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1.
Microb Cell Fact ; 18(1): 163, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31581944

RESUMO

BACKGROUND: Sustainable production of microbial fatty acids derivatives has the potential to replace petroleum based equivalents in the chemical, cosmetic and pharmaceutical industry. Most fatty acid sources for production oleochemicals are currently plant derived. However, utilization of these crops are associated with land use change and food competition. Microbial oils could be an alternative source of fatty acids, which circumvents the issue with agricultural competition. RESULTS: In this study, we generated a chimeric microbial production system that features aspects of both prokaryotic and eukaryotic fatty acid biosynthetic pathways targeted towards the generation of long chain fatty acids. We redirected the type-II fatty acid biosynthetic pathway of Escherichia coli BL21 (DE3) strain by incorporating two homologues of the beta-ketoacyl-[acyl carrier protein] synthase I and II from the chloroplastic fatty acid biosynthetic pathway of Arabidopsis thaliana. The microbial clones harboring the heterologous pathway yielded 292 mg/g and 220 mg/g DCW for KAS I and KAS II harboring plasmids respectively. Surprisingly, beta-ketoacyl synthases KASI/II isolated from A. thaliana showed compatibility with the FAB pathway in E. coli. CONCLUSION: The efficiency of the heterologous plant enzymes supersedes the overexpression of the native enzyme in the E. coli production system, which leads to cell death in fabF overexpression and fabB deletion mutants. The utilization of our plasmid based system would allow generation of plant like fatty acids in E. coli and their subsequent chemical or enzymatic conversion to high end oleochemical products.


Assuntos
Arabidopsis/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ácido Graxo Sintases/metabolismo , Ácidos Graxos/biossíntese , Engenharia Metabólica , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/síntese química , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Arabidopsis/enzimologia , Proteínas de Arabidopsis/síntese química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Vias Biossintéticas , Escherichia coli/enzimologia , Proteínas de Escherichia coli/genética , Ácido Graxo Sintases/genética , Ácidos Graxos/química , Isoenzimas/síntese química , Isoenzimas/genética , Isoenzimas/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo
2.
Gene ; 715: 144005, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31376410

RESUMO

Members of the highly conserved pleiotropic CK1 family of serine/threonine-specific kinases are tightly regulated in the cell and play crucial regulatory roles in multiple cellular processes from protozoa to human. Since their dysregulation as well as mutations within their coding regions contribute to the development of various different pathologies, including cancer and neurodegenerative diseases, they have become interesting new drug targets within the last decade. However, to develop optimized CK1 isoform-specific therapeutics in personalized therapy concepts, a detailed knowledge of the regulation and functions of the different CK1 isoforms, their various splice variants and orthologs is mandatory. In this review we will focus on the stress-induced CK1 isoform delta (CK1δ), thereby addressing its regulation, physiological functions, the consequences of its deregulation for the development and progression of diseases, and its potential as therapeutic drug target.


Assuntos
Caseína Quinase Idelta/química , Caseína Quinase Idelta/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimologia , Transdução de Sinais , Animais , Caseína Quinase Idelta/antagonistas & inibidores , Caseína Quinase Idelta/genética , Sistemas de Liberação de Medicamentos/métodos , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Relação Estrutura-Atividade
3.
Gene ; 716: 144032, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31377316

RESUMO

Mitochondrial folate metabolism is central to the generation of nucleotides, fuelling methylation reactions, and redox homeostasis. Uniquely among the reactions of the mitochondrial folate pathway, the key step of the oxidation of 5,10-methylene-tetrahydrofolate (CH2-THF) can be catalysed by two isozymes, MTHFD2 and MTHFD2L. The MTHFD2 enzyme has recently received considerable attention as an oncogenic enzyme upregulated in several tumour types, which is additionally required by cancer cells in vitro and in vivo. However, much less is currently known about MTHFD2L and its expression in cancer. In this study, we examine and compare the expression and regulation of the two mitochondrial MTHFD isozymes in normal human and cancer cells. We found that normal and cancer cells express both enzymes, although MTHFD2 has a much higher baseline expression. Unlike MTHFD2, the MTHFD2L isozyme does not show an association with proliferation and growth factor stimulation. In addition, we did not find evidence of a compensatory increase of MTHFD2L following suppression of its isozyme. This study supports that MTHFD2L is unlikely to have an important function in increased proliferation or cancer. Furthermore, therapeutic strategies aiming to block the mitochondrial folate pathway in cancer should focus on MTHFD2, with MTHFD2L being unlikely to be involved in the development of chemoresistance to targeting of its mitochondrial isozyme.


