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1.
Environ Pollut ; 257: 113632, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31785942

RESUMO

Syringic acid, which is a typical methoxyphenol emitted from wood combustion, can provide heterogeneous reaction sites for gaseous active components, influencing the concentrations of trace gases and the compositions of syringic acid. The heterogeneous uptake of O3 on syringic acid was investigated using a flow tube reactor under ambient pressure. The initial uptake coefficient (γi) and the steady-state uptake coefficient (γss) of O3 linearly increased with syringic acid mass (0-0.16 µg cm-2) and temperature (278-328 K), while they decreased with increasing the O3 concentration and the O2 content. The γi was independent of relative humidity (20%-70%), whereas γss decreased with relative humidity (7%-70%). The compositional changes of syringic acid by the ozonization were analyzed by the Fourier transform infrared spectrometer (FT-IR) and the gas chromatography-mass spectrometry (GC-MS), confirming the generation of 2,6-dimethoxy-1,4-benzoquinone. In addition, compared to that of fresh syringic acid, the mass absorption efficiency of syringic acid aged by O3 exhibited an increase in the range of 290-320 nm.


Assuntos
Ácido Gálico/análogos & derivados , Ozônio , Ácido Gálico/química , Umidade , Ozônio/química , Ozônio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
2.
Ann Anat ; 227: 151428, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31610254

RESUMO

Aging is a normal process associated with neurodegenerative changes resulting in decline of cognitive and motor functions. Oxidative stress plays an important role. Controlled ozone (O3) therapy has been proved to induce oxidative preconditioning thus reversing oxidative stress. To the best of our knowledge, this research is the first attempt to investigate whether the antioxidant properties of O3 can ameliorate age-associated structural alterations of the cerebral cortex. Ozone administration (at a dose of 0.7mg/kg intraperitonially, three times a week for eight weeks) produced significant downregulation of tissue malondialdehyde (MDA) and upregulation of glutathione, superoxide dismutase (SOD) and catalase (CAT) within the frontal cortex of aged rats. Sections of the frontal cortex from adult and aged rats were stained with hematoxylin and eosin and analyzed using light microscopy. In addition, quantitative immunohistochemical assessments of the expression of inducible nitric oxide synthase (iNOS), caspase-3, glial fibrillary acidic protein (GFAP), Ki67 and acetylcholinesterase (AChE) were performed. Our results revealed the beneficial effect of O3 in improving the neurodegenerative changes of the cerebral cortex of aged rats. Moreover, this study clarified that O3 exerted its effects via reducing oxidative stress, apoptosis, gliosis as well as improving neurogenesis and cholinergic plasticity. This work added to the previously proved aging - associated neurodegenerative effects and provided a new insight into the promising role of O3 to ameliorate these effects.


Assuntos
Envelhecimento/patologia , Lobo Frontal/patologia , Ozônio/uso terapêutico , Animais , Caspase 3/metabolismo , Catalase/análise , Regulação para Baixo , Lobo Frontal/química , Lobo Frontal/enzimologia , Proteína Glial Fibrilar Ácida/metabolismo , Glutationa/análise , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Malondialdeído/análise , Óxido Nítrico Sintase Tipo II/metabolismo , Ozônio/metabolismo , Ratos , Superóxido Dismutase/análise , Regulação para Cima
3.
Plant Biol (Stuttg) ; 22 Suppl 1: 5-11, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30734441

RESUMO

Human activities result in a wide array of pollutants being released to the atmosphere. A number of these pollutants have direct effects on plants, including carbon dioxide (CO2 ), which is the substrate for photosynthesis, and ozone (O3 ), a damaging oxidant. How plants respond to changes in these atmospheric air pollutants, both directly and indirectly, feeds back on atmospheric composition and climate, global net primary productivity and ecosystem service provisioning. Here we discuss the past, current and future trends in emissions of CO2 and O3 and synthesise the current atmospheric CO2 and O3 budgets, describing the important role of vegetation in determining the atmospheric burden of those pollutants. While increased atmospheric CO2 concentration over the past 150 years has been accompanied by greater CO2 assimilation and storage in terrestrial ecosystems, there is evidence that rising temperatures and increased drought stress may limit the ability of future terrestrial ecosystems to buffer against atmospheric emissions. Long-term Free Air CO2 or O3 Enrichment (FACE) experiments provide critical experimentation about the effects of future CO2 and O3 on ecosystems, and highlight the important interactive effects of temperature, nutrients and water supply in determining ecosystem responses to air pollution. Long-term experimentation in both natural and cropping systems is needed to provide critical empirical data for modelling the effects of air pollutants on plant productivity in the decades to come.


