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Antiviral signaling, immune response and cell metabolism are dysregulated by SARS-CoV-2, the causative agent of COVID-19. Here, we show that SARS-CoV-2 accessory proteins ORF3a, ORF9b, ORF9c and ORF10 induce a significant mitochondrial and metabolic reprogramming in A549 lung epithelial cells. While ORF9b, ORF9c and ORF10 induced largely overlapping transcriptomes, ORF3a induced a distinct transcriptome, including the downregulation of numerous genes with critical roles in mitochondrial function and morphology. On the other hand, all four ORFs altered mitochondrial dynamics and function, but only ORF3a and ORF9c induced a marked alteration in mitochondrial cristae structure. Genome-Scale Metabolic Models identified both metabolic flux reprogramming features both shared across all accessory proteins and specific for each accessory protein. Notably, a downregulated amino acid metabolism was observed in ORF9b, ORF9c and ORF10, while an upregulated lipid metabolism was distinctly induced by ORF3a. These findings reveal metabolic dependencies and vulnerabilities prompted by SARS-CoV-2 accessory proteins that may be exploited to identify new targets for intervention.
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COVID-19 , Mitocondrias , SARS-CoV-2 , Proteínas Virales , Humanos , Células A549 , COVID-19/metabolismo , COVID-19/virología , COVID-19/patología , Mitocondrias/metabolismo , Sistemas de Lectura Abierta , SARS-CoV-2/genética , Transcriptoma , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética , Proteínas Viroporinas/metabolismoRESUMEN
S-nitrosoglutathione reductase (GSNOR) is a denitrosylase enzyme that has been suggested to play a tumor suppressor role, although the mechanisms responsible are still largely unclear. In this study, we show that GSNOR deficiency in tumors is associated with poor prognostic histopathological features and poor survival in patients with colorectal cancer (CRC). GSNOR-low tumors were characterized by an immunosuppressive microenvironment with exclusion of cytotoxic CD8+ T cells. Notably, GSNOR-low tumors exhibited an immune evasive proteomic signature along with an altered energy metabolism characterized by impaired oxidative phosphorylation (OXPHOS) and energetic dependence on glycolytic activity. CRISPR-Cas9-mediated generation of GSNOR gene knockout (KO) CRC cells confirmed in vitro and in vivo that GSNOR-deficiency conferred higher tumorigenic and tumor-initiating capacities. Moreover, GSNOR-KO cells possessed enhanced immune evasive properties and resistance to immunotherapy, as revealed following xenografting them into humanized mouse models. Importantly, GSNOR-KO cells were characterized by a metabolic shift from OXPHOS to glycolysis to produce energy, as indicated by increased lactate secretion, higher sensitivity to 2-deoxyglucose (2DG), and a fragmented mitochondrial network. Real-time metabolic analysis revealed that GSNOR-KO cells operated close to their maximal glycolytic rate, as a compensation for lower OXPHOS levels, explaining their higher sensitivity to 2DG. Remarkably, this higher susceptibility to glycolysis inhibition with 2DG was validated in patient-derived xenografts and organoids from clinical GSNOR-low tumors. In conclusion, our data support the idea that metabolic reprogramming induced by GSNOR deficiency is an important mechanism for tumor progression and immune evasion in CRC and that the metabolic vulnerabilities associated with the deficiency of this denitrosylase can be exploited therapeutically. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Neoplasias , Oxidorreductasas , Ratones , Animales , Humanos , Linfocitos T CD8-positivos , Evasión Inmune , Proteómica , Microambiente TumoralRESUMEN
OBJECTIVE: We analyzed NAD+ metabolism in patients with rheumatoid arthritis (RA), its association with disease activity and clinical outcomes of RA, and the therapeutic potential of pharmacologic NAD+ boosting. METHODS: Our study included 253 participants. In the first cohort, comprising 153 RA patients and 56 healthy donors, we assessed NAD+ levels and NAD+ -related gene pathways. We analyzed 92 inflammatory molecules by proximity extension assay. In the second cohort, comprising 44 RA patients starting anti-tumor necrosis factor (anti-TNF) drugs, we evaluated changes in NAD+ levels and their association with clinical response after 3 months. Mechanistic studies were performed ex vivo on peripheral blood mononuclear cells (PBMCs) from patients with RA to test the beneficial effects of NAD+ boosters, such as nicotinamide and nicotinamide riboside. RESULTS: Reduced NAD+ levels were found in RA samples, in line with altered activity and expression of genes involved in NAD+ consumption (sirtuins, poly[ADP-ribose] polymerase, CD38), transport (connexin 43), and biosynthesis (NAMPT, NMNATs). Unsupervised clustering analysis identified a group of RA patients with the highest inflammatory profile, the lowest NAD+ levels, and the highest disease activity (as shown by the Disease Activity Score in 28 joints). NAD+ levels were modulated by anti-TNF therapy in parallel with the clinical response. In vitro studies using PBMCs from RA patients showed that nicotinamide riboside and nicotinamide increased NAD+ levels via NAMPT and NMNAT and reduced their prooxidative, proapoptotic, and proinflammatory status. CONCLUSION: RA patients display altered NAD+ metabolism, directly linked to their inflammatory and disease activity status, which was reverted by anti-TNF therapy. The preclinical beneficial effects of NAD+ boosters, as shown in leukocytes from RA patients, along with their proven clinical safety, might pave the way for the development of clinical trials using these compounds.
