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1.
Tumour Biol ; 42(10): 1010428320965284, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028168

RESUMO

Glucose, as the main consuming nutrient of the body, faces different destinies in cancer cells. Glycolysis, oxidative phosphorylation, and pentose phosphate pathways produce different glucose-derived metabolites and thus affect cells' bioenergetics differently. Tumor cells' dependency to aerobic glycolysis and other cancer-specific metabolism changes are known as the cancer hallmarks, distinct cancer cells from normal cells. Therefore, these tumor-specific characteristics receive the limelight as targets for cancer therapy. Glutamine, serine, and fatty acid oxidation together with 5-lipoxygenase are main pathways that have attracted lots of attention for cancer therapy. In this review, we not only discuss different tumor metabolism aspects but also discuss the metabolism roles in the promotion of cancer cells at different stages and their difference with normal cells. Besides, we dissect the inhibitors potential in blocking the main metabolic pathways to introduce the effective and non-effective inhibitors in the field.


Assuntos
Antineoplásicos/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Medicina de Precisão , Antineoplásicos/farmacologia , Ciclo do Ácido Cítrico/efeitos dos fármacos , Metabolismo Energético/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular/métodos , Neoplasias/etiologia , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Medicina de Precisão/métodos
2.
Niger J Clin Pract ; 23(9): 1194-1200, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32913156

RESUMO

Aim: This retrospective analysis aims to evaluate the correlation between blood glucose fluctuation (BGF) and heart rate variability (HRV) in patients with coronary heart disease (CHD) and type 2 diabetes mellitus (T2DM). Subjects and Methods: In total, 210 patients with CHD and T2DM from January 2014 to January 2019 admitted to Wenling Hospital of Traditional Chinese Medicine were enrolled in this study. Based on whether BGF existed, patients were allocated to BG control group and BG fluctuation group. The HRV parameters, frequency of adverse events, and Gensini score between groups were recorded and Pearson analysis was performed. Results: Results displayed that no significant differences in age, gender, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), alcohol consumption history, drinking history, or serum lipid were found between groups (P > 0.05 for all items). However, the BGF parameters were significantly higher while the HRV parameters were significantly lower in BG fluctuation group, compared with BG control group (P < 0.05 for all items). Pearson analysis showed that despite mean blood glucose (MBG) and mean amplitude of glycemic excursions (MAGE) both correlated with a standard deviation of NN intervals (SDNN) level, the correlation coefficient of MAGE-SDNN was much higher (-0.705 vs -0.185). Additionally, the frequencies of adverse events and Gensini scores were also significantly higher in the BG fluctuation group than the BG control group. Conclusions: It suggests that BGF strongly correlated with HRV in patients with CHD and T2DM. It also provides experimental instructions for clinical practice.


Assuntos
Glicemia/análise , Doença das Coronárias/complicações , Diabetes Mellitus Tipo 2/complicações , Glucose/metabolismo , Frequência Cardíaca/fisiologia , Adulto , Idoso , Índice de Massa Corporal , Doença das Coronárias/sangue , Doença das Coronárias/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Yonsei Med J ; 61(9): 780-788, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882762

RESUMO

PURPOSE: This research was designed to investigate how miR-542-5p regulates the progression of hyperglycemia and hyperlipoidemia. MATERIALS AND METHODS: An in vivo model with diabetic db/db mice and an in vitro model with forskolin/dexamethasone (FSK/DEX)-induced primary hepatocytes and HepG2 cells were employed in the study. Bioinformatics analysis was conducted to identify the expression of candidate miRNAs in the liver tissues of diabetic and control mice. H&E staining revealed liver morphology in diabetic and control mice. Pyruvate tolerance tests, insulin tolerance tests, and intraperitoneal glucose tolerance test were utilized to assess insulin resistance. ELISA was conducted to evaluate blood glucose and insulin levels. Red oil O staining showed lipid deposition in liver tissues. Luciferase reporter assay was used to depict binding between miR-542-5p and forkhead box O1 (FOXO1). RESULTS: MiR-542-5p expression was under-expressed in the livers of db/db mice. Further in vitro experiments revealed that FSK/DEX, which mimics the effects of glucagon and glucocorticoids, induced cellular glucose production in HepG2 cells and in primary hepatocytes cells. Notably, these changes were reversed by miR-542-5p. We found that transcription factor FOXO1 is a target of miR-542-5p. Further in vivo study indicated that miR-542-5p overexpression decreases FOXO1 expression, thereby reversing increases in blood glucose, blood lipids, and glucose-related enzymes in diabetic db/db mice. In contrast, anti-miR-542-5p exerted an adverse influence on blood glucose and blood lipid metabolism, and its stimulatory effects were significantly inhibited by sh-FOXO1 in normal control mice. CONCLUSION: Collectively, our results indicated that miR-542-5p inhibits hyperglycemia and hyperlipoidemia by targeting FOXO1.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Hiperglicemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , MicroRNAs/genética , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Teste de Tolerância a Glucose , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Hiperglicemia/metabolismo , Hiperlipidemias/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , MicroRNAs/metabolismo , MicroRNAs/farmacologia
4.
Nat Commun ; 11(1): 4791, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963229

