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1.
Pestic Biochem Physiol ; 159: 118-126, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400773

RESUMO

In the plant-insect arms race, plants synthesize toxic compounds to defend against herbivorous insects, whereas insects employ cytochrome P450 monooxygenases (P450s) to detoxify these phytotoxins. As ubiquitous environmental contaminants, heavy metals can be easily absorbed by plants and further accumulated in herbivorous insects through the food chains, resulting in tangible consequences for plant-insect interactions. However, whether heavy metals can influence P450 activities and thereby cause further effects on larval tolerance to phytotoxins remains unknown. In this study, we shown that prior exposure to copper (Cu) enhanced larval tolerance to xanthotoxin in Spodoptera litura, a major polyphagous pest of agriculture. P450 activities were induced in larvae exposed to Cu or xanthotoxin, and a midgut specific expressed P450 gene, CYP6B50 was cross-induced after exposure to these two toxic xenobiotics. Knocking down CYP6B50 by RNA interference (RNAi) rendered the larvae more sensitive to xanthotoxin. As defense against oxidative stress following metal exposure has been demonstrated to affect insecticide resistance, the reactive oxygen species (ROS) generation and antioxidant enzyme activities were assessed. Cu exposure caused the accumulation of hydrogen peroxide (H2O2) and enhanced the activities of superoxide dismutase (SOD) and peroxidase (POD) in larval midgut. In addition, two antioxidant response elements (AREs) were identified from the CYP6B50 promoter, indicating that Cu-induced CYP6B50 expression may be related to the ROS burst. Application of ROS scavenger N-acetylcysteine (NAC) effectively suppressed CYP6B50 expression, inhibited P450 activities and impaired larval tolerance to xanthotoxin that had been induced by Cu. These results indicate that the increase in CYP6B50 expression regulated by Cu-induced H2O2 generation contributed to the enhancement of larval tolerance to xanthotoxin in S. litura. Ingestion of heavy metals from their host plants can inadvertently boost the counter-defense system of herbivorous insects to protect themselves against plant defensive toxins.


Assuntos
Cobre/farmacologia , Peróxido de Hidrogênio/metabolismo , Metoxaleno/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/metabolismo , Animais , Elementos de Resposta Antioxidante/genética , Elementos de Resposta Antioxidante/fisiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Interferência de RNA , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
2.
J Agric Food Chem ; 67(25): 7060-7072, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240928

RESUMO

As one of the main metabolites of anthocyanin, protocatechuic acid (PCA) possesses strong antioxidant activity. In the present study, we explored the capacity of PCA on the alleviation of endothelial oxidative stress and investigated the underlying mechanisms using RNA sequencing (RNA-Seq). In comparison with palmitic acid (PA)-treated cells, PCA (100 µM) significantly decreased the generations of 3-nitrotyrosine (3-NT) and 8-hydroxydeoxyguanosine (8-OHdG) (0.82 ± 0.01 vs 1.16 ± 0.05 and 0.80 ± 0.01 vs 1.48 ± 0.15, respectively, p < 0.01), two biomarkers of oxidative damage, and restored the levels of nitric oxide (NO) (0.97 ± 0.04 vs 0.54 ± 0.02, p < 0.01) and mitochondrial membrane potential (MMP) (0.96 ± 0.03 vs 0.86 ± 0.02, p < 0.01) in human umbilical vein endothelial cells (HUVECs). PCA also obviously reduced the level of reactive oxygen species (ROS) (0.86 ± 0.15 vs 2.67 ± 0.09, p < 0.01) in aorta from high-fat diet (HFD)-fed mice. RNA-Seq and Western blot analysis indicated that PCA markedly reduced the expression of cluster of differentiation 36 (CD36), a membrane fatty acid transporter, and reduced the generations of adenosine triphosphate (ATP) and acetyl coenzyme A (Ac-CoA). These effects of PCA were associated with decreased level of acetylated-lysine and restored the activity of manganese-dependent superoxide dismutase (MnSOD) through reducing the generation of Ac-CoA or activating Sirt1 and Sirt3 via a CD36/AMP-kinase (AMPK) dependent pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antígenos CD36/metabolismo , Hidroxibenzoatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/genética , Acetilação/efeitos dos fármacos , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Antígenos CD36/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
3.
Nat Commun ; 10(1): 2399, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160585

