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BACKGROUND: Older subjects are at risk of elevated intestinal permeability (IP) which can lead to immune system activation and low-grade systemic inflammation. Dietary changes are a potential strategy to reduce IP. The MaPLE project evaluated the hypothesis that increasing (poly)phenol intake would beneficially impact on several important markers and pathways related to IP. The objective of the present study was to assess the effects of the MaPLE (poly)phenol-rich diet (PR-diet) on additional IP-related biomarkers and any relationships between biomarker responses. METHODS: A randomised, controlled, crossover study was performed involving 51 participants (≥ 60 y) with increased IP, as determined by serum zonulin levels. Participants were randomly assigned to one of two intervention groups: a control diet (C-diet) or a PR-diet. Each intervention lasted 8 weeks and was separated by an 8-week washout period. For the present study, serum and faecal samples were used to measure zonula occludens-1 (ZO-1), occludin, adiponectin, calprotectin, faecal calprotectin, soluble cluster of differentiation 14 (sCD14), interleukin-6 receptor (IL-6R), and vascular endothelial-cadherin (VEC) levels using quantitative ELISA assays. Data were analysed using ANOVA, and Spearman and network correlation analysis were performed to identify the relationship among biomarkers at baseline. RESULTS: Among the different markers analysed, a significant reduction was observed for faecal and serum calprotectin (p = 0.0378 and p = 0.0186, respectively) following the PR-diet, while a significant increase in ZO-1 was found (p = 0.001) after both the intervention periods (PR-diet and C-diet). In addition, a time effect was observed for VEC levels showing a reduction (p = 0.038) following the PR-diet. Based on network correlation analysis, two clusters of correlations were identified: one cluster with high levels of serum calprotectin, faecal calprotectin, sCD14, interleukin (IL)-6, tumor necrosis factor (TNF)-α, C-reactive protein (CRP) and bacterial DNAemia (16 S rRNA gene copies), with potential inflammatory-induced intestinal permeability. Differently, the other cluster had high levels of serum occludin, IL-6R, soluble intercellular adhesion molecule-1 (sICAM-1) and VEC, with potential inflammatory-induced endothelial dysfunction. CONCLUSIONS: Overall, this study provides further support to the hypothesis that a (poly)phenol-rich diet may help to ameliorate intestinal permeability-associated conditions. In this regard, calprotectin might represent a promising biomarker since it is a protein that typically increases with age and it is considered indicative of intestinal and systemic inflammation. Further research is needed to develop targeted (poly)phenol-rich diets against age-related gut dysfunction and inflammation. TRIAL REGISTRATION: 28/04/2017; ISRCTN10214981; https://doi.org/10.1186/ISRCTN10214981 .
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Estudos Cross-Over , Fezes , Complexo Antígeno L1 Leucocitário , Permeabilidade , Polifenóis , Humanos , Masculino , Feminino , Idoso , Complexo Antígeno L1 Leucocitário/análise , Complexo Antígeno L1 Leucocitário/sangue , Fezes/química , Polifenóis/farmacologia , Polifenóis/administração & dosagem , Pessoa de Meia-Idade , Biomarcadores/sangue , Mucosa Intestinal/metabolismo , Dieta/métodos , Idoso de 80 Anos ou mais , Função da Barreira IntestinalRESUMO
The study aims to evaluate the effect of an acute meal and long-term intake of Mediterranean Diet (MD) on different parameters such as strength, physical performance, body composition and blood markers in a group of non-professional athletes who practice a strength activity. Thirteen volunteers completed two 8-week dietary interventions in a randomised, cross-over design. Also an acute study was performed. Subjects received a MD High in carbohydrates, characterised by at least five portions of pasta/week and an average 55-60% of daily energy derived from carbohydrates, versus an MD reduced in carbohydrates, with less than two portions of pasta/week and an average of 40-45% of daily energy provided by carbohydrates. Mainly, data did not show significant differences for the parameters analysed, except for Elbow Flexor maximum voluntary contraction (p = .039). Results enlighten that increasing total carbohydrates intake, as typically in the MD, does not negatively affect physical performance, body composition and strength.
