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1.
Int J Mol Sci ; 25(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38673736

RESUMEN

Abundant in citrus fruits, naringin (NAR) is a flavonoid that has a wide spectrum of beneficial health effects, including its anti-inflammatory activity. However, its use in the clinic is limited due to extensive phase I and II first-pass metabolism, which limits its bioavailability. Thus, lipid nanoparticles (LNPs) were used to protect and concentrate NAR in inflamed issues, to enhance its anti-inflammatory effects. To target LNPs to the CD44 receptor, overexpressed in activated macrophages, functionalization with hyaluronic acid (HA) was performed. The formulation with NAR and HA on the surface (NAR@NPsHA) has a size below 200 nm, a polydispersity around 0.245, a loading capacity of nearly 10%, and a zeta potential of about 10 mV. In vitro studies show the controlled release of NAR along the gastrointestinal tract, high cytocompatibility (L929 and THP-1 cell lines), and low hemolytic activity. It was also shown that the developed LNPs can regulate inflammatory mediators. In fact, NAR@NPsHA were able to decrease TNF-α and CCL-3 markers expression by 80 and 90% and manage to inhibit the effects of LPS by around 66% for IL-1ß and around 45% for IL-6. Overall, the developed LNPs may represent an efficient drug delivery system with an enhanced anti-inflammatory effect.


Asunto(s)
Antiinflamatorios , Flavanonas , Liposomas , Nanopartículas , Flavanonas/farmacología , Flavanonas/química , Humanos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Nanopartículas/química , Animales , Células THP-1 , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Ratones , Línea Celular , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Receptores de Hialuranos/metabolismo , Composición de Medicamentos
2.
Mar Drugs ; 21(5)2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37233496

RESUMEN

Fucoidan has been reported to present diverse bioactivities, but each extract has specific features from which a particular biological activity, such as immunomodulation, must be confirmed. In this study a commercially available pharmaceutical-grade fucoidan extracted from Fucus vesiculosus, FE, was characterized and its anti-inflammatory potential was investigated. Fucose was the main monosaccharide (90 mol%) present in the studied FE, followed by uronic acids, galactose, and xylose that were present at similar values (3.8-2.4 mol%). FE showed a molecular weight of 70 kDa and a sulfate content of around 10%. The expression of cytokines by mouse bone-marrow-derived macrophages (BMDMs) revealed that the addition of FE upregulated the expression of CD206 and IL-10 by about 28 and 22 fold, respectively, in respect to control. This was corroborated in a stimulated pro-inflammatory situation, with the higher expression (60 fold) of iNOS being almost completely reversed by the addition of FE. FE was also capable of reverse LPS-caused inflammation in an in vivo mouse model, including by reducing macrophage activation by LPS from 41% of positive CD11C to 9% upon fucoidan injection. Taken together, the potential of FE as an anti-inflammatory agent was validated, both in vitro and in vivo.


Asunto(s)
Fucus , Ratones , Animales , Lipopolisacáridos , Polisacáridos/farmacología , Citocinas
3.
Mar Drugs ; 21(3)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36976232

RESUMEN

Brown macroalgae are an important source of polysaccharides, mainly fucose-containing sulphated polysaccharides (FCSPs), associated with several biological activities. However, the structural diversity and structure-function relationships for their bioactivities are still undisclosed. Thus, the aim of this work was to characterize the chemical structure of water-soluble Saccharina latissima polysaccharides and evaluate their immunostimulatory and hypocholesterolemic activities, helping to pinpoint a structure-activity relationship. Alginate, laminarans (F1, neutral glucose-rich polysaccharides), and two fractions (F2 and F3) of FCSPs (negatively charged) were studied. Whereas F2 is rich in uronic acids (45 mol%) and fucose (29 mol%), F3 is rich in fucose (59 mol%) and galactose (21 mol%). These two fractions of FCSPs showed immunostimulatory activity on B lymphocytes, which could be associated with the presence of sulphate groups. Only F2 exhibited a significant effect in reductions in in vitro cholesterol's bioaccessibility attributed to the sequestration of bile salts. Therefore, S. latissima FCSPs were shown to have potential as immunostimulatory and hypocholesterolemic functional ingredients, where their content in uronic acids and sulphation seem to be relevant for the bioactive and healthy properties.


