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1.
Ecotoxicol Environ Saf ; 190: 110119, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31891835

RESUMO

Chlorothalonil is an effective fungicide used in agriculture and formulations of antifouling paints, which use and possible toxicity has been generating great concern. Thus, the present study investigated the effects of chlorothalonil on the antioxidant defense system (ADS) of the mussel Perna perna. The ADS was evaluated in gills and digestive gland after 24 h and 96 h of exposure to environmental relevant levels of chlorothalonil (0.1 and 10 µg/L). The activity of the enzymes superoxide dismutase (SOD), catalase (CAT), glutamate cysteine-ligase (GCL) and glutathione S-transferase (GST), levels of non-enzymatic defenses, represented by glutathione (GSH), and lipoperoxidation (LPO) and protein carbonyls (PCO) were evaluated. Results indicated that exposure to chlorothalonil is affecting the ADS in both tissues. While the activity of SOD increased and GST and GSH were not altered in gills, they decreased in digestive gland after 24 h of exposure to 10 µg/L of chlorothalonil. The contrasting results indicate that gills and digestive gland presented different patterns of responses after exposure to chlorothalonil. Moreover, a tissue-specific response to chlorothalonil was observed. Gills could be acting as the first line of defense, presenting higher enzymatic levels with minor effects on the parameters analyzed. On the other hand, digestive gland, with lower levels of antioxidant defenses, was the most affect organ by chlorothalonil. It also should be highlighted that the fungicide reduced the glutathione metabolism in the digestive gland, which can lead to an imbalance of the redox state within the cells of animals.


Assuntos
Antioxidantes/metabolismo , Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Perna (Organismo)/fisiologia , Animais , Catalase/metabolismo , Fungicidas Industriais/metabolismo , Brânquias/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Perna (Organismo)/efeitos dos fármacos , Superóxido Dismutase/metabolismo
2.
Chem Biol Interact ; 315: 108876, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669340

RESUMO

4-methylesculetin (4 ME) is a natural antioxidant coumarin with protective effects on the intestinal inflammation, in which oxidative stress plays a key role in its aetiology and pathophysiology. Based on this, we examined the antioxidant molecular mechanisms involved in the intestinal anti-inflammatory activity of the 4 ME. For this purpose, we investigated the effects of the 4 ME on the modulation of gene expression and antioxidant-related enzyme activities in TNBS model of intestinal inflammation as well as the molecular interaction between 4 ME and glutathione reductase. Our results showed that 4 ME modulated glutathione-related enzymes, mainly increasing glutathione reductase activity. These effects were related to upregulation of glutathione reductase and Nrf2 gene expression. Fluorescence and nuclear magnetic resonance data showed that interaction between 4 ME and glutathione reductase is collisional, hydrophobic and spontaneous, in which C4 methyl group is the second epitope most buried into glutathione reductase. Molecular modelling calculation showed Lys70-B, Arg81-A, Glu381-B, Asp443-A, Ser444-A, Glu447-B and Ser475-A participated in electrostatic interaction, Lys70-B, Glu381-B and Arg81-A acted in the hydrophobic interactions and Trp73, Phe377 and Ala446 are responsible for the hydrogen bonds. Based on this, our results showed 4 ME acted by different mechanisms to control oxidative stress induced by intestinal damage, controlling the imbalance between myeloperoxidase activity and glutathione production, upregulating the glutathione S-transferase and glutathione reductase activities, preventing the Nrf2 and glutathione gene expression downregulation with consequent glutathione maintenance. Finally, 4 ME interacted at molecular level with glutathione reductase, stabilizing its enzymatic activity and reducing oxidative stress to take place in intestinal inflammatory process.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cumarínicos/farmacologia , Inflamação/tratamento farmacológico , Umbeliferonas/farmacologia , Animais , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Inflamação/metabolismo , Masculino , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Ratos , Ratos Wistar
3.
Exp Parasitol ; 209: 107810, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31801691

