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1.
J Sci Food Agric ; 104(9): 4939-4949, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38314878

RESUMO

Cacti are a distinguished group of plants that stand out for their great nutritional values, diverse uses, and unique morphology, allowing them to grow and thrive under different conditions such as dry, xeric, and even low-temperature environments. The world is going through significant climate changes that are affecting the agriculture system. Therefore, sustainable and multifunctional crops, as many species of the Cactaceae family are, might be a good alternative in the near future. In this work, the uses of cacti in human food were analyzed through a scientific prospection from the point of view of their temporal and spatial distribution and potential uses. Brazil is the country with more publications related to the scope of this work, followed by Mexico. The presence of cacti in these countries can influence their interest in these species, which might reflect the results encountered in this study. The uses and ethnobotanical applications of cacti vary in different countries worldwide. Cactus is consumed fresh (in salads), in preparations (jams and sweets), and juices, being also present in traditional dishes in countries like Mexico. This study emphasizes cacti's importance in people's diets and ongoing world changes. Their ability to thrive even in hot environments with low water resources will lead to a greater focus on these species in the upcoming years. Furthermore, these plants have great flavor and contain several beneficial chemical compounds with desirable nutritional and health properties. Therefore, knowledge dissemination combined with technological innovations will allow greater use of these multifunctional species for human consumption. © 2024 Society of Chemical Industry.


Assuntos
Cactaceae , Cactaceae/química , Cactaceae/crescimento & desenvolvimento , Humanos , México , Brasil , Valor Nutritivo , Etnobotânica
2.
An Acad Bras Cienc ; 95(1): e20191295, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36946799

RESUMO

The ground beetle, Neoaulacoryssus speciosus (Coleoptera: Carabidae) is of high relevance to field because it has been recorded as a pest of seeds and young plants of vegetables and other crops and a predator in agricultural crops, forest and weeds in Brazil. However, natural habitat changes are increasing agriculture and forest insect outbreaks in urban areas. A N. speciosus population outbreak occurred in October and November 2018 simultaneously in 12 neighboring municipalities at the beginning of the rainy season in the northern region of Minas Gerais State, Brazil. The objectives of this study were to report a sudden and simultaneous population outbreak of N. speciosus and to describe the factors of habitat change that could have contributed to this invasion in 12 municipalities in the northern region of Minas Gerais State in the Caatinga biome of Brazil. In addition, female and male genitals were described and illustrated, the scientific classification revised and common names of N. speciosus listed. Thousands of males and females of N. speciosus agglomerated in shady, humid places during the day and night for about 15 days. Neoaulacoryssus speciosus has been identified and illustrated, its scientific classification revised and four common names listed for this species.


Assuntos
Besouros , Florestas , Animais , Masculino , Feminino , Cidades , Surtos de Doenças , Chuva , Brasil/epidemiologia
3.
Phytother Res ; 36(4): 1459-1506, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35229374

RESUMO

Terpenes are one of the most abundant classes of secondary metabolites produced by plants and can be divided based on the number of isoprene units (C5 ) in monoterpenes (2 units-C10 ), sesquiterpenes (3 units-C15 ), diterpenes (4 units-C20 ), triterpenes (6 units-C30 ), etc. Chemically, triterpenes are classified based on their structural skeleton including lanostanes, euphanes, cycloartanes, ursanes, oleananes, lupanes, tirucallanes, cucurbitanes, dammaranes, baccharanes, friedelanes, hopanes, serratanes etc. Additionally, glycosylated (saponins) or highly oxidated/degraded (limonoids) triterpenes could be found in nature. The antiinflammatory effect and action as immunomodulators of these secondary metabolites have been demonstrated in different studies. This review reports an overview of articles published in the last 15 years (from 2006 to 2021 using PubMed and SciFinder database) describing the antiinflammatory effects of different triterpenes with their presumed mechanism of action, suggesting that triterpenes could be appointed as natural products with future pharmaceutical applicability.