Assuntos
Aminoidrolases/metabolismo , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Enzimas Multifuncionais/metabolismo , Neoplasias/enzimologia , Aminoidrolases/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Isoenzimas/genética , Isoenzimas/metabolismo , Células MCF-7 , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Enzimas Multifuncionais/genética , Neoplasias/genética , Regulação para Cima
4.
J Enzyme Inhib Med Chem ; 34(1): 1526-1533, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31431095

RESUMO

A library of 4-[(3-methyl-4-aryl-2,3-dihydro-1,3-thiazol-2-ylidene)amino]benzene-1-sulphonamides (EMAC8002a-m) was designed and synthesised to evaluate the effect of substituents in the positions 3 and 4 of the dihydrothiazole ring on the inhibitory potency and selectivity toward human carbonic anhydrase isoforms I, II, IX, and XII. Most of the new compounds preferentially inhibit the isoforms II and XII. Both electronic and steric features on the aryl substituent in the position 4 of the dihydrothiazole ring concur to determine the overall biological activity of these new derivatives.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
5.
Anal Bioanal Chem ; 411(16): 3561-3579, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31183523

RESUMO

As synthetic cannabinoids are extensively metabolized, there is an urgent need for data on which metabolites can be used for successful urine screening. This study examines the in vitro metabolism of EG-018 and its 5F-analogue EG-2201 by means of comparing three different in vitro models: pooled human liver microsomes, cytochrome P450 isoenzymes, and a fungal approach utilizing the filamentous fungus Cunninghamella elegans LENDNER, which is known for its ability to mimic human biotransformation of xenobiotics. In addition, this study includes the screening of two authentic urine samples from individuals with proven EG-018 consumption, for the evaluation of in vitro-in vivo extrapolations made in the study. Incubation with pooled human liver microsomes yielded 15 metabolites of EG-018 belonging to six different metabolite subgroups, and 21 metabolites of EG-2201 belonging to seven different metabolite subgroups, respectively. Incubation with cytochrome P450 isoenzymes incubation yielded a further three EG-018 and five EG-2201 metabolites. With reference to their summed metabolite peak abundancies, the isoenzymes CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 were shown to contribute most to the microsomal metabolism of EG-018 and EG-2201. CYP2B6 was shown to make the lowest contribution, by far. As the phase I metabolism of both synthetic cannabinoids was shown to be distributed over a substantial number of different cytochrome P450 isoenzymes, it was concluded that it is likely to not be significantly affected by co-consumption of other drugs. Although fungal incubation with Cunninghamella elegans yielded an additional three EG-018 and four EG-2201 metabolites not observed after microsomal incubation, metabolites generated by Cunninghamella elegans were in good correlation with those generated by microsomal incubations. The fungal model demonstrated its ability to be an independent in vitro model in synthetic cannabinoid metabolism research. The three tested in vitro models enable sufficient predictive in vitro-in vivo extrapolations, comparable to those obtained from hepatocyte incubation published in the literature. In addition, with regard to the screening of authentic urine samples and comparison with the literature, one monohydroxylated EG-018 metabolite and two monohydroxylated EG-2201 metabolites can be recommended as urinary targets, on the basis of the tested in vitro models. Graphical abstract.


Assuntos
Canabinoides/metabolismo , Cunninghamella/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Isoenzimas/metabolismo , Microssomos Hepáticos/metabolismo , Canabinoides/urina , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas em Tandem/métodos
6.
J Enzyme Inhib Med Chem ; 34(1): 1172-1177, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31218888

