RESUMO
Psammaplins are sulfur containing bromotyrosine alkaloids that have shown antitumor activity through the inhibition of class I histone deacetylases (HDACs). The cytotoxic properties of psammaplin A (1), the parent compound, are related to peroxisome proliferator-activated receptor γ (PPARγ) activation, but the mechanism of action of its analogs psammaplin K (2) and bisaprasin (3) has not been elucidated. In this study, the protective effects against oxidative stress of compounds 1-3, isolated from the sponge Aplysinella rhax, were evaluated in SH-SY5Y cells. The compounds improved cell survival, recovered glutathione (GSH) content, and reduced reactive oxygen species (ROS) release at nanomolar concentrations. Psammaplins restored mitochondrial membrane potential by blocking mitochondrial permeability transition pore opening and reducing cyclophilin D expression. This effect was mediated by the capacity of 1-3 to activate PPARγ, enhancing gene expression of the antioxidant enzymes catalase, nuclear factor E2-related factor 2 (Nrf2), and glutathione peroxidase. Finally, HDAC3 activity was reduced by 1-3 under oxidative stress conditions. This work is the first description of the neuroprotective activity of 1 at low concentrations and the mechanism of action of 2 and 3. Moreover, it links for the first time the previously described effects of 1 in HDAC3 and PPARγ signaling, opening a new research field for the therapeutic potential of this compound family.
Assuntos
Dissulfetos , Estresse Oxidativo , PPAR gama , Tirosina/análogos & derivados , PPAR gama/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Humanos , Animais , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Neurônios/efeitos dos fármacos , Histona Desacetilases/metabolismo , Histona Desacetilases/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Poríferos/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Glutationa/metabolismo , Alcaloides/farmacologia , Alcaloides/química , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/metabolismoRESUMO
Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales) is the main causal agent of chestnut brown rot on sweet chestnut worldwide. The rotting of nuts leads to alterations in the organoleptic qualities and decreased fruit production, resulting in significant economic losses. In 2021, there was an important outbreak of chestnut rot in southern Galicia (Spanish northwest). The profile of secondary metabolites from G. smithogilvyi was studied, especially to determine its capability for producing mycotoxins, as happens with other rotting fungi, due to the possible consequences on the safety of chestnut consumption. Secondary metabolites produced by isolates of G. smithogilvyi growing in potato dextrose agar (PDA) medium were identified using liquid chromatography coupled with high-resolution mass spectrometry. Three metabolites with interesting pharmacological and phyto-toxicological properties were identified based on their exact mass and fragmentation patterns, namely adenosine, oxasetin, and phytosphingosine. The capacity of G. smithogilvyi to produce adenosine in PDA cultures was assessed, finding concentrations ranging from 176 to 834 µg/kg. Similarly, the production of mycotoxins was ruled out, indicating that the consumption of chestnuts with necrotic lesions does not pose a health risk to the consumer in terms of mycotoxins.
Assuntos
Ascomicetos , Micotoxinas , Nozes , Adenosina , Meios de CulturaRESUMO
Cardiovascular diseases and atherosclerosis are currently some of the most widespread diseases of our time. Within cardiovascular disease, coronary artery disease and underlying atherosclerosis were recently linked with systemic and local inflammation. Cyclophilins participate in the initiation and progression of these inflammatory-related diseases. Cyclophilins are released into the extracellular space upon inflammatory stimuli and participate in the pathology of cardiovascular diseases. The cell surface receptor for extracellular cyclophilins, the CD147 receptor, also contributes to coronary artery disease pathogenesis. Nevertheless, the physiological relevance of cyclophilin's family and their receptor in cardiovascular diseases remains unclear. The present study aimed to better understand the role of cyclophilins in cardiovascular artery disease and their relationship with inflammation. Hence, cyclophilins and pro-inflammatory interleukins were measured in the serum of 30 subjects (divided into three groups according to coronary artery disease status: 10 patients with acute coronary syndrome, 10 patients with chronic coronary artery disease, and 10 control volunteers). In addition, cyclophilin levels and CD147 receptor expression were measured in T lymphocytes purified from these subjects. Cyclophilin A, B, and C, pro-inflammatory interleukins, and CD147 membrane expression were significantly elevated in patients with coronary artery disease.
