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1.
Chem Pharm Bull (Tokyo) ; 67(6): 556-565, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31155561

RESUMO

Aldose reductase (AR) is associated with the onset of diabetic complications. Botryllazine A and its analogues were synthesized and evaluated for human AR inhibitory activity. Analogues possessing aromatic bicyclic systems at the C5 position of the central pyrazine ring exhibited superior AR inhibiting activity relative to the parent botryllazine A. In addition, the benzoyl groups at positions C2 and C3 of the pyrazine ring were dispensable for this improved inhibitory activity. Conversely, a benzoyl group-containing phenolic hydroxyl groups-at either position C2 or C3 of the pyrazine ring was essential for attainment of high inhibitory activity approaching that of sorbinil (a highly effective AR inhibitor).


Assuntos
Aldeído Redutase/metabolismo , Inibidores Enzimáticos/síntese química , Pirazinas/química , Aldeído Redutase/antagonistas & inibidores , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Humanos , Ligações de Hidrogênio , Concentração Inibidora 50 , Conformação Molecular , Simulação de Acoplamento Molecular , Pirazinas/síntese química , Pirazinas/metabolismo
2.
Nat Commun ; 10(1): 2698, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221959

RESUMO

The different stages of the metastatic cascade present distinct metabolic challenges to tumour cells and an altered tumour metabolism associated with successful metastatic colonisation provides a therapeutic vulnerability in disseminated disease. We identify the aldo-keto reductase AKR1B10 as a metastasis enhancer that has little impact on primary tumour growth or dissemination but promotes effective tumour growth in secondary sites and, in human disease, is associated with an increased risk of distant metastatic relapse. AKR1B10High tumour cells have reduced glycolytic capacity and dependency on glucose as fuel source but increased utilisation of fatty acid oxidation. Conversely, in both 3D tumour spheroid assays and in vivo metastasis assays, inhibition of fatty acid oxidation blocks AKR1B10High-enhanced metastatic colonisation with no impact on AKR1B10Low cells. Finally, mechanistic analysis supports a model in which AKR1B10 serves to limit the toxic side effects of oxidative stress thereby sustaining fatty acid oxidation in metabolically challenging metastatic environments.


Assuntos
Aldeído Redutase/metabolismo , Neoplasias da Mama/patologia , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia/patologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Ácidos Graxos/metabolismo , Feminino , Glicólise , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Recidiva Local de Neoplasia/metabolismo , Oxirredução , Estresse Oxidativo , Esferoides Celulares , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Microb Cell Fact ; 18(1): 83, 2019 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31103047

RESUMO

BACKGROUND: As renewable biomass, lignocellulose remains one of the major choices for most countries in tackling global energy shortage and environment pollution. Efficient utilization of xylose, an important monosaccharide in lignocellulose, is essential for the production of high-value compounds, such as ethanol, lipids, and isoprenoids. Protopanaxadiol (PPD), a kind of isoprenoids, has important medical values and great market potential. RESULTS: The engineered protopanaxadiol-producing Yarrowia lipolytica strain, which can use xylose as the sole carbon source, was constructed by introducing xylose reductase (XR) and xylitol dehydrogenase (XDH) from Scheffersomyces stipitis, overexpressing endogenous xylulose kinase (ylXKS) and heterologous PPD synthetic modules, and then 18.18 mg/L of PPD was obtained. Metabolic engineering strategies such as regulating cofactor balance, enhancing precursor flux, and improving xylose metabolism rate via XR (K270R/N272D) mutation, the overexpression of tHMG1/ERG9/ERG20 and transaldolase (TAL)/transketolase (TKL)/xylose transporter (TX), were implemented to enhance PPD production. The final Y14 strain exhibited the greatest PPD titer from xylose by fed-batch fermentation in a 5-L fermenter, reaching 300.63 mg/L [yield, 2.505 mg/g (sugar); productivity, 2.505 mg/L/h], which was significantly higher than the titer of glucose fermentation [titer, 167.17 mg/L; yield, 1.194 mg/g (sugar); productivity, 1.548 mg/L/h]. CONCLUSION: The results showed that xylose was more suitable for PPD synthesis than glucose due to the enhanced carbon flux towards acetyl-CoA, the precursor for PPD biosynthetic pathway. This is the first report to produce PPD in Y. lipolytica with xylose as the sole carbon source, which developed a promising strategy for the efficient production of high-value triterpenoid compounds.


