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- Optimized extraction protocols for bioactive antioxidants from commercial seaweeds in Portugal: A comparative study of techniquesPublication . Santos, Francisca; Soares, Cristina; Morais, Stephanie L.; Neves, Cátia; Grosso, Clara; Ramalhosa, Maria João; Vieira, Mónica; Delerue-Matos, Cristina; Domingues, Valentina F.; Vieira, MónicaThis study aimed to optimize the extraction conditions for a valuable source of antioxidants: seaweed. Therefore, ten seaweed samples were subjected to a solid–liquid extraction (SLE), where the extraction conditions (biomass (g): solvent (mL) ratio, temperature, and time) were optimized using response surface methodology (RSM). The seaweeds were also subjected to subcritical water extraction (SWE) (140 and 190 ◦C) and ultrasound-assisted extraction (UAE) (10 and 20 min). The antioxidant capacity of the extracts was determined through the ferric-reducing antioxidant power and the 2,2′ -azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). The total phenolic content revealed the significance of temperature and biomass; solvent ratio parameters in the extraction process with higher conditions generally promoting the release of phenolic compounds. Furthermore, applying RSM allowed for the identification of optimal conditions and the establishment of predictive models that can be valuable in industrial-scale extraction processes. The antioxidant potency composite index (APCI) shows that SWE at 190 ◦C stands out, with E. bicyclis reaching an APCI score of 46.27%. The AGREEprep evaluation showed that UAE is the most sustainable method, achieving the highest score (0.69). The results of this study contribute to the development of efficient and standardized extraction protocols for each seaweed species, allowing for the maximum yield of antioxidants.
- Editorial comments on “Multiarray screening identifies plasma proteins associated with Th17 cell differentiation and viral defense in coincident asthma and obesity”Publication . Rufo, João Cavaleiro; Chauhan, Jitesh; Kalayci, Ömer; Eigenmann, Philippe; Cavaleiro Rufo, JoãoThe clinical associations between asthma and obesity remain poorly understood. The increasing prevalence ofboth conditions occurring may represent a modern clinical paradox. It is unclear whether reduced physical activ-ity in children with asthma leads to obesity, or if asthma-like symptoms in obese children result directly from theassociated excessive abdominal fat, impaired lung function, and heightened Th2 inflammation. Determining theetiology of both diseases and their interconnection is therefore an important research avenue.A recent study has sought to investigate this through a cross-sectional analysis of Australian children, bothwith and without asthma, examining their levels of physical activity. Interestingly, the study found no evidencethat asthma hindered physical activity.1 On the other hand, although most studies have shown obesity is linkedto a higher risk of asthma, the exact mechanism remains unclear. Many studies refer to obesity as an exacerbationfactor for asthma symptoms rather than a direct contributor to the underlying pathophysiological mechanisms ofasthma. 2 This highlights the need for continued research to untangle the complex interplay between these twoconditions.In 2019, a study investigating the associations between exposure to endocrine-disrupting chemicals andchildhood asthma identified a specific pattern of volatile organic compounds that were significantly linked to theearly onset “obese-asthma” phenotype, but not to asthma or obesity independently. 3 This suggests that asthmaand obesity may share common risk factors that trigger disease onset of both conditions during early childhood.Supporting this hypothesis, subsequent research has identified 29 genes associated with the obese-asthma phe-notypes, including GBP5 and SOCS, which further highlights the genetic underpinnings of this dual condition. 4In this issue, Manell et al. offer valuable insights by investigating novel plasma protein biomarkers specificallyassociated with the coexistence of asthma and obesity in an adolescent population. 5 The cross-sectional studyinvolved 390 children and adolescents, aged 10 to 19, who were categorized into four groups: healthy controls,individuals with asthma, individuals with obesity, and those with both obesity and asthma (OA).A proximity extension assay was used to assess the relative plasma concentrations of 113 proteins associatedwith inflammation and immune response. The study identified five plasma proteins—CCL8, IL-33, IL-17C, FGF-23,and CLEC7A—that were significantly and specifically elevated in the OA group compared to controls. However,after adjusting for age, sex, and sIgE levels, only CCL8 and CLEC7A remained significantly elevated. This suggeststhat the high levels observed for IL-33, IL-17C, and FGF-23 in the OA group may be partially attributable to atopy.Drawing on previously published evidence and considering the role of CCL8 in mucosal chemotaxis and Th2inflammation, Manell et al. propose that viral defense at mucosal barriers may play an important role in obesity-related asthma in children and adolescents. 5 While the exact pathophysiological mechanism behind CCL8 over-expression remains unclear, it is noteworthy that prior studies have confirmed no association between CCL8and atopy. 6 This, along with the evidence that CCL8 levels are regulated in obese individuals without asthma,strengthens the argument for this chemokine as a promising biomarker for obese-asthma phenotypes.Additionally, FGF-23, IL-17C, and IL-33, which are linked to mucosal host defense against viral infections andTh17 cell activation, were also regarded as potential biomarkers for concomitant asthma and obesity, though toa lesser extent. 5 Conversely, the elevated levels of CLEC7A in the OA group appear to be additive, reflecting thecombined effects of asthma and obese observed separately.