RESUMO

Fasciolosis is a neglected tropical disease caused by the liver fluke Fasciola gigantica. The absence of successful vaccine and emerging resistance in flukes against the drug of choice, triclabendazole, has necessitated the search for alternatives including phyto-therapeutic approaches. Curcumin and thymoquinone, the active ingredients of Curcuma longa and Nigella sativa plants respectively, were first screened for their binding affinity with Glutathione-S-transferase (GST) molecule through in silico molecular docking followed by in vitro treatment of worms with varying concentrations of the test compounds. The in silico molecular docking of curcumin and thymoquinone with sigma GST revealed strong hydrogen bonding as well as hydrophobic interactions with high fitness scores but showing inter-specific differences. The in vitro treatment of F. gigantica worms with both curcumin and thymoquinone resulted in a significant increase in the generation of reactive oxygen species (ROS) whereas the level of reduced glutathione, a primary redox regulator, was found to be significantly decreased (p < 0.05). The two compounds not only inhibited the GST activity, which is an important detoxification enzyme and also a key drug/vaccine target for the control of fasciolosis but also significantly inhibited the activity of antioxidant enzymes glutathione peroxidase and glutathione reductase that are vital in maintenance of redox homeostasis. The immunohistochemistry performed using anti sigma GST polyclonal antibodies revealed that both the compounds used in the present study significantly reduced immunofluorescence in the vitellaria, developing eggs present in the ovary and the intestinal caecae indicating inhibition of GST enzyme in these regions of the worms. Further, following treatment with curcumin and thymoquinone, chromatin condensation and DNA fragmentation was also observed in F. gigantica worms. In conclusion, both curcumin and thymoquinone generated oxidative stress in the worms by production of ROS and significantly inhibiting their antioxidant and detoxification ability. The oxidative stress along with induction of apoptotic like events would compromise the survival ability of worms within the host. However, further studies are required to establish their anthelmintic potential alone and in combination with the commonly used anthelmintic drugs under in vivo conditions.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Curcumina/farmacologia , Fasciola/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Benzoquinonas/química , Búfalos , Cromatina/efeitos dos fármacos , Curcumina/química , Dano ao DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Eletroforese em Gel de Ágar , Inibidores Enzimáticos/farmacologia , Fasciola/citologia , Fasciola/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/antagonistas & inibidores , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Imuno-Histoquímica , Microscopia Confocal , Modelos Moleculares , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio/metabolismo
4.
Food Chem ; 308: 125663, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655474

RESUMO

Apple exocarp was used to investigate the effect of acibenzolar-S-methyl (ASM) and dehydroepiandrosterone (DHEA) treatments on reaction oxygen species (ROS) metabolism. The results indicated that ASM enhanced the hydrogen peroxide (H2O2) content, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH). ASM also increased the contents of ascorbic acid (AsA), reduced glutathione (GSH) and nicotinamide ademine dinucleotidephosphate (NADPH), MdSOD and MdAPX expression, but decreased MdMDHAR and dehydroascorbate reductase (MdDHAR) expression. DHEA suppressed H2O2 accumulation and POD, APX, MDHAR, G6PDH activities, but increased SOD, CAT and GR activities compared to the control. ASM and DHEA treatments suppressed the contents of AsA, GSH and NADPH, and expression of MdSOD, MdAPX and MdMDHAR. These results suggest that DHEA treatment prevented ROS metabolism induced by ASM which showed the important role of G6PDH in maintaining redox homeostasis in apple exocarp.


Assuntos
Glucosefosfato Desidrogenase/metabolismo , Malus/enzimologia , Espécies Reativas de Oxigênio/metabolismo , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , NADH NADPH Oxirredutases/metabolismo , Oxirredução , Oxirredutases/metabolismo , Superóxido Dismutase/metabolismo , Tiadiazóis/metabolismo
5.
Ecotoxicol Environ Saf ; 190: 110054, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864121

RESUMO

Heavy metal exposure induces oxidative stress in terrestrial organisms, which they counteract via activation of antioxidant biomarkers. The present study investigated the effects of copper (Cu) and lead (Pb) on the total antioxidant capacity (TAC) and antioxidant enzymes such as Catalase (CAT), Glutathione reductase (GR), Superoxide dismutase (SOD) and Glutathione peroxidase (GPX) in two spider species, namely Lycosa terrestris and Pardosa birmanica. The spiders were exposed to Cu and Pb separately (10 ppm) or in combination (10 ppm each) via two different exposure routes (i.e. food and soil) for 10, 20 and 40 days. The results showed that metal accumulation and antioxidant biomarker responses in spiders were metal- and species-dependent. Also, the levels of all antioxidant biomarkers increased significantly with increasing exposure time and metal load in the bodies of spiders via both exposure routes. The significant inhibition of TAC and antioxidant enzyme activities was only observed in single Pb treatment through soil exposure. In L. terrestris, the activities of detoxification enzymes and TAC were significantly enhanced on single Cu exposure than Pb via both exposure routes. However, in P. birmanica consistent variation among antioxidant parameters were observed depending on the metal load and exposure routes. The combined metal exposure caused more pronounced increase in the level of antioxidants compared to single metal exposure in both species, mainly via food exposure. These results suggest that the antioxidant enzymes and TAC are sensitive to single and combined metal exposure via both uptake routes. These data show that antioxidant parameters can be used potential biomarkers of oxidative stress associated with metal exposure and for monitoring environmental health using spiders as bioindicators.


