LSRE-LCM - Artigos em Revistas Nacionais e de Circulação Internacional
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- Are There Lipid Membrane-Domain Subtypes in Neurons with Different Roles in Calcium Signaling?Publication . Samhan-Arias, Alejandro K.; Poejo, Joana; Marques-da-Silva, Dorinda; Martínez-Costa, Oscar H.; Gutierrez-Merino, CarlosLipid membrane nanodomains or lipid rafts are 10–200 nm diameter size cholesterol- and sphingolipid-enriched domains of the plasma membrane, gathering many proteins with different roles. Isolation and characterization of plasma membrane proteins by differential centrifugation and proteomic studies have revealed a remarkable diversity of proteins in these domains. The limited size of the lipid membrane nanodomain challenges the simple possibility that all of them can coexist within the same lipid membrane domain. As caveolin-1, flotillin isoforms and gangliosides are currently used as neuronal lipid membrane nanodomain markers, we first analyzed the structural features of these components forming nanodomains at the plasma membrane since they are relevant for building supramolecular complexes constituted by these molecular signatures. Among the proteins associated with neuronal lipid membrane nanodomains, there are a large number of proteins that play major roles in calcium signaling, such as ionotropic and metabotropic receptors for neurotransmitters, calcium channels, and calcium pumps. This review highlights a large variation between the calcium signaling proteins that have been reported to be associated with isolated caveolin-1 and flotillin-lipid membrane nanodomains. Since these calcium signaling proteins are scattered in different locations of the neuronal plasma membrane, i.e., in presynapses, postsynapses, axonal or dendritic trees, or in the neuronal soma, our analysis suggests that different lipid membrane-domain subtypes should exist in neurons. Furthermore, we conclude that classification of lipid membrane domains by their content in calcium signaling proteins sheds light on the roles of these domains for neuronal activities that are dependent upon the intracellular calcium concentration. Some examples described in this review include the synaptic and metabolic activity, secretion of neurotransmitters and neuromodulators, neuronal excitability (long-term potentiation and long-term depression), axonal and dendritic growth but also neuronal cell survival and death.
- Cardiolipin Membranes Promote Cytochrome c Transformation of Polycyclic Aromatic Hydrocarbons and Their In Vivo MetabolitesPublication . Lopes, João; Marques-da-Silva, Dorinda; Videira, Paula A.; Samhan-Arias, Alejandro K.; Lagoa, RicardoThe catalytic properties of cytochrome c (Cc) have captured great interest in respect to mitochondrial physiology and apoptosis, and hold potential for novel enzymatic bioremediation systems. Nevertheless, its contribution to the metabolism of environmental toxicants remains unstudied. Human exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with impactful diseases, and animal models have unveiled concerning signs of PAHs’ toxicity to mitochondria. In this work, a series of eight PAHs with ionization potentials between 7.2 and 8.1 eV were used to challenge the catalytic ability of Cc and to evaluate the effect of vesicles containing cardiolipin mimicking mitochondrial membranes activating the peroxidase activity of Cc. With moderate levels of H2O2 and at pH 7.0, Cc catalyzed the oxidation of toxic PAHs, such as benzo[a]pyrene, anthracene, and benzo[a]anthracene, and the cardiolipin-containing membranes clearly increased the PAH conversions. Our results also demonstrate for the first time that Cc and Cc–cardiolipin complexes efficiently transformed the PAH metabolites 2-hydroxynaphthalene and 1-hydroxypyrene. In comparison to horseradish peroxidase, Cc was shown to reach more potent oxidizing states and react with PAHs with ionization potentials up to 7.70 eV, including pyrene and acenaphthene. Spectral assays indicated that anthracene binds to Cc, and docking simulations proposed possible binding sites positioning anthracene for oxidation. The results give support to the participation of Cc in the metabolism of PAHs, especially in mitochondria, and encourage further investigation of the molecular interaction between PAHs and Cc.
