Browsing by Author "Domingues, Valentina"
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- Adipose tissue dysfunction as a central mechanism leading to dysmetabolic obesity triggered by chronic exposure to p,p’-DDEPublication . Pestana, Diogo; Teixeira, Diana; Meireles, Manuela; Marques, Cláudia; Norberto, Sónia; Sá, Carla; Fernandes, Virgínia; Correia-Sá, Luísa; Faria, Ana; Guardão, Luísa; Guimarães, João T.; Cooper, Wendy N.; Sandovici, Ionel; Domingues, Valentina; Delerue-Matos, Cristina; Monteiro, Rosário; Constância, Miguel; Calhau, ConceiçãoEndocrine-disrupting chemicals such as p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), are bioaccumulated in the adipose tissue (AT) and have been implicated in the obesity and diabetes epidemic. Thus, it is hypothesized that p,p'-DDE exposure could aggravate the harm of an obesogenic context. We explored the effects of 12 weeks exposure in male Wistar rats' metabolism and AT biology, assessing a range of metabolic, biochemical and histological parameters. p,p'-DDE -treatment exacerbated several of the metabolic syndrome-accompanying features induced by high-fat diet (HF), such as dyslipidaemia, glucose intolerance and hypertension. A transcriptome analysis comparing mesenteric visceral AT (vAT) of HF and HF/DDE groups revealed a decrease in expression of nervous system and tissue development-related genes, with special relevance for the neuropeptide galanin that also revealed DNA methylation changes at its promoter region. Additionally, we observed an increase in transcription of dipeptidylpeptidase 4, as well as a plasmatic increase of the pro-inflammatory cytokine IL-1β. Our results suggest that p,p'-DDE impairs vAT normal function and effectively decreases the dynamic response to energy surplus. We conclude that p,p'-DDE does not merely accumulate in fat, but may contribute significantly to the development of metabolic dysfunction and inflammation. Our findings reinforce their recognition as metabolism disrupting chemicals, even in non-obesogenic contexts.
- Antibacterial Use of Macroalgae Compounds against Foodborne PathogensPublication . Silva, Aurora; Silva, Sofia A.; Lourenço-Lopes, C.; Jimenez-Lopez, C.; Carpena, M.; Gullón, P.; Fraga-Corral, M.; Domingues, Valentina; Barroso, M. Fátima; Simal-Gandara, J.; Prieto, M. A.The search for food resources is a constant in human history. Nowadays, the search for natural and safe food supplies is of foremost importance. Accordingly, there is a renewed interest in eco-friendly and natural products for substitution of synthetic additives. In addition, microbial contamination of food products during their obtaining and distribution processes is still a sanitary issue, and an important target for the food industry is to avoid food contamination and its related foodborne illnesses. These diseases are fundamentally caused by certain microorganisms listed in this review and classified according to their Gram negative or positive character. Algae have proven to possess high nutritional value and a wide variety of biological properties due to their content in active compounds. Among these capabilities, macroalgae are recognized for having antimicrobial properties. Thus, the present paper revises the actual knowledge of microbial contaminants in the food industry and proposes antimicrobial algal compounds against those pathogenic bacteria responsible for food contamination as valuable molecules for its growth inhibition. The capacity of algae extracts to inhibit some major food pathogen growth was assessed. Moreover, the main applications of these compounds in the food industry were discussed while considering their favorable effects in terms of food safety and quality control
- Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential ContaminationPublication . Soares, Cristina; Sousa, Sara; Machado, Susana; Vieira, Elsa; Carvalho, Ana P.; Ramalhosa, Maria João; Morais, Simone; Correia, Manuela; Oliva-Teles, MT; Domingues, Valentina; Delerue-Matos, CristinaThe total lipid content and lipidic profile of seaweeds harvested in the North Coast and purchased in Portugal were determined in this paper. The amount of total lipids in the different species of seaweeds varied between 0.7 ± 0.1% (Chondrus crispus) and 3.8 ± 0.6% (Ulva spp.). Regarding the fatty acid content, polyunsaturated fatty acids (PUFA) ranged between 0–35%, with Ulva spp. presenting the highest amount; monounsaturated fatty acids (MUFA) varied between 19 and 67%; and saturated fatty acids (SFA) were predominant in C. crispus (45–78%) and Gracilaria spp. (36–79%). Concerning the nutritional indices, the atherogenicity index (AI) was between 0.4–3.2, the thrombogenicity index (TI) ranged from 0.04 to 1.95, except for Gracilaria spp., which had a TI of 7.6, and the hypocholesterolemic/hypercholesterolemic ratio (HH) values ranged between 0.88–4.21, except for Gracilaria spp., which exhibited values between 0.22–9.26. The n6/n3 ratio was below 1 for most of the species evaluated, except for Ascophyllum nodosum, which presented a higher value, although below 2. Considering the PUFA/SFA ratio, seaweeds presented values between 0.11–1.02. The polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHCs) contamination of seaweeds under study was also quantified, the values found being much lower than the maximum levels recommended for foodstuff.
