condition of body tissues and ultimately lead to significant impairment of their functionality. Although the central nervous system has long been considered immune privileged to peripheral immune responses, recent research has shown that strong immune responses in the periphery also affect the brain, leading to reactive microglia, which belong to the innate immune system and reside in the brain, and neuroinflammation. The inflammatory response is primarily a protective mechanism to defend against pathogens and tissue damage. However, excessive and chronic inflammation can have negative effects on neuronal structure and function. Neuroinflammation underlies the pathogenesis of many neurological and neurodegenerative diseases and can accelerate their progression. Consequently, targeting inflammatory signaling pathways offers potential therapeutic strategies for various neuropathological conditions, particularly Parkinson's and Alzheimer's disease, by curbing inflammation. Here the blood-brain barrier is a major hurdle for potential therapeutic strategies, therefore it would be highly advantageous to foster and utilize brain innate anti-inflammatory mechanisms. The tricarboxylic acid cycle-derived metabolite itaconate is highly upregulated in activated macrophages and has been shown to act as an immunomodulator with anti-inflammatory and antimicrobial functions. Mesaconate, an isomer of itaconate, similarly reduces the inflammatory response in macrophages. Nevertheless, most studies have focused on its esterified forms and its peripheral effects, while its influence on the CNS remained largely unexplored. Therefore, this study investigated the immunomodulatory and therapeutic potential of endogenously synthesized itaconate and its isomer mesaconate in lipopolysaccharide (LPS)-induced neuroinflammatory processes. Our results show that both itaconate and mesaconate reduce LPS-induced neuroinflammation, as evidenced by lower levels of inflammatory mediators, reduced microglial reactivity and a rescue of synaptic plasticity, the cellular correlate of learning and memory processes in the brain. Overall, this study emphasizes that both itaconate and mesaconate have therapeutic potential for neuroinflammatory processes in the brain and are of remarkable importance due to their endogenous origin and production, which usually leads to high tolerance.


Asunto(s)
Lipopolisacáridos , Enfermedades Neuroinflamatorias , Succinatos , Animales , Succinatos/farmacología , Succinatos/uso terapéutico , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/inducido químicamente , Enfermedades Neuroinflamatorias/inmunología , Lipopolisacáridos/toxicidad , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/inmunología , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Masculino , Ratones Endogámicos C57BL
5.
Genes Nutr ; 19(1): 18, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210266

RESUMEN

This study aimed to identify markers of postprandial dysglycemia in the blood of self-described healthy individuals using dry blood spots (DBS) as a sampling strategy. A total of 54 volunteers, including 31 women, participated in a dietary challenge. They consumed a high-fat, high-sugar mixed meal and underwent multiple blood sampling over the course of 150 min to track their postprandial responses. Blood glucose levels were monitored with a portable glucometer and individuals were classified into two groups based on the glucose area under the curve (AUC): High-AUC (H-AUC) and Low-AUC (L-AUC). DBS sampling was performed at the same time points as the assessment of glycemia using Whatman 903 Protein Saver filter paper. A gas chromatography-mass spectrometry-based metabolite profiling was conducted in the DBS samples to assess postprandial changes in blood metabolome. Higher concentrations of metabolites associated with insulin resistance were observed in individuals from the H-AUC group, including sugars and sugar-derived products such as fructose and threonic acid, as well as organic acids and fatty acids such as succinate and stearic acid. Several metabolites detected in the GC-MS analysis remained unidentified, indicating that other markers of hyperglycemia remain to be discovered in DBS. Based on these observations, we demonstrated that the use of DBS as a non-invasive and inexpensive sampling tool allows the identification of metabolites markers of dysglycemia in the postprandial period.