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Artritis Reumatoide , NAD , Humanos , NAD/metabolismo , Leucocitos Mononucleares/metabolismo , Inhibidores del Factor de Necrosis Tumoral , Niacinamida/uso terapéutico , Niacinamida/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismoRESUMEN
Dietary fats are important for human health, yet it is not fully understood how different fats affect various health problems. Although polyunsaturated fatty acids (PUFAs) are generally considered as highly oxidizable, those of the n-3 series can ameliorate the risk of many age-related disorders. Coenzyme Q (CoQ) is both an essential component of the mitochondrial electron transport chain and the only lipid-soluble antioxidant that animal cells can synthesize. Previous work has documented the protective antioxidant properties of CoQ against the autoxidation products of PUFAs. Here, we have explored in vitro and in vivo models to better understand the regulation of CoQ biosynthesis by dietary fats. In mouse liver, PUFAs increased CoQ content, and PUFAs of the n-3 series increased preferentially CoQ10. This response was recapitulated in hepatic cells cultured in the presence of lipid emulsions, where we additionally demonstrated a role for n-3 PUFAs as regulators of CoQ biosynthesis via the upregulation of several COQ proteins and farnesyl pyrophosphate levels. In both models, n-3 PUFAs altered the mitochondrial network without changing the overall mitochondrial mass. Furthermore, in cellular systems, n-3 PUFAs favored the synthesis of CoQ10 over CoQ9, thus altering the ratio between CoQ isoforms through a mechanism that involved downregulation of farnesyl diphosphate synthase activity. This effect was recapitulated by both siRNA silencing and by pharmacological inhibition of farnesyl diphosphate synthase with zoledronic acid. We highlight here the ability of n-3 PUFAs to regulate CoQ biosynthesis, CoQ content, and the ratio between its isoforms, which might be relevant to better understand the health benefits associated with this type of fat. Additionally, we identify for the first time zoledronic acid as a drug that inhibits CoQ biosynthesis, which must be also considered with respect to its biological effects on patients.
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Ácidos Grasos Omega-3 , Hígado/enzimología , Mitocondrias , Ubiquinona , Animales , Antioxidantes , Dieta , RatonesRESUMEN
Cellular senescence is a cell fate response characterized by a permanent cell cycle arrest driven primarily the by cell cycle inhibitor and tumor suppressor proteins p16Ink4a and p21Cip1/Waf1. In mice, the p21Cip1/Waf1 encoding locus, Cdkn1a, is known to generate two transcripts that produce identical proteins, but one of these transcript variants is poorly characterized. We show that the Cdkn1a transcript variant 2, but not the better-studied variant 1, is selectively elevated during natural aging across multiple mouse tissues. Importantly, mouse cells induced to senescence in culture by genotoxic stress (ionizing radiation or doxorubicin) upregulated both transcripts, but with different temporal dynamics: variant 1 responded nearly immediately to genotoxic stress, whereas variant 2 increased much more slowly as cells acquired senescent characteristics. Upon treating mice systemically with doxorubicin, which induces widespread cellular senescence in vivo, variant 2 increased to a larger extent than variant 1. Variant 2 levels were also more sensitive to the senolytic drug ABT-263 in naturally aged mice. Thus, variant 2 is a novel and more sensitive marker than variant 1 or total p21Cip1/Waf1 protein for assessing the senescent cell burden and clearance in mice.
