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1.
Chemosphere ; 240: 124914, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31557642

RESUMO

Arsenic (As) contamination is one of the most daunting environmental problem bothering the whole world. Exploring a suitable bioremediation technique is an urgent need of the hour. The present study focusses on scrutinizing the ectomycorrhizal (ECM) fungus for its potential role in As detoxification and understanding the molecular mechanisms responsible for its tolerance. When exposed to increasing concentrations of external As, the ECM fungus H. cylindrosporum accumulated the metalloid intracellularly, inducing the glutathione biosynthesis pathway. The genes coding for GSH biosynthesis enzymes, γ-glutamylcysteine synthetase (Hcγ-GCS) and glutathione synthetase (HcGS) were highly regulated by As stress. Arsenic coordinately upregulated the expression of both Hcγ-GCS and HcGS genes, thus resulting in increased Hcγ-GCS and HcGS protein expressions and enzyme activities, with substantial increase in intracellular GSH. Functional complementation of the two genes (Hcγ-GCS and HcGS) in their respective yeast mutants (gsh1Δ and gsh2Δ) further validated the role of both enzymes in mitigating As toxicity. These findings clearly highlight the potential importance of GSH antioxidant defense system in regulating the As induced responses and its detoxification in ECM fungus H. cylindrosporum.


Assuntos
Arsênico/toxicidade , Glutationa/biossíntese , Hebeloma/efeitos dos fármacos , Micorrizas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Arsênico/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Teste de Complementação Genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Hebeloma/genética , Hebeloma/metabolismo , Inativação Metabólica , Mutação , Micorrizas/genética , Micorrizas/metabolismo , Saccharomyces cerevisiae/metabolismo , Poluentes do Solo/metabolismo
2.
Adv Clin Exp Med ; 28(12): 1609-1614, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31851788

RESUMO

BACKGROUND: During cerebral ischemia, energy restoration through the regulation of glucose transporters and antioxidant defense mechanisms is essential to maintain cell viability. Antioxidant therapy has been considered effective to attenuate brain damage; moreover, the regulation of transcription factors that positively regulate the expression of glucose transporters is associated with this therapy. Recently, it has been reported that the use of antioxidants such as S-allylcysteine (SAC), a component of aged garlic extract (AGE), improves survival in experimental models of cerebral ischemia. OBJECTIVES: The aim of this study was to determine the effect of AGE and SAC on the level of mRNA expression of the main neuronal glucose transporter (GLUT3) and the glutamate cysteine ligase catalytic subunit (GCLC) in rats with transient focal cerebral ischemia. MATERIAL AND METHODS: Cerebral ischemia was induced in male Wistar rats by middle cerebral artery occlusion (MCAO) for 2 h. The animals were sacrificed after different reperfusion times (0-48 h). Animals injected with AGE (360 mg/kg, intraperitoneally (i.p.)) and SAC (300 mg/kg, i.p.) at the beginning of reperfusion were sacrificed after 2 h. The mRNA expression level was analyzed in the fronto-parietal cortex using quantitative polymerase chain reaction (qPCR). RESULTS: Two major increases in GLUT3 expression at 1 h and 24 h of reperfusion were found. Both treatments increased GLUT3 and GCLC mRNA levels in control and under ischemic/reperfusion injury animals. CONCLUSIONS: This data suggests that SAC and AGE might induce neuroprotection, while controlling reactive oxygen species (ROS) levels, as indicated by the increase in GCLC expression, and regulating the energy content of the cell by increasing glucose transport mediated by GLUT3.


Assuntos
Isquemia Encefálica , Alho , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Fármacos Neuroprotetores , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Isquemia Encefálica/metabolismo , Cisteína/análogos & derivados , Cisteína/farmacologia , Alho/química , Proteínas Facilitadoras de Transporte de Glucose/efeitos dos fármacos , Glutamato-Cisteína Ligase/efeitos dos fármacos , Masculino , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo
3.
Biosci Biotechnol Biochem ; 83(12): 2202-2212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31409200

RESUMO

In this study, we isolated eight phenylethanoid glycosides from Paraboea martinii for the first time, and evaluated the mechanism underlying their neuroprotective effects against H2O2-induced injury in PC12 cells. The MTS method was utilized to screen the phenylethanoid glycosides for protective ability. Next, qRT-PCR and western blotting analysis were used to detect the transcription levels of HO-1 and GCLC, which are regulated by Nrf2. The inhibitor ZnPP was used to analyze the involvement of Nrf2 in HO-1 expression. Analyses showed that caleolarioside B, paraboside B, and paraboside II also upregulated the expression of HO-1, but showed no obvious effect on GCLC. Pretreatment with ZnPP significantly reduced the neuroprotective effects. Thus, phenylethanoid glycosides isolated from P. martinii protected PC12 cells from H2O2-induced damage by upregulating HO-1. The results provided evidence that P. martinii might be a potential therapeutic agent for the treatment of neurodegenerative diseases.