Asunto(s)
Laminaria , Phaeophyceae , Fucosa/química , Agua , Phaeophyceae/química , Polisacáridos/farmacología , Polisacáridos/química , Sulfatos , Ácidos Urónicos
4.
Int J Mol Sci ; 24(21)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37958633

RESUMEN

Tuberculosis is an infectious disease caused by the bacterial complex Mycobacterium tuberculosis. Despite the decline in the incidence and mortality of this disease over the years, the emergence of new strains of tuberculosis resistant to existing tuberculostatic drugs is currently one of the largest public health problems. The engineering and development of new drugs is a complex process; therefore, the modification and enhancement of the drugs already marked is a better and faster solution. Ethambutol (ETB) is an antimycobacterial drug used to treat tuberculosis; however, it is highly hygroscopic and is sparingly soluble in water. Therapeutic Deep Eutectic Solvents (THEDESs) are known to improve drug solubility, permeability, and hygroscopicity, among others. In this study, three THEDESs of ETB were synthesized with sucralose, glucose and glycerol and then encapsulated in nanostructured lipid carriers to improve their stability. This work is a proof of concept on the possibility of encapsulating the THEDESs, and results show that the encapsulation of ETB is possible, yielding formulations with a loading capacity superior to 8.5% and able to incorporate THEDESs and not just ETB.


Asunto(s)
Etambutol , Tuberculosis , Humanos , Solventes , Liposomas , Excipientes
5.
Molecules ; 28(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36615600

RESUMEN

Chlorella vulgaris is a green microalga with a high chlorophyll content, representing a valuable source of green pigments for food applications. As the application of whole biomass can promote an unpleasant fish-like flavor, the use of chlorophyll extract can overcome this drawback. However, chlorophylls tend to easily degrade when out of the chloroplasts, decreasing their potential as a food ingredient. Thus, to study the suitable conditions for isolated chlorophylls preservation, in this work, the influence of temperature (4 to 60 °C), light (dark or 24 h photoperiod), alkaline conditions (with or without aqueous NaOH addition), and modified atmosphere (air or argon atmosphere) on the stability of the color in ethanolic solutions obtained from C. vulgaris were studied. The loss of green color with temperature followed the first-order kinetics, with an activation energy of 74 kJ/mol. Below 28 °C and dark conditions were suitable to preserve isolated chlorophylls. The addition of NaOH and an inert argon-rich atmosphere did not exhibit a statistically positive effect on color preservation. In the case study, cooked cold rice was colored to be used in sushi. The color remained stable for up to 3 days at 4 °C. Therefore, this work showed that C. vulgaris chlorophylls could be preserved in ethanolic solutions at room or lower temperatures when protected from light, allowing them to obtain a suitable natural food ingredient to color foodstuffs.


Asunto(s)
Chlorella vulgaris , Ingredientes Alimentarios , Chlorella vulgaris/metabolismo , Argón , Hidróxido de Sodio , Clorofila/metabolismo
6.
Molecules ; 28(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37375143

RESUMEN

In this study, the chemical composition and antioxidant profile of five edible macroalgae, Fucus vesiculosus, Palmaria palmata, Porphyra dioica, Ulva rigida, and Gracilaria gracilis, cultivated in fully controlled closed systems, were determined. Protein, carbohydrates, and fat contents ranged between 12.4% and 41.8%, 27.6% and 42.0%, and 0.1% and 3.4%, respectively. The tested seaweeds presented considerable amounts of Ca, Mg, K, Mn, and Fe, which reinforce their favorable nutritional profile. Regarding their polysaccharide composition, Gracilaria gracilis and Porphyra dioica were rich in sugars common to agar-producing red algae, and Fucus vesiculosus was composed mainly of uronic acids, mannose, and fucose, characteristic of alginate and fucoidans, whereas rhamnose and uronic acid, characteristic of ulvans, predominated in Ulva rigida. Comparatively, the brown F. vesiculosus clearly stood out, presenting a high polysaccharide content rich in fucoidans, and higher total phenolic content and antioxidant scavenging activity, determined by DPPH and ABTS. The remarkable potential of these marine macroalgae makes them excellent ingredients for a wide range of health, food, and industrial applications.