6.
Nat Immunol ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198632

RESUMEN

The efficacy of antitumor immunity is associated with the metabolic state of cytotoxic T cells, which is sensitive to the tumor microenvironment. Whether ionic signals affect adaptive antitumor immune responses is unclear. In the present study, we show that there is an enrichment of sodium in solid tumors from patients with breast cancer. Sodium chloride (NaCl) enhances the activation state and effector functions of human CD8+ T cells, which is associated with enhanced metabolic fitness. These NaCl-induced effects translate into increased tumor cell killing in vitro and in vivo. Mechanistically, NaCl-induced changes in CD8+ T cells are linked to sodium-induced upregulation of Na+/K+-ATPase activity, followed by membrane hyperpolarization, which magnifies the electromotive force for T cell receptor (TCR)-induced calcium influx and downstream TCR signaling. We therefore propose that NaCl is a positive regulator of acute antitumor immunity that might be modulated for ex vivo conditioning of therapeutic T cells, such as CAR T cells.

7.
Nat Commun ; 15(1): 6438, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085210

RESUMEN

Innate immune responses are linked to key metabolic pathways, yet the proximal signaling events that connect these systems remain poorly understood. Here we show that phosphofructokinase 1, liver type (PFKL), a rate-limiting enzyme of glycolysis, is phosphorylated at Ser775 in macrophages following several innate stimuli. This phosphorylation increases the catalytic activity of PFKL, as shown by biochemical assays and glycolysis monitoring in cells expressing phosphorylation-defective PFKL variants. Using a genetic mouse model in which PFKL Ser775 phosphorylation cannot take place, we observe that upon activation, glycolysis in macrophages is lower than in the same cell population of wild-type animals. Consistent with their higher glycolytic activity, wild-type cells have higher levels of HIF1α and IL-1ß than PfklS775A/S775A after LPS treatment. In an in vivo inflammation model, PfklS775A/S775A mice show reduced levels of MCP-1 and IL-1ß. Our study thus identifies a molecular link between innate immune activation and early induction of glycolysis.


Asunto(s)
Glucólisis , Subunidad alfa del Factor 1 Inducible por Hipoxia , Inmunidad Innata , Interleucina-1beta , Macrófagos , Animales , Macrófagos/metabolismo , Macrófagos/inmunología , Ratones , Fosforilación , Interleucina-1beta/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Receptores de Reconocimiento de Patrones/metabolismo , Receptores de Reconocimiento de Patrones/genética , Fosfofructoquinasa-1/metabolismo , Fosfofructoquinasa-1/genética , Lipopolisacáridos/farmacología , Ratones Endogámicos C57BL , Humanos , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Inflamación/metabolismo , Masculino , Reprogramación Metabólica
8.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167312, 2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-38901649

RESUMEN

Epithelial ovarian cancer (EOC) is highly lethal due to its unique metastatic characteristics. EOC spheroids enter a non-proliferative state, with hypoxic cores and reduced oncogenic signaling, all of which contribute to tumour dormancy during metastasis. We investigated the metabolomic states of EOC cells progressing through the three steps to metastasis. Metabolomes of adherent, spheroid, and re-adherent cells were validated by isotopic metabolic flux analysis and mitochondrial functional assays to identify metabolic pathways that were previously unknown to promote EOC metastasis. Although spheroids were thought to exist in a dormant state, metabolomic analysis revealed an unexpected upregulation of energy production pathways in spheroids, accompanied by increased abundance of tricarboxylic acid (TCA) cycle and electron transport chain proteins. Tracing of 13C-labelled glucose and glutamine showed increased pyruvate carboxylation and decreased glutamine anaplerosis in spheroids. Increased reductive carboxylation suggests spheroids adjust redox homeostasis by shuttling cytosolic NADPH into mitochondria via isocitrate dehydrogenase. Indeed, we observed spheroids have increased respiratory capacity and mitochondrial ATP production. Relative to adherent cells, spheroids reduced serine consumption and metabolism, processes which were reversed upon spheroid re-adherence. The data reveal a distinct metabolism in EOC spheroids that enhances energy production by the mitochondria while maintaining a dormant state with respect to growth and proliferation. The findings advance our understanding of EOC metastasis and identify the TCA cycle and mitochondrional activity as novel targets to disrupt EOC metastasis, providing new approaches to treat advanced disease.