Assuntos
Glicosídeos/farmacologia , Peróxido de Hidrogênio/toxicidade , Fármacos Neuroprotetores/farmacologia , Feocromocitoma/patologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células PC12 , Ratos , Transcrição Genética/efeitos dos fármacos
4.
BMC Complement Altern Med ; 19(1): 139, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221142

RESUMO

BACKGROUND: Several studies have found that caffeic acid (CA), a well-known phytochemical, displays important antioxidant and anti-cancer activities. However, no evidence exists on the protective effect and its mechanisms that CA treatment alone has against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells. METHODS: Hepatoprotective activities such as cell viability, mRNA expression, and report gene assay were measured using HepG2 cell. Three types of genes and proteins related with detoxification in liver were used for measuring the hepatoprotective effects. Statistical analysis was performed using one-way ANOVA test and differences among groups were evaluated by Tukey's studentized range tests. RESULTS: The present study indicate that treatment with CA up-regulates heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) mRNA and protein expressions in a CA-dose-dependent manner. In addition, translocation of nuclear factor-E2 p45-related factor (Nrf2) from the cytoplasm to the nucleus and phosphorylation of extracellular signal-regulated kinase, ERK and c-Jun N-terminal kinase, JNK which have been shown to be involved in mitogen-activated protein kinases, MAPKs are significantly enhanced by CA treatment. Furthermore, in cell nuclei, CA enhances the 5'-flanking regulatory region of human antioxidant response element (ARE) and activates the ARE binding site. CONCLUSION: Therefore, CA proved to be a stimulant of the expression of detoxification enzymes such as HO-1, GCLC, and GCLM through the ERK/Nrf2 pathway, and it may be an effective chemoprotective agent for protecting liver damage against oxidative damage.


Assuntos
Ácidos Cafeicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , terc-Butil Hidroperóxido/toxicidade , Elementos de Resposta Antioxidante/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
Redox Biol ; 26: 101231, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31203195

RESUMO

Trypanothione (T(SH)2) is the main antioxidant metabolite for peroxide reduction in Trypanosoma cruzi; therefore, its metabolism has attracted attention for therapeutic intervention against Chagas disease. To validate drug targets within the T(SH)2 metabolism, the strategies and methods of Metabolic Control Analysis and kinetic modeling of the metabolic pathway were used here, to identify the steps that mainly control the pathway fluxes and which could be appropriate sites for therapeutic intervention. For that purpose, gamma-glutamylcysteine synthetase (γECS), trypanothione synthetase (TryS), trypanothione reductase (TryR) and the tryparedoxin cytosolic isoform 1 (TXN1) were separately overexpressed to different levels in T. cruzi epimastigotes and their degrees of control on the pathway flux as well as their effect on drug resistance and infectivity determined. Both experimental in vivo as well as in silico analyses indicated that γECS and TryS control T(SH)2 synthesis by 60-74% and 15-31%, respectively. γECS overexpression prompted up to a 3.5-fold increase in T(SH)2 concentration, whereas TryS overexpression did not render an increase in T(SH)2 levels as a consequence of high T(SH)2 degradation. The peroxide reduction flux was controlled for 64-73% by TXN1, 17-20% by TXNPx and 11-16% by TryR. TXN1 and TryR overexpression increased H2O2 resistance, whereas TXN1 overexpression increased resistance to the benznidazole plus buthionine sulfoximine combination. γECS overexpression led to an increase in infectivity capacity whereas that of TXN increased trypomastigote bursting. The present data suggested that inhibition of high controlling enzymes such as γECS and TXN1 in the T(SH)2 antioxidant pathway may compromise the parasite's viability and infectivity.


Assuntos
Antioxidantes/metabolismo , Glutamato-Cisteína Ligase/genética , Glutationa/análogos & derivados , Proteínas de Protozoários/genética , Espermidina/análogos & derivados , Tiorredoxinas/genética , Trypanosoma cruzi/efeitos dos fármacos , Amida Sintases/genética , Amida Sintases/metabolismo , Butionina Sulfoximina/farmacologia , Linhagem Celular , Combinação de Medicamentos , Resistência a Medicamentos/genética , Fibroblastos/parasitologia , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/metabolismo , Glutationa/antagonistas & inibidores , Glutationa/biossíntese , Humanos , Peróxido de Hidrogênio/farmacologia , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , Nitroimidazóis/farmacologia , Oxirredução , Estresse Oxidativo , Peroxidases/genética , Peroxidases/metabolismo , Proteínas de Protozoários/metabolismo , Transdução de Sinais , Espermidina/antagonistas & inibidores , Espermidina/biossíntese , Tiorredoxinas/metabolismo , Tripanossomicidas/farmacologia , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/genética
6.
Free Radic Res ; 53(7): 791-799, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31198069

