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1.
Int J Food Microbiol ; 415: 110645, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38430687

RESUMO

This study aimed to assess the growth of Pseudomonas spp. and psychrotrophic bacteria in chilled Pacu (Piaractus mesopotamicus), a native South American fish, stored under chilling conditions (0 to 10 °C) through the use of predictive models under isothermal and non-isothermal conditions. Growth kinetic parameters, maximum growth rate (µmax, 1/h), lag time (tLag, h), and (Nmax, Log10 CFU/g) were estimated using the Baranyi and Roberts microbial growth model. Both kinetic parameters, growth rate and lag time, were significantly influenced by temperature (P < 0.05). The square root secondary model was used to describe the bacteria growth as a function of temperature. Secondary models, √µ = 0.016 (T + 10.13) and √µ =0.017 (T + 9.91) presented a linear correlation with R2 values >0.97 and were further validated under non-isothermal conditions. The model's performance was considered acceptable to predict the growth of Pseudomonas spp. and psychrotrophic bacteria in refrigerated Pacu fillets with bias and accuracy factors between 1.24 and 1.49 (fail-safe) and 1.45-1.49, respectively. Fish biomarkers and spoilage indicators were assessed during storage at 0, 4, and 10 °C. Volatile organic compounds, VOCs (1-hexanol, nonanal, octenol, and indicators 2-ethyl-1-hexanol) showed different behavior with storage time (P > 0.05). 1H NMR analysis confirmed increased enzymatic and microbial activity in Pacu fillets stored at 10 °C compared to 0 °C. The developed and validated models obtained in this study can be used as a tool for decision-making on the shelf-life and quality of refrigerated Pacu fillets stored under dynamic conditions from 0 to 10 °C.


Assuntos
Bactérias , Pseudomonas , Animais , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Prótons por Ressonância Magnética , Temperatura , Microbiologia de Alimentos , Conservação de Alimentos , Contagem de Colônia Microbiana , Armazenamento de Alimentos
2.
Cell Host Microbe ; 32(4): 606-622.e8, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38479396

RESUMO

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes acute, subacute, and chronic human arthritogenic diseases and, in rare instances, can lead to neurological complications and death. Here, we combined epidemiological, virological, histopathological, cytokine, molecular dynamics, metabolomic, proteomic, and genomic analyses to investigate viral and host factors that contribute to chikungunya-associated (CHIK) death. Our results indicate that CHIK deaths are associated with multi-organ infection, central nervous system damage, and elevated serum levels of pro-inflammatory cytokines and chemokines compared with survivors. The histopathologic, metabolite, and proteomic signatures of CHIK deaths reveal hemodynamic disorders and dysregulated immune responses. The CHIKV East-Central-South-African lineage infecting our study population causes both fatal and survival cases. Additionally, CHIKV infection impairs the integrity of the blood-brain barrier, as evidenced by an increase in permeability and altered tight junction protein expression. Overall, our findings improve the understanding of CHIK pathophysiology and the causes of fatal infections.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Febre de Chikungunya/complicações , Proteômica , Vírus Chikungunya/genética , Citocinas/metabolismo
3.
Parkinsonism Relat Disord ; 116: 105847, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37844348

RESUMO

INTRODUCTION: Progressive Supranuclear Palsy (PSP) is a neurodegenerative tauopathy and, to date, the pathophysiological mechanisms in PSP that lead to Tau hyperphosphorylation and neurodegeneration are not clear. In some brain areas, Tau pathology in glial cells appears to precede Tau aggregation in neurons. The development of a model using astrocyte cell lines derived from patients has the potential to identify molecules and pathways that contribute to early events of neurodegeneration. We developed a model of induced pluripotent stem cells (iPSC)-derived astrocytes to investigate the pathophysiology of PSP, particularly early events that might contribute to Tau hyperphosphorylation, applying omics approach to detect differentially expressed genes, metabolites, and proteins, including those from the secretome. METHODS: Skin fibroblasts from PSP patients (without MAPT mutations) and controls were reprogrammed to iPSCs, further differentiated into neuroprogenitor cells (NPCs) and astrocytes. In the 5th passage, astrocytes were harvested for total RNA sequencing. Intracellular and secreted proteins were processed for proteomics experiments. Metabolomics profiling was obtained from supernatants only. RESULTS: We identified hundreds of differentially expressed genes. The main networks were related to cell cycle re-activation in PSP. Several proteins were found exclusively secreted by the PSP group. The cellular processes related to the cell cycle and mitotic proteins, TriC/CCT pathway, and redox signaling were enriched in the secretome of PSP. Moreover, we found distinct sets of metabolites between PSP and controls. CONCLUSION: Our iPSC-derived astrocyte model can provide distinct molecular signatures for PSP patients and it is useful to elucidate the initial stages of PSP pathogenesis.