Assuntos
Sapogeninas/metabolismo , Xilose/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Biomassa , Vias Biossintéticas , D-Xilulose Redutase/genética , D-Xilulose Redutase/metabolismo , Fermentação , Engenharia Metabólica/métodos , Redes e Vias Metabólicas , Organismos Geneticamente Modificados
4.
Int J Mol Sci ; 20(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959808

RESUMO

: Carnosic acid (CA) is a phytochemical found in some dietary herbs, such as Rosmarinus officinalis L., and possesses antioxidative and anti-microbial properties. We previously demonstrated that CA functions as an activator of nuclear factor, erythroid 2 (NF-E2)-related factor 2 (Nrf2), an oxidative stress-responsive transcription factor in human and rodent cells. CA enhances the expression of nerve growth factor (NGF) and antioxidant genes, such as HO-1 in an Nrf2-dependent manner in U373MG human astrocytoma cells. However, CA also induces NGF gene expression in an Nrf2-independent manner, since 50 µM of CA administration showed striking NGF gene induction compared with the classical Nrf2 inducer tert-butylhydroquinone (tBHQ) in U373MG cells. By comparative transcriptome analysis, we found that CA activates activating transcription factor 4 (ATF4) in addition to Nrf2 at high doses. CA activated ATF4 in phospho-eIF2α- and heme-regulated inhibitor kinase (HRI)-dependent manners, indicating that CA activates ATF4 through the integrated stress response (ISR) pathway. Furthermore, CA activated Nrf2 and ATF4 cooperatively enhanced the expression of NGF and many antioxidant genes while acting independently to certain client genes. Taken together, these results represent a novel mechanism of CA-mediated gene regulation evoked by Nrf2 and ATF4 cooperation.


Assuntos
Fator 4 Ativador da Transcrição/genética , Citoproteção/genética , Diterpenos de Abietano/farmacologia , Regulação da Expressão Gênica , Fator 2 Relacionado a NF-E2/genética , Fator 4 Ativador da Transcrição/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroquinonas/farmacologia , Modelos Biológicos , Fator 2 Relacionado a NF-E2/metabolismo , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Tunicamicina/farmacologia
5.
Chem Biol Interact ; 306: 104-109, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30998906

RESUMO

Autophagy is a dynamic recycling process that eliminates damaged proteins and cellular organelles to maintain cellular homeostasis. Aldose reductase (AR) catalyzes conversion of glucose to sorbitol. It also catalyzes the reduction of a broad array of saturated and unsaturated aldehydes. Recently we demonstrated that deletion of AR promotes pathological cardiac remodeling via excessive autophagy; however, the role of AR in starvation-induced autophagy has not been determined. To determine the role of AR in starvation-induced autophagy, WTC57/Bl6 mice were pretreated with the AR inhibitor sorbinil (0.2 g/L for 48 h) in drinking water, followed by 24 h fasting. We found that the sorbinil pretreatment in fed mice did not affect blood glucose levels, whereas, it decreased the blood glucose levels in fasting mice. In comparison with fed mice, the LC3II formation and LCII/LCI ratio were increased in the fasted mice hearts and sorbinil pretreatment further enhanced LC3II formation and LC3II/LC3I ratios in these hearts. Fasting-induced autophagy coincided with AMPK activation in the sorbinil pretreated fasted mice hearts. Autophagy and activation of AMPK was also induced in the gastrocnemius skeletal muscle of sorbinil pre-treated fasted mice. Induction of autophagy in the cardiac tissues of sorbinil pretreated fasted mice was accompanied by increased clearance of 4-hydroxytrans-2-nonenal-protein adducts. Taken together, these results indicate that the inhibition of AR during fasting activates autophagic response, increases clearance of aldehyde-protein adducts, which could serve as a mechanism to maintain cellular homeostasis during starvation.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Aldeídos/metabolismo , Autofagia/efeitos dos fármacos , Imidazolidinas/farmacologia , Inanição , Aldeído Redutase/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
Chem Biol Interact ; 307: 58-62, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31026421