RESUMO

Oxidative stress caused as a result of iron overload is implicated in clinical manifestation of beta-thalassemia/haemoglobin E (ß-Thal/HbE). In this study, we investigated the cellular adaptation against oxidative stress in ß-Thal/HbE patients. Twenty-four paediatric ß-Thal/HbE patients and 22 healthy controls were recruited in the study. Blood samples from patients exhibited iron overload, elevation of lipid peroxidation, and marked diminution in the reduced glutathione (GSH) level. However, expression of glutamate-cysteine ligase catalytic (GCLC) subunit, a key enzyme in GSH biosynthesis, was up-regulated when compared with that in controls. GCLC protein levels were correlated with serum iron. There was an enhanced binding activity of the oligonucleotide probe for Nrf2-driven antioxidant response element (ARE) to nuclear protein from blood mononuclear cells of thalassemia subjects. In conclusion, ß-Thal/HbE patients exhibit elevated plasma levels of GCLC expression and Nrf2-ARE binding activity, which may account for their adaptive survival response to oxidative stress.


Assuntos
Glutamato-Cisteína Ligase/metabolismo , Sobrecarga de Ferro/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Talassemia beta/metabolismo , Adolescente , Criança , Feminino , Humanos , Sobrecarga de Ferro/sangue , Masculino , Fator 2 Relacionado a NF-E2/sangue , Regulação para Cima , Talassemia beta/sangue
7.
Int J Mol Sci ; 20(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108850

RESUMO

Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease resulting in the destruction of insulin producing ß-cells of the pancreas, with consequent insulin deficiency and excessive glucose production. Hyperglycemia results in increased levels of reactive oxygen species (ROS) and nitrogen species (RNS) with consequent oxidative/nitrosative stress and tissue damage. Oxidative damage of the pancreatic tissue may contribute to endothelial dysfunction associated with diabetes. The aim of the present study was to investigate if the potentially protective effects of phenethyl ester of caffeic acid (CAPE), a natural phenolic compound occurring in a variety of plants and derived from honeybee hive propolis, and of a novel CAPE analogue, as heme oxygenase-1 (HO-1) inducers, could reduce pancreatic oxidative damage induced by excessive amount of glucose, affecting the nitric oxide synthase/dimethylarginine dimethylaminohydrolase (NOS/DDAH) pathway in streptozotocin-induced type 1 diabetic rats. Our data demonstrated that inducible nitric oxide synthase/gamma-Glutamyl-cysteine ligase (iNOS/GGCL) and DDAH dysregulation may play a key role in high glucose mediated oxidative stress, whereas HO-1 inducers such as CAPE or its more potent derivatives may be useful in diabetes and other stress-induced pathological conditions.


Assuntos
Antioxidantes/administração & dosagem , Ácidos Cafeicos/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Heme Oxigenase (Desciclizante)/metabolismo , Álcool Feniletílico/análogos & derivados , Amidoidrolases/metabolismo , Animais , Antioxidantes/farmacologia , Ácidos Cafeicos/farmacologia , Diabetes Mellitus Experimental/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/farmacologia , Própole/química , Ratos , Ratos Wistar , Estreptozocina , Regulação para Cima
8.
Biofactors ; 45(4): 563-574, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31131946

RESUMO

Isoflavones are one group of the major flavonoids and possess multiple biological activities due to their antioxidant properties. However, a clear antioxidant mechanism of dietary isoflavones is still remained to be answered. In this study, the effects of isoflavones on the nuclear factor E2-related factor 2 (Nrf2)-antioxidant response element (ARE) signaling pathway and the underlying molecular mechanisms were investigated. Results showed that isoflavones are potential Nrf2-ARE activators while their activities were structure dependent. Biochanin A (BCA), an O-methylated isoflavone with low direct antioxidant activity, can effectively protect HepG2 cells against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage via activation of the Nrf2 signaling, and thereby the induction of downstream cytoprotective enzymes including NAD(P)H quinone oxidoreductase-1, heme oxygenasae-1, and glutamate-cysteine ligase catalytic subunit. A molecular docking study revealed that BCA could directly bind into the pocket of Kelch-like erythroid cell-derived protein with CNC homology (ECH)-associated protein 1 (Keap1), a cytoplasmic suppressor of Nrf2, to facilitate Nrf2 activation. The upstream mitogen-activated protein kinase (MAPK) pathways were also involved in the activation of Nrf2 signaling. These findings indicate that the protective actions of dietary isoflavones against oxidative damage may be at least partly due to their ability to enhance the intracellular antioxidant response system by modulating the Nrf2-ARE signaling pathway.


Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/farmacologia , Genisteína/farmacologia , Proteínas Quinases Ativadas por Mitógeno/genética , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/metabolismo , Oxidantes/antagonistas & inibidores , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , terc-Butil Hidroperóxido/antagonistas & inibidores , terc-Butil Hidroperóxido/farmacologia
9.
Molecules ; 24(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018491

RESUMO

This study aimed to investigate the antioxidant activity and release behavior of anthocyanin (ANC) loaded within FA-g-MD wall (ANC-FA-g-MD microcapsule) in vitro. The microencapsulation of ANC was prepared by spray drying and displayed a biphasic release profile. The combination of ANC and FA-g-MD (0.0625-1 mg/mL) showed a higher antioxidant activity than that of both individuals. A possible intermolecular interaction between ANC and FA-g-MD was studied by UV-vis spectra. Intracellular reactive oxygen species (ROS), 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) test, and protein expression of quinone oxidoreductase 1(NQO1), glutathione reductase (GSR) and γ-glutamate cysteine ligase catalytic subunit (γ-GCLC) were measured through human colon cancer cells (HT-29). After a 24-hour incubation of the HT-29, the combinations (0-60 µg/mL) exhibited a high potential to diminish the ROS level. And the distinct upregulated expressions of GCLC and NQO1 of HT-29 were detected after treatment with combinations compared to those of single ones. These results suggested that the ANC-FA-g-MD microcapsules exerts enhanced antioxidant effect with capability of the modulation of GCLC and NQO1.


Assuntos
Antocianinas/farmacologia , Cápsulas/síntese química , Ácidos Cumáricos/química , Portadores de Fármacos , Depuradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Polissacarídeos/química , Antocianinas/química , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos/métodos , Ativação Enzimática/efeitos dos fármacos , Depuradores de Radicais Livres/química , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Células HT29 , Humanos , Peróxido de Hidrogênio/farmacologia , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Subunidades Proteicas/agonistas , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo
10.
Biochem J ; 476(7): 1191-1203, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877193

RESUMO

Plant γ-glutamylcysteine ligase (GCL), catalyzing the first and tightly regulated step of glutathione (GSH) biosynthesis, is redox-activated via formation of an intramolecular disulfide bond. In vitro, redox-activation of recombinant GCL protein causes formation of homo-dimers. Here, we have investigated whether dimerization occurs in vivo and if so whether it contributes to redox-activation. FPLC analysis indicated that recombinant redox-activated WT (wild type) AtGCL dissociates into monomers at concentrations below 10-6 M, i.e. below the endogenous AtGCL concentration in plastids, which was estimated to be in the micromolar range. Thus, dimerization of redox-activated GCL is expected to occur in vivo To determine the possible impact of dimerization on redox-activation, AtGCL mutants were generated in which salt bridges or hydrophobic interactions at the dimer interface were interrupted. WT AtGCL and mutant proteins were analyzed by non-reducing SDS-PAGE to address their redox state and probed by FPLC for dimerization status. Furthermore, their substrate kinetics (K M, V max) were compared. The results indicate that dimer formation is not required for redox-mediated enzyme activation. Also, crystal structure analysis confirmed that dimer formation does not affect binding of GSH as competitive inhibitor. Whether dimerization affects other enzyme properties, e.g. GCL stability in vivo, remains to be investigated.


Assuntos
Proteínas de Arabidopsis/metabolismo , Glutamato-Cisteína Ligase/química , Glutamato-Cisteína Ligase/metabolismo , Glutationa/biossíntese , Sequência de Aminoácidos , Substituição de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Domínio Catalítico , Ativação Enzimática , Glutamato-Cisteína Ligase/genética , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Oxirredução , Plantas Geneticamente Modificadas , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
11.
Biomed Pharmacother ; 111: 1166-1175, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30841430