RESUMO

The ability to absorb ingested nutrients is an essential function of all metazoans and utilizes a wide array of nutrient transporters found on the absorptive enterocytes of the small intestine. A unique population of patients has previously been identified with severe congenital malabsorptive diarrhea upon ingestion of any enteral nutrition. The intestines of these patients are macroscopically normal, but lack enteroendocrine cells (EECs), suggesting an essential role for this rare population of nutrient-sensing cells in regulating macronutrient absorption. Here, we use human and mouse models of EEC deficiency to identify an unappreciated role for the EEC hormone peptide YY in regulating ion-coupled absorption of glucose and dipeptides. We find that peptide YY is required in the small intestine to maintain normal electrophysiology in the presence of vasoactive intestinal polypeptide, a potent stimulator of ion secretion classically produced by enteric neurons. Administration of peptide YY to EEC-deficient mice restores normal electrophysiology, improves glucose and peptide absorption, diminishes diarrhea and rescues postnatal survival. These data suggest that peptide YY is a key regulator of macronutrient absorption in the small intestine and may be a viable therapeutic option to treat patients with electrolyte imbalance and nutrient malabsorption.


Assuntos
Células Enteroendócrinas/metabolismo , Absorção Intestinal/fisiologia , Transporte de Íons/fisiologia , Nutrientes/metabolismo , Animais , Enterócitos , Glucose/metabolismo , Células-Tronco Embrionárias Humanas , Humanos , Intestino Delgado , Intestinos , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo YY , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Peptídeo Intestinal Vasoativo/metabolismo , Trocador 3 de Sódio-Hidrogênio , Água/metabolismo
5.
Mol Genet Genomics ; 295(6): 1489-1500, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32948893

RESUMO

Glucose, fructose and mannose are the preferred carbon/energy sources for the yeast Saccharomyces cerevisiae. Absence of preferred energy sources activates glucose derepression, which is regulated by the kinase Snf1. Snf1 phosphorylates the transcriptional repressor Mig1, which results in its exit from the nucleus and subsequent derepression of genes. In contrast, Snf1 is inactive when preferred carbon sources are available, which leads to dephosphorylation of Mig1 and its translocation to the nucleus where Mig1 acts as a transcription repressor. Here we revisit the role of the three hexose kinases, Hxk1, Hxk2 and Glk1, in glucose de/repression. We demonstrate that all three sugar kinases initially affect Mig1 nuclear localization upon addition of glucose, fructose and mannose. This initial import of Mig1 into the nucleus was temporary; for continuous nucleocytoplasmic shuttling of Mig1, Hxk2 is required in the presence of glucose and mannose and in the presence of fructose Hxk2 or Hxk1 is required. Our data suggest that Mig1 import following exposure to preferred energy sources is controlled via two different pathways, where (1) the initial import is regulated by signals derived from metabolism and (2) continuous shuttling is regulated by the Hxk2 and Hxk1 proteins. Mig1 nucleocytoplasmic shuttling appears to be important for the maintenance of the repressed state in which Hxk1/2 seems to play an essential role.


Assuntos
Núcleo Celular/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Hexoquinase/metabolismo , Manose/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transporte Ativo do Núcleo Celular , Regulação Fúngica da Expressão Gênica , Hexoquinase/genética , Fosforilação , Transporte Proteico , Proteínas Repressoras/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética
6.
Nat Commun ; 11(1): 4718, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948777