Assuntos
Produtos Biológicos , Saponinas , Triterpenos , Anti-Inflamatórios/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Estrutura Molecular , Plantas , Triterpenos/química , Triterpenos/farmacologia
4.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361938

RESUMO

Light composition modulates plant growth and defenses, thus influencing plant-pathogen interactions. We investigated the effects of different light-emitting diode (LED) red (R) (665 nm) and blue (B) (470 nm) light combinations on Actinidia chinensis performance by evaluating biometric parameters, chlorophyll a fluorescence, gas exchange and photosynthesis-related gene expression. Moreover, the influence of light on the infection by Pseudomonas syringae pv. actinidiae (Psa), the etiological agent of bacterial canker of kiwifruit, was investigated. Our study shows that 50%R-50%B (50R) and 25%R-75%B (25R) lead to the highest PSII efficiency and photosynthetic rate, but are the least effective in controlling the endophytic colonization of the host by Psa. Monochromatic red light severely reduced ΦPSII, ETR, Pn, TSS and photosynthesis-related genes expression, and both monochromatic lights lead to a reduction of DW and pigments content. Monochromatic blue light was the only treatment significantly reducing disease symptoms but did not reduce bacterial endophytic population. Our results suggest that monochromatic blue light reduces infection primarily by modulating Psa virulence more than host plant defenses.


Assuntos
Actinidia , Pseudomonas syringae , Actinidia/genética , Clorofila A , Doenças das Plantas/microbiologia , Virulência
5.
Int J Mol Sci ; 23(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36362399

RESUMO

Environmental stress triggered by climate change can alter the plant's metabolite profile, which affects its physiology and performance. This is particularly important in medicinal species because their economic value depends on the richness of their phytocompounds. We aimed to characterize how water deficit modulated the medicinal species Melia azedarach's lipophilic profile and antioxidant status. Young plants were exposed to water deficit for 20 days, and lipophilic metabolite profile and the antioxidant capacity were evaluated. Leaves of M. azedarach are rich in important fatty acids and oleamide. Water deficit increased the radical scavenging capacity, total phenol, flavonoids, and catechol pools, and the accumulation of ß-sitosterol, myo-inositol, succinic acid, sucrose, d-glucose and derivatives, d-psicofuranose, d-(+)-fructofuranose, and the fatty acids stearic, α-linolenic, linoleic and palmitic acids. These responses are relevant to protecting the plant against climate change-related stress and also increase the nutritional and antioxidant quality of M. azedarach leaves.


Assuntos
Melia azedarach , Plantas Medicinais , Melia azedarach/química , Antioxidantes , Água , Extratos Vegetais/química , Compostos Fitoquímicos , Folhas de Planta , Ácidos Graxos
6.
Molecules ; 26(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800273

RESUMO

Pseudomonas syringae pv. actinidiae (Psa) is the pathogenic agent responsible for the bacterial canker of kiwifruit (BCK) leading to major losses in kiwifruit productions. No effective treatments and measures have yet been found to control this disease. Despite antimicrobial peptides (AMPs) having been successfully used for the control of several pathogenic bacteria, few studies have focused on the use of AMPs against Psa. In this study, the potential of six AMPs (BP100, RW-BP100, CA-M, 3.1, D4E1, and Dhvar-5) to control Psa was investigated. The minimal inhibitory and bactericidal concentrations (MIC and MBC) were determined and membrane damaging capacity was evaluated by flow cytometry analysis. Among the tested AMPs, the higher inhibitory and bactericidal capacity was observed for BP100 and CA-M with MIC of 3.4 and 3.4-6.2 µM, respectively and MBC 3.4-10 µM for both. Flow cytometry assays suggested a faster membrane permeation for peptide 3.1, in comparison with the other AMPs studied. Peptide mixtures were also tested, disclosing the high efficiency of BP100:3.1 at low concentration to reduce Psa viability. These results highlight the potential interest of AMP mixtures against Psa, and 3.1 as an antimicrobial molecule that can improve other treatments in synergic action.


