Neuroprotective effects of anthocyanins are mediated by gut microbiota

The microbes that collectively inhabit the gut, the gut microbiota, constitute the largest and most diverse community in the body. Besides having an important role in the regulation of host energy metabolism, the gut microbiota can also influence neurodevelopment, modulate behavior and contribute to the development of neurological disorders. High-fat (HF) diets are thought to disrupt the profile of the gut microbiota in a manner that may contribute to the neuroinflammation and neurobehavioral changes observed in obesity. Accordingly, we hypothesized that by preventing HF-diet induced dysbiosis it is possible to prevent neuroinflammation and the consequent neurological disorders.info:eu-repo/semantics/publishedVersio

Photochemistry of 5-Hydroxy-4'-Dimethylaminoflavylium in the presence of SDS micelles. The role of metastable states of flavylium cation-quinoidal base and trans-chalcones

UIDB/50006/2020 UIDP/50006/2020 PTDC/QUI-OUT/29013/2017 SFRH/BD/143309/2019 SFRH/BD/146549/2019 MEX/Ref. 288188 IF/00225/2015The multistate of species originated by the compound 5-hydroxy-4′-dimethylaminoflavylium was studied in the presence of sodium dodecyl sulfate micelles 0.1 M. A series of pH jumps obtained by addition of base to the equilibrated solutions of the flavylium cation results in a metastable equilibrium between the flavylium cation and the quinoidal base with pKa = 7.6. In neutral to moderately basic medium, only at 60 °C and after 5 days a new distribution involving the flavylium cation and trans-chalcones is achieved. On the other hand, the anionic trans-chalcone can be formed in few minutes in very basic medium at room temperature and from this, another meta-stable state constituted by protonated, neutral and anionic trans-chalcones, pKCt+/Ct = 2.6 and pKCt/Ct- = 10.7 is reached. The equilibrium is apparently attained between flavylium cation, neutral and anionic trans-chalcones respectively for pKAH+/Ct = 4.1 and pKCt/Ct- = 10.7. Irradiation of the neutral (stable or metastable) and protonated (meta-stable) trans-chalcones yields to the appearance of the quinoidal base or the flavylium cation in an extended pH region 1 < pH < 10. The peculiar properties of this flavylium based photochromic system are explained by means of an energy level diagram where cis-chalcone and hemiketal lay above the quinoidal base.authorsversionpublishe

“Clicking” an ionic liquid to a potent antimicrobial peptide: on the route towards improved stability

A covalent conjugate between an antibacterial ionic liquid and an antimicrobial peptide was produced via “click” chemistry, and found to retain the parent peptide’s activity against multidrug-resistant clinical isolates of Gram-negative bacteria, and antibiofilm action on a resistant clinical isolate of Klebsiella pneumoniae, while exhibiting much improved stability towards tyrosinase-mediated modifications. This unprecedented communication is a prelude for the promise held by ionic liquids -based approaches as tools to improve the action of bioactive peptides.info:eu-repo/semantics/publishedVersio

Turning a Collagenesis-Inducing Peptide Into a Potent Antibacterial and Antibiofilm Agent Against Multidrug-Resistant Gram-Negative Bacteria

Antimicrobial resistance is becoming one the most serious health threats worldwide, as it not only hampers effective treatment of infectious diseases using current antibiotics, but also increases the risks of medical procedures like surgery, transplantation, bone and dental implantation, chemotherapy, or chronic wound management. To date, there are no effective measures to tackle life-threatening nosocomial infections caused by multidrug resistant bacterial species, of which Gram-negative species within the so-called "ESKAPE" pathogens are the most worrisome. Many such bacteria are frequently isolated from severely infected skin lesions such as diabetic foot ulcers (DFU). In this connection, we are pursuing new peptide constructs encompassing antimicrobial and collagenesis-inducing motifs, to tackle skin and soft tissue infections by exerting a dual effect: antimicrobial protection and faster healing of the wound. This produced peptide 3.1-PP4 showed MIC values as low as 1.0 and 2.1 μM against Escherichia coli and Pseudomonas aeruginosa, respectively, and low toxicity to HFF-1 human fibroblasts. Remarkably, the peptide was also potent against multidrug-resistant isolates of Klebsiella pneumoniae, E. coli, and P. aeruginosa (MIC values between 0.5 and 4.1 μM), and hampered the formation of/disaggregated K. pneumoniae biofilms of resistant clinical isolates. Moreover, this notable hybrid peptide retained the collagenesis-inducing behavior of the reference cosmeceutical peptide C16-PP4 ("Matrixyl"). In conclusion, 3.1-PP4 is a highly promising lead toward development of a topical treatment for severely infected skin injuries.info:eu-repo/semantics/publishedVersio