- Unlocking the functional potential of Mesembryanthemum nodiflorum: Insights into digestibility, safety and intestinal uptakePublication . Pinto, Diana; Vieira, Raquel; Teixeira, Filipa; Sut, Stefania; Vieira, Mónica; Salazar, Miguel; Delerue-Matos, Cristina; Dall’Acqua, Stefano; Rodrigues, Francisca; Vieira, MónicaMesembryanthemum nodiflorum, commonly known as slenderleaf iceplant, is an undervalued edible halophyte. The nutraceutical potential of M. nodiflorum was investigated in the current study by extracting bioactive compounds using ultrasound-assisted extraction (UAE) and assessing the influence of gastrointestinal digestion and intestinal permeability on their bioactive composition. The phenolic and flavonoid contents were the highest in the alcoholic extract, along with exceptional antioxidant/antiradical effects. The gastrointestinal digestion enhances the release and detectability of phenolic compounds and antioxidant activity, with bioaccessibility exceeding 100 %. Additionally, the extracts stimulated antioxidant enzymes and inhibited acetylcholinesterase (AChE), with alcoholic extract showing the highest inhibition (38 %). UPLC-QTOF-MS unveiled high concentrations of glycerophospholipids, tryptophan, and 5,5 ′-dihydroferulic acid. Ethanol was the most effective solvent for extracting bioactive compounds. Through an intestinal co-culture model, the intestinal digest from the alcoholic extract demonstrated notable permeation (66 % for rosmanol, 30 % for Lys-Asp-Tyr, and 15 % for tryptophan). These results highlight the bioactivity and intestinal absorption of M. nodiflorum extracts, repurposing this halophyte as a nutraceutical.
- Enhancement of wound healing in diabetic mice by topical use of a peptide-ionic liquid conjugatePublication . Gomes, Ana; Leal, Ermelindo C.; Ferraz, Ricardo; Calheiros, Daniela; Silva, Jessica da; Gonçalves, Teresa; Teixeira, Inês; Carvalho, Eugénia; Gomes, Paula; Ferraz, RicardoDiabetic foot ulcers (DFU) are one of the most devastating complications of diabetes, with high impact on patient’s quality of life. In worst scenarios, DFU can lead to severe amputation or even death. DFUs are an easy target for microbial pathogens and their effective healing is hampered by the galloping increase of microbial resistance to antibiotics, including from the most prevalent pathogens in DFU, e.g. Staphylococcus aureus. As such, available antibiotics show poor efficacy in the treatment of DFU, leading to a chronic condition that is exacerbated by poor healing rates due to the persistent inflammation, poor oxygenation and low angiogenesis, leading to high risk of ischemia, among other conditions that typically affect patients with diabetes. Our group has recently designed new peptide-based strategies towards the topical treatment of DFU, whereby peptide-ionic liquid conjugates emerged as highly promising agents. One of the best such conjugates, C16-Im-PP4, results from coupling an imidazolium-based ionic liquid with intrinsic antimicrobial activity to the N-terminus of a collagen boosting peptide used in cosmetics, the pentapeptide-4. C16-Im-PP4 showed excellent in vitro properties, namely, wide-spectrum antimicrobial action and collagen-boosting effect on human dermal fibroblasts, prompting the in vivo study here reported. The peptide-ionic liquid conjugate was applied topically on wounds of mice with diabetes. The results show multitargeted actions, at a dose of 1 µg/wound including: i) anti-inflammatory; ii) antioxidant; iii) pro-collagenic; vi) pro-angiogenic; v) antimicrobial; and vi) improved wound maturation effects. Altogether, these results identify this technology as a novel topical treatment for DFU.