RESUMO

Manganese superoxide dismutase (MnSOD) functions as a tumor suppressor; however, once tumorigenesis occurs, clinical data suggest MnSOD levels correlate with more aggressive human tumors, implying a potential dual function of MnSOD in the regulation of metabolism. Here we show, using in vitro transformation and xenograft growth assays that the MnSOD-K68 acetylation (Ac) mimic mutant (MnSODK68Q) functions as a tumor promoter. Interestingly, in various breast cancer and primary cell types the expression of MnSODK68Q is accompanied with a change of MnSOD's stoichiometry from a known homotetramer complex to a monomeric form. Biochemical experiments using the MnSOD-K68Q Ac-mimic, or physically K68-Ac (MnSOD-K68-Ac), suggest that these monomers function as a peroxidase, distinct from the established MnSOD superoxide dismutase activity. MnSODK68Q expressing cells exhibit resistance to tamoxifen (Tam) and cells selected for Tam resistance exhibited increased K68-Ac and monomeric MnSOD. These results suggest a MnSOD-K68-Ac metabolic pathway for Tam resistance, carcinogenesis and tumor progression.


Assuntos
Neoplasias da Mama/genética , Carcinogênese/genética , Resistencia a Medicamentos Antineoplásicos/genética , Superóxido Dismutase/genética , Acetilação , Animais , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Técnicas In Vitro , Lisina/metabolismo , Células MCF-7 , Camundongos , Mutação , Transplante de Neoplasias , Peroxidase/metabolismo , Estrutura Quaternária de Proteína/genética , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tamoxifeno/uso terapêutico , Proteínas Supressoras de Tumor
4.
Gene ; 711: 143924, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31212050

RESUMO

The MnSOD Ala16Val single nucleotide polymorphism (SNP) has shown to be associated to inflammatory pathways and many metabolic disorders, such as obesity and dyslipidemia. Metabolic syndrome (MetS) is an emergent problem among patients with epilepsy. However, little is known about interaction between MnSOD Ala16Val SNP and metabolic comorbities in epilepsy. Thus, we investigated the relationship between MnSOD Ala16Val SNP with epilepsy and its influence on MetS, inflammation, apoptosis and DNA damage parameters. Ninety subjects were evaluated (47 epilepsy patients and 43 healthy controls) by questionnaires and laboratorial exams. Levels of inflammatory, apoptotic and DNA damage markers, as well as MnSOD polymorphism were assessed. An increased proportion of VV genotype in epilepsy group when compared to control group was observed. Tumor Necrosis Factor-α (TNF-α), Acetylcholinesterase, caspase-8, and Picogreen levels were increased in VV epilepsy group. An important correlation between TNF-α vs caspase-8, and Cholesterol vs. Triglycerides was observed in the epilepsy group with VV genotype. Our findings suggest that the MnSOD Ala16Val SNP might have an important role in epilepsy, mainly in patients with generalized seizures and particularly with VV genotype. The metabolic parameters also presented significant results in epilepsy group with VV genotype, which applying attention in view of further consequences and disorders that could be developed.


Assuntos
Substituição de Aminoácidos , Colesterol/metabolismo , Convulsões/genética , Superóxido Dismutase/genética , Triglicerídeos/metabolismo , Acetilcolinesterase/genética , Adulto , Estudos de Casos e Controles , Caspase 8/genética , Dano ao DNA , Feminino , Proteínas Ligadas por GPI/genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Estresse Oxidativo , Fator de Necrose Tumoral alfa/genética
5.
Food Chem ; 295: 129-137, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174741

RESUMO

Heat stress causes oxidative damage and quality reduction in poultry. Here, a tandem mass tag proteomic approach was applied to investigate the proteomic differences in duck meat from birds exposed to heat stress. Altogether 212 differential proteins were identified, including 178 down-regulated and 34 up-regulated proteins, compared to the control. Malondialdehyde and carbonyl content and cooking loss of the chest muscle significantly increased under heat stress. The proteomic analysis indicated that heat stress suppressed mitochondrial functions and respiratory chains, which might be responsible for the higher oxidation level. The results also revealed potential protective proteins involved in the defensive mechanisms against heat stress in duck muscles, such as sarcoplasmic/endoplasmic reticulum calcium ATPases, Mn-superoxide dismutase, heat shock protein family B member 7, methyltransferase like 21C, myosin-binding protein C, and carbonic anhydrase 3. These results provide potential targets for the research and identification of oxidative meat products due to heat stress.