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Envejecimiento/genética , Envejecimiento/patología , Senescencia Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Compuestos de Anilina/farmacología , Animales , Biomarcadores/metabolismo , Senescencia Celular/efectos de los fármacos , Ritmo Circadiano/efectos de los fármacos , Ritmo Circadiano/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Doxorrubicina/farmacología , Femenino , Masculino , Ratones Endogámicos C57BL , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estabilidad Proteica/efectos de los fármacos , Sulfonamidas/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genéticaRESUMEN
Coenzyme Q10 (CoQ10) is a mitochondrial electron carrier and a powerful lipophilic antioxidant located in membranes and plasma lipoproteins. CoQ10 is endogenously synthesized and obtained from the diet, which has raised interest in its therapeutic potential against pathologies related to mitochondrial dysfunction and enhanced oxidative stress. Novel formulations of solubilized CoQ10 and the stabilization of reduced CoQ10 (ubiquinol) have improved its bioavailability and efficacy. Synthetic analogues with increased solubility, such as idebenone, or accumulated selectively in mitochondria, such as MitoQ, have also demonstrated promising properties. CoQ10 has shown beneficial effects in autoimmune diseases. Leukocytes from antiphospholipid syndrome (APS) patients exhibit an oxidative perturbation closely related to the prothrombotic status. In vivo ubiquinol supplementation in APS modulated the overexpression of inflammatory and thrombotic risk-markers. Mitochondrial abnormalities also contribute to immune dysregulation and organ damage in systemic lupus erythematosus (SLE). Idebenone and MitoQ improved clinical and immunological features of lupus-like disease in mice. Clinical trials and experimental models have further demonstrated a therapeutic role for CoQ10 in Rheumatoid Arthritis, multiple sclerosis and type 1 diabetes. This review summarizes the effects of CoQ10 and its analogs in modulating processes involved in autoimmune disorders, highlighting the potential of these therapeutic approaches for patients with immune-mediated diseases.
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Coenzyme Q (CoQ, ubiquinone/ubiquinol) is a ubiquitous and unique molecule that drives electrons in mitochondrial respiratory chain and an obligatory step for multiple metabolic pathways in aerobic metabolism. Alteration of CoQ biosynthesis or its redox stage are causing mitochondrial dysfunctions as hallmark of heterogeneous disorders as mitochondrial/metabolic, cardiovascular, and age-associated diseases. Regulation of CoQ biosynthesis pathway is demonstrated to affect all steps of proteins production of this pathway, posttranslational modifications and protein-protein-lipid interactions inside mitochondria. There is a bi-directional relationship between CoQ and the epigenome in which not only the CoQ status determines the epigenetic regulation of many genes, but CoQ biosynthesis is also a target for epigenetic regulation, which adds another layer of complexity to the many pathways by which CoQ levels are regulated by environmental and developmental signals to fulfill its functions in eukaryotic aerobic metabolism.
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Eucariontes , Ubiquinona , Epigénesis Genética , Eucariontes/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Ubiquinona/metabolismoRESUMEN
Chronic nutrient excess leads to metabolic disorders and insulin resistance. Activation of stress-responsive pathways via Nrf2 activation contributes to energy metabolism regulation. Here, inducible activation of Nrf2 in mice and transgenesis of the Nrf2 target, NQO1, conferred protection from diet-induced metabolic defects through preservation of glucose homeostasis, insulin sensitivity, and lipid handling with improved physiological outcomes. NQO1-RNA interaction mediated the association with and inhibition of the translational machinery in skeletal muscle of NQO1 transgenic mice. NQO1-Tg mice on high-fat diet had lower adipose tissue macrophages and enhanced expression of lipogenic enzymes coincident with reduction in circulating and hepatic lipids. Metabolomics data revealed a systemic metabolic signature of improved glucose handling, cellular redox, and NAD+ metabolism while label-free quantitative mass spectrometry in skeletal muscle uncovered a distinct diet- and genotype-dependent acetylation pattern of SIRT3 targets across the core of intermediary metabolism. Thus, under nutritional excess, NQO1 transgenesis preserves healthful benefits.