Assuntos
Células-Tronco Pluripotentes Induzidas , Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Paralisia Supranuclear Progressiva/diagnóstico , Astrócitos/metabolismo , Proteínas tau/genética , Tauopatias/patologia , Neurônios/metabolismo
4.
Metabolites ; 13(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37623846

RESUMO

Cardiovascular disease is a leading cause of death worldwide. Heart failure is a cardiovascular disease with high prevalence, morbidity, and mortality. Several natural compounds have been studied for attenuating pathological cardiac remodeling. Orange juice has been associated with cardiovascular disease prevention by attenuating oxidative stress. However, most studies have evaluated isolated phytochemicals rather than whole orange juice and usually under pathological conditions. In this study, we evaluated plasma metabolomics in healthy rats receiving Pera or Moro orange juice to identify possible metabolic pathways and their effects on the heart. METHODS: Sixty male Wistar rats were allocated into 3 groups: control (C), Pera orange juice (PO), and Moro orange juice (MO). PO and MO groups received Pera orange juice or Moro orange juice, respectively, and C received water with maltodextrin (100 g/L). Echocardiogram and euthanasia were performed after 4 weeks. Plasma metabolomic analysis was performed by high-resolution mass spectrometry. Type I collagen was evaluated in picrosirius red-stained slides and matrix metalloproteinase (MMP)-2 activity by zymography. MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2, TIMP-4, type I collagen, and TNF-α protein expression were evaluated by Western blotting. RESULTS: We differentially identified three metabolites in PO (N-docosahexaenoyl-phenylalanine, diglyceride, and phosphatidylethanolamine) and six in MO (N-formylmaleamic acid, N2-acetyl-L-ornithine, casegravol isovalerate, abscisic alcohol 11-glucoside, cyclic phosphatidic acid, and torvoside C), compared to controls, which are recognized for their possible roles in cardiac remodeling, such as extracellular matrix regulation, inflammation, oxidative stress, and membrane integrity. Cardiac function, collagen level, MMP-2 activity, and MMP-9, TIMP-2, TIMP-4, type I collagen, and TNF-α protein expression did not differ between groups. CONCLUSION: Ingestion of Pera and Moro orange juice induces changes in plasma metabolites related to the regulation of extracellular matrix, inflammation, oxidative stress, and membrane integrity in healthy rats. Moro orange juice induces a larger number of differentially expressed metabolites than Pera orange juice. Alterations in plasma metabolomics induced by both orange juice are not associated with modifications in cardiac extracellular matrix components. Our results allow us to postulate that orange juice may have beneficial effects on pathological cardiac remodeling.

5.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240159

RESUMO

Glioblastoma (GB) is the most aggressive and frequent primary malignant tumor of the central nervous system and is associated with poor overall survival even after treatment. To better understand tumor biochemical alterations and broaden the potential targets of GB, this study aimed to evaluate differential plasma biomarkers between GB patients and healthy individuals using metabolomics analysis. Plasma samples from both groups were analyzed via untargeted metabolomics using direct injection with an electrospray ionization source and an LTQ mass spectrometer. GB biomarkers were selected via Partial Least Squares Discriminant and Fold-Change analyses and were identified using tandem mass spectrometry with in silico fragmentation, consultation of metabolomics databases, and a literature search. Seven GB biomarkers were identified, some of which were unprecedented biomarkers for GB, including arginylproline (m/z 294), 5-hydroxymethyluracil (m/z 143), and N-acylphosphatidylethanolamine (m/z 982). Notably, four other metabolites were identified. The roles of all seven metabolites in epigenetic modulation, energy metabolism, protein catabolism or folding processes, and signaling pathways that activate cell proliferation and invasion were elucidated. Overall, the findings of this study highlight new molecular targets to guide future investigations on GB. These molecular targets can also be further evaluated to derive their potential as biomedical analytical tools for peripheral blood samples.