Assuntos
Cobre/toxicidade , Biomarcadores Ambientais , Poluentes Ambientais/toxicidade , Chumbo/toxicidade , Aranhas/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Cobre/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Chumbo/análise , Estresse Oxidativo , Aranhas/química , Aranhas/enzimologia , Aranhas/metabolismo , Superóxido Dismutase/metabolismo
6.
Chemosphere ; 239: 124523, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499308

RESUMO

Arsenic (As) is a toxic metalloid that severely hampers plant growth and also poses health risks for humans through the food chain. Although nitric oxide (NO) is known to improve plant resistance to multiple stresses including metal toxicity, little is known about its role in the As tolerance of hyperaccumulator plants. This study investigates the role of the exogenously applied NO donor, sodium nitroprusside (SNP), in improving the As tolerance of Isatis cappadocica, which has been reported to hyperaccumulate As. Exposure to toxic As concentrations significantly increases NO production and damages the cell membrane, as indicated by increased hydrogen peroxide (H2O2) and malondialdehyde (MDA) concentrations, thereby reducing plant growth. However, the addition of SNP improves growth and alleviates As-induced oxidative stress by enhancing the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione S-transferase (GST), glutathione (GSH), as well as proline and thiol concentrations, thereby confirming the beneficial role played by NO in increasing As stress tolerance. Furthermore, the As-induced decrease in growth and the increase in oxidative stress were more marked in the presence of bovine hemoglobin (Hb; a NO scavenger) and N(G)-nitro-l-arginine methyl ester (l-NAME; a NO synthase inhibitor), thus demonstrating the protective role of NO against As toxicity. The reduction in NO concentrations by l-NAME suggests that NOS-like activity is involved in the generation of NO in response to As in I. cappadocica.


Assuntos
Antioxidantes/metabolismo , Arsênico/toxicidade , Isatis/efeitos dos fármacos , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Animais , Ascorbato Peroxidases/metabolismo , Bovinos , Membrana Celular/patologia , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , Isatis/metabolismo , Malondialdeído/metabolismo , Doadores de Óxido Nítrico , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
7.
World J Microbiol Biotechnol ; 35(11): 170, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673816

RESUMO

Debaryomyces hansenii is a halotolerant yeast of importance in basic and applied research. Previous reports hinted about possible links between saline and oxidative stress responses in this yeast. The aim of this work was to study that hypothesis at different molecular levels, investigating after oxidative and saline stress: (i) transcription of seven genes related to oxidative and/or saline responses, (ii) activity of two main anti-oxidative enzymes, (iii) existence of common metabolic intermediates, and (iv) generation of damages to biomolecules as lipids and proteins. Our results showed how expression of genes related to oxidative stress was induced by exposure to NaCl and KCl, and, vice versa, transcription of some genes related to osmotic/salt stress responses was regulated by H2O2. Moreover, and contrary to S. cerevisiae, in D. hansenii HOG1 and MSN2 genes were modulated by stress at their transcriptional level. At the enzymatic level, saline stress also induced antioxidative enzymatic defenses as catalase and glutathione reductase. Furthermore, we demonstrated that both stresses are connected by the generation of intracellular ROS, and that hydrogen peroxide can affect the accumulation of in-cell sodium. On the other hand, no significant alterations in lipid oxidation or total glutathione content were observed upon exposure to both stresses tested. The results described in this work could help to understand the responses to both stressors, and to improve the biotechnological potential of D. hansenni.


Assuntos
Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Estresse Oxidativo/fisiologia , Saccharomycetales/fisiologia , Estresse Salino/fisiologia , Antioxidantes , Catalase/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/genética , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio , Metabolismo dos Lipídeos , Osmorregulação/genética , Osmorregulação/fisiologia , Estresse Oxidativo/genética , Cloreto de Potássio/metabolismo , Proteômica , Saccharomycetales/genética , Estresse Salino/genética , Sódio/metabolismo , Cloreto de Sódio/metabolismo , Fatores de Transcrição/genética
8.
Ecotoxicol Environ Saf ; 186: 109747, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31634660