Asunto(s)
Carcinoma Epitelial de Ovario , Ciclo del Ácido Cítrico , Mitocondrias , Metástasis de la Neoplasia , Neoplasias Ováricas , Esferoides Celulares , Humanos , Carcinoma Epitelial de Ovario/metabolismo , Carcinoma Epitelial de Ovario/patología , Femenino , Esferoides Celulares/metabolismo , Esferoides Celulares/patología , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Mitocondrias/metabolismo , Mitocondrias/patología , Línea Celular Tumoral , Glutamina/metabolismo , Metabolismo Energético , Metabolómica , Glucosa/metabolismo
9.
Mol Metab ; 85: 101963, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38821174

RESUMEN

OBJECTIVE: The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor regulating xenobiotic responses as well as physiological metabolism. Dietary AhR ligands activate the AhR signaling axis, whereas AhR activation is negatively regulated by the AhR repressor (AhRR). While AhR-deficient mice are known to be resistant to diet-induced obesity (DIO), the influence of the AhRR on DIO has not been assessed so far. METHODS: In this study, we analyzed AhRR-/- mice and mice with a conditional deletion of either AhRR or AhR in myeloid cells under conditions of DIO and after supplementation of dietary AhR ligands. Moreover, macrophage metabolism was assessed using Seahorse Mito Stress Test and ROS assays as well as transcriptomic analysis. RESULTS: We demonstrate that global AhRR deficiency leads to a robust, but not as profound protection from DIO and hepatosteatosis as AhR deficiency. Under conditions of DIO, AhRR-/- mice did not accumulate TCA cycle intermediates in the circulation in contrast to wild-type (WT) mice, indicating protection from metabolic dysfunction. This effect could be mimicked by dietary supplementation of AhR ligands in WT mice. Because of the predominant expression of the AhRR in myeloid cells, AhRR-deficient macrophages were analyzed for changes in metabolism and showed major metabolic alterations regarding oxidative phosphorylation and mitochondrial activity. Unbiased transcriptomic analysis revealed increased expression of genes involved in de novo lipogenesis and mitochondrial biogenesis. Mice with a genetic deficiency of the AhRR in myeloid cells did not show alterations in weight gain after high fat diet (HFD) but demonstrated ameliorated liver damage compared to control mice. Further, deficiency of the AhR in myeloid cells also did not affect weight gain but led to enhanced liver damage and adipose tissue fibrosis compared to controls. CONCLUSIONS: AhRR-deficient mice are resistant to diet-induced metabolic syndrome. Although conditional ablation of either the AhR or AhRR in myeloid cells did not recapitulate the phenotype of the global knockout, our findings suggest that enhanced AhR signaling in myeloid cells deficient for AhRR protects from diet-induced liver damage and fibrosis, whereas myeloid cell-specific AhR deficiency is detrimental.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Dieta Alta en Grasa , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad , Receptores de Hidrocarburo de Aril , Animales , Receptores de Hidrocarburo de Aril/metabolismo , Receptores de Hidrocarburo de Aril/genética , Obesidad/metabolismo , Ratones , Dieta Alta en Grasa/efectos adversos , Masculino , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Macrófagos/metabolismo , Células Mieloides/metabolismo , Fibrosis/metabolismo , Hígado/metabolismo , Transducción de Señal
10.
Sci Data ; 11(1): 524, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778016

RESUMEN

Datasets consist of measurement data and metadata. Metadata provides context, essential for understanding and (re-)using data. Various metadata standards exist for different methods, systems and contexts. However, relevant information resides at differing stages across the data-lifecycle. Often, this information is defined and standardized only at publication stage, which can lead to data loss and workload increase. In this study, we developed Metadatasheet, a metadata standard based on interviews with members of two biomedical consortia and systematic screening of data repositories. It aligns with the data-lifecycle allowing synchronous metadata recording within Microsoft Excel, a widespread data recording software. Additionally, we provide an implementation, the Metadata Workbook, that offers user-friendly features like automation, dynamic adaption, metadata integrity checks, and export options for various metadata standards. By design and due to its extensive documentation, the proposed metadata standard simplifies recording and structuring of metadata for biomedical scientists, promoting practicality and convenience in data management. This framework can accelerate scientific progress by enhancing collaboration and knowledge transfer throughout the intermediate steps of data creation.