- Development of a sustainable biosensor to detect respiratory infectious diseasesPublication . Nascimento, Ana Margarida; Abreu, Cristina; Silva, M.; Leite, B.; Rouly, S.; Abreu, M. J.; Ferraz, Ricardo; Costa, M.; Prudêncio, Cristina; Parente, E.; Vieira, Mónica; Ferraz, Ricardo; Vieira, Mónica; Prudêncio, CristinaThe Covid-19 pandemic brought the need to use social masks to prevent the spread of the SARS-CoV-2 virus. However, no reliable and fast method were yet established to detect viral particles and to improve the protective ability of social masks. Through color changes, colorimetric biosensors can be used as a rapid and easily approach to detect virus. Gold nanoparticles (AuNP) are known to have excellent optical properties and huge research potential. The new SARS-CoV-2 has the ability of entering human body cells, namely through a second pathway of entry – the sialic acid (SA) receptor. In order to respond to the emergency and to contribute to the diminishing of the spread of SAR-CoV-2, we developed a colorimetric biosensor based on the functionalization AuNP by sialic acid (SA) (SA-AuNP), as a new and effective textile coating layer, to provide a direct indication of the protective capacity of social masks. To do that, AuNPs (10 nm) were functionalized with SA (SA-AuNP), in three different concentrations (50-50, 30-70 and 20-80, respectively) to select the optimal concentration for respiratory virus detection. Fourier-transform infrared spectroscopy (FTIR) and Scanning Electron Microscope with a Transmission Detector (STEM) analyses confirmed SA-AuNPs binding. FTIR results showed a well-established bond, through matches of peaks of SA-AuNPs. Bindings between the compounds were more evident in 50-50 concentration of SA-AuNP. In the 30-70 SA-AuNP the STEM images show some superposition of the nanoparticles and not so evident binding, as in the 20-80 concentration. Still, between these last two concentrations, the 30-70 is the one that shows the best results since it is visible some circular points larger than the others. To achieve the goal, the concentrations 30-70 and 50-50 of SA-AuNP were impregnated (Textile Foulard) in two substrates of different compositions, a cellulosic and a synthetic one. However, in this technique there are many parameters, such as drying time and temperature, which were varied to understand which the best procedure was to obtain the biosensor.
- Nature-based hydrogels combined with nanoparticles for bone regenerationPublication . Fernandes, Margarida; Vieira, Mónica; Peixoto, Daniela; Alves, Natália M.; Vieira, MónicaBone is a calcified tissue composed of 60% inorganic compounds, 30% organic compounds, and 10% water. Bone exhibits an intrinsic regenerative capacity, enabling it to heal after fractures or adapt during growth. However, in cases of severe injury or extensive tissue loss, this regenerative capacity becomes insufficient, often necessitating bone graft surgeries using autografts or allografts. Conventional grafting approaches present several limitations, driving the development of alternative strategies in tissue engineering. The system of hydrogel–nanoparticles (NPs) represents a new class of biomaterials designed to combine the advantages of both materials while mitigating their drawbacks. This review focuses on a combination of nature-based hydrogels with different types of nanoparticles and discusses their potential applications in bone regeneration.
- Betulinic acid and obesity-related disordersPublication . Azevedo, Lara; Ferraz, Ricardo; Vieira, Mónica; Prudêncio, Cristina; Fernandes, Sílvia; Ferraz, Ricardo; Almeida Vieira, Mónica Andreia; Prudêncio, Cristina; Fernandes, SílviaThe obesity epidemic is not just a health issue, it is increasingly driving a shift in the prevalence of chronic diseases, affecting 890 million adults and straining healthcare systems worldwide. Conditions such as type 2 diabetes mellitus, cardiovascular diseases, non-alcoholic fatty liver disease, and various cancer types are closely tied to this growing crisis. Betulinic acid has anti-inflammatory, antioxidant and anti-cancer properties and modulates key metabolic pathways such as NF-κB and AMPK signaling. This compound improves insulin sensitivity, reduces hepatic steatosis, mitigates the progression of atherosclerosis and fibrosis, and suppresses inflammatory responses, which are important in treating those obesity-related disorders. Additionally, betulinic acid use in cancer treatment has been explored due to its potential in angiogenesis and metastasis inhibition and promotion of apoptosis. This review spotlights the therapeutic potential of the natural compound betulinic acid in processes such as insulin sensitivity, glucose and lipid metabolism, adiposity, inflammation, oxidative stress, intestinal microbiota, and other mechanisms underlying different obesity-related disorders. Overall, besides strong therapeutic potential of betulinic acid, described limitations such as poor aqueous solubility, limited bioavailability, production and extraction have resulted in scarce clinical data making it premature to draw definitive conclusions regarding its application in clinical practice.