Asunto(s)
Gracilaria , Rhodophyta , Algas Marinas , Ulva , Antioxidantes/farmacología , Antioxidantes/metabolismo , Algas Marinas/química , Rhodophyta/química , Gracilaria/química , Ulva/química , Polisacáridos/metabolismo
7.
Int J Mol Sci ; 23(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35887369

RESUMEN

Carbonaceous materials derived from biomass have been used as sustainable platforms for the growth of ZnO particles aiming the production of functional composite fillers. Kidney-bean pods were pyrolyzed by applying an experimental design that demonstrates that the specific surface area (SBET) of biochar is improved with increasing pyrolysis temperature combined with a short air-oxidation time. Meanwhile, the graphitization degree and the electrical conductivity (EC) of biochars were negatively affected by increasing the air-oxidation time. The biochar sample with the higher EC and the one with the higher SBET were selected to be functionalized with ZnO particles by a solvothermal methodology, obtaining composites with an EC and SBET properties superior to the ZnO-rGO composite, in addition to a similar antibacterial activity. The developed ZnO-biochar composite structures, which are more ecological and biocompatible than the ZnO composites derived from graphene sheets, can be applied as electrically conductive and active fillers.


Asunto(s)
Antiinfecciosos , Eliminación de Residuos , Óxido de Zinc , Antibacterianos/química , Antibacterianos/farmacología , Carbón Orgánico/química , Conductividad Eléctrica , Alimentos , Óxido de Zinc/química
8.
Int J Mol Sci ; 23(3)2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35163770

RESUMEN

Carbon nanostructures are widely used as fillers to tailor the mechanical, thermal, barrier, and electrical properties of polymeric matrices employed for a wide range of applications. Reduced graphene oxide (rGO), a carbon nanostructure from the graphene derivatives family, has been incorporated in composite materials due to its remarkable electrical conductivity, mechanical strength capacity, and low cost. Graphene oxide (GO) is typically synthesized by the improved Hummers' method and then chemically reduced to obtain rGO. However, the chemical reduction commonly uses toxic reducing agents, such as hydrazine, being environmentally unfriendly and limiting the final application of composites. Therefore, green chemical reducing agents and synthesis methods of carbon nanostructures should be employed. This paper reviews the state of the art regarding the green chemical reduction of graphene oxide reported in the last 3 years. Moreover, alternative graphitic nanostructures, such as carbons derived from biomass and carbon nanostructures supported on clays, are pointed as eco-friendly and sustainable carbonaceous additives to engineering polymer properties in composites. Finally, the application of these carbon nanostructures in polymer composites is briefly overviewed.


Asunto(s)
Grafito/síntesis química , Tecnología Química Verde/métodos , Biomasa , Arcilla/química , Grafito/química , Nanoestructuras
9.
Int J Mol Sci ; 22(18)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34576102

RESUMEN

Bionanocomposite materials have been designed as a promising route to enhance biopolymer properties, especially for food packaging application. The present study reports the preparation of bionanocomposite films of alginate with different loadings of pure reduced graphene oxide (rGO) or of mixed zinc oxide-rGO (ZnO-rGO) fillers by solvent casting. Sepiolite is used to make compatible rGO with the hydrophilic matrix. The addition of fillers to alginate matrix maintains the low water solubility promoted by the calcium chloride treatment, and, additionally, they demonstrate a weaker mechanical properties, and a slight increase in water vapor permeability and wettability. Due to the properties of ZnO-rGO, the alginate bionanocomposites show an increase of electrical conductivity with the increase of filler content. While the highest electrical conductivity (0.1 S/m) is achieved by the in-plane measurement, it is in the through-plane measurement the remarkable enhancement of almost 30 times greater than the alginate film. With 50% of ZnO-rGO filler, the bionanocomposites present the highest antioxidant and antibacterial activities. The combination of electrical conductivity with bioactive properties makes these films promising not only to extend food shelf-life but also to allow packaged food sterilization at low temperature.