RESUMO

Disturbances in glucose homeostasis and low-grade chronic inflammation culminate into metabolic syndrome that increase the risk for the development of type 2 diabetes mellitus (T2DM). The recently discovered group 2 innate lymphoid cells (ILC2s) are capable of secreting copious amounts of type 2 cytokines to modulate metabolic homeostasis in adipose tissue. In this study, we have established that expression of Death Receptor 3 (DR3), a member of the TNF superfamily, on visceral adipose tissue (VAT)-derived murine and peripheral blood human ILC2s is inducible by IL-33. We demonstrate that DR3 engages the canonical and/or non-canonical NF-κB pathways, and thus stimulates naïve and co-stimulates IL-33-activated ILC2s. Importantly, DR3 engagement on ILC2s significantly ameliorates glucose tolerance, protects against insulin-resistance onset and remarkably reverses already established insulin-resistance. Taken together, these results convey the potent role of DR3 as an ILC2 regulator and introduce DR3 agonistic treatment as a novel therapeutic avenue for treating T2DM.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Linfócitos/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/metabolismo , Adipócitos/metabolismo , Adolescente , Adulto , Idoso , Animais , Citocinas/metabolismo , Proteínas de Ligação a DNA/genética , Feminino , Glucose/metabolismo , Homeostase , Humanos , Imunidade Inata , Resistência à Insulina , Interleucina-33/metabolismo , Gordura Intra-Abdominal/metabolismo , Masculino , Síndrome Metabólica/complicações , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Membro 25 de Receptores de Fatores de Necrose Tumoral/uso terapêutico , Adulto Jovem
7.
Medicine (Baltimore) ; 99(34): e21821, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846824

RESUMO

BACKGROUND: Traditional Chinese medicine Tongxinluo (TXL) has been widely used to treat coronary artery disease in China, since it could reduce myocardial infarct size and ischemia/reperfusion injury in both non-diabetic and diabetic conditions. It has been shown that TXL could regulate peroxisome proliferator activated receptor-α (PPAR-α), a positive modulator of angiopoietin-like 4 (Angptl4), in diabetic rats. Endothelial junction substructure components, such as VE-cadherin, are involved in the protection of reperfusion injury. Thus, we hypothesized cell-intrinsic and endothelial-specific Angptl4 mediated the protection of TXL on endothelial barrier under high glucose condition against ischemia/reperfusion-injury via PPAR-α pathway. METHODS: Incubated with high glucose medium, the human cardiac microvascular endothelial cells (HCMECs) were then exposed to oxygen-glucose-serum deprivation (2 hours) and restoration (2 hours) stimulation, with or without TXL, insulin, or rhAngptl4 pretreatment. RESULTS: TXL, insulin, and rhAngptl4 had similar protective effects on the endothelial barrier. TXL treatment reversed the endothelial barrier breakdown in HCMECs significantly as identified by decreasing endothelial permeability, upregulating the expression of JAM-A, VE-cadherin, and integrin-α5 and increasing the membrane location of VE-cadherin and integrin-α5, and these effects of TXL were as effective as insulin and rhAngptl4. However, Angptl4 knock-down with small interfering RNA (siRNA) interference and PPAR-α inhibitor MK886 partially abrogated these beneficial effects of TXL. Western blotting also revealed that similar with insulin, TXL upregulated the expression of Angptl4 in HCMECs, which could be inhibited by Angptl4 siRNA or MK886 exposure. TXL treatment increased PPAR-α activity, which could be diminished by MK886 but not by Angptl4 siRNA. CONCLUSION: These data suggest cell-intrinsic and endothelial-specific Angptl4 mediates the protection of TXL against endothelial barrier breakdown during oxygen-glucose-serum deprivation and restoration under high glucose condition partly via the PPAR-α/Angptl4 pathway.


Assuntos
Proteína 4 Semelhante a Angiopoietina/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Endotélio/efeitos dos fármacos , Endotélio/fisiopatologia , PPAR alfa/metabolismo , Proteína 4 Semelhante a Angiopoietina/genética , Proteína 4 Semelhante a Angiopoietina/farmacologia , Caderinas/metabolismo , Permeabilidade Capilar , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Vasos Coronários/citologia , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Glucose/farmacologia , Humanos , Indóis/farmacologia , Insulina/farmacologia , Integrina alfa5/metabolismo , Inibidores de Lipoxigenase/farmacologia , Microvasos/citologia , Oxigênio/metabolismo , Oxigênio/farmacologia , Receptores de Superfície Celular/metabolismo , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais
8.
Ecotoxicol Environ Saf ; 202: 110954, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800228