RESUMO

After cataract surgery, epithelial cells lining the anterior lens capsule can transition to one of two divergent pathways, including fibrosis which leads to posterior capsular opacification (PCO), or lens fiber cell differentiation which leads to regeneration of lens material. We previously showed that the PCO response can be suppressed with aldose reductase (AR) inhibitors. In this present study we show that AR inhibition, both genetic and pharmacologic with Sorbinil, can augment the process of lens regeneration. Extracapsular lens extraction (ECLE) was carried out in C57BL/6 (WT), AR overexpression (AR-Tg), and AR knockout (ARKO) mice, and in some cases in mice treated with the AR inhibitor sorbinil. Whole eyes were harvested approximately 8 weeks after ECLE and evaluated by histological analysis and immunostaining for the fiber cell marker γ-crystallin. All eyes examined for lens regeneration were paraffin embedded for serial sectioning to produce three-dimensional reconstructed models of lens morphology and size. We observed that AR-null mice respond to ECLE by regenerating a lens-like structure with a circular shape and array of cell nuclei reminiscent of the lens bow region typical of the native mammalian lens. Although WT and AR-Tg eyes also produced some regenerated lens material after ECLE, their structures were consistently smaller than ARKO regenerated lenses. WT mice treated with sorbinil showed higher levels of lens regeneration after ECLE compared to WT mice, as assessed by size and three-dimensional morphology. Altogether, this study adds evidence for a critical role for AR in the response of lens epithelial cells to cataract extraction and lens regeneration.


Assuntos
Aldeído Redutase/metabolismo , Cristalino/fisiologia , Regeneração , Aldeído Redutase/antagonistas & inibidores , Aldeído Redutase/genética , Animais , Extração de Catarata , Inibidores Enzimáticos/farmacologia , Olho/diagnóstico por imagem , Imagem Tridimensional , Imidazolidinas/farmacologia , Cristalino/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regeneração/efeitos dos fármacos
7.
Phytother Res ; 33(6): 1717-1725, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016813

RESUMO

Inflammation is considered to be one of the initial critical factors in the occurrence of calcific heart valve disease. This study was to prove Nobiletin (NBT) inhibits inflammation-caused calcification of human valve interstitial cells (hVICs) and to elucidate the involved molecular mechanisms. Tumor necrosis factor-alpha (TNF-α)-induced hVICs were treated with or without NBT. Cell growth and calcification of hVICs were assessed. RNA sequencing was utilized to investigate the gene expression changes. Molecular target prediction and docking assay were further performed. NBT interfered with hVIC growth under TNF-α condition in a dose-dependent manner also presented a gradual decrease of positive Alizarin Red S staining, down-regulation of BMP2, and RUNX2 gene expression. Based on the global gene expression cluster, control and TNF-α plus NBT group showed a high similarity versus TNF-α only group. After Venn interaction of differential expression genes (DEGs), 2,236 common DEGs were identified to display different biological functions and signaling pathways. ABCG2 and AKR1B1 were further selected as prediction targets of NBT involved in RELA, TNF, BMP2, RUNX2, etc. interactions in mediating hVIC calcification. The results show that NBT is a natural product to prevent the occurrence of heart valve calcification.


Assuntos
Estenose da Valva Aórtica/prevenção & controle , Valva Aórtica/efeitos dos fármacos , Valva Aórtica/patologia , Calcinose/prevenção & controle , Flavonas/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Adulto , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Valva Aórtica/metabolismo , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Calcinose/genética , Calcinose/metabolismo , Calcinose/patologia , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Flavonas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/prevenção & controle , Humanos , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/efeitos adversos
8.
Biomed Pharmacother ; 114: 108794, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30947017

RESUMO

Glycine is a proteinogenic amino acid that serves as a precursor for several proteins. The anti-cataract effects of lysine and other amino acid mixtures in animal models have been reported. Normal rats were administered saline and formed the normal control group (group I). Diabetic rats were administered streptozotocin and were the diabetic control group (group II). Rats were administered glycine (250 mg and 500 mg/kg of body weight) formed groups III and IV, respectively. Diabetic rats were administered sorbinil and were served as positive control (group V). The body weight changes, serum glucose, plasma insulin, total protein, glutathione (GSH) content, and mRNA and protein levels of aldose reductase were determined. Glycine treatment increased body weight gain, reduced blood glucose, and increased plasma insulin levels compared to diabetic control rats, and also increased GSH content and decreased mRNA and protein levels of aldose reductase compared to their respective controls. In summary, glycine supplementation effectively inhibited aldose reductase enzyme activity in experimental diabetic rats.