Asunto(s)
Alginatos/química , Conductividad Eléctrica , Embalaje de Alimentos , Nanocompuestos/química , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Módulo de Elasticidad , Escherichia coli/efectos de los fármacos , Grafito/química , Pruebas de Sensibilidad Microbiana , Nanocompuestos/ultraestructura , Permeabilidad , Solubilidad , Espectrometría Raman , Staphylococcus aureus/efectos de los fármacos , Vapor , Resistencia a la Tracción , Agua/química , Humectabilidad , Difracción de Rayos X , Óxido de Zinc/química
10.
Molecules ; 26(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34361718

RESUMEN

Several classes of polysaccharides have been described to have hypocholesterolemic potential, namely cholesterol bioaccessibility and bioavailability. This review will highlight the main mechanisms by which polysaccharides are known to affect cholesterol homeostasis at the intestine, namely the effect (i) of polysaccharide viscosity and its influence on cholesterol bioaccessibility; (ii) on bile salt sequestration and its dependence on the structural diversity of polysaccharides; (iii) of bio-transformations of polysaccharides and bile salts by the gut microbiota. Different quantitative structure-hypocholesterolemic activity relationships have been explored depending on the mechanism involved, and these were based on polysaccharide physicochemical properties, such as sugar composition and ramification degree, linkage type, size/molecular weight, and charge. The information gathered will support the rationalization of polysaccharides' effect on cholesterol homeostasis and highlight predictive rules towards the development of customized hypocholesterolemic functional food.


Asunto(s)
Anticolesterolemiantes/química , Ácidos y Sales Biliares/química , Colesterol/química , Alimentos Funcionales/análisis , Mucosa Intestinal/metabolismo , Polisacáridos/química , Anticolesterolemiantes/metabolismo , Anticolesterolemiantes/uso terapéutico , Ácidos y Sales Biliares/metabolismo , Disponibilidad Biológica , Biotransformación , Colesterol/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Homeostasis/efectos de los fármacos , Homeostasis/fisiología , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología , Hígado/efectos de los fármacos , Hígado/metabolismo , Estructura Molecular , Peso Molecular , Polisacáridos/metabolismo , Polisacáridos/uso terapéutico , Electricidad Estática
11.
Mol Pharmacol ; 97(4): 295-303, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32102968

RESUMEN

The main objective of this study was to clarify the topical mechanisms underlying diclofenac-induced gastric toxicity by considering for the first time both ionization states of this nonsteroidal anti-inflammatory drug. 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes were the model system chosen to mimic the protective phospholipid layers of the gastric mucosa and to describe the interactions with diclofenac, considering the pH gradient found in the gastric mucosa (3 < pH < 7.4). Complementary experimental techniques were combined to evaluate the drug's affinity for DMPC bilayers, as well as to assess the drug's effects on the structural properties of the phospholipid bilayer. The diclofenac-DMPC interactions were clearly dependent on the drug's ionization state. Neutral diclofenac displayed greater affinity for DMPC bilayers than anionic diclofenac. Moreover, the protonated/neutral form of the drug induced more pronounced and/or distinct alterations in the structure of the DMPC bilayer than the deprotonated/ionized form, considering similar membrane concentrations. Therefore, neutral diclofenac-induced changes in the structural properties of the external phospholipid layers of the gastric mucosa may constitute an additional toxicity mechanism of this worldwide-used drug, which shall be considered for the development of safer therapeutic strategies. SIGNIFICANCE STATEMENT: Neutral or anionic diclofenac exerted distinct alterations in phosphatidylcholine bilayers, which are used in this work as models for the protective phospholipid layers of the gastric mucosa. Remarkable changes were induced by neutral diclofenac in the structural properties of the phospholipid bilayer, suggesting that both ionized and neutral states of nonsteroidal anti-inflammatory drugs must be considered to clarify their mechanisms of toxicity and to ultimately develop safer anti-inflammatory drugs.