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Atletas , Biomarcadores , Composição Corporal , Estudos Cross-Over , Dieta Mediterrânea , Carboidratos da Dieta , Refeições , Humanos , Masculino , Carboidratos da Dieta/administração & dosagem , Adulto , Biomarcadores/sangue , Adulto Jovem , Feminino , Força Muscular , Desempenho Atlético/fisiologia , Ingestão de EnergiaRESUMO
The comet assay is widely used in biomonitoring studies for the analysis of DNA damage in leukocytes and peripheral blood mononuclear cells. Rather than processing blood samples directly, it can be desirable to cryopreserve whole blood or isolated cells for later analysis by the comet assay. However, this creates concern about artificial accumulation of DNA damage during cryopreservation. In this study, 10 laboratories used standardized cryopreservation and thawing procedures of monocytic (THP-1) or lymphocytic (TK6) cells. Samples were cryopreserved in small aliquots in 50% foetal bovine serum, 40% cell culture medium, and 10% dimethyl sulphoxide. Subsequently, cryopreserved samples were analysed by the standard comet assay on three occasions over a 3-year period. Levels of DNA strand breaks in THP-1 cells were increased (four laboratories), unaltered (four laboratories), or decreased (two laboratories) by long-term storage. Pooled analysis indicates only a modest positive association between storage time and levels of DNA strand breaks in THP-1 cells (0.37% Tail DNA per year, 95% confidence interval: -0.05, 0.78). In contrast, DNA strand break levels were not increased by cryopreservation in TK6 cells. There was inter-laboratory variation in levels of DNA strand breaks in THP-1 cells (SD = 3.7% Tail DNA) and TK6 reference sample cells (SD = 9.4% Tail DNA), whereas the intra-laboratory residual variation was substantially smaller (i.e. SD = 0.4%-2.2% Tail DNA in laboratories with the smallest and largest variation). In conclusion, the study shows that accumulation of DNA strand breaks in cryopreserved mononuclear blood cell lines is not a matter of concern.
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Dano ao DNA , Leucócitos Mononucleares , Ensaio Cometa/métodos , Leucócitos Mononucleares/metabolismo , Criopreservação/métodos , DNA/metabolismoRESUMO
The formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay is widely used for the measurement of oxidatively generated damage to DNA. However, there has not been a recommended long-term positive control for this version of the comet assay. We have investigated potassium bromate as a positive control for the Fpg-modified comet assay because it generates many Fpg-sensitive sites with a little concurrent generation of DNA strand breaks. Eight laboratories used the same procedure for the treatment of monocytic THP-1 cells with potassium bromate (0, 0.5, 1.5, and 4.5 mM) and subsequent cryopreservation in a freezing medium consisting of 50% foetal bovine serum, 40% RPMI-1640 medium, and 10% dimethyl sulphoxide. The samples were analysed by the Fpg-modified comet assay three times over a 3-year period. All laboratories obtained a positive concentration-response relationship in cryopreserved samples (linear regression coefficients ranging from 0.79 to 0.99). However, there was a wide difference in the levels of Fpg-sensitive sites between the laboratory with the lowest (4.2% Tail DNA) and highest (74% Tail DNA) values in THP-1 cells after exposure to 4.5 mM KBrO3. In an attempt to assess sources of inter-laboratory variation in Fpg-sensitive sites, comet images from one experiment in each laboratory were forwarded to a central laboratory for visual scoring. There was high consistency between measurements of %Tail DNA values in each laboratory and the visual score of the same comets done in the central laboratory (r = 0.98, P < 0.001, linear regression). In conclusion, the results show that potassium bromate is a suitable positive comet assay control.
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Measurement of DNA migration in the comet assay can be done by image analysis or visual scoring. The latter accounts for 20%-25% of the published comet assay results. Here we assess the intra- and inter-investigator variability in visual scoring of comets. We include three training sets of comet images, which can be used as reference for researchers who wish to use visual scoring of comets. Investigators in 11 different laboratories scored the comet images using a five-class scoring system. There is inter-investigator variation in the three training sets of comets (i.e. coefficient of variation (CV) = 9.7%, 19.8%, and 15.2% in training sets I-III, respectively). However, there is also a positive correlation of inter-investigator scoring in the three training sets (r = 0.60). Overall, 36% of the variation is attributed to inter-investigator variation and 64% stems from intra-investigator variation in scoring between comets (i.e. the comets in training sets I-III look slightly different and this gives rise to heterogeneity in scoring). Intra-investigator variation in scoring was also assessed by repeated analysis of the training sets by the same investigator. There was larger variation when the training sets were scored over a period of six months (CV = 5.9%-9.6%) as compared to 1 week (CV = 1.3%-6.1%). A subsequent study revealed a high inter-investigator variation when premade slides, prepared in a central laboratory, were stained and scored by investigators in different laboratories (CV = 105% and 18%-20% in premade slides with comets from unexposed and hydrogen peroxide-exposed cells, respectively). The results indicate that further standardization of visual scoring is desirable. Nevertheless, the analysis demonstrates that visual scoring is a reliable way of analysing DNA migration in comets.