Assuntos
Catarata/tratamento farmacológico , Complicações do Diabetes/tratamento farmacológico , Diabetes Mellitus Experimental/induzido quimicamente , Glicina/farmacologia , Substâncias Protetoras/farmacologia , Estreptozocina/farmacologia , Aldeído Redutase/metabolismo , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Catarata/sangue , Catarata/etiologia , Catarata/metabolismo , Complicações do Diabetes/sangue , Complicações do Diabetes/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Glutationa/metabolismo , Insulina/sangue , Masculino , Ratos
9.
J Biosci Bioeng ; 128(3): 283-289, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30967334

RESUMO

Candida glycerinogenes, an industrial yeast with excellent multi-stress tolerance, has been applied to glycerol production for decades. However, its genetic manipulation was limited by the absence of meiosis, the diploid genome, and the lack of molecular tools. We described here the implementation of a transient CRISPR-Cas9 system for efficient genome editing in C. glycerinogenes. By targeting the counterselectable marker genes (TRP1, URA3), single and double gene knock-outs were achieved and the auxotroph obtained can be used as a background for targeting other gene (HOG1) at a mutation efficiency of 80%. Further, a xylonic acid producing C. glycerinogenes strain was constructed by knock-in of the xylose dehydrogenase gene, which produced up to 28 g/L ethanol and 9 g/L xylonic acid simultaneously from simulated lignocellulosic hydrolysate (contained 70 g/L glucose and 24 g/L xylose). These results indicated that the CRSIPR-Cas9 system developed here can facilitate the study of gene functions and metabolic pathways in C. glycerinogenes.


Assuntos
Sistemas CRISPR-Cas/genética , Candida/genética , Etanol/metabolismo , Edição de Genes/métodos , Engenharia Metabólica/métodos , Xilose/análogos & derivados , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Candida/metabolismo , Clonagem Molecular/métodos , Técnicas de Inativação de Genes , Glucose/metabolismo , Organismos Geneticamente Modificados , Xilose/metabolismo
10.
Toxicol Lett ; 307: 11-16, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817976

RESUMO

Aldo-Keto Reductase Family 7 Member A2 (AKR7A2) is the most abundant anthracycline metabolizing enzyme in human myocardium. Myocardial AKR7A2 contributes to the synthesis of cardiotoxic C-13 anthracycline alcohol metabolites (e.g., doxorubicinol). The factors that govern the transcription of human AKR7A2 in cardiomyocytes remain largely unexplored. In this study, we performed the functional characterization of the AKR7A2 gene promoter in human AC16 cardiomyocytes. Experiments with gene reporter constructs and chromatin immunoprecipitation assays suggest that NF-κB binds to specific regions in the AKR7A2 promoter. Doxorubicin treatment modified the cellular levels of NF-κB and the expression of AKR7A2. Moreover, doxorubicin treatment led to changes in the pattern of AKR7A2 phosphorylation status. Our results suggest that AKR7A2 expression in human cardiomyocytes is mediated by NF-κB through conserved response elements in the proximal gene promoter region. This study provides the first insights into the functional characteristics of the human AKR7A2 gene promoter.