Assuntos
Carne/análise , Estresse Oxidativo , Proteoma/análise , Proteômica/métodos , Animais , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/metabolismo , Culinária , Patos/metabolismo , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Masculino , Músculo Esquelético/metabolismo , Mapas de Interação de Proteínas , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
6.
J Sci Food Agric ; 99(13): 6097-6107, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31250448

RESUMO

BACKGROUND: Reactive oxygen species (ROS) can cause DNA damage. Rice protein (RP) inhibits ROS accumulation. However, a link between the reduction of ROS-derived DNA damage and the intake of RP is far from clear. The main objective of this study is to elucidate the effects of RPs on the reduction of DNA damage in growing and adult rats. RESULTS: An intake of RP for 2 weeks significantly reduced the hepatic accumulation of ROS and 8-hydroxydeoxyguanosine (8-OHdG) in growing and adult rats, whereas the hepatic p53 content was markedly increased by RPs. After 2 weeks' feeding, the mRNA levels and protein expressions of p53, ataxia-telangiectasia mutated (ATM), and Checkpoint kinase 2 (Chk2) were up-regulated by RPs, whereas Murine Double Minute 2 (MDM2) expressions were markedly inhibited by RPs, resulting in more p53 being translocated into the nucleus. Nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2) was activated by RP by reducing Kelch-like ECH-associated protein 1 (Keap1), resulting in the up-regulation of antioxidant expressions of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in RP groups. CONCLUSION: Rice protein can exert an endogenous antioxidant activity to reduce ROS-derived DNA damage by activating the Nrf2-Keap1 pathway. This study suggests that the activation of the ATM-Chk2-p53 pathway might be one of the mechanisms exerted by RP for reducing DNA damage in growing and adult rats. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Dano ao DNA , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Catalase/genética , Catalase/metabolismo , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53/genética
7.
Ecotoxicol Environ Saf ; 181: 428-434, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220783

RESUMO

The evidence is increasing that prenatal air pollutant exposure contributes to elevated oxidative stress in children, but the underlying mechanism is unclear. A pilot study was conducted in China to explore the associations between prenatal ambient air pollution exposure and superoxide dismutase 2 (SOD2) promoter methylation in maternal and cord blood. After detection and analyses, SOD2 promoter methylation levels in umbilical cord blood were elevated as maternal SOD2 promoter methylation levels increased. In addition, the SOD2 promoter methylation levels in umbilical cord blood were positively associated with the particulate matter 10 (PM10) exposure concentrations during the entire pregnancy and the second trimester. In maternal peripheral blood, the SOD2 promoter methylation levels were positively associated with the exposure concentrations of PM10 (during the entire pregnancy and the second trimester) and nitrogen dioxide (NO2) (during the first trimester of pregnancy), whereas the levels were negatively associated with the exposure concentrations of NO2 during the third trimester of pregnancy. Additionally, interaction analyses revealed that the maternal SOD2 promoter methylation level and sulfur dioxide (SO2) exposure (during the entire pregnancy and the third trimester), as well as NO2 exposure (during the third trimester of pregnancy), had an interaction effect on the SOD2 promoter methylation level in umbilical cord blood. Furthermore, mediation analysis revealed that the associations between SOD2 promoter methylation in umbilical cord blood and PM10 exposure during the entire pregnancy and the second trimester were partly mediated by maternal SOD2 promoter methylation. In conclusion, prenatal exposure to air pollutants was significantly associated with SOD2 promoter methylation levels in umbilical cord blood, and this association may be affected by SOD2 promoter methylation levels in maternal peripheral blood. These associations may be one of the mechanisms by which prenatal air pollutant exposure leads to oxidative stress in newborns.


Assuntos
Poluição do Ar/análise , Metilação de DNA , Sangue Fetal/química , Exposição Materna , Superóxido Dismutase/genética , Poluentes Atmosféricos/sangue , China , Feminino , Humanos , Recém-Nascido , Masculino , Projetos Piloto , Gravidez , Regiões Promotoras Genéticas , Fatores de Risco , Superóxido Dismutase/sangue
8.
BMC Complement Altern Med ; 19(1): 144, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226981

RESUMO

BACKGROUND: Moringa oleifera, also known as horseradish tree or drumstick tree, has strong antioxidant properties. In the present study, we investigated the potential effect of Moringa oleifera stem extract (MOSE) on cataract formation induced by oxidative stress in cultured mouse lenses. METHODS: Mouse lenses cultured in vitro were pretreated with MOSE (0.5 and 1 mg/mL) for 24 h. Then, 1 mM hydrogen peroxide was added, and mouse lenses were cultured for a further 24 h. The medium was then changed to normal culture medium. After 48 h, lens opacification, reactive oxygen species (ROS) generation, reduced glutathione (GSH) content, and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in lens tissues. In addition, the protein expression of peroxisome proliferator-activated receptor alpha (PPARα), a nuclear receptor with potential benefits to improve vision-threatening eye diseases, was assayed. RESULTS: MOSE (1 mg/mL) alleviated lens opacification, reduced ROS generation, increased GSH content, and elevated SOD and CAT activities in cultured lenses. Moreover, MOSE upregulated the expressions of SOD, CAT, and PPARα. CONCLUSIONS: This study showed that MOSE alleviates oxidative stress-induced cataract formation, and the mechanism of the effect is mainly related to its improvement of the endogenous antioxidant system in the lens.