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BACKGROUND: Radiographic axial spondyloarthritis (r-axSpA) is a chronic inflammatory form of arthritis in which tumor necrosis factor (TNF)-α, a potent inducer of inflammatory response and a key regulator of innate immunity and of Th1 immune responses, plays a central role. NETosis is a mechanism of innate immune defense that is involved in diverse rheumatology diseases. Nevertheless, spontaneous NETosis generation in r-axSpA, its association to disease pathogenesis, and the NETosis involvement on anti-TNF-α therapy's effects has never been explored. METHODS: Thirty r-axSpA patients and 32 healthy donors (HDs) were evaluated. Neutrophil extracellular trap (NET) formation, mediators of signal-transduction cascade required for NETosis induction and cell-free NETosis-derived products were quantified. An additional cohort of 15 r-axSpA patients treated with infliximab (IFX) for six months were further analyzed. In vitro studies were designed to assess the effects of IFX in NETosis generation and the inflammatory profile triggered. RESULTS: Compared to HDs, neutrophils from r-axSpA patients displayed augmented spontaneous NET formation, elevated expression of NET-associated signaling components, nuclear peptidylarginine deiminase 4 translocation and increased citrullinated histone H3. Furthermore, patients exhibited altered circulating levels of cell-free NETosis-derived products (DNA, nucleosomes and elastase). Additional studies revealed that cell-free NETosis-derived products could be suitable biomarkers for distinguish r-axSpA patients from HDs. Correlation studies showed association between cell-free NETosis-derived products and clinical inflammatory parameters. Besides, nucleosomes displayed potential as a biomarker for discriminate patients according to disease activity. IFX therapy promoted a reduction in both NETosis generation and disease activity in r-axSpA patients. Mechanistic in vitro studies further unveiled the relevance of IFX in reducing NET release and normalizing the augmented inflammatory activities promoted by NETs in mononuclear cells. CONCLUSIONS: This study reveals that NETosis is enhanced in r-axSpA patients and identifies the NETosis-derived products as potential disease activity biomarkers. In addition, the data suggests the potential role of NET generation analysis for assessment of therapeutic effectiveness in r-axSpA.
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Antiinflamatorios no Esteroideos/uso terapéutico , Trampas Extracelulares/fisiología , Infliximab/uso terapéutico , Espondiloartritis/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Biomarcadores , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , España , Espondiloartritis/etiologíaRESUMEN
Chronic kidney disease (CKD) is one of the fastest-growing causes of death and is predicted to become by 2040 the fifth global cause of death. CKD is characterized by increased oxidative stress and chronic inflammation. However, therapies to slow or prevent CKD progression remain an unmet need. Nrf2 (nuclear factor erythroid 2-related factor 2) is a transcription factor that plays a key role in protection against oxidative stress and regulation of the inflammatory response. Consequently, the use of compounds targeting Nrf2 has generated growing interest for nephrologists. Pre-clinical and clinical studies have demonstrated that Nrf2-inducing strategies prevent CKD progression and protect from acute kidney injury (AKI). In this article, we review current knowledge on the protective mechanisms mediated by Nrf2 against kidney injury, novel therapeutic strategies to induce Nrf2 activation, and the status of ongoing clinical trials targeting Nrf2 in renal diseases.
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Calorie restriction (CR) is one of the most robust means to improve health and survival in model organisms. CR imposes a metabolic program that leads to increased stress resistance and delayed onset of chronic diseases, including cancer. In rodents, CR induces the upregulation of two NADH-dehydrogenases, namely NAD(P)H:quinone oxidoreductase 1 (Nqo1) and cytochrome b5 reductase 3 (Cyb5r3), which provide electrons for energy metabolism. It has been proposed that this upregulation may be responsible for some of the beneficial effects of CR, and defects in their activity are linked to aging and several age-associated diseases. However, it is unclear whether changes in metabolic homeostasis solely through upregulation of these NADH-dehydrogenases have a positive impact on health and survival. We generated a mouse that overexpresses both metabolic enzymes leading to phenotypes that resemble aspects of CR including a modest increase in lifespan, greater physical performance, a decrease in chronic inflammation, and, importantly, protection against carcinogenesis, one of the main hallmarks of CR. Furthermore, these animals showed an enhancement of metabolic flexibility and a significant upregulation of the NAD+ /sirtuin pathway. The results highlight the importance of these NAD+ producers for the promotion of health and extended lifespan.