Insights into the development of grapefruit nutraceutical powder by spray drying: physical characterization, chemical composition and 3D intestinal permeability

The development of functional and nutraceutical foods comes from a greater awareness of the relationship between food and health by consumers. In recent years, the idea of purifying and encapsulating bioactive compounds through techniques such as spray drying has been well received by the food industry. The development and characterization of a grapefruit (Citrus paradisi) nutraceutical powder obtained by spray drying is of great interest owing to the different bioactive compounds and the potential health effects.Francisca Rodrigues is thankful for her postdoc research grant fromthe project Operação NORTE-01-0145-FEDER-000011. Iva Fernan-des is grateful for the Post-Doctoral Grant SFRH/BPD/86173/2012from the Foundation for Science and Technology. This workreceived financial support from the European Union (FEDERfunds through COMPETE), under the Partnership AgreementPT2020, and National Funds (FCT, Foundation for Scienceand Technology) through project LAQV/UID/QUI/50006/2013and NORTE-07-0124-FEDER-000069 – Food Science. The authorswish also to thank the Ministerio de Economía y Competitividadand FEDER for the financial support given through the Project AGL2012-39103.info:eu-repo/semantics/publishedVersio

Behind the Scenes of Anthocyanins-From the Health Benefits to Potential Applications in Food, Pharmaceutical and Cosmetic Fields

Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains. The pigments' stability and colours are influenced mainly by pH but also by structure, temperature, and light. The colour-stabilizing mechanisms of plants are determined by inter- and intramolecular co-pigmentation and metal complexation, driven by van der Waals, π-π stacking, hydrogen bonding, and metal-ligand interactions. This group of flavonoids is well-known to have potent anti-inflammatory and antioxidant effects, which explains the biological effects associated with them. Therefore, this review provides an overview of the role of anthocyanins as natural colorants, showing they are less harmful than conventional colorants, with several technological potential applications in different industrial fields, namely in the textile and food industries, as well as in the development of photosensitizers for dye-sensitized solar cells, as new photosensitizers in photodynamic therapy, pharmaceuticals, and in the cosmetic industry, mainly on the formulation of skin care formulations, sunscreen filters, nail colorants, skin & hair cleansing products, amongst others. In addition, we will unveil some of the latest studies about the health benefits of anthocyanins, mainly focusing on the protection against the most prevalent human diseases mediated by oxidative stress, namely cardiovascular and neurodegenerative diseases, cancer, and diabetes. The contribution of anthocyanins to visual health is also very relevant and will be briefly explored

Disclosure of a promising lead to tackle complicated skin and skin structure infections: antimicrobial and antibiofilm actions of peptide PP4-3.1

