Percorrer por autor "Fontes, Ana Luiza"
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- Allergic inflammation triggers dyslipidemia via IgG signallingPublication . Fernández-Gallego, Nieves; Castillo-González, Raquel; Moreno-Serna, Lucía; García-Cívico, Antonio J.; Sánchez-Martínez, Elisa; López-Sanz, Celia; Fontes, Ana Luiza; Pimentel, Lígia L.; Gradillas, Ana; Obeso, David; Neuhaus, René; Ramírez-Huesca, Marta; Ruiz-Fernández, Ignacio; Nuñez-Borque, Emilio; Carrasco, Yolanda R.; Ibáñez, Borja; Martín, Pilar; Blanco, Carlos; Barbas, Coral; Barber, Domingo; Rodríguez-Alcalá, Luis M.; Villaseñor, Alma; Esteban, Vanesa; Sánchez-Madrid, Francisco; Jiménez-Saiz, RodrigoBackground: Allergic diseases begin early in life and are often chronic, thus creating an inflammatory environment that may precede or exacerbate other pathologies. In this regard, allergy has been associated to metabolic disorders and with a higher risk of cardiovascular disease, but the underlying mechanisms remain incompletely understood. Methods: We used a murine model of allergy and atherosclerosis, different diets and sensitization methods, and cell-depleting strategies to ascertain the contribution of acute and late phase inflammation to dyslipidemia. Untargeted lipidomic analyses were applied to define the lipid fingerprint of allergic inflammation at different phases of allergic pathology. Expression of genes related to lipid metabolism was assessed in liver and adipose tissue at different times post-allergen challenge. Also, changes in serum triglycerides (TGs) were evaluated in a group of 59 patients ≥14 days after the onset of an allergic reaction. Results: We found that allergic inflammation induces a unique lipid signature that is characterized by increased serum TGs and changes in the expression of genes related to lipid metabolism in liver and adipose tissue. Alterations in blood TGs following an allergic reaction are independent of T-cell-driven late phase inflammation. On the contrary, the IgG-mediated alternative pathway of anaphylaxis is sufficient to induce a TG increase and a unique lipid profile. Lastly, we demonstrated an increase in serum TGs in 59 patients after undergoing an allergic reaction. Conclusion: Overall, this study reveals that IgG-mediated allergic inflammation regulates lipid metabolism.
- Allergic inflammation triggers dyslipidemia via IgG signallingPublication . Fernández-Gallego, Nieves; Castillo-González, Raquel; Moreno-Serna, Lucía; García-Cívico, Antonio J.; Sánchez-Martínez, Elisa; López-Sanz, Celia; Fontes, Ana Luiza; Pimentel, Lígia L.; Gradillas, Ana; Obeso, David; Ramírez-Huesca, Marta; Ruiz-Fernández, Ignacio; Nuñez-Borque, Emilio; Carrasco, Yolanda R.; Ibáñez, Borja; Martín, Pilar; Blanco, Carlos; Barbas, Coral; Barber, Domingo; Rodríguez-Alcalá, Luis M.; Villaseñor, Alma; Esteban, Vanesa; Sánchez-Madrid, Francisco; Jiménez-Saiz, RodrigoAllergic diseases begin early in life and are often chronic, thus creating an inflammatory environment that may lead to metabolic disorders, although the underlying mechanisms remain incompletely understood. Here, we show that allergic inflammation induces diet-independent dyslipidemia in a mouse model of allergy and atherosclerosis. Using untargeted lipidomics in mouse plasma, we found that allergic inflammation induces a unique lipid signature that extends beyond acute and late inflammation and that is characterized by triglyceride (TG) changes in circulation. Alterations in blood TGs following an allergic reaction are independent of T-cell-driven late phase inflammation. On the contrary, the humoral component is sufficient to induce a TG increase and a unique lipid profile through the IgG-mediated alternative pathway of anaphylaxis. Lastly, we demonstrated blood TG changes in patients after undergoing an allergic reaction. Overall, this study reveals the importance of IgG-mediated allergic inflammation insofar as it regulates lipid metabolism, which may contribute to atherosclerosis and, ultimately, to cardiovascular events.