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The comet assay is a simple and versatile method for measurement of DNA damage in eukaryotic cells. More specifically, the assay detects DNA migration from agarose gel-embedded nucleoids, which depends on assay conditions and the level of DNA damage. Certain steps in the comet assay procedure have substantial impact on the magnitude of DNA migration (e.g. electric potential and time of electrophoresis). Inter-laboratory variation in DNA migration levels occurs because there is no agreement on optimal assay conditions or suitable assay controls. The purpose of the hCOMET ring trial was to test potassium bromate (KBrO3) as a positive control for the formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay. To this end, participating laboratories used semi-standardized protocols for cell culture (i.e. cell culture, KBrO3 exposure, and cryopreservation of cells) and comet assay procedures, whereas the data acquisition was not standardized (i.e. staining of comets and image analysis). Segregation of the total variation into partial standard deviation (SD) in % Tail DNA units indicates the importance of cell culture procedures (SD = 10.9), comet assay procedures (SD = 12.3), staining (SD = 7.9) and image analysis (SD = 0.5) on the overall inter-laboratory variation of DNA migration (SD = 18.2). Future studies should assess sources of variation in each of these steps. On the positive side, the hCOMET ring trial demonstrates that KBrO3 is a robust positive control for the Fpg-modified comet assay. In conclusion, the hCOMET ring trial has demonstrated a high reproducibility of detecting genotoxic effects by the comet assay, but inter-laboratory variation of DNA migration levels is a concern.
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PURPOSE: Chlorogenic acid (CGA) and caffeic acid (CA) are bioactive compounds in whole grains, berries, apples, some citrus fruits and coffee, which are hypothesized to promote health-beneficial effects on the cardiovascular system. This study aimed to evaluate the capacity of CGA and CA to reduce lipid accumulation in macrophages, recognized as a critical stage in the progression of atherosclerosis. Furtherly, the modulation of CCAAT/enhancer-binding protein ß (C/EBPß) and peroxisome proliferator-activated receptor- γ1 (PPAR-γ1), as transcription factors involved in lipid metabolism, was evaluated. METHODS: THP-1-derived macrophages were treated for 24 h with 0.03, 0.3, 3 and 30 µM of CGA and CA, tested alone or in combination, and a solution of oleic/palmitic acid (500 µM, 2:1 ratio). Lipid storage was assessed spectrophotometrically through fluorescent staining of cells with Nile red. C/EBPß and PPAR-γ1 mRNA and protein levels were evaluated by RT-PCR and enzyme-linked immunosorbent assay, respectively. RESULTS: The mix of CGA + CA (1:1 ratio) reduced lipid accumulation at all concentrations tested, except for the highest one. The greatest effect ( - 65%; p < 0.01) was observed at the concentration of 0.3 µM for each compound. The same concentration significantly (p < 0.01) downregulated C/EBPß and PPAR-γ1 gene expression and reduced their protein levels at 2 h and 24 h, respectively. CONCLUSION: The results indicate that the capacity of CGA + CA mix to reduce lipid storage in macrophages is mediated by a reduction in the expression of transcription factors C/EBPß and PPAR-γ1.
