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1.
ACS Appl Bio Mater ; 7(5): 3283-3294, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38727030

RESUMEN

Medical implants are constantly facing the risk of bacterial infections, especially infections caused by multidrug resistant bacteria. To mitigate this problem, gold nanoparticles with alkyl bromide moieties (Au NPs-Br) on the surfaces were prepared. Xenon light irradiation triggered the plasmon effect of Au NPs-Br to induce free radical graft polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA), leading to the formation of poly(DMAEMA) brush-grafted Au NPs (Au NPs-g-PDM). The Au NPs-g-PDM nanocomposites were conjugated with phytic acid (PA) via electrostatic interaction and van der Waals interaction. The as-formed aggregates were deposited on the titanium (Ti) substrates to form the PA/Au NPs-g-PDM (PAP) hybrid coatings through surface adherence of PA and the gravitational effect. Synergistic bactericidal effects of contact-killing caused by the cationic PDM brushes, and local heating generated by the Au NPs under near-infrared irradiation, conferred strong antibacterial effects on the PAP-deposited Ti (Ti-PAP) substrates. The synergistic bactericidal effects reduced the threshold temperature required for the photothermal sterilization, which in turn minimized the secondary damage to the implant site. The Ti-PAP substrates exhibited 97.34% and 99.97% antibacterial and antiadhesive efficacy, respectively, against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the control under in vitro antimicrobial assays. Furthermore, the as-constructed Ti-PAP surface exhibited a 99.42% reduction in the inoculated S. aureus under in vivo assays. In addition, the PAP coatings exhibited good biocompatibility in the hemolysis and cytotoxicity assays as well as in the subcutaneous implantation of rats.


Asunto(s)
Antibacterianos , Escherichia coli , Oro , Ensayo de Materiales , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Ácido Fítico , Staphylococcus aureus , Oro/química , Oro/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Nanopartículas del Metal/química , Ácido Fítico/química , Ácido Fítico/farmacología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Animales , Propiedades de Superficie , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Cationes/química , Cationes/farmacología , Polímeros/química , Polímeros/farmacología , Titanio/química , Titanio/farmacología
2.
Food Res Int ; 186: 114321, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729691

RESUMEN

Biogenic nanoparticles are promising carriers to deliver essential minerals. Here, calcium-enriched polyphosphate nanoparticles (CaPNPs) with a Ca/P molar ratio > 0.5 were produced by Synechococcus sp. PCC 7002 in the growth medium containing 1.08 g/L CaCl2, and had nearly spherical morphologies with a wide size distribution of 5-75 nm and strongly anionic surface properties with an average ζ-potential of -39 mV, according to dynamic light-scattering analysis, transmission and scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The ex-vivo ligated mouse ileal loop assays found that calcium in CaPNPs was readily available to intestinal absorption via both ion channel-mediated and endocytic pathways, specifically invoking macropinocytic internalization, lysosomal degradation, and transcytosis. Rat oral pharmacokinetics revealed that CaPNPs had a calcium bioavailability approximately 100 % relative to that of CaCl2 and more than 1.6 times of that of CaCO3. CaPNPs corrected the retinoic acid-induced increase in serum calcium, phosphorus, and bone-specific alkaline phosphatase, and decrease in serum osteocalcin, bone mineral content/density, and femoral geometric parameters with an efficacy equivalent to CaCl2 and markedly greater than CaCO3. In contrast to CaCl2, CaPNPs possessed desirable resistance against phytate's antagonistic action on calcium absorption in these ex vivo and in vivo studies. Overall, CaPNPs are attractive as a candidate agent for calcium supplementation, especially to populations on high-phytate diets.


Asunto(s)
Disponibilidad Biológica , Calcio , Microalgas , Nanopartículas , Ácido Fítico , Polifosfatos , Animales , Polifosfatos/química , Ratones , Ácido Fítico/química , Calcio/metabolismo , Masculino , Ratas , Absorción Intestinal/efectos de los fármacos , Ratas Sprague-Dawley
3.
Int J Biol Macromol ; 270(Pt 1): 132260, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38734338

