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1.
Ecotoxicol Environ Saf ; 226: 112803, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34571417

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme deficiency. Our previous study revealed the level of G6PD changed in wild type (WT) mice after benzene exposure. In this study, the pentose phosphate pathway (PPP) in regulation of benzene-induced hematotoxicity was investigated and other potential pathways were discovered in a G6PD deficiency mouse model. WT and G6PD mutation (G6PDmut) mice were exposed to benzene (diluted in corn oil) at doses of 0 and 160 mg/kg by subcutaneous injection for 5 days/week, 4 weeks. Peripheral blood samples and bone marrow cells (BMCs) were obtained and measured. The levels of nicotinamide adenine dinucleotide phosphate (NADPH),reduced glutathione (GSH) and malondialdehyde (MDA) were detected and comet assay was analyzed for DNA damage in BMCs. Finally, RNA sequencing (RNA-seq) of BMCs was performed. The results showed that white blood cells decreased significantly in G6PDmut mice compared with WT mice after benzene treatment. The ratio of hematopoietic stem/progenitor cells significantly decreased in G6PDmut mice exposed to benzene. The reduction of NADPH and GSH revealed the effect on PPP with G6PD deficiency, which then caused the increase of MDA and DNA damage. Finally, RNA-seq results suggested potential genes including SHROOM4, CAMK2B and REN1 played potential roles of G6PD deficiency on benzene-induced hematotoxicity. Renin-angiotensin system and cAMP signaling pathway were potentially involved in the process. Our study provides a better understanding for the effects of G6PD deficiency on benzene-induced hematotoxicity.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Animais , Benzeno/toxicidade , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa , Camundongos , Transdução de Sinais
2.
Molecules ; 26(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34443540

RESUMO

Helicobacter pylori (H. pylori) is a pathogen that can remain in the stomach of an infected person for their entire life. As a result, this leads to the development of severe gastric diseases such as gastric cancer. In addition, current therapies have several problems including antibiotics resistance. Therefore, new practical options to eliminate this bacterium, and its induced affections, are required to avoid morbidity and mortality worldwide. One strategy in the search for new drugs is to detect compounds that inhibit a limiting step in a central metabolic pathway of the pathogen of interest. In this work, we tested 55 compounds to gain insights into their possible use as new inhibitory drugs of H. pylori glucose-6-phosphate dehydrogenase (HpG6PD) activity. The compounds YGC-1; MGD-1, MGD-2; TDA-1; and JMM-3 with their respective scaffold 1,3-thiazolidine-2,4-dione; 1H-benzimidazole; 1,3-benzoxazole, morpholine, and biphenylcarbonitrile showed the best inhibitory activity (IC50 = 310, 465, 340, 204 and 304 µM, respectively). We then modeled the HpG6PD protein by homology modeling to conduct an in silico study of the chemical compounds and discovers its possible interactions with the HpG6PD enzyme. We found that compounds can be internalized at the NADP+ catalytic binding site. Hence, they probably exert a competitive inhibitory effect with NADP+ and a non-competitive or uncompetitive effect with G6P, that of the compounds binding far from the enzyme's active site. Based on these findings, the tested compounds inhibiting HpG6PD represent promising novel drug candidates against H. pylori.


Assuntos
Simulação por Computador , Inibidores Enzimáticos/farmacologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Helicobacter pylori/enzimologia , Vetores Genéticos/metabolismo , Glucosefosfato Desidrogenase/química , Glucosefosfato Desidrogenase/metabolismo , Helicobacter pylori/efeitos dos fármacos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas Recombinantes/isolamento & purificação , Homologia Estrutural de Proteína
3.
Cancer Sci ; 112(10): 4075-4086, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34310804

RESUMO

The regulatory relationship between silent information regulator 2 (SIRT2) and glucose 6-phosphate dehydrogenase (G6PD) in clear cell renal cell carcinoma (ccRCC) is still unclear. The present study aimed to explore the function of SIRT2 and its regulatory effect on G6PD in ccRCC. The Cancer Genome Atlas data mining of SIRT2 was first analyzed. Quantitative real-time PCR and western blot analyses were used to assess the mRNA and protein expression levels, respectively. Cell viability, colony formation, cell cycle, cell apoptosis, and TUNEL assays and EdU staining were used to investigate the roles of SIRT2 in ccRCC proliferation and apoptosis. The coimmunoprecipitation (Co-IP) assay was used to analyze the association between SIRT2 and G6PD in ccRCC cells. Quantitative Co-IP assay was used to detect the levels of G6PD ubiquitination and small ubiquitin-related modifier 1 (SUMO1). An in vivo experiment was also carried out to confirm in vitro findings. The results indicated that SIRT2 promoted ccRCC proliferation and inhibited apoptosis by regulating cell cycle and apoptosis related proteins. Silent information regulator 2 interacted with G6PD, facilitated its activity through deacetylation, and increased its stability by reducing its ubiquitination and enhancing its SUMO1 modification. Silent information regulator 2 also promoted ccRCC tumor development in vivo. Taken together, the present study indicated that SIRT2 promoted ccRCC progression by increasing G6PD activity and stability, and it could be a potential new diagnostic and therapeutic target for ccRCC.