RESUMO

Cadmium (Cd) contamination has generated an environmental problem worldwide, leading to harmful effects on human health and damages to plant metabolism. Selenium (Se) is non essential for plants, however it can improve plant growth and reduce the adverse effects of abiotic stress. In addition, ethylene may interplay the positive effects of Se in plants. In order to investigate the role of ethylene in Se-modulation of antioxidant defence system in response to Cd-stress, we tested the hormonal mutant Epinastic (epi) with a subset of constitutive activation of the ethylene response and Micro-Tom (MT) plants. For this purpose, Se mineral uptake, Cd and Se concentrations, pigments, malondialdeyde (MDA) and hydrogen peroxide (H2O2) contents, ethylene production, glutathione (GSH) compound, and superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GSH-Px) activities were analysed in MT and epi plants submitted to 0.5 mM CdCl2 and 1 µM of selenate or selenite. MT plants treated with both Se forms increased growth in the presence or not of 0.5 mM CdCl2, but not change epi growth. Both Se forms reduced Cd uptake in MT plants and cause reverse effect in epi plants. P, Mg, S, K and Zn uptake increased in epi plants with Se application, irrespective to Cd exposure. Chlorophylls and carotenoids contents decreased in both genotypes under Cd exposure, in contrast to what was observed in epi leaves in the presence of Se. When antioxidant enzymes activities were concerned, Se application increased Mn-SOD, Fe-SOD and APX activities. In the presence of Cd, MT and epi plants exhibited decreased SOD activity and increased CAT, APX and GR activities. MT and epi plants with Se supply exhibited increased APX and GR activities in the presence of Cd. Overall, these results suggest that ethylene may be involved in Se induced-defence responses, that triggers a positive response of the antioxidant system and improve growth under Cd stress. These results showed integrative roles of ethylene and Se in regulating the cell responses to stressful-conditions and, the cross-tolerance to stress could be used to manipulate ethylene regulated gene expression to induce heavy metal tolerance.


Assuntos
Antioxidantes/metabolismo , Cádmio/efeitos adversos , Etilenos/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Adaptação Fisiológica , Ascorbato Peroxidases/metabolismo , Cádmio/metabolismo , Catalase/metabolismo , Exposição Ambiental , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Lycopersicon esculentum/metabolismo , Mutação , Oxirredução , Folhas de Planta/metabolismo , Ácido Selênico/farmacologia , Ácido Selenioso/farmacologia , Selênio/metabolismo , Superóxido Dismutase/metabolismo
9.
Plant Physiol Biochem ; 144: 178-186, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31574383

RESUMO

The present investigation describes aluminum-induced changes in the leaves of two buckwheat species using both physiological and biochemical indices. With increasing levels of Al (viz. 100, 200 and 300 µM), the mean length of root, shoot as well as their biomass accumulation decreased linearly with respect to control. Tolerance test of F. kashmirianum revealed that it was more tolerant to Al-stress than F. tataricum as revealed by higher accumulation of Al in its roots without any significant damage. Translocation factor (TF) values of both species were found to be < 1, indicating more Al is restrained in roots. Total chlorophyll showed a non-significant increase in F. tataricum while as decreased in F. kashmirianum at 300 µM concentration besides, the carotenoid content exhibited inclined trend in F. tataricum and showed a concomitant decrease in F. kashmirianum. The anthocyanin level showed a non-significant decline in F. kashmirianum. Exposure to different Al-treatments enhances malondialdehyde (MDA), H2O2 and membrane stability index (MSI) in both species, with increases being greater in F. kashmirianum than F. tataricum as also revealed by DAB-mediated in vivo histo-chemical detection method. The osmolyte level in general were elevated in both buckwheat species however, enhancement was more in F. tataricum than F. kashmirianum. The activities of antioxidant enzymes viz. superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (POD), glutathione reductase (GR), glutathione-S-transferase (GST) were positively correlated with Al-treatment except catalase (CAT) which exhibits a reverse outcome in F. kashmirianum. The present investigation could play an essential role to better understand the detoxification mechanisms of Al in plants.


Assuntos
Alumínio/toxicidade , Fagopyrum/metabolismo , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Peroxidase/metabolismo
10.
Food Chem Toxicol ; 134: 110835, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31562949

RESUMO

Carvacrol is a monoterpenic phenol found in essential oils, is considered a safe food additive, and possesses various therapeutic properties. Numerous studies have also deciphered the protective role of carvacrol on various cytotoxicities. We clarify the effects of carvacrol on cadmium-induced apoptosis in PC12 cells. Carvacrol while co-exposed with cadmium for 48 h raised PC12 cell viability in comparison to only cadmium exposed group. The co-exposure increased the cellular glutathione levels and promoted the expression of glutathione reductase. The magnitude of DNA fragmentation caused by cadmium was also ameliorated by carvacrol. Flow cytometry exhibited the apoptosis rate augmented by cadmium was reduced by carvacrol. Western blotting revealed that cadmium and carvacrol co-exposure alleviated the cadmium-induced down-regulations of mammalian target of rapamycin (mTOR), protein kinase B (Akt), nuclear factor kappa-light-chain-enhancer of activated B cells (NFКB), extracellular signal-regulated kinase-1 (ERK-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) expressions. The co-exposure also reversed action of cadmium by suppressing the cleavage of caspase 3 and reducing the cytosolic levels of cytochrome c and apoptosis inducing factor (AIF). Moreover, carvacrol upon co-exposure significantly increased the intracellular metallothionein content. In conclusion, carvacrol strongly reduced cadmium-triggered oxidative stress and caspase-dependent and caspase-independent apoptosis in PC12 cells.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Caspase 3/metabolismo , /farmacologia , Animais , Fator de Indução de Apoptose/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Dano ao DNA , Glutationa/metabolismo , Glutationa Redutase/metabolismo , L-Lactato Desidrogenase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos
11.
Comput Biol Chem ; 83: 107121, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546211