RESUMO

Diabetic nephropathy (DN) is one of the most common diabetic complications, and alpha-carbonyl aldehydes and their detoxicating enzyme glyoxalase 1 (Glo-1) play vital roles in pathogenesis of diabetic complications. The aim of this study was to evaluate the renoprotective effects of hesperetin against DN in rats, and to investigate mechanisms from the aspect of Nrf2/ARE/Glo-1 pathway. Streptozotocin-induced diabetic rats were treated orally with hesperetin (50 and 150 mg/kg), or nuclear factor erythroid-derived-2-like 2 (Nrf2) inducer tert-butylhydroquinone (tBHQ, 25 mg/kg) for 10 weeks. Then proteinuria, creatinine, urea nitrogen, and uric acid were assayed for renal functions, fibronectin and collagen IV levels by immunohistochemistry, as well as periodic acid-Schiff staining and electron microscope observation, were used to assess renal morphology. Glo-1 activity, protein, and mRNA levels and the classic Nrf2/ARE pathway were investigated. Moreover, advanced glycation endproducts (AGEs) and its receptor RAGE, interleukin-1ß and tumor necrosis factor-α levels were also examined in the kidney. Hesperetin markedly ameliorated the renal functions and structural changes of diabetic rats, accompanied by up-regulation of Glo-1 as well as inhibition of AGEs/RAGE axis and inflammation. Meanwhile, hesperetin caused significant increases in Nrf2 and p-Nrf2 levels, as well as up-regulation of γ-glutamylcysteine synthetase, a well-known target gene of Nrf2/ARE signaling. Our results demonstrated that hesperetin could slow down the pathological process of DN, and Glo-1 enhancement contributed to the beneficial effects, which was obtained by the activation of Nrf2/ARE pathway.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Hesperidina/farmacologia , Lactoilglutationa Liase/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Estreptozocina/farmacologia , Regulação para Cima/efeitos dos fármacos
12.
Molecules ; 24(4)2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781396

RESUMO

Fisetin, a dietary flavonoid, is reported to have cellular antioxidant activity with an unclear mechanism. In this study, we investigated the effect of fisetin on the nuclear factor, erythroid 2-like 2 (Nrf2) signaling pathway in HepG2 cells to explore the cellular antioxidant mechanism. Fisetin upregulated the mRNA expression of heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), glutamate-cysteine ligase modifier subunit (GCLM), and NAD(P)H quinone oxidoreductase-1 (NQO1), and induced the protein of HO-1 but had no significant effect on the protein of GCLC, GCLM and NQO1. Moreover, nuclear accumulation of Nrf2 was clearly observed by immunofluorescence analysis and western blotting after fisetin treatment, and an enhanced luciferase activity of antioxidant response element (ARE)-regulated transactivation was obtained by dual-luciferase reporter gene assays. In addition, fisetin upregulated the protein level of Nrf2 and downregulated the protein level of Kelch-like ECH-associated protein 1 (Keap1). However, fisetin had no significant effect on Nrf2 mRNA expression. When protein synthesis was inhibited with cycloheximide (CHX), fisetin prolonged the half-life of Nrf2 from 15 min to 45 min. When blocking Nrf2 degradation with proteasome inhibitor MG132, ubiquitinated proteins were enhanced, and fisetin reduced ubiquitination of Nrf2. Taken together, fisetin translocated Nrf2 into the nucleus and upregulated the expression of downstream HO-1 gene by inhibiting the degradation of Nrf2 at the post-transcriptional level. These data provide the molecular mechanism to understand the cellular antioxidant activity of fisetin.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Elementos de Resposta Antioxidante/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
13.
Biomed Res Int ; 2019: 2692970, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800665

RESUMO

In previous studies, Gentianella acuta (Michx.) Hulten was reported to contain xanthones, iridoids, terpenoids, and sterols and is mainly used to cure hepatitis, jaundice, fever, headache, and angina pectoris. In this study, we used bioassay guided fractionation to identify compounds from G. acuta and investigated their activity against hydrogen peroxide (H2O2)-induced apoptosis of H9c2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic (GCLC) expression were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was evaluated using western blot. The results showed that all four compounds had protective effects on H9c2 cells. The transcription levels of HO-1 and GCLC significantly increased in H9c2 cells pretreated with norswertianolin (1), swetrianolin (2), demethylbellidifolin (3), and bellidifolin (4). However, compared to the model group, the transcription levels of Nrf2 were not enhanced by pretreatment with compounds 1, 2, and 4. The protein expression levels of HO-1 and GCLC in H9c2 cells were greater than that in the H2O2-treated group, and the expression of Nrf2 was not significantly changed except by swetrianolin treatment; inhibitors can reverse the protective effect by ZnPP (15 µM), BSO (10 µM), and brusatol (10 µM). The results indicated that the four compounds isolated from G. acuta inhibited the oxidative injury induced by H2O2 by activating the Nrf2/ARE pathway in H9c2 cells and provide evidence that G. acuta may be a potential therapeutic agent for the treatment of cardiovascular diseases.