- Characterization of potential CLA-producing strains according to LA tolerancePublication . Fontes, Ana Luiza; Pimentel, Lígia; Salsinha, Ana Sofia; Cardoso, Beatriz; Andrade, José Carlos; Rodriguéz-Alcalá, Luís Miguel; Gomes, Ana MariaBackground: Conjugated linoleic acid (CLA) isomers are naturally produced from dietary linoleic acid (LA) by ruminal bacteria. However, strains of lactobacilli, bifidobacteria and propionibacteria have also demonstrated the ability to produce those bioactive fatty acids. In vitro studies normally test CLA production at 0.5 mg/mL of LA, but possibly some strains can tolerate higher concentrations and if they are producers, CLA yields may probably be higher. This work aims to determine the maximum LA concentration that potential CLA-producing strains can tolerate in an in vitro production assay. Method: Thirty five lactobacilli, 17 bifidobacteria, 1 propionibacterium and 1 lactococcus strains were submitted to a modified method described by Roméro-Pérez et al. [1]. Activated strains were inoculated in MRS agar plates containing 1, 2 or 5 mg/mL of LA for 48 h at 37 ºC. Strains from the agar plate at the highest LA tolerated concentration were then spiked into MRS broth with LA in a 96-well microplate and subsequently incubated at 37 ºC for 48 h; growth curves were recorded at 600, 620 and 660 nm in a microplate reader. Cultures without substrate were used as control. Agar plates experiment was carried out in duplicate and microplate experiment in triplicate. Results & Conclusions: Among the strains tested, 18 (~33%) could not grow at the lowest LA concentration assayed, having considered their tolerance below 1 mg/mL. A group of 16 strains showed growth at 1 mg/mL of LA, 8 tolerated up to 2 mg/mL and 12 up to 5 mg/mL. At 5 mg/mL lactobacilli was the dominant group, whereas at 2 mg/mL was bifidobacteria. At <1 mg/mL and 1 mg/mL the distribution of lactobacilli and bifidobacteria was similar. The propionibacterium and the lactococcus strains could grow a 1 mg/mL. In conclusion, potential CLA-producing strains exhibit different LA tolerance degrees. This is a parameter to consider in future production tests.
- Does the presence of linoleate isomerase gene implies conjugated linoleic acid production?Publication . Calzada, Javier; Salsinha, Sofia; Pimentel, Lígia; Fontes, Ana Luiza; Gomes, Ana; Arqués, Juan; Rodríguez-Alcalá, Luis Miguel
- Effect of pufa substrates on fatty acid profile of bifidobacterium breve Ncimb 702258 and CLA/CLNA production in commercial semi-skimmed milkPublication . Fontes, Ana Luiza; Pimentel, Lígia; Rodríguez-Alcalá, Luis Miguel; Gomes, Ana MariaCurrent research on lipids is highlighting their relevant role in metabolic/signaling pathways. Conjugated fatty acids (CFA), namely isomers of linoleic and linolenic acid (i.e. CLA and CLNA, respectively) can positively modulate inflammation processes and energy metabolism, promoting anti-carcinogenic and antioxidant effects, improved lipid profiles and insulin resistance, among others. Bioactive doses have been indicated to be above 1 g/d, yet these cannot be achieved through a moderate intake (i.e. 1–2 servings) of natural sources, and certain CLA-containing products have limited commercial availability. Such handicaps have fueled research interest in finding alternative fortification strategies. In recent years, screening of dairy products for CFA-producing bacteria has attracted much attention and has led to the identification of some promising strains, including Bifidobacterium breve NCIMB 702258. This strain has shown interesting producing capabilities in model systems as well as positive modulation of lipid metabolism activities in animal studies. Accordingly, the aim of this research work was to assay B. breve NCIMB 702258 in semi-skimmed milk to produce a probiotic fermented dairy product enriched in bioactive CLA and CLNA. The effect of substrates (LA, α-LNA and γ-LNA) on growth performance and membrane fatty acids profile was also studied, as these potential modifications have been associated to stress response. When tested in cys-MRS culture medium, LA, α-LNA and γ-LNA impaired the fatty acid synthesis by B. breve since membrane concentrations for stearic and oleic acids decreased. Variations in the C18:1 c11 and lactobacillic acid concentrations, may suggest that these substrates are also affecting the membrane fluidity. Bifidobacterium breve CFA production capacity was first assessed in cys-MRS with LA, α-LNA, γ-LNA or all substrates together at 0.5 mg/mL each. This strain did not produce CFA from γ-LNA, but converted 31.12% of LA and 68.20% of α-LNA into CLA and CLNA, respectively, after incubation for 24 h at 37 °C. In a second phase, B. breve was inoculated in a commercial semi-skimmed milk with LA, α-LNA or both at 0.5 mg/mL each. Bifidobacterium breve revealed a limited capacity to synthesize CLA isomers, but was able to produce 0.062–0.115 mg/mL CLNA after 24 h at 37 °C. However, organoleptic problems were reported which need to be addressed in future studies. These results show that although CFA were produced at too low concentrations to be able to achieve solely the bioactive dose in one daily portion size, fermented dairy products are a suitable vector to deliver B. breve NCIMB 702258.