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Restricción Calórica , Citocromo-B(5) Reductasa/genética , Regulación Enzimológica de la Expresión Génica , NAD(P)H Deshidrogenasa (Quinona)/genética , Animales , Citocromo-B(5) Reductasa/metabolismo , Metabolismo Energético , Longevidad , Masculino , Ratones , Ratones Transgénicos , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , RatasRESUMEN
OBJECTIVE: Antiphospholipid syndrome (APS) leukocytes exhibit an oxidative perturbation, directly linked to alterations in mitochondrial dynamics and metabolism. This disturbance is related to the patients' prothrombotic status and can be prevented by in vitro treatment with coenzyme Q10. Our aim was to investigate short-term effects of in vivo ubiquinol (reduced coenzyme Q10 [Qred]) supplementation on markers related to inflammation and thrombosis in APS through a prospective, randomized, crossover, placebo-controlled trial. APPROACH AND RESULTS: Thirty-six patients with APS were randomized to receive Qred (200 mg/d) or placebo for 1 month. Thirty-three patients with APS completed the intervention, which increased plasma coenzyme Q10. Qred improved endothelial function and decreased monocyte expression of prothrombotic and proinflammatory mediators, inhibited phosphorylation of thrombosis-related protein kinases, and decreased peroxides and percentage of monocytes with depolarized mitochondria; mitochondrial size was increased, and mitochondrial biogenesis-related genes were upregulated. Qred ameliorated extruded neutrophil extracellular traps in neutrophils and downregulated peroxides, intracellular elastase, and myeloperoxidase. Nanostring microRNA profiling revealed 20 microRNAs reduced in APS monocytes, and 16 of them, with a preponderance of cardiovascular disease-related target mRNAs, were upregulated. Monocytes gene profiling showed differential expression of 29 atherosclerosis-related genes, 23 of them changed by Qred. Interaction networks of genes and microRNAs were identified. Correlation studies demonstrated co-ordinated effects of Qred on thrombosis and endothelial function-associated molecules. CONCLUSIONS: Our results highlight the potential of Qred to modulate the overexpression of inflammatory and thrombotic risk markers in APS. Because of the absence of clinically significant side effects and its potential therapeutic benefits, Qred might act as safe adjunct to standard therapies in APS. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02218476.
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Síndrome Antifosfolípido/tratamiento farmacológico , Síndrome Antifosfolípido/fisiopatología , Ubiquinona/análogos & derivados , Vitaminas/uso terapéutico , Estudios Cruzados , Endotelio Vascular/fisiología , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Inflamación/fisiopatología , Masculino , Persona de Mediana Edad , Mitocondrias/fisiología , Monocitos/patología , Oxidación-Reducción , Estudios Prospectivos , Ubiquinona/uso terapéuticoRESUMEN
Nuclear factor E2-related factor-2 (Nrf2) is a cap'n'collar/basic leucine zipper (b-ZIP) transcription factor which acts as sensor of oxidative and electrophilic stress. Low levels of Nrf2 predispose cells to chemical carcinogenesis but a dark side of Nrf2 function also exists because its unrestrained activation may allow the survival of potentially dangerous damaged cells. Since Nrf2 inhibition may be of therapeutic interest in cancer, and a decrease of Nrf2 activity may be related with degenerative changes associated with aging, it is important to investigate how the lack of Nrf2 function activates molecular mechanisms mediating cell death. Murine Embryonic Fibroblasts (MEFs) bearing a Nrf2 deletion (Nrf2KO) displayed diminished cellular growth rate and shortened lifespan compared with wild-type MEFs. Basal rates of DNA fragmentation and histone H2A.X phosphorylation were higher in Nrf2KO MEFs, although steady-state levels of reactive oxygen species were not significantly increased. Enhanced rates of apoptotic DNA fragmentation were confirmed in liver and lung tissues from Nrf2KO mice. Apoptosis in Nrf2KO MEFs was associated with a decrease of Bcl-2 but not Bax levels, and with the release of the mitochondrial pro-apoptotic factors cytochrome c and AIF. Procaspase-9 and Apaf-1 were also increased in Nrf2KO MEFs but caspase-3 was not activated. Inhibition of XIAP increased death in Nrf2KO but not in wild-type MEFs. Mitochondrial ultrastructure was also altered in Nrf2KO MEFs. Our results support that Nrf2 deletion produces mitochondrial dysfunction associated with mitochondrial permeabilization, increasing basal apoptosis through a caspase-independent and AIF-dependent pathway.