Assuntos
Gentianella/química , Peróxido de Hidrogênio/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Transcrição Genética/efeitos dos fármacos , Xantenos/farmacologia , Xantonas/farmacologia
14.
Oxid Med Cell Longev ; 2019: 7945983, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30805084

RESUMO

Background: Aurothioglucose- (ATG-) mediated inhibition of thioredoxin reductase-1 (TXNRD1) improves alveolarization in experimental murine bronchopulmonary dysplasia (BPD). Glutathione (GSH) mediates susceptibility to neonatal and adult oxidative lung injury. We have previously shown that ATG attenuates hyperoxic lung injury and enhances glutathione- (GSH-) dependent antioxidant defenses in adult mice. Hypothesis: The present studies evaluated the effects of TXNRD1 inhibition on GSH-dependent antioxidant defenses in newborn mice in vivo and lung epithelia in vitro. Methods: Newborn mice received intraperitoneal ATG or saline prior to room air or 85% hyperoxia exposure. Glutamate-cysteine ligase (GCL) catalytic (Gclc) and modifier (Gclm) mRNA levels, total GSH levels, total GSH peroxidase (GPx) activity, and Gpx2 expression were determined in lung homogenates. In vitro, murine transformed club cells (mtCCs) were treated with the TXNRD1 inhibitor auranofin (AFN) or vehicle in the presence or absence of the GCL inhibitor buthionine sulfoximine (BSO). Results: In vivo, ATG enhanced hyperoxia-induced increases in Gclc mRNA levels, total GSH contents, and GPx activity. In vitro, AFN increased Gclm mRNA levels, intracellular and extracellular GSH levels, and GPx activity. BSO prevented AFN-induced increases in GSH levels. Conclusions: Our data are consistent with a model in which TXNRD1 inhibition augments hyperoxia-induced GSH-dependent antioxidant responses in neonatal mice. Discrepancies between in vivo and in vitro results highlight the need for methodologies that permit accurate assessments of the GSH system at the single-cell level.


Assuntos
Antioxidantes/metabolismo , Displasia Broncopulmonar/enzimologia , Displasia Broncopulmonar/patologia , Glutationa/metabolismo , Tiorredoxina Redutase 1/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Aurotioglucose , Displasia Broncopulmonar/genética , Células Epiteliais/metabolismo , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa Peroxidase/metabolismo , Hiperóxia/genética , Hiperóxia/patologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tiorredoxina Redutase 1/metabolismo
15.
Int J Mol Sci ; 20(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717178

RESUMO

Cadmium (Cd) is harmful for humans and animals, especially for the reproductive system. However, the mechanism of its toxicity has not been elucidated, and how to alleviate its toxicity is very important. This study aimed to explore the role and mechanism of action of sulforaphane (SFN) in protecting mouse Leydigs (TM3) cells from cadmium (Cd)-induced damage. The half-maximal inhibitory concentration (IC50) of Cd and the safe doses of SFN were determined using a methyl thiazolyl tetrazolium (MTT) assay. The testosterone secretion from TM3 cells was measured using the enzyme-linked immunosorbent assay. The intracellular oxidative stress was evaluated using corresponding kits. The cell apoptosis was detected using flow cytometry. The mRNA expression of genes associated with NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling was detected using reverse transcription⁻polymerase chain reaction, including Nrf2, heme oxygenase I (HO-1), glutathione peroxidase (GSH-Px), NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1), and γ-glutamylcysteine synthetase (γ-GCS). The protein expression of Nrf2, GSH-Px, HO-1, γ-GCS, and NQO1 was detected using Western blot analysis. The results showed that the IC50 of Cd to TM3 cells was 51.4 µmol/L. SFN reduced the release of lactate dehydrogenase from Cd-exposed cells. Cd + SFN 2.5 treatment significantly elevated testosterone concentration compared with the Cd group (p < 0.05). SFN significantly increased total superoxide dismutase (T-SOD) and GSH-Px activity and GSH content in Cd-treated cells (p < 0.05; p < 0.01), inhibited the production of malondialdehyde or reactive oxygen species caused by Cd (p < 0.05; p < 0.01), and reduced the apoptotic rate of Cd-induced TM3 cells (p < 0.01). SFN upregulated the mRNA expression of Nrf2, GSH-Px, HO-1, NQO1, and γ-GCS in Cd-treated cells, indicating the protective effect of SFN against Cd-induced oxidative stress or cell apoptosis by activating the Nrf2/ARE signaling pathway.