Assuntos
Carcinoma de Células Renais/metabolismo , Cisteína Endopeptidases/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Neoplasias Renais/metabolismo , Sirtuína 2/fisiologia , Acetilação , Animais , Apoptose , Western Blotting , Carcinoma de Células Renais/patologia , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Sobrevivência Celular , Bases de Dados Genéticas , Progressão da Doença , Feminino , Humanos , Imunoprecipitação , Neoplasias Renais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Modificação Traducional de Proteínas , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco , Ubiquitinação
4.
Biochim Biophys Acta Mol Basis Dis ; 1867(10): 166185, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087423

RESUMO

Autism Spectrum Disorder (ASD) is a common group of neurodevelopmental disorders which causes significant alterations in social and communication skills along with repetitive behavior and limited interests. The physiological understanding of ASD is ambiguous. Several reports suggested that environmental, genetic and epigenetic changes, neuroinflammation, mitochondrial dysfunction and metabolic alterations orchestrate the pathological outcomes of ASD. A recent report from Saudi Arabia found a mutation in X-chromosomal housekeeping glucose 6-phosphate dehydrogenase (G6PD) gene in two male ASD patients. Although, the involvement of G6PD-deficiency in the pathogenesis of ASD is poorly understood. Several reports suggested that G6PD deficiency impedes cellular detoxification of reactive oxygen species (ROS), which may result in neuronal damage and neuroinflammation. A deficiency of G6PD in newborn children may play a fundamental role in the pathogenesis of ASD. In this review, we will discuss the implications of G6PD deficiency in pathogenesis, male biasness and theranostics in ASD patients.


Assuntos
Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/genética , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Animais , Transtorno do Espectro Autista/metabolismo , Glucose/genética , Glucose/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Humanos , Mutação/genética , Espécies Reativas de Oxigênio/metabolismo
5.
Microb Cell Fact ; 20(1): 105, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034730

RESUMO

BACKGROUND: Commercial xylose purification produces xylose mother liquor (XML) as a major byproduct, which has become an inexpensive and abundant carbon source. A portion of this XML has been used to produce low-value-added products such as caramel but the remainder often ends up as an organic pollutant. This has become an issue of industrial concern. In this study, a uracil-deficient Candida tropicalis strain was engineered to efficiently convert XML to the commercially useful product xylitol. RESULTS: The xylitol dehydrogenase gene was deleted to block the conversion of xylitol to xylulose. Then, an NADPH regeneration system was added through heterologous expression of the Yarrowia lipolytica genes encoding 6-phosphate-gluconic acid dehydrogenase and 6-phosphate-glucose dehydrogenase. After process optimization, the engineered strain, C. tropicalis XZX-B4ZG, produced 97.10 g L- 1 xylitol in 120 h from 300 g L- 1 XML in a 5-L fermenter. The xylitol production rate was 0.82 g L- 1 h- 1 and the conversion rate was 92.40 %. CONCLUSIONS: In conclusion, this study performed a combination of metabolic engineering and process optimizing in C. tropicalis to enhance xylitol production from XML. The use of C. tropicalis XZX-B4ZG, therefore, provided a convenient method to transform the industrial by-product XML into the useful material xylitol.


Assuntos
Candida tropicalis/genética , Candida tropicalis/metabolismo , D-Xilulose Redutase/genética , Engenharia Metabólica , Xilitol/biossíntese , Xilose/metabolismo , Candida tropicalis/enzimologia , D-Xilulose Redutase/metabolismo , Fermentação , Glucose 1-Desidrogenase , Glucosefosfato Desidrogenase/metabolismo , Microbiologia Industrial
6.
Blood Cells Mol Dis ; 89: 102572, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33957359

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked inherited enzymopathic disorder that may lead to transfusion-requiring acute hemolytic anemia (AHA) triggered by fava beans ingestion, infection or some drugs. The gene encoding for G6PD carries a large number of genetic variants that have varying pathogenicity. We reported on three G6PD variants in the Gaza Strip Palestinian population with differing clinical impacts and frequencies: G6PD Mediterraneanc.563T, African G6PD A-c.202A/c.376G, and G6PD Cairoc.404C. We also identified a novel G6PD missense (Ser179Asn) mutation c.536G > A "G6PD Gaza". In this work we explore the effect of these four genetic variants on the structural and substrate (NADP+ and G6P) binding characteristics of the G6PD enzyme using the Monte Carlo (MC) flexible docking and molecular dynamics (MD) simulation approaches. We report that G6PD A-c.202A/c.376G, G6PD Mediterraneanc.563T, G6PD Cairoc.404C and G6PD Gazac.536A mutations cause significant structural changes in G6PD enzyme to induce conformational instability leading to the loss of binding of one or both substrates and are causative of G6PD deficiency.