RESUMO

Current study aims to determine difference in metal accumulation pattern in muscle of Liza parsia (pelagic, omnivore), Amblypharyngodon mola (surface feeder, herbivore) and Mystus gulio (benthic, carnivore) depending on their niche and feeding habit and how it affects the endogenous antioxidants and glucose metabolism in fish muscle. Fishes were collected from Malancha, Diamond Harbour and Chandanpiri, West Bengal, India. Concentrations of lead, zinc, cadmium, chromium were measured in water, sediment and fish muscle. Metal pollution index (MPI) and bioconcentration factor (BCF) was calculated to evaluate the ability of fish to accumulate specific metals in muscle tissue from the aquatic environment. Metal concentrations were found significantly higher (P < 0.05) in water, sediment, fish muscles from Malancha than Chandanpiri and Diamond Harbour. L. parsia (MPI: 0.4-1.6) showed highest metal deposition in their muscle followed by A. mola (MPI: 0.37-1.38) and M. gulio (MPI: 0.2-1.2). Malondealdehyde, superoxide dismutase, catalase, glutathione S transferase, glutathione reductase and cortisol levels increased in case of L. parsia from Malancha and Chandanpiri. Succinate dehydrogenase, lactate dehydrogenase, Ca+2 ATPase and cytochrome C oxidase levels were significantly (P < 0.05) lower at Malancha and Chandanpiri than Diamond Harbour. Heat shock protein (HSP70) expression was significantly (P < 0.05) higher in all fish species at Malancha followed by Chandanpiri and Diamond Harbour. Glucose, glycogen, hexokinase, phosphofructokinase and glycogen phosphorylase levels varied between sites and selected fish species. Serum cortisol level was measured and found to be the highest in L. parsia from Malancha (2.94 ± 0.12 ng/ml) and the lowest in M. gulio from Diamond Harbour (0.7 ± 0.05 ng/ml). The results indicate that metal toxicity alters antioxidant levels, oxidative status and energy production in fish in species specific manner. Our results also indicate that Mystus has the highest degree of adaptability in response to metal toxicity possibly due to its specific food habit and niche position. Therefore, it can be concluded that maintenance of oxidative and metabolic status to combat metal-induced oxidative load will be helpful for the fishes to acquire better resistance under such eco-physiological stress. Alteration of niche and interactive segregation in aquatic organism may be one of the key modulator of resistance against such stress.


Assuntos
Antioxidantes/metabolismo , Cyprinidae/metabolismo , Comportamento Alimentar/fisiologia , Glucose/metabolismo , Metais Pesados/toxicidade , Músculos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Cyprinidae/fisiologia , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Índia , Metais Pesados/metabolismo , Músculos/enzimologia , Músculos/metabolismo , Oxirredução , Especificidade da Espécie , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
9.
PLoS One ; 15(8): e0226235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797046

RESUMO

Plant-derived fuels and chemicals from renewable biomass have significant potential to replace reliance on petroleum and improve global carbon balance. However, plant biomass contains significant fractions of oligosaccharides that are not usable natively by many industrial microorganisms, including Escherichia coli, Saccharomyces cerevisiae, and Zymomonas mobilis. Even after chemical or enzymatic hydrolysis, some carbohydrate remains as non-metabolizable oligosaccharides (e.g., cellobiose or longer cellulose-derived oligomers), thus reducing the efficiency of conversion to useful products. To begin to address this problem for Z. mobilis, we engineered a strain (Z. mobilis GH3) that expresses a glycosyl hydrolase (GH) with ß-glucosidase activity from a related α-proteobacterial species, Caulobacter crescentus, and subjected it to an adaptation in cellobiose medium. Growth on cellobiose was achieved after a prolonged lag phase in cellobiose medium that induced changes in gene expression and cell composition, including increased expression and extracellular release of GH. These changes were reversible upon growth in glucose-containing medium, meaning they did not result from genetic mutation but could be retained upon transfer of cells to fresh cellobiose medium. After adaptation to cellobiose, our GH-expressing strain was able to convert about 50% of cellobiose to glucose within 24 h and use it for growth and ethanol production. Alternatively, pre-growth of Z. mobilis GH3 in sucrose medium enabled immediate growth on cellobiose. Proteomic analysis of cellobiose- and sucrose-adapted strains revealed upregulation of secretion-, transport-, and outer membrane-related proteins, which may aid release or surface display of GHs, entry of cellobiose into the periplasm, or both. Our two key findings are that Z. mobilis can be reprogrammed to grow on cellobiose as a sole carbon source and that this reprogramming is related to a natural response of Z. mobilis to sucrose that promotes sucrase production.