- Complexation and DFT studies of lower rim hexahomotrioxacalix[3]arene derivatives bearing pyridyl groups with transition and heavy metal cations. Cone versus partial cone conformationPublication . Marcos, Paula M.; Teixeira, Filipa A.; Segurado, Manuel A. P.; Ascenso, José R.; Bernardino, Raul; Peter J. Cragg; Sylvia Michel; Véronique Hubscher-Bruder; Françoise Arnaud-NeuThe binding of representative alkali, alkaline earth, transition and heavymetal cations by 2-pyridylmethoxy derivatives (1b, in cone and partial cone conformations) of p-tert-butylhexahomotrioxacalix[3]arene was studied. Binding was assessed by extraction studies of the metal picrates from water into dichloromethane and by stability constant measurements in acetonitrile and methanol, using spectrophotometric and potentiometric techniques. Microcalorimetric studies of some selected complexes in acetonitrile were performed, as well as proton NMR titrations. Computational methods (density functional theory calculations) were also employed to complement the NMR data. The results are compared with those obtained with the dihomooxacalix[4]arene 2b and the calix[4]arene 3b derivative analogues. Partial cone-1b is the best extractant for transition and heavy metal cations. Both conformers of 1b exhibit very high stability constants for soft and intermediate cations Pb2+, Cd2+, Hg2+, Zn2+ and Ni2+, with cone-1b the strongest binder (ML, log b ≥7) and partial cone-1b the most selective. Both derivatives show a slight preference for Na+. Besides the formation of ML complexes, ML2 and M2L species were also observed. The former complexes were, in general, formed with the transition and heavy metal cations, whereas the latter were obtained with Ag+ and Hg2+ and partial cone-1b. In most cases, these species were corroborated by the proton NMR and density functional theory studies.
- Enhancing human gut health: Global innovations in dysbiosis managementPublication . Lagoa, Ricardo; Reda El Boukhari; Maima Matin; Latifa Bouissane; Michał Ławiński; Oleh Lushchak; Rajeev K. Singla; Michel‐Edwar Mickael; Jordi Mayneris‐Perxachs; Maria Eleni Grafakou; Shuhua Xu; Bowen Liu; Jiayi Guan; Andrzej Półtorak; Arkadiusz Szpicer; Agnieszka Wierzbicka; Nikolay T. Tzvetkov; Maciej Banach; Jarosław Olav Horbańczuk; Artur Jóźwik; Marco Cascella; Bairong Shen; Vasil Radoslavov Pirgozliev; Dongdong Wang; Olena Litvinova; Olga Adamska; Agnieszka Kamińska; Marcin Łapiński; Artur Stolarczyk; Ioana Berindan‐Neagoe; Luigi Milella; Andy Wai Kan Yeung; Prashanth Suravajhala; Anupam Bishayee; Ronan Lordan; Laszlo Barna Iantovics; Monika Michalczuk; Jivko Stoyanov; A. Douglas Kinghorn; Banaz Jalil; Wolfram Weckwerth; Bey Hing Goh; Meng‐Yao Li; Gyaneshwer Chaubey; Gian Luigi Russo; Sara Frazzini; Luciana Rossi; Maurizio Battino; Wei Jia; Qi Su; Xiaoqiang Ma; Judith M. Rollinger; Simon K.‐M. R. Rittmann; Helen Sheridan; John J. Walsh; Gérard Lizard; Tomasz M. Karpiński; Ana Sanches Silva; Jakub Piwowarski; Liwei Xie; Tai‐Ping Fan; Francesca Giampieri; Adil El Midaoui; Ka‐Hing Wong; Ren‐You Gan; Ahmed Fatimi; Atanas G. AtanasovTo the Editor, The gut microbiota represents all the microorganisms, mainly bacteria, that coexist in the digestive system and are mostly beneficial. In adulthood, the gut microbiota composition, which varies from person to person, generally remains stable with a particular density in each part of the digestive system. However, a microbial community imbalance within the body, particularly in the gut, is sometimes observed, causing dysbiosis characterized by reduced microbial diversity, loss of beneficial bacteria, and increased pathogenic microorganisms. [...]