RESUMEN

The utilization of bioderived flame retardants in biodegradable poly (lactic acid) (PLA) has profound practical implications for extending the widespread application of PLA composites and protecting the environment. Nevertheless, there are still certain challenges that require prompt attention, especially the ineffectiveness of bio-based flame retardants and their deterioration of the mechanical properties of PLA. This work introduced triglycidyl isocyanurate (TGIC), which has multiple epoxy functions, into the self-assembly process of phytic acid (PA) and chitosan (CS). The epoxy-modified bioderived flame retardant PA@CS-TGIC (PCT) was well dispersed in the PLA matrix and had a strong interfacial adhesion, while also TGIC had a synergistic char-forming effect. By compounding epoxy-modified ammonium polyphosphate (MAPP), 3%PCT/MAPP-PLA composites may reach a LOI value of 28.8 % and UL-94 V-0 rating. Simultaneously, the melting droplets had been considerably reduced. Tensile strength of the 3%PCT/MAPP-PLA composites was 67.0 MPa, 10.8 % higher than that of pure PLA. This work paves a new avenue for the development of PLA composites with robust mechanical and flame retardant properties.


Asunto(s)
Retardadores de Llama , Poliésteres , Poliésteres/química , Resistencia a la Tracción , Quitosano/química , Ácido Fítico/química , Triazinas/química
4.
Biochemistry ; 63(9): 1097-1106, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38669178

RESUMEN

As a key component for NADPH oxidase 2 (NOX2) activation, the peripheral membrane protein p47phox translocates a cytosolic activating complex to the membrane through its PX domain. This study elucidates a potential regulatory mechanism of p47phox recruitment and NOX2 activation by inositol hexaphosphate (IP6). Through NMR, fluorescence polarization, and FRET experimental results, IP6 is shown to be capable of breaking the lipid binding and membrane anchoring events of p47phox-PX with low micromolar potency. Other phosphorylated inositol species such as IP5(1,3,4,5,6), IP4(1,3,4,5), and IP3(1,3,4) show weaker binding and no ability to inhibit lipid interactions in physiological concentration ranges. The low micromolar potency of IP6 inhibition of the p47phox membrane anchoring suggests that physiologically relevant concentrations of IP6 serve as regulators, as seen in other membrane anchoring domains. The PX domain of p47phox is known to be promiscuous to a variety of phosphatidylinositol phosphate (PIP) lipids, and this regulation may help target the domain only to the membranes most highly enriched with the highest affinity PIPs, such as the phagosomal membrane, while preventing aberrant binding to other membranes with high and heterogeneous PIP content, such as the plasma membrane. This study provides insight into a potential novel regulatory mechanism behind NOX2 activation and reveals a role for small-molecule regulation in this important NOX2 activator.


Asunto(s)
NADPH Oxidasas , Ácido Fítico , Ácido Fítico/metabolismo , Ácido Fítico/química , NADPH Oxidasas/metabolismo , NADPH Oxidasas/antagonistas & inhibidores , Humanos , Membrana Celular/metabolismo , NADPH Oxidasa 2/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo
5.
Sci Total Environ ; 837: 155525, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35489486

RESUMEN

Myo-inositol hexakisphosphate (myo-IHP) is one of the most common soil organic phosphorus (P) species in soil. Its retention in soil is often competed by phosphate, making bioavailability of P species difficult. In this study, the adsorption mechanism of myo-IHP at the amorphous aluminum (oxyhydr)oxide (AAH)-water interface was investigated at pH 6.5 in the presence of phosphate using batch adsorption experiments and solution 31P NMR spectroscopy. The ratio of [myo-IHP]i/[phosphate]i (Ri) was kept 0.33-3 while ligand addition was varied. In the absence of phosphate, myo-IHP forms inner-sphere surface complexes in AAH via P1,3, P2, P4,6, and P5 functional group coordination. When two ligands were simultaneously added, fewer P functional groups of myo-IHP coordinated to AAH and the surface complexes were altered with the coordination of mainly P1,3 and P2 functional groups. When phosphate was pre-adsorbed, myo-IHP adsorption decreased by 8.0-44% compared to the respective simultaneous addition system. P2 or P5 functional group was predominantly coordinated to the AAH surfaces at Ri = 0.33. Myo-IHP pre-adsorption resulted in an increase in the final myo-IHP adsorption compared to that in the simultaneous addition system under the respective Ri values (0.33-3). In this system, P1,3, P2, P4,6, and P5 functional groups were coordinated to form inner-sphere surface complexes regardless of Ri. The study revealed that the functional group specific adsorption mechanism of myo-IHP at the AAH-water interface was affected by addition sequence and Ri of two ligands. The competitive adsorption between organic P and phosphate plays an important role in the fate of P in soils.