Assuntos
Aldeído Redutase/metabolismo , Miócitos Cardíacos/metabolismo , Imunoprecipitação da Cromatina , Doxorrubicina/farmacologia , Regulação da Expressão Gênica , Humanos , Miócitos Cardíacos/enzimologia , NF-kappa B/metabolismo , Fosforilação , Regiões Promotoras Genéticas
11.
Nat Commun ; 10(1): 1356, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902987

RESUMO

Isomerases perform biotransformations without cofactors but often cause an undesirable mixture of substrate and product due to unfavorable thermodynamic equilibria. We demonstrate the feasibility of using an engineered yeast strain harboring oxidoreductase reactions to overcome the thermodynamic limit of an isomerization reaction. Specifically, a yeast strain capable of consuming lactose intracellularly is engineered to produce tagatose from lactose through three layers of manipulations. First, GAL1 coding for galactose kinase is deleted to eliminate galactose utilization. Second, heterologous xylose reductase (XR) and galactitol dehydrogenase (GDH) are introduced into the ∆gal1 strain. Third, the expression levels of XR and GDH are adjusted to maximize tagatose production. The resulting engineered yeast produces 37.69 g/L of tagatose from lactose with a tagatose and galactose ratio of 9:1 in the reaction broth. These results suggest that in vivo oxidoreaductase reactions can be employed to replace isomerases in vitro for biotransformation.


Assuntos
Biotransformação , Saccharomyces cerevisiae/metabolismo , Aldeído Redutase/metabolismo , Reatores Biológicos/microbiologia , Galactose/metabolismo , Dosagem de Genes , Hexoses/metabolismo , Espaço Intracelular/metabolismo , Isomerismo , Lactose/metabolismo , Modelos Biológicos , Oxirredução , Oxirredutases/metabolismo , Desidrogenase do Álcool de Açúcar/metabolismo , Termodinâmica , Xilose/metabolismo
12.
Eur J Med Chem ; 168: 154-175, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30818176

RESUMO

A novel class of spiroimidazolidine-2',4'-diones substituted with aryl sulfonyl group at different positions was designed and synthesized. The target compounds were evaluated for their potential to release insulin from MIN6 cell line derived from in-vivo immortalized insulin-secreting pancreatic cells. The MIN6 cells represent an important model of beta cells, which as passage numbers increases, lose the first phase but retain partial second phase glucose stimulated insulin secretion (GSIS), similar to patients in early type 2 diabetes onset. Some of the compounds exhibited high potency. Compound 2d and 3f exhibited excellent insulin release activity from MIN6 cells when compared with standard drug, tolbutamide. Some of these compounds had a potent inhibitory activity for human recombinant aldose reductase (ALR2), an enzyme which converts glucose into sorbitol and plays a key role in development of complications arising from diabetes, such as retinopathy, nephropathy, neuropathy and cataract formation. Against human recombinant ALR2, compounds 2a, 3a-d, and 3f-h displayed effective inhibition activities. The results were augmented by the ability of the compounds to prevent sorbitol accumulation in the isolated rat lenses, sciatic nerves and erythrocytes. Some of the compounds were found to possess excellent dual activity, hence they may be promising candidates to modify and evaluate their dual action, i.e., insulin release to combat diabetes and ALR2 inhibition to prevent/treat diabetic complications. The compounds were also found to possess good antioxidant efficacy. Furthermore, most of the compounds lack toxicity as determined on human embryonic kidney cell lines 293 (HEK293).


Assuntos
Aldeído Redutase/antagonistas & inibidores , Antioxidantes/farmacologia , Imidazóis/farmacologia , Insulina/metabolismo , Sorbitol/metabolismo , Compostos de Espiro/farmacologia , Aldeído Redutase/química , Aldeído Redutase/metabolismo , Animais , Antioxidantes/síntese química , Antioxidantes/química , Células Cultivadas , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Células HEK293 , Humanos , Imidazóis/síntese química , Imidazóis/química , Camundongos , Modelos Moleculares , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Ratos , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
13.
Toxicon ; 161: 57-64, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30831148