Assuntos
Basigina/metabolismo , Comunicação Celular , Doença da Artéria Coronariana/patologia , Ciclofilinas/metabolismo , Interleucinas/metabolismo , Linfócitos T/imunologia , Estudos de Casos e Controles , Doença da Artéria Coronariana/imunologia , Doença da Artéria Coronariana/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T/metabolismoRESUMO
Seaweeds are a great source of compounds with cytotoxic properties with the potential to be used as anticancer agents. This study evaluated the cytotoxic and proteasome inhibitory activities of 12R-hydroxy-bromosphaerol, 12S-hydroxy-bromosphaerol, and bromosphaerol isolated from Sphaerococcus coronopifolius. The cytotoxicity was evaluated on malignant cell lines (A549, CACO-2, HCT-15, MCF-7, NCI-H226, PC-3, SH-SY5Y, and SK-MEL-28) using the MTT and LDH assays. The ability of compounds to stimulate the production of hydrogen peroxide (H2O2) and to induce mitochondrial dysfunction, the externalization of phosphatidylserine, Caspase-9 activity, and changes in nuclear morphology was also studied on MCF-7 cells. The ability to induce DNA damage was also studied on L929 fibroblasts. The proteasome inhibitory activity was estimated through molecular docking studies. The compounds exhibited IC50 values between 15.35 and 53.34 µM. 12R-hydroxy-bromosphaerol and 12S-hydroxy-bromosphaerol increased the H2O2 levels on MCF-7 cells, and bromosphaerol induced DNA damage on fibroblasts. All compounds promoted a depolarization of mitochondrial membrane potential, Caspase-9 activity, and nuclear condensation and fragmentation. The compounds have been shown to interact with the chymotrypsin-like catalytic site through molecular docking studies; however, only 12S-hydroxy-bromosphaerol evidenced interaction with ALA20 and SER169, key residues of the proteasome catalytic mechanism. Further studies should be outlined to deeply characterize and understand the potential of those bromoditerpenes for anticancer therapeutics.
Assuntos
Antineoplásicos , Neuroblastoma , Rodófitas , Alga Marinha , Humanos , Inibidores de Proteassoma/farmacologia , Peróxido de Hidrogênio/farmacologia , Citotoxinas/farmacologia , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , Fosfatidilserinas/farmacologia , Complexo de Endopeptidases do Proteassoma , Células CACO-2 , Caspase 9 , Quimotripsina/farmacologia , Rodófitas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , ApoptoseRESUMO
Marine natural products have exhibited uncommon chemical structures with relevant antitumor properties highlighting their potential to inspire the development of new anticancer agents. The goal of this work was to study the antitumor activities of the brominated diterpene sphaerodactylomelol, a rare example of the dactylomelane family. Cytotoxicity (10-100 µM; 24 h) was evaluated on tumor cells (A549, CACO-2, HCT-15, MCF-7, NCI-H226, PC-3, SH-SY5Y, SK-ML-28) and the effects estimated by MTT assay. Hydrogen peroxide (H2O2) levels and apoptosis biomarkers (membrane translocation of phosphatidylserine, depolarization of mitochondrial membrane potential, Caspase-9 activity, and DNA condensation and/or fragmentation) were studied in the breast adenocarcinoma cellular model (MCF-7) and its genotoxicity on mouse fibroblasts (L929). Sphaerodactylomelol displayed an IC50 range between 33.04 and 89.41 µM without selective activity for a specific tumor tissue. The cells' viability decrease was accompanied by an increase on H2O2 production, a depolarization of mitochondrial membrane potential and an increase of Caspase-9 activity and DNA fragmentation. However, the DNA damage studies in L929 non-malignant cell line suggested that this compound is not genotoxic for normal fibroblasts. Overall, the results suggest that the cytotoxicity of sphaerodactylomelol seems to be mediated by an increase of H2O2 levels and downstream apoptosis.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Rodófitas/química , Animais , Antineoplásicos/química , Neoplasias da Mama/patologia , Proliferação de Células , Células Cultivadas , Dano ao DNA , Diterpenos/química , Feminino , Humanos , Peróxido de Hidrogênio/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , CamundongosRESUMO
Gracilins are diterpenes derivative, isolated from the marine sponge Spongionella gracilis. Natural gracilins and synthetic derivatives have shown antioxidant, immunosuppressive, and neuroprotective capacities related to the affinity for cyclophilins. The aim of this work was to study anti-inflammatory and immunosuppressive pathways modulated by gracilin L and two synthetic analogues, compound 1 and 2, on a cellular model of inflammation. In this way, the murine BV2 microglia cell line was used. To carry out the experiments, microglia cells were pre-treated with compounds for 1 h and then stimulated with lipopolysaccharide for 24 h to determine reactive oxygen species production, mitochondrial membrane potential, the release of nitric oxide, interleukin-6 and tumor necrosis factor-α and the expression of Nuclear factor-erythroid 2-related factor 2, Nuclear Factor-κB, the inducible nitric oxide synthase, and the cyclophilin A. Finally, a co-culture of neuron SH-SY5Y and microglia BV2 cells was used to check the neuroprotective effect of these compounds. Cyclosporine A was used as a control of effect. The compounds were able to decrease inflammatory mediators, the expression of inflammatory target proteins as well as they activated anti-oxidative mechanism upon inflammatory conditions. For this reason, natural and synthetic gracilins could be interesting for developing anti-inflammatory drugs.