Assuntos
Glucose-6-Fosfato/metabolismo , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , NADP/metabolismo , Mutação Puntual , Glucosefosfato Desidrogenase/química , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Multimerização Proteica
7.
PLoS Med ; 18(4): e1003576, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33891581

RESUMO

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) activity is dependent upon G6PD genotype and age of the red blood cell (RBC) population, with younger RBCs having higher activity. Peripheral parasitemia with Plasmodium spp. induces hemolysis, replacing older RBCs with younger cells with higher G6PD activity. This study aimed to assess whether G6PD activity varies between individuals with and without malaria or a history of malaria. METHODS AND FINDINGS: Individuals living in the Chittagong Hill Tracts of Bangladesh were enrolled into 3 complementary studies: (i) a prospective, single-arm clinical efficacy trial of patients (n = 175) with uncomplicated malaria done between 2014 and 2015, (ii) a cross-sectional survey done between 2015 and 2016 (n = 999), and (iii) a matched case-control study of aparasitemic individuals with and without a history of malaria done in 2020 (n = 506). G6PD activity was compared between individuals with and without malaria diagnosed by microscopy, rapid diagnostic test (RDT), or polymerase chain reaction (PCR), and in aparasitemic participants with and without a history of malaria. In the cross-sectional survey and clinical trial, 15.5% (182/1,174) of participants had peripheral parasitemia detected by microscopy or RDT, 3.1% (36/1,174) were positive by PCR only, and 81.4% (956/1,174) were aparasitemic. Aparasitemic individuals had significantly lower G6PD activity (median 6.9 U/g Hb, IQR 5.2-8.6) than those with peripheral parasitemia detected by microscopy or RDT (7.9 U/g Hb, IQR 6.6-9.8, p < 0.001), but G6PD activity similar to those with parasitemia detected by PCR alone (submicroscopic parasitemia) (6.1 U/g Hb, IQR 4.8-8.6, p = 0.312). In total, 7.7% (14/182) of patients with malaria had G6PD activity < 70% compared to 25.0% (248/992) of participants with submicroscopic or no parasitemia (odds ratio [OR] 0.25, 95% CI 0.14-0.44, p < 0.001). In the case-control study, the median G6PD activity was 10.3 U/g Hb (IQR 8.8-12.2) in 253 patients with a history of malaria and 10.2 U/g Hb (IQR 8.7-11.8) in 253 individuals without a history of malaria (p = 0.323). The proportion of individuals with G6PD activity < 70% was 11.5% (29/253) in the cases and 15.4% (39/253) in the controls (OR 0.7, 95% CI 0.41-1.23, p = 0.192). Limitations of the study included the non-contemporaneous nature of the clinical trial and cross-sectional survey. CONCLUSIONS: Patients with acute malaria had significantly higher G6PD activity than individuals without malaria, and this could not be accounted for by a protective effect of G6PD deficiency. G6PD-deficient patients with malaria may have higher than expected G6PD enzyme activity and an attenuated risk of primaquine-induced hemolysis compared to the risk when not infected.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Glucosefosfato Desidrogenase/metabolismo , Malária/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bangladesh/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Estudos Transversais , Feminino , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Humanos , Lactente , Recém-Nascido , Malária/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/epidemiologia , Parasitemia/parasitologia , Adulto Jovem
8.
Oncogene ; 40(14): 2567-2580, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33686238

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) is the first and rate-limiting enzyme in pentose phosphate pathway (PPP), excessive activation of which has been considered to be involved in tumorigenesis. Here, we show that tyrosine kinase c-Src interacts with and phosphorylates G6PD at Tyr 112. This phosphorylation enhances catalytic activity of G6PD by dramatically decreasing its Km value and increasing its Kcat value for substrate glucose-6-phosphate. Activated G6PD therefore augments the PPP flux for NADPH and ribose-5-phosphate production which is required for detoxification of intracellular reactive oxygen species (ROS) and biosynthesis of cancer cells, and eventually contributes to tumorigenesis. Consistently, c-Src activation is closely correlated with tyrosine phosphorylation and activity of G6PD in clinical colorectal cancer samples. We thus uncover another aspect of c-Src in promoting cell proliferation and tumorigenesis, deepening our understanding of c-Src as a proto-oncogene.