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Promoção da Saúde , PPAR gama , Ácidos Cafeicos , Ácido Clorogênico/farmacologia , Metabolismo dos Lipídeos , Lipídeos , Macrófagos/metabolismo , PPAR gama/genética , PPAR gama/metabolismoRESUMO
PURPOSE: Aging can be characterized by increased systemic low-grade inflammation, altered gut microbiota composition, and increased intestinal permeability (IP). The intake of polyphenol-rich foods is proposed as a promising strategy to positively affect the gut microbiota-immune system-intestinal barrier (IB) axis. In this context, we tested the hypothesis that a PR-dietary intervention would affect the presence of bacterial factors in the bloodstream of older adults. METHODS: We collected blood samples within a randomized, controlled, crossover intervention trial in which older volunteers (n = 51) received a polyphenol-enriched and a control diet. We quantified the presence of bacterial DNA in blood by qPCR targeting the 16S rRNA gene (16S; bacterial DNAemia). Blood DNA was taxonomically profiled via 16S sequencing. RESULTS: Higher blood 16S levels were associated with higher BMI and markers of IP, inflammation, and dyslipidemia. PR-intervention did not significantly change bacterial DNAemia in the older population (P = 0.103). Nonetheless, the beneficial changes caused by the polyphenol-enriched diet were greatest in participants with higher bacterial DNAemia, specifically in markers related to IP, inflammation and dyslipidemia, and in fecal bacterial taxa. Finally, we found that the bacterial DNA detected in blood mostly belonged to γ-Proteobacteria, whose abundance significantly decreased after the polyphenol-rich diet in subjects with higher bacterial DNAemia at baseline. CONCLUSIONS: This study shows that older subjects with higher bacterial DNAemia experienced a beneficial effect from a polyphenol-rich diet. Bacterial DNAemia may be a further relevant marker for the identification of target populations that could benefit more from a protective dietary treatment. REGISTRATION: This trial was retrospectively registered at www.isrctn.org (ISRCTN10214981) on April 28, 2017.
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Doenças Cardiovasculares , Polifenóis , Idoso , Biomarcadores , Doenças Cardiovasculares/prevenção & controle , Dieta , Fezes/microbiologia , Fatores de Risco de Doenças Cardíacas , Humanos , Permeabilidade , Polifenóis/farmacologia , RNA Ribossômico 16S/genética , Fatores de RiscoRESUMO
DNA damage and repair activity are often assessed in blood samples from humans in different types of molecular epidemiology studies. However, it is not always feasible to analyse the samples on the day of collection without any type of storage. For instance, certain studies use repeated sampling of cells from the same subject or samples from different subjects collected at different time-points, and it is desirable to analyse all these samples in the same comet assay experiment. In addition, flawless comet assay analyses on frozen samples open up the possibility of using this technique on biobank material. In this article we discuss the use of cryopreserved peripheral blood mononuclear cells (PBMCs), buffy coat (BC) and whole blood (WB) for analysis of DNA damage and repair using the comet assay. The published literature and the authors' experiences indicate that various types of blood samples can be cryopreserved with only a minor effect on the basal level of DNA damage. There is evidence to suggest that WB and PBMCs can be cryopreserved for several years without much effect on the level of DNA damage. However, care should be taken when cryopreserving WB and BCs. It is possible to use either fresh or frozen samples of blood cells, but results from fresh and frozen cells should not be used in the same dataset. The article outlines detailed protocols for the cryopreservation of PBMCs, BCs and WB samples.
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Preservação de Sangue , Ensaio Cometa , Dano ao DNA , Reparo do DNA , Leucócitos Mononucleares , Coleta de Amostras Sanguíneas , Criopreservação , HumanosRESUMO
The comet assay is a popular assay in biomonitoring studies. DNA strand breaks (or unspecific DNA lesions) are measured using the standard comet assay. Oxidative stress-generated DNA lesions can be measured by employing DNA repair enzymes to recognise oxidatively damaged DNA. Unfortunately, there has been a tendency to fail to report results from assay controls (or maybe even not to employ assay controls). We believe this might have been due to uncertainty as to what really constitutes a positive control. It should go without saying that a biomonitoring study cannot have a positive control group as it is unethical to expose healthy humans to DNA damaging (and thus potentially carcinogenic) agents. However, it is possible to include assay controls in the analysis (here meant as a cryopreserved sample of cells i.e. included in each experiment as a reference sample). In the present report we tested potassium bromate (KBrO3) as a positive comet assay control for the formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay. Ten laboratories used the same procedure for treatment of monocytic THP-1 cells with KBrO3 (0.5, 1.5 and 4.5 mM for 1 h at 37°C) and subsequent cryopreservation. Results from one laboratory were excluded in the statistical analysis because of technical issues in the Fpg-modified comet assay. All other laboratories found a concentration-response relationship in cryopreserved samples (regression coefficients from 0.80 to 0.98), although with different slopes ranging from 1.25 to 11.9 Fpg-sensitive sites (%DNA in tail) per 1 mM KBrO3. Our results demonstrate that KBrO3 is a suitable positive comet assay control.