Assuntos
Catarata/tratamento farmacológico , Cristalino/efeitos dos fármacos , Moringa oleifera/química , Extratos Vegetais/administração & dosagem , Animais , Catalase/genética , Catalase/metabolismo , Catarata/induzido quimicamente , Glutationa/genética , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/efeitos adversos , Cristalino/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/genética , PPAR alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
9.
Mol Med Rep ; 19(6): 5386-5396, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059059

RESUMO

Stress is a pivotal factor for inflammation, reactive oxygen species (ROS) production and formation of visceral hypersensitivity (VH) in the process of gastroesophageal reflux disease (GERD). In the present study, the effects of stress on esophageal inflammation, oxidative stress and VH were investigated in a chronic restraint stress mouse model. C57BL/6J male mice were subjected to 2 weeks of intermittent restraint stress, and histopathological analysis revealed that stress induced esophageal inflammation and fibrosis, while no distinct changes were detected in non­stressed control mice. In addition, increased NADPH oxidase 4 expression was observed in the plasma and esophagus of stressed mice, indicating accumulation of ROS. The expression levels of antioxidants, including Mn­superoxide dismutase (MnSOD), Cu/Zn­SOD, catalase and glutathione peroxidase, were also analyzed using reverse transcription­quantitative polymerase chain reaction (RT­qPCR). In addition, transient receptor potential vanilloid 1 (TRPV­1) and protease­activated receptor 2 (PAR­2), which are crucial receptors for VH, were measured by immunohistochemistry and RT­qPCR. The results demonstrated that stress markedly reduced antioxidant expression, while it significantly upregulated TRPV­1 and PAR­2 expression levels in the mouse esophagus. Finally, 2 weeks of restraint stress significantly increased the esophageal and plasma levels of inflammatory cytokines, including interleukin (IL)­6, IL­8, interferon­Î³ and tumor necrosis factor­α. Taken together, the present study results indicated that stress­induced esophageal inflammation and ROS generation involves VH.


Assuntos
Esôfago/patologia , Inflamação , Receptor PAR-2/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Catalase/genética , Catalase/metabolismo , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Esôfago/citologia , Esôfago/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor PAR-2/genética , Estresse Fisiológico , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/genética , Regulação para Cima
10.
Clin Biochem ; 69: 15-20, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129183

RESUMO

OBJECTIVE: Despite the current guidelines for the management of type 2 diabetes mellitus (T2DM), patients still struggle with the hyperglycemia consequences. Imbalance in zinc homeostasis, in particular, renders diabetic patients more susceptible to the damages of oxidative stress. This study aimed to evaluate the effects of zinc supplementation on the superoxide dismutase gene expression and enzyme activity in overweight individuals with T2DM. Additionally, biochemical parameters, such as fasting blood glucose (FBG), insulin, glycated hemoglobin (HbA1c), homeostasis model of assessment-insulin resistance (HOMA-IR), serum levels of zinc and lipid profile, were assessed. METHODS: In this randomized, double-blind, placebo-controlled trial, 70 overweight (BMI > 25) T2DM patients were selected based on the inclusion criteria. They were divided into two groups for supplementation of daily 50 mg zinc gluconate or placebo for 8 weeks. Blood samples were collected from all the individuals in the zinc group and controls for analysis. RESULTS: The results showed that, in comparison with the control group, zinc supplementation increased both gene expression and enzyme activity of SOD (p < 0.01) as well as the levels of insulin (p = 0.02) among the patients in the zinc group. Moreover, there was a meaningful reduction in the levels of FBG, HbA1c and HOMA-IR value (p < 0.001), triglycerides and total cholesterol (p < 0.05) after the zinc treatment. CONCLUSIONS: Taken together, the current study suggests that daily supplementation with 50 mg zinc gluconate could be a useful approach for the management of overweight T2DM. CLINICAL TRIAL REGISTRATION: IRCT2015083102.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Sobrepeso/complicações , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Zinco/administração & dosagem , Adulto , Idoso , Biomarcadores/sangue , Glicemia/análise , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/genética , Método Duplo-Cego , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Placebos , RNA Mensageiro/metabolismo
11.
Int J Mol Sci ; 20(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091755