Assuntos
Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclosporina/farmacologia , Diterpenos/química , Humanos , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Laxaphycins are a family of non-ribosomal lipopeptides that have been isolated from several cyanobacteria. Some of these compounds have presented cytotoxic activities, but their mechanism of action is poorly understood. In this work, the already described laxaphycins B and B3, and acyclolaxaphycins B and B3 were isolated from the marine cyanobacteria Anabaena torulosa. Moreover, two new acyclic compounds, [des-(Ala4-Hle5)] acyclolaxaphycins B and B3, were purified from the herviborous gastropod Stylocheilus striatus, with this being the first description of biotransformed laxaphycins. The structure of these new compounds was elucidated, together with the absolute configuration of acyclolaxaphycins B and B3. The bioactivities of the six peptides were determined in SH-SY5Y human neuroblastoma cells. Laxaphycins B and B3 were cytotoxic (IC50: 1.8 and 0.8 µM, respectively) through the induction of apoptosis. In comparison, acyclic laxaphycins did not show cytotoxicity but affected mitochondrial functioning, so their effect on autophagy-related protein expression was analyzed, finding that acyclic peptides affected this process by increasing AMPK phosphorylation and inhibiting mTOR. This work confirms the pro-apoptotic properties of cyclic laxaphycins B and is the first report indicating the effects on autophagy of their acyclic analogs. Moreover, gastropod-derived compounds presented ring opening and amino-acids deletion, a biotransformation that had not been previously described.
Assuntos
Antineoplásicos/farmacologia , Neuroblastoma/tratamento farmacológico , Peptídeos Cíclicos/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Concentração Inibidora 50 , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Peptídeos Cíclicos/química , Fosforilação , Conformação Proteica , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismoRESUMO
The macrolide caniferolide A was isolated from extracts of a culture of the marine-derived actinomycete Streptomyces caniferus, and its ability to ameliorate Alzheimer's disease (AD) hallmarks was determined. The compound reduced neuroinflammatory markers in BV2 microglial cells activated with lipopolysaccharide (LPS), being able to block NFκB-p65 translocation to the nucleus and to activate the Nrf2 pathway. It also produced a decrease in pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α), reactive oxygen species (ROS) and nitric oxide release and inhibited iNOS, JNK, and p38 activities. Moreover, the compound blocked BACE1 activity and attenuated Aß-activation of microglia by drastically diminishing ROS levels. The phosphorylated state of the tau protein was evaluated in SH-SY5Y tau441 cells. Caniferolide A reduced Thr212 and Ser214 phosphorylation by targeting p38 and JNK MAPK kinases. On the other side, the antioxidant properties of the macrolide were determined in an oxidative stress model with SH-SY5Y cells treated with H2O2. The compound diminished ROS levels and increased cell viability and GSH content by activating the nuclear factor Nrf2. Finally, the neuroprotective ability of the compound was confirmed in two trans-well coculture systems with activated BV2 cells (both with LPS and Aß) and wild type and transfected SH-SY5Y cells. The addition of caniferolide A to microglial cells produced a significant increase in the survival of neuroblastoma in both cases. These results indicate that the compound is able to target many pathological markers of AD, suggesting that caniferolide A could be an interesting drug lead for a polypharmacological approach to the illness.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Inflamação/prevenção & controle , Macrolídeos/farmacologia , Neuroblastoma/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Streptomyces/química , Proteínas tau/metabolismo , Animais , Técnicas In Vitro , Inflamação/metabolismo , Inflamação/patologia , Macrolídeos/química , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