- Health-promoting and medicinal properties of Zingiberaceae family plants: A minireview with a special focus on galangal, turmeric, cardamom, and gingerPublication . Lagoa, Ricardo; Maima Matin; Rajeev K. Singla; Artur Jóźwik; Jarosław Olav Horbańczuk; Natalia Ksepka; Kamil Wysocki; Thadiyan Parambil Ijinu; Neenthamadathil Mohandas Krishnakumar; Sreejith Pongillyathundiyil Sasidharan; Ifeoma C. Ezenyi; John Igoli; Fabio Fusi; Sara Frazzini; Luciana Rossi; Michel-Edwar Mickael; Abhishek Joshi; Olga Adamska; Artur Stolarczyk; Esra Capanoglu; Deniz Gunal-Koroglu; Shi-Hui Cheng; Omar M. Atrooz; Kiran Kharat; Ibrahim M. Abu-Reidah; Neeraj Rani; Atul Kabra; Ruchika Kabra; Dama Sreedhar Preethidan; Prathyusha Surendran; Emad Mohamed Abdallah; Seetha Harilal; Rajesh Kumar; Syed Abidullah; Hemanth Kumar Boyina; Vimal Arora; Prasanna Srinivasan Ramalingam; Sujatha Elangovan; Sivakumar Arumugam; Tanveer Alam; Edlira Aruci; Elena González-Burgos; Isabel Ureña-Vacas; Visitación López-Miranda; Esperanza Herradón; Rupesh Kumar Gautam; Rajat Goyal; Shah Alam Khan; Logesh Rajan; Joel Ojogbane Onoja; Sharad Vats; Akinleye Akinrinde; Smith B. Babiaka; Conrad V. Simoben; Doris E. Enow; Kennedy O. Abuga; Priti Talwar; Palaniyandi Ravanan; Reda El Boukhari; Ahmed Fatimi; Fabien Schultz; Ren-You Gan; Jean Noël Nyemb; Gaetan Bayiha Ba Njock; Constant Anatole Pieme; Goh Bey Hing; Nikolay T. Tzvetkov; Farhan Bin Matin; Antonello Santini; Jaya Arora; Aswathy Chankaramkandath Vasu; Suraj Kadunganattil; Abeer Essam Noman; Luay M Alsubhi; Indra Lasmana Tarigan; Shafaat Yar Khan; Ali Zarrabi; Hefa Mangzira Kemung; Kavitha Raj Varadaraju; Tomasz M. Karpiński; Md. Mohaiminul Islam; Shaikh Jamal Uddin; Carmela Fimognari; Hari Prasad Devkota; Ivana Carev; Dongdong Wang; Kenneth Anchang Yongabi; Luther Bob Mbeku; Sohini Chakraborty; Sourav S. Patnaik; Shanmugam Thangapandiyan; Bikash Baral; Siva Sai Chandragiri; Eliana B. Souto; Gérard Lizard; Fatiha Brahmi; Farid Khallouki; Adil El Midaoui; Ronan Lordan; Anupam Bishayee; Meng-Yao Li; Monika Szymańska-Czerwińska; Krzysztof Niemczuk; Manik Chandra Shill; Michał Ławiński; Oleh Lushchak; Iwona Wojtasik-Kalinowska; Agnieszka Wierzbicka; Thomas Jakschitz; Mathew Dan; Imen Ghzaiel; Leila Rezig; Anne Vejux; Amira Zarrouk; Ahmad Ali; Andy Wai Kan Yeung; Günther K. Bonn; Bairong Shen; Atanas G. AtanasovThe Zingiberaceae family, including among others, galangal (Alpinia galanga), turmeric (Curcuma longa), cardamom (Elettaria cardamomum), and ginger (Zingiber officinale), has been widely used in traditional medicine and culinary practices worldwide due to its diverse health-promoting properties. This mini-review aims to provide a concise overview of Zingiberaceae species’ medicinal potential and identify key areas for further research to facilitate their integration into modern medicine. Herein we summarize the existing research on the pharmacological activities of these species, with a focus on their antioxidant, anti-inflammatory, antimicrobial, anticancer, cardiovascular, digestive, and metabolic effects. Aside from the reported biological effects of traditional formulations and phytopharmaceutical preparations, emphasis is given to the primary bioactive compounds identified in these plants including diverse phenolics, terpenes, and various other secondary metabolites. Mechanisms contributing to therapeutic benefits. Moreover, highlighted is the promise of these plants for future development of drugs and nutraceuticals despite current challenges, particularly bioavailability issues and the need for more clinical studies.
- Humic acid aggregates with laccase and decreases the performance of the enzyme catalytic systems through various mechanismsPublication . Lopes, João; Marques-da-Silva, Dorinda; Peralta, Cláudia; Rodrigues, Joaquim Rui; Vaz, Daniela; Lagoa, RicardoLaccases are among the best-rated enzymes for industrial and environmental applications, yet their use in bioremediation is limited by interference from environmental components like humic acid (HA). This study evaluated HA impact on the oxidation of 2,2 ′-azino-bis-(3-ethylbenzothiazoline-6-sulphonate (ABTS) and two model pollutants — anthracene and methyl orange — by laccase( mediator) systems. HA consistently diminished conversion rates, with EC50 values between 5 and 51 mg/L suggesting diverse inhibitory mechanisms. We investigated potential mechanisms including substrate sequestration, radical quenching, and chelation of laccase coppers by HA. Incubations with free and immobilized HA showed that adsorption can impede anthracene degradation, at least at high concentrations, but not methyl orange. Using chemically generated ABTS radical and azide-blocked enzyme, it was demonstrated that HA scavenges free radicals produced by laccase, though this alone did not fully explain the observed interference with catalysis. Further assays with metal chelator and added copper or calcium ruled out HA binding to the laccase metal centers. Instead, data from molecular docking, f luorescence, light scattering, and microscopy revealed that HA forms micrometer-scale aggregates with laccase that encapsulate the enzyme. This newly identified mechanism likely applies broadly to laccase-based systems and must be considered in applications involving aqueous media containing humic substances.