- Brominated flame retardants effect in MCF-7 cells: Impact on vitamin D pathwayPublication . Sousa, Sara; Maia, Maria Luz; Pestana, Diogo; Teixeira, Diana; Ângelo-Dias, Miguel; Martins, Catarina; Borrego, Luís Miguel; Delerue-Matos, Cristina; Calhau, Conceição; Domingues, Valentina; Faria, AnaBrominated flame retardants (BFRs) are persistent environmental pollutants, allowing a constant human exposure which carries several health risks, including the occurrence of breast cancer and vitamin D deficiency. Vitamin D inhibits cell growth and is negatively associated with breast cancer risk. The effect of BFRs in breast cancer and vitamin D pathway is still poorly understood. MCF-7 cells were treated with hexabromocyclododecane (HBCD), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), hexabromobenzene (HBB) and pentabromotoluene (PBT) using short and long-term exposure protocols. Viability, proliferation, migration, cell cycle and gene expression were assessed. Gene expression of hVDBP and hCYP2R1 was also evaluated in hepatocytes. Long-term exposure of MCF-7 cells to HBB increased cell proliferation and migration, consequently increasing MMP-9 expression. The vitamin D pathway was also altered by BFRs: cells appeared less prepared to activate and transport vitamin D and the signaling, action and inactivation mechanisms were diminished in the presence of BFRs. Untreated MCF-7 cells showed cell cycle arrest in phase G0/G1 in the presence of activated vitamin D. However, when MCF-7 cells were exposed to BFRs, cell cycle was arrested in phase G2/M, possibly due to DNA damage. Nonetheless, calcitriol seems to be able to mitigate the effect of some BFRs exposure, e.g. PBT
- Cork - a natural material for linalool controlled releasePublication . Sousa, Sara; Silva, Mário; Gomes, Filipa O.; Domingues, Valentina; Delerue-Matos, CristinaControlled release of aromatic mixtures to the atmosphere is a requirement for scented systems for indoor applications. The product must smell nice, but also be able to last, slowly releasing the perfume over time. Several adsorption materials have been used, for this purpose. In this study, cork was investigated as a potential perfume adsorbent for application in scented drawer sachets and equivalent products. Cork was selected due to its adsorption properties and because it is a natural, renewable, sustainable material. Granulated cork is a significant by‐product in cork industries and it was chosen for adsorption in this work. Linalool, an enantiomeric monoterpene alcohol and one of the main components of several essential oils, was selected as the model compound for adsorption studies. Activated carbon (AC) was used as the reference material. The sorption of linalool to granulated cork and AC was evaluated by HS‐SPME‐GC‐FID. The linalool isotherm on cork was shown to follow a Brunauer‐Deming‐Deming and Teller, Type IV model. The isotherm data on AC can be adjusted to Langmuir and Freundlich models. A maximum adsorption capacity of 3.9x103μg/g was achieved for AC. Desorption studies were performed. Linalool was still released from granulated cork after three equilibrium stages of desorption, whereas only two desorption values were obtained for AC from the equilibrium with highest linalool concentration. Thus, AC demonstrated good adsorption but not good desorption properties. Sorption and desorption studies of linalool from granulated cork, showed that granulated cork could be an excellent material allowing controlled release of the aroma.
- Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements CompositionPublication . Vieira, Elsa F.; Soares, Cristina; Machado, Susana; Oliva-Teles, MT; Correia, Manuela; Ramalhosa, Maria João; Carvalho, A.; Domingues, Valentina; Antunes, Filipa; Morais, Simone; Delerue-Matos, CristinaThis study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.
- Effects of Environmental Organochlorine Pesticides on Human Breast Cancer: Putative Involvement on Invasive Cell AbilityPublication . Pestana, Diogo; Teixeira, Diana; Faria, Ana; Domingues, Valentina; Monteiro, Rosário; Calhau, ConceiçãoHuman exposure to persistent organic pollutants (POPs) is a certainty, even to long banned pesticides like o,p′-dichlorodiphenyltrichloroethane (o,p′-DDT), and its metabolites p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE), and p,p′-dichlorodiphenyldichloroethane (p,p′-DDD). POPs are known to be particularly toxic and have been associated with endocrine-disrupting effects in several mammals, including humans even at very low doses. As environmental estrogens, they could play a critical role in carcinogenesis, such as in breast cancer. With the purpose of evaluating their effect on breast cancer biology, o,p′-DDT, p,p′-DDE, and p,p′-DDD (50–1000 nM) were tested on two human breast adenocarcinoma cell lines: MCF-7 expressing estrogen receptor (ER) α and MDA-MB-231 negative for ERα, regarding cell proliferation and viability in addition to their invasive potential. Cell proliferation and viability were not equally affected by these compounds. In MCF-7 cells, the compounds were able to decrease cell proliferation and viability. On the other hand, no evident response was observed in treated MDA-MB-231 cells. Concerning the invasive potential, the less invasive cell line, MCF-7, had its invasion potential significantly induced, while the more invasive cell line MDA-MB-231, had its invasion potential dramatically reduced in the presence of the tested compounds. Altogether, the results showed that these compounds were able to modulate several cancer-related processes, namely in breast cancer cell lines, and underline the relevance of POP exposure to the risk of cancer development and progression, unraveling distinct pathways of action of these compounds on tumor cell biology.
- Electrochemical genosensors as a new approach on plant DNA detection and quantification for honey authenticationPublication . Morais, Stephanie; Castanheira, Michelle; Santos, Marlene; Domingues, Valentina; Delerue-Matos, Cristina; Barroso, M. FátimaHoney is a natural sweet food product with multiple nutritional and medicinal properties making it a healthy alternative to processed sugars. With the consumers’ recent interest and pur-chase of dietary products the global honey market has greatly increased. To keep up with produc-tion, or simply for financial gain, some producers/companies are now blending pure honey with cheaper substances that possess similar physical characteristics. As there are no notable visible dif-ferences between the pure and adulterated honey, it is extremely difficult to determine the purity of the available honeys. In this study, an electrochemical genosensor based on the sandwich format DNA hybridization reaction between two complementary probes was developed for the detection and quantification of Erica arborea pollen DNA in real samples. Analyzing public database platforms, a 98 base-pair DNA-target probe capable of unequivocally detecting the pollen from E. arborea was selected and designed. The complementary probe to the DNA-target oligonucleotide sequence was then cut into a 28 base-pair thiolated DNA-capture probe and a 70 base-pair fluorescein isothiocya-nate-labelled DNA-signaling probe. To increase the hybridization reaction, a self-assembled mono-layer formed from mixing the DNA-capture probe with mercaptohexanol was employed. Using chronoamperometry, the enzymatic amplification of the electrochemical signal was achieved with a concentration range of 0.03 to 2.00 nM. The DNA from certified E. arborea leaves was extracted using liquid nitrogen and mechanical grinding and the targeted region amplified by PCR. The de-veloped genosensor was successfully applied for the detection and quantification of the DNA con-centration of the extracted E. arborea plant leaves. So, the developed genosensor is a promising cost-effective and innovative analytical method to detect and quantify the DNA concentration of plant DNA in real honey samples.
