Browsing by Author "Pintado, Manuela Estevez"
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- Antioxidants in the prevention and treatment of diabetic retinopathy – a reviewPublication . Silva, Sara Baptista da; Costa, João Paulo; Pintado, Manuela Estevez; Ferreira, Domingos de Carvalho; Sarmento, BrunoDiabetic retinopathy is a disease resulting from diabetic chronic hyperglycemia characterized by microvascular complications in the retina, where neuronal elements responsible for vision are located. It is the main cause of adult blindness in developed countries. Oxidative stress has been widely regarded as the key factor for the emergence of ocular disease and has been involved in increased vascular permeability, disruption of blood-retinal barrier, apoptotic loss of retinal capillary cells, microvascular abnormalities and retinal neovascularization. Dietary supplementation with antioxidants has been related with inhibition of diabetes-induced abnormalities of retinal metabolism, reduction of apoptosis and partial restoration of pericytes. Moreover, the use of topical antioxidants to treat or delaying oxidative stress-related ocular manifestations is still poorly explored, while current diabetic retinopathy therapy includes invasive methods, like surgery. Ocular antioxidant potential therapy represents a non-invasive, safe and less painful methodology, which slows the natural progress of the disease and improves the effectiveness of treatment without significant systemic toxicity. This review underlines the innovative medicines exploited for ocular conditions, a further insight on ocular delivery, benefiting from the advantages of the eye for drug delivery and, additionally, offering new potential applications of antioxidants for the prevention, treatment and control of diabetic retinopathy.
- 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.
- Development of a chicken gastrointestinal tract (GIT) simulation model: impact of cecal inoculum storage preservation conditionsPublication . Carvalho, Nelson Mota de; Costa, Célia Maria; Castro, Cláudia; Saleh, Mayra Anton Dib; Pintado, Manuela Estevez; Oliveira, Diana Luazi; Madureira, Ana RaquelA chicken gastrointestinal tract (GIT) simulation model was developed to help predict the potential effects of feed additives supplementation on chicken’ microbiota. The chemical and enzymatic conditions for oral, gastric, intestinal, and cecum fermentation phases were designed to closely resemble the chicken GIT conditions. For cecum fermentation, the inoculum was obtained from the cecal contents of 18 38-day broiler chickens. The impact of inoculum preservation on bacteria viability was assessed by comparing two methods of preservation with fresh inoculum: (1) 5% dimethyl sulfoxide (DMSO) at −80 °C and (2) 30% glycerol at −20 °C. The fermentation with fresh and frozen (DMSO method) inoculums was performed and compared using standard chicken feed (SCF) and SCF with 1% fructooligosaccharides (FOS), and inoculum control (IC) condition without feed matrix was used as a baseline. Inoculum’s viability was assessed throughout 90 days of storage by culture media platting, while bacterial growth and metabolites production during fermentation was evaluated by quantitative polymerase chain reaction (qPCR), high-performance liquid chromatography (HPLC), and total ammonia nitrogen quantification. The DMSO method was shown to be the most suitable for cecal inoculum storage. Higher growth of beneficial cecal bacteria for fresh inoculum was observed in SCF while for frozen inoculum, was the SCF + FOS condition. Also, frozen inoculum had lower activity of butyrate producers and proteolytic bacteria, showing different fermentation profiles. The GIT model developed showed to be useful to test the effect of feed additives supplementation.
- Effect of blanching, storage and drying conditions on the macro-composition, color and safety of mealworm Tenebrio molitor larvaePublication . Ribeiro, José Carlos; Marques, João Pedro; Fernandes, Tânia R.; Pintado, Manuela Estevez; Carvalho, Susana M. P.; Cunha, Luís MiguelFor food applications, the processing conditions applied to edible insects should present low energy requirements and environmental impact, while also assuring high quality and safety. The main goal of this study was to assess how different blanching, storage and drying conditions influence the quality and safety of Tenebrio molitor larvae. The different operations included blanching treatments (water-immersion or steaming), post-blanching storage (freezing or refrigeration) and drying methods (oven, microwave or freeze dryer). To monitor the impact on the quality of T. molitor dry matter content, water activity (aw), color and macro-nutrient composition were evaluated, while microbiological analyses were performed to assess the impacts on quality and safety. Blanching, particularly immersion-blanching, improved the lightness of the larvae, both before and after drying. Both blanching treatments reduced the Total Viable Count (TVC) and Enterobacteriaceae loads. Regarding the drying methods, freeze drying led to the best color conservation, while drying with an oven led to the lowest moisture content and aw. The application of drying methods further contributed to the reduction of TVC and Enterobacteriaceae, assuring low loads even after 3 months of storage, with the freeze dryer resulting in the lowest reductions, including an increase in yeast and mold count.