RESUMO

Antioxidant enzymes (AEs) are the main parts of the natural barriers of the body which deactivate the oxidant factors. To discover and understand their structures and function will deserve a deeper investigation. Accordingly, as an AE of probiotic strains, glutathione reductase of Streptococcus thermophilus (GRst), is characterized and modeled by in-silico methods. The investigation indicated the physicochemical properties of the enzyme and estimated its half-life of being more than 10 h. The analysis revealed that the enzyme is composed of 86 strands, 123 helices, and 241 random coils. Homology modeling of the GRst led to the construction of the enzyme's 3D model that 62% of which is analogous to the glutathione reductase of Escherichia Coli (GRec), and which is qualitatively high in terms of Molpdf, ERRAT, Verify-3D and Ramachandran scores. Moreover, the structural stability of the model was substantiated within 10 and 20 ns at 400 and 300 K, respectively. Interestingly, these data showed that the enzyme is more stable than GRec at 400 K. In other words, the active cavity of the constructed model is characteristic of 38 amino acid residues within 4 Šaround the NADPH and GSSG as corresponding ligands of GRst. Noteworthy, herein is the fact that, CYS40 and CYS45 are specified as the active site residues of this enzyme. Furthermore, the interaction assays of the model support its antioxidant capability which is even more than that of GRec. In general, these data provide a new model of AEs being inclusive of high antioxidant capacity and thermostability.


Assuntos
Simulação por Computador , Glutationa Redutase/química , Glutationa Redutase/metabolismo , Simulação de Dinâmica Molecular , Streptococcus thermophilus/enzimologia , Estabilidade Enzimática
12.
Plant Physiol Biochem ; 143: 72-82, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31491702

RESUMO

Little information is available on the physiological and biochemical responses to water stress in eggplant (Solanum melongena). We evaluated four genetically diverse eggplant varieties (MEL3-MEL6) under control and water stress conditions. Measurements were taken for plant growth, tissue water content, levels of chlorophylls a and b, carotenoids, proline, malondialdehyde, total phenolics, total flavonoids, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities. For most traits, the water stress treatment had a greater contribution than the variety effect to the total sums of squares in an ANOVA analysis, except for total flavonoids, SOD, APX, and GR. The water stress treatment had a strong effect on plant growth and tissue water content. In general, water stress reduced the three photosynthetic pigments, increased proline, malondialdehyde, total phenolics, and total flavonoids, although some varietal differences were observed. Different patterns were also detected in the activities of the four enzymes evaluated, but few differences were observed for individual varieties between the control and water stress treatments. Many significant phenotypic correlations were observed among the traits studied, but only eight environmental correlations were detected. A PCA analysis distinctly separated individuals according to the treatment, and revealed a clearer separation of varieties under water stress than under control conditions, pointing to varietal differences in the responses to stress. Our results suggest that proline could be used as a marker for drought stress tolerance in this species. The information obtained provides new insight on the physiological and biochemical responses of eggplant to drought stress.


Assuntos
Solanum melongena/metabolismo , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Secas , Glutationa Redutase/metabolismo , Peroxidação de Lipídeos/fisiologia , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Fotossíntese/fisiologia , Prolina/metabolismo , Superóxido Dismutase/metabolismo
13.
Int J Nanomedicine ; 14: 4991-5015, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371943

RESUMO

Purpose: This study evaluates the cytotoxicity of AuNPs coated with polyallylamine (AuNPs-PAA) and conjugated or not to the epidermal growth factor receptor (EGFR)-targeting antibody Cetuximab (AuNPs-PAA-Ctxb) in normal human kidney (HK-2), liver (THLE-2) and microvascular endothelial (TIME) cells, and compares it with two cancer cell lines that are EGFR-overexpressing (A431) or EGFR-negative (MDA-MB-453). Results: Conjugation of Cetuximab to AuNPs-PAA increased the AuNPs-PAA-Ctxb interactions with cells, but reduced their cytotoxicity. TIME cells exhibited the strongest reduction in viability after exposure to AuNPs-PAA(±Ctxb), followed by THLE-2, MDA-MB-453, HK-2 and A431 cells. This cell type-dependent sensitivity was strongly correlated to the inhibition of thioredoxin reductase (TrxR) and glutathione reductase (GR), and to the depolarization of the mitochondrial membrane potential. Both are suggested to initiate apoptosis, which was indeed detected in a concentration- and time-dependent manner. The role of oxidative stress in AuNPs-PAA(±Ctxb)-induced cytotoxicity was demonstrated by co-incubation of the cells with N-acetyl L-cysteine (NAC), which significantly decreased apoptosis and mitochondrial membrane depolarization. Conclusion: This study helps to identify the cells and tissues that could be sensitive to AuNPs and deepens the understanding of the risks associated with the use of AuNPs in vivo.