RESUMO

A series of novel 8-substituted-N-(4-sulfamoylphenyl)quinoline-2-carboxamides was synthesised by the reaction of 8-hydroxy-N-(4-sulfamoylphenyl) quinoline-2-carboxamide with alkyl and benzyl halides. The compounds were assayed for carbonic anhydrase (CA) inhibitory activity against four hCA isoforms, hCA I, hCA II, hCA IV, and hCA IX. Barring hCA IX, all the isoforms were inhibited from low to high nanomolar range. hCA I was inhibited in the range of 61.9-8126 nM, with compound 5h having an inhibition constant of KI = 61.9 nM. hCA II was inhibited in the range of 33.0-8759 nM, with compound 5h having an inhibition constant of 33.0 nM and compounds 5a and 5b having inhibition constants of 88.4 and 85.7 nM, respectively. hCA IV was inhibited in the range of 657.2-6757 nM. Hence, compound 5h, possessing low nanomolar hCA I and II inhibition, can be selected as a lead for the design of novel CA I and II inhibitors.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade
7.
Artigo em Inglês | MEDLINE | ID: mdl-31176866

RESUMO

Cysteine oxygenase (CDO) is a mononuclear nonhemoglobin enzyme that catalyzes the production of taurine through the cysteine (Cys) pathway and plays a key role in the biosynthesis of taurine in mammals. However, the function of CDOs in bony fish remains poorly understood. In this study, we cloned CDO genes (CaCDO1 and CaCDO2) from Carassius auratus. The cDNA sequences of both CaCDO1 and CaCDO2 encoded putative proteins with 201 amino acids, which included structural features typical of the CDO protein family. Multiple sequence alignment and phylogenetic analysis showed that CaCDO1 and CaCDO2 shared high sequence identities and similarities with C. carpio homologs. Quantitative real-time polymerase chain reaction (qRT-PCR) results revealed that CaCDO1 and CaCDO2 were both broadly expressed in all selected tissues and developmental stages in C. auratus but had differing mRNA levels. In addition, compared to those of the taurine-free group, the in vivo mRNA expression levels of both CaCDO1 and CaCDO2 significantly decreased with increasing dietary taurine levels from 1.0 to 9.0 g/kg. Furthermore, in vitro taurine treatments showed similar inhibitory effects on the expression of CaCDO1 and CaCDO2 in the intestines of C. auratus. Our results also showed that the mRNA expression of CaCDO2 in the intestines was higher than that of CaCDO1 in response to in vivo and in vitro taurine supplementation. Overall, these data may provide new insights into the regulation of fish CDO expression and provide valuable knowledge for improving dietary formulas in aquaculture.


Assuntos
Cisteína Dioxigenase/genética , Cisteína Dioxigenase/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Carpa Dourada/genética , Carpa Dourada/metabolismo , Taurina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Carpa Dourada/crescimento & desenvolvimento , Isoenzimas/genética , Isoenzimas/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Taurina/farmacologia , Distribuição Tecidual
8.
Expert Opin Ther Pat ; 29(7): 509-533, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31172829

RESUMO

INTRODUCTION: The physiologic importance of fast CO2/HCO3- interconversion in various tissues requires the presence of carbonic anhydrase (CA, EC 4.2.1.1). Fourteen CA isozymes are present in humans, all of them being used as biomarkers. AREAS COVERED: A great number of patents and articles were focused on the use of CA isozymes as biomarkers for various diseases and syndromes in the recent years, in an ascending trend over the last decade. The review highlights the most important studies related with each isozyme and covers the most recent patent literature. EXPERT OPINION: The CAs biomarker research area expanded significantly in recent years, shifting from the predominant use of CA IX and CA XII in cancer diagnostic, staging, and prognosis towards a wider use of CA isozymes as disease biomarkers. CA isozymes are currently used either alone, in tandem with other CA isozymes and/or in combination with other proteins for the detection, staging, and prognosis of a huge repertoire of human dysfunctions and diseases, ranging from mild transformation of the normal tissues to extreme shifts in tissue organization and function. The techniques used for their detection/quantitation and the state-of-the-art in each clinical application are presented through relevant clinical examples and corresponding statistical data.