Assuntos
Proteína Tirosina Quinase CSK/metabolismo , Neoplasias Colorretais/enzimologia , Glucosefosfato Desidrogenase/metabolismo , Animais , Carcinogênese , Processos de Crescimento Celular/fisiologia , Neoplasias Colorretais/patologia , Ativação Enzimática , Células HCT116 , Células HEK293 , Células HeLa , Xenoenxertos , Humanos , Lipídeos/biossíntese , Masculino , Camundongos , Camundongos Nus , NADP/metabolismo , Fosforilação
9.
Cell Death Dis ; 12(3): 277, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723244

RESUMO

Glioma stem cells (GSCs) contribute to therapy resistance and poor outcomes for glioma patients. A significant feature of GSCs is their ability to grow in an acidic microenvironment. However, the mechanism underlying the rewiring of their metabolism in low pH remains elusive. Here, using metabolomics and metabolic flux approaches, we cultured GSCs at pH 6.8 and pH 7.4 and found that cells cultured in low pH exhibited increased de novo purine nucleotide biosynthesis activity. The overexpression of glucose-6-phosphate dehydrogenase, encoded by G6PD or H6PD, supports the metabolic dependency of GSCs on nucleotides when cultured under acidic conditions, by enhancing the pentose phosphate pathway (PPP). The high level of reduced glutathione (GSH) under acidic conditions also causes demand for the PPP to provide NADPH. Taken together, upregulation of G6PD/H6PD in the PPP plays an important role in acidic-driven purine metabolic reprogramming and confers a predilection toward glioma progression. Our findings indicate that targeting G6PD/H6PD, which are closely related to glioma patient survival, may serve as a promising therapeutic target for improved glioblastoma therapeutics. An integrated metabolomics and metabolic flux analysis, as well as considering microenvironment and cancer stem cells, provide a precise insight into understanding cancer metabolic reprogramming.


Assuntos
Acidose/metabolismo , Neoplasias Encefálicas/metabolismo , Metabolismo Energético , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Purinas/metabolismo , Acidose/genética , Acidose/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Desidrogenases de Carboidrato/genética , Desidrogenases de Carboidrato/metabolismo , Linhagem Celular Tumoral , Glioma/genética , Glioma/patologia , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Metabolômica , Células-Tronco Neoplásicas/patologia , Microambiente Tumoral
10.
Biochem Biophys Res Commun ; 553: 85-91, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33765558

RESUMO

Glucose-6-phosphate dehydrogenase is the first enzyme in the pentose phosphate pathway. The reaction catalyzed by the enzyme is considered to be the main source of reducing power for nicotinamide adenine dinucleotide phosphate (NADPH) and is a precursor of 5-carbon sugar used by cells. To uncover the structural features of the enzyme, we determined the crystal structures of glucose-6-phosphate dehydrogenase from Kluyveromyces lactis (KlG6PD) in both the apo form and a binary complex with its substrate glucose-6-phosphate. KlG6PD contains a Rossman-like domain for cofactor NADPH binding; it also presents a typical antiparallel ß sheet at the C-terminal domain with relatively the same pattern as those of other homologous structures. Moreover, our structural and biochemical analyses revealed that Lys153 contributes significantly to substrate G6P recognition. This study may provide insights into the structural variation and catalytic features of the G6PD enzyme.


Assuntos
Glucosefosfato Desidrogenase/química , Glucosefosfato Desidrogenase/metabolismo , Kluyveromyces/enzimologia , Sequência de Aminoácidos , Apoenzimas/química , Apoenzimas/genética , Apoenzimas/metabolismo , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Glucosefosfato Desidrogenase/genética , Cinética , Modelos Moleculares , Mutagênese , Relação Estrutura-Atividade , Especificidade por Substrato
11.
Microb Cell Fact ; 20(1): 32, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531004

RESUMO

BACKGROUND: Natural glycolysis encounters the decarboxylation of glucose partial oxidation product pyruvate into acetyl-CoA, where one-third of the carbon is lost at CO2. We previously constructed a carbon saving pathway, EP-bifido pathway by combining Embden-Meyerhof-Parnas Pathway, Pentose Phosphate Pathway and "bifid shunt", to generate high yield acetyl-CoA from glucose. However, the carbon conversion rate and reducing power of this pathway was not optimal, the flux ratio of EMP pathway and pentose phosphate pathway (PPP) needs to be precisely and dynamically adjusted to improve the production of mevalonate (MVA). RESULT: Here, we finely tuned the glycolytic flux ratio in two ways. First, we enhanced PPP flux for NADPH supply by replacing the promoter of zwf on the genome with a set of different strength promoters. Compared with the previous EP-bifido strains, the zwf-modified strains showed obvious differences in NADPH, NADH, and ATP synthesis levels. Among them, strain BP10BF accumulated 11.2 g/L of MVA after 72 h of fermentation and the molar conversion rate from glucose reached 62.2%. Second, pfkA was finely down-regulated by the clustered regularly interspaced short palindromic repeats interference (CRISPRi) system. The MVA yield of the regulated strain BiB1F was 8.53 g/L, and the conversion rate from glucose reached 68.7%. CONCLUSION: This is the highest MVA conversion rate reported in shaken flask fermentation. The CRISPRi and promoter fine-tuning provided an effective strategy for metabolic flux redistribution in many metabolic pathways and promotes the chemicals production.