Assuntos
Antioxidantes/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetuximab/farmacologia , Endocitose/efeitos dos fármacos , Glutationa Redutase/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tamanho da Partícula , Poliaminas/química , Substâncias Protetoras/farmacologia , Eletricidade Estática , Tiorredoxina Dissulfeto Redutase/metabolismo
14.
Food Chem ; 301: 125303, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387045

RESUMO

The effects of exogenous polyamines treatment on reactive oxygen species (ROS) metabolism in apricot fruits were systematically analyzed through the investigation of their curative and preventive effects on black spot disease. Results showed that 1.5 mM spermine (Spm), 1.5 mM spermidine (Spd) and 10 mM putrescine (Put) treatment significantly inhibited black spot development, additionally, the efficacy of this control was dependent upon the type of polyamines used and concentration level applied. Further studies have shown that exogenous polyamines treatments significantly improved production of O2- and H2O2, and increased the activities and gene expression levels of NADPH oxidase (NOX), super oxide dismutase (SOD), catalase (CAT) ascorbate peroxidase (AXP) and glutathione reductase (GR) in apricot fruit. Increased ascorbic acid (AsA) and reduced glutathione (GSH) content were also observed after exogenous polyamines treatment. These results have revealed that postharvest polyamines treatment effectively enhanced disease resistance through the maintenance of homeostasis in apricot fruits.


Assuntos
Alternaria/patogenicidade , Frutas/efeitos dos fármacos , Doenças das Plantas/microbiologia , Poliaminas/farmacologia , Prunus armeniaca/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Resistência à Doença/efeitos dos fármacos , Frutas/metabolismo , Frutas/microbiologia , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Homeostase/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Oxirredução , Prunus armeniaca/metabolismo , Prunus armeniaca/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
15.
Food Funct ; 10(9): 5531-5543, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31418439

RESUMO

Caenorhabditis elegans is an important model organism for studying stress response mechanisms and identifying genetic pathways that influence longevity. The present study was designed to explore the in vivo-antioxidant potential and the probable mechanism of acid hydrolysates prepared from A. auricula polysaccharides (AAPHs-F) with the optimal acid hydrolysis conditions using Box-Behnken design, and C. elegans was used as a model organism. The effects of AAPHs-F on the locomotory behavior, lifespan, activities of antioxidant-related enzymes and levels of antioxidants in C. elegans were studied. In addition, the potential of AAPHs-F in up-regulating the expression of antioxidant-related genes in C. elegans, such as daf-16, skn-1, sod-1, sod-2 and sir-2.1, and the inhibition of cell apoptosis of C. elegans were also discussed. The results indicated that AAPHs-F could significantly increase the U-Turn frequency of nematodes, extend their lifespan, enhance antioxidant systems including superoxide dismutase (SOD) by 70.60%, catalase (CAT) by 73.45% and glutathione reductase (GR) by 258.68% (p < 0.01), increase the level of glutathione (GSH) by 110.22% (p < 0.01), and decrease the level of reactive oxygen species (ROS) and malondialdehyde (MDA) by 31.86% and 46.16% (p < 0.01), respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that AAPHs-F could up-regulate mRNA expression levels of daf-16, skn-1, sir, sod-1 and sod-2 in wild-type C. elegans (>1.3 fold) when treated at a concentration of 0.1 mg mL-1 (p < 0.05 or p < 0.01). AAPHs-F was concluded to be heteropolysaccharides composed of mannose, glucose and galactose with a molar ratio of 12.7 : 3.25 : 1. The molecular weight of AAPHs-F was determined to be 885.37 Da. Furthermore, AAPHs-F is mainly formed of (1 → 3)-linked-α-d-glucopyranose, and carboxyl or acetamide is present in the molecule. In summary, our studies provide evidence that AAPHs-F helps improve the antioxidant defense system, and up-regulation of stress and longevity related genes suggests the possible involvement of these genes in the prevention of stress damage in C. elegans.