Assuntos
Proteínas Citotóxicas Formadoras de Poros/farmacologia , Pseudomonas syringae/efeitos dos fármacos , Actinidia , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sinergismo Farmacológico , Frutas/efeitos dos fármacos , Histatinas/farmacologia , Oligopeptídeos/farmacologia , Doenças das Plantas/microbiologia , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Pseudomonas syringae/metabolismo , Pseudomonas syringae/patogenicidade
7.
Planta ; 249(5): 1583-1598, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30771046

RESUMO

MAIN CONCLUSION: A water-deficit period, leading to stomatal control and overexpression of protective proteins (sHSP and DHN), contributes to olive´s tolerance to later imposed stress episodes. Aquaporins modulation is important in olive recovery. Olive is traditionally cultivated in dry farming or in high water demanding irrigated orchards. The impact of climate change on these orchards remains to unveil, as heat and drought episodes are increasing in the Mediterranean region. To understand how young plants face such stress episodes, olive plants growing in pots were exposed to well-irrigated and non-irrigated treatments. Subsequently, plants from each treatment were either exposed to 40 °C for 2 h or remained under control temperature. After treatments, all plants were allowed to grow under well-irrigated conditions (recovery). Leaves were compared for photosynthesis, relative water content, mineral status, pigments, carbohydrates, cell membrane permeability, lipid peroxidation and expression of the protective proteins' dehydrin (OeDHN1), heat-shock proteins (OeHSP18.3), and aquaporins (OePIP1.1 and OePIP2.1). Non-irrigation, whilst increasing carbohydrates, reduced some photosynthetic parameters to values below the ones of the well-irrigated plants. However, when both groups of plants were exposed to heat, well-irrigated plants suffered more drastic decreases of net CO2 assimilation rate and chlorophyll b than non-irrigated plants. Overall, OeDHN1 and OeHSP18.3 expression, which was increased in non-irrigated treatment, was potentiated by heat, possibly to counteract the increase of lipid peroxidation and loss of membrane integrity. Plants recovered similarly from both irrigation and temperature treatments, and recovery was associated with increased aquaporin expression in plants exposed to one type of stress (drought or heat). These data represent an important contribution for further understanding how dry-farming olive will cope with drought and heat episodes.


Assuntos
Olea/metabolismo , Olea/fisiologia , Fotossíntese/fisiologia , Irrigação Agrícola , Aquaporinas/metabolismo , Mudança Climática , Secas , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Proteínas de Plantas/metabolismo
8.
Intern Med J ; 49(5): 644-649, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30230151

RESUMO

BACKGROUND: Intercostal chest catheter (ICC) insertion is a common hospital procedure with attendant risks including life-threatening complications such as pneumothorax and visceral damage. AIM: To investigate the effect of a quality improvement (QI) initiative on complications associated with inpatient thoracostomy tube insertion. METHODS: Following an audit of ICC complications in inpatients over a 2-year period we implemented a comprehensive QI programme. This involved formal training in and mandatory use of thoracic ultrasound, standardisation of the procedure and documentation, a dedicated procedure room with nurses trained in assisting ICC insertion and senior supervision for medical staff. An audit over 2 years post-implementation of the QI protocol was compared with pre-implementation results. RESULTS: A total of 103 cases were reviewed pre-implementation and 105 cases were reviewed post-implementation of the QI programme. All procedures following the QI initiative were image guided compared to 23.3% of cases pre-implementation. The rate of developing a pneumothorax requiring intervention post-implementation was less than pre-implementation (1.9% vs 5.8% (P = 0.023). Post-implementation, there were no instances of dry taps, viscera perforation, clinically significant bleeding or wrong side ICC insertion and documentation improved. CONCLUSION: QI initiative applied to thoracostomy tube insertion in hospital inpatients can reduce complications and improve procedure documentation.