- Exploring cannabidiol (CBD) and cannabigerol (CBG) safety profile and skincare potentialPublication . Luz-Veiga, Mariana; Mendes, Adélia; Tavares-Valente, Diana; Amorim, Manuela; Conde, António; Pintado, Manuela Estevez; Moreira, Helena R.; Azevedo-Silva, João; Fernandes, JoãoCannabinoids have long been known for their bioactive properties, with their topical application as anti-inflammatory compounds being at the forefront of research for the past decade. Concurrently, the cosmetic market is a fast-growing industry in constant need of new biomolecules. In this work, we studied the safety profile for topical applications of two cannabinoids: cannabidiol (CBD) and cannabigerol (CBG) and assessed their potential as skin care ingredients. The CBG used in this work resulted from bio-fermentation, and to the best of our knowledge, there are no extensive reports on its safety and usage as a cosmetic ingredient. Our results show that CBD and CBG do not exhibit cytotoxicity, mutagenicity, or skin sensitization. Moreover, we verified an absence of primary irritability, accumulated irritability, phototoxicity and photosensitization, supporting the claims of dermatologically tested, hypoallergenic and non-irritating. While these cannabinoids did not show significant anti-aging effects by altering the extracellular matrix components (both in vitro and ex vivo), they demonstrated promise as protective agents against inflammation caused by air pollution. Specifically, they reduced the levels of pro-inflammatory cytokines, making them valuable in combating environmental skin damage. Overall, our results validate the safety of topical use of cannabinoids, while paving the way for further research in the beauty and personal care market as soothing agents.
- Fatty acids role on obesity induced hypothalamus inflammation: from problem to solution – a reviewPublication . Salsinha, Ana Sofia; Rodríguez-Alcalá, Luis Miguel; Relvas, João B.; Pintado, Manuela EstevezBackground: Obesity has currently reached a worldwide pandemic level, playing a central role in the development of non-communicable diseases and in health care burden. The available drugs for obesity have not achieved the required level of clinical effectiveness and have been associated with severe health side effects. Recent investigations suggest that obesity is more complex as it is associated with altered brain functions. Scope and approach: In this review the hypothalamus inflammation was presented as playing a major role in obesity development and progression. The role of diet, namely western pattern diet, was presented as one of the major responsible for such inflammation focusing on saturated fatty acids role, since they bind to toll-like receptor 4 (TLR 4) triggering inflammatory processes. In contrast, the anti-inflammatory ability of polyunsaturated fatty acids was described and the potential of using conjugated fatty acids in antiobesogenic therapies specifically aiming hypothalamic inflammation was, for the first time, postulated. Key findings and conclusions: Promising hypothalamic anti-inflammatory effects of omega-3 fatty acids, mediated by G protein receptor 120 (GPR120), have been extensively described and present promising results in diet-induced obesity studies. Besides, several in vivo and in vitro studies have demonstrated beneficial effects of conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA) isomers on aspects related to immune function and inflammation, also presenting an anti-inflammatory effect. Moreover, they were successfully described to decrease peripheral obesity effects. Nevertheless, few studies have specifically addressed the effect of those isomers on obesity-induced hypothalamic inflammation and further investigations are warranted.