Five new laxaphycins were isolated and fully characterised from the bloom forming cyanobacteria Anabaena torulosa sampled from Moorea, French Polynesia: three acyclic laxaphycin A-type peptides, acyclolaxaphycin A (1), [des-Gly11]acyclolaxaphycin A (2) and [des-(Leu10-Gly11)]acyclolaxaphycin A (3), as well as two cyclic ones, [l-Val8]laxaphycin A (4) and [d-Val9]laxaphycin A (5). The absolute configuration of the amino acids, established using advanced Marfey's analysis for compounds 2-5, highlights a conserved stereochemistry at the Cα carbons of the peptide ring that is characteristic of this family. To the best of our knowledge, this is the first report of acyclic analogues within the laxaphycin A-type peptides. Whether these linear laxaphycins with the aliphatic ß-amino acid on the N-terminal are biosynthetic precursors or compounds obtained after enzymatic hydrolysis of the macrocycle is discussed. Biological evaluation of the new compounds together with the already known laxaphycin A shows that [l-Val8]laxaphycin A, [d-Val9]laxaphycin A and [des-Gly11]acyclolaxaphycin induce cellular toxicity whereas laxaphycin A and des-[(Leu10-Gly11)]acyclolaxaphycin A do not affect the cellular viability. An analysis of cellular death shows that the active peptides do not induce apoptosis or necrosis but instead, involve the autophagy pathway.
Assuntos
Peptídeos Cíclicos/química , Peptídeos/química , Anabaena/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Peptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismoRESUMO
The structures of three new cyclic depsipeptides, tiahuramides A (1), B (2), and C (3), from a French Polynesian collection of the marine cyanobacterium Lyngbya majuscula are described. The planar structures of these compounds were established by a combination of mass spectrometry and 1D and 2D NMR experiments. Absolute configurations of natural and nonproteinogenic amino acids were determined through a combination of acid hydrolysis, derivitization with Marfey's reagent, and HPLC. The absolute configuration of hydroxy acids was confirmed by Mosher's method. The antibacterial activities of tiahuramides against three marine bacteria were evaluated. Compound 3 was the most active compound of the series, with an MIC of 6.7 µM on one of the three tested bacteria. The three peptides inhibit the first cell division of sea urchin fertilized eggs with IC50 values in the range from 3.9 to 11 µM. Tiahuramide B (2), the most potent compound, causes cellular alteration characteristics of apoptotic cells, blebbing, DNA condensation, and fragmentation, already at the first egg cleavage. The cytotoxic activity of compounds 1-3 was tested in SH-SY5Y human neuroblastoma cells. Compounds 2 and 3 showed an IC50 of 14 and 6.0 µM, respectively, whereas compound 1 displayed no toxicity in this cell line at 100 µM. To determine the type of cell death induced by tiahuramide C (3), SH-SY5Y cells were costained with annexin V-FITC and propidium iodide and analyzed by flow cytometry. The double staining indicated that the cytotoxicity of compound 3 in this cell line is produced by necrosis.
Assuntos
Organismos Aquáticos/química , Cianobactérias/química , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Biologia Marinha/métodos , Neuroblastoma/tratamento farmacológicoRESUMO
Makaluvamines are pyrroloiminoquinones isolated from Zyzzya sponges. Until now, they have been described as topoisomerase II inhibitors with cytotoxic effects in diverse tumor cell lines. In the present work, seven makaluvamines were tested in several antioxidant assays in primary cortical neurons and neuroblastoma cells. Among the alkaloids studied, makaluvamine J was the most active in all the assays. This compound was able to reduce the mitochondrial damage elicited by the well-known stressor H2O2. The antioxidant properties of makaluvamine J are related to an improvement of the endogenous antioxidant defenses of glutathione and catalase. SHSY5Y assays proved that this compound acts as a Nrf2 activator leading to an improvement of antioxidant defenses. A low concentration of 10 nM is able to reduce the reactive oxygen species release and maintain a correct mitochondrial function. Based on these results, non-substituted nitrogen in the pyrrole plus the presence of a p-hydroxystyryl without a double bond seems to be the most active structure with a complete antioxidant effect in neuronal cells.