Asunto(s)
Manejo de Datos , Metadatos , Investigación Biomédica , Manejo de Datos/normas , Metadatos/normas , Programas Informáticos
11.
Front Oncol ; 14: 1286896, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450189

RESUMEN

Background: Cachexia is a body wasting syndrome that significantly affects well-being and prognosis of cancer patients, without effective treatment. Serum metabolites take part in pathophysiological processes of cancer cachexia, but apart from altered levels of select serum metabolites, little is known on the global changes of the overall serum metabolome, which represents a functional readout of the whole-body metabolic state. Here, we aimed to comprehensively characterize serum metabolite alterations and analyze associated pathways in cachectic cancer patients to gain new insights that could help instruct strategies for novel interventions of greater clinical benefit. Methods: Serum was sampled from 120 metastatic cancer patients (stage UICC IV). Patients were grouped as cachectic or non-cachectic according to the criteria for cancer cachexia agreed upon international consensus (main criterium: weight loss adjusted to body mass index). Samples were pooled by cachexia phenotype and assayed using non-targeted gas chromatography-mass spectrometry (GC-MS). Normalized metabolite levels were compared using t-test (p < 0.05, adjusted for false discovery rate) and partial least squares discriminant analysis (PLS-DA). Machine-learning models were applied to identify metabolite signatures for separating cachexia states. Significant metabolites underwent MetaboAnalyst 5.0 pathway analysis. Results: Comparative analyses included 78 cachectic and 42 non-cachectic patients. Cachectic patients exhibited 19 annotable, significantly elevated (including glucose and fructose) or decreased (mostly amino acids) metabolites associating with aminoacyl-tRNA, glutathione and amino acid metabolism pathways. PLS-DA showed distinct clusters (accuracy: 85.6%), and machine-learning models identified metabolic signatures for separating cachectic states (accuracy: 83.2%; area under ROC: 88.0%). We newly identified altered blood levels of erythronic acid and glucuronic acid in human cancer cachexia, potentially linked to pentose-phosphate and detoxification pathways. Conclusion: We found both known and yet unknown serum metabolite and metabolic pathway alterations in cachectic cancer patients that collectively support a whole-body metabolic state with impaired detoxification capability, altered glucose and fructose metabolism, and substrate supply for increased and/or distinct metabolic needs of cachexia-associated tumors. These findings together imply vulnerabilities, dependencies and targets for novel interventions that have potential to make a significant impact on future research in an important field of cancer patient care.

12.
J Immunol ; 212(1): 7-11, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38038390

RESUMEN

The 2'3'-cyclic GMP-AMP (cGAMP) synthase (cGAS)-stimulator of IFN genes (STING) pathway can sense infection and cellular stress by detecting cytosolic DNA. Upon ligand binding, cGAS produces the cyclic dinucleotide messenger cGAMP, which triggers its receptor STING. Active STING initiates gene transcription through the transcription factors IFN regulatory factor 3 (IRF3) and NF-κB and induces autophagy, but whether STING can cause changes in the metabolism of macrophages is unknown. In this study, we report that STING signaling activates ATP-citrate lyase (ACLY) by phosphorylation in human macrophages. Using genetic and pharmacologic perturbation, we show that STING targets ACLY via its prime downstream signaling effector TANK (TRAF family member-associated NF-κB activator)-binding kinase 1 (TBK1). We further identify that TBK1 alters cellular metabolism upon cGAMP treatment. Our results suggest that STING-mediated metabolic reprogramming adjusts the cellular response to DNA sensing in addition to transcription factor activation and autophagy induction.