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Carcinogénesis/genética , Mitocondrias/genética , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo/genética , Especies Reactivas de Oxígeno/metabolismo , Animales , Apoptosis/genética , Carcinogénesis/patología , Caspasa 1/genética , Proliferación Celular/genética , Fibroblastos/metabolismo , Fibroblastos/patología , Histonas , Hígado/metabolismo , Hígado/patología , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones Noqueados , Mitocondrias/ultraestructura , Factor 2 Relacionado con NF-E2/metabolismo , Permeabilidad , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteína X Asociada a bcl-2/genéticaRESUMEN
Calorie restriction (CR) consistently extends longevity and delays age-related diseases across several animal models. We have previously shown that different dietary fat sources can modulate life span and mitochondrial ultrastructure, function and membrane fatty acid composition in mice maintained on a 40% CR. In particular, animals consuming lard as the main fat source (CR-Lard) lived longer than CR mice consuming diets with soybean oil (CR-Soy) or fish oil (CR-Fish) as the predominant lipid source. In the present work, a transcriptomic analysis in the liver and skeletal muscle was performed in order to elucidate possible mechanisms underlying the changes in energy metabolism and longevity induced by dietary fat in CR mice. After 8 months of CR, transcription downstream of several mediators of inflammation was inhibited in liver. In contrast, proinflammatory signaling was increased in the CR-Fish versus other CR groups. Dietary fish oil induced a gene expression pattern consistent with increased transcriptional regulation by several cytokines (TNF, GM-CSF, TGF-ß) and sex hormones when compared to the other CR groups. The CR-Fish also had lower expression of genes involved in fatty acid biosynthesis and increased expression of mitochondrial and peroxisomal fatty acid ß-oxidation genes than the other CR diet groups. Our data suggest that a diet high in n-3 PUFA, partially reverts CR-related changes in gene expression of key processes, such as inflammation and steroid hormone signaling, and this may mitigate life span extension with CR in mice consuming diets high in fish oil.
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Restricción Calórica , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos Omega-3/farmacología , Hígado/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Animales , Peso Corporal , Perfilación de la Expresión Génica , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Tamaño de los Órganos , Distribución AleatoriaRESUMEN
Cytochrome b5 reductases (CYB5R) are required for the elongation and desaturation of fatty acids, cholesterol synthesis and mono-oxygenation of cytochrome P450 enzymes, all of which are associated with protection against metabolic disorders. However, the physiological role of CYB5R in the context of metabolism, healthspan and aging remains ill-defined. We generated CYB5R-overexpressing flies (CYB5R-OE) and created a transgenic mouse line overexpressing CYB5R3 (CYB5R3-Tg) in the C57BL/6J background to investigate the function of this class of enzymes as regulators of metabolism and age-associated pathologies. Gender- and/or stage-specific induction of CYB5R, and pharmacological activation of CYB5R with tetrahydroindenoindole extended fly lifespan. Increased expression of CYB5R3 was associated with significant improvements in several metabolic parameters that resulted in modest lifespan extension in mice. Diethylnitrosamine-induced liver carcinogenesis was reduced in CYB5R3-Tg mice. Accumulation of high levels of long-chain polyunsaturated fatty acids, improvement in mitochondrial function, decrease in oxidative damage and inhibition of chronic pro-inflammatory pathways occurred in the transgenic animals. These results indicate that CYB5R represents a new target in the study of genes that regulate lipid metabolism and healthspan.