Assuntos
Poluição do Ar , Dióxido de Carbono , Ozônio , Fenômenos Fisiológicos Vegetais , Dióxido de Carbono/metabolismo , Ecossistema , Ozônio/metabolismo , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos
5.
Biofactors ; 45(4): 536-547, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31087730

RESUMO

The effects of environmental insults on human health are a major global concern. Some of the most noxious pollutants that humans are exposed to include ozone (O3 ), particulate matter (PM), and cigarette smoke (CS). Since the skin is the first line of defense against environmental insults, it is considered one of the main target organs for the harmful insults of air pollution. Thus, there is solid evidence that skin pathologies such as premature aging, atopic dermatitis (AD), and psoriasis are associated with pollutant exposure; all of these skin conditions are also associated with an altered redox status. Therefore, although the mechanisms of action and concentrations of O3 , PM, and CS that we are exposed to differ, exposure to all of these pollutants is associated with the development of similar skin conditions due to the fact that all of these pollutants alter redox homeostasis, increasing reactive oxygen species production and oxidative stress. A main product of oxidative stress, induced by exposure to the aforementioned pollutants, is 4-hydroxy-2-nonenal (HNE), which derives from the oxidation of ω-6 polyunsaturated fatty acids. HNE is a highly reactive compound that can form adducts with cellular proteins and even DNA; it is also an efficient cell signaling molecule able to regulate mitogen-activated protein kinase pathways and the activity of redox-sensitive transcription factors such as Nrf2, AP1, and NFκB. Therefore, increased levels of HNE in the skin, in response to pollutants, likely accelerates skin aging and exacerbates existing skin inflammatory conditions; thus, targeting HNE formation could be an innovative cosmeceutical approach for topical applications.


Assuntos
Poluentes Atmosféricos/toxicidade , Aldeídos/toxicidade , Dermatite Atópica/induzido quimicamente , Material Particulado/toxicidade , Psoríase/induzido quimicamente , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Poluentes Atmosféricos/metabolismo , Aldeídos/metabolismo , Dermatite Atópica/genética , Dermatite Atópica/metabolismo , Dermatite Atópica/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxirredução , Estresse Oxidativo , Ozônio/metabolismo , Ozônio/toxicidade , Psoríase/genética , Psoríase/metabolismo , Psoríase/patologia , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Pele/metabolismo , Pele/patologia , Envelhecimento da Pele/genética , Envelhecimento da Pele/patologia , Poluição por Fumaça de Tabaco/efeitos adversos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Sci Total Environ ; 669: 1043-1052, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30970453

RESUMO

Climate change significantly modifies terrestrial ecosystems and vegetation activity, yet little is known about how climate change and ozone pollution interact to affect forest health. Here we compared the trends of two metrics widely used to protect forests against negative impacts of ozone pollution, the AOT40 (Accumulated Ozone over Threshold of 40 ppb) which only depends on surface air ozone concentrations, and the POD (Phytotoxic Ozone Dose) which relies on the amount of ozone uptaken by plants through stomata. Using a chemistry transport model, driven by anthropogenic emission inventories, we found that European-averaged ground-level ozone concentrations significantly declined (-1.6%) over the time period 2000-2014, following successful control strategies to reduce the ozone precursors emission; as a consequence, the AOT40 metric declined (-22%). In contrast, climate change increased both growing season length (~7 days/decade) and stomatal conductance and thus enhanced the stomatal ozone uptake by forests (5.9%), leading to an overall increase of potential ozone damage on plants, despite the reduction in ozone concentrations. Our results suggest that stomatal-flux based strategies of forest protection against ozone in a changing climate require a proper consideration of the duration of the growing season with a better estimation of start and end of the growing season.