Asunto(s)
FN-kappa B , Proteínas Serina-Treonina Quinasas , Humanos , ATP Citrato (pro-S)-Liasa/metabolismo , ADN , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/metabolismo , Proteínas de la Membrana/metabolismo , FN-kappa B/metabolismo , Nucleotidiltransferasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo
13.
Nat Commun ; 14(1): 7674, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996418

RESUMEN

Sporadic Parkinson's Disease (sPD) is a progressive neurodegenerative disorder caused by multiple genetic and environmental factors. Mitochondrial dysfunction is one contributing factor, but its role at different stages of disease progression is not fully understood. Here, we showed that neural precursor cells and dopaminergic neurons derived from induced pluripotent stem cells (hiPSCs) from sPD patients exhibited a hypometabolism. Further analysis based on transcriptomics, proteomics, and metabolomics identified the citric acid cycle, specifically the α-ketoglutarate dehydrogenase complex (OGDHC), as bottleneck in sPD metabolism. A follow-up study of the patients approximately 10 years after initial biopsy demonstrated a correlation between OGDHC activity in our cellular model and the disease progression. In addition, the alterations in cellular metabolism observed in our cellular model were restored by interfering with the enhanced SHH signal transduction in sPD. Thus, inhibiting overactive SHH signaling may have potential as neuroprotective therapy during early stages of sPD.


Asunto(s)
Células-Madre Neurales , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/metabolismo , Células-Madre Neurales/metabolismo , Estudios de Seguimiento , Neuronas Dopaminérgicas/metabolismo , Progresión de la Enfermedad
14.
Genome Biol ; 24(1): 265, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996937

RESUMEN

BACKGROUND: "Red tides" are harmful algal blooms caused by dinoflagellate microalgae that accumulate toxins lethal to other organisms, including humans via consumption of contaminated seafood. These algal blooms are driven by a combination of environmental factors including nutrient enrichment, particularly in warm waters, and are increasingly frequent. The molecular, regulatory, and evolutionary mechanisms that underlie the heat stress response in these harmful bloom-forming algal species remain little understood, due in part to the limited genomic resources from dinoflagellates, complicated by the large sizes of genomes, exhibiting features atypical of eukaryotes. RESULTS: We present the de novo assembled genome (~ 4.75 Gbp with 85,849 protein-coding genes), transcriptome, proteome, and metabolome from Prorocentrum cordatum, a globally abundant, bloom-forming dinoflagellate. Using axenic algal cultures, we study the molecular mechanisms that underpin the algal response to heat stress, which is relevant to current ocean warming trends. We present the first evidence of a complementary interplay between RNA editing and exon usage that regulates the expression and functional diversity of biomolecules, reflected by reduction in photosynthesis, central metabolism, and protein synthesis. These results reveal genomic signatures and post-transcriptional regulation for the first time in a pelagic dinoflagellate. CONCLUSIONS: Our multi-omics analyses uncover the molecular response to heat stress in an important bloom-forming algal species, which is driven by complex gene structures in a large, high-G+C genome, combined with multi-level transcriptional regulation. The dynamics and interplay of molecular regulatory mechanisms may explain in part how dinoflagellates diversified to become some of the most ecologically successful organisms on Earth.


Asunto(s)
Dinoflagelados , Floraciones de Algas Nocivas , Humanos , Dinoflagelados/genética , Multiómica , Genómica , Respuesta al Choque Térmico
15.
Biomedicines ; 11(10)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37893215

RESUMEN

Using an untargeted stable isotope-assisted metabolomics approach, we identify erythronate as a metabolite that accumulates in several human cancer cell lines. Erythronate has been reported to be a detoxification product derived from off-target glycolytic metabolism. We use chemical inhibitors and genetic silencing to define the pentose phosphate pathway intermediate erythrose 4-phosphate (E4P) as the starting substrate for erythronate production. However, following enzyme assay-coupled protein fractionation and subsequent proteomics analysis, we identify aldehyde dehydrogenase 1A1 (ALDH1A1) as the predominant contributor to erythrose oxidation to erythronate in cell extracts. Through modulating ALDH1A1 expression in cancer cell lines, we provide additional support. We hence describe a possible alternative route to erythronate production involving the dephosphorylation of E4P to form erythrose, followed by its oxidation by ALDH1A1. Finally, we measure increased erythronate concentrations in tumors relative to adjacent normal tissues from lung cancer patients. These findings suggest the accumulation of erythronate to be an example of metabolic reprogramming in cancer cells, raising the possibility that elevated levels of erythronate may serve as a biomarker of certain types of cancer.