Assuntos
Antioxidantes/farmacologia , Basidiomycota/química , Caenorhabditis elegans/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Antioxidantes/química , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Catalase/genética , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Hidrólise , Longevidade/efeitos dos fármacos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Polissacarídeos/química , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
16.
Biomarkers ; 24(7): 666-676, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31368361

RESUMO

Synergy occurs when chemicals give pronounced effect on combination in contrast to their individual effect. The objective of this study was to investigate the synergistic effect of pesticides carbaryl (C) and methyl parathion (MP) on oxidative stress biomarkers viz catalase (CAT), glutathione reductase (GSSG-R) including different enzymes like lactate dehydrogenase (LDH), succinate dehydrogenase (SDH) and acetyl cholinesterase (AChE) in different tissues of carps Catla catla. Fishes were exposed to 6.25 mg/L of MP and 2.3 mg/L of C in mixture (one-third of LC50 value). CAT and GSSG-R were studied in gills, brain, liver and muscle of carp were found to be elevated significantly (p < 0.005). LDH activity increased significantly (p < 0.005) in synergistic group, there was a seven-fold (748%) increase in LDH activity in muscle compared to individual studies with same pesticides. Contrary to LDH, sudden decrease in SDH activity was accounted. Significant (p < 0.005) decrease in AChE activity after initial 24 h was remarkable addressing to the shift in neurotransmission pathway in organism. Significant increase was observed in activity of CAT and GSSG-R in all tissues compared to control fishes in individual as well as synergistic (MP + C) group suggesting that CAT and GSSG-R can be a potential biomarker of oxidative stress when studied in combination.


Assuntos
Catalase/metabolismo , Glutationa Redutase/metabolismo , Praguicidas/toxicidade , Animais , Biomarcadores/metabolismo , Carbaril/toxicidade , Carpas , Sinergismo Farmacológico , Peixes , Metil Paration/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Distribuição Tecidual
17.
J Agric Food Chem ; 67(37): 10448-10457, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31453693

RESUMO

Carabrone is isolated from Carpesium macrocephalum Franch. et Sav, which has good fungicidal activity, especially for Gaeumannomyces graminis (Get). According to previous studies, we speculated that carabrone targets the mitochondrial enzyme complex III of Get. To elucidate the mode of action, we used carabrone to induce oxidative stress and apoptosis in Get. Incubation with carabrone reduced the burst of reactive oxygen species (ROS) and mitochondrial membrane potential, as well as phosphatidylserine release. Carabrone caused ROS accumulation in mycelia by inhibiting the activity of antioxidase enzymes, among which inhibition of glutathione reductase (GR) activity was most obvious. The catalytic center of GR consists of l-cysteine residues that react with the α-methylene-γ-butyrolactone active site of carabrone. Additionally, a positive TUNEL reaction led to diffusion of the DNA electrophoresis band and upregulation of Ggmet1 and Ggmet2. We propose that carabrone inhibits antioxidant enzymes and promotes ROS overproduction, which causes membrane hyperpermeability, release of apoptotic factors, activation of the mitochondria-mediated apoptosis pathway, and fungal cell apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Ascomicetos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ascomicetos/citologia , Ascomicetos/metabolismo , Asteraceae/química , Proteínas Fúngicas/metabolismo , Glutationa Redutase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Oxid Med Cell Longev ; 2019: 2164698, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428221

RESUMO

Objective: The main aim of the study was an assessment of the influence of rapid weight loss on oxidative stress parameters in judokas differing in weight reduction value. Materials and Methods: The study included 30 judokas with an age range of 18-30 years (mean age: 22.4 ± 3.40 years). Enzymatic and nonenzymatic antioxidative markers, lipid peroxidation markers, and total oxidative stress were assessed three times: one week before a competition (the first stage), after gaining the desired weight (the second stage), and one week after the competition (the third stage). Results: Between the first and the second stage, the concentration of lipid hydroperoxides (LPH) decreased significantly. The superoxide dismutase (SOD), copper- and zinc-containing superoxide dismutase (Cu,Zn-SOD), ceruloplasmin (CER), malondialdehyde (MDA), LPH, and total oxidative stress (TOS) concentrations were the lowest one week after the competition. Linear regression indicated that the emphases on increased weight reduction increased the activity of glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), and protein sulfhydryl (PSH) between the first and the second stage of the study. Moderate weight reduction (2-5%) resulted in elevated levels of SOD, Mn-SOD, LPH, MDA, and TOS in comparison to low and high reductions. An opposite relation was observed in PSH. In judokas, the precompetitional weight reduction range was 0.44-6.10% (mean: 2.93% ± 1.76%) of the initial body weight. Concentrations of superoxide dismutase (SOD; p < .01), manganese-dependent superoxide dismutase (Mn-SOD; p < .001), and ceruloplasmin (CER; p < .05) decreased between the first and the third stage of the study as well between the second and third one. Before competitions, a decrease in lipid hydroperoxide (LPH; p < .01) concentration was observed. A reduction of malondialdehyde (MDA; p < .05), LPH (p < .01), and total oxidative stress (TOS; p < .05) levels between the first and the final stage occurred. The increase in weight reduction was linearly correlated with the rise of glutathione peroxidase (GPx; p < .05), glutathione reductase (GR; p < .05), glutathione S-transferase (GST; p < .05), and protein sulfhydryl (PSH; p < .05) concentrations between the first and the second stage of the study. Moderate weight reduction (2-5%) resulted in elevated levels of SOD (p < .05), Mn-SOD (p < .05), LPH (p < .05), MDA (p < .05), and TOS (p < .05) in comparison to low and high reductions. An opposite relation was observed in PSH (p < .005). Conclusions: The effect of weight reduction in judo athletes on prooxidative-antioxidative system diversity depends on the weight reduction value.