Assuntos
Poluentes Atmosféricos/metabolismo , Poluição do Ar/prevenção & controle , Mudança Climática , Florestas , Ozônio/metabolismo , Árvores/crescimento & desenvolvimento , Monitoramento Ambiental , Europa (Continente) , Estações do Ano , Árvores/metabolismo
7.
Klin Lab Diagn ; 64(3): 132-139, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31012550

RESUMO

Physicochemical differences between О3 oxidation parameters for palmitic and oleic fatty acids (FA) during phylogenesis (evolution) are fundamental for а) production of palmitoleic monounsaturated fatty (MFA), b) formation of carnitine palmitoyltransferase as a FA transporter to mitochondria, and c) in vivo production of oleic MFA under humoral regulatory effect of insulin. In the strive for the best kinetic parameters of biological organisms without a possibility of modifying physicochemical and biochemical reactions in the mitochondrial matrix, the mitochondria can be provided with a substrate that increases energy production efficiency and the amount of ATP. Physicochemical parameters of oleic MFA has become the standard of an oxidation substrate for in vivo energy production; this MFA was synthesized in organisms for millions of years. Environmental influences are the second factor which determines kinetic perfection of biological organisms during phylogenesis. Are these influences always beneficial? Mostly, they are not. However, they largely stimulate adaptive functions of the organism, including the biological function of locomotion, cognitive function and the function of positioning in the environment. Biological, energy and kinetic perfection formed in vivo can be easily destroyed if phylogenetically herbivorous Homo sapiens abuses the diet of carnivorous animals (meat) which was not consumed by him and his ancestors during phylogenesis. This abuse is the major cause of metabolic pandemias in human population. They are: insulin resistance, atherosclerosis and atheromatosis, obesity and nonalcoholic liver disease. The most effective measures preventing metabolic pandemias, cardiac heart disease and myocardial infarction are extremely simple. People should remain herbivorous.


Assuntos
Ácido Oleico/metabolismo , Ozônio/metabolismo , Ácido Palmítico/metabolismo , Animais , Dieta Vegetariana , Humanos , Insulina , Carne
8.
Sci Total Environ ; 665: 929-936, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30893752

RESUMO

Ozone (O3) pollution can alter carbon allocation and reduce tree growth - both above and below ground, but the extent of these effects depends on the variation in soil water and nutrient availability. Here we present the accumulation and allocation of biomass in poplar clone 546 (Populus deltoides cv. '55/56' × P. deltoides cv. 'Imperial') for one growing season at two O3 concentrations (charcoal-filtered air [CF] and non-filtered air + 40 ppb of O3 [E-O3]), two watering regimes (well-watered [WW] and reduced watering at 40% of WW irrigation [RW]) and two soil nitrogen addition treatments (no addition [N0] and the addition of 50 kg N ha-1 year-1 [N50]). We found that the deleterious effects of E-O3 depended on the supply of water and nitrogen. Specifically, when the supplies of water and/or N (WW and/or N50) were abundant, E-O3 significantly reduced whole plant biomass by >15% but had no significant effect on biomass when these supplies were limited (RW and N0). A significant reduction of biomass by E-O3 occurred earlier in fine roots than in other plant organs, indicating greater sensitivity of fine root to E-O3. These results suggest that rising O3 concentrations may not ubiquitously lead to a large reduction in plant biomass since plant growth is often jointly constrained by water and nutrients.


Assuntos
Nitrogênio/análise , Ozônio/metabolismo , Populus/metabolismo , Solo/química , Água/análise , Biomassa , Relação Dose-Resposta a Droga , Ozônio/administração & dosagem , Populus/efeitos dos fármacos , Populus/crescimento & desenvolvimento , Estações do Ano
9.
Environ Pollut ; 247: 586-594, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708321