Assuntos
Sistemas CRISPR-Cas/genética , Escherichia coli/enzimologia , Glucosefosfato Desidrogenase/metabolismo , Glicólise , Ácido Mevalônico/metabolismo , Fosfofrutoquinases/metabolismo , Trifosfato de Adenosina/metabolismo , Isótopos de Carbono , Regulação para Baixo , Metabolismo Energético , Fermentação , Análise do Fluxo Metabólico , NADP/metabolismo , Via de Pentose Fosfato , Regiões Promotoras Genéticas/genética
12.
J Am Chem Soc ; 143(7): 2694-2698, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33560827

RESUMO

The activation barriers ΔG⧧ for kcat/Km for the reactions of whole substrates catalyzed by 6-phosphogluconate dehydrogenase, glucose 6-phosphate dehydrogenase, and glucose 6-phosphate isomerase are reduced by 11-13 kcal/mol by interactions between the protein and the substrate phosphodianion. Between 4 and 6 kcal/mol of this dianion binding energy is expressed at the transition state for phosphite dianion activation of the respective enzyme-catalyzed reactions of truncated substrates d-xylonate or d-xylose. These and earlier results from studies on ß-phosphoglucomutase, triosephosphate isomerase, and glycerol 3-phosphate dehydrogenase define a cluster of six enzymes that catalyze reactions in glycolysis or of glycolytic intermediates, and which utilize substrate dianion binding energy for enzyme activation. Dianion-driven conformational changes, which convert flexible open proteins to tight protein cages for the phosphorylated substrate, have been thoroughly documented for five of these six enzymes. The clustering of metabolic enzymes which couple phosphodianion-driven conformational changes to enzyme activation suggests that this catalytic motif has been widely propagated in the proteome.


Assuntos
Glucose-6-Fosfato Isomerase/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Fosfogluconato Desidrogenase/metabolismo , Biocatálise , Ativação Enzimática , Cinética , Fosfitos/química , Fosfitos/metabolismo , Especificidade por Substrato , Termodinâmica , Xilose/metabolismo
13.
Reprod Toxicol ; 101: 50-62, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33548410

RESUMO

Evidences have shown that alterations in testicular dehydrogenase and ionic-ATPase activities have important implications in spermatogenesis and sperm capacitation, a penultimate biochemical change required for fertilization. Previous studies have revealed that taurine and coenzyme-Q10 (COQ-10), which are synergistic testicle-active bioflavonoids, with proven gonadotropin-enhancing properties reduce testicular damage in rats. Hence, this study investigated the effects of taurine and COQ-10 or their combination alone, and in the preventive and reversal of chlorpromazine-induced inhibition of testicular dehydrogenase enzymes, electrogenic pumps, sperm capacitation and acrosomal-reaction in male Wister rats. In the drug-treatment alone or preventive-protocol, rats received oral treatment of saline (10 mL/kg), taurine (150 mg/kg/day), COQ-10 (10 mg/kg/day) or both alone repeatedly for 56 days, or in combination with chlorpromazine (30 mg/kg/p.o./day) from days 29-56. In the reversal-protocol, the animals received chlorpromazine for 56 days prior to saline, taurine, COQ-10 or the combination from days 29-56. Thereafter, spermatogenesis (sperm count, viability, motility and morphology), testicular dehydrogenase [3beta-hydroxysteroid dehydrogenase (3ß-HSD), 17beta-hydroxysteroid dehydrogenase (17ß-HSD), glucose-6-phosphate dehydrogenase (G6PDH), lactate dehydrogenase-X (LDH-X)], ATPase (Na+/K+, Ca2+, Mg2+, H+) activities, sperm capacitation and acrosomal reaction were evaluated. Taurine and COQ-10 or their combination increased spermatogenesis, testicular 3ß-HSD, 17ß-HSD, G6PDH and LDH-X enzymes of naïve and chlorpromazine-treated rats. Both taurine and COQ-10 increased Na+/K+, Ca2+, Mg2+ and H+-ATPase activities. Also, taurine and COQ-10 or their combination prevented and reversed chlorpromazine-induced inhibition of sperm capacitation and acrosomal-reaction. The study showed that taurine and COQ-10 prevent and reverse chlorpromazine-induced inhibition of spermatogenesis, epididymal sperm capacitation and acrosomal reaction in rats through increased testicular dehydrogenases and electrogenic pump activities.