Assuntos
Celobiose/metabolismo , Zymomonas/crescimento & desenvolvimento , Zymomonas/metabolismo , Adaptação Fisiológica/fisiologia , Biomassa , Reprogramação Celular/genética , Reprogramação Celular/fisiologia , Celulose/metabolismo , Expressão Gênica/genética , Glucose/metabolismo , Hidrolases/metabolismo , Proteômica , Sacarase/metabolismo , Sacarose/metabolismo , Zymomonas/genética , beta-Glucosidase/metabolismo
10.
PLoS Genet ; 16(8): e1008982, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841230

RESUMO

High glucose diets are unhealthy, although the mechanisms by which elevated glucose is harmful to whole animal physiology are not well understood. In Caenorhabditis elegans, high glucose shortens lifespan, while chemically inflicted glucose restriction promotes longevity. We investigated the impact of glucose metabolism on aging quality (maintained locomotory capacity and median lifespan) and found that, in addition to shortening lifespan, excess glucose negatively impacts locomotory healthspan. Conversely, disrupting glucose utilization by knockdown of glycolysis-specific genes results in large mid-age physical improvements via a mechanism that requires the FOXO transcription factor DAF-16. Adult locomotory capacity is extended by glycolysis disruption, but maximum lifespan is not, indicating that limiting glycolysis can increase the proportion of life spent in mobility health. We also considered the largely ignored role of glucose biosynthesis (gluconeogenesis) in adult health. Directed perturbations of gluconeogenic genes that specify single direction enzymatic reactions for glucose synthesis decrease locomotory healthspan, suggesting that gluconeogenesis is needed for healthy aging. Consistent with this idea, overexpression of the central gluconeogenic gene pck-2 (encoding PEPCK) increases health measures via a mechanism that requires DAF-16 to promote pck-2 expression in specific intestinal cells. Dietary restriction also features DAF-16-dependent pck-2 expression in the intestine, and the healthspan benefits conferred by dietary restriction require pck-2. Together, our results describe a new paradigm in which nutritional signals engage gluconeogenesis to influence aging quality via DAF-16. These data underscore the idea that promotion of gluconeogenesis might be an unappreciated goal for healthy aging and could constitute a novel target for pharmacological interventions that counter high glucose consequences, including diabetes.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Fatores de Transcrição Forkhead/genética , Gluconeogênese/genética , Envelhecimento Saudável/genética , Animais , Restrição Calórica , Regulação da Expressão Gênica no Desenvolvimento/genética , Glucose/metabolismo , Humanos , Expectativa de Vida , Longevidade/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Transdução de Sinais/genética
11.
PLoS Genet ; 16(8): e1008996, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841242

RESUMO

The utilization of different carbon sources in filamentous fungi underlies a complex regulatory network governed by signaling events of different protein kinase pathways, including the high osmolarity glycerol (HOG) and protein kinase A (PKA) pathways. This work unraveled cross-talk events between these pathways in governing the utilization of preferred (glucose) and non-preferred (xylan, xylose) carbon sources in the reference fungus Aspergillus nidulans. An initial screening of a library of 103 non-essential protein kinase (NPK) deletion strains identified several mitogen-activated protein kinases (MAPKs) to be important for carbon catabolite repression (CCR). We selected the MAPKs Ste7, MpkB, and PbsA for further characterization and show that they are pivotal for HOG pathway activation, PKA activity, CCR via regulation of CreA cellular localization and protein accumulation, as well as for hydrolytic enzyme secretion. Protein-protein interaction studies show that Ste7, MpkB, and PbsA are part of the same protein complex that regulates CreA cellular localization in the presence of xylan and that this complex dissociates upon the addition of glucose, thus allowing CCR to proceed. Glycogen synthase kinase (GSK) A was also identified as part of this protein complex and shown to potentially phosphorylate two serine residues of the HOG MAPKK PbsA. This work shows that carbon source utilization is subject to cross-talk regulation by protein kinases of different signaling pathways. Furthermore, this study provides a model where the correct integration of PKA, HOG, and GSK signaling events are required for the utilization of different carbon sources.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/genética , Glucose/metabolismo , Quinases da Glicogênio Sintase/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Aspergillus nidulans/enzimologia , Repressão Catabólica/genética , Fungos/genética , Fungos/metabolismo , Glicerol/metabolismo , Concentração Osmolar , Fosforilação/genética , Mapas de Interação de Proteínas/genética , Proteínas Repressoras/genética , Xilose/metabolismo
12.
Nat Commun ; 11(1): 4292, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855421

RESUMO

Cost competitive conversion of biomass-derived sugars into biofuel will require high yields, high volumetric productivities and high titers. Suitable production parameters are hard to achieve in cell-based systems because of the need to maintain life processes. As a result, next-generation biofuel production in engineered microbes has yet to match the stringent cost targets set by petroleum fuels. Removing the constraints imposed by having to maintain cell viability might facilitate improved production metrics. Here, we report a cell-free system in a bioreactor with continuous product removal that produces isobutanol from glucose at a maximum productivity of 4 g L-1 h-1, a titer of 275 g L-1 and 95% yield over the course of nearly 5 days. These production metrics exceed even the highly developed ethanol fermentation process. Our results suggest that moving beyond cells has the potential to expand what is possible for bio-based chemical production.