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Bromatos/toxicidade , Ensaio Cometa/normas , Dano ao DNA , Monócitos/efeitos dos fármacos , Monitoramento Biológico , DNA/efeitos dos fármacos , DNA/metabolismo , DNA-Formamidopirimidina Glicosilase , Humanos , Monócitos/metabolismo , Estresse Oxidativo , Células THP-1RESUMO
BACKGROUND: During aging, alterations of the intestinal microbial ecosystem can occur contributing to immunosenescence, inflamm-aging and impairment of intestinal barrier function (increased intestinal permeability; IP). In the context of a diet-microbiota-IP axis in older subjects, food bioactives such as polyphenols may play a beneficial modulatory role. METHODS: MaPLE is a project centered on a randomized, controlled cross-over dietary intervention trial [polyphenol-rich diet (PR-diet) versus control diet (C-diet)] targeted to older people (≥ 60 y) living in a well-controlled setting (i.e. nursing home). The 8-week interventions are separated by an 8-week wash-out period. Three small portions per day of selected polyphenol-rich foods are consumed during intervention in substitution of other comparable products within the C-diet. Biological samples are collected before and after each treatment period to evaluate markers related to IP, inflammation, vascular function, oxidative stress, gut and blood microbiomics, metabolomics. A sample size of 50 subjects was defined based on IP as primary outcome. DISCUSSION: Evidence that increasing the consumption of polyphenol-rich food products can positively affect intestinal microbial ecosystem resulting in reduced IP and decreased translocation of inflammogenic bacterial factors into the bloodstream will be provided. The integration of data from gut and blood microbiomics, metabolomics and other IP-related markers will improve the understanding of the beneficial effect of the intervention in the context of polyphenols-microbiota-IP interactions. Finally, findings obtained will provide a proof of concept of the reliability of the dietary intervention, also contributing to future implementations of dietary guidelines directed to IP management in the older and other at risk subjects. TRIAL REGISTRATION: The trial is registered at (ISRCTN10214981); April 28, 2017.
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Polifenóis/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Dieta , Microbioma Gastrointestinal , Humanos , Microbiota , Pessoa de Meia-Idade , Permeabilidade , Reprodutibilidade dos TestesRESUMO
The present study investigates the effect of anthocyanin (ACN), phenolic acid (PA) fractions, and their combination (ACNs:PAs) from wild blueberry powder (Vaccinum angustifolium) on the speed of endothelial cell migration, gene expression, and protein levels of RAC1 and RHOA associated with acute exposure to different concentrations of ACNs and PAs. Time-lapse videos were analyzed and endothelial cell speed was calculated. Treatment with ACNs at 60 µg/mL inhibited endothelial cell migration rate ( P ≤ 0.05) while treatment with PAs at 0.002 µg/mL ( P ≤ 0.0001), 60 µg/mL ( P ≤ 0.0001), and 120 µg/mL ( P ≤ 0.01) significantly increased endothelial cell migration rate compared with control. Moreover, exposure of HUVECs to ACNs:PAs at 8:8 µg/mL ( P ≤ 0.05) and 60:60 µg/mL increased ( P ≤ 0.001) endothelial cell migration. Gene expression of RAC1 and RHOA significantly increased 2 hours after exposure with all treatments. No effect of the above fractions was observed on the protein levels of RAC1 and RHOA. Findings suggest that endothelial cell migration is differentially modulated based on the type of blueberry extract (ACN or PA fraction) and is concentration-dependent. Future studies should determine the mechanism of the differential action of the above fractions on endothelial cell migration.