RESUMO

Around the globe, worsening air pollution is spawning major public health and environmental concerns, especially in the poorest and most populous cities. As a major secondary air pollutant, ozone is a potential risk factor for exacerbated asthma, although the underlying mechanisms remain uncertain. In this study, we aim to investigate the role of ozone on asthma exacerbation using a classic asthmatic model with allergic airway inflammation by treating Balb/c mice with ovalbumin (OVA). Our study shows ozone exposure significantly exacerbated OVA-induced asthmatic phenotypes, including serum immunoglobulin, Th cytokines, inflammatory cell counts, mucus production, airway remodeling, and airway hyper-responsiveness (AHR). Interestingly, expression of transient receptor potential cation channel subfamily V member1 (TRPV1) was also significantly elevated in ozone-exacerbated asthmatic mice and that treatment with TRPV1 antagonist effectively suppressed AHR, airway inflammation and remodeling. The underlying mechanisms of these effects may be associated with suppression of neuropeptide calcitonin gene-related peptide (CGRP) and thymic stromal lymphopoietin (TSLP), an epithelial cell-derived cytokine. Base on the role of TRPV1 in allergic asthma, this study further revealed that inhibition of TRPV1 by TRPV1 antagonist has significant anti-inflammatory effects on ozone-induced asthma exacerbation in this study. Induction of TRPV1 expression may be an important mechanism underlying the increased risks for asthma after exposure to environmental pollutants.


Assuntos
Poluentes Atmosféricos/toxicidade , Asma/induzido quimicamente , Ozônio/toxicidade , Canais de Cátion TRPV/metabolismo , Animais , Asma/metabolismo , Citocinas , Modelos Animais de Doenças , Inflamação , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Ozônio/metabolismo , Sistema Respiratório/metabolismo , Canais de Receptores Transientes de Potencial/metabolismo
10.
J Toxicol Environ Health A ; 82(2): 86-98, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30755101

RESUMO

There is growing interest in understanding how maternal diet might affect the sensitivity of offspring to environmental exposures. Previous studies demonstrated that adult rat offspring (approximately 6-months-old) from dams given a high-fat diet (HFD) prior to, during, and after pregnancy displayed elevated pulmonary responses to an acute ozone (O3) exposure. The aim of this study was to examine the influence of maternal and perinatal HFD on pulmonary and metabolic responses to O3 in male and female young-adult offspring (approximately 3-month old). One-month-old F0 female Long-Evans rats commenced HFD (60% kcal from fat) or control diet (CD; 10.5% kcal from fat) and were bred on PND 72. Offspring were maintained on respective HFD or CD until PND 29 when all groups were switched to CD. The 3-months-old female and male offspring (n = 10/group) were exposed to air or 0.8 ppm O3 for 5hr/day for 2 consecutive days. Maternal and perinatal HFD significantly increased body weight and body fat % in offspring regardless of gender. Ozone exposure, but not maternal and perinatal diet, induced hyperglycemia and glucose intolerance in the offspring. Ozone-induced alterations in pulmonary function were exacerbated by maternal and perinatal HFD in both offspring genders. Pulmonary injury/inflammation markers in response to O3 exposure such as bronchoalveolar lavage fluid total protein, lactate dehydrogenase, total cells, and neutrophils were further augmented in offspring (males>females) from dams fed the HFD. Data suggest that maternal and perinatal HFD may enhance the susceptibility of offspring to O3-induced pulmonary injury and that these effects may be sex-specific.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Pulmão/efeitos dos fármacos , Ozônio/efeitos adversos , Fatores Etários , Animais , Feminino , Lactação , Pulmão/metabolismo , Masculino , Ozônio/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Long-Evans
11.
Bioresour Technol ; 278: 51-56, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30677698

RESUMO

Isoprene, the highly reactive volatile organic compound, is used as monomer for the synthesis of several useful polymers. Its extensive production and usage leads to contamination of air. Once released, it alters the atmospheric chemistry by reacting with hydroxyl radicals (OH) and nitrogen oxides (NOx) to generate tropospheric ozone. Its prolonged exposure causes deleterious effects in human and plants. Therefore, its removal from the contaminated environment through biodegradation, provides a promising remedial solution. In the present study, isoprene utilizing bacteria namely, Pseudomonas sp., Arthrobacter sp., Bacillus sp. Sphingobacterium sp., Sphingobium sp., and Pantoea sp. were isolated and characterized from leaf surface of Madhuca latifolia and Tectona grandis, and also from soils under these plants. Their isoprene degrading capability and kinetics were assessed in batch mode. The isoprene degradation study indicated Pseudomonas sp. to be the most efficient isoprene degrader.