- Influence of commensal bacteria on the proteolytic and antigenic profiles of INFOGEST-like digested wheat gliadinPublication . Pereira-Costa, Flávio; Domingues, Vanessa S.; Roque, Ana; Almeida, Zaida L.; Cruz, Pedro F.; Cordeiro, Rachel; Trindade, Daniela; Moura, Carla; Melo, Joana B.; Pereira, Sónia G.; Vaz, Daniela C.Introduction: Celiac disease (CeD) is a chronic autoimmune enteropathy developed by genetically predisposed individuals when exposed to gluten. Gluten gliadins, along with gut microbiota, may influence CeD onset and progression through mechanisms that remain unclear. Methods: Gliadin-degrading bacterial isolates obtained from CeD patients, and their 1st-degree relatives’ stool and blood were identified (Bacillus tropicus, Enterococcus faecalis, Micrococcus sp., Cronobacter sakazakii, Pseudomonas aeruginosa, and Serratia marcescens) and used in an INFOGEST-like protocol to simulate gliadin digestion after 4 h (digested gliadin, d-gliadin). The d-gliadin digesta were analyzed by fast protein liquid chromatography (FPLC), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), fluorescence spectroscopy, and polyclonal and monoclonal (R5 and G12) enzyme-linked immunosorbent assays (ELISA). Results and discussion: In the absence of the bacterial isolates, gliadin is poorly digested and self-assembles within 1 day into intermediate and large protein oligomers/aggregates, enriched in β-sheet structure (FTIR amide I band between 1,600 and 1,700 cm−1) and able to bind thioflavin T and Congo red. Conversely, in the presence of the bacterial isolates, gliadin is further digested, leading to an increase in protein fragments. After 4 h, the P. aeruginosa, C. sakazakii, and B. tropicus d-gliadin digesta presented a mixture of d-gliadin peptides and aggregates that showed higher antigenicity (associated with the exposure of the 5-amino acid QQPFP and 6-amino acid QPQLPY epitopes, present in the 25-mer and 33-mer, respectively) than control digestions (without bacteria), while E. faecalis led to lower antigenicity. In turn, within 24 h of incubation, all bacterial isolates led to the formation of undigested material with lower antigenicity, either due to fewer 33-mers and 25-mers in solution, or to fragment aggregation into amorphous material, not exposing antigenic sequences. Hence, intestinal flora may enhance or diminish the antigenicity of gliadin, thereby modulating the immunogenic response to gliadin/gluten.
- Metal alginates for polyphenol delivery systems: Studies on crosslinking ions and easy-to-use patches for release of protective flavonoids in skinPublication . Silva, João; Vanat, Pavlo; Marques da Silva, Dorinda; Rodrigues, Joaquim Rui; Lagoa, RicardoIncorporation of bioactive natural compounds like polyphenols is an attractive approach for enhanced functionalities of biomaterials. In particular flavonoids have important pharmacological activities, and controlled release systems may be instrumental to realize the full potential of these phytochemicals. Alginate presents interesting attributes for dermal and other biomaterial applications, and studies were carried here to support the development of polyphenol-loaded alginate systems. Studies of capillary viscosity indicated that ionic medium is an effective strategy to modulate the polyelectrolyte effect and viscosity properties of alginates. On gelation, considerable differences were observed between alginate gels produced with Ca2+, Ba2+, Cu2+, Fe2+, Fe3+ and Zn2+ as crosslinkers, especially concerning shrinkage and morphological regularity. Stability assays with different polyphenols in the presence of alginate-gelling cations pointed to the choice of calcium, barium and zinc as safer crosslinkers. Alginate-based films loaded with epicatechin were prepared and the kinetics of release of the flavonoid investigated. The results with calcium, barium and zinc alginate matrices indicated that the release dynamics is dependent on film thicknesses, but also on the crosslinking metal used. On these grounds, an alginate-based system of convenient use was devised, so that flavonoids can be easily loaded at simple point-of-care conditions before dermal application. This epicatechin-loaded patch was tested on an ex-vivo skin model and demonstrated capacity to deliver therapeutically relevant concentrations on skin surface. Moreover, the flavonoid released was not modified and retained full antioxidant bioactivity. The alginate-based system proposed offers a multifunctional approach for flavonoid controllable delivery and protection of skin injured or under risk.