Assuntos
Antipsicóticos/toxicidade , Clorpromazina/toxicidade , Coenzimas/uso terapêutico , Flavonoides/uso terapêutico , Substâncias Protetoras/uso terapêutico , Taurina/uso terapêutico , Testículo/efeitos dos fármacos , 17-Hidroxiesteroide Desidrogenases/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Coenzimas/farmacologia , Sinergismo Farmacológico , Flavonoides/farmacologia , Glucosefosfato Desidrogenase/metabolismo , Isoenzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Taurina/farmacologia , Testículo/metabolismo
14.
Microbiology (Reading) ; 167(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33555250

RESUMO

l-Arabinose, a major constituent pentose of plant cell-wall polysaccharides, has been suggested to be a less preferred carbon source for fungi but to be a potential signalling molecule that can cause distinct genome-wide transcriptional changes in fungal cells. Here, we explore the possibility that this unique pentose influences the morphological characteristics of the phytopathogenic fungus Bipolaris maydis strain HITO7711. When grown on plate media under different sugar conditions, the mycelial dry weight of cultures on l-arabinose was as low as that with no sugar, suggesting that l-arabinose does not substantially contribute to vegetative growth. However, the intensity of conidiation on l-arabinose was comparable to or even higher than that on d-glucose and on d-xylose, in contrast to the poor conidiation under the no-sugar condition. To explore the physiological basis of the passive growth and active conidiation on l-arabinose, we next investigated cellular responses of the fungus to these sugar conditions. Transcriptional analysis of genes related to carbohydrate metabolism showed that l-arabinose stimulates carbohydrate utilization through the hexose monophosphate shunt (HMP shunt), a catabolic pathway parallel to glycolysis and which participates in the generation of the reducing agent NADPH (the reduced form of nicotinamide adenine dinucleotide phosphate). Then, the HMP shunt was impaired by disrupting the related gene BmZwf1, which encodes glucose-6-phosphate dehydrogenase in this fungus. The resulting mutants on l-arabinose showed remarkably decreased conidiation, but a conversely increased mycelial dry weight compared with the wild-type. Our study demonstrates that l-arabinose acts to enhance resource allocation to asexual reproduction in B. maydis HITO7711 at the cost of vegetative growth, and suggests that this is mediated by the concomitant stimulation of the HMP shunt.


Assuntos
Arabinose/metabolismo , Bipolaris/crescimento & desenvolvimento , Bipolaris/metabolismo , Bipolaris/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos Tipo Acasalamento , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Mutação , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Reprodução Assexuada , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo
15.
Cell Prolif ; 54(4): e13015, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33630390

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is a common malignant tumour with high morbidity and mortality. Metabolic regulation by oncogenes is necessary for tumour growth. Testes-specific protease 50 (TSP50) has been found to promote cell proliferation in multiple tumour types. However, the mechanism that TSP50 promotes HCC progression are not known. METHODS: Hepatocyte proliferation was analysed by MTT and BrdU incorporation after TSP50 transfection. Furthermore, LC-MS/MS, co-immunoprecipitation and GST pull-down assays were performed to analyse protein(s) binding to TSP50. Moreover, the site-specific mutation of G6PD was used to reveal the key site critical for G6PD acetylation mediated by TSP50. Finally, the role of G6PD K171 acetylation regulated by TSP50 in cell proliferation and tumour formation was investigated. RESULTS: Our data suggest that the overexpression of TSP50 accelerates hepatocyte proliferation. In addition, G6PD is an important protein that binds to TSP50 in the cytoplasm. TSP50 activates G6PD activity by inhibiting the acetylation of G6PD at the K171 site. In addition, TSP50 promotes the binding of G6PD to SIRT2. Furthermore, the K171ac of G6PD regulated by TSP50 is required for TSP50-induced cell proliferation in vitro and tumour formation in vivo. Additionally, according to The Cancer Genome Atlas (TCGA) programme, TSP50 and G6PD are negatively correlated with the survival of HCC patients. CONCLUSIONS: Collectively, our findings demonstrate that TSP50-induced cell proliferation and tumour formation are mediated by G6PD K171 acetylation.


Assuntos
Carcinoma Hepatocelular/patologia , Glucosefosfato Desidrogenase/metabolismo , Neoplasias Hepáticas/patologia , Serina Endopeptidases/metabolismo , Acetilação , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Linhagem Celular , Proliferação de Células , Feminino , Glucosefosfato Desidrogenase/genética , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Camundongos , Camundongos Nus , Mutagênese Sítio-Dirigida , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/genética , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Free Radic Res ; 55(4): 364-374, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33401987

RESUMO

The COVID-19 pandemic has so far affected more than 45 million people and has caused over 1 million deaths worldwide. Infection with SARS-CoV-2, the pathogenic agent, which is associated with an imbalanced redox status, causes hyperinflammation and a cytokine storm, leading to cell death. Glucose-6-phosphate dehydrogenase (G6PD) deficient individuals may experience a hemolytic crisis after being exposed to oxidants or infection. Individuals with G6PD deficiency are more susceptible to coronavirus infection than individuals with normally functioning G6PD. An altered immune response to viral infections is found in individuals with G6PD deficiency. Evidence indicates that G6PD deficiency is a predisposing factor of COVID-19.