- Fermented foods and beverages inhuman diet and their influence on gut microbiota and healthPublication . Carvalho, Nelson Mota de; Costa, Eduardo M.; Silva, Sara; Pimentel, Lígia; Fernandes, Tito H.; Pintado, Manuela EstevezDietary changes have accompanied the evolution of humanity and is proven to be fundamental in human evolution and well-being. Nutrition is essential for survival and as a matter of health and equilibrium of the human body. About 1/3 of the human diet is composed by fermented foods and beverages, which are widely distributed and consumed in different societies around the world, no matter the culture and lifestyle. Fermented foods are derived from the fermentation process of different substrates by microorganisms, and more importantly to humans, by those with beneficial characteristics, due to the positive impact on health. Food is transformed in the gut, gaining new proprieties, and increasing its value to the organism. The effects of fermented foods and beverages can be assessed by its influence at the gut microbiota level. Recent studies show the major importance of the gut microbiota role in modulating the organism homeostasis and homeorhesis. More crosslinks between health, gut microbiota and diet are being established especially in the gut–brain axis field. Therefore, the benefits of diet, in particularly of fermented foods and beverages, should be studied and pursued in order to promote a good health status.
- Human and animal in vitro gastrointestinal models: importance and applicationsPublication . Carvalho, Nelson Mota de; Oliveira, Diana Luazi; Costa, Célia Maria; Pintado, Manuela Estevez; Madureira, Ana Raquel
- Importance of gastrointestinal in vitro models for the poultry industry and feed formulationsPublication . Carvalho, Nelson Mota de; Oliveira, Diana Luazi; Saleh, Mayra Anton Dib; Pintado, Manuela Estevez; Madureira, Ana RaquelThe animal’s diet is a crucial factor, as poultry feed formulations influences greatly their development, well-being and final products quality, i.e., meat and eggs. Therefore, the search for feed additives that provide concomitantly better performances, low-cost usage, guarantying the animal well-being and products safety, became a priority to the poultry industry. Although in an early stage, research has been focused on developing the optimal cost-efficient feed formulations, taking into account the chicken’s physiology and function of the gastrointestinal tract and intestinal microbiota. This review discusses a number of concepts and novel approaches towards the optimization of poultry’s feed formulations, by critically encompassing the animal’s growth and performance. Additionally, it highlights the in vitro gastrointestinal models capabilities as a potential solution to test highly nutritive, well-balanced and efficient feed formulations within a circular economy framework.
- In vitro ACE-inhibitory peptide KGYGGVSLPEW facilitates noradrenaline release from sympathetic nerve terminals: relationship with the lack of antihypertensive effect on spontaneous hypertensive ratsPublication . Marques, Cláudia; Amorim, Maria Manuela; Pereira, Joana Odila; Guardão, Luísa; Martins, Maria João; Pintado, Manuela Estevez; Moura, Daniel; Calhau, Conceição; Pinheiro, HélderThis study aimed to validate the antihypertensive activity of the angiotensin-converting enzyme (ACE)-inhibitor whey protein hydrolysate (WPH) obtained through the action of proteolytic enzymes fromCynara Cardunculus. The antihypertensive activity of WPH fractions containing peptides with molecularweight below 3 kDa (Whey < 3 kDa) and 1 kDa (Whey < 1 kDa) along with the antihypertensive activity ofthree potent ACE-inhibitory peptide sequences (DKVGINYW, DAQSAPLRVY and KGYGGVSLPEW), previ-ously identified in WPH, were also investigated. In parallel, the influence of KGYGGVSLPEW (the mostpotent ACE-inhibitory peptide sequence) on AT1receptors (a common pharmacological target of anti-hypertensive therapies beyond ACE), was evaluated. The effect of WPH and fractions (300 mg/kg) andpeptide sequences (5 mg/kg) on systolic, diastolic and mean blood pressure was evaluated by telemetryon Spontaneously Hypertensive Rats (SHR), after single oral administration. Despite their ACE-inhibitoryeffect in vitro, neither WPH, Whey <3 kDa, Whey <1 kDa or peptide sequences exhibited antihyperten-sive activity. In addition, KGYGGVSLPEW was not only devoid of AT1receptor antagonism but, on thecontrary, had a similar effect to that of Ang II by facilitating the noradrenaline release from sympatheticnerve terminals. In vitro ACE blockade does not always correlate with antihypertensive activity and food-derived peptides cannot be classified as antihypertensive agents based exclusively on in vitro assays. Theabsence of an antihypertensive effect may also be a result of the interaction of these compounds withother components of the systems involved in the blood pressure control.