Assuntos
Tubos Torácicos/normas , Hospitalização , Segurança do Paciente/normas , Pneumotórax/prevenção & controle , Melhoria de Qualidade/normas , Toracostomia/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Tubos Torácicos/efeitos adversos , Auditoria Clínica/métodos , Auditoria Clínica/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Pneumotórax/diagnóstico , Pneumotórax/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Toracostomia/efeitos adversos , Resultado do Tratamento , Adulto Jovem
9.
J Appl Toxicol ; 39(7): 1057-1065, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30883852

RESUMO

Occupational environments are major exposure routes to Cr(VI). However, Cr(VI) may also establish in bone tissues by ingestion or through Cr containing orthopaedic prostheses that, due to wear and corrosion, may release metal particles and ions potentially affecting bone tissue. The aim of this work was to evaluate the effects of clinically relevant concentrations of Cr(VI) in human osteoblasts, by integrating genotoxic effects, evaluated by the comet assay and cytokinesis-blocked micronucleus assay (scoring the presence of micronucleus, nucleoplasmic bridges and nuclear division index), with the effects on cell cycle and cell viability. Human osteoblasts MG-63 were in vitro exposed to Cr(VI) at concentrations ranging from 0.1 to 5 µm, for 24 and 48 hours. Results pointed out to a decrease of cell viability for both time exposures in a time- and dose-dependent manner, which was related to cell cycle arrest and DNA damage. Chromosome abnormalities were also observed. Hence, these data suggest that cells arrested in the cell division with DNA damage may have followed cell death pathways, while some surviving ones still revealed DNA damage at chromosome level indicating abnormal cell division progression. In conclusion, Cr(VI) induced cytotoxic and genotoxic effects in human bone cells at concentrations that could be found in patients with metal-on-metal prostheses. In addition, the early onset of genotoxic damage induced by Cr(VI) at low concentrations after 24 hours of cell exposure alert to the relevance of periodic monitoring of patients for genotoxicity diagnosis after implantation of prostheses before clinical symptoms appear.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cromo/toxicidade , Dano ao DNA , Poluentes Ambientais/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Osteoblastos/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Humanos , Testes para Micronúcleos , Osteoblastos/patologia
10.
J Proteome Res ; 17(4): 1636-1646, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29498529

RESUMO

The expansion of biomedical and therapeutic applications of silver nanoparticles (AgNPs) raises the need to further understand their biological effects on human cells. In this work, NMR metabolomics has been applied to reveal the metabolic effects of AgNPs toward human hepatoma (HepG2) cells, which are relevant with respect to nanoparticle accumulation and detoxification. Cellular responses to widely disseminated citrate-coated AgNPs (Cit30) and to emergent biogenic AgNPs prepared using an aqueous plant extract as reducing and stabilizing agent (GS30) have been compared with a view to assess the influence of nanoparticle coating on the metabolic effects produced. Subtoxic concentrations (IC5 and IC20) of both nanoparticle types caused profound changes in the cellular metabolome, suggesting adaptations in energy production processes (glucose metabolism and the phosphocreatine system), antioxidant defenses, protein degradation and lipid metabolism. These signatures were proposed to reflect mainly metabolism-mediated protective mechanisms and were found to be largely common to Cit30 and GS30 AgNPs, although differences in the magnitude of response, not captured by conventional cytotoxicity assessment, were detected. Overall, this study highlights the value of NMR metabolomics for revealing subtoxic biological effects and helping to understand cell-nanomaterial interactions.