Efficient antibiotics are being exhausted, which compromises the treatment of infections, including complicated skin and skin structure infections (cSSTI) often associated with multidrug resistant (MDR) bacteria, methicillin-resistant S. aureus (MRSA) being the most prevalent. Antimicrobial peptides (AMP) are being increasingly regarded as the new hope for the post-antibiotic era. Thus, future management of cSSTI may include use of peptides that, on the one hand, behave as AMP and, on the other, are able to promote fast and correct skin rebuilding. As such, we combined the well-known cosmeceutical pentapeptide-4 (PP4), devoid of antimicrobial action but possessing collagenesis-boosting properties, with the AMP 3.1, to afford the chimeric peptide PP4-3.1. We further produced its N-methyl imidazole derivative, MeIm-PP4-3.1. Both peptide-based constructs were evaluated in vitro against Gram-negative bacteria, Gram-positive bacteria, and Candida spp. fungi. Additionally, the antibiofilm activity, the toxicity to human keratinocytes, and the activity against S. aureus in simulated wound fluid (SWF) were assessed. The chimeric peptide PP4-3.1 stood out for its potent activity against Gram-positive and Gram-negative bacteria, including against MDR clinical isolates (0.8 ≤ MIC ≤ 5.7 µM), both in planktonic form and in biofilm matrix. The peptide was also active against three clinically relevant species of Candida fungi, with an overall performance superior to that of fluconazole. Altogether, data reveal that PP4-3.1 is as a promising lead for the future development of new topical treatments for severe skin infections.info:eu-repo/semantics/publishedVersio

Bacteria-responsive multilayer coatings comprising polycationic nanospheres for bacteria biofilm prevention on urinary catheters

This work reports on the development of infection-preventive coatings on silicone urinary catheters that contain in their structure and release on demand antibacterial polycationic nanospheres. Polycationic aminocellulose conjugate was first sonochemically processed into nanospheres to improve its antibacterial potential compared to the bulk conjugate in solution (ACSol). Afterwards the processed aminocellulose nanospheres (ACNSs) were combined with the hyaluronic acid (HA) polyanion to build a layer-by-layer construct on silicone surfaces. Although the coating deposition was more effective when HA was coupled with ACSol than with ACNSs, the ACNSs-based coatings were thicker and displayed smoother surfaces due to the embedment of intact nanospheres. The antibacterial effect of the ACNSs multilayers was by 40 % higher compared to the ACSol coatings. This fact was further translated into more effective prevention of Pseudomonas aeruginosa biofilm formation. The coatings were stable in absence of bacteria, whereas their disassembling occurred gradually during incubation with Pseudomonas aeruginosa, and thus eradicate the biofilm upon release of antibacterial agents. Only 5 bilayers of HA/ACNSs were sufficient to prevent the biofilm formation, in contrast to the 10 bilayers of ACSol required to achieve the same effect. The antibiofilm efficiency of (HA/ACNSs)10 multilayer construct built on a Foley catheter was additionally validated under dynamic conditions using a model of catheterized bladder in which the biofilm was grown during seven days.M.M.F. acknowledges the support of the European Commissionunder the Marie Curie Intra-European Fellowship (IEF) Program (Grant Agreement ‘‘NanoQuench” FP7-331416)

Effectiveness and long-term retention of anti-tumour necrosis factor treatment in juvenile and adult patients with juvenile idiopathic arthritis: data from Reuma.pt

Methods. We prospectively collected patient and disease characteristics from patients with JIA who started biological therapy. Adverse events were collected during the follow-up period. Predictors of response at 1 year and drug retention rates were assessed at 4 years of treatment for the first biologic agent.Results. A total of 812 JIA patients [65% females, mean age at JIA onset 6.9 years (s.d. 4.7)], 227 received biologic therapy; 205 patients (90.3%) were treated with an anti-TNF as the first biologic. All the parameters used to evaluate disease activity, namely number of active joints, ESR and Childhood HAQ/HAQ, decreased significantly at 6 months and 1 year of treatment. The mean reduction in Juvenile Disease Activity Score 10 (JADAS10) after 1 year of treatment was 10.4 (s.d. 7.4). According to the definition of improvement using the JADAS10 score, 83.3% respond to biologic therapy after 1 year. Fourteen patients discontinued biologic therapies due to adverse events. Retention rates were 92.9% at 1 year, 85.5% at 2 years, 78.4% at 3 years and 68.1% at 4 years of treatment. Among all JIA subtypes, only concomitant therapy with corticosteroids was found to be univariately associated with withdrawal of biologic treatment (P = 0.016).Conclusion. Biologic therapies seem effective and safe in patients with JIA. In addition, the retention rates for the first biologic agent are high throughout 4 years