RESUMO

In this study, we generated transgenic durum wheat cv. Maali overexpressing the wheat plasma membrane aquaporin TdPIP2;1 gene under the control of PrTdPIP2;1 promoter or under the constitutive PrCaMV35S promoter. Histochemical analysis of the fusion PrTdPIP2;1::TdPIP2;1::GusA in wheat plants showed that the ß-glucuronidase (GUS) activity was detected in the leaves, stems and roots of stably transformed wheat T3 plants. Our results showed that transgenic wheat lines overexpressing the TdPIP2;1 gene exhibited improved germination rates and biomass production and retained low Na+ and high K+ concentrations in their shoots under high salt and osmotic stress conditions. In a long-term study under greenhouse conditions on salt or drought stress, transgenic TdPIP2;1 lines produced filled grains, whereas wild-type (WT) plants either died at the vegetative stage under salt stress or showed drastically reduced grain filling under drought stress. Performing real time RT-PCR experiments on wheat plants transformed with the fusion PrTdPIP2;1::GusA, we showed an increase in the accumulation of GusA transcripts in the roots of plants challenged with salt and drought stress. Study of the antioxidant defence system in transgenic wheat TdPIP2;1 lines showed that these lines induced the antioxidative enzymes Catalase (CAT) and Superoxide dismutase (SOD) activities more efficiently than the WT plants, which is associated with lower malondialdehyde and hydrogen peroxide contents. Taken together, these results indicate the high potential of the TdPIP2;1 gene for reducing water evaporation from leaves (water loss) in response to water deficit through the lowering of transpiration per unit leaf area (stomatal conductance) and engineering effective drought and salt tolerance in transgenic TdPIP2;1 lines.


Assuntos
Aquaporinas/genética , Secas , Proteínas de Plantas/genética , Tolerância ao Sal , Triticum/genética , Aquaporinas/metabolismo , Catalase/genética , Catalase/metabolismo , Germinação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Triticum/metabolismo , Triticum/fisiologia , Regulação para Cima
12.
Curr Microbiol ; 76(7): 835-841, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31053905

RESUMO

A novel facultative anaerobic and Gram-stain-positive coccus, designated strain ChDC F135T, was isolated from human subgingival dental plaque of periodontitis lesion and was characterized by polyphasic taxonomic analysis. The 16S rRNA gene (16S rDNA) sequence of strain ChDC F135T was closest to that of Streptococcus sinensis HKU4T (98.2%), followed by Streptococcus intermedia SK54T (97.0%), Streptococcus constellatus NCTC11325T (96.0%), and Streptococcus anginosus NCTC 10713T (95.7%). In contrast, phylogenetic analysis based on the superoxide dismutase gene (sodA) and the RNA polymerase beta-subunit gene (rpoB) showed that the nucleotide sequence similarities of strain ChDC F135T were highly similar to the corresponding genes of S. anginosus NCTC 10713T (99.2% and 97.6%, respectively), S. constellatus NCTC11325T (87.8% and 91.4%, respectively), and S. intermedia SK54T (85.8% and 91.2%, respectively) rather than those of S. sinensis HKU4T (80.5% and 82.6%). The complete genome of strain ChDC F135T consisted of 1,901,251 bp and the G+C content was 38.9 mol %. Average nucleotide identity value between strain ChDC F135T and S. sinensis HKU4T or S. anginosus NCTC 10713T were 75.7% and 95.6%, respectively. The C14:0 composition of the cellular fatty acids of strain ChDC F135T (32.8%) was different from that of S. intermedia (6-8%), S. constellatus (6-13%), and S. anginosus (13-20%). Based on the results of phylogenetic and phenotypic analysis, strain ChDC F135T (= KCOM 2412T = JCM 33300T) was classified as a type strain of a novel species of the genus Streptococcus, for which we proposed the name Streptococcus periodonticum sp. nov.


Assuntos
Placa Dentária/microbiologia , Periodontite/microbiologia , Streptococcus/classificação , Streptococcus/fisiologia , Bactérias Anaeróbias , Proteínas de Bactérias/genética , Composição de Bases , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Ácidos Graxos/análise , Genoma Bacteriano/genética , Humanos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Streptococcus/genética , Superóxido Dismutase/genética
13.
Int J Mol Sci ; 20(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072025