Assuntos
Arthrobacter/metabolismo , Butadienos/metabolismo , Hemiterpenos/metabolismo , Pseudomonas/metabolismo , Biodegradação Ambiental , Cinética , Óxidos de Nitrogênio/metabolismo , Ozônio/metabolismo , Solo
12.
Ecotoxicol Environ Saf ; 171: 805-812, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30660974

RESUMO

Eighteen plant species were screened for ozone (O3) removal in a continuous system. Zamioculcas zamiifolia had the highest O3 removal efficiency. To enhance O3 removal by Z. zamiifolia, adding a compatible endophytic bacteria, Bacillus cereus ERBP into Z. zamiifolia was studied. After operating under an O3 continuous system (150-250 ppb) at a flow rate of 0.3 L min-1 for 80 h, inoculated plants (74%) exhibited higher O3 removal efficiency than non-inoculated ones (53%). In addition, after O3 exposure (80 h), the population of B. cereus ERBP in inoculated plants was significantly increased in both shoots approximately 35 folds and leaves 13 folds compared to inoculated plants without O3 exposure. The results also showed that B. cereus ERBP had the ability to protect Z. zamiifolia against O3 stress conditions. The increase in B. cereus ERBP populations was attributed to the significant increase in ascorbate peroxidase (APX) and catalase (CAT) activity. In addition, increasing B. cereus ERBP populations led to raise total flavonoid contents which is one of antioxidant compounds. Increasing APX, CAT activities, and total flavonoid contents can enhance O3 detoxification in plant tissues. The mechanism of B. cereus ERBP for enhancing O3 phytoremediation was proposed in this study. The results suggested that B. cereus ERBP was a potential tool for alleviating O3 stress on Z. zamiifolia and enhancing O3 phytoremediation efficiency.


Assuntos
Araceae/metabolismo , Bacillus cereus/fisiologia , Ozônio/metabolismo , Antioxidantes/metabolismo , Araceae/enzimologia , Araceae/microbiologia , Ascorbato Peroxidases/metabolismo , Biodegradação Ambiental , Catalase/metabolismo , Flavonoides/metabolismo , Inativação Metabólica , Ozônio/toxicidade
13.
Sci Total Environ ; 656: 681-690, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529971

RESUMO

Tropospheric ozone (O3) is the main secondary pollutant and considered to be the most damaging for growth and productivity. O3 is well known to induce oxidative stress and Reactive Oxygen Species accumulation in leaf tissues. Several mechanisms have been suggested to enable trees to cope with such stress; however, their relative contribution to O3 tolerance is still unclear. Here, ten Euramerican poplar genotypes (Populus deltoides × nigra) were investigated regarding their response to 120 ppb of O3 for 3 weeks in order to determine main mechanisms and identify the key traits and strategies linked to a better tolerance to O3-induced oxidative stress. Results showed that ascorbate peroxidase and ascorbate regeneration through monodehydroascorbate reductase are the main determinants of O3 tolerance in Euramerican poplar, in protecting photosynthesis capacity from oxidative stress and therefore, maintaining growth and productivity. Besides, stomatal closure was harmful in sensitive genotypes, suggesting that avoiding strategy can be further deleterious under chronic ozone. Finally, O3-induced early senescence appeared essential when up scaling leaf-level mechanistic response to whole-plant productivity, in fine-tuning resource reallocation and photosynthesis area.


Assuntos
Poluentes Atmosféricos/metabolismo , Genótipo , Estresse Oxidativo , Ozônio/metabolismo , Populus/fisiologia , Fotossíntese , Folhas de Planta/fisiologia , Populus/genética
14.
Sci Total Environ ; 657: 379-390, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30550902