Assuntos
Fígado/metabolismo , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Ácido Cítrico/farmacologia , Excipientes/farmacologia , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Substâncias Redutoras/farmacologia
11.
Arch Toxicol ; 92(3): 1205-1214, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29270805

RESUMO

Osteosarcoma chemotherapy is often limited by chemoresistance, resulting in poor prognosis. Combined chemotherapy could, therefore, be used to prevent resistance to chemotherapeutics. Here, the effects of fisetin on osteosarcoma cells were investigated, as well as cytostatic potential in combination with the anti-cancer drug etoposide. For this, different osteosarcoma cell lines were treated with fisetin, with etoposide and with respective combinations. Fisetin was associated with decrease in colony formation in Saos-2 and in U2OS cells but not in MG-63 cells. Notwithstanding, upon evaluation of cellular growth by crystal violet assay, MG-63 and Saos-2 cells showed decreased cell proliferation at 40 and 20 µM fisetin, respectively. Depending on the relative concentrations, fisetin:etoposide combinations showed negative-to-positive interactions on the inhibition of cell proliferation. In addition, fisetin treatment up to 50 µM for 48 h resulted in G2-phase cell cycle arrest. Regardless of the combination, fisetin:etoposide increased % cells in G2-phase and decreased % cells in G1-phase. In addition, mixtures with more positive combined effects induced increased % cells in S-phase. Compared to etoposide treatment, these combinations resulted in decreased levels of cyclins B1 and E1, pointing to the role of these regulators in fisetin-induced cell cycle arrest. In conclusion, these results show that the combination of fisetin with etoposide has higher anti-proliferative effects in osteosarcoma associated with cell cycle arrest, allowing the use of lower doses of the chemotherapeutic agent, which has important implications for osteosarcoma treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina B1/genética , Ciclina E/genética , Etoposídeo/administração & dosagem , Flavonoides/administração & dosagem , Flavonóis , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Oncogênicas/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Ensaio Tumoral de Célula-Tronco
12.
J Toxicol Environ Health A ; 81(15): 675-690, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29939837

RESUMO

Silver nanoparticles (AgNP), with their important properties, are being used in a range of sectors from industry to medicine, leading to increased human exposure. Hence, their toxicity potential needs to be comprehensively evaluated. It was postulated that within small-sized (≤20 nm) polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNP), minor size differences may significantly induce different toxicity profiles and involve varying cellular pathways. Therefore, the aim of this study was to examine the influence of differing size AgNP with 10 nm (AgNP10) and 20 nm (AgNP20) (up to 100 µg/ml), as well as to ionic silver as AgNO3 for 24 and 48 h, using the human lung cell line A549. The effects on cell viability, proliferation, apoptosis, DNA damage and cell cycle dynamics were assessed. Results for both time periods showed that for low concentrations (<5 µg/ml), AgNP20 were more cytotoxic than AgNP10, however, at higher doses, AgNP10 exhibited higher toxicity. For concentrations >50 µg/ml, AgNP10 induced severe DNA damage (comet class 3-4), cell cycle arrest at G2 phase and late-stage apoptosis, while AgNP20 induced cell cycle arrest at S phase and an increase in the percentage sub-G1, which did not recover after 48 h, and late-stage apoptosis/necrosis. In longer-term exposures, the greater impairment in colony formation due to AgNP exposure than to silver ion supports that nanotoxicity is not exclusively due to the released ion. Data suggest that toxicity mediated by small AgNP (≤20 nm) in lung cells is not only dependent on the level of particle internalization, but also on AgNP size and concentration, which may involve varying pathways as targets.


Assuntos
Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Povidona/química , Nitrato de Prata/toxicidade , Prata/toxicidade , Células A549 , Humanos , Tamanho da Partícula
13.
J Toxicol Environ Health A ; 81(15): 705-717, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29913117