RESUMO

Abscisic acid (ABA)-, stress-, and ripening-induced (ASR) proteins are reported to be involved in drought stress responses. However, the function of maize ASR genes in enhancing drought tolerance is not known. Here, nine maize ASR members were cloned, and the molecular features of these genes were analyzed. Phenotype results of overexpression of maize ZmASR3 gene in Arabidopsis showed lower malondialdehyde (MDA) levels and higher relative water content (RWC) and proline content than the wild type under drought conditions, demonstrating that ZmASR3 can improve drought tolerance. Further experiments showed that ZmASR3-overexpressing transgenic lines displayed increased stomatal closure and reduced reactive oxygen species (ROS) accumulation by increasing the enzyme activities of superoxide dismutase (SOD) and catalase (CAT) under drought conditions. Moreover, overexpression of ZmASR3 in Arabidopsis increased ABA content and reduced sensitivity to exogenous ABA in both the germination and post-germination stages. In addition, the ROS-related, stress-responsive, and ABA-dependent pathway genes were activated in transgenic lines under drought stress. Taken together, these results suggest that ZmASR3 acts as a positive regulator of drought tolerance in plants.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Secas , Fatores Genéricos de Transcrição/genética , Zea mays/genética , Ácido Abscísico/genética , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Catalase/genética , Regulação da Expressão Gênica de Plantas , Malondialdeído/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Zea mays/metabolismo
14.
Pestic Biochem Physiol ; 156: 72-79, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027583

RESUMO

Metalloenzyme SODs play important roles in insects dealing with environmental stress. Here, we cloned the Cu/ZnSOD (LdCZS) and MnSOD (LdMS) mRNA of Lymantria dispar by rapid amplification of cDNA ends (RACE). Afterwards their expression patterns were detected by quantitative real-time polymerase chain reaction (qPCR) after bioinformatic analysis. We found that both LdCZS and LdMS were widely detected in all gypsy moth larvae and all five tissues that we analyzed, and both of them were up-regulated after larvae were fed with avermectin of sublethal concentration and LC10. The LdCZS expression value are always higher than LdMS after treating with avermectin of sublethal concentrations. In addition, temporal expression profile in avermectin treated larvae showed that LdCZS expressed highest at 2nd hour, and LdMS expressed highest at 6th hour. The cuticulas transcribed LdCZS and LdMS significantly higher than heads, fat bodies, Malpighian tubes, and midguts after spraying avermectin of sublethal concentration. These results suggested that both Cu/ZnSOD and MnSOD are important antioxidant enzymes in L. dispar defensing against pesticide stress, and LdCZS always responded rapider and stronger than LdMS.


Assuntos
Ivermectina/análogos & derivados , Larva/metabolismo , Mariposas/metabolismo , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Animais , Biologia Computacional , DNA Complementar/genética , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Larva/genética , Dados de Sequência Molecular , Mariposas/efeitos dos fármacos , Mariposas/genética , Praguicidas/farmacologia , Reação em Cadeia da Polimerase , Superóxido Dismutase/química , Superóxido Dismutase/genética
15.
Ecotoxicol Environ Saf ; 176: 279-287, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30947031

RESUMO

2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) and 2,2',4,4',5-pentabromodiphenyl ether (BDE-99) are two typical polybrominated diphenyl ethers (PBDEs), and studies have proven that these PBDs can disrupt the behaviors and physical function of aquatic organisms. However, little is known about the compositional impacts of BDE-47/BDE-99 compound pollution on the feeding behavior of Daphnia magna. In this study, a response surface methodology (RSM) was introduced into the combined toxicity assessment of BDE-47 and BDE-99 on the feeding depression of D. magna. Low concentrations of BDE-47 (9.2 µg/L) and BDE-99 (5.4 µg/L) had no effect on the feeding behavior of D. magna; nevertheless, the feeding depression was strengthened, and a concentration-dependent effect was observed with increasing concentrations of BDE-47 and BDE-99. The results of RSM indicated that the mixture of BDE-47 and BDE-99 can enhance their toxicity on the feeding behavior of D. magna. Moreover, real-time PCR (qPCR) analysis showed that the down-regulation of α-amylase (AMS) appeared in most of the exposed D. magna. However, there were significant different in the gene expression of trypsin, superoxide dismutase (SOD) and catalase (CAT) between the exposure and control groups. The change in the enzyme activity of AMS, trypsin, SOD and CAT implied that BDE-47 and BDE-99 cause damage to the digestive and antioxidative systems of D. magna. Correlation analysis indicated that a significant positive correlation existed between the gene expression and enzyme activity of SOD and CAT. Our results contribute to the understanding of toxicity caused by BDE-47/BDE-99 compound pollution in D. magna and help to improve traditional toxicity assessment methods for aquatic environments.