RESUMO

Venom from the parasitoid wasp Nasonia vitripennis dramatically elevates sorbitol levels in its natural fly hosts. In humans, sorbitol elevation is associated with complications of diabetes. Here we demonstrate that venom also induces this disease-relevant phenotype in human cells, and investigate possible pathways involved. Key findings are that (a) low doses of Nasonia venom elevate sorbitol levels in human renal mesangial cells (HRMCs) without changing glucose or fructose levels; (b) venom is a much more potent inducer of sorbitol elevation than glucose; (c) low venom doses significantly alter expression of genes involved in sterol and alcohol metabolism, transcriptional regulation, and chemical/stimulus response; (d) although venom treatment does not alter expression of the key sorbitol pathway gene aldose reductase (AR); (e) venom elevates expression of a related gene implicated in diabetes complications (AKR1C3) as well as the fructose metabolic gene (GFPT2). Although elevated sorbitol is accepted as a major contributor to secondary complications of diabetes, the molecular mechanism of sorbitol regulation and its contribution to diabetes complications are not fully understood. Our findings suggest that genes other than AR could contribute to sorbitol regulation, and more broadly illustrate the potential of parasitoid venoms for medical application.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Células Mesangiais/efeitos dos fármacos , Sorbitol/metabolismo , Venenos de Vespas/farmacologia , Aldeído Redutase/metabolismo , Membro C3 da Família 1 de alfa-Ceto Redutase/metabolismo , Animais , Contagem de Células , Frutose/metabolismo , Glucose/metabolismo , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Humanos , Rim/citologia , Rim/metabolismo , Células Mesangiais/metabolismo , Cultura Primária de Células
14.
Bioresour Technol ; 281: 374-381, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30831517

RESUMO

In this study, the xylose reductase gene (XRTL) from Thermomyces lanuginosus SSBP was expressed in Pichia pastoris GS115 and Saccharomyces cerevisiae Y294. The purified 39.2 kDa monomeric enzyme was optimally active at pH 6.5 and 50 °C and showed activity over a wide range of temperatures (30-70 °C) and pH (4.0-9.0), with a half-life of 1386 min at 50 °C. The enzyme preferred NADPH as cofactor and showed broad substrate specificity. The enzyme was inhibited by Cu2+, Fe2+ and Zn2+, while ferulic acid was found to be the most potent lignocellulosic inhibitor. Recombinant S. cerevisiae with the XRTL gene showed 34% higher xylitol production than the control strain. XRTL can therefore be used in a cell-free xylitol production process or as part of a pathway for utilization of xylose from lignocellulosic waste.


Assuntos
Aldeído Redutase/metabolismo , Eurotiales/enzimologia , Lignina/metabolismo , Aldeído Redutase/antagonistas & inibidores , Aldeído Redutase/genética , NADP/metabolismo , Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato , Xilitol/biossíntese , Xilose/metabolismo
15.
Chem Biol Interact ; 302: 36-45, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30707979

RESUMO

Aldose reductase (AR), a member of aldo-keto reductase family, is the rate-limiting enzyme in the polyol pathway, and is known to play a key role in the pathogenesis of diabetic complications. AR also catalyzes the reduction of reactive aldehydes, thereby detoxifying endogenous as well as xenobiotic aldehydes in various tissues. The transcription of the AR gene was previously shown to be augmented by various stimuli including osmotic and oxidative stresses. A highly conserved region composed of an antioxidant response element (ARE), AP-1 site, and tonicity responsive enhancer (TonE) has been identified within the 5'-flanking region of the AR genes of humans, rats, and mice, which we designated as the multiple stress response region (MSRR). We previously showed that the transcription factor Nrf2 activated AR transcription via ARE within MSRR. In the present study, we examined the interactions among Nrf2, c-Jun, and the TonE-binding protein (TonEBP) in the regulation of AR gene transcription. In gene reporter assays using luciferase reporter constructs containing the MSRR of the mouse AR (AKR1B3) gene with HepG2 cells, the forced expression of Nrf2 or TonEBP significantly increased promoter activity. The synergistic augmentation of promoter activity was observed when Nrf2 and TonEBP were co-introduced. On the other hand, the co-expression of c-Jun repressed promoter activation by Nrf2 and TonEBP. The mutation of the AP-1 site within MSRR did not affect the repressive effects of c-Jun, while the introduction of truncated c-Jun proteins lacking the leucine zipper domain no longer suppressed Nrf2-or TonEBP-mediated transactivation, suggesting that c-Jun repressed promoter activity independently of the AP-1 site and that interactions with protein factors via the leucine zipper domain were necessary for its negative effects on Nrf2 and TonEBP. These results indicate that AR promoter activity is cooperatively regulated by multiple transcription factors via MSRR.