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Amyotrophic lateral sclerosis (ALS) is a fatal disorder with unknown etiology, in which genetic and environmental factors interplay to determine the onset and the course of the disease. Exposure to toxic metals has been proposed to be involved in the etiology of the disease either through a direct damage or by promoting oxidative stress. In this study we evaluated the concentration of a panel of metals in serum and whole blood of a small group of sporadic patients, all living in a defined geographical area, for which acid mine drainage has been reported. ALS prevalence in this area is higher than in the rest of Italy. Results were analyzed with software based on artificial neural networks. High concentrations of metals (in particular Se, Mn and Al) were associated with the disease group. Arsenic serum concentration resulted lower in ALS patients, but it positively correlated with disease duration. Comet assay was performed to evaluate endogenous DNA damage that resulted not different between patients and controls. Up to now only few studies considered geographically well-defined clusters of ALS patients. Common geographical origin among patients and controls gave us the chance to perform metallomic investigations under comparable conditions of environmental exposure. Elaboration of these data with software based on machine learning processes has the potential to be extremely useful to gain a comprehensive view of the complex interactions eventually leading to disease, even in a small number of subjects.
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Esclerose Lateral Amiotrófica/sangue , Oligoelementos/sangue , Idoso , Esclerose Lateral Amiotrófica/diagnóstico , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-IdadeRESUMO
This study aimed at characterizing the fatty acid (FA) composition of red blood cell (RBC) phospholipids in children and adolescents with primary hyperlipidemia, and to ascertain potential association with serum lipid profile and dietary factors. At this purpose, 54 probands aged 6-17 years were recruited. Subjects showed a low omega-3 index (eicosapentaenoic acid, EPA + docosahexaenoic acid, DHA <4%). Compared to males, females had a trend toward lower levels of total monounsaturated fatty acids (MUFA) and MUFA/saturated fatty acids (SFAs) ratio in RBCs. An inverse relationship between MUFA concentration in RBCs and serum cholesterol or HDL-C/triglycerides ratio was found. Omega-6 polyunsaturated fatty acids (n-6 PUFA) were positively associated to serum HDL-C levels, and inversely to dietary cholesterol. Fiber intake was positively associated with MUFA/SFA ratio. In conclusion, we provide the first experimental data on phospholipid FA composition of RBCs in hyperlipidemic children, showing sex differences and an overall low omega 3-index.
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Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Eritrócitos/química , Ácidos Graxos Ômega-6/sangue , Hiperlipidemias/sangue , Fosfolipídeos/análise , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Peso Corporal , Criança , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Itália , Lipoproteínas HDL/sangue , Masculino , Triglicerídeos/sangueRESUMO
OBJECTIVE: This study aimed to investigate the inter-and intraday repeatability of RHI measured by Endo-PAT in healthy volunteers. METHODS: Interday RHI repeatability was tested in two consecutive days in a group of 31 male subjects. Intraday repeatability was investigated at baseline and after 2 and 4 hour in a group of 16 volunteers. Data were evaluated by analysis of variance. Bland-Altman plot, CV, CR, and ICC were measured. RESULTS: While interday RHI repeatability was found to be reliable (CV: 6.0%; CR: 0.51; ICC: 0.77), multiple evaluations within the same day significantly (P<.001) affected RHI (repeatability of the measurement -CV: 18.8%; CR: 1.26; ICC: 0.48). In particular, a significant increase in RHI occurred at 4 hour compared to 2 hour (+16.8%; P<.05) and to baseline (+30.1%; P<.05). CONCLUSIONS: RHI showed good interday but poor intraday repeatability. Multiple evaluations increased RHI especially in subjects with endothelial dysfunction who improved or reversed their impairment. These results show the potential limitations of multiple Endo-PAT measurements within the same day and the importance of standardizing the protocols before RHI evaluations.
