Browsing by Author "Madureira, Raquel"
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- Applied microbiology on poultry industry: from nutrition to the gut microbiotaPublication . Carvalho, Nelson Mota de; Oliveira, Diana Luazi; Costa, Célia Maria; Pintado, Manuela Estevez; Madureira, RaquelPoultry products (i.e., meat and eggs) are one of the major protein sources for the human diet. The animal’s diet is one of the key elements that the poultry industry has been focused on, to improve the animal’s performance, maintaining their healthy growth and, ultimately, high quality end products. The incorporation of functional ingredients in feed formulations, aiming to provide extra benefits and/or prevent diseases, has been considered efficient in maintaining the animal’s productivity and simultaneously ensure its well-being. Nutrient’s bioavailability varies throughout digestion and absorption within the poultry’s gastrointestinal tract (GIT). A reliable in vitro model, as the one developed and used in this study, capable of mimicking all digestion, absorptive and cecal fermentation processes, is a useful tool to study the potential benefits of feed supplemented with functional and/or bioactive ingredients. The developed in vitro gastrointestinal model simulates the chemical, enzymatic, and mechanical conditions prevailing in the chicken´s GIT, from beak to cecum. Fresh broiler’s cecal samples were used as inoculum for batch cecal fermentation and the impact of different feed formulations, on bacteria modulation, organic acids, and total ammonia nitrogen production, were assessed. Overall, this approach enables to evaluate, as close to reality as possible, the potential of target additives, providing a trustworthy tool for the development of functional feeds.
- C-42. Fenótipo da Síndroma Trico-Dento-Ósseo – o papel da análise capilar no diagnósticoPublication . Assunção, Bibiana Andreia Moreira; Real, Inês Corte; Madureira, Raquel; Ponces, Maria João; Campos, José Reis; Vaz, PaulaIntrodução: A síndroma Trico-dento-óssea (TDOS) é uma doença genética rara, de transmissão autossómica dominante, que se inclui no grupo das displasias ectodérmicas. Caracteriza-se, principalmente, pela presença de hipoplasia do esmalte, taurodontia, cabelo crespo e encaracolado (geralmente apenas presente à nascença), esclerose óssea e, menos frequentemente, por displasia ungueal e dolicocefalia. A variabilidade fenotípica que possui torna difícil, em muitos casos, o seu diagnóstico diferencial com Amelogenesis Imperfecta do tipo hipoplásico-hipomaturado com taurodontia (AIHHT). A identificação de características típicas capilares em microscopia poderá contribuir para este tipo de diagnóstico. Nesse sentido, com este trabalho os autores pretendem apresentar um caso de fenótipo de TDOS, exemplificando como a análise capilar poderá contribuir como ferramenta auxiliar de diagnóstico desta síndroma. Caso clínico: O paciente DRLA, caucasiano, com 22 anos de idade, recorreu a uma consulta médico-dentária na FMDUP para uma avaliação clínica de rotina. Como as peculiaridades deste caso exigiam um tratamento multidisciplinar, quer a avaliação clínica extra e intraoral, quer o plano de tratamento estabelecido foram efetuados pelas Consultas de Genética Orofacial, Ortodontia e Prótese Removível da FMDUP. A partir da anamnese e do exame clínico geral foi confirmado um ligeiro atraso psicomotor, discreta condensação dos ossos cranianos, displasia das unhas e cabelo crespo e ligeiramente encaracolado. Da avaliação intraoral salientaram-se a presença de uma mordida aberta anterior, ausência de oclusão posterior e taurodontia generalizada. As características capilares presentes condicionaram a pesquisa de alterações típicas (morfologia e padrão), confirmadas através de microscopia eletrónica de varrimento (ESBUCP), que contribuiu para o diagnóstico diferencial com a AIHHT. Discussão e conclusões: Perante qualquer situação patológica a impossibilidade de realização de diagnóstico diferencial com patologias similares torna mais complicada a elaboração de um plano de tratamento adequado. Desta forma, a contribuição de ferramentas auxiliares para um correto diagnóstico diferencial, como a análise capilar, visa colmatar esta falha em casos, como o descrito, em que se torna clinicamente difícil esta distinção.