Assuntos
Antioxidantes/metabolismo , Estresse Oxidativo , Perda de Peso , Adolescente , Adulto , Ceruloplasmina/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo , Adulto Jovem
19.
Nat Commun ; 10(1): 3896, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467270

RESUMO

Iron (Fe) is essential for life, but in excess can cause oxidative cytotoxicity through the generation of Fe-catalyzed reactive oxygen species. It is yet unknown which genes and mechanisms can provide Fe-toxicity tolerance. Here, we identify S-nitrosoglutathione-reductase (GSNOR) variants underlying a major quantitative locus for root tolerance to Fe-toxicity in Arabidopsis using genome-wide association studies and allelic complementation. These variants act largely through transcript level regulation. We further show that the elevated nitric oxide is essential for Fe-dependent redox toxicity. GSNOR maintains root meristem activity and prevents cell death via inhibiting Fe-dependent nitrosative and oxidative cytotoxicity. GSNOR is also required for root tolerance to Fe-toxicity throughout higher plants such as legumes and monocots, which exposes an opportunity to address crop production under high-Fe conditions using natural GSNOR variants. Overall, this study shows that genetic or chemical modulation of the nitric oxide pathway can broadly modify Fe-toxicity tolerance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Arabidopsis/metabolismo , Tolerância a Medicamentos/fisiologia , Glutationa Redutase/metabolismo , Ferro/metabolismo , Ferro/toxicidade , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Morte Celular , Loci Gênicos , Estudo de Associação Genômica Ampla , Glutationa Redutase/genética , Haplótipos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/toxicidade , Meristema/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico/toxicidade , Nitrosação , Estresse Oxidativo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas
20.
Chemistry ; 25(55): 12810-12819, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31298434

RESUMO

The Hg-C bond of MeHgCl, a ubiquitous environmental toxicant, is notoriously inert and exceedingly difficult to cleave. The cleavage of the Hg-C bond of MeHgCl at low temperature, therefore, is of significant importance for human health. Among various bis(imidazole)-2-selones Ln Se (n=1-4, or 6), the three-spacer L3 Se shows extraordinarily high reactivity in the degradation of various mercury alkyls including MeHgCl because of its unique ability to coordinate through κ2 -fashion, in which both the Se atoms simultaneously attack the Hg center of mercury alkyls for facile Hg-C bond cleavage. It has the highest softness (σ) parameter and the lowest HOMO(Ln Se)-LUMO(MeHgX) energy gap and, thus, L3 Se is the most reactive among Ln Se towards MeHgX (X=Cl or I). L3 Se is highly efficient, more than L1 Se, in restoring the activity of antioxidant enzyme glutathione reductase (GR) that is completely inhibited by MeHgCl; 80 % GR activity is recovered by L3 Se relative to 50 % by L1 Se. It shows an excellent cytoprotective effect in liver cells against MeHgCl-induced oxidative stress by protecting vital antioxidant enzymes from inhibition caused by MeHgCl and, thus, does not allow to increase the intracellular reactive oxygen species (ROS) levels. Furthermore, it protects the mitochondrial membrane potential (ΔΨm ) from perturbation by MeHgCl. Major Hg-responsive genes analyses demonstrate that L3 Se plays a significant role in MeHg+ detoxification in liver cells.


Assuntos
Antioxidantes/farmacologia , Glutationa Redutase/metabolismo , Substâncias Perigosas/análise , Mercúrio/análise , Mercúrio/toxicidade , Compostos Organometálicos/química , Espécies Reativas de Oxigênio/metabolismo , Selênio/química , Antioxidantes/química , Citoproteção , Glutationa Redutase/química , Substâncias Perigosas/química , Humanos , Mercúrio/química , Espécies Reativas de Oxigênio/química , Selênio/análise
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