RESUMO

There is a lack of knowledge about the possibility that plants facing abiotic stressors, such as drought, have an altered perception of a pulse of O3 and incur in alterations of their signalling network. This poses some concerns as to whether defensive strategy to cope episodic O3 peaks in healthy plants may fail under stress. In this study, a set of saplings of two Mediterranean deciduous species, Quercus cerris and Q. pubescens, was subjected to water withholding (20% of daily evapotranspiration for 15 days) while another set was kept well-watered. Saplings were then subjected to a pulse of O3 (200 nl l-1 for 5 h) or maintained in filtered air. Q. pubescens had a more severe decline of photosynthesis and leaf PDΨw (about -65% and 5-fold lower than in well-watered ones) and events of cell death were observed under drought when compared to Q. cerris, which is supportive for a higher sensitivity to drought exhibited by this species. When O3 was applied after drought, patterns of signalling compounds were altered in both species. Only in Q. pubescens, the typical O3-induced accumulation of apoplastic reactive oxygen species, which is the first necessary step for the activation of signalling cascade, was completely lost. In Q. cerris the most frequent changes encompassed the weakening of peaks of key signalling molecules (ethylene and salicylic acid), whereas in Q. pubescens both delayed (salicylic and jasmonic acid) or weakened (ethylene and salicylic acid) peaks were observed. This is translated to a higher ability of Q. cerris to maintain a prompt activation of defensive reaction to counteract oxidative damage due to the pollutant. Our results reveal the complexity of the signalling network in plants facing multiple stresses and highlight the need to further investigate possible alteration of defensive mechanism of tree species to predict their behavior.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Secas , Ozônio/efeitos adversos , Quercus/fisiologia , Região do Mediterrâneo , Ozônio/metabolismo , Quercus/efeitos dos fármacos , Especificidade da Espécie , Árvores/efeitos dos fármacos , Árvores/fisiologia
15.
Sci Total Environ ; 657: 568-576, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30550919

RESUMO

Tropospheric ozone (O3) is the most important gaseous pollutant and induces a mass of negative impacts on vegetation at functional and genic levels. The aim of the present study was to investigate the role of reactive oxygen species and signalling molecules in sage plants exposed to O3 (200 ppb, 5 h). Ozone exposure induced only a transient oxidative burst, as confirmed by the rapid peak of anion superoxide during the first hours of exposure (+16% compared to controls). The spontaneous reaction of O3 with membrane fatty acids stimulates peroxidative processes, as demonstrated by the rise of thiobarbituric acid reactive substances concentration starting after 1 h of exposure (+25%). The formation of lipid-based signalling molecules (e.g. jasmonic acid) may be regarded as a sort of O3-perception. The concomitant accumulation of salicylic acid suggests that sage responds early to O3 by inducing cellular antioxidants mechanisms in order to minimize O3-oxidative burst. The transient increase of abscisic acid (+25% at the end of the treatment) twinned with the maximal ethylene emission (about two-fold higher than controls) could be interpreted as a first attempt by plants to regulate the signalling responses induced by O3. In order to investigate the involvement of transcription factors in managing oxidative protection, BLASTX analysis against the Salvia miltiorrhiza sequence genome was carried out using Arabidopsis thaliana WRKY sequences as queries. Six gene sequences were identified for sage WRKYs and their relative gene expression analyses were characterized. WRKY4, WRKY5, WRKY11 and WRKY46 were up-regulated by O3 at 2 and 5 h of exposure and they showed similarity with AtWRKY48, AtWRKY22 and AtWRKY53 in A. thaliana. These results suggest that WRKYs could play a pivotal role in the signalling mechanisms during the responses of plants to O3.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Ozônio/metabolismo , Reguladores de Crescimento de Planta/biossíntese , Explosão Respiratória/efeitos dos fármacos , Salvia officinalis/fisiologia , Transdução de Sinais/efeitos dos fármacos , Proteínas de Arabidopsis/metabolismo , Salvia officinalis/efeitos dos fármacos , Salvia officinalis/genética , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
16.
BMC Plant Biol ; 18(1): 358, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558543