Asunto(s)
Antiinflamatorios no Esteroideos/toxicidad , Diclofenaco/toxicidad , Dimiristoilfosfatidilcolina/química , Mucosa Gástrica/efectos de los fármacos , Membrana Dobles de Lípidos/química , Mucosa Gástrica/química , Concentración de Iones de Hidrógeno , Liposomas/química , Estructura Molecular , Dispersión del Ángulo Pequeño , Difracción de Rayos X
12.
Plant Cell Physiol ; 61(4): 814-825, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32016408

RESUMEN

Cell wall modification is integral to many plant developmental processes where cells need to separate, such as abscission. However, changes in cell wall composition during natural fruit abscission are poorly understood. In olive (Olea europaea L.), some cultivars such as 'Picual' undergo massive natural fruit abscission after fruit ripening. This study investigates the differences in cell wall polysaccharide composition and the localization of pectins and arabinogalactan protein (AGP) in the abscission zone (AZ) during cell separation to understand fruit abscission control in 'Picual' olive. To this end, immunogold labeling employing a suite of monoclonal antibodies to cell wall components (JIM13, LM5, LM6, LM19 and LM20) was investigated in olive fruit AZ. Cell wall polysaccharide extraction revealed that the AZ cell separation is related to the de-esterification and degradation of pectic polysaccharides. Moreover, ultrastructural localization showed that both esterified and unesterified homogalacturonans (HGs) localize mainly in the AZ cell walls, including the middle lamella and tricellular junction zones. Our results indicate that unesterified HGs are likely to contribute to cell separation in the olive fruit AZ. Similarly, immunogold labeling demonstrated a decrease in both galactose-rich and arabinose-rich pectins in AZ cell walls during ripe fruit abscission. In addition, AGPs were localized in the cell wall, plasma membrane and cytoplasm of AZ cells with lower levels of AGPs during ripe fruit abscission. This detailed temporal profile of the cell wall polysaccharide composition, and the pectins and AGP immunolocalization in the olive fruit AZ, offers new insights into cell wall remodeling during ripe fruit abscission.


Asunto(s)
Pared Celular/ultraestructura , Frutas/química , Galactanos/ultraestructura , Mucoproteínas/ultraestructura , Olea/química , Pectinas/ultraestructura , Arabinosa/metabolismo , Esterificación , Galactosa/metabolismo , Proteínas de Plantas/ultraestructura , Polisacáridos/ultraestructura
13.
Pediatr Transplant ; 23(6): e13463, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31332958

RESUMEN

The Brazilian collaborative registry for pediatric renal transplantation began in 2004 as a multicenter initiative aimed at analyzing, reporting, and disseminating the results of pediatric renal transplantation in Brazil. Data from all pediatric renal transplants performed from January 2004 to May 2018 at the 13 participating centers were analyzed. A total of 2744 pediatric renal transplants were performed in the thirteen participating centers. The median age at transplantation was 12.2 years, with the majority being male recipients (56%). The main underlying diseases were CAKUT (40.5%) and glomerulopathy (28%). 1981 (72%) of the grafts were from deceased donors (DD). Graft survival at one year (censored by death) was 94% in the live donor group (LD) and 91% in the DD group (log-rank test P < 0.01). The patient's survival at one and 5 years was 97% and 95% for the LD group and 96% and 93% for the DD group (log-rank test P = 0.02). The graft loss rate was 19% (n = 517), more frequently caused by vascular thrombosis (n = 102) and chronic graft nephropathy (n = 90). DD recipients had 1.6 (1.0-2.2) times greater chance of death and 1.5 (1.2-1.8) times greater chance of graft loss compared to LD recipients. The mortality rate was 5.4% (n = 148), mainly due to infection (n = 69) and cardiovascular disease (n = 28). The results of this collaborative pediatric renal transplant record are comparable to other international registries, although we still have a high infection rate as a cause of death.