- Ensuring food safety: electrochemical genosensors for the authentication of plant honey originPublication . Morais, Stephanie L.; Pereira, Eduarda; Castanheira, Michelle; Santos, Marlene; Domingues, Valentina; Delerue-Matos, Cristina; Barroso, M. FátimaHoney is a high-quality and natural ingredient often consumed because of its unique sweet taste and multiple therapeutic and nutritional benefits. These properties are normally intrinsically connected to the regional flora from which the plant pollen is harvested. Hence, the botanical and geographical origins of honeys play a substantial role in the end product's composition. With the recent interest in natural food products many businesses, including the honey industry, have observed a significant expansion in production and market value. However, honey is susceptible to adulteration and, as more and more adulterated honeys are being found on the global market, it is difficult to monitor the safety and quality of all honey products, making honey fraud a serious problem for both consumers and the food industry. Some of the most prevalent fraudulent acts include mislabeling the botanical and geographic origin of honeys and mixing pure honey with inferior honeys, processed sugars, syrups, and other substances. Thus, there is a need to develop an analytical tool that can quickly, cheaply, and easily guarantee the quality and safety of honey. In this study, an electrochemical genosensor, based on a sandwich format DNA hybridization reaction between two complementary probes, for the detection and quantification of two pollen producing plant species: Erica arborea and Castanea sativa were designed and optimized. Analyzing public databases, two synthetic DNA-target sequences capable of unequivocally detecting the pollen from E. arborea and C. sativa were selected and designed. Their complementary oligonucleotide probes were also designed and cut into two distinct sequences: the DNA-capture and DNA-signaling probes. In order to recognize the two plant species in real honey and pollen DNA samples and optimize the hybridization procedure, a mixed selfassembled monolayer of each plant species’ DNA-capture probe and mercaptohexanol was used. Then, the electrochemical signal was enzymatically amplified using chronoamperometric measurements. A concentration range of 0.03 to 2.00 nM for E. arborea and 0.03 to 1.00 nM for C. sativa were obtained. The developed sensors were successfully applied for the detection and quantification of the two plant species in real plant samples and, thus, indicate the botanic origin of honeys. Therefore, the developed electrochemical genosensors are a viable and affordable analytical tool to authenticate the botanical origin of honeys, ensuring honey quality and safety for consumers as well as the industries.
- Exposure assessment to bisphenol A (BPA) in Portuguese children by human biomonitoringPublication . Correia-Sá, Luísa; Kasper-Sonnenberg, Monika; Schütze, André; Pälmke, Claudia; Norberto, Sónia; Calhau, Conceição; Domingues, Valentina; Koch, Holger M.Exposure to bisphenol A (BPA) is known to be widespread and available data suggests that BPA can act as an endocrine disruptor. Diet is generally regarded as the dominant BPA exposure source, namely through leaching to food from packaging materials. The aim of this study was to evaluate the exposure of 110 Portuguese children (4-18 years old), divided in two groups: the regular diet group (n = 43) comprised healthy normal weight/underweight children with no dietary control; the healthy diet group (n = 67) comprised children diagnosed for obesity/overweight (without other known associated diseases) that were set on a healthy diet for weight control. First morning urine samples were collected and total urinary BPA was analyzed after enzymatic hydrolysis via on-line HPLC-MS/MS with isotope dilution quantification. Virtually, all the children were exposed to BPA, with 91% of the samples above the LOQ (limit of quantification) of 0.1 μg/L. The median (95th percentile) urinary BPA levels for non-normalized and creatinine-corrected values were 1.89 μg/L (16.0) and 1.92 μg/g creatinine (14.4), respectively. BPA levels in the regular diet group were higher than in the healthy diet group, but differences were not significant. Calculated daily BPA intakes, however, were significantly higher in children of the regular diet group than in children of healthy diet group. Median (95th percentile) daily intakes amounted to 41.6 (467) ng/kg body weight/day in the regular diet group, and 23.2 (197) ng/kg body weight/day in the healthy diet group. Multiple logistic regression analysis revealed that children in the healthy diet group had 33% lower intakes than children in the regular diet group (OR 0.67; 95% CI 0.51-0.89). For both groups, however, urinary BPA levels and daily BPA intakes were within the range reported for other children's populations and were well below health guidance values such as the European Food Safety Authority (EFSA) temporary tolerable daily intake (t-TDI) of 4 μg/kg body weight/day. In addition, lower daily BPA intakes were more likely linked with the inherent dietary approach rather than with high BMI or obesity.
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