RESUMO

BACKGROUND: Understanding the mechanisms involved in climacteric fruit ripening is key to improve fruit harvest quality and postharvest performance. Kiwifruit (Actinidia deliciosa cv. 'Hayward') ripening involves a series of metabolic changes regulated by ethylene. Although 1-methylcyclopropene (1-MCP, inhibitor of ethylene action) or ozone (O3) exposure suppresses ethylene-related kiwifruit ripening, how these molecules interact during ripening is unknown. RESULTS: Harvested 'Hayward' kiwifruits were treated with 1-MCP and exposed to ethylene-free cold storage (0 °C, RH 95%) with ambient atmosphere (control) or atmosphere enriched with O3 (0.3 µL L- 1) for up to 6 months. Their subsequent ripening performance at 20 °C (90% RH) was characterized. Treatment with either 1-MCP or O3 inhibited endogenous ethylene biosynthesis and delayed fruit ripening at 20 °C. 1-MCP and O3 in combination severely inhibited kiwifruit ripening, significantly extending fruit storage potential. To characterize ethylene sensitivity of kiwifruit following 1-MCP and O3 treatments, fruit were exposed to exogenous ethylene (100 µL L- 1, 24 h) upon transfer to 20 °C following 4 and 6 months of cold storage. Exogenous ethylene treatment restored ethylene biosynthesis in fruit previously exposed in an O3-enriched atmosphere. Comparative proteomics analysis showed separate kiwifruit ripening responses, unraveled common 1-MCP- and O3-dependent metabolic pathways and identified specific proteins associated with these different ripening behaviors. Protein components that were differentially expressed following exogenous ethylene exposure after 1-MCP or O3 treatment were identified and their protein-protein interaction networks were determined. The expression of several kiwifruit ripening related genes, such as 1-aminocyclopropane-1-carboxylic acid oxidase (ACO1), ethylene receptor (ETR1), lipoxygenase (LOX1), geranylgeranyl diphosphate synthase (GGP1), and expansin (EXP2), was strongly affected by O3, 1-MCP, their combination, and exogenously applied ethylene. CONCLUSIONS: Our findings suggest that the combination of 1-MCP and O3 functions as a robust repressive modulator of kiwifruit ripening and provide new insight into the metabolic events underlying ethylene-induced and ethylene-independent ripening outcomes.


Assuntos
Actinidia/fisiologia , Ciclopropanos/farmacologia , Etilenos/farmacologia , Frutas/fisiologia , Ozônio/farmacologia , Actinidia/efeitos dos fármacos , Etilenos/metabolismo , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ozônio/metabolismo , Proteínas de Plantas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Mar Drugs ; 16(9)2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30223486

RESUMO

Solar radiation represents a key abiotic factor in the evolution of life in the oceans. In general, marine, biota-particularly in euphotic and dysphotic zones-depends directly or indirectly on light, but ultraviolet radiation (UV-R) can damage vital molecular machineries. UV-R induces the formation of reactive oxygen species (ROS) and impairs intracellular structures and enzymatic reactions. It can also affect organismal physiologies and eventually alter trophic chains at the ecosystem level. In Antarctica, physical drivers, such as sunlight, sea-ice, seasonality and low temperature are particularly influencing as compared to other regions. The springtime ozone depletion over the Southern Ocean makes organisms be more vulnerable to UV-R. Nonetheless, Antarctic species seem to possess analogous UV photoprotection and repair mechanisms as those found in organisms from other latitudes. The lack of data on species-specific responses towards increased UV-B still limits the understanding about the ecological impact and the tolerance levels related to ozone depletion in this region. The photobiology of Antarctic biota is largely unknown, in spite of representing a highly promising reservoir in the discovery of novel cosmeceutical products. This review compiles the most relevant information on photoprotection and UV-repair processes described in organisms from the Southern Ocean, in the context of this unique marine polar environment.


Assuntos
Aclimatação/fisiologia , Organismos Aquáticos/fisiologia , Evolução Biológica , Ozônio/metabolismo , Raios Ultravioleta/efeitos adversos , Regiões Antárticas , Organismos Aquáticos/metabolismo , Cosmecêuticos/química , Cosmecêuticos/isolamento & purificação , Cosmecêuticos/farmacologia , Descoberta de Drogas , Humanos , Camada de Gelo , Oceanos e Mares , Ozônio/química , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação
18.
Environ Pollut ; 243(Pt A): 163-176, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30172122