Assuntos
Aldeído Redutase/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fatores de Transcrição NFATC/metabolismo , Aldeído Redutase/genética , Animais , Genes Reporter , Células Hep G2 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Camundongos , Mutagênese Sítio-Dirigida , Fator 2 Relacionado a NF-E2/genética , Fatores de Transcrição NFATC/genética , Fosforilação , Plasmídeos/genética , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Transcrição Genética
16.
J Enzyme Inhib Med Chem ; 34(1): 350-360, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30734590

RESUMO

Seven triterpenoid saponins were identified in methanolic extracts of seeds of the Zolfino bean landrace (Phaseolus vulgaris L.) by HPLC fractionation, revealing their ability to inhibit highly purified human recombinant aldose reductase (hAKR1B1). Six of these compounds were associated by MS analysis with the following saponins already reported in different Phaseolus vulgaris varieties: soyasaponin Ba (V), soyasaponin Bb, soyasaponin Bd (sandosaponin A), soyasaponin αg, 3-O-[R-l-rhamnopyranosyl(1 → 2)-α-d-glucopyranosyl(1 → 2)-α-d-glucuronopyranosyl]olean-12-en-22-oxo-3α,-24-diol, and soyasaponin ßg. The inhibitory activity of the collected fractions containing the above compounds was tested for hAKR1B1-dependent reduction of both l-idose and 4-hydroxynonenal, revealing that some are able to differentially inhibit the enzyme. The present work also highlights the difficulties in the search for aldose reductase differential inhibitors (ARDIs) in mixtures due to the masking effect on ARDIs exerted by the presence of conventional aldose reductase inhibitors. The possibility of differential inhibition generated by a different inhibitory model of action of molecules on different substrates undergoing transformation is also discussed.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Phaseolus/química , Saponinas/farmacologia , Sementes/química , Triterpenos/farmacologia , Aldeído Redutase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Conformação Molecular , Saponinas/química , Saponinas/isolamento & purificação , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
17.
Expert Opin Ther Pat ; 29(3): 199-213, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30760060

RESUMO

INTRODUCTION: Aldose reductase (ALR2) is both the key enzyme of the polyol pathway, whose activation under hyperglycemic conditions leads to the development of chronic diabetic complications, and the crucial promoter of inflammatory and cytotoxic conditions, even under a normoglycemic status. Accordingly, it represents an excellent drug target and a huge effort is being done to disclose novel compounds able to inhibit it. AREAS COVERED: This literature survey summarizes patents and patent applications published over the last 5 years and filed for natural, semi-synthetic and synthetic ALR2 inhibitors. Compounds described have been discussed and analyzed from both chemical and functional angles. EXPERT OPINION: Several ALR2 inhibitors with a promising pre-clinical ability to address diabetic complications and inflammatory diseases are being developed during the observed timeframe. Natural compounds and plant extracts are the prevalent ones, thus confirming the use of phytopharmaceuticals as an increasingly pursued therapeutic trend also in the ALR2 inhibitors field. Intriguing hints may be taken from synthetic derivatives, the most significant ones being represented by the differential inhibitors ARDIs. Differently from classical ARIs, these compounds should fire up the therapeutic efficacy of the class while minimizing its side effects, thus overcoming the existing limits of this kind of inhibitors.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Desenho de Drogas , Inibidores Enzimáticos/farmacologia , Aldeído Redutase/metabolismo , Animais , Complicações do Diabetes/tratamento farmacológico , Complicações do Diabetes/enzimologia , Inibidores Enzimáticos/efeitos adversos , Humanos , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Patentes como Assunto
18.
J Biol Chem ; 294(11): 4272-4281, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30651350