Assuntos
Antioxidantes/metabolismo , Daphnia/efeitos dos fármacos , Digestão/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Éteres Difenil Halogenados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/genética , Daphnia/enzimologia , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Superóxido Dismutase/genética
16.
Fish Shellfish Immunol ; 89: 354-360, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30959182

RESUMO

Vibrio alginolyticus is an opportunistic and halophilic Gram-negative pathogen in limiting the development of aquatic industry and affecting human health. SODs are oxidative enzymes that play a critical role in oxidative defense. In this study, an in-frame deleted mutant strain (ΔsodB) was constructed by allelic exchange mutagenesis to investigate physiological role of sodB in pathogenicity of V. alginolyticus. The results exhibited that ΔsodB showed no differences in growth compared with wild-type strain HY9901 (WT), but led to increasing in biofilm formation, ECPase activity and sensitivity to hydrogen peroxide, decreasing in swarming motility, adherence to CIK cells, SOD activity and virulence. In addition, ΔsodB induced a high antibody titer and provided a valid protection with a relative percent survival value of 86.5% without inducing clinical symptoms after challenging with WT. These results suggest that sodB is important for normal physiological function, oxidation resistance and virulence in V. alginolyticus, and ΔsodB may be considered as an effective live attenuated vaccine against V. alginolyticus.


Assuntos
Proteínas de Bactérias/genética , Vacinas Bacterianas/imunologia , Bass/imunologia , Doenças dos Peixes/prevenção & controle , Superóxido Dismutase/genética , Vibrio alginolyticus/imunologia , Vibrio alginolyticus/fisiologia , Fatores de Virulência/genética , Animais , Antioxidantes/metabolismo , Proteínas de Bactérias/metabolismo , Doenças dos Peixes/imunologia , Mutagênese , Estresse Fisiológico , Superóxido Dismutase/metabolismo , Vacinas Atenuadas/imunologia , Vibrioses/imunologia , Vibrioses/prevenção & controle , Vibrioses/veterinária , Vibrio alginolyticus/genética , Virulência , Fatores de Virulência/metabolismo
17.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959759

RESUMO

Guava (Psidium guajava L., Myrtaceae) leaves have been used as a folk herbal tea to treat diabetes for a long time in Asia and North America. In this study, we isolated polysaccharides from guava leaves (GLP), and evaluated its antioxidant activity in vitro and anti-diabetic effects on diabetic mice induced by streptozotocin combined with high-fat diet. The results indicated that GLP exhibited good DPPH, OH, and ABTS free-radical scavenging abilities, and significantly lowered fasting blood sugar, total cholesterol, total triglycerides, glycated serum protein, creatinine, and malonaldehyde. Meanwhile, it significantly increased the total antioxidant activity and superoxide dismutase (SOD) enzyme activity in diabetic mice, as well as ameliorated the damage of liver, kidney, and pancreas. Thus, polysaccharides from guava leaves could be explored as a potential antioxidant or anti-diabetic agents for functional foods or complementary medicine.


Assuntos
Antioxidantes/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Polissacarídeos/administração & dosagem , Psidium/química , Animais , Antioxidantes/química , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica/efeitos adversos , Depuradores de Radicais Livres/administração & dosagem , Depuradores de Radicais Livres/química , Humanos , Insulina/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Pâncreas/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Superóxido Dismutase/genética
18.
MBio ; 10(2)2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940703

RESUMO

Mercury (Hg) is a widely distributed, toxic heavy metal with no known cellular role. Mercury toxicity has been linked to the production of reactive oxygen species (ROS), but Hg does not directly perform redox chemistry with oxygen. How exposure to the ionic form, Hg(II), generates ROS is unknown. Exposure of Thermus thermophilus to Hg(II) triggered ROS accumulation and increased transcription and activity of superoxide dismutase (Sod) and pseudocatalase (Pcat); however, Hg(II) inactivated Sod and Pcat. Strains lacking Sod or Pcat had increased oxidized bacillithiol (BSH) levels and were more sensitive to Hg(II) than the wild type. The ΔbshA Δsod and ΔbshA Δpcat double mutant strains were as sensitive to Hg(II) as the ΔbshA strain that lacks bacillithiol, suggesting that the increased sensitivity to Hg(II) in the Δsod and Δpcat mutant strains is due to a decrease of reduced BSH. Treatment of T. thermophilus with Hg(II) decreased aconitase activity and increased the intracellular concentration of free Fe, and these phenotypes were exacerbated in Δsod and Δpcat mutant strains. Treatment with Hg(II) also increased DNA damage. We conclude that sequestration of the redox buffering thiol BSH by Hg(II), in conjunction with direct inactivation of ROS-scavenging enzymes, impairs the ability of T. thermophilus to effectively metabolize ROS generated as a normal consequence of growth in aerobic environments.IMPORTANCE Thermus thermophilus is a deep-branching thermophilic aerobe. It is a member of the Deinococcus-Thermus phylum that, together with the Aquificae, constitute the earliest branching aerobic bacterial lineages; therefore, this organism serves as a model for early diverged bacteria (R. K. Hartmann, J. Wolters, B. Kröger, S. Schultze, et al., Syst Appl Microbiol 11:243-249, 1989, https://doi.org/10.1016/S0723-2020(89)80020-7) whose natural heated habitat may contain mercury of geological origins (G. G. Geesey, T. Barkay, and S. King, Sci Total Environ 569-570:321-331, 2016, https://doi.org/10.1016/j.scitotenv.2016.06.080). T. thermophilus likely arose shortly after the oxidation of the biosphere 2.4 billion years ago. Studying T. thermophilus physiology provides clues about the origin and evolution of mechanisms for mercury and oxidative stress responses, the latter being critical for the survival and function of all extant aerobes.