Assuntos
Glioblastoma , Humanos , Metabolômica/métodos , Biomarcadores , Espectrometria de Massas em Tandem/métodos , Análise dos Mínimos Quadrados
6.
Am J Physiol Endocrinol Metab ; 324(3): E226-E240, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724126

RESUMO

Obesity is one of the leading noncommunicable diseases in the world. Despite intense efforts to develop strategies to prevent and treat obesity, its prevalence continues to rise worldwide. A recent study has shown that the tricarboxylic acid intermediate succinate increases body energy expenditure by promoting brown adipose tissue thermogenesis through the activation of uncoupling protein-1; this has generated interest surrounding its potential usefulness as an approach to treat obesity. It is currently unknown how succinate impacts brown adipose tissue protein expression, and how exogenous succinate impacts body mass reduction promoted by a drug approved to treat human obesity, the glucagon-like-1 receptor agonist, liraglutide. In the first part of this study, we used bottom-up shotgun proteomics to determine the acute impact of exogenous succinate on the brown adipose tissue. We show that succinate rapidly affects the expression of 177 brown adipose tissue proteins, which are mostly associated with mitochondrial structure and function. In the second part of this study, we performed a short-term preclinical pharmacological intervention, treating diet-induced obese mice with a combination of exogenous succinate and liraglutide. We show that the combination was more efficient than liraglutide alone in promoting body mass reduction, food energy efficiency reduction, food intake reduction, and an increase in body temperature. Using serum metabolomics analysis, we showed that succinate, but not liraglutide, promoted a significant increase in the blood levels of several medium and long-chain fatty acids. In conclusion, exogenous succinate promotes rapid changes in brown adipose tissue mitochondrial proteins, and when used in association with liraglutide, increases body mass reduction.NEW & NOTEWORTHY Exogenous succinate induces major changes in brown adipose tissue protein expression affecting particularly mitochondrial respiration and structural proteins. When given exogenously in drinking water, succinate mitigates body mass gain in a rodent model of diet-induced obesity; in addition, when given in association with the glucagon-like peptide-1 receptor agonist, liraglutide, succinate increases body mass reduction promoted by liraglutide alone.


Assuntos
Tecido Adiposo Marrom , Liraglutida , Animais , Camundongos , Tecido Adiposo Marrom/metabolismo , Metabolismo Energético , Liraglutida/farmacologia , Liraglutida/uso terapêutico , Obesidade/metabolismo , Proteoma/metabolismo , Ácido Succínico/farmacologia , Ácido Succínico/metabolismo , Ácido Succínico/uso terapêutico , Termogênese , Proteína Desacopladora 1/metabolismo
7.
J Proteome Res ; 22(1): 193-203, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36469742

RESUMO

The outbreak of Zika virus infection in 2016 led to the identification of its presence in several types of biofluids, including semen. Later discoveries associated Zika infection with sexual transmission and persistent replication in cells of the male reproductive tract. Prostate epithelial and carcinoma cells are favorable to virus replication, with studies pointing to transcriptomics alterations of immune and inflammation genes upon persistence. However, metabolome alterations promoted by the Zika virus in prostate cells are unknown. Given its chronic effects and oncolytic potential, we aim to investigate the metabolic alterations induced by the Zika virus in prostate epithelial (PNT1a) and adenocarcinoma (PC-3) cells using an untargeted metabolomics approach and high-resolution mass spectrometry. PNT1a cells were viable up to 15 days post ZIKV infection, in contrast to its antiproliferative effect in the PC-3 cell lineage. Remarkable alterations in the PNT1a cell metabolism were observed upon infection, especially regarding glycerolipids, fatty acids, and acylcarnitines, which could be related to viral cellular resource exploitation, in addition to the over-time increase in oxidative stress metabolites associated with carcinogenesis. The upregulation of FA20:5 at 5 dpi in PC-3 cells corroborates the antiproliferative effect observed since this metabolite was previously reported to induce PC-3 cell death. Overall, Zika virus promotes extensive lipid alterations on both PNT1a and PC-3 cells, promoting different outcomes based on the cellular metabolic state.