Assuntos
COVID-19 , Deficiência de Glucosefosfato Desidrogenase , SARS-CoV-2/fisiologia , Viroses , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/genética , COVID-19/metabolismo , Suscetibilidade a Doenças , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Homeostase/fisiologia , Humanos , Oxirredução , Pandemias , Viroses/epidemiologia , Viroses/genética , Viroses/metabolismo
17.
Free Radic Biol Med ; 164: 149-153, 2021 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-33418115

RESUMO

NAD(P)H donates electrons for reductive biosynthesis and antioxidant defense across all forms of life. Glucose-6-phosphate dehydrogenase (G6PD) is a critical enzyme to provide NADPH. G6PD deficiency is present in more than 400 million people worldwide. This enzymopathy provides protection against malaria but sensitizes cells to oxidative stressors. Oxidative stress has been involved in the pathogenesis of the diabetic complications and several studies have provided evidences of a link between G6PD deficiency and type 2 diabetes (T2D). We hypothesized that a moderate overexpression of G6PD (G6PD-Tg) could protect ß-cells from age-associated oxidative stress thus reducing the risk of developing T2D. Here we report, that G6PD-Tg mice show an improved glucose tolerance and insulin sensitivity when compared to old age-matched Wild Type (WT) ones. This is accompanied by a decrease in oxidative damage and stress markers in the pancreas of the old Tg animals (20-24month-old). Pancreatic ß-cells progress physiologically towards a state of reduced responsiveness to glucose. In pancreatic islets isolated from G6PD-Tg and WT animals at different ages, and using electrophysiological techniques, we demonstrate a wider range of response to glucose in the G6PD-Tg cells that may explain the improvements in glucose tolerance and insulin sensitivity. Together, our results show that overexpression of G6PD maintains pancreatic ß-cells from old mice in a "juvenile-like" state and points to the G6PD dependent generation of NADPH as an important factor to improve the natural history of diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Deficiência de Glucosefosfato Desidrogenase , Células Secretoras de Insulina , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/genética , Células Secretoras de Insulina/metabolismo , Camundongos , Estresse Oxidativo
18.
Am J Physiol Heart Circ Physiol ; 320(3): H999-H1016, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33416454

RESUMO

We aimed to determine 1) the mechanism(s) that enables glucose-6-phosphate dehydrogenase (G6PD) to regulate serum response factor (SRF)- and myocardin (MYOCD)-driven smooth muscle cell (SMC)-restricted gene expression, a process that aids in the differentiation of SMCs, and 2) whether G6PD-mediated metabolic reprogramming contributes to the pathogenesis of vascular diseases in metabolic syndrome (MetS). Inhibition of G6PD activity increased (>30%) expression of SMC-restricted genes and concurrently decreased (40%) the growth of human and rat SMCs ex vivo. Expression of SMC-restricted genes decreased (>100-fold) across successive passages in primary cultures of SMCs isolated from mouse aorta. G6PD inhibition increased Myh11 (47%) while decreasing (>50%) Sca-1, a stem cell marker, in cells passaged seven times. Similarly, CRISPR-Cas9-mediated expression of the loss-of-function Mediterranean variant of G6PD (S188F; G6PDS188F) in rats promoted transcription of SMC-restricted genes. G6PD knockdown or inhibition decreased (48.5%) histone deacetylase (HDAC) activity, enriched (by 3-fold) H3K27ac on the Myocd promoter, and increased Myocd and Myh11 expression. Interestingly, G6PD activity was significantly higher in aortas from JCR rats with MetS than control Sprague-Dawley (SD) rats. Treating JCR rats with epiandrosterone (30 mg/kg/day), a G6PD inhibitor, increased expression of SMC-restricted genes, suppressed Serpine1 and Epha4, and reduced blood pressure. Moreover, feeding SD control (littermates) and G6PDS188F rats a high-fat diet for 4 mo increased Serpine1 and Epha4 expression and mean arterial pressure in SD but not G6PDS188F rats. Our findings demonstrate that G6PD downregulates transcription of SMC-restricted genes through HDAC-dependent deacetylation and potentially augments the severity of vascular diseases associated with MetS.NEW & NOTEWORTHY This study gives detailed mechanistic insight about the regulation of smooth muscle cell (SMC) phenotype by metabolic reprogramming and glucose-6-phosphate dehydrogenase (G6PD) in diabetes and metabolic syndrome. We demonstrate that G6PD controls the chromatin modifications by regulating histone deacetylase (HDAC) activity, which deacetylates histone 3-lysine 9 and 27. Notably, inhibition of G6PD decreases HDAC activity and enriches H3K27ac on myocardin gene promoter to enhance the expression of SMC-restricted genes. Also, we demonstrate for the first time that G6PD inhibitor treatment accentuates metabolic and transcriptomic reprogramming to reduce neointimal formation in coronary artery and large artery elastance in metabolic syndrome rats.