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The Membrane Theory of Aging proposes that lifespan is inversely related to the level of unsaturation in membrane phospholipids. Calorie restriction (CR) without malnutrition extends lifespan in many model organisms, which may be related to alterations in membrane phospholipids fatty acids. During the last few years our research focused on studying how altering the predominant fat source affects the outcome of CR in mice. We have established four dietary groups: one control group fed 95 % of a pre-determined ad libitum intake (in order to prevent obesity), and three CR groups fed 40 % less than ad libitum intake. Lipid source for the control and one of the CR groups was soybean oil (high in n-6 PUFA) whereas the two remaining CR groups were fed diets containing fish oil (high in n-3 PUFA), or lard (high in saturated and monounsaturated fatty acids). Dietary intervention periods ranged from 1 to 18 months. We performed a longitudinal lifespan study and a cross-sectional study set up to evaluate several mitochondrial parameters which included fatty acid composition, H(+) leak, activities of electron transport chain enzymes, ROS generation, lipid peroxidation, mitochondrial ultrastructure, and mitochondrial apoptotic signaling in liver and skeletal muscle. These approaches applied to different cohorts of mice have independently indicated that lard as a fat source often maximizes the effects of 40 % CR on mice. These effects could be due to significant increases of monounsaturated fatty acids levels, in accordance with the Membrane Theory of Aging.
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Envejecimiento/metabolismo , Restricción Calórica , Grasas de la Dieta/administración & dosificación , Mitocondrias Hepáticas/metabolismo , Mitocondrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Factores de Edad , Envejecimiento/patología , Apoptosis , Grasas de la Dieta/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Aceites de Pescado/administración & dosificación , Aceites de Pescado/metabolismo , Peroxidación de Lípido , Longevidad , Potencial de la Membrana Mitocondrial , Mitocondrias Hepáticas/ultraestructura , Mitocondrias Musculares/ultraestructura , Modelos Biológicos , Músculo Esquelético/ultraestructura , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Aceite de Soja/administración & dosificación , Aceite de Soja/metabolismo , Factores de TiempoRESUMEN
Imbalance between proliferation and cell death accounts for several age-linked diseases. Aging, calorie restriction (CR), and fat source are all factors that may influence apoptotic signaling in liver, an organ that plays a central metabolic role in the organism. Here, we have studied the combined effect of these factors on a number of apoptosis regulators and effectors. For this purpose, animals were fed diets containing different fat sources (lard, soybean oil, or fish oil) under CR for 6 or 18 months. An age-linked increase in the mitochondrial apoptotic pathway was detected with CR, including a decrease in Bcl-2/Bax ratio, an enhanced release of cytochrome c to the cytosol and higher caspase-9 activity. However, these changes were not fully transmitted to the effectors apoptosis-inducing factor and caspase-3. CR (which abated aging-related inflammatory responses) and dietary fat altered the activities of caspases-8, -9, and -3. Apoptotic index (DNA fragmentation) and mean nuclear area were increased in aged animals with the exception of calorie-restricted mice fed a lard-based fat source. These results suggest possible protective changes in hepatic homeostasis with aging in the calorie-restricted lard group.
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Envejecimiento/metabolismo , Apoptosis , Restricción Calórica , Grasas de la Dieta/metabolismo , Hígado/metabolismo , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Citocromos c/metabolismo , Citosol/efectos de los fármacos , Genes bcl-2/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteína X Asociada a bcl-2/metabolismoRESUMEN
OBJECTIVE: Statins may have beneficial vascular effects in systemic lupus erythematosus (SLE) beyond their cholesterol-lowering action, although the mechanisms involved are not completely understood. We investigated potential mechanisms involved in the efficacy of fluvastatin in preventing atherothrombosis in SLE. METHODS: Eighty-five patients with SLE and 62 healthy donors were included in the study. Selected patients (n=27) received 20â mg/day fluvastatin for 1â month. Blood samples were obtained before the start and at the end of treatment. Monocytes from five patients were treated in vitro with fluvastatin. RESULTS: Increased prothrombotic and inflammatory variables were found in patients with SLE. SLE monocytes displayed altered mitochondrial membrane potential and increased oxidative stress. Correlation and association analyses demonstrated a complex interplay among autoimmunity, oxidative stress, inflammation and increased risk of atherothrombosis in SLE. Fluvastatin treatment of patients for 1 month reduced the SLE Disease Activity Index and lipid levels, oxidative status and vascular inflammation. Array studies on monocytes demonstrated differential expression in 799 genes after fluvastatin treatment. Novel target genes and pathways modulated by fluvastatin were uncovered, including gene networks involved in cholesterol and lipid metabolism, inflammation, oxidative stress and mitochondrial activity. Electron microscopy analysis showed increased density volume of mitochondria in monocytes from fluvastatin-treated patients, who also displayed higher expression of genes involved in mitochondrial biogenesis. In vitro treatment of SLE monocytes confirmed the results obtained in the in vivo study. CONCLUSIONS: Our overall data suggest that fluvastatin improves the impairment of a redox-sensitive pathway involved in processes that collectively orchestrate the pathophysiology of atherothrombosis in SLE.