Assuntos
Biomarcadores/metabolismo , Anidrases Carbônicas/metabolismo , Isoenzimas/metabolismo , Animais , Humanos , Estadiamento de Neoplasias , Neoplasias/enzimologia , Neoplasias/patologia , Patentes como Assunto , Prognóstico
9.
J Enzyme Inhib Med Chem ; 34(1): 1164-1171, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31219348

RESUMO

Chagas disease and leishmaniasis are neglected tropical disorders caused by the protozoans Trypanosoma cruzi and Leishmania spp. Carbonic anhydrases (CAs, EC 4.2.1.1) from these protozoans (α-TcCA and ß-LdcCA) have been validated as promising targets for chemotherapic interventions. Many anti-protozoan agents, such as nitroimidazoles, nifurtimox, and benznidazole possess a nitro aromatic group in their structure which is crucial for their activity. As a continuation of our previous work on N-nitrosulfonamides as anti-protozoan agents, we investigated benzenesulfonamides bearing a nitro aromatic moiety against TcCA and LdcCA, observing selective inhibitions over human off-target CAs. Selected derivatives were assessed in vitro in different developmental stages of T. cruzi and Leishmania spp. A lack of significant growth inhibition has been found, which has been connected to the low permeability of this class of derivatives through cell membranes. Further strategies necessarily need to be designed for targeting Chagas disease and leishmaniasis with nitro-containing CA inhibitors.


Assuntos
Antiprotozoários/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Leishmania donovani/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Antiprotozoários/síntese química , Antiprotozoários/química , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Leishmania donovani/enzimologia , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Trypanosoma cruzi/enzimologia
10.
Nat Commun ; 10(1): 2607, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197133

RESUMO

Inhibiting the RAS oncogenic protein has largely been through targeting the switch regions that interact with signalling effector proteins. Here, we report designed ankyrin repeat proteins (DARPins) macromolecules that specifically inhibit the KRAS isoform by binding to an allosteric site encompassing the region around KRAS-specific residue histidine 95 at the helix α3/loop 7/helix α4 interface. We show that these DARPins specifically inhibit KRAS/effector interactions and the dependent downstream signalling pathways in cancer cells. Binding by the DARPins at that region influences KRAS/effector interactions in different ways, including KRAS nucleotide exchange and inhibiting KRAS dimerization at the plasma membrane. These results highlight the importance of targeting the α3/loop 7/α4 interface, a previously untargeted site in RAS, for specifically inhibiting KRAS function.


Assuntos
Sítio Alostérico/efeitos dos fármacos , Antineoplásicos/farmacologia , Desenho de Drogas , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Repetição de Anquirina , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Histidina/metabolismo , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Neoplasias/genética , Neoplasias/patologia , Biblioteca de Peptídeos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Multimerização Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Cell Physiol Biochem ; 52(6): 1535-1552, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31135122

RESUMO

BACKGROUND/AIMS: Pyruvate kinase M2 (PKM2) is essential for aerobic glycolysis. Although high PKM2 expression is observed in various cancer tissues, its functional role in cancer metabolism is unclear. Here, we investigated the role of PKM2 in regulating autophagy and its associated pathways in prostate cancer cells. METHODS: Immunohistochemistry was performed to compare the expression level of PKM2 in prostate cancer patients and normal human, whereas expression of PKM2 in several cell lines was also examined by using western blot. PKM2 expression was silenced using various small interfering RNAs (siRNAs). Cell viability was examined using IncuCyte ZOOM™ live cell imaging system. Western blotting and immunofluorescence were performed to investigate the PKM2 knockdown on other cellular signaling molecules. Acridine orange and Monodansylcadaverine staining was performed to check effect of PKM2 knockdown on autophagy induction. High performance thin layer chromatography was carried out to quantify the level of different cellular metabolites (pyruvate and lactate). Colony formation assay was performed to determine the ability of a cells to form large colonies. RESULTS: PKM2 was highly expressed in prostate cancer patients as compared to normal human. PKM2 siRNA-transfected prostate cancer cells showed significantly reduced viability. Acridine orange, Monodansylcadaverine staining and western blotting analysis showed that PKM2 downregulation markedly increased autophagic cell death. Results of western blotting analysis showed that PKM2 knockdown affected protein kinase B/mechanistic target of rapamycin 1 pathway, which consequently downregulated the expression of glycolytic enzymes lactate dehydrogenase A and glucose transporter 1. Knockdown of PKM2 also reduced the colony formation ability of human prostate cancer cell DU145. CONCLUSION: To the best of our knowledge, this is the first study to show that PKM2 inhibition alters prostate cancer cell metabolism and induces autophagy, thus providing new perspectives for developing PKM2-targeting anticancer therapies for treating prostate cancer.