Assuntos
Antioxidantes/farmacologia , Cloreto de Cádmio/antagonistas & inibidores , Isotiocianatos/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Cloreto de Cádmio/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Testosterona/biossíntese
16.
Cancer Cell ; 35(2): 177-190.e8, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30686770

RESUMO

ARID1A encodes an SWI/SNF chromatin-remodeling factor and is frequently mutated in various cancers. This study demonstrates that ARID1A-deficient cancer cells are specifically vulnerable to inhibition of the antioxidant glutathione (GSH) and the glutamate-cysteine ligase synthetase catalytic subunit (GCLC), a rate-limiting enzyme for GSH synthesis. Inhibition of GCLC markedly decreased GSH in ARID1A-deficient cancer cells, leading to apoptotic cell death triggered by excessive amounts of reactive oxygen species. The vulnerability of ARID1A-deficient cancer cells results from low basal levels of GSH due to impaired expression of SLC7A11. The SLC7A11-encoded cystine transporter supplies cells with cysteine, a key source of GSH, and its expression is enhanced by ARID1A-mediated chromatin remodeling. Thus, ARID1A-deficient cancers are susceptible to synthetic lethal targeting of GCLC.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutamato-Cisteína Ligase/antagonistas & inibidores , Glutationa/metabolismo , Proteínas Nucleares/deficiência , Neoplasias Ovarianas/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Quinuclidinas/farmacologia , Fatores de Transcrição/deficiência , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Feminino , Glutamato-Cisteína Ligase/metabolismo , Células HCT116 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Proteínas Nucleares/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Nitric Oxide ; 84: 22-29, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30630055

RESUMO

Garlic has been demonstrated to exert protective effects against oxidative damage using numerous experimental models. The antioxidant effects of garlic are associated with the activation of Nrf2-dependent gene expression. S-1-Propenylcysteine (S1PC) and S-allylcysteine (SAC) are two predominant sulfur amino acids present in aged garlic extract; however, the exact roles of these amino acids within the Keap1/Nrf2 system remain unknown. We hypothesized that sulfur-containing amino acids derived from garlic could activate Nrf2 in the presence of nitric oxide (NO). Neither S1PC nor SAC affected gene expression of either heme oxygenase-1 (HMOX1) or the glutamate-cysteine ligase modifier subunit (GCLM) in human umbilical vein endothelial cells (HUVECs) or human aorta endothelial cells (HAECs). Interestingly, S1PC augmented expression levels induced by nitric oxide donors (NO-donors) such as NOR3 and GSNO. NO-donors were found to induce nuclear accumulation of NRF2 and activation of the eIF2α/ATF4 pathway, whereas S1PC did not further amplify the NO-induced effects on NRF2 or eIF2α/ATF4. Additionally, NO-donors induced the degradation of BTB domain and CNC homolog 1 (BACH1), a transcriptional repressor that can compete with NRF2. In addition, S1PC enhanced BACH1 downregulation within the nucleus. Pretreatment with deferoxamine, an inhibitor of heme synthesis, upregulated BACH1 protein levels and abolished the effect of NO-donors and S1PC on HMOX1 expression. The above results indicate that S1PC could modulate antioxidant gene expression via the NO/heme/BACH1 signaling pathway, thereby suggesting that S1PC-induced degradation of BACH1 may provide a basis for therapeutic applications.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Cisteína/análogos & derivados , Cisteína/farmacologia , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Óxido Nítrico/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Regulação para Baixo , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hidroxilaminas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
18.
Phytomedicine ; 52: 157-167, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30599895

RESUMO

BACKGROUND: Andrographis paniculata (A. paniculata), a traditional herb in Southeastern Asia, is used to treat inflammation-mediated diseases. PURPOSE: The two major bioactive diterpenoids in A. paniculata are andrographolide (AND) and 14-deoxy-11,12-didehydroandrographolide (deAND). Because of the anti-inflammatory evidence for AND, we hypothesized that deAND might possess similar potency for inhibiting monocyte adhesion to the vascular endothelium, which is a critical event for atherosclerotic lesion formation. MATERIAL: In the present study, we used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine cell viability. We evaluated the production of intracellular reactive oxygen species (ROS) by using DCFDA assay. We assayed the protein expression by using Western blot analysis, the mRNA expression by using RT-PCR, and the nuclear protein-DNA binding activity by using EMSA. RESULTS: We showed that pretreatment of EA.hy926 cells with A. paniculata ethanolic extract (APE), deAND, and AND significantly inhibited TNFα-induced ICAM-1 protein and mRNA expression, ICAM-1 promoter activity, and monocyte adhesion. TNFα-stimulated IKKß phosphorylation, IκBα phosphorylation and degradation, p65 nuclear translocation, and NFκB nuclear protein-DNA binding activity were attenuated by pretreatment with APE, deAND, and AND. APE, deAND, and AND attenuated TNFα-induced Src phosphorylation and membrane translocation of the NOX subunits p47phox and p67phox. Both APE and AND induced protein expression of heme oxygenase 1 and the glutamate cysteine ligase modifier subunit and enhanced glutathione content. Pretreatment with AND and deAND inhibited TNFα-induced ROS generation. CONCLUSION: These results suggest that the mechanism by which APE, deAND, and AND down-regulates TNFα-induced ICAM-1 expression in EA.hy926 cells is via attenuation of activation of the IKK/IκB/NFκB pathway.