Asunto(s)
Supervivencia de Injerto , Enfermedades Renales/cirugía , Trasplante de Riñón , Sistema de Registros , Adolescente , Brasil , Niño , Ciclosporina/farmacología , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Humanos , Cooperación Internacional , Enfermedades Renales/complicaciones , Fallo Renal Crónico , Donadores Vivos , Masculino , Complicaciones Posoperatorias/mortalidad , Trombosis/fisiopatología , Obtención de Tejidos y Órganos
14.
Ecotoxicol Environ Saf ; 173: 293-304, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30776562

RESUMEN

S-metolachlor (SMOC) and terbuthylazine (TBA) are herbicides that commonly appear as active ingredients (a.i.) in the composition of plant protection products. In a previous work, experimental bioassays were performed using those chemicals to find suitable molecular biomarkers to assess its toxicity to the non-target species Scrobicularia plana. The results obtained showed that the pollutants produce mortality and biochemical changes at the species, namely in protein contents and enzymatic activity levels. Thus, for a better understanding of the total biochemical impacts of those pollutants in S. plana, the composition of fatty acids (FA) and carbohydrates (CH) of the survival organisms are investigated here. In addition, since this species is edible its biochemical profile is directly related to its nutritious quality, which is analysed in this study. Furthermore, the analyses were performed in two types of tissue - the muscle and visceral mass of each survival organism. The greatest changes in FA composition are observable in small size class, being the most sensitive size class both at the toxicological and biochemical level. FA contents are higher in small organisms, both at the field and under laboratory conditions, being the disparity between size classes higher in visceral masses than in muscles. Indeed, muscles adequately represent the FA profile since those molecules appear in higher content in this tissue compared to visceral masses, becoming the better indicator tissue of biochemical changes. Besides, using muscles, less amount of biomass is needed, so it turns out to be the most cost-effective tissue to be used as endpoint in future studies. FA profiles observed at SMOC and TBA exposure are different, organisms from TBA exposure presenting a lower nutritious quality, in terms of FA abundance and diversity, than the organisms exposed to SMOC. Still, SMOC produces reductions of HUFA, essential fatty acids that cannot be synthesized by the species. Moreover, HUFA (mostly EPA and DHA) occupied the greatest part of the FA composition of organisms exposed to the control treatments and to TBA; however, the decreases of HUFA caused by the SMOC exposure change the profiles and make SFA the most dominant group. These findings represent a risk of low occurrence of essential fatty acids in entire aquatic environments exposed to the chemicals studied. Regarding CH, glucose is the only monosaccharide found in S. plana which was expected since glycogen is the main polysaccharide in animal tissues. In general, the glucose content increases with a concentration of pollutants, whereas the glycogen concentration decreases, suggesting that the glucose is being released as a response to chemical stress. Thus, this work presents tools to assess biochemical impacts of S-metolachlor and terbuthylazine in aquatic systems and to goes deeper in the knowledge of these pollutants' toxicity to non-target species to predict its propagation through aquatic trophic webs.


Asunto(s)
Acetamidas/efectos adversos , Bivalvos/efectos de los fármacos , Metabolismo de los Hidratos de Carbono , Ácidos Grasos/metabolismo , Herbicidas/efectos adversos , Triazinas/efectos adversos , Contaminantes Químicos del Agua/efectos adversos , Animales , Estuarios , Portugal
15.
Molecules ; 24(3)2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30709010