- Microneedling-enhanced dermal delivery of catechin and curcuminoid polyphenols from gel, patch and ointment formulationsPublication . Violante, Cristiana; Marques-da-Silva, Dorinda; Lagoa, RicardoPolyphenols exhibit a wide range of biological and pharmacological activities, yet their dermal delivery is often limited by skin permeability and formulation-dependent constraints. In this work, the potential of roller microneedling as a physical strategy to improve dermal delivery of representative polyphenols—epicatechin, epigallocatechin gallate (EGCG), and curcumin—was investigated using common topical dosage forms, namely polymeric gel, patch, and ointment. Standardized skin permeation parameters were first obtained using excised porcine skin under conditions of stratum corneum saturation. The microneedling procedure was characterized, and its effect on polyphenol transdermal permeation from each formulation type was evaluated using Franz diffusion cells. Maximum steady-state permeation fluxes varied from 13.2 μg/cm2/h (curcumin) to 708 μg/cm2/h (epicatechin). Roller microneedling produced well-defined microchannels across the stratum corneum, with a mean interchannel distance of 2.3 mm, without compromising skin integrity, and significantly enhanced polyphenol permeation from all tested vehicles. Depending on the compound and formulation, microneedling increased permeation fluxes and/or reduced lag times, with particularly relevant effects observed for gel-delivered curcumin and ointment-delivered EGCG. Moreover, the polyphenols exhibited a robust antioxidant activity (equivalent to micromolar ascorbic acid) after transdermal permeation, including following microneedle-assisted delivery, supporting the compatibility of microneedling and the formulation vehicles with polyphenol functionality. Overall enhancement factors were consistent, yielding approximately twofold increases in both permeation flux and antioxidant activity. These findings demonstrate that roller microneedling is a practical, low-invasive approach to enhance the dermal delivery of polyphenols from conventional topical formulations, offering a versatile strategy that complements formulation-based optimization for therapeutic and cosmetic applications.
- Molecular Dissection of Escherichia coli CpdB: Roles of the N Domain in Catalysis and Phosphate Inhibition, and of the C Domain in Substrate Specificity and Adenosine InhibitionPublication . López-Villamizar, Iralis; Cabezas, Alicia; Pinto, Rosa María; Canales, José; Ribeiro, João Meireles; Rodrigues, Joaquim Rui; Costas, María Jesús; Cameselle, José CarlosCpdB is a 3′-nucleotidase/2′ 3′-cyclic nucleotide phosphodiesterase, active also with rea-sonable efficiency on cyclic dinucleotides like c-di-AMP (3′,5′-cyclic diadenosine monophosphate) and c-di-GMP (3′,5′-cyclic diadenosine monophosphate). These are regulators of bacterial physi-ology, but are also pathogen-associated molecular patterns recognized by STING to induce IFN-β response in infected hosts. The cpdB gene of Gram-negative and its homologs of gram-positive bacteria are virulence factors. Their protein products are extracytoplasmic enzymes (either periplas-mic or cell–wall anchored) and can hydrolyze extracellular cyclic dinucleotides, thus reducing the innate immune responses of infected hosts. This makes CpdB(-like) enzymes potential targets for novel therapeutic strategies in infectious diseases, bringing about the necessity to gain insight into the molecular bases of their catalytic behavior. We have dissected the two-domain structure of Escherichia coli CpdB to study the role of its N-terminal and C-terminal domains (CpdB_Ndom and CpdB_Cdom). The specificity, kinetics and inhibitor sensitivity of point mutants of CpdB, and truncated proteins CpdB_Ndom and CpdB_Cdom were investigated. CpdB_Ndom contains the catalytic site, is inhibited by phosphate but not by adenosine, while CpdB_Cdom is inactive but contains a substrate-binding site that determines substrate specificity and adenosine inhibition of CpdB. Among CpdB substrates, 3′-AMP, cyclic dinucleotides and linear dinucleotides are strongly dependent on the CpdB_Cdom binding site for activity, as the isolated CpdB_Ndom showed much-diminished activity on them. In contrast, 2′,3′-cyclic mononucleotides and bis-4-nitrophenylphosphate were actively hydrolyzed by CpdB_Ndom, indicating that they are rather independent of the CpdB_Cdom binding site.