Asunto(s)
Aluminio , Ácido Fítico , Adsorción , Ligandos , Fosfatos , Ácido Fítico/química , Suelo , Agua
6.
Carbohydr Polym ; 282: 119104, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35123757

RESUMEN

Rice and corn starches were subjected to dry heating with rice bran extract or sodium trimetaphosphate (STMP)/sodium tripolyphosphate (STPP) for starch phosphorylation. Phytate in rice bran extract or STMP/STPP increased the concentration of phosphorus in rice and maize starches. The highest concentrations of phosphorus were induced in rice starch with rice bran extract and in corn starch with STMP/STPP. 31P NMR analysis indicated that the rice bran extract and STMP/STPP produced monostarch monophosphate under the same reaction conditions. Rice and corn starches phosphorylated with rice bran extract or STMP/STPP demonstrated great peak viscosity and low pasting temperatures. Although starch phosphorylated with either rice bran extract or STMP/STPP showed higher paste clarity, solubility, and swelling power than native starch, these parameters were optimal in rice starch phosphorylated with rice bran extract. Therefore, dry heating with rice bran extract induced phytate-mediated phosphorylation with the typical physicochemical properties of starch phosphates.


Asunto(s)
Oryza , Ácido Fítico/química , Extractos Vegetales/química , Almidón/química , Calor , Fósforo/análisis , Fosforilación , Polifosfatos/química , Zea mays
7.
J Sci Food Agric ; 102(3): 931-939, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34265087

RESUMEN

BACKGROUND: Reducing anti-nutritional factors like phytates in seed protein products requires an ongoing effort. This study was the first to investigate the phytic acid content in seabuckthorn seed protein (SSP) and its reduction by an exogenous phytase during protein isolation from seabuckthorn seed meal through the common alkaline solubilization-isoelectric precipitation process. RESULTS: The additional phytase treatment could reduce the content of phytic acid from 22.46 to 13.27 g kg-1 , leading to SSP products with lighter color (lower ΔE* ), higher protein solubility, higher in vitro digestibility, but lower phenolic antioxidant content (including flavonoids and procyanidins) and some beneficial ions like Ca, Fe, Mg, and Zn. The Fourier transform infrared (FTIR) results indicated that the secondary structure of protein changed under the treatment with phytase. Correlation analysis showed that L* was significantly negatively correlated with TP, TPC and TF (P < 0.001), while a* and b* were significantly positively correlated with them (P < 0.001). CONCLUSIONS: There may be a trade-off between protein functionalities and other health-promoting components when a phytase treatment is included in SSP isolation. © 2021 Society of Chemical Industry.


Asunto(s)
6-Fitasa/química , Manipulación de Alimentos/métodos , Hippophae/química , Proteínas de Plantas/química , Álcalis/química , Biocatálisis , Precipitación Química , Color , Ácido Fítico/química , Semillas/química , Solubilidad
8.
Nat Commun ; 12(1): 5969, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34645811

RESUMEN

The Yersinia outer protein J (YopJ) family effectors are widely deployed through the type III secretion system by both plant and animal pathogens. As non-canonical acetyltransferases, the enzymatic activities of YopJ family effectors are allosterically activated by the eukaryote-specific ligand inositol hexaphosphate (InsP6). However, the underpinning molecular mechanism remains undefined. Here we present the crystal structure of apo-PopP2, a YopJ family member secreted by the plant pathogen Ralstonia solanacearum. Structural comparison of apo-PopP2 with the InsP6-bound PopP2 reveals a substantial conformational readjustment centered in the substrate-binding site. Combining biochemical and computational analyses, we further identify a mechanism by which the association of InsP6 with PopP2 induces an α-helix-to-ß-strand transition in the catalytic core, resulting in stabilization of the substrate recognition helix in the target protein binding site. Together, our study uncovers the molecular basis governing InsP6-mediated allosteric regulation of YopJ family acetyltransferases and further expands the paradigm of fold-switching proteins.