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Artérias/fisiopatologia , Variação Biológica Individual , Hiperemia/fisiopatologia , Adulto , Ritmo Circadiano , Endotélio Vascular/fisiopatologia , Humanos , Masculino , Padrões de Referência , Reprodutibilidade dos Testes , Projetos de Pesquisa , Adulto JovemRESUMO
We previously reported that a portion of blueberries reversed endothelial dysfunction induced by acute cigarette smoking. Since smoking-induced endothelial dysfunction is associated with a condition of oxidative stress, we evaluated whether the observed effect was mediated by modulation of markers of oxidative stress and antioxidant defence. Fourteen out of 16 male healthy smokers previously enrolled, participated in a three-armed randomized controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300g of blueberries) + smoking (one cigarette); control treatment (300ml of water with sugar) + smoking (one cigarette). The cigarette was smoked 100min after blueberry/control/water consumption. Each treatment was separated by 1 week of washout period. Plasma vitamin (C, B12 and folate) and aminothiol concentrations, endogenous [formamidopyrimidine-DNA glycosylase (FPG)-sensitive sites] and oxidatively induced DNA damage (resistance to H2O2-induced DNA damage) in peripheral blood mononuclear cells (PBMCs) were measured at baseline and 20, 60, 90, 120min and 24h after smoking. On the whole, analysis of variance did not show a significant effect of treatment on the modulation of markers of oxidative stress and antioxidant defence but revealed an effect of time for plasma concentrations of vitamin C (P = 0.003), B12 (P < 0.001), folate (P < 0.001), total cysteine (P = 0.007) and cysteine-glycine (P = 0.010) that increased following the three treatments after smoking. No significant effect of treatment was observed for the levels of FPG-sensitive sites (P > 0.05) and H2O2-induced DNA damage (P > 0.05) in PBMCs. In conclusion, the consumption of a single blueberry portion failed to modulate markers of oxidative stress and antioxidant defence investigated in our experimental conditions. Further studies are necessary to elucidate this finding and help clarifying the mechanisms of protection of blueberries against smoking-induced endothelial dysfunction.
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Antioxidantes/metabolismo , Biomarcadores , Mirtilos Azuis (Planta) , Estresse Oxidativo , Fumar/efeitos adversos , Adulto , Análise Química do Sangue , Mirtilos Azuis (Planta)/química , Quebras de DNA , Dano ao DNA , Voluntários Saudáveis , Humanos , Peróxido de Hidrogênio/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Adulto JovemRESUMO
PURPOSE: Blueberries are a rich source of anthocyanins (ACNs) and phenolic acids (PA), which are hypothesized to protect against development of atherosclerosis. The present study examined the effect of an ACN- and PA-rich fractions, obtained from a wild blueberry powder, on the capacity to counteract lipid accumulation in macrophages derived from monocytic THP-1 cells. In addition, we tested the capacity of pure ACNs and their metabolites to alter lipid accumulation. METHODS: THP-1-derived macrophages were incubated with fatty acids (500 µM oleic/palmitic acid, 2:1 ratio) and different concentrations (from 0.05 to 10 µg mL(-1)) of ACN- and PA-rich fractions, pure ACN standards (malvidin, delphinidin and cyanidin 3-glucoside), and metabolites (syringic, gallic and protocatechuic acids). Lipid accumulation was quantified with the fluorescent dye Nile red. RESULTS: Lipid accumulation was reduced at all concentrations of the ACN-rich fraction tested with a maximum reduction at 10 µg mL(-1) (-27.4%; p < 0.0001). The PA-rich fraction significantly reduced the lipid accumulation only at the low concentrations from 0.05 µg mL(-1) to 0.3 µg mL(-1), with respect to the control with fatty acids. Supplementation with pure ACN compounds (malvidin and delphinidin-3-glucoside and its metabolic products (syringic and gallic acid)) reduced lipid accumulation especially at the low concentrations, while no significant effect was observed after cyanidin-3-glucoside and protocatechuic acid supplementation. CONCLUSIONS: The results demonstrated a potential role of both the ACN- and PA-rich fractions and single compounds in the lipid accumulation also at concentrations close to that achievable in vivo.
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Antocianinas/farmacologia , Hidroxibenzoatos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/farmacologia , Aterosclerose/prevenção & controle , Mirtilos Azuis (Planta)/química , Carotenoides/análise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fibras na Dieta/análise , Sacarose Alimentar/análise , Ácidos Graxos/análise , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Glucosídeos/farmacologia , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Pós/química , Oligoelementos/análise , Vitaminas/análiseRESUMO
Research on the potential protective effects of coffee and its bioactives (caffeine, chlorogenic acids and diterpenes) against oxidative stress and related chronic disease risk has been increasing in the last years. The present review summarizes the main findings on the effect of coffee consumption on protection against lipid, protein and DNA damage, as well as on the modulation of antioxidant capacity and antioxidant enzymes in human studies. Twenty-six dietary intervention studies (involving acute and chronic coffee intake) have been considered. Overall, the results suggest that coffee consumption can increase glutathione levels and improve protection against DNA damage, especially following regular/repeated intake. On the contrary, the effects of coffee on plasma antioxidant capacity and antioxidant enzymes, as well as on protein and lipid damage, are unclear following both acute and chronic exposure. The high heterogeneity in terms of type of coffee, doses and duration of the studies, the lack of information on coffee and/or brew bioactive composition, as well as the choice of biomarkers and the methods used for their evaluation, may partially explain the variability observed among findings. More robust and well-controlled intervention studies are necessary for a thorough understanding of the effect of coffee on oxidative stress markers in humans.