Assuntos
Adenocarcinoma , Infecção por Zika virus , Zika virus , Masculino , Humanos , Próstata , Células PC-3
8.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613836

RESUMO

Meningiomas (MGMs) are currently classified into grades I, II, and III. High-grade tumors are correlated with decreased survival rates and increased recurrence rates. The current grading classification is based on histological criteria and determined only after surgical tumor sampling. This study aimed to identify plasma metabolic alterations in meningiomas of different grades, which would aid surgeons in predefining the ideal surgical strategy. Plasma samples were collected from 51 patients with meningioma and classified into low-grade (LG) (grade I; n = 43), and high-grade (HG) samples (grade II, n = 5; grade III, n = 3). An untargeted metabolomic approach was used to analyze plasma metabolites. Statistical analyses were performed to select differential biomarkers among HG and LG groups. Metabolites were identified using tandem mass spectrometry along with database verification. Five and four differential biomarkers were identified for HG and LG meningiomas, respectively. To evaluate the potential of HG MGM metabolites to differentiate between HG and LG tumors, a receiving operating characteristic curve was constructed, which revealed an area under the curve of 95.7%. This indicates that the five HG MGM metabolites represent metabolic alterations that can differentiate between LG and HG meningiomas. These metabolites may indicate tumor grade even before the appearance of histological features.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patologia , Neoplasias Meníngeas/patologia , Gradação de Tumores , Estudos Retrospectivos
9.
J Photochem Photobiol B ; 223: 112297, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482154

RESUMO

Lipid oxidation is ubiquitous in cell life under oxygen and essential for photodynamic therapy (PDT) of carcinomas. However, the mechanisms underlying lipid oxidation in rather complex systems such as plasma membranes remain elusive. Herein, Langmuir monolayers were assembled with the lipid extract of glandular breast cancer (MCF7) cells and used to probe the molecular interactions allowing adsorption of the photosensitizer (PS) erythrosine B and subsequent photooxidation outcomes. Surface pressure (π) versus area (cm2/mL) isotherms of MCF7 lipid extract shifted to larger areas upon erythrosine incorporation, driven by secondary interactions that affected the orientation of the carbonyl groups and lipid chain organization. Light-irradiation increased the surface area of the MCF7 lipid extract monolayer containing erythrosine owing to the lipid hydroperoxidation, which may further undergo decomposition, resulting in the chain cleavage of phospholipids and membrane permeabilization. Incorporation of erythrosine by MCF7 cells induced slight toxic effects on in vitro assays, differently of the severe phototoxicity caused by light-irradiation, which significantly decreased cell viability by more than 75% at 2.5 × 10-6 mol/L of erythrosine incubated for 3 and 24 h, reaching nearly 90% at 48 h of incubation. The origin of the phototoxic effects is in the rupture of the plasma membrane shown by the frontal (FSC) and side (SSC) light scattering of flow cytometry. Consistent with hydroperoxide decomposition, membrane permeabilization was also confirmed by cleaved lipids detected in mass spectrometry and subsidizes the necrotic pathway of cell death.