Assuntos
Antioxidantes/farmacologia , Poríferos/química , Pirróis/química , Pirróis/farmacologia , Pirroliminoquinonas/farmacologia , Quinolonas/química , Quinolonas/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Glutationa/metabolismo , Peróxido de Hidrogênio/toxicidade , Camundongos , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-AtividadeRESUMO
Enniatins (ENNs) A1 and B1, previously considered ionophores, are emerging mycotoxins with effects on Ca2+ homeostasis. However, their exact mechanism of action remains unclear. This study investigated how these toxins affect Ca2+ flux in SH-SY5Y cells. ENN A1 induced Ca2+ influx through store-operated channels (SOC). The mitochondrial uncoupler FCCP reduced this influx, suggesting that the mitochondrial status influences the toxin effect. Conversely, ENN B1 did not affect SOC but acted on another Ca2+ channel, as shown when nickel, which directly blocks the Ca2+ channel pore, is added. Mitochondrial function also influenced the effects of ENN B1, as treatment with FCCP reduced toxin-induced Ca2+ depletion and uptake. In addition, both ENNs altered mitochondrial function by producing the opening of the mitochondrial permeability transition pore. This study describes for the first time that ENN A1 and B1 are not Ca2+ ionophores and suggests a different mechanism of action for each toxin.
Assuntos
Cálcio , Depsipeptídeos , Mitocôndrias , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Cálcio/metabolismo , Humanos , Depsipeptídeos/farmacologia , Micotoxinas/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Linhagem Celular TumoralRESUMO
Exploring the chemical diversity present in cyanobacterial mats increasingly frequent in fresh and marine waters is imperative for both evaluating risks associated with these diverse biofilms and their potential for biodiscovery. During a project aimed at the study of the (eco)toxicity of benthic cyanobacteria blooming in some lakes of the West of Ireland, three previously undescribed ahp-cyclodepsipeptides micropeptin LOF941 (1), micropeptin LOF925 (2) and micropeptin LOF953 (3) were isolated from the Microcoleus autumnalis-dominated benthic cyanobacterial biofilm collected from the shore of Lough O'Flynn, Co. Roscommon, Ireland. Their structures remain consistent in their amino acid sequence with the presence of an unusual methionine, and differ by their exocyclic side chains. The planar structures of the previously undescribed micropeptins were elucidated by 1D and 2D NMR and HRESIMS analyses, and their 3D configurations assessed by ROESY NMR and Marfey's analyses. The three isolated compounds showed no cytotoxic effects and all three compounds were shown to exhibit antioxidant properties, with 1 showing the highest bioactivity. Additionally, several micropeptin analogues are proposed from the methanolic fraction of the biofilm extract by UHPLC-HRESIMS/MS analysis and molecular networking. Notably, the known cyanotoxins anatoxin-a and dihydroanatoxin-a were annotated in the molecular network therefore raising issues about the toxicity of this cyanobacterial mat.
Assuntos
Antioxidantes , Cianobactérias , Depsipeptídeos , Cianobactérias/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Irlanda , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Depsipeptídeos/farmacologia , Biofilmes/efeitos dos fármacos , Estrutura Molecular , HumanosRESUMO
Yogurt, a milk-derived product, is susceptible to mycotoxin contamination. While various methods have been developed for the analysis of dairy products, only a few have been specifically validated for yogurt. In addition, these methods are primarily focus on detecting aflatoxins and zearalenone. This study aimed to conduct a preliminary investigation into the presence of regulated, emerging, and modified mycotoxins in natural and oat yogurts available in the Spanish market. For this, a QuEChERS-based extraction method was optimized and then validated to detect and quantify 32 mycotoxins using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The method was in-house validated for the analysis of natural and oat yogurt in terms of linearity, matrix effect, sensitivity, accuracy, and precision. Satisfactory performance characteristics were achieved; for most of the analytes, LOQs were lower than 2 ng/g, and recoveries ranged from 60 to 110% with a precision, expressed as the relative standard deviation of the recovery, lower than 15%. Subsequently, the validated method was applied to analyze commercial yogurt samples, revealing a notable incidence of beauvericin and enniatins, with some analogues found in up to 100% of the samples. Alternariol methyl ether was also frequently found, appearing in 50% of the samples. Additionally, the study identified regulated toxins such as fumonisins, ochratoxin A , and HT-2 toxin. These results provide new incidence data in yogurt, raising concerns about potential health risks for consumers.