Assuntos
Catalase/metabolismo , Cisteína/análogos & derivados , Tolerância a Medicamentos , Glucosamina/análogos & derivados , Compostos de Mercúrio/toxicidade , Superóxido Dismutase/metabolismo , Thermus thermophilus/efeitos dos fármacos , Thermus thermophilus/enzimologia , Catalase/genética , Cisteína/metabolismo , Deleção de Genes , Glucosamina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Thermus thermophilus/genética , Thermus thermophilus/metabolismo
19.
Nat Commun ; 10(1): 1914, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015473

RESUMO

Degradation of extracellular matrix (ECM) underlies loss of cartilage tissue in osteoarthritis, a common disease for which no effective disease-modifying therapy currently exists. Here we describe BNTA, a small molecule with ECM modulatory properties. BNTA promotes generation of ECM components in cultured chondrocytes isolated from individuals with osteoarthritis. In human osteoarthritic cartilage explants, BNTA treatment stimulates expression of ECM components while suppressing inflammatory mediators. Intra-articular injection of BNTA delays the disease progression in a trauma-induced rat model of osteoarthritis. Furthermore, we identify superoxide dismutase 3 (SOD3) as a mediator of BNTA activity. BNTA induces SOD3 expression and superoxide anion elimination in osteoarthritic chondrocyte culture, and ectopic SOD3 expression recapitulates the effect of BNTA on ECM biosynthesis. These observations identify SOD3 as a relevant drug target, and BNTA as a potential therapeutic agent in osteoarthritis.


Assuntos
Anti-Inflamatórios/farmacologia , Benzamidas/farmacologia , Cartilagem Articular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Fatores Imunológicos/farmacologia , Osteoartrite/tratamento farmacológico , Sulfonamidas/farmacologia , Animais , Cartilagem Articular/imunologia , Cartilagem Articular/patologia , Condrócitos/efeitos dos fármacos , Condrócitos/imunologia , Condrócitos/patologia , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Progressão da Doença , Matriz Extracelular/imunologia , Matriz Extracelular/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Injeções Intra-Articulares , Masculino , Osteoartrite/genética , Osteoartrite/imunologia , Osteoartrite/patologia , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/genética , Superóxido Dismutase/imunologia , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo , Transcriptoma/imunologia
20.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974814

RESUMO

Manganese-dependent superoxide dismutase (MnSOD, SodA) and iron-dependent SOD (FeSOD, SodB) are critical cytosolic enzymes for alleviating superoxide stress. Distinct from the singular sodA gene in most bacteria, Stenotrophomonas maltophilia harbors two sodA genes, sodA1 and sodA2. The roles of SodA1, SodA2, and SodB of S. maltophilia in alleviating superoxide stress were investigated. The expression of sod genes was determined by promoter-xylE transcriptional fusion assay and qRT-PCR. SodA2 and sodB expressions were proportional to the bacterial logarithmic growth, but unaffected by menadione (MD), iron, or manganese challenges. SodA1 was intrinsically unexpressed and inducibly expressed by MD. Complementary expression of sodA1 was observed when sodA2 was inactivated. The individual or combined sod deletion mutants were constructed using the gene replacement strategy. The functions of SODs were assessed by evaluating cell viabilities of different sod mutants in MD, low iron-stressed, and/or low manganese-stressed conditions. Inactivation of SodA1 or SodA2 alone did not affect bacterial viability; however, simultaneously inactivating sodA1 and sodA2 significantly compromised bacterial viability in both aerobic growth and stressed conditions. SodA1 can either rescue or support SodA2 when SodA2 is defective or insufficiently potent. The presence of two MnSODs gives S. maltophilia an advantage against superoxide stress.


Assuntos
Proteínas de Bactérias/metabolismo , Estresse Oxidativo , Stenotrophomonas maltophilia/enzimologia , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Proteínas de Bactérias/genética , Stenotrophomonas maltophilia/genética , Superóxido Dismutase/genética
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