- Influence of shaking and viable cell numbers on microbial conjugated linoleic acid (CLA) productionPublication . Fontes, Ana Luiza; Pimentel, Lígia; Salsinha, Ana Sofia; Rodriguez, Juan Miguel; Domingues, MR; Rodríguez-Alcalá, Luís M.; Gomes, Ana Maria
- Microbial conjugated linolenic acid-enriched fermented milk using lipase-hydrolyzed flaxseed oil: biochemical, organoleptic and storage traitsPublication . Fontes, Ana Luiza; Pimentel, Lígia L.; Monteiro, Maria João P.; Domingues, M. Rosário; Rodríguez-Alcalá, Luis Miguel; Gomes, Ana MariaThe bioactive conjugated linolenic acid (CLNA) can be microbiologically produced by different probiotic strains when in the presence of α-linolenic acid (α-LNA). Food matrices are a good vector, such as has been previously demonstrated with fermented milk enriched with microbial CLNA by Bifidobacterium breve DSM 20091 from lipase-hydrolyzed flaxseed oil. The aim of the present work was to further assess the nutritional, biochemical and organoleptic properties of the developed dairy product, as well as its storage stability throughout 28 days at 4 °C, proving its suitability for consumption. Milk lactose hydrolyzed into glucose (0.89 g/100 g) and galactose (0.88 g/100 g), which were further metabolized into lactic (0.42 g/100 g), acetic (0.44 g/100 g) and propionic (0.85 g/100 g) acids. Titratable acidity reached 0.69% and pH 4.93. Compared with the control (no CLNA), fat content was slightly higher (2.0 g/100 g). Acetic acid was the major volatile (83.32%), lacking important dairy flavor contributors, like acetaldehyde. Sensory analysis revealed predominant astringency and bitterness. No microbial concerns arose during storage, but the CLNA content increased, and some saturated fatty acids seemed to oxidize. In conclusion, the CLNA-enriched fermented milk revealed reasonable compositional properties, yet further improvements are needed for optimal consumer acceptance and a prolonged shelf-life.
- Microbiological in vivo production of CLNA as a tool in the regulation of host microbiota in obesity controlPublication . Pimentel, Lígia Leão; Fontes, Ana Luiza; Salsinha, Ana Sofia; Cardoso, Beatriz Batista; Gomes, Ana Maria; Rodríguez-Alcalá, Luís MiguelMetabolic disorders associated with dietary patterns have become a social and economic problem. Obesity is indeed considered a central feature that increases the risks associated with a vast array of diseases (insulin resistance, type 2 diabetes, fatty liver disease, atherosclerosis, hypertension, stroke, cancer, and asthma), with significant morbidity and mortality. Although lipids may be involved in the development of these illnesses, recent studies have stated their role as cellular mediators and they have been assayed as bioactive compounds in possible treatments. Clear examples are the conjugated isomers of linoleic acid (CLA), which have been associated with antiatherogenic, antioxidative, immunostimulation, and body fat reduction activities. Recently, increased interest in other conjugated PUFAs has emerged, linked to the health-promoting properties of conjugated linolenic acid isomers (CLnA) like C18:3 c9t11c15 (rumelenic acid, RLA). These fatty acids combine in the same molecule a double conjugated bond system with the n3 structure of linolenic acid (ALA; C18:3 c9c12c15) resulting in a high bioactive potential. Animal studies have revealed that CLnA regulates leptin production and increases β-oxidation in the liver thus reducing perirenal and epididymal adipose tissue. Elsewhere it was reported that RLA increased PPARα levels in adipocytes, which suggests that it is a candidate functional ingredient for use in the prevention of obesity, diabetes, and dyslipidemia. CLA and CLnA are natural fatty acids (FAs) mainly found in dairy products and beef, because they are produced as intermediates of the biohydrogenation pathway of PUFAs by ruminal bacteria. Therefore it is hypothesized that other microorganisms may also be able to produce CLA and conjugated FAs. Indeed, recent investigations demonstrated that it is possible to elaborate fermented dairy products containing CLA and CLnA produced by these bacteria. Other authors have identified Bifidobacterium strains with a high rate of substrate conversion to yield CLA, CLnA, and stearidonic acids producing these FAs in vivo, increasing the RA concentration in murine and pigs livers as well as DHA and EPA in mice adipose tissue. An important issue arises from these results: host fatty acid composition can be manipulated by oral administration of CLA-producing microorganisms. In the last 5 years an increasing number of studies have found strong evidence of the role not only of diet but also of human gut microbiota in the development of diabetes and obesity. Indeed, host microbiota regulates the content of triglycerides, cholesterol esters, sphingomyelin, and phosphatidylcholine in the plasma, liver, and adipose tissue as well as energy metabolites. This chapter will review the current state-of-the-art microbiological in vivo production of CLA and CLnA and its effect on host microbiota and health.
