Loading...
7 results
Search Results
Now showing 1 - 7 of 7
- Effect of food preparations on in vitro bioactivities and chemical components of fucus vesiculosusPublication . André, Rebeca; Guedes, Laura; Melo, Ricardo; Ascensão, Lia; Pacheco, Rita; Vaz, Pedro D.; Serralheiro, Maria LuisaFucus vesiculosus is a brown macroalgae used in food and generally considered safe to be consumed, according to EU Directive (EC 258/97). The aim of this study is to analyze the e_ect of food preparation on F.vesiculosus of di_erent origins on what concerns its chemical constituents and final bioactivities. The aqueous extract of the seaweeds were obtained at di_erent temperatures, similar to food preparation and then purified by SPE. The compound identification was carried out by Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS/MS) and algae extracts microstructure were observed by Scanning Electron Microscopy (SEM). The activities were determined by using antioxidant activity, inhibition of acetylcholinesterase (AChE) and 3-hidroxi-3-methyl-glutaril-CoA (HMG-CoA) reductase (HMGR) together with Caco-2 cells line simulating the intestinal barrier. The activity of AChE and the HMGR were inhibited by the extracts giving IC50 values of 15.0 _ 0.1 _g/mL and 4.2 _ 0.1 _g/mL, respectively and 45% of the cholesterol permeation inhibition. The main compounds identified were phlorotannins and peptides derivatives. The mode of preparation significantly influenced the final bioactivities. Moreover, the in vitro results suggest that the preparation of F. vesiculosus as a soup could have hypercholesterolemia lowering effect.
- BioMol4Health_Biological chemistry: longevity in a cup of teaPublication . RESSAISSI, Asma; Fale, Pedro; Pacheco, Rita; Serralheiro, Maria LuisaInfusions have been studied on what concerns Alzheimer Disease, digestive process, diet cholesterol absorption and its biosynthesis inhibition. In the first two cases the inhibition of acetylcholinesterase (AChE) has been addressed. In the last two situations, an in vitro intestinal barrier has been simulated and the inhibition of the regulator enzyme (HMGR) in cholesterol biosysnthesis pathway has been studied. AChE has been the target of infusions inhibitory activity as its inhibition has been seen to improve cognition and global functioning1 in AD suffering people and to improve the gastrointestinal motility2. Given to lab animals the compounds presente in the infusions were able to reach the brain and inhibit the enzyme3. The effect of infusions on cholesterol bioavailability pointed out that some infusions were able to reduce cholesterol permeation4 and also to have some inhibitory activity5. Studies have indicated that phenolics are able to modify the cell proteome6. The infusions have also been shown to modify the amount of cholesterol transporter proteins in cell membrane and this maybe one of possible explanations for the reduction in cholesterol transport detected under the effect of infusions, on some people ando n simulated intestinal barrier.
- Melanin: production from cheese bacteria, chemical characterization, and biological activitiesPublication . Ferraz, Ana Rita; Pacheco, Rita; Vaz, Pedro D.; Pintado, C. M. B. S.; Ascensão, Lia; Serralheiro, Maria LuisaPigments are compounds of importance to several industries, for instance, the food industry, where they can be used as additives, color intensifiers, and antioxidants. As the current trend around the world is shifting to the use of eco-friendly commodities, demand for natural dyes is increasing. Melanins are pigments that are produced by several microorganisms. Pseudomonas putida ESACB 191, isolated from goat cheese rind, was described as a brown pigment producer. This strain produces a brown pigment via the synthetic Mueller-Hinton Broth. This brown compound was extracted, purified, analyzed by FTIR and mass spectrometry, and identified as eumelanin. The maximum productivity was 1.57 mg/L/h. The bioactivity of eumelanin was evaluated as the capacity for scavenging free radicals (antioxidant activity), EC50 74.0 & PLUSMN; 0.2 mu g/mL, and as an acetylcholinesterase inhibitor, with IC50 575 & PLUSMN; 4 mu g/mL. This bacterial eumelanin did not show cytotoxicity towards A375, HeLa Kyoto, HepG2, or Caco2 cell lines. The effect of melanin on cholesterol absorption and drug interaction was evaluated in order to understand the interaction of melanin present in the cheese rind when ingested by consumers. However, it had no effect either on cholesterol absorption through an intestinal simulated barrier formed by the Caco2 cell line or with the drug ezetimibe.