RESUMO

Dietary, fructose-containing sugars have been strongly associated with the development of nonalcoholic fatty liver disease (NAFLD). Recent studies suggest that fructose also can be produced via the polyol pathway in the liver, where it may induce hepatic fat accumulation. Moreover, fructose metabolism yields uric acid, which is highly associated with NAFLD. Here, using biochemical assays, reporter gene expression, and confocal fluorescence microscopy, we investigated whether uric acid regulates aldose reductase, a key enzyme in the polyol pathway. We evaluated whether soluble uric acid regulates aldose reductase expression both in cultured hepatocytes (HepG2 cells) and in the liver of hyperuricemic rats and whether this stimulation is associated with endogenous fructose production and fat accumulation. Uric acid dose-dependently stimulated aldose reductase expression in the HepG2 cells, and this stimulation was associated with endogenous fructose production and triglyceride accumulation. This stimulatory mechanism was mediated by uric acid-induced oxidative stress and stimulation of the transcription factor nuclear factor of activated T cells 5 (NFAT5). Uric acid also amplified the effects of elevated glucose levels to stimulate hepatocyte triglyceride accumulation. Hyperuricemic rats exhibited elevated hepatic aldose reductase expression, endogenous fructose accumulation, and fat buildup that was significantly reduced by co-administration of the xanthine oxidase inhibitor allopurinol. These results suggest that uric acid generated during fructose metabolism may act as a positive feedback mechanism that stimulates endogenous fructose production by stimulating aldose reductase in the polyol pathway. Our findings suggest an amplifying mechanism whereby soft drinks rich in glucose and fructose can induce NAFLD.


Assuntos
Tecido Adiposo/metabolismo , Aldeído Redutase/metabolismo , Frutose/biossíntese , Hepatopatia Gordurosa não Alcoólica/metabolismo , Polímeros/metabolismo , Ácido Úrico/farmacologia , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Frutose/metabolismo , Células Hep G2 , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Polímeros/análise , Ratos , Ratos Wistar , Células Tumorais Cultivadas , Ácido Úrico/metabolismo
19.
Int J Mol Sci ; 20(1)2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30621365

RESUMO

While in search of an enzyme for the conversion of xylose to xylitol at elevated temperatures, a xylose reductase (XR) gene was identified in the genome of the thermophilic fungus Chaetomium thermophilum. The gene was heterologously expressed in Escherichia coli as a His6-tagged fusion protein and characterized for function and structure. The enzyme exhibits dual cofactor specificity for NADPH and NADH and prefers D-xylose over other pentoses and investigated hexoses. A homology model based on a XR from Candida tenuis was generated and the architecture of the cofactor binding site was investigated in detail. Despite the outstanding thermophilicity of its host the enzyme is, however, not thermostable.


Assuntos
Aldeído Redutase/química , Aldeído Redutase/metabolismo , Chaetomium/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Coenzimas/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/isolamento & purificação , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Especificidade por Substrato , Temperatura Ambiente
20.
Curr Protein Pept Sci ; 20(1): 92-110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30264677

RESUMO

Diabetic retinopathy (DR) remains the leading cause of blindness in working-aged adults around the world. The proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME) are the severe vision threatening stages of the disorder. Although, a huge body of research exists in elaborating the pathological mechanisms that lead to the development of DR, the certainty and the correlation amongst these pathways remain ambiguous. The complexity of DR lies in the multifactorial pathological perturbations that are instrumental in both the disease development and its progression. Therefore, a holistic perspective with an understanding of these pathways and their correlation may explain the pathogenesis of DR as a unifying mechanism. Hyperglycemia, oxidative stress and inflammatory pathways are the crucial components that are implicated in the pathogenesis of DR. Of these, hyperglycemia appears to be the initiating central component around which other pathological processes operate. Thus, this review discusses the role of hyperglycemia, oxidative stress and inflammation in the pathogenesis of DR, and highlights the cross-talk amongst these pathways in an attempt to understand the complex interplay of these mechanisms. Further, an effort has been made to identify the knowledge gap and the key players in each pathway that may serve as potential therapeutic drug targets.


Assuntos
Diabetes Mellitus/genética , Retinopatia Diabética/genética , Produtos Finais de Glicação Avançada/genética , Hiperglicemia/genética , Neovascularização Patológica/genética , Estresse Oxidativo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Glicemia/metabolismo , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Progressão da Doença , Regulação da Expressão Gênica , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Inflamação , Redes e Vias Metabólicas , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Transdução de Sinais
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