Assuntos
Membrana Celular/efeitos dos fármacos , Eritrosina/farmacologia , Luz , Fármacos Fotossensibilizantes/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Elasticidade , Eritrosina/química , Feminino , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Lipídeos/análise , Lipídeos/química , Microscopia Confocal , Fármacos Fotossensibilizantes/química , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray
10.
Sci Rep ; 9(1): 13606, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31541139

RESUMO

Zika virus (ZIKV) has emerged as one of the most medically relevant viral infections of the past decades; the devastating effects of this virus over the developing brain are a major matter of concern during pregnancy. Although the connection with congenital malformations are well documented, the mechanisms by which ZIKV reach the central nervous system (CNS) and the causes of impaired cortical growth in affected fetuses need to be better addressed. We performed a non-invasive, metabolomics-based screening of saliva from infants with congenital Zika syndrome (CZS), born from mothers that were infected with ZIKV during pregnancy. We were able to identify three biomarkers that suggest that this population suffered from an important inflammatory process; with the detection of mediators associated with glial activation, we propose that microcephaly is a product of immune response to the virus, as well as excitotoxicity mechanisms, which remain ongoing even after birth.


Assuntos
Microcefalia/etiologia , Saliva/química , Infecção por Zika virus/diagnóstico , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Biomarcadores , Feminino , Desenvolvimento Fetal , Feto , Humanos , Lactente , Recém-Nascido , Inflamação/complicações , Estudos Longitudinais , Masculino , Metabolômica/métodos , Microcefalia/virologia , Mães , Parto , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Viroses , Zika virus/patogenicidade , Infecção por Zika virus/virologia
11.
Food Chem Toxicol ; 133: 110756, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31408721

RESUMO

Yeasts are able to reduce the levels of ochratoxin A in fermentative processes; and, through their enzymatic complex, these micro-organisms are also capable of forming modified mycotoxins. These mycotoxins are often underreported, and may increase health risks after ingestion of contaminated food. In this sense, this study aims to evaluate whether the presence of ochratoxin A influences yeast growth kinetic parameters and to elucidate the formation of modified ochratoxin by Saccharomyces cerevisiae strains during fermentation. Three S. cerevisiae strains (12 M, 01 PP, 41 PP) were exposed to OTA at the concentrations of 10, 20 and 30 µg/L. The Baranyi model was fitted to the growth data (Log CFU/mL), and the identification of modified ochratoxins was performed through High Resolution Mass Spectrometry. The presence of ochratoxin A did not influence the growth of S. cerevisiae strains. Four pathways were proposed for the metabolization of OTA: dechlorination, hydrolysis, hydroxylation, and conjugation. Among the elected targets, the following were identified: ochratoxin α, ochratoxin ß, ochratoxin α methyl ester, ochratoxin B methyl ester, ethylamide ochratoxin A, ochratoxin C, hydroxy-ochratoxin A, hydroxy-ochratoxin A methyl ester, and ochratoxin A cellobiose ester. These derivatives formed from yeast metabolism may contribute to the occurrence of underreporting levels of total mycotoxin in fermented products.


Assuntos
Ocratoxinas/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Cinética , Modelos Biológicos , Ocratoxinas/análise
12.
Sci Rep ; 9(1): 6803, 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31028284

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

13.
Sci Rep ; 8(1): 14573, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30275502

RESUMO

Aspergillus carbonarius and Aspergillus niger are the main responsible fungi for the accumulation of ochratoxin A (OTA) in wine grapes. Some strains are able to convert the parent mycotoxin into other compounds by means of hydrolysis and/or conjugation reactions through their defense mechanisms and enzymatic activity, leading to the formation of a modified mycotoxin. Thus, the variability of growth and metabolite production are inherent to the strain, occurring distinctively even when submitted to similar conditions. In this sense, this contribution aimed at determining the variability in multiplication and production of OTA by strains of A. carbonarius and A. niger isolated from grapes, as well as investigating the formation of modified mycotoxins. Strains were incubated in grape-based medium, and the diameter of the colonies measured daily. The determination of OTA was performed by high-performance liquid chromatography and the identification of modified mycotoxins was carried out using high-resolution mass spectrometry. Variabilities in terms of growth and OTA production were assessed across five different strains. Peak production of OTA was detected on day 15, and a decline on day 21 was observed, indicating that the observed reduction may be associated with the degradation or modification of the OTA over time by the fungus. Ethylamide ochratoxin A, a modified mycotoxin identified in this study, provides evidence that there may be underreporting of total mycotoxin levels in food, increasing uncertainty concerning health risks to the population.