RESUMEN

(1) Background: Membrane lipids have been disregarded in drug development throughout the years. Recently, they gained attention in drug design as targets, but they are still disregarded in the latter stages. Thus, this study aims to highlight the relevance of considering membrane lipids in the preclinical phase of drug development. (2) Methods: The interactions of a drug candidate for clinical use (licofelone) with a membrane model system made of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were evaluated by combining Langmuir isotherms, Brewster angle microscopy (BAM), polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS), and grazing-incidence X-ray diffraction (GIXD) measurements. (3) Results: Licofelone caused the expansion of the DPPC isotherm without changing the lipid phase transition profile. Moreover, licofelone induced the reduction of DPPC packing density, while increasing the local order of the DPPC acyl chains. (4) Conclusions: The licofelone-induced alterations in the structural organization of phosphatidylcholine monolayers may be related to its pharmacological actions. Thus, the combination of studying drug-membrane interactions with the pharmacological characterization that occurs in the preclinical stage may gather additional information about the mechanisms of action and toxicity of drug candidates. Ultimately, the addition of this innovative step shall improve the success rate of drug development.


Asunto(s)
1,2-Dipalmitoilfosfatidilcolina/química , Pirroles/química , Desarrollo de Medicamentos , Lípidos de la Membrana/química , Microscopía , Estructura Molecular , Análisis Espectral , Temperatura
16.
Molecules ; 24(17)2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31484299

RESUMEN

Commercial production of microalgal biomass for food and feed is a recent worldwide trend. Although it is common to publish nutritional data for microalgae grown at the lab-scale, data about industrial strains cultivated in an industrial setting are scarce in the literature. Thus, here we present the nutritional composition and a microbiological and toxicological evaluation of Tetraselmis sp. CTP4 biomass, cultivated in 100-m3 photobioreactors at an industrial production facility (AlgaFarm). This microalga contained high amounts of protein (31.2 g/100 g), dietary fibres (24.6 g/100 g), digestible carbohydrates (18.1 g/100 g) and ashes (15.2 g/100 g), but low lipid content (7.04 g/100 g). The biomass displayed a balanced amount of essential amino acids, n-3 polyunsaturated fatty acids, and starch-like polysaccharides. Significant levels of chlorophyll (3.5 g/100 g), carotenoids (0.61 g/100 g), and vitamins (e.g., 79.2 mg ascorbic acid /100 g) were also found in the biomass. Conversely, pathogenic bacteria, heavy metals, cyanotoxins, mycotoxins, polycyclic aromatic hydrocarbons, and pesticides were absent. The biomass showed moderate antioxidant activity in several in vitro assays. Taken together, as the biomass produced has a balanced biochemical composition of macronutrients and (pro-)vitamins, lacking any toxic contaminants, these results suggest that this strain can be used for nutritional applications.


Asunto(s)
Vitaminas/metabolismo , Antioxidantes/metabolismo , Biomasa , Reactores Biológicos/microbiología , Microalgas/fisiología
17.
Molecules ; 24(3)2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30678085

RESUMEN

Following our previous work on the antitumor activity of acetylated flavonosides, a new acetylated xanthonoside, 3,6-bis(2,3,4,6-tetra-O-acetyl-ß-glucopyranosyl)xanthone (2), was synthesized and discovered as a potent inhibitor of tumor cell growth. The synthesis involved the glycosylation of 3,6-di-hydroxyxanthone (1) with acetobromo-α-d-glucose. Glycosylation with silver carbonate decreased the amount of glucose donor needed, comparative to the biphasic glycosylation. Xanthone 2 showed a potent anti-growth activity, with GI50 < 1 µM, in human cell lines of breast, lung, and glioblastoma cancers. Current treatment for invasive brain glioma is still inadequate and new agents against glioblastoma with high brain permeability are urgently needed. To overcome these issues, xanthone 2 was encapsulated in a liposome. To increase the well-known low stability of these drug carriers, a proliposome formulation was developed using the spray drying method. Both formulations were characterized and compared regarding three months stability and in vitro anti-growth activity. While the proliposome formulation showed significantly higher stability, it was at the expense of losing its biocompatibility as a drug carrier in higher concentrations. More importantly, the new xanthone 2 was still able to inhibit the growth of glioblastoma cells after liposome formulation.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Glioma/tratamiento farmacológico , Liposomas/farmacología , Xantonas/farmacología , Carbonatos/química , Línea Celular Tumoral , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Glioma/patología , Glucosa/química , Glicosilación/efectos de los fármacos , Humanos , Liposomas/síntesis química , Liposomas/química , Compuestos de Plata/química , Xantonas/síntesis química , Xantonas/química
18.
Chem Rec ; 18(7-8): 1138-1149, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29517853