- Cannabidiol and cannabigerol exert antimicrobial activity without compromising skin microbiotaPublication . Luz-Veiga, Mariana; Amorim, Manuela; Pinto-Ribeiro, Inês; Oliveira, Ana L. S.; Silva, Sara; Pimentel, Lígia L.; Rodríguez-Alcalá, Luís M.; Madureira, Raquel; Pintado, Manuela; Azevedo-Silva, João; Fernandes, JoãoCannabidiol (CBD) and cannabigerol (CBG) are two pharmacologically active phytocannabinoids of Cannabis sativa L. Their antimicrobial activity needs further elucidation, particularly for CBG, as reports on this cannabinoid are scarce. We investigated CBD and CBG’s antimicrobial potential, including their ability to inhibit the formation and cause the removal of biofilms. Our results demonstrate that both molecules present activity against planktonic bacteria and biofilms, with both cannabinoids removing mature biofilms at concentrations below the determined minimum inhibitory concentrations. We report for the first time minimum inhibitory and lethal concentrations for Pseudomonas aeruginosa and Escherichia coli (ranging from 400 to 3180 µM), as well as the ability of cannabinoids to inhibit Staphylococci adhesion to keratinocytes, with CBG demonstrating higher activity than CBD. The value of these molecules as preservative ingredients for cosmetics was also assayed, with CBG meeting the USP 51 challenge test criteria for antimicrobial effectiveness. Further, the exact formulation showed no negative impact on skin microbiota. Our results suggest that phytocannabinoids can be promising topical antimicrobial agents when searching for novel therapeutic candidates for different skin conditions. Additional research is needed to clarify phytocannabinoids’ mechanisms of action, aiming to develop practical applications in dermatological use.
- Circular economyeast: saccharomyces cerevisiae as a sustainable source of glucans and its safety for skincare applicationPublication . Sousa, Pedro; Tavares-Valente, Diana; Pereira, Carla F.; Pinto-Ribeiro, Inês; Azevedo-Silva, João; Madureira, Raquel; Ramos, Óscar L.; Pintado, Manuela; Fernandes, João; Amorim, ManuelaGlucans, a polysaccharide naturally present in the yeast cell wall that can be obtained from side streams generated during the fermentation process, have gained increasing attention for their potential as a skin ingredient. Therefore, this study focused on the extraction method to isolate and purify water-insoluble glucans from two different Saccharomyces cerevisiae strains: an engineered strain obtained from spent yeast in an industrial fermentation process and a wild strain produced through lab-scale fermentation. Two water-insoluble extracts with a high glucose content (> 90 %) were achieved and further subjected to a chemical modification using carboxymethylation to improve their water solubility. All the glucans' extracts, water-insoluble and carboxymethylated, were structurally and chemically characterized, showing almost no differences between both yeast-type strains. To ensure their safety for skin application, a broad safety assessment was undertaken, and no cytotoxic effect, immunomodulatory capacity (IL-6 and IL-8 regulation), genotoxicity, skin sensitization, and impact on the skin microbiota were observed. These findings highlight the potential of glucans derived from spent yeast as a sustainable and safe ingredient for cosmetic and skincare formulations, contributing to the sustainability and circular economy.
- Formulation and characterization of loaded rosmarinic acid solid lipid nanoparticlesPublication . Campos, Débora; Madureira, Raquel; Gomes, Ana M. P.; Sarmento, Bruno; Pintado, M. E.
- Natural extracts into chitosan nanocarriers for rosmarinic acid drug deliveryPublication . Silva, Sara Baptista da; Amorim, Manuela; Fonte, Pedro; Madureira, Raquel; Ferreira, Domingos; Pintado, Manuela; Sarmento, BrunoContext: Nanotechnology can be applied to deliver and protect antioxidants in order to control the oxidative stress phenomena in several chronic pathologies. Chitosan (CS) nanoparticles are biodegradable carriers that may protect antioxidants with potent biological activity such as rosmarinic acid (RA) in Salvia officinalis (sage) and Satureja montana (savory) extracts for safe and innovative therapies. Objective: Development and characterization of CS nanoparticles as a stable and protective vehicle to deliver RA for medical applications using natural extracts as sage and savory. Materials and methods: Antioxidant-CS based nanoparticles were prepared by ionic gelation with sodium tripolyphosphate (TPP), at pH 5.8 with a mass ratio of 7:1 (CS:TPP), with a theoretical antioxidant-CS loading of 40-50%. The nanoparticles were then characterized by different methods such as photon correlation spectroscopy, laser Doppler anemometry, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR), high-performance liquid chromatographic (HPLC), association efficiency, and antioxidant activity. Results and discussion: Individual and small sizing nanoparticles, around 300 nm, were obtained. SEM confirmed smooth and spherical nanoparticles after freeze-drying. No chemical interactions were found between antioxidants and CS, after encapsulation, by DSC and FTIR. The association efficiency was 51.2% for RA (with 40% loading) and 96.1 and 98.2% for sage and savory nanoparticles, respectively (both with 50% loading). Antioxidant activity values were higher than 0.0348 eq [Asc. Ac.] g/L/g extract and 0.4251 μmol/eq Trolox/g extract. Conclusion: The extracts under study are promising vehicles for RA drug delivery in CS nanocarriers.