Assuntos
Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Meios de Cultura/química , Ocratoxinas/metabolismo , Aspergillus/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Técnicas Microbiológicas , Fatores de Tempo , Vitis/microbiologia
14.
J Agric Food Chem ; 66(33): 8824-8831, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30048130

RESUMO

Ochratoxin A is the main contaminant mycotoxin of grapes produced mainly by Aspergillus niger and Aspergillus carbonarius. Besides, it is possible that the formation of modified mycotoxin occurs through the plant defense mechanism or also by fungus actions itself. The objective of this study was to evaluate the influence of grape variety and maturation stage on the formation of OTA and modified mycotoxin. The determination of OTA was performed by high-performance liquid chromatography, and a high-resolution mass spectrometry was used for the detection of modified ochratoxin. A positive correlation was observed between the following grapes physicochemical parameters: pH, total soluble solids, total glycosides in glucose, total anthocyanin, and OTA levels produced by A. niger and A. carbonarius. Therefore, the higher the concentrations of these parameters, the greater the production of mycotoxin in grapes. Among the elected targets, we identified the 14-decarboxy-ochratoxin A in Muscat Italia variety at veraison and 15 days after the beginning of veraison stages; and ethylamide-ochratoxin A as a biomarker in the Syrah variety at the ripeness stage.


Assuntos
Aspergillus niger/metabolismo , Aspergillus/metabolismo , Frutas/química , Ocratoxinas/análise , Vitis/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Frutas/classificação , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Espectrometria de Massas , Ocratoxinas/metabolismo , Vitis/química , Vitis/classificação , Vitis/microbiologia , Vinho/análise
15.
Front Pharmacol ; 9: 685, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29997512

RESUMO

Statins are the preferred therapy to treat hypercholesterolemia. Their main action consists of inhibiting the cholesterol biosynthesis pathway. Previous studies report mitochondrial oxidative stress and membrane permeability transition (MPT) of several experimental models submitted to diverse statins treatments. The aim of the present study was to investigate whether chronic treatment with the hydrophilic pravastatin induces hepatotoxicity in LDL receptor knockout mice (LDLr-/-), a model for human familial hypercholesterolemia. We evaluated respiration and reactive oxygen production rates, cyclosporine-A sensitive mitochondrial calcium release, antioxidant enzyme activities in liver mitochondria or homogenates obtained from LDLr-/- mice treated with pravastatin for 3 months. We observed that pravastatin induced higher H2O2 production rate (40%), decreased activity of aconitase (28%), a superoxide-sensitive Krebs cycle enzyme, and increased susceptibility to Ca2+-induced MPT (32%) in liver mitochondria. Among several antioxidant enzymes, only glucose-6-phosphate dehydrogenase (G6PD) activity was increased (44%) in the liver of treated mice. Reduced glutathione content and reduced to oxidized glutathione ratio were increased in livers of pravastatin treated mice (1.5- and 2-fold, respectively). The presence of oxidized lipid species were detected in pravastatin group but protein oxidation markers (carbonyl and SH- groups) were not altered. Diet supplementation with the antioxidants CoQ10 or creatine fully reversed all pravastatin effects (reduced H2O2 generation, susceptibility to MPT and normalized aconitase and G6PD activity). Taken together, these results suggest that 1- pravastatin induces liver mitochondrial redox imbalance that may explain the hepatic side effects reported in a small number of patients, and 2- the co-treatment with safe antioxidants neutralize these side effects.