Assuntos
Antioxidantes/administração & dosagem , Café/química , Dano ao DNA/efeitos dos fármacos , Antioxidantes/farmacologia , Cafeína/administração & dosagem , Cafeína/farmacologia , Ácido Clorogênico/administração & dosagem , Ácido Clorogênico/farmacologia , Estudos Clínicos como Assunto , Diterpenos/administração & dosagem , Diterpenos/farmacologia , Humanos , Estresse Oxidativo/efeitos dos fármacosRESUMO
Endogenous and oxidatively induced DNA damage, as evaluated by the comet assay, are widely used as biomarkers of oxidative stress in numerous dietary intervention studies. This analysis can be performed on fresh peripheral blood mononuclear cells (PBMCs) or on cryopreserved cells. However, information pertaining to the effects of cryopreservation on DNA damage is often missing, and this may be crucial in studies in which samples are analysed before and after intervention. The purpose of this study was to compare DNA damage in fresh versus cryopreserved PBMCs obtained from subjects following a 6-week intervention with wild blueberry drink or placebo drink. Fresh and 12-month-stored PBMCs were analysed for formamidopyrimidine-DNA glycosylase (FPG)-sensitive sites and H2O2-induced DNA damage. The levels of FPG-sensitive sites were significantly higher in the cryopreserved compared with the fresh cells (P < 0.001), while H2O2-induced DNA damage was significantly lower after storage (P < 0.001). Both the fresh and cryopreserved samples showed reductions in FPG-sensitive sites following the wild blueberry treatment (fresh PBMCs: from 12.50 ± 5.61% to 9.62 ± 3.52%, P = 0.039; cryopreserved PBMCs: from 22.7 ± 6.1% to 19.1 ± 7.0%, P = 0.012). In contrast, the decrease in H2O2-induced DNA damage observed in the cryopreserved cells masked the protective effect of the wild blueberry drink documented in the fresh samples (fresh PBMCs: from 44.73 ± 7.46% to 36.34 ± 9.27%, P < 0.001; cryopreserved PBMCs: from 25.8 ± 4.6% to 23.9 ± 4.6%, P = 0.414). In conclusion, our results suggest that FPG-sensitive sites, and more importantly, H2O2-induced DNA damage could be significantly modified following the long-term storage of samples obtained from individuals participating in a dietary intervention study. Because storage may affect the assessment of the protective role of diet against DNA damage as a marker of oxidative stress, further research is needed.
Assuntos
Biomarcadores/análise , Ensaio Cometa/métodos , Criopreservação/métodos , Dano ao DNA/genética , Comportamento Alimentar/fisiologia , Leucócitos Mononucleares/patologia , Estresse Oxidativo/fisiologia , Análise de Variância , Bebidas/análise , Mirtilos Azuis (Planta)/química , DNA-Formamidopirimidina Glicosilase , Humanos , Peróxido de Hidrogênio , Leucócitos Mononucleares/citologiaRESUMO
This study evaluated the effects of 10-day broccoli (250 g/day) intake on dietary markers and markers of inflammations in young male smokers. A dietary intervention study with a repeated measures crossover design was conducted. Circulating levels of carotenoids, folate, C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 6 receptor (IL-6sR) and adiponectin were measured. Broccoli intake significantly increased plasma levels of folate (+17%) and lutein (+39%), while no significant effect was observed for TNF-α, IL-6, IL-6sR or adiponectin. Plasma CRP decreased by 48% (post-hoc analysis, p < 0.05) following broccoli diet; this resulted to be independent from the plasma variations in lutein and folate. An inverse correlation between lycopene, TNF-α and IL-6sR was observed at baseline. In conclusion, broccoli consumption may reduce CRP levels in smokers, consistent with epidemiologic observations that fruit and vegetable intake is associated with lower circulating CRP concentrations.