Assuntos
Autofagia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piruvato Quinase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Transportador de Glucose Tipo 1/metabolismo , Humanos , Isoenzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Neoplasias da Próstata/metabolismo , Piruvato Quinase/antagonistas & inibidores , Piruvato Quinase/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
12.
Toxicol Lett ; 312: 173-180, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31082524

RESUMO

Triflumuron (TFM) is a benzoylurea insecticide commonly used in Tunisian agriculture and around the world to control crop pests and flies as a promising alternative to conventional insecticides for its arthropod specificity and low toxicity. From the evidence available in animal models, it can be expected that the metabolism of TFM is catalyzed by cytochrome P450 (CYP) and esterases. However, no data are available on human metabolism of TFM with regards to phase I metabolism and CYP isoform specificity. Hence, this manuscript describes experimental investigations to underpin in vitro phase I TFM metabolism in human samples for the first time. TFM biotransformation by recombinant human CYPs was characterized, then human liver microsomes (HLM) and chemical specific inhibitors have been used to identify the relative contribution of CYPs and esterases. Our results showed that all CYP isoforms were able to metabolize TFM with different affinity and efficiency. The relative contribution based both on the kinetic parameters and the CYP hepatic content was 3A4 > >2C9 > 2C8 > 2A6 > 1A2 > 2B6 > 2D6 > 2C19 > 2C18 > 1A1 at low TFM concentration, whilst at high TFM concentration it was 1A2 > >2C9 = 3A4 = 2A6 > 2C19 > 2B6 = 2C8 > 2D6 > 1A1 > 2C18. Experiments with HLMs confirmed the involvement of the most relevant CYPs in the presence of specific chemical inhibitors with a catalytic efficiency (Cliapp) lower by an order of magnitude compared with recombinant enzymes. Esterases were also relevant to the overall TFM kinetics and metabolism, with catalytic efficiency higher than that of CYPs. It is foreseen that such isoform-specific information in humans will further support in silico models for the refinement of the human risk assessment of single pesticides or mixtures.


Assuntos
Benzamidas/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Inseticidas/metabolismo , Isoenzimas/metabolismo , Microssomos Hepáticos/metabolismo , Humanos
13.
Yakugaku Zasshi ; 139(5): 837-844, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31061351

RESUMO

The hydrolysis activity and expression level of carboxylesterase (CES) in skin were compared with liver and intestine in the same individual of beagle dog and cynomolgus monkey, and their aging effects were studied. CES1 isozymes were mainly present in skin of both animals. The dermal hydrolysis activity was about 10 and 40% of hepatic activity in beagle dog and cynomolgus monkey, respectively. In beagle dog, the hydrolysis activity and the expression level of CES isozyme in liver and skin were nearly the same between 2- and 11-year-old individuals. On the other hand, the dermal hydrolase activity was lower in young individual than in old, in contrast to slight increase of hepatic and intestinal activity in old cynomolgus monkey. These differences by aging in cynomolgus monkey were related to the expression of CES1 proteins and their mRNA. Furthermore, mRNA level of human CES was investigated using total RNA of two individuals (63 and 85 years old). The two individuals showed approximately 2-fold higher expression of hCE2 than hCE1 in human skin.


Assuntos
Envelhecimento/metabolismo , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Intestinos/enzimologia , Fígado/enzimologia , Pele/enzimologia , Idoso de 80 Anos ou mais , Animais , Cães , Feminino , Expressão Gênica , Humanos , Hidrólise , Isoenzimas/genética , Isoenzimas/metabolismo , Macaca fascicularis , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Environ Monit Assess ; 191(6): 372, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101990