16.
Pharmacol Res ; 132: 33-46, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29653264

RESUMO

Intestinal helminths are prevalent in individuals who live in rural areas of developing countries, where obesity, type 2 diabetes, and metabolic syndrome are rare. In the present study, we analyzed the modulation of the gut microbiota in mice infected with the helminth Strongyloides venezuelensis, and fed either a standard rodent chow diet or high-fat diet (HFD). To investigate the effects of the microbiota modulation on the metabolism, we analyzed the expression of tight-junction proteins present in the gut epithelium, inflammatory markers in the serum and tissue and quantified glucose tolerance and insulin sensitivity and resistance. Additionally, the levels of lipids related to inflammation were evaluated in the feces and serum. Our results show that infection with Strongyloides venezuelensis results in a modification of the gut microbiota, most notably by increasing Lactobacillus spp. These modifications in the microbiota alter the host metabolism by increasing the levels of anti-inflammatory cytokines, switching macrophages from a M1 to M2 pattern in the adipose tissue, increasing the expression of tight junction proteins in the intestinal cells (thereby reducing the permeability) and decreasing LPS in the serum. Taken together, these changes correlate with improved insulin signaling and sensitivity, which could also be achieved with HFD mice treated with probiotics. Additionally, helminth infected mice produce higher levels of oleic acid, which participates in anti-inflammatory pathways. These results suggest that modulation of the microbiota by helminth infection or probiotic treatment causes a reduction in subclinical inflammation, which has a positive effect on the glucose metabolism of the host.


Assuntos
Ácidos Graxos/metabolismo , Microbioma Gastrointestinal , Resistência à Insulina , Estrongiloidíase/metabolismo , Estrongiloidíase/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Microbioma Gastrointestinal/genética , Masculino , Camundongos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Strongyloides
17.
Food Res Int ; 103: 8-11, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389646

RESUMO

Chocolate is a popular food bearing a number of different classifications that are differentiated by proportions of cocoa solids, milk and cocoa butter. Literature brings evidence that chocolates with a high percentage of cocoa solids contribute to good health maintenance due to the presence of phenolic compounds. On the other hand, it is known that the productive process, including pre-processing, may influence the level of these substances in the finished product. Thus, accurate strategies to measure the levels of this class of molecules that can be highly adaptable throughout the manufacturing process are important to ensure high-quality products. Mass spectrometry is an analytical tool of high sensitivity and specificity that is leading the research in food analysis towards new directions. By using mass spectrometry imaging in direct food analysis, this contribution developed an effective methodology for comparatively establishing the levels of catechin/epicatechin as phenolics content markers for cocoa content in a series of commercial chocolates from a single manufacturer, rendering a versatile tool that can be applied in fast screening of cocoa content in finished products and during manufacturing.


Assuntos
Chocolate/análise , Análise de Alimentos/métodos , Fenóis/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Reprodutibilidade dos Testes , Fatores de Tempo , Fluxo de Trabalho
19.
20.
Front Microbiol ; 8: 1954, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29067015

RESUMO

Zika virus (ZIKV) infection has recently emerged as a major concern worldwide due to its strong association with nervous system malformation (microcephaly) of fetuses in pregnant women infected by the virus. Signs and symptoms of ZIKV infection are often mistaken with other common viral infections. Since transmission may occur through biological fluids exchange and coitus, in addition to mosquito bite, this condition is an important infectious disease. Thus, understanding the mechanism of viral infection has become an important research focus, as well as providing potential targets for assertive clinical diagnosis and quality screening for hemoderivatives. Within this context, the present work analyzed blood plasma from 79 subjects, divided as a control group and a ZIKV-infected group. Samples underwent direct-infusion mass spectrometry and statistical analysis, where eight markers related to the pathophysiological process of ZIKV infection were elected and characterized. Among these, Angiotensin (1-7) and Angiotensin I were upregulated under infection, showing an attempt to induce autophagy of the infected cells. However, this finding is concerning about hypertensive individuals under treatment with inhibitors of the Renin-Angiotensin System (RAS), which could reduce this response against the virus and exacerbate the symptoms of the infection. Moreover, one of the most abundant glycosphingolipids in the nervous tissue, Ganglioside GM2, was also elected in the present study as an infection biomarker. Considered an important pathogen receptor at membrane's outer layer, this finding represents the importance of gangliosides for ZIKV infection and its association with brain tropism. Furthermore, a series of phosphatidylinositols were also identified as biomarkers, implying a significant role of the PI3K-AKT-mTOR Pathway in this mechanism. Finally, these pathways may also be understood as potential targets to be considered in pharmacological intervention studies on ZIKV infection management.

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