- Release of polyphenols from carnauba wax nanoparticlesPublication . Campos, Débora; Madureira, Raquel; Gomes, Ana M. P.; Sarmento, Bruno; Pintado, Maria ManuelaThe inclusion in foods of compounds with antioxidant activity from rich sources (fruits, aromatic herbs, etc.) has become a common procedure of the food industry. However, when incorporated in food matrix these compounds may interact with matrix components and reduce or loss bioactivity. Hence, the formulation of loaded polyphenols nanoparticles may offer a way to protect such compounds against degradation. In this work, the releasing rates from Solid Lipid Nanoparticles (SLNs) of rosmarinic acid (RA) were tested. Moreover, the effect of selected SLNs upon DNA i.e. antioxidant and prooxidant effects were also evaluated. Different formulations of SLNs were tested, using 0.5% (w/v) of carnauba wax and 1 and 2% (v/v) of polysorbate 80, prepared by a hot melt ultrasonication method. Two types of in vitro release tests were performed. The first approach used a cellulose acetate dialysis bag with molecular weight cut-off of 12 kDa, to evaluate the direct release of RA from the SLNs. The experiment was conducted during 12 h, at 37 ± 0.5 °C with continuous homogenization. The SLNs were dispersed in PBS (0.1 M, pH 7.4), and samples were withdrawn at different time points during the experiment (0, 1, 2, 4, 6, 8, 10 and 12 h). The polyphenol content of samples was analysed by HPLC. The second test using intestinal-based cell co-culture (Caco-2 and HT29-MTX cells), was performed to study the cells permeability to the RA and the possible presence of secondary metabolites from RA. The passage through the cell monolayer and cytotoxicity were evaluated by HPLC and TEER monitoring, respectively. The SLNs were diluted in sterilized ultrapure water, the solution was placed in the apical zone of the cells and samples were taken from the sub-apical zone, at different times. In both in vitro release tests the results have shown high % of RA release. The test using dialysis bag showed 50% RA release after 4h of experiment, and by 12h the % of release reached ca. 90%. On the other side, tests using intestinal cell lines showed that the Caco-2 cells have higher % of passage of RA (ca. 60%) for the sub-apical zone, when compared with the set of Caco-2 and HT29-MTX cells. Finally, SLNs do not attack DNA chains, but also do not protect the DNA, demonstrating that SLNs have a neutral effect, whereas free RA demonstrated a protective effect on the DNA chain.
- The senotherapeutic potential of phytochemicals for age-related intestinal diseasePublication . Costa, Célia Maria; Pedrosa, Sílvia Santos; Kirkland, James L; Reis, Flávio; Madureira, RaquelDuring the last few decades, life expectancy has increased worldwide along with the prevalence of several age-related diseases. Among aging pathways, cellular senescence and chronic inflammation (or “inflammaging”) appear to be connected to gut homeostasis and dysbiosis of the microbiome. Cellular senescence is a state of essentially irreversible cell cycle arrest that occurs in response to stress. Although senescent cells (SC) remain metabolically active, they do not proliferate and can secrete inflammatory and other factors comprising the senescence-associated secretory phenotype (SASP). Accumulation of SCs has been linked to onset of several age-related diseases, in the brain, bones, the gastrointestinal tract, and other organs and tissues. The gut microbiome undergoes substantial changes with aging and is tightly interconnected with either successful (healthy) aging or disease. Senotherapeutic drugs are compounds that can clear senescent cells or modulate the release of SASP and hence attenuate the impact of the senescence-associated pro-inflammatory state. Phytochemicals, phenolic compounds and terpenes, which have antioxidant and anti-inflammatory activities, could also be senotherapeutic given their ability to act upon senescence-linked cellular pathways. The aim of this review is to dissect links among the gut microbiome, cellular senescence, inflammaging, and disease, as well as to explore phytochemicals as potential senotherapeutics, focusing on their interactions with gut microbiota. Coordinated targeting of these inter-related processes might unveil new strategies for promoting healthy aging.
- Use of carnauba wax for the formulation of rosmarinic acid loaded solid lipid nanoparticlesPublication . Campos, Débora; Madureira, Raquel; Gomes, Ana M. P.; Sarmento, Bruno; Pintado, M. E.