Browsing by Issue Date, starting with "2021-11-11"
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- Ingested nanomaterials: impact of digestion process in the physicochemical characteristics and biological consequences in intestinal cellsPublication . Vieira, Adriana; Vital, Nádia; Roque, Rossana; Gramacho, Ana Catarina; Rolo, Dora; Gonçalves, Lídia D.; Bettencourt, Ana; Martins, Carla; Assunção, Assunção; Alvito, Paula; Silva, Maria João; Louro, HenriquetaNanomaterials(NMs) provide a basis for key enabling technologies, in view of their potential to improve many products and processes, namely in food and feed industry. That is the case of titanium dioxide NMs(TiO2 NMs), presenting beneficial properties for a broad range of innovative applications such as food additives, toothpaste, pharmaceuticals, food products, etc., that may drive ingestion. The oral exposure can occur directly, by consumption of products/pharmaceuticals or foods containing NMs, or indirectly, through the ingestion of foods contaminated with NMs released from food-contact materials or environmental sources. As such, the gastrointestinal tract is the first site of contact of the ingested NMs, allowing a systemic exposure if the intestinal barriers is surpassed. This work aimed to investigate how the digestion process affects the physicochemical properties of three different TiO2 NMs(NM-102, NM-103 and NM-105) and their toxic effects on intestinal cells. After undergoing digestion through the standardized static INFOGEST 2.0 in vitro digestion method, the cytotoxicity of the TiO2 NMs was determined in Caco-2 and HT29-MTX-E12 intestinal cells, using the MTT assay. Furthermore, the cytokinesis-blocked micronucleus assay was used to investigate their genotoxicity in both cell lines in order to predict their carcinogenic potential. The results showed that, for one TiO2 NM(NM-105), the digestion caused changes in the hydrodynamic size of the NM and a more pronounced toxicity in HT29-MTX-E12 intestinal cells, as compared to the undigested one. The micronucleus assay suggests effects on the chromosomal integrity in the HT29-MTXE12 cells, for all the tested TiO2 NM especially after the in vitro digestion. Overall, we conclude that including the digestion prior to the in vitro bioassays for the safety evaluation of ingested NMs, allows integrating the physiological modifications that the NMs suffer in the organism, contributing to an improved hazard assessment of ingested NMs.
- Ambient particulate matter exposure interacts with abdominal obesity to increase blood triglyceridesPublication . Gaio, Vânia; Roquette, Rita; Matias Dias, Carlos; Nunes, BaltazarBackground: Blood lipids levels dysregulation represent potential mechanism intermediating the adverse cardiovascular effects of ambient particulate matter (PM) exposure. The present study aims to estimate the effect of particulate matter (PM10) exposure on blood lipid levels (TC, Total Cholesterol; HDL-C, High-Density Lipoprotein Cholesterol; LDL-C, Low-Density Lipoprotein Cholesterol; TG, Triglycerides) in the adult Portuguese mainland population and to assess the potential mediation and/or modification action of abdominal obesity on this effect. Methods: We used data from 2390 participants of the 1st Portuguese Health Examination Survey (INSEF, 2015) with available data on blood lipids parameters and living within a 30km radius of an air quality monitoring station with available PM10 measurements. PM10 concentrations were acquired from the air quality monitoring network of the Portuguese Environment Agency. Generalized linear models were used to assess the effect of 1-year PM10 exposure on blood lipids values. An interaction term was introduced in the models to test the modification action of abdominal obesity. Results: We found an association between long-term exposure to PM10 and non-fasting blood TG levels after adjustment for age, sex, education, occupation, lifestyles related variables and temperature but only in participants with abdominal obesity (1.84% TG increase per each 1 µg/m3 PM10 increment, 95% CI: 0.02%; 3.69%) which is well supported by the sensitivity analysis. Conclusions: Our study demonstrate that even at low levels of exposure, long-term PM10 exposure interacts with abdominal obesity to increase blood TG levels. To the best of our knowledge, this is the first study showing the modification action of abdominal obesity regarding the PM10 effect on a blood lipid parameter. Our findings suggest that reducing both abdominal obesity prevalence and PM10 below current standards would result in additional health benefits for the population.
- PM10 exposure interacts with abdominal obesity to increase blood triglycerides: a cross-sectional linkage studyPublication . Gaio, Vânia; Roquette, Rita; Monteiro, Alexandra; Ferreira, Joana; Lopes, Diogo; Dias, Carlos Matias; Nunes, BaltazarBackground: Blood lipids and glucose levels dysregulation represent potential mechanisms intermediating the adverse cardiovascular effects of ambient particulate matter (PM) exposure. This study aims to estimate the effect of long-term PM10 exposure on blood lipids and glucose levels and to assess the potential mediation and/or modification action of abdominal obesity (AO) (waist-to-height ratio). Methods: Our study was based on 2,390 participants of the first Portuguese Health Examination Survey (INSEF, 2015) with available data on blood lipids and glucose parameters and living within a 30-km radius of an air quality monitoring station with available PM10 measurements. PM10 concentrations were acquired from the air quality monitoring network of the Portuguese Environment Agency. Generalized linear models were used to assess the effect of 1-year PM10 exposure on blood lipids and glucose levels. An interaction term was introduced in the models to test the modification action of AO. Results: We found an association between PM10 and non-fasting blood triglycerides (TG) after adjustment for age, sex, education, occupation, lifestyles-related variables and temperature but only in participants with AO. Per each 1 mg/m3 PM10 increment, there was a 1.84% (95% confidence interval: 0.02–3.69) increase in TG. For the remaining blood lipid and glucose parameters, no associations were found. Conclusions: Our study demonstrates that even at low levels of exposure, long-term PM10 exposure interacts with AO to increase blood TG. Our findings suggest that reducing both AO prevalence and PM10 below current standards would result in additional health benefits for the population.
- Ibuprofen inhibits alternative splicing of tumor related RAC1B in BRAF mutant colon cancer: a role in adjuvant therapy?Publication . Jordan, PeterAbout ibuprofen inhibits alternative splicing of tumor related RAC1B in BRAF mutant colon cancer
- Co-exposure with CeO2NPs results in an antagonistic effect on the cytotoxicity and genotoxicity of TiO2NP on A549 cellsPublication . Rosário, Fernanda; Vilaça, Cláudia; Costa, Carla; Lopes, Cláudia B.; Estrada, Ana C.; Tavares, Daniela S.; Teixeira, João Paulo; Reis, Ana TeresaObjective: Assess the CYTOTOXIC and GENOTOXIC POTENTIAL resulting from titanium dioxide nanoparticles (TiO2NP) and cerium oxide nanoparticles (CeO2NP) co-exposure in human lung epithelial cell line A549.