RESUMO
Natural toxins, such as mycotoxins and cyanotoxins, can contaminate food and feed, leading to toxicity in humans and animals. This study focused on using nine magnetic nanostructured agents to remove the main types of toxins. Initially, the efficacy of these materials was evaluated in water solutions, revealing that composites with sizes below 3 mm, containing magnetite, activated carbon, esterified pectin, and sodium alginate, removed up to 90% of mycotoxins and cyanotoxins with an adsorption of 873 ng/g. The application of the nanostructures was then assessed in beer, milk, Distillers Dried Grains with Solubles and water contaminated with cyanobacteria. The presence of matrix slightly decreases the adsorption capacity for some toxins. The maximum toxin removal capacity was calculated with cyanotoxins, composites achieved a removal of up to 0.12 mg/g, while nanocomposites (15 µm) reached 36.6 mg/g. Therefore, these findings point out the potential for using nanotechnology in addressing natural toxins contamination.
Assuntos
Contaminação de Alimentos , Micotoxinas , Nanoestruturas , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Micotoxinas/química , Micotoxinas/análise , Adsorção , Nanoestruturas/química , Animais , Cadeia Alimentar , Cerveja/análise , Leite/química , Toxinas Bacterianas/química , Cianobactérias/química , Microcistinas/química , Microcistinas/análiseRESUMO
Manganosalen complexes are a class of catalytic antioxidants with beneficial effects against different neurological disorders according to various in vitro and in vivo studies. The interest in the factors that determine their antioxidant activity is based on the fact that they are key to achieving more efficient models. In this work, we report a set of new manganosalen complexes, thoroughly characterized in the solid state and in solution by different techniques. The chelating Schiff base ligands used were prepared from condensation of different substituted hydroxybenzaldehydes with 1,2-diaminoethane and 1,3-diaminopropane. The antioxidant activity of the new models was tested through superoxide dismutase and catalase probes in conjunction with the studies about their neuroprotective effects in human SH-SY5Y neuroblastoma cells in an oxidative stress model. The ability to scavenge excess reactive oxygen species (ROS) varied depending on the manganosalen models, which also yielded different improvements in cell survival. An assessment of the different factors that affect the oxidant activity for these complexes, and others previously reported, revealed the major influence of the structural factors versus the redox properties of the manganosalen complexes.
RESUMO
Inflammation is the leading subjacent cause of many chronic diseases. Despite several studies in the last decades, the molecular mechanism involving its pathophysiology is not fully known. Recently, the implication of cyclophilins in inflammatory-based diseases has been demonstrated. However, the main role of cyclophilins in these processes remains elusive. Hence, a mouse model of systemic inflammation was used to better understand the relationship between cyclophilins and their tissue distribution. To induce inflammation, mice were fed with high-fat diet for 10 weeks. In these conditions, serum levels of interleukins 2 and 6, tumour necrosis factor-α, interferon-Ï, and the monocyte chemoattractant protein 1 were elevated, evidencing a systemic inflammatory state. Then, in this inflammatory model, cyclophilins and CD147 profiles in the aorta, liver, and kidney were studied. The results demonstrate that, upon inflammatory conditions, cyclophilins A and C expression levels were increased in the aorta. Cyclophilins A and D were augmented in the liver, meanwhile, cyclophilins B and C were diminished. In the kidney, cyclophilins B and C levels were elevated. Furthermore, CD147 receptor was also increased in the aorta, liver, and kidney. In addition, when cyclophilin A was modulated, serum levels of inflammatory mediators were decreased, indicating a reduction in systemic inflammation. Besides, the expression levels of cyclophilin A and CD147 were also reduced in the aorta and liver, when cyclophilin A was modulated. Therefore, these results suggest that each cyclophilin has a different profile depending on the tissue, under inflammatory conditions.