RESUMO

Cadmium (Cd) accumulation is known to occur predominantly in kidney and liver; however, low-level long-term exposure to Cd may also result in bone damage. Few studies have addressed Cd-induced toxicity in osteoblasts, particularly upon cell mitochondrial energy processing and putative associations with oxidative stress in bone. To assess the influence of Cd treatment on mitochondrial function and oxidative status in osteoblast cells, human MG-63 cells were treated with Cd (up to 65 µM) for 24 or 48 h. Intracellular reactive oxygen species (ROS), lipid and protein oxidation and antioxidant defense mechanisms such as total antioxidant activity (TAA) and gene expression of antioxidant enzymes were analyzed. In addition, Cd-induced effects on mitochondrial function were assessed by analyzing the activity of enzymes involved in mitochondrial respiration, membrane potential (ΔΨm), mitochondrial morphology and adenylate energy charge. Treatment with Cd increased oxidative stress, concomitantly with lipid and protein oxidation. Real-time polymerase chain reaction (qRT-PCR) analyses of antioxidant genes catalase (CAT), glutathione peroxidase 1 (GPX1), glutathione S-reductase (GSR), and superoxide dismutase (SOD1 and SOD2) exhibited a trend toward decrease in transcripts in Cd-stressed cells, particularly a downregulation of GSR. Longer treatment with Cd (48 h) resulted in energy charge states significantly below those commonly observed in living cells. Mitochondrial function was affected by ΔΨm reduction. Inhibition of mitochondrial respiratory chain enzymes and citrate synthase also occurred following Cd treatment. In conclusion, Cd induced mitochondrial dysfunction which appeared to be associated with oxidative stress in human osteoblasts.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/fisiologia , Osteoblastos , Oxirredução , Proteínas/metabolismo
14.
An Acad Bras Cienc ; 90(4): 3625-3633, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184014

RESUMO

Herbicides can impact non-target metabolic pathways in natural enemies and lead to the reduction of these populations in the field. Behavioral characteristics, morphology and histology of reproductive structures and reproduction of females of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) were evaluated under the effect of the herbicides atrazine, nicosulfuron and the mixture of both. The number of mature oocytes per ovary was lower in females exposed to the herbicides atrazine, nicosulfuron and the mixture of both. Herbicides did not affect the longevity and mortality of P. nigrispinus, therefore, they are selective for this predator. On the other hand, herbicides can cause sublethal effects by affecting the reproduction of predators.


Assuntos
Atrazina/farmacologia , Hemípteros/efeitos dos fármacos , Herbicidas/farmacologia , Piridinas/farmacologia , Compostos de Sulfonilureia/farmacologia , Animais , Atrazina/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Hemípteros/classificação , Herbicidas/administração & dosagem , Piridinas/administração & dosagem , Reprodução/efeitos dos fármacos , Compostos de Sulfonilureia/administração & dosagem
15.
J Environ Sci (China) ; 51: 191-201, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28115130

RESUMO

The antibacterial potential of silver nanoparticles (AgNPs) resulted in their increasing incorporation into consumer, industrial and biomedical products. Therefore, human and environmental exposure to AgNPs (either as an engineered product or a contaminant) supports the emergent research on the features conferring them different toxicity profiles. In this study, 30nm AgNPs coated with citrate or poly(ethylene glycol) (PEG) were used to assess the influence of coating on the effects produced on a human hepatoma cell line (HepG2), namely in terms of viability, apoptosis, apoptotic related genes, cell cycle and cyclins gene expression. Both types of coated AgNPs decreased cell proliferation and viability with a similar toxicity profile. At the concentrations used (11 and 5µg/mL corresponding to IC50 and ~IC10 levels, respectively) the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2 (anti-apoptotic gene) and BAX (pro-apoptotic gene) were both downregulated. Moreover, both AgNPs affected HepG2 cell cycle progression at the higher concentration (11µg/mL) by increasing the percentage of cells in S (synthesis phase) and G2 (Gap 2 phase) phases. Considering the cell-cycle related genes, the expression of cyclin B1 and cyclin E1 genes were decreased. Thus, this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression, cell cycle dynamics and cyclin regulation in a similar way. More research is needed to determine the properties that confer AgNPs at lower toxicity, since their use has proved helpful in several industrial and biomedical contexts.