RESUMO

The expression levels of Esterase Isoenzyme and total soluble protein fractionation were studied in two coleopteran insects Blaps polycresta and Trachyderma hispida to evaluate the possible hazards from ceramic and plastic factories in the Khorshed Region, East of Alexandria, Egypt. Two insect collection sites were selected. The first site was the garden of the Faculty of Science, Moharram Bek, Alexandria University, which is considered a non-polluted site, and Khorshed district, considered as the polluted site. Percentages of heavy metals were estimated using SEM-X-ray microanalysis of soft tissues of both sexes of the two coleopteran insects. Esterase Isoenzymes were found to be overexpressed in B. Polycresta but not T. hispida. Female B. polycresta from the polluted site exhibited overexpression of the second and third loci. Furthermore, the females were found to be more affected than males, which only showed the overexpression of the second loci. T. hispida (females and males) collected from the reference site were found to have increased esterase activity compared with those sampled from the polluted site. The Snake-Skin™ Dialysis tubing technique, used for optimizing the protein extraction method, reflected the highest quantified proteins compared to other, traditional methods. SDS polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the whole-body protein reflected definite variations between T. hispida and B. polycresta in fraction number and activity at the two sites. Varied expression levels for metallothionein (MT) heavy metal resistance proteins for B. polycresta and T. hispida were also detected in the study. Based on these results, we suggest that biochemical biomarkers could infer environmental hazards, B. polycresta and T. hispida are successful biomarkers for heavy metal pollution.


Assuntos
Cerâmica , Besouros/efeitos dos fármacos , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Proteínas de Insetos/metabolismo , Isoenzimas/metabolismo , Animais , Biomarcadores/metabolismo , Besouros/genética , Besouros/metabolismo , Egito , Poluição Ambiental/efeitos adversos , Feminino , Expressão Gênica/efeitos dos fármacos , Indústrias , Proteínas de Insetos/genética , Isoenzimas/genética , Masculino , Metalotioneína/genética , Metalotioneína/metabolismo , Metais Pesados/análise , Metais Pesados/toxicidade , Fatores Sexuais , Especificidade da Espécie
15.
Food Chem ; 294: 231-237, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126458

RESUMO

A fully mechanized Arduino-controlled multi-pumping flow analysis system and procedure for the determination of ß-galactosidase activity are proposed. The applied bioanalytical method is based on the determination of p-nitrophenol formed in the course of enzyme-catalyzed hydrolysis of p-nitrophenyl-galactopyranosides. The photometric detection is performed using dedicated flow-through optoelectronic detector made of paired light emitting diodes. The developed bioanalytical system was applied for evaluation of optimal enzyme detection conditions (pH, temperature and reaction time), selection of appropriate substrate for the assays, comparison of enzymes of different origins (isoenzymes), detection of ß-galactosidase inhibitor and finally to the determination of enzyme activity in some dietary supplements dedicated for people suffering from lactose intolerance. Depending on measurements conditions the developed bioanalytical system allows determination of ß-galactosidase in the wide range of activity (up to 15 U/mL at detection limit ca 0.01 U/mL) with high sample flowthroughput (up to 30 detections per hour). Additionally, the potential utility of the developed analytical system for amyloglucosidase activity assays has been demonstrated.


Assuntos
Galactose/metabolismo , beta-Galactosidase/metabolismo , Biocatálise , Ensaios Enzimáticos , Galactose/química , Concentração de Íons de Hidrogênio , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Nitrofenóis/química , Temperatura Ambiente , beta-Galactosidase/antagonistas & inibidores
16.
Oxid Med Cell Longev ; 2019: 9192413, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049140

RESUMO

Oxidative stress induced by long-term glucocorticoid (GC) use weakens the repair capacity of bone tissue. Nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) oxidase (NOX) is a superoxide-generating enzyme that plays an important role in regulating bone metabolism. To clarify the role of nonphagocytic NOX isoforms in osteoblast reactive oxygen species (ROS) generation and apoptosis, dexamethasone was used to establish a high-dose GC environment in vitro. A dose-dependent increase in intracellular ROS generation was demonstrated, which was accompanied by increased osteoblastic MC3T3-E1 cell apoptosis. Addition of the ROS inhibitor NAC (N-acetyl-L-cysteine) or NOX inhibitor DPI (diphenyleneiodonium) reversed this effect, indicating that NOX-derived ROS can induce osteoblast apoptosis under high-dose dexamethasone stimulation. NOX1, NOX2, and NOX4 are NOX homologs recently identified in bone tissue. To clarify the NOX isoforms that play a role in osteoblast ROS generation, Nox1, Nox2, and Nox4 mRNA expression and NOX2 and NOX4 protein expression were analyzed. Nox1 and Nox4 mRNA expression was elevated in a dose-dependent manner after culture in 100 nM, 250 nM, 500 nM, or 1000 nM dexamethasone, and the increased expression of NOX1 mRNA was more significant compared with NOX4 mRNA. Small interfering RNAs (siRNAs) were used to confirm the role of NOX1 and NOX4 in ROS generation. To clarify the signaling pathway in ROS-induced osteoblast apoptosis, mitogen-activated protein kinase (MAPK) signaling molecules were analyzed. Phosphorylated ASK1 and p38 levels were significantly higher in the 1000 nM dexamethasone group, which NAC or DPI markedly attenuated. However, the total mRNA and protein levels of ASK1 and p38 between the dexamethasone group and control were not significantly different. This is related to ROS regulating the posttranslational modification of ASK1 and p38 in MC3T3-E1 cell apoptosis. Altogether, NOX1- and NOX4-derived ROS plays a pivotal role in high-dose dexamethasone-induced preosteoblast apoptosis by increasing phosphorylated ASK1 and p38 and may be an important mechanism in steroid-induced avascular necrosis of the femoral head (SANFH).