Assuntos
Ciclofilina A , Ciclofilinas , Animais , Camundongos , Ciclofilinas/metabolismo , Ciclofilina A/farmacologia , Inflamação/metabolismoRESUMO
Cyclophilins are a family of chaperones involved in inflammation and cell death. Cyclophilin B is released by inflammatory cells and acts through the receptor CD147, affecting matrix metalloproteases release, whilst cyclophilin D participates in hypoxia-induced apoptosis. Previous studies related hormones like estradiol or prolactin to these proteins, however, their blood concentrations across the menstrual cycle have not been determined. In this work, eleven healthy women (BMI: 21.8 kg/m2) were monitored during a single menstrual cycle, making blood extractions at follicular, periovulatory and mid-luteal phases. Hormone and cyclophilin levels were determined in each phase. Statistical differences were determined by repeated measures ANOVA and estimated marginal means tests, or by Friedman and Dunn-Bonferroni tests for parametric and non-parametric variables, respectively. Bivariate correlations were evaluated with the Spearman coefficient. Cyclophilin B concentrations presented significant differences during the menstrual cycle (p = 0.012). The highest levels of this protein were found at follicular extraction, followed by a decrease at periovulatory phase and a slight increase at mid-luteal phase. Cyclophilin D showed the same profile, although statistical significance was not reached. This immunophilin exhibited a positive correlation with luteinizing hormone at periovulatory phase (r = 0.743, p = 0.009) and with follicle stimulating hormone at mid-luteal phase (r = 0.633, p = 0.036). This is the first study describing the changes in cyclophilin B concentrations across the menstrual cycle, as well as the association of luteinizing and follicle stimulating hormones with cyclophilin D. These results suggest a role of these proteins in the cyclic inflammatory events that affect female reproductive system that should be explored.
Assuntos
Ciclofilinas , Ciclo Menstrual , Feminino , Humanos , Peptidil-Prolil Isomerase F , Hormônio Luteinizante , Hormônio Foliculoestimulante , Estradiol , ProgesteronaRESUMO
Mycotoxins can produce toxic effects on humans; hence, it is of high importance to determine their presence in food products. This work presents a reliable method for the quantification of 32 mycotoxins in cheese. The analysis procedure was optimized based on a QuEChERS extraction process and the ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) detection. The analysis method was validated for four cheese varieties (emmental, blue, brie and camembert) in terms of linearity, sensitivity, matrix effect, accuracy and precision. Satisfactory precision and accuracy values were achieved, with recoveries above 70% for most mycotoxins. The developed method was applied to the analysis of 38 commercial cheese samples. A high occurrence of beauvericin and enniatins were found, ranging from 31% for enniatin A to 100% for enniatin B. The ochratoxin A was detected in three samples at concentrations that may pose a risk to human health.
Assuntos
Queijo , Micotoxinas , Humanos , Micotoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Queijo/análiseRESUMO
Cyclophilins are chaperone proteins that play important roles in signal transduction. Among them, cyclophilins A, B, C, and D were widely associated with inflammation and cardiovascular diseases. Cyclophilins A and C have been proposed as coronary artery disease biomarkers. However, less is known about their relationship with cardiovascular risk factors. Therefore, this study aimed to determine the association between cyclophilin A, B, C, and D and cardiovascular risk factors in coronary artery disease. Serum levels of cyclophilins were measured in 167 subjects (subdivided according to cardiovascular risk factors presence). This study reveals that cyclophilin A and C are elevated in patients regardless of the risk factors presence. Moreover, cyclophilin B is elevated in male patients with hypertension, type 2 diabetes, or high glucose levels. In addition, cyclophilins A, B, and C were significantly correlated with cardiovascular risk factors, but only cyclophilin B was associated with type 2 diabetes. The multivariate analysis strengthens the predictive value for coronary artery disease presence of cyclophilin A (>8.2 ng/mL) and cyclophilin C (>17.5 pg/mL) along with the cardiovascular risk factors tobacco, hypertension, dyslipidemia, and high glucose and cholesterol levels. Moreover, the risk of coronary artery disease is increased in presence of cyclophilin B levels above 63.26 pg/mL and with hypertension or dyslipidemia in male patients. Consequently, cyclophilins A and C serum levels are reinforced as useful coronary artery disease biomarkers, meanwhile, cyclophilin B is a valuable biomarker in the male population when patients are also suffering from hypertension or dyslipidemia.