Assuntos
Antibacterianos/toxicidade , Ácido Cítrico/toxicidade , Substâncias Perigosas/toxicidade , Nanopartículas Metálicas/toxicidade , Polietilenoglicóis/toxicidade , Prata/toxicidade , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas
16.
Arch Biochem Biophys ; 589: 53-61, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26344855

RESUMO

Due to their antimicrobial properties, silver nanoparticles (AgNPs) are increasingly incorporated into consumer goods and medical products. Their potential toxicity to human cells is however a major concern, and there is a need for improved understanding of their effects on cell metabolism and function. Here, Nuclear Magnetic Resonance (NMR) metabolomics was used to investigate the metabolic profile of human epidermis keratinocytes (HaCaT cell line) exposed for 48 h to 30 nm citrate-stabilized spherical AgNPs (10 and 40 µg/mL). Intracellular aqueous extracts, organic extracts and extracellular culture medium were analysed to provide an integrated view of the cellular metabolic response. The specific metabolite variations, highlighted through multivariate analysis and confirmed by spectral integration, suggested that HaCaT cells exposed to AgNPs displayed upregulated glutathione-based antioxidant protection, increased glutaminolysis, downregulated tricarboxylic acid (TCA) cycle activity, energy depletion and cell membrane modification. Importantly, most metabolic changes were apparent in cells exposed to a concentration of AgNPs which did not affect cell viability at significant levels, thus underlying the sensitivity of NMR metabolomics to detect early biochemical events, even in the absence of a clear cytotoxic response. It can be concluded that NMR metabolomics is an important new tool in the field of in vitro nanotoxicology.


Assuntos
Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Metabolômica , Nanopartículas Metálicas/toxicidade , Prata/química , Prata/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citratos/química , Humanos , Queratinócitos/citologia , Espectroscopia de Ressonância Magnética , Mitocôndrias/efeitos dos fármacos , Testes de Toxicidade
17.
Exp Dermatol ; 23(12): 874-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25040310

RESUMO

This review focuses on the photoprotection conferred by lycopene, one of the most potent anti-oxidants. Lycopene has been recently proposed to play a critical role on anticarcinogenic action at different levels. The photoprotective properties of lycopene remain contradictory. Some studies point out a positive and others a negative effect in both in vitro and in vivo models. Currently, researchers recognise that crucial gaps exist in understanding the role of carotenoids as effective modulators of apoptosis, cell cycle dynamics and/or of their in vivo behaviour as cellular anti-oxidants. The development of novel therapeutic strategies for skin disorders depends on our understanding of the molecular mechanism of UV damage on skin cells. The use of several effective phytocompounds, including lycopene, working through preventive and/or corrective pathways in the cell, may be an approach for reducing UV-B-generated damage.


Assuntos
Anticarcinógenos/farmacologia , Carotenoides/farmacologia , Quimioprevenção/métodos , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Junções Comunicantes/efeitos dos fármacos , Humanos , Licopeno , Neoplasias Induzidas por Radiação/prevenção & controle , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos
18.
Nutr Cancer ; 66(2): 325-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24405297

RESUMO

Osteosarcoma is a recalcitrant bone malignancy with poor responsiveness to treatments; therefore, new chemotherapeutic compounds are needed. Sulforaphane (SFN) has been considered a promising chemotherapeutic compound for several types of tumors by inducing apoptosis and cytostasis, but its effects (e.g., genotoxicity) in osteosarcoma cells remains exploratory. In this work, the MG-63 osteosarcoma cell line was exposed to SFN up to 20 µM for 24 and 48 h. SFN induced G2/M phase arrest and decreased nuclear division index, associated with disruption of cytoskeletal organization. Noteworthy, SFN induced a transcriptome response supportive of G2/M phase arrest, namely a decrease in Chk1- and Cdc25C-encoding transcripts, and an increase in Cdk1-encoding transcripts. After 48-h exposure, SFN at a dietary concentration (5 µM) contributed to genomic instability in the MG-63 cells as confirmed by increased number of DNA breaks, clastogenicity, and nuclear and mitotic abnormalities. The increased formation of nucleoplasmic bridges, micronuclei, and apoptotic cells positively correlated with loss of viability. These results suggest that genotoxic damage is an important step for SFN-induced cytotoxicity in MG-63 cells. In conclusion, SFN shows potential to induce genotoxic damage at low concentrations and such potential deserves further investigation in other tumor cell types.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Isotiocianatos/farmacologia , Mitose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Citoesqueleto/química , Humanos , Osteossarcoma/metabolismo , Sulfóxidos
19.
Physiol Plant ; 150(4): 580-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24117924