Asunto(s)
Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Adulto , Aterosclerosis/fisiopatología , Enfermedades Cardiovasculares/fisiopatología , Estudios de Casos y Controles , Células Cultivadas , Comorbilidad , Ácidos Grasos Monoinsaturados/farmacología , Ácidos Grasos Monoinsaturados/uso terapéutico , Femenino , Fluvastatina , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Técnicas In Vitro , Indoles/farmacología , Indoles/uso terapéutico , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Resultado del TratamientoRESUMEN
Neuropathological symptoms of Alzheimer's disease appear in advances stages, once neuronal damage arises. Nevertheless, recent studies demonstrate that in early asymptomatic stages, ß-amyloid peptide damages the cerebral microvasculature through mechanisms that involve an increase in reactive oxygen species and calcium, which induces necrosis and apoptosis of endothelial cells, leading to cerebrovascular dysfunction. The goal of our work is to study the potential preventive effect of the lipophilic antioxidant coenzyme Q (CoQ) against ß-amyloid-induced damage on human endothelial cells. We analyzed the protective effect of CoQ against Aß-induced injury in human umbilical vein endothelial cells (HUVECs) using fluorescence and confocal microscopy, biochemical techniques and RMN-based metabolomics. Our results show that CoQ pretreatment of HUVECs delayed Aß incorporation into the plasma membrane and mitochondria. Moreover, CoQ reduced the influx of extracellular Ca(2+), and Ca(2+) release from mitochondria due to opening the mitochondrial transition pore after ß-amyloid administration, in addition to decreasing O2(.-) and H2O2 levels. Pretreatment with CoQ also prevented ß-amyloid-induced HUVECs necrosis and apoptosis, restored their ability to proliferate, migrate and form tube-like structures in vitro, which is mirrored by a restoration of the cell metabolic profile to control levels. CoQ protected endothelial cells from Aß-induced injury at physiological concentrations in human plasma after oral CoQ supplementation and thus could be a promising molecule to protect endothelial cells against amyloid angiopathy.
Asunto(s)
Péptidos beta-Amiloides/metabolismo , Endotelio Vascular/efectos de los fármacos , Estrés Oxidativo , Ubiquinona/análogos & derivados , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ubiquinona/farmacologíaRESUMEN
The exact mechanisms underlying the role of oxidative stress in the pathogenesis and the prothrombotic or proinflammatory status of antiphospholipid syndrome (APS) remain unknown. Here, we investigate the role of oxidative stress and mitochondrial dysfunction in the proatherothrombotic status of APS patients induced by IgG-antiphospholipid antibodies and the beneficial effects of supplementing cells with coenzyme Q(10) (CoQ(10)). A significant increase in relevant prothrombotic and inflammatory parameters in 43 APS patients was found compared with 38 healthy donors. Increased peroxide production, nuclear abundance of Nrf2, antioxidant enzymatic activity, decreased intracellular glutathione, and altered mitochondrial membrane potential were found in monocytes and neutrophils from APS patients. Accelerated atherosclerosis in APS patients was found associated with their inflammatory or oxidative status. CoQ(10) preincubation of healthy monocytes before IgG-antiphospholipid antibody treatment decreased oxidative stress, the percentage of cells with altered mitochondrial membrane potential, and the induced expression of tissue factor, VEGF, and Flt1. In addition, CoQ(10) significantly improved the ultrastructural preservation of mitochondria and prevented IgG-APS-induced fission mediated by Drp-1 and Fis-1 proteins. In conclusion, the oxidative perturbation in APS patient leukocytes, which is directly related to an inflammatory and pro-atherothrombotic status, relies on alterations in mitochondrial dynamics and metabolism that may be prevented, reverted, or both by treatment with CoQ(10).