16.
Environ Int ; 179: 108169, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37688811

RESUMEN

Epidemiological studies identified air pollution as one of the prime causes for human morbidity and mortality, due to harmful effects mainly on the cardiovascular and respiratory systems. Damage to the lung leads to several severe diseases such as fibrosis, chronic obstructive pulmonary disease and cancer. Noxious environmental aerosols are comprised of a gas and particulate phase representing highly complex chemical mixtures composed of myriads of compounds. Although some critical pollutants, foremost particulate matter (PM), could be linked to adverse health effects, a comprehensive understanding of relevant biological mechanisms and detrimental aerosol constituents is still lacking. Here, we employed a systems toxicology approach focusing on wood combustion, an important source for air pollution, and demonstrate a key role of the gas phase, specifically carbonyls, in driving adverse effects. Transcriptional profiling and biochemical analysis of human lung cells exposed at the air-liquid-interface determined DNA damage and stress response, as well as perturbation of cellular metabolism, as major key events. Connectivity mapping revealed a high similarity of gene expression signatures induced by wood smoke and agents prompting DNA-protein crosslinks (DPCs). Indeed, various gaseous aldehydes were detected in wood smoke, which promote DPCs, initiate similar genomic responses and are responsible for DNA damage provoked by wood smoke. Hence, systems toxicology enables the discovery of critical constituents of complex mixtures i.e. aerosols and highlights the role of carbonyls on top of particulate matter as an important health hazard.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Gases , Humanos , Madera , Aerosoles y Gotitas Respiratorias , Aldehídos , Material Particulado/toxicidad , Humo/efectos adversos
17.
Redox Biol ; 67: 102878, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37703668

RESUMEN

Cruciferous-rich diets, particularly broccoli, have been associated with reduced risk of developing cancers of various sites, cardiovascular disease and type-2 diabetes. Sulforaphane (SF), a sulfur-containing broccoli-derived metabolite, has been identified as the major bioactive compound mediating these health benefits. Sulforaphane is a potent dietary activator of the transcription factor Nuclear factor erythroid-like 2 (NRF2), the master regulator of antioxidant cell capacity responsible for inducing cytoprotective genes, but its role in glucose homeostasis remains unclear. In this study, we set to test the hypothesis that SF regulates glucose metabolism and ameliorates glucose overload and its resulting oxidative stress by inducing NRF2 in human hepatoma HepG2 cells. HepG2 cells were exposed to varying glucose concentrations: basal (5.5 mM) and high glucose (25 mM), in the presence of physiological concentrations of SF (10 µM). SF upregulated the expression of glutathione (GSH) biosynthetic genes and significantly increased levels of reduced GSH. Labelled glucose and glutamine experiments to measure metabolic fluxes identified that SF increased intracellular utilisation of glycine and glutamate by redirecting the latter away from the TCA cycle and increased the import of cysteine from the media, likely to support glutathione synthesis. Furthermore, SF altered pathways generating NADPH, the necessary cofactor for oxidoreductase reactions, namely pentose phosphate pathway and 1C-metabolism, leading to the redirection of glucose away from glycolysis and towards PPP and of methionine towards methylation substrates. Finally, transcriptomic and targeted metabolomics LC-MS analysis of NRF2-KD HepG2 cells generated using CRISPR-Cas9 genome editing revealed that the above metabolic effects are mediated through NRF2. These results suggest that the antioxidant properties of cruciferous diets are intricately connected to their metabolic benefits.