- Inhibition of HMG-CoA reductase activity and cholesterol permeation through Caco-2 cells by caffeoylquinic acids from Vernonia condensata leavesPublication . Arantes, Ana A.; Fale, Pedro L.; Costa, Larissa C. B.; Pacheco, Rita; Ascensão, Lia; Serralheiro, Maria LuísaThe aim ofthis study was to provide scientific knowledge to supportthe use of Vernonia condensata Baker, Asteraceae, beverages for their alleged hypocholesterolemic properties by testing their action as HMGCoA reductase inhibitors and their capacity to lower dietary cholesterol permeation. Chlorogenic acid, and other caffeoylquinic acids derivatives were identified as the main components of these beverages by LC–MS/MS. No changes in the composition were notice after the in vitro gastrointestinal digestion and no toxicity against Caco-2 and HepG2 cell lines was detected. Cholesterol permeation through Caco-2 monolayers was reduced in 37% in the presence of these herbal teas, and the caffeoylquinic acids permeated the monolayers in 30–40% of their initial amount in 6 h. HMG-CoA reductase activity was reduced with these beverages, showing an IC50 of 217 g ml−1. It was concluded that caffeoylquinic acids, the major components, justified 98% of the enzyme inhibition measured.
- Nanoformulation of seaweed eisenia bicyclis in albumin nanoparticles targeting cardiovascular diseases: In vitro and in vivo evaluationPublication . Pinto, Sofia; Gaspar, Maria Manuela; Ascensão, Lia; Faísca, Pedro; Reis, Catarina; Pacheco, RitaNatural products, especially those derived from seaweeds, are starting to be seen as effective against various diseases, such as cardiovascular diseases (CVDs). This study aimed to design a novel oral formulation of bovine albumin serum nanoparticles (BSA NPs) loaded with an extract of Eisenia bicyclis and to validate its beneficial health effects, particularly targeting hypercholesterolemia and CVD prevention. Small and well-defined BSA NPs loaded with Eisenia bicyclis extract were successfully prepared exhibiting high encapsulation efficiency. Antioxidant activity and cholesterol biosynthesis enzyme 3-hydroxy-3 methylutaryl coenzyme A reductase (HMGR) inhibition, as well as reduction of cholesterol permeation in intestinal lining model cells, were assessed for the extract both in free and nanoformulated forms. The nanoformulation was more efficient than the free extract, particularly in terms of HMGR inhibition and cholesterol permeation reduction. In vitro cytotoxicity and in vivo assays in Wistar rats were performed to evaluate its safety and overall effects on metabolism. The results demonstrated that the Eisenia bicyclis extract and BSA NPs were not cytotoxic against human intestinal Caco-2 and liver HepG2 cells and were also safe after oral administration in the rat model. In addition, an innovative approach was adopted to compare the metabolomic profile of the serum from the animals involved in the in vivo assay, which showed the extract and nanoformulation's impact on CVD-associated key metabolites. Altogether, these preliminary results revealed that the seaweed extract and the nanoformulation may constitute an alternative natural dosage form which is safe and simple to produce, capable of reducing cholesterol levels, and consequently helpful in preventing hypercholesterolemia, the main risk factor of CVDs.
- Brown algae potential as a functional food against hypercholesterolemia: reviewPublication . André, Rebeca; Pacheco, Rita; Bourbon, Mafalda; Serralheiro, Maria LuisaBrown algae have been part of the human diet for hundreds of years, however, in recent years, commercial and scientific interest in brown algae has increased due to the growing demand for healthier diet by the world population. Brown algae and its metabolites, such as carotenoids, polysaccharides, phlorotannins, and proteins, have been associated with multiple beneficial health effects for different diseases, such as cardiovascular diseases, one of the main causes of death in Europe. Since high blood cholesterol levels are one of the major cardiovascular risks, this review intends to provide an overview of current knowledge about the anti-hypercholesterolemic effect of different brown algae species and/or their isolated compounds.
- Cholesterol transporter proteins in HepG2 cells can be modulated by phenolic compounds present in Opuntia ficus-indica aqueous solutionsPublication . RESSAISSI, Asma; ATTIA, Nebil; Pacheco, Rita; Fale, Pedro; Serralheiro, Maria LuisaIncreased blood cholesterol is a risk factor for atherosclerotic cardiovascular disease. This study tested the hypothesis that phenolic compounds can modulate the level of cholesterol transporters including Niemann-Pick C1-like 1 (NPC1L1) and ATP-binding cassette transporters in liver cells. HepG2 cells, used as a model of hepatocytes, showed a decrease in the abundance of cholesterol transporters comparatively to the control when treated with the Opuntia ficus-indica's cladodes decoction. The decrease was between 13-70%, 25-60%, 9-60% and 23-60% for NPC1L1, ABCA1, ABCG5 and ABCG8 transporters, respectively, when using between 0.15 and 0.35 mg/mL of decoction in the culture medium. FTIR analysis showed changes in the amount of RNA, which may be the cause of the decrease in the level of several proteins. These in vitro results pave the way to a molecular explanation for the decoction of cladodes effect on cholesterol levels as it reduced the membrane cholesterol transporter proteins, NPC1L1, ABCG5/ABCG8 and ABCA1, in HepG2 cells.