Asunto(s)
Acetiltransferasas/química , Apoproteínas/química , Arabidopsis/microbiología , Proteínas Bacterianas/química , Ácido Fítico/química , Ralstonia solanacearum/química , Acetiltransferasas/genética , Acetiltransferasas/metabolismo , Regulación Alostérica , Apoproteínas/genética , Apoproteínas/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dominio Catalítico , Clonación Molecular , Cristalografía por Rayos X , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Modelos Moleculares , Ácido Fítico/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Ralstonia solanacearum/enzimología , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Especificidad por Sustrato , Nicotiana/microbiología
9.
Biomed Mater ; 16(6)2021 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-34492639

RESUMEN

Due to its excellent biocompatibility and anti-inflammatory activity, amniotic membrane (AM) has attracted much attention from scholars. However, its clinical application in vascular reconstruction was limited for poor processability, rapid biodegradation, and insufficient hemocompatibility. A naturally extracted substance with good cytocompatibility, phytic acid (PA), which can quickly form strong and stable hydrogen bonds on the tissue surface, was used to crosslink decellularized AM (DAM) to prepare a novel vascular replacement material. The results showed that PA-fixed AM had excellent mechanical strength and resistance to enzymatic degradation as well as appropriate surface hydrophilicity. Among all samples, 2% PA-fixed specimen showed excellent human umbilical vein endothelial cells (HUVECs)-cytocompatibility and hemocompatibility. It could also stimulate the secretion of vascular endothelial growth factor and endothelin-1 from seeded HUVECs, indicating that PA might promote neovascularization after implantation of PA-fixed specimens. Also, 2% PA-fixed specimen could inhibit the secretion of tumor necrosis factor-αfrom co-cultured macrophages, thus might reduce the inflammatory response after sample implantation. Finally, the results ofex vivoblood test andin vivoexperiments confirmed our deduction that PA might promote neovascularization after implantation. All the results indicated that prepared PA-fixed DAM could be considered as a promising small-diameter vascular replacement material.


Asunto(s)
Amnios , Antiinflamatorios , Matriz Extracelular Descelularizada , Ácido Fítico , Amnios/química , Amnios/citología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Vasos Sanguíneos/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Matriz Extracelular Descelularizada/química , Matriz Extracelular Descelularizada/farmacología , Matriz Extracelular Descelularizada/toxicidad , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ensayo de Materiales , Ácido Fítico/química , Ácido Fítico/farmacología , Conejos , Ratas , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
Amino Acids ; 53(10): 1559-1568, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34536129

RESUMEN

S-adenosyl-L-methionine (SAM), the main endogenous methyl donor, is the adenosyl derivative of the amino acid methionine, which displays many important roles in cellular metabolism. It is widely used as a food supplement and in some countries is also marketed as a drug. Its interesting nutraceutical and pharmacological properties prompted us to evaluate the pharmacokinetics of a new form of SAM, the phytate salt. The product was administered orally to rats and pharmacokinetic parameters were evaluated by comparing the results with that obtained by administering the SAM tosylated form (SAM PTS). It was found that phytate anion protects SAM from degradation, probably because of steric hindrance exerted by the counterion, and that the SAM phytate displayed significant better pharmacokinetic parameters compared to SAM PTS. These results open to the perspective of the use of new salts of SAM endowed with better pharmacokinetic properties.


Asunto(s)
S-Adenosilmetionina/química , S-Adenosilmetionina/farmacocinética , Administración Oral , Animales , Área Bajo la Curva , Disponibilidad Biológica , Estabilidad de Medicamentos , Femenino , Masculino , Ácido Fítico/química , Ratas Sprague-Dawley , S-Adenosilmetionina/administración & dosificación , S-Adenosilmetionina/sangre
11.
Molecules ; 25(22)2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33198256

RESUMEN

Several studies have identified specific signalling functions for inositol polyphosphates (IPs) in different cell types and have led to the accumulation of new information regarding their cellular roles as well as new insights into their cellular production. These studies have revealed that interaction of IPs with several proteins is critical for stabilization of protein complexes and for modulation of enzymatic activity. This has not only revealed their importance in regulation of several cellular processes but it has also highlighted the possibility of new pharmacological interventions in multiple diseases, including cancer. In this review, we describe some of the intracellular roles of IPs and we discuss the pharmacological opportunities that modulation of IPs levels can provide.