Assuntos
Glucosefosfato Desidrogenase/metabolismo , Histonas/metabolismo , Síndrome Metabólica/enzimologia , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Processamento de Proteína Pós-Traducional , Acetilação , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Glucosefosfato Desidrogenase/genética , Hemodinâmica , Humanos , Masculino , Síndrome Metabólica/genética , Síndrome Metabólica/patologia , Síndrome Metabólica/fisiopatologia , Camundongos Transgênicos , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiopatologia , Mutação , Miócitos de Músculo Liso/patologia , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ratos Sprague-Dawley , Fator de Resposta Sérica/genética , Fator de Resposta Sérica/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Remodelação Vascular
19.
Mol Med ; 27(1): 9, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514309

RESUMO

BACKGROUND: Reprogrammed glucose metabolism of enhanced Warburg effect (or aerobic glycolysis) is considered as a hallmark of cancer. Long non-coding RNAs (lncRNAs) have been certified to play a crucial role in tumor progression. The current study aims to inquire into the potential regulatory mechanism of long intergenic non-protein coding RNA 242 (LINC00242) on aerobic glycolysis in gastric cancer. METHOD: LINC00242, miR-1-3p and G6PD expression levels in gastric cancer tissues and cells were determined by qRT-PCR. Cell apoptosis or viability were examined by Flow cytometry or MTT assay. Western blot was utilized to investigate G6PD protein expression levels. Immunohistochemical (IHC) and hematoxylin and eosin (H&E) staining were used for histopathological detection. The targeted relationship between LINC00242 or G6PD and miR-1-3p was verified by luciferase reporter gene assay. Nude mouse xenograft was utilized to detect tumor formation in vivo. RESULT: LINC00242 and G6PD was high-expressed in gastric cancer tissues and cells, and LINC00242 is positively correlated with G6PD. Silencing of LINC00242 or G6PD within gastric cancer cells prominently inhibited cell proliferation and aerobic glycolysis in vitro and relieved the tumorigenesis of gastric cancer in vivo. miR-1-3p was predicted to directly target both LINC00242 and G6PD. Overexpression of miR-1-3p suppressed gastric cancer cells proliferation and aerobic glycolysis. LINC00242 competitively combined miR-1-3p, therefore relieving miR-1-3p-mediated suppression on G6PD. CONCLUSION: LINC00242 plays a stimulative role in gastric cancer aerobic glycolysis via regulation of miR-1-3p/ G6PD axis, therefore affecting gastric cancer cell proliferation.


Assuntos
Glucosefosfato Desidrogenase/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Glucosefosfato Desidrogenase/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Estadiamento de Neoplasias , Transplante de Neoplasias , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Efeito Warburg em Oncologia
20.
Molecules ; 26(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445584

RESUMO

Glucose 6-phosphate dehydrogenase (G6PDH) fulfills an essential role in cell physiology by catalyzing the production of NADPH+ and of a precursor for the de novo synthesis of ribose 5-phosphate. In trypanosomatids, G6PDH is essential for in vitro proliferation, antioxidant defense and, thereby, drug resistance mechanisms. So far, 16α-brominated epiandrosterone represents the most potent hit targeting trypanosomal G6PDH. Here, we extended the investigations on this important drug target and its inhibition by using a small subset of androstane derivatives. In Trypanosoma cruzi, immunofluorescence revealed a cytoplasmic distribution of G6PDH and the absence of signal in major organelles. Cytochemical assays confirmed parasitic G6PDH as the molecular target of epiandrosterone. Structure-activity analysis for a set of new (dehydro)epiandrosterone derivatives revealed that bromination at position 16α of the cyclopentane moiety yielded more potent T. cruzi G6PDH inhibitors than the corresponding ß-substituted analogues. For the 16α brominated compounds, the inclusion of an acetoxy group at position 3 either proved detrimental or enhanced the activity of the epiandrosterone or the dehydroepiandrosterone derivatives, respectively. Most derivatives presented single digit µM EC50 against infective T. brucei and the killing mechanism involved an early thiol-redox unbalance. This data suggests that infective African trypanosomes lack efficient NADPH+-synthesizing pathways, beyond the Pentose Phosphate, to maintain thiol-redox homeostasis.


Assuntos
Glucosefosfato Desidrogenase/metabolismo , Estágios do Ciclo de Vida , Esteroides/farmacologia , Trypanosoma brucei brucei/enzimologia , Trypanosoma brucei brucei/crescimento & desenvolvimento , Androsterona/química , Androsterona/farmacologia , Sítios de Ligação , Citosol/enzimologia , Desidroepiandrosterona/química , Desidroepiandrosterona/farmacologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Glucosefosfato Desidrogenase/química , Humanos , Estágios do Ciclo de Vida/efeitos dos fármacos , Modelos Moleculares , Oxirredução , Reprodutibilidade dos Testes , Trypanosoma brucei brucei/efeitos dos fármacos
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