Assuntos
Apoptose/efeitos dos fármacos , Dexametasona/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteoblastos/enzimologia , Animais , Linhagem Celular , Dexametasona/efeitos adversos , Isoenzimas/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , Camundongos , NADP/metabolismo , Osteoblastos/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Int J Mol Sci ; 20(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035592

RESUMO

Tumor cells possess a high metabolic plasticity, which drives them to switch on the anaerobic glycolysis and lactate production when challenged by hypoxia. Among the enzymes mediating this plasticity through bidirectional conversion of pyruvate and lactate, the lactate dehydrogenase A (LDHA) and lactate dehydrogenase B (LDHB), are indicated. LDHA has a higher affinity for pyruvate, preferentially converting pyruvate to lactate, and NADH to NAD+ in anaerobic conditions, whereas LDHB possess a higher affinity for lactate, preferentially converting lactate to pyruvate, and NAD+ to NADH, when oxygen is abundant. Apart from the undisputed role of LDHA and LDHB in tumor cell metabolism and adaptation to unfavorable environmental or cellular conditions, these enzymes participate in the regulation of cell death. This review presents the latest progress made in this area on the roles of LDHA and LDHB in apoptosis and autophagy of tumor cells. Several examples of how LDHA and LDHB impact on these processes, as well as possible molecular mechanisms, will be discussed in this article. The information included in this review points to the legitimacy of modulating LDHA and/or LDHB to target tumor cells in the context of human and veterinary medicine.


Assuntos
Apoptose , Autofagia , L-Lactato Desidrogenase/metabolismo , Neoplasias/metabolismo , Animais , Linhagem Celular Tumoral , Metabolismo Energético , Humanos , Isoenzimas/metabolismo , Ácido Láctico/metabolismo
18.
J Agric Food Chem ; 67(31): 8431-8440, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067047

RESUMO

Glufosinate-resistant Lolium perenne L. spp. multiflorum biotypes from Oregon exhibited resistance levels up to 2.8-fold the field rate. One resistant biotype (MG) had an amino acid substitution in glutamine synthetase 2 (GS2), whereas the other (OR) exhibited the wild-type genotype. We hypothesized that the amino acid substitution in GS2 is involved in the resistance mechanism in MG and that non-target site resistance mechanisms are present in OR. OR metabolized glufosinate faster than the other two biotypes, with >75% of the herbicide metabolized in comparison to 50% in MG and the susceptible biotype. A mutation in GS2 co-segregating with resistance in MG did not reduce the enzyme activity, with results further supported by our enzyme homology models. This research supports the conclusion that a metabolism mechanism of glufosinate resistance is present in OR and that glufosinate resistance in MG is not due to an altered target site.


Assuntos
Aminobutiratos/metabolismo , Glutamato-Amônia Ligase/metabolismo , Resistência a Herbicidas , Herbicidas/metabolismo , Lolium/enzimologia , Proteínas de Plantas/metabolismo , Substituição de Aminoácidos , Aminobutiratos/farmacologia , Glutamato-Amônia Ligase/genética , Herbicidas/farmacologia , Isoenzimas/genética , Isoenzimas/metabolismo , Lolium/efeitos dos fármacos , Lolium/genética , Lolium/metabolismo , Mutação , Oregon , Proteínas de Plantas/genética
19.
Biol Pharm Bull ; 42(5): 850-855, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061331