- Novel lipids to regulate obesity and brain function: comparing available evidence and insights from QSAR in silico modelsPublication . Teixeira, Francisca S.; Costa, Paula T.; Soares, Ana M. S.; Fontes, Ana Luiza; Pintado, Manuela E.; Vidigal, Susana S. M. P.; Pimentel, Lígia L.; Rodríguez-Alcalá, Luís M.Lipid molecules, such as policosanol, ergosterol, sphingomyelin, omega 3 rich phosphatidylcholine, α-tocopherol, and sodium butyrate, have emerged as novel additions to the portfolio of bioactive lipids. In this state-of-the-art review, we discuss these lipids, and their activity against obesity and mental or neurological disorders, with a focus on their proposed cellular targets and the ways in which they produce their beneficial effects. Furthermore, this available information is compared with that provided by in silico Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) models in order to understand the usefulness of these tools for the discovery of new bioactive compounds. Accordingly, it was possible to highlight how these lipids interact with various cellular targets related to the molecule transportation and absorption (e.g., α-tocopherol transfer protein for α-Tocopherol, ATP-binding cassette ABC transporters or Apolipoprotein E for sphingomyelins and phospholipids) or other processes, such as the regulation of gene expression (involving Sterol Regulatory Element-Binding Proteins for ergosterol or Peroxisome Proliferator-Activated Receptors in the case of policosanol) and inflammation (the regulation of interleukins by sodium butyrate). When comparing the literature with in silico Quantitative Structure–Activity Relationship (QSAR) models, it was observed that although they are useful for selecting bioactive molecules when compared in batch, the information they provide does not coincide when assessed individually. Our review highlights the importance of considering a broad range of lipids as potential bioactives and the need for accurate prediction of ADMET parameters in the discovery of new biomolecules. The information presented here provides a useful resource for researchers interested in developing new strategies for the treatment of obesity and mental or neurological disorders.
- Perspectives on the development of CLA/CLNA-enriched milk through in situ microbial productionPublication . Fontes, Ana Luiza; Pimentel, Lígia; Calzada, Javier; Salsinha, Ana Sofia; Rodríguez, Juan Miguel; Arqués, Juan; Domingues, Maria do Rosário; Gomes, Ana Maria; Rodríguez-Alcalá, Luis MiguelOver the past decade several food-derived lipids with potential bioactive properties to be used in the development of innovative functional foods have been identified. These include conjugated linoleic (CLA) and conjugated linolenic (CLNA) acids with well described anti- inflammatory, anti-obesity and anticarcinogenic properties. Limited availability in their natural sources (e.g. ruminants’ milk and meat or vegetable oils) has driven studies on in situ microbial production in dairy products to improve CLA/CLNA daily intake. Several probiotic strains have been reported to produce CLA/CLNA isomers using linoleic (LA) and alpha-linolenic (α-LNA) acids as precursor substrates, respectively. This research work aimed to evaluate the viability of developing a CLA/CLNA-enriched milk through in situ microbial production at a laboratory scale. A combination of genetic screening, substrate tolerance and production assays, identified three CLA/CLNA-producing candidates from a pool of 85 probiotic bacteria. Since Bifidobacterium breve DSM 20091 stood out from the others with CLA/CLNA production yields around 0.3 mg/mL, it was selected to proceed with milk CLA/CLNA-enrichment. Seeking to explore industrial viability, edible vegetable oils were applied as substrate sources instead, namely soybean (SBO; rich in LA) and flaxseed (FSO; rich in α-LNA) oils, which had been previously hydrolyzed with Candida rugosa lipase. Microbial CLA/CLNA-enrichment of pasteurized bovine milk was tested with each hydrolyzed oil, individually or in combination, to provide 0.5 mg/mL of LA and/or α-LNA. Viable cell numbers of B. breve achieved 9 log cycles upon 24 h fermentation. Highest CLA/CLNA-enrichment was achieved using FSO alone (~0.4 mg/g), where CLNA isomers were those mainly produced. Surprisingly, only traces of CLA were found, either with SBO alone or in combination. Milk enrichment was further assayed with FSO alone to concentrations up to 10 mg/mL α-LNA, where at 2 mg/mL the maximum yield of ~1 mg/g CLA+CLNA was obtained. In conclusion, the development of a CLA/CLNA-enriched bovine milk through in situ microbial production remains challenging, given the limited number of strains able to produce CLA/CLNA at considerable levels, and because it is difficult to develop a dairy product simultaneously enriched in CLA and CLNA. An in situ strategy has its limitations; nevertheless, this study demonstrates that B. breve DSM 20091 has potential for the development of CLNA-enriched dairy products.