RESUMO

Eucalyptus plantations are among the most productive forest stands in Portugal and Spain, being mostly used for pulp production and, more recently, as an energy crop. However, the region's Mediterranean climate, with characteristic severe summer drought, negatively affects eucalypt growth and increases mortality. Although the physiological response to water shortage is well characterized for this species, evidence about the plants' recovery ability remains scarce. In order to assess the physiological and biochemical response of Eucalyptus globulus during the recovery phase, two genotypes (AL-18 and AL-10) were submitted to a 3-week water stress period at two different intensities (18 and 25% of field capacity), followed by 1 week of rewatering. Recovery was assessed 1 day and 1 week after rehydration. Drought reduced height, biomass, water potential, NPQ and gas exchange in both genotypes. Contrarily, the levels of pigments, chlorophyll fluorescence parameters (F(v) /F(m) and (φPSII)), MDA and ABA increased. During recovery, the physiological and biochemical profile of stressed plants showed a similar trend: they experienced reversion of altered traits (MDA, ABA, E, g(s), pigments), while other parameters did not recover ((φPSII), NPQ). Furthermore, an overcompensation of CO(2) assimilation was achieved 1 week after rehydration, which was accompanied by greater growth and re-establishment of oxidative balance. Both genotypes were tolerant to the tested conditions, although clonal differences were found. AL-10 was more productive and showed a more rapid and dynamic response to rehydration (namely in carotenoid content, (φPSII) and NPQ) compared to clone AL-18.


Assuntos
Adaptação Fisiológica/fisiologia , Eucalyptus/fisiologia , Estresse Fisiológico/fisiologia , Água/fisiologia , Ácido Abscísico/metabolismo , Adaptação Fisiológica/genética , Biomassa , Dióxido de Carbono/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Cromatografia Líquida de Alta Pressão , Secas , Eucalyptus/genética , Eucalyptus/metabolismo , Genótipo , Malondialdeído/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentação/genética , Pigmentação/fisiologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Especificidade da Espécie , Espectrofotometria , Espectrometria de Massas em Tandem , Fatores de Tempo , Água/metabolismo
20.
Plants (Basel) ; 13(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38931122

RESUMO

The increasing use of photoselective nets (PNs) raises the question of their influence on pollen traits. We aimed to evaluate the effect of PNs (yellow, pearl, and grey) on the pollen of 'Matua' and 'Tomuri' Actinidia deliciosa cultivars. The pollen size and the exine were studied with a light microscopy and a scanning electron microscopy, and the fertility was analysed by a viability assay and in vitro germination. The total soluble proteins (TSPs) and sugars (TSSs) were quantified by colorimetric assays. The molecular structure of the pollen grain's wall was analysed by a Raman spectroscopy. The pollen from the plants under the PNs had a larger width and area and a lower germination rate. No significant changes were observed in the exine's microperforations. The TSP and TSS contents were influenced by the cultivar and PNs (particularly the pearl PN). The Raman spectra of the pollen from the plants grown under the nets presented some bands that significantly shifted from their original position, indicating differences in the vibration modes of the molecules, but no overall changes at their structural or organisation level were found. Our study showed that the PNs could influence several pollen traits, with the pearl PN inducing greater modifications. Our results also support the idea that cultivars affect the outcome of some characteristics.

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