Assuntos
Bioquímica/métodos , Butanóis/metabolismo , Enzimas/metabolismo , Acetolactato Sintase/química , Acetolactato Sintase/metabolismo , Trifosfato de Adenosina , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Bioquímica/instrumentação , Reatores Biológicos , Sistema Livre de Células , Evolução Molecular Direcionada , Enzimas/química , Enzimas/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Glucose/metabolismo , Temperatura , Termodinâmica
13.
PLoS Negl Trop Dis ; 14(8): e0008509, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32804927

RESUMO

Leishmania species are responsible for a broad spectrum of diseases, denominated Leishmaniasis, affecting over 12 million people worldwide. During the last decade, there have been impressive efforts for sequencing the genome of most of the pathogenic Leishmania spp. as well as hundreds of strains, but large-scale proteomics analyses did not follow these achievements and the Leishmania proteome remained mostly uncharacterized. Here, we report a comprehensive comparative study of the proteomes of strains representing L. braziliensis, L. panamensis and L. guyanensis species. Proteins extracted by SDS-mediated lysis were processed following the multi-enzyme digestion-filter aided sample preparation (FASP) procedure and analysed by high accuracy mass spectrometry. "Total Protein Approach" and "Proteomic Ruler" were applied for absolute quantification of proteins. Principal component analysis demonstrated very high reproducibility among biological replicates and a very clear differentiation of the three species. Our dataset comprises near 7000 proteins, representing the most complete Leishmania proteome yet known, and provides a comprehensive quantitative picture of the proteomes of the three species in terms of protein concentration and copy numbers. Analysis of the abundance of proteins from the major energy metabolic processes allow us to highlight remarkably differences among the species and suggest that these parasites depend on distinct energy substrates to obtain ATP. Whereas L. braziliensis relies the more on glycolysis, L. panamensis and L. guyanensis seem to depend mainly on mitochondrial respiration. These results were confirmed by biochemical assays showing opposite profiles for glucose uptake and O2 consumption in these species. In addition, we provide quantitative data about different membrane proteins, transporters, and lipids, all of which contribute for significant species-specific differences and provide rich substrate for explore new molecules for diagnosing purposes. Data are available via ProteomeXchange with identifier PXD017696.


Assuntos
Leishmania/metabolismo , Proteínas de Protozoários/metabolismo , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Leishmania/genética , Consumo de Oxigênio , Proteômica , Proteínas de Protozoários/genética , Especificidade da Espécie
14.
Nat Commun ; 11(1): 4107, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796836

RESUMO

Foamy macrophages, which have prominent lipid droplets (LDs), are found in a variety of disease states. Toll-like receptor agonists drive triacylglycerol (TG)-rich LD development in macrophages. Here we explore the basis and significance of this process. Our findings indicate that LD development is the result of metabolic commitment to TG synthesis on a background of decreased fatty acid oxidation. TG synthesis is essential for optimal inflammatory macrophage activation as its inhibition, which prevents LD development, has marked effects on the production of inflammatory mediators, including IL-1ß, IL-6 and PGE2, and on phagocytic capacity. The failure of inflammatory macrophages to make PGE2 when TG-synthesis is inhibited is critical for this phenotype, as addition of exogenous PGE2 is able to reverse the anti-inflammatory effects of TG synthesis inhibition. These findings place LDs in a position of central importance in inflammatory macrophage activation.