- Environmental and food safety assessment of pre-harvest activities in local small-scale fruit and vegetable farms in northwest Portugal: Hazard identification and compliance with good agricultural practices (GAPs)Publication . Macieira, Ariana; Fernandes, Virgínia Cruz; Brandão, Teresa R. S.; Delerue-Matos, Cristina; Teixeira, Paula; Fernandes, VirgíniaThe popularity of small-scale and local fruit and vegetable production has increased in recent years due to perceived economic, environmental, and social benefits. However, these operations face contamination risks that both consumers and small-scale producers may underestimate. The present study aimed to assess the microbiological and chemical hazards on fruit, vegetables, soil, and water samples from small-scale farms in north-western Portugal during pre-harvest activities. Additionally, the study investigated farmers’ non-compliance with food safety regulations and good agricultural practices (GAPs), exploring how their behaviour might contribute to the identified hazards. A before-and-after analysis of non-compliant behaviours was conducted to determine the impact of training on improving food safety practices. The analysis identified the presence of pathogenic bacteria, pesticides, flame retardant residues, nitrates, and heavy metals. Lead (Pb) concentrations exceeded EU limits in organic carrots from one producer (0.156 ± 0.043 mg/kg) and in chard from another (0.450 ± 0.126 mg/kg). Cadmium (Cd) levels were also above regulatory thresholds in bell peppers (0.023 ± 0.009 mg/kg) and organic tomatoes (0.026 ± 0.015 mg/kg) from two different producers. Elevated levels of heavy metals were detected in irrigation water from two sites, with zinc (Zn) at 0.2503 ± 0.0075 mg/L and Pb at 0.0218 ± 0.0073 mg/L. Among food samples, the most prevalent microorganisms were Pseudomonas spp. (88.2%), Bacillus cereus (76.5%), and aerobic mesophilic bacteria (100%). Phosphorus flame retardants (PFRs), particularly tris(2-butoxyethyl) phosphate (TBEP), were detected in all food and soil samples. Some EU-banned pesticides were detected in food and soil samples, but at levels below the maximum residue limits (MRLs). Chlorpyrifos (35.3%) and p,p’-DDD (23.5%) were the most detected pesticides in food samples. After the training, GAP behaviour improved, particularly that related to hygiene. However, issues related to record-keeping and soil and water analyses persisted, indicating ongoing challenges in achieving full compliance.
- Unraveling the nutraceutical potential of Salicornia ramosissima by-product – impact of gastrointestinal digestion and intestinal permeability on in vitro bioactivityPublication . Pinto, Diana; Santos, Inês; Delerue-Matos, Cristina; Teixeira, Filipa; Sut, Stefania; Dall’Acqua, Stefano; Vieira, Mónica; Rodrigues, Francisca; Almeida Vieira, Mónica AndreiaSalicornia ramosissima by-product (SP) is an underexploited antioxidant-rich by-product. This study explored the phytochemical profile, bioaccessibility, and biological activity of SP before and after extraction (SBE and SAE, respectively) upon gastrointestinal simulated digestion and intestinal permeability. The phenolic and flavonoid concentrations increased during digestion, reaching bioaccessibility rates above 95 % for both SBE and SAE. Promising antioxidant/antiradical properties and neuroprotective effects were attested upon digestion. Regarding the phytochemical profile, 17 compounds were identified, including (di)caffeoylquinic acids, gallocatechin, and triterpenoid saponins. The intestinal absorption of bioactive compounds from SAE and SBE intestinal digests was proven through a Caco-2/HT29-MTX cells co-culture model, with 4-caffeoylquinic acid (34.84 %) and 4,5-dicaffeoylquinic acid (26.73 %) reaching the highest permeation rates after 4 h, respectively, for SAE and SBE. These findings support the harnessing of SP as a promising functional and nutraceutical ingredient rich in pro-healthy compounds with proven bioactivity upon in vitro digestion and intestinal permeation.
- CD5L is upregulated upon infection with Mycobacterium tuberculosis with no effect on disease progressionPublication . Cardoso, Marcos S.; Gonçalves, Rute; Oliveira, Liliana; Silvério, Diogo; Téllez, Erica; Paul, Tony; Sarrias, Maria Rosa; Carmo, Alexandre M.; Saraiva, MargaridaTuberculosis (TB) alone caused over a billion deaths in the last 200 years, making it one of the deadliest diseases to humankind. Understanding the immune mechanisms underlying protection or pathology in TB is key to uncover the much needed innovative approaches to tackle TB. The scavenger receptor cysteine-rich molecule CD5 antigen-like (CD5L) has been associated with TB, but whether and how CD5L shapes the immune response during the course of disease remains poorly understood. Here, we show an upregulation of CD5L in circulation and at the site of infection in C57BL/6 Mycobacterium tuberculosis-infected mice. To investigate the role of CD5L in TB, we studied the progression of M. tuberculosis aerosol infection in a recently described genetically engineered mouse model lacking CD5L. Despite the increase of CD5L during infection of wild-type mice, absence of CD5L did not impact bacterial burden, histopathology or survival of infected mice. Absence of CD5L associated with a modest increase in the numbers of CD4+ T cells and the expression of IFN-γ in the lungs of infected mice, with no major effect in overall immune cell dynamics. Collectively, this study confirms CD5L as a potential diagnostic biomarker to TB, showing no discernible impact on the outcome of the infection.