RESUMEN

Chitosan-based functional materials are emerging for food applications. The covalent bonding of molecular entities demonstrates to enhance resistance to the typical acidity of food assigning mechanical and moisture/gas barrier properties. Moreover, the grafting to chitosan of some functional molecules, like phenolic compounds or essential oils, gives antioxidant, antimicrobial, among others properties to chitosan. The addition of nanofillers to chitosan and other biopolymers improves the already mentioned required properties for food applications and can attribute electrical conductivity and magnetic properties for active and intelligent packaging. Electrical conductivity is a required property for the processing of food at low temperature using electric fields or for sensors application.


Asunto(s)
Quitosano/química , Embalaje de Alimentos , Nanocompuestos/química , Antiinfecciosos/química , Antioxidantes/química , Conductividad Eléctrica , Fenómenos Magnéticos
19.
Phys Chem Chem Phys ; 20(21): 14398-14409, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29770409

RESUMEN

Gastrointestinal (GI) toxicity is a major drawback of the chronic use of nonsteroidal anti-inflammatory drugs (NSAIDs). The NSAIDs topical actions on the protective phospholipid layers of the GI mucosa seem to be a central toxicity mechanism of these pharmaceuticals. This work describes the interactions of acemetacin, a commercialized NSAID, with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers at pH 3.0, 5.0, and 7.4. This pH range was chosen to mimic the pH gradient found in the gastric mucosa, and to ultimately gain insights into the mechanisms underlying the acemetacin-induced gastric toxicity. Various experimental techniques were combined to characterize the partitioning of acemetacin in DMPC bilayers, and its effects on the phase transition behavior, as well as the structure and dynamics of DMPC bilayers. The acemetacin-DMPC interactions were clearly pH-dependent. The neutral (protonated) form of acemetacin had more affinity for the DMPC bilayer than the negatively charged form. Due to the higher affinity of neutral acemetacin, the drug effects on the phase transition and the structure and dynamics of the DMPC bilayer were more pronounced at lower pH values. In general, acemetacin decreased the temperature and the cooperativity of the lipid phase transition and induced changes in the packing and dynamics of the DMPC bilayer. These results support the hypothesis that acemetacin-induced gastric toxicity may be related to its effects on the protective phospholipid layers of the mucosal barrier.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Indometacina/análogos & derivados , Fosfatidilcolinas/química , Concentración de Iones de Hidrógeno , Indometacina/química , Cinética , Membrana Dobles de Lípidos/química , Estructura Molecular , Transición de Fase , Electricidad Estática , Temperatura
20.
Med Res Rev ; 37(4): 802-859, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28005273

RESUMEN

The efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) against inflammation, pain, and fever has been supporting their worldwide use in the treatment of painful conditions and chronic inflammatory diseases until today. However, the long-term therapy with NSAIDs was soon associated with high incidences of adverse events in the gastrointestinal tract. Therefore, the search for novel drugs with improved safety has begun with COX-2 selective inhibitors (coxibs) being straightaway developed and commercialized. Nevertheless, the excitement has fast turned to disappointment when diverse coxibs were withdrawn from the market due to cardiovascular toxicity. Such events have once again triggered the emergence of different strategies to overcome NSAIDs toxicity. Here, an integrative review is provided to address the breakthroughs of two main approaches: (i) the association of NSAIDs with protective mediators and (ii) the design of novel compounds to target downstream and/or multiple enzymes of the arachidonic acid cascade. To date, just one phosphatidylcholine-associated NSAID has already been approved for commercialization. Nevertheless, the preclinical and clinical data obtained so far indicate that both strategies may improve the safety of nonsteroidal anti-inflammatory therapy.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Animales , Humanos , Relación Estructura-Actividad
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