Assuntos
Inflamação/metabolismo , Lipidômica/métodos , Triglicerídeos/metabolismo , Animais , Células Cultivadas , Citometria de Fluxo , Glucose/metabolismo , Glicerol/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos/fisiologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia Eletrônica , Palmitatos/metabolismo , Análise de Sequência de RNA
15.
Nat Commun ; 11(1): 4154, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814778

RESUMO

The DNA damage response (DDR) coordinates DNA metabolism with nuclear and non-nuclear processes. The DDR kinase Rad53CHK1/CHK2 controls histone degradation to assist DNA repair. However, Rad53 deficiency causes histone-dependent growth defects in the absence of DNA damage, pointing out unknown physiological functions of the Rad53-histone axis. Here we show that histone dosage control by Rad53 ensures metabolic homeostasis. Under physiological conditions, Rad53 regulates histone levels through inhibitory phosphorylation of the transcription factor Spt21NPAT on Ser276. Rad53-Spt21 mutants display severe glucose dependence, caused by excess histones through two separable mechanisms: dampening of acetyl-coenzyme A-dependent carbon metabolism through histone hyper-acetylation, and Sirtuin-mediated silencing of starvation-induced subtelomeric domains. We further demonstrate that repression of subtelomere silencing by physiological Tel1ATM and Rpd3HDAC activities coveys tolerance to glucose restriction. Our findings identify DDR mutations, histone imbalances and aberrant subtelomeric chromatin as interconnected causes of glucose dependence, implying that DDR kinases coordinate metabolism and epigenetic changes.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Glucose/metabolismo , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ciclo Celular/genética , Quinase do Ponto de Checagem 2/genética , Dano ao DNA , Reparo do DNA , Inativação Gênica , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Serina/genética , Serina/metabolismo , Telômero/genética , Fatores de Transcrição/genética
16.
PLoS Biol ; 18(8): e3000757, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32833957

RESUMO

In eukaryotes, conserved mechanisms ensure that cell growth is coordinated with nutrient availability. Overactive growth during nutrient limitation ("nutrient-growth dysregulation") can lead to rapid cell death. Here, we demonstrate that cells can adapt to nutrient-growth dysregulation by evolving major metabolic defects. Specifically, when yeast lysine-auxotrophic mutant lys- encountered lysine limitation, an evolutionarily novel stress, cells suffered nutrient-growth dysregulation. A subpopulation repeatedly evolved to lose the ability to synthesize organosulfurs (lys-orgS-). Organosulfurs, mainly reduced glutathione (GSH) and GSH conjugates, were released by lys- cells during lysine limitation when growth was dysregulated, but not during glucose limitation when growth was regulated. Limiting organosulfurs conferred a frequency-dependent fitness advantage to lys-orgS- by eliciting a proper slow growth program, including autophagy. Thus, nutrient-growth dysregulation is associated with rapid organosulfur release, which enables the selection of organosulfur auxotrophy to better tune cell growth to the metabolic environment. We speculate that evolutionarily novel stresses can trigger atypical release of certain metabolites, setting the stage for the evolution of new ecological interactions.


Assuntos
Adaptação Fisiológica/genética , Lisina/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Nutrientes/farmacologia , Saccharomyces cerevisiae/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Evolução Biológica , Glucose/metabolismo , Glucose/farmacologia , Lisina/deficiência , Redes e Vias Metabólicas/genética , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Nutrientes/metabolismo , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Sirolimo/farmacologia , Estresse Fisiológico
17.
Nat Commun ; 11(1): 4319, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859923

RESUMO

Disrupted energy metabolism drives cell dysfunction and disease, but approaches to increase or preserve ATP are lacking. To generate a comprehensive metabolic map of genes and pathways that regulate cellular ATP-the ATPome-we conducted a genome-wide CRISPR interference/activation screen integrated with an ATP biosensor. We show that ATP level is modulated by distinct mechanisms that promote energy production or inhibit consumption. In our system HK2 is the greatest ATP consumer, indicating energy failure may not be a general deficiency in producing ATP, but rather failure to recoup the ATP cost of glycolysis and diversion of glucose metabolites to the pentose phosphate pathway. We identify systems-level reciprocal inhibition between the HIF1 pathway and mitochondria; glycolysis-promoting enzymes inhibit respiration even when there is no glycolytic ATP production, and vice versa. Consequently, suppressing alternative metabolism modes paradoxically increases energy levels under substrate restriction. This work reveals mechanisms of metabolic control, and identifies therapeutic targets to correct energy failure.