Asunto(s)
Antioxidantes , Factor 2 Relacionado con NF-E2 , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Isotiocianatos/farmacología , Estrés Oxidativo , Glutatión/metabolismo , Homeostasis , Glucosa
18.
EMBO Rep ; 24(9): e57372, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37497662

RESUMEN

How cells coordinate their metabolism with division determines the rate of cell proliferation. Dynamic patterns of metabolite synthesis during the cell cycle are unexplored. We report the first isotope tracing analysis in synchronous, growing budding yeast cells. Synthesis of leucine, a branched-chain amino acid (BCAA), increases through the G1 phase of the cell cycle, peaking later during DNA replication. Cells lacking Bat1, a mitochondrial aminotransferase that synthesizes BCAAs, grow slower, are smaller, and are delayed in the G1 phase, phenocopying cells in which the growth-promoting kinase complex TORC1 is moderately inhibited. Loss of Bat1 lowers the levels of BCAAs and reduces TORC1 activity. Exogenous provision of valine and, to a lesser extent, leucine to cells lacking Bat1 promotes cell division. Valine addition also increases TORC1 activity. In wild-type cells, TORC1 activity is dynamic in the cell cycle, starting low in early G1 but increasing later in the cell cycle. These results suggest a link between BCAA synthesis from glucose to TORC1 activation in the G1 phase of the cell cycle.


Asunto(s)
Aminoácidos , Saccharomyces cerevisiae , Ciclo Celular , Aminoácidos/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/metabolismo , Leucina/biosíntesis , Glucosa/metabolismo , Fase G1
19.
Metabolites ; 13(7)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37512541

RESUMEN

Legionella pneumophila (Lp) is a common etiological agent of bacterial pneumonia that causes Legionnaires' disease (LD). The bacterial membrane-associated virulence factor macrophage infectivity potentiator (Mip) exhibits peptidyl-prolyl-cis/trans-isomerase (PPIase) activity and contributes to the intra- and extracellular pathogenicity of Lp. Though Mip influences disease outcome, little is known about the metabolic consequences of altered Mip activity during infections. Here, we established a metabolic workflow and applied mass spectrometry approaches to decipher how Mip activity influences metabolism and pathogenicity. Impaired Mip activity in genetically engineered Lp strains decreases intracellular replication in cellular infection assays, confirming the contribution of Mip for Lp pathogenicity. We observed that genetic and chemical alteration of Mip using the PPIase inhibitors rapamycin and FK506 induces metabolic reprogramming in Lp, specifically branched-chain amino acid (BCAA) metabolism. Rapamycin also inhibits PPIase activity of mammalian FK506 binding proteins, and we observed that rapamycin induces a distinct metabolic signature in human macrophages compared to bacteria, suggesting potential involvement of Mip in normal bacteria and in infection. Our metabolic studies link Mip to alterations in BCAA metabolism and may help to decipher novel disease mechanisms associated with LD.

20.
Metabolites ; 13(5)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37233706

RESUMEN

Untargeted metabolomics is an important tool in studying health and disease and is employed in fields such as biomarker discovery and drug development, as well as precision medicine. Although significant technical advances were made in the field of mass-spectrometry driven metabolomics, instrumental drifts, such as fluctuations in retention time and signal intensity, remain a challenge, particularly in large untargeted metabolomics studies. Therefore, it is crucial to consider these variations during data processing to ensure high-quality data. Here, we will provide recommendations for an optimal data processing workflow using intrastudy quality control (QC) samples that identifies errors resulting from instrumental drifts, such as shifts in retention time and metabolite intensities. Furthermore, we provide an in-depth comparison of the performance of three popular batch-effect correction methods of different complexity. By using different evaluation metrics based on QC samples and a machine learning approach based on biological samples, the performance of the batch-effect correction methods were evaluated. Here, the method TIGER demonstrated the overall best performance by reducing the relative standard deviation of the QCs and dispersion-ratio the most, as well as demonstrating the highest area under the receiver operating characteristic with three different probabilistic classifiers (Logistic regression, Random Forest, and Support Vector Machine). In summary, our recommendations will help to generate high-quality data that are suitable for further downstream processing, leading to more accurate and meaningful insights into the underlying biological processes.

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