RESUMO

Acyl-CoA synthetase long-chain family members (ACSLs) are a family of enzymes that convert long-chain free fatty acids into their acyl-CoAs. ACSL4 is an ACSL isozyme with a strong preference for arachidonic acid (AA) and has been hypothesized to modulate the metabolic fates of AA. There are two ACSL4 splice variants: ACSL4V1, which is the more abundant transcript, and ACSL4V2, which is believed to be restricted to the brain. In the present study, we expressed recombinant human ACSL4V1 and V2 in Spodoptera frugiperda 9 (Sf9) cells using the baculovirus expression system and then partially purified both variants by cobalt affinity column chromatography. We then established a novel ACSL assay system with LC-MS/MS, which is highly sensitive and applicable to various kinds of fatty acids, and used it to investigate the substrate specificity of recombinant human ACSL4V1 and V2. The results showed that both ACSL4 variants preferred various kinds of highly unsaturated fatty acids (HUFAs), including docosahexaenoic acid (DHA), adrenic acid (docosatetraenoic acid) and eicosapentaenoic acid (EPA), as well as AA as a substrate. Moreover, our kinetic studies revealed that the two variants had similar relative affinities for AA, EPA and DHA but different reaction rates for each HUFA. These results confirmed the importance of both of ACSL4 variants in the maintenance of membrane phospholipids bearing HUFAs. Structural analysis of these variants might reveal the molecular mechanism by which they maintain membrane phospholipids bearing HUFAs.


Assuntos
Coenzima A Ligases/metabolismo , Ácidos Graxos Insaturados/metabolismo , Animais , Baculoviridae/genética , Linhagem Celular , Cromatografia Líquida , Coenzima A Ligases/genética , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Spodoptera , Especificidade por Substrato , Espectrometria de Massas em Tandem
20.
Chem Biol Interact ; 307: 186-194, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31028727

RESUMO

The aldo-keto reductase (AKR) superfamily comprises NAD(P)H-dependent enzymes that catalyze the reduction of a variety of carbonyl compounds. AKRs are classified in families and subfamilies. Humans exhibit three members of the AKR1B subfamily: AKR1B1 (aldose reductase, participates in diabetes complications), AKR1B10 (overexpressed in several cancer types), and the recently described AKR1B15. AKR1B10 and AKR1B15 share 92% sequence identity, as well as the capability of being active towards retinaldehyde. However, AKR1B10 and AKR1B15 exhibit strong differences in substrate specificity and inhibitor selectivity. Remarkably, their substrate-binding sites are the most divergent parts between them. Out of 27 residue substitutions, six are changes to Phe residues in AKR1B15. To investigate the participation of these structural changes, especially the Phe substitutions, in the functional features of each enzyme, we prepared two AKR1B10 mutants. The AKR1B10 m mutant carries a segment of six AKR1B15 residues (299-304, including three Phe residues) in the respective AKR1B10 region. An additional substitution (Val48Phe) was incorporated in the second mutant, AKR1B10mF48. This resulted in structures with smaller and more hydrophobic binding pockets, more similar to that of AKR1B15. In general, the AKR1B10 mutants mirrored well the specific functional features of AKR1B15, i.e., the different preferences towards the retinaldehyde isomers, the much higher activity with steroids and ketones, and the unique behavior with inhibitors. It can be concluded that the Phe residues of loop C (299-304) contouring the substrate-binding site, in addition to Phe at position 48, strongly contribute to a narrower and more hydrophobic site in AKR1B15, which would account for its functional uniqueness. In addition, we have investigated the AKR1B10 and AKR1B15 activity toward steroids. While AKR1B10 only exhibits residual activity, AKR1B15 is an efficient 17-ketosteroid reductase. Finally, the functional role of AKR1B15 in steroid and retinaldehyde metabolism is discussed.


Assuntos
Aldo-Ceto Redutases/metabolismo , Engenharia de Proteínas , Retinoides/metabolismo , Esteroides/metabolismo , Aldo-Ceto Redutases/antagonistas & inibidores , Aldo-Ceto Redutases/genética , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Isomerismo , Cinética , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Retinaldeído/química , Retinaldeído/metabolismo , Retinoides/química , Alinhamento de Sequência , Esteroides/química , Especificidade por Substrato
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