Assuntos
Trifosfato de Adenosina/metabolismo , Redes e Vias Metabólicas/genética , Redes e Vias Metabólicas/fisiologia , Trifosfato de Adenosina/genética , Sistemas CRISPR-Cas , Linhagem Celular , Metabolismo Energético , Feminino , Fibroblastos , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Glicólise/fisiologia , Hexoquinase/genética , Hexoquinase/metabolismo , Humanos , Células K562 , Metabolômica , Mitocôndrias/metabolismo , Via de Pentose Fosfato , Mutação Puntual
18.
Nat Commun ; 11(1): 4150, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811819

RESUMO

The systemic decline in autophagic activity with age impairs homeostasis in several tissues, leading to age-related diseases. A mechanistic understanding of adipocyte dysfunction with age could help to prevent age-related metabolic disorders, but the role of autophagy in aged adipocytes remains unclear. Here we show that, in contrast to other tissues, aged adipocytes upregulate autophagy due to a decline in the levels of Rubicon, a negative regulator of autophagy. Rubicon knockout in adipocytes causes fat atrophy and hepatic lipid accumulation due to reductions in the expression of adipogenic genes, which can be recovered by activation of PPARγ. SRC-1 and TIF2, coactivators of PPARγ, are degraded by autophagy in a manner that depends on their binding to GABARAP family proteins, and are significantly downregulated in Rubicon-ablated or aged adipocytes. Hence, we propose that age-dependent decline in adipose Rubicon exacerbates metabolic disorders by promoting excess autophagic degradation of SRC-1 and TIF2.


Assuntos
Adipócitos/metabolismo , Envelhecimento/fisiologia , Autofagia/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Doenças Metabólicas/metabolismo , Adipócitos/patologia , Adipogenia/genética , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Adiposidade/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Técnicas de Inativação de Genes , Glucose/genética , Glucose/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Metabolismo dos Lipídeos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , PPAR gama/metabolismo
19.
Nat Commun ; 11(1): 4055, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792504

RESUMO

Although metastasis is the most common cause of cancer deaths, metastasis-intrinsic dependencies remain largely uncharacterized. We previously reported that metastatic pancreatic cancers were dependent on the glucose-metabolizing enzyme phosphogluconate dehydrogenase (PGD). Surprisingly, PGD catalysis was constitutively elevated without activating mutations, suggesting a non-genetic basis for enhanced activity. Here we report a metabolic adaptation that stably activates PGD to reprogram metastatic chromatin. High PGD catalysis prevents transcriptional up-regulation of thioredoxin-interacting protein (TXNIP), a gene that negatively regulates glucose import. This allows glucose consumption rates to rise in support of PGD, while simultaneously facilitating epigenetic reprogramming through a glucose-fueled histone hyperacetylation pathway. Restoring TXNIP normalizes glucose consumption, lowers PGD catalysis, reverses hyperacetylation, represses malignant transcripts, and impairs metastatic tumorigenesis. We propose that PGD-driven suppression of TXNIP allows pancreatic cancers to avidly consume glucose. This renders PGD constitutively activated and enables metaboloepigenetic selection of additional traits that increase fitness along glucose-replete metastatic routes.


Assuntos
Cromatina/metabolismo , Glucose/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Animais , Transporte Biológico/genética , Transporte Biológico/fisiologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Reprogramação Celular/genética , Reprogramação Celular/fisiologia , Imunoprecipitação da Cromatina , Epigênese Genética/genética , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/genética , Fosfogluconato Desidrogenase/genética , Fosfogluconato Desidrogenase/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
20.
Ecotoxicol Environ Saf ; 205: 111089, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810645

RESUMO

Early molecular events after the exposure of heavy metals, such as aberrant DNA methylation, suggest that DNA methylation was important in regulating physiological processes for animals and accordingly could be used as environmental biomarkers. In the present study, we found that copper (Cu) exposure increased lipid content and induced the DNA hypermethylation at the whole genome level. Especially, Cu induced hypermethylation of glucose-regulated protein 78 (grp78) and peroxisome proliferator-activated receptor gamma coactivator-1α (pgc1α). CCAAT/enhancer binding protein α (C/EBPα) could bind to the methylated sequence of grp78, whereas C/EBPß could not bind to the methylated sequence of grp78. These synergistically influenced grp78 expression and increased lipogenesis. In contrast, DNA methylation of PGC1α blocked the specific protein 1 (SP1) binding and interfered mitochondrial function. Moreover, Cu increased reactive oxygen species (ROS) production, activated endoplasmic reticulum (ER) stress and damaged mitochondrial function, and accordingly increased lipid deposition. Notably, we found a new toxicological mechanism for Cu-induced lipid deposition at DNA methylation level. The measurement of DNA methylation facilitated the use of these epigenetic biomarkers for the evaluation of environmental risk.


Assuntos
Carpas/fisiologia , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carpas/metabolismo , Cobre/metabolismo , Estresse do Retículo Endoplasmático , Glucose/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Lipídeos , Metilação , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ativação Transcricional , Regulação para Cima
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