Assuntos
Andrographis/química , Diterpenos/farmacologia , Molécula 1 de Adesão Intercelular/metabolismo , Extratos Vegetais/farmacologia , Linhagem Celular , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
19.
Plant Mol Biol ; 99(1-2): 149-159, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30617455

RESUMO

KEY MESSAGE: The WRKY transcription factor WRKY12 negatively regulates Cd tolerance in Arabidopsis via the glutathione-dependent phytochelatin synthesis pathway by directly targeting GSH1 and indirectly repressing phytochelatin synthesis-related gene expression. Cadmium (Cd) is a widespread pollutant toxic to plants. The glutathione (GSH)-dependent phytochelatin (PC) synthesis pathway plays key roles in Cd detoxification. However, its regulatory mechanism remains largely unknown. Here, we showed a previously unknown function of the WRKY transcription factor WRKY12 in the regulation of Cd tolerance by repressing the expression of PC synthesis-related genes. The expression of WRKY12 was inhibited by Cd stress. Enhanced Cd tolerance was observed in the WRKY12 loss-of-function mutants, whereas increased Cd sensitivity was found in the WRKY12-overexpressing plants. Overexpression and loss-of-function of WRKY12 were associated respectively with increased and decreased Cd accumulation by repressing or releasing the expression of the genes involved in the PC synthesis pathway. Transient expression assay showed that WRKY12 repressed the expression of GSH1, GSH2, PCS1, and PCS2. Further analysis indicated that WRKY12 could directly bind to the W-box of the promoter in GSH1 but not in GSH2, PCS1, and PCS2 in vivo. Together, our results suggest that WRKY12 directly targets GSH1 and indirectly represses PC synthesis-related gene expression to negatively regulate Cd accumulation and tolerance in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Cádmio/metabolismo , Regulação da Expressão Gênica de Plantas , Glutamato-Cisteína Ligase/metabolismo , Fitoquelatinas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutationa/metabolismo , Inativação Metabólica , Mutação com Perda de Função , Regiões Promotoras Genéticas/genética , Estresse Fisiológico , Fatores de Transcrição/genética
20.
Acta Pharmacol Sin ; 40(1): 75-85, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29921882

RESUMO

Toosendanin (TSN) is the main active compound in Toosendan Fructus and Meliae Cortex, two commonly used traditional Chinese medicines. TSN has been reported to induce hepatotoxicity, but its mechanism remains unclear. In this study, we demonstrated the critical role of nuclear factor erythroid 2-related factor 2 (Nrf2) in protecting against TSN-induced hepatotoxicity in mice and human normal liver L-02 cells. In mice, administration of TSN (10 mg/kg)-induced acute liver injury evidenced by increased serum alanine/aspartate aminotransferase (ALT/AST) and alkaline phosphatase (ALP) activities, and total bilirubin (TBiL) content as well as the histological changes. Furthermore, TSN markedly increased liver reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and decreased liver glutathione (GSH) content and Nrf2 expression. In L-02 cells, TSN (2 µM) time-dependently reduced glutamate-cysteine ligase (GCL) activity and cellular expression of the catalytic/modify subunit of GCL (GCLC/GCLM). Moreover, TSN reduced cellular GSH content and the increased ROS formation, and time-dependently decreased Nrf2 expression and increased the expression of the Nrf2 inhibitor protein kelch-like ECH-associated protein-1 (Keap1). Pre-administration of quercetin (40, 80 mg/kg) effectively inhibited TSN-induced liver oxidative injury and reversed the decreased expression of Nrf2 and GCLC/GCLM in vivo and in vitro. In addition, the quercetin-provided protection against TSN-induced hepatotoxicity was diminished in Nrf2 knock-out mice. In conclusion, TSN decreases cellular GSH content by reducing Nrf2-mediated GCLC/GCLM expression via decreasing Nrf2 expression. Quercetin attenuates TSN-induced hepatotoxicity by inducing the Nrf2/GCL/GSH antioxidant signaling pathway. This study implies that inducing Nrf2 activation may be an effective strategy to prevent TSN-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Medicamentos de Ervas Chinesas/efeitos adversos , Substâncias Protetoras/uso terapêutico , Quercetina/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , RNA Mensageiro/genética
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