RESUMO

Outdoor air pollution is considered as the most serious environmental problem for human health, associated with some million deaths worldwide per year. Cities have to cope with the challenges due to poor air quality impacting human health and citizen well-being. According to an analysis in the framework of this study, the annual mean concentrations of tropospheric ozone (O3) have been increasing by on average 0.16 ppb year-1 in cities across the globe over the time period 1995-2014. Green urban infrastructure can improve air quality by removing O3. To efficiently reduce O3 in cities, it is important to define suitable urban forest management, including proper species selection, with focus on the removal ability of O3 and other air pollutants, biogenic emission rates, allergenic effects and maintenance requirements. This study reanalyzes the literature to i) quantify O3 removal by urban vegetation categorized into trees/shrubs and green roofs; ii) rank 95 urban plant species based on the ability to maximize air quality and minimize disservices, and iii) provide novel insights on the management of urban green spaces to maximize urban air quality. Trees showed higher O3 removal capacity (3.4 g m-2 year-1 on average) than green roofs (2.9 g m-2 year-1 as average removal rate), with lower installation and maintenance costs (around 10 times). To overcome present gaps and uncertainties, a novel Species-specific Air Quality Index (S-AQI) of suitability to air quality improvement is proposed for tree/shrub species. We recommend city planners to select species with an S-AQI>8, i.e. with high O3 removal capacity, O3-tolerant, resistant to pests and diseases, tolerant to drought and non-allergenic (e.g. Acer sp., Carpinus sp., Larix decidua, Prunus sp.). Green roofs can be used to supplement urban trees in improving air quality in cities. Urban vegetation, as a cost-effective and nature-based approach, aids in meeting clean air standards and should be taken into account by policy-makers.


Assuntos
Poluição do Ar/prevenção & controle , Cidades , Ozônio/análise , Ozônio/metabolismo , Árvores/química , Árvores/metabolismo , Poluentes Atmosféricos/análise , Biodegradação Ambiental , Humanos , Especificidade da Espécie
19.
Plant Cell Environ ; 41(12): 2882-2898, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30107647

RESUMO

Monitoring of ozone damage to crops plays an increasingly important role for the food security of many developing countries. Ethylenediurea (EDU) could be a tool to assess ozone damage to vegetation on field scale, but its physiological mode of action remains unclear. This study investigated mechanisms underlying the ozone-protection effect of EDU in controlled chamber experiments. Ozone sensitive and tolerant rice genotypes were exposed to ozone (108 ppb, 7 hr day-1 ) and control conditions. EDU alleviated ozone effects on plant morphology, foliar symptoms, lipid peroxidation, and photosynthetic parameters in sensitive genotypes. Transcriptome profiling by RNA sequencing revealed that thousands of genes responded to ozone in a sensitive variety, but almost none responded to EDU. Significant interactions between ozone and EDU application occurred mostly in ozone responsive genes, in which up-regulation was mitigated by EDU application. Further experiments documented ozone degrading properties of EDU, as well as EDU deposits on leaf surfaces possibly related to surface protection. EDU application did not mitigate the reaction of plants to other abiotic stresses, including iron toxicity, zinc deficiency, and salinity. This study provided evidence that EDU is a surface protectant that specifically mitigates ozone stress without interfering directly with the plants' stress response systems.


Assuntos
Oryza/metabolismo , Ozônio/antagonistas & inibidores , Compostos de Fenilureia/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ferro/metabolismo , Microscopia Eletrônica de Varredura , Oryza/efeitos dos fármacos , Ozônio/metabolismo , Fotossíntese , Estresse Salino , Estresse Fisiológico/efeitos dos fármacos , Zinco/deficiência
20.
Int J Biol Macromol ; 119: 1276-1285, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30096397

RESUMO

Ozone has been known for several decades, with its antiseptic and therapeutic effects determined by the hormesis theory. It is shown that the therapeutic efficacy of ozone therapy may be partly due to the controlled and moderate oxidative stress produced by the reaction of ozone with several biological components. In this study, the effect of ozone on healthy human hemoglobin (Hb) in the whole blood environment (in the presence of antioxidants) and in the purified form (in the absence of antioxidants) is investigated using a number of different techniques including intrinsic fluorescence, circular dichroism and UV-VIS absorption spectroscopy as well as SDS- and Native-PAGE and dynamic light scattering. The results show that the presence of antioxidants prevents damage to Hb while its absence means that as the exposure to ozone is increased, Hb is increasingly damaged. These results highlight the importance for the use of appropriate doses of ozone, for patients with different diseases and hence antioxidant levels, in autohemotherapy.


Assuntos
Antioxidantes/metabolismo , Hemoglobinas/metabolismo , Ozônio/metabolismo , Hemoglobinas/química , Hemoglobinas/uso terapêutico , Humanos , Masculino , Multimerização Proteica , Estrutura Quaternária de Proteína
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