Asunto(s)
Fosfatos de Inositol/metabolismo , Inositol/química , Ácido Fítico/metabolismo , Animales , Línea Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/química , Endocitosis , Exocitosis , Humanos , Fosfatos de Inositol/química , Ratones , Ácido Fítico/química , Agregación Plaquetaria , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Replicación Viral
12.
J Nutr ; 150(10): 2666-2672, 2020 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-32805002

RESUMEN

BACKGROUND: Iron deficiency is a major public health concern in Ethiopia, where the traditional diet is based on tef injera. Iron absorption from injera is low due to its high phytic acid (PA) content. OBJECTIVES: We investigated ways to increase iron absorption from FeSO4-fortified tef injera in normal-weight healthy women (aged 21-29 y). METHODS: Study A (n = 22) investigated the influence on fractional iron absorption (FIA) from FeSO4-fortified injera of 1) replacing 10% tef flour with whole wheat flour (a source of wheat phytase), or 2) adding an isolated phytase from Aspergillus niger. Study B (n = 18) investigated the influence on FIA of replacing FeSO4 in tef injera with different amounts of NaFeEDTA. In both studies, the iron fortificants were labeled with stable isotopes and FIA was calculated from erythrocyte incorporation of stable iron isotopes 14 d after administration. RESULTS: In study A, the median (IQR) FIA from the 100% tef injera meal was 1.5% (0.7-2.8%). This increased significantly (P < 0.05) to 5.3% (2.4-7.1%) on addition of 10% whole wheat flour, and to 3.6% (1.6-6.2%) on addition of A. niger phytase. PA content of the 3 meals was 0.62, 0.20, and 0.02 g/meal, respectively. In study B, the median (IQR) FIA from the 100% tef injera meal was 3.3% (1.1-4.4%) and did not change significantly (P > 0.05) on replacing 50% or 75% of FeSO4 with NaFeEDTA. CONCLUSIONS: FIA from tef injera by young women was very low. NaFeEDTA was ineffective at increasing iron absorption, presumably due to the relatively low EDTA:Fe molar ratios. Phytate degradation, however, greatly increased during tef fermentation on addition of native or isolated phytases. Replacing 10% tef with whole wheat flour during injera fermentation tripled FIA in young women and should be considered as a potential strategy to improve iron status in Ethiopia.


Asunto(s)
Eragrostis/genética , Harina/análisis , Hierro/farmacocinética , Ácido Fítico/química , Triticum , Adulto , Biofortificación , Transporte Biológico/efectos de los fármacos , Culinaria , Estudios Cruzados , Femenino , Fermentación , Compuestos Ferrosos/administración & dosificación , Alimentos Fortificados , Humanos , Hierro/sangre , Hierro/metabolismo , Isótopos de Hierro , Ácido Fítico/metabolismo , Granos Enteros , Adulto Joven
13.
Sci Rep ; 10(1): 11917, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32681007

RESUMEN

[223Ra]RaCl2 is the first alpha-particle emitting radiopharmaceutical to be used for castration-resistant prostate cancer patients with bone metastases because of its excellent therapeutic effects. [223Ra]RaCl2 is excreted via the intestine into feces, and some is absorbed from the intestine into the blood, which may be undesirable in terms of the exposure to radiation. Recently, we showed that a complex of myo-inositol-hexakisphosphate (InsP6) with zinc is a useful decorporation agent against radiostrontium. In this study, we hypothesized that Zn-InsP6 could bind to not only strontium but also to radium, and could inhibit the absorption of radium from the intestine. In in vitro binding experiments, Zn-InsP6 showed a high binding affinity for radium. In in vivo biodistribution experiments by intravenous injection of [223Ra]RaCl2 after treatment of Zn-InsP6, mice treated with Zn-InsP6 showed significantly lower bone accumulation of radioactivity (34.82 ± 1.83%Dose/g) than the mice in the non-treatment control group (40.30 ± 2.78%Dose/g) at 48 h postinjection. These results indicate that Zn-InsP6 bound radium in the intestine and inhibited the absorption of radium into the blood. Therefore, the insoluble Zn-InsP6 complex has high potential to decrease the side effects of [223Ra]RaCl2.


Asunto(s)
Absorción de Radiación , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/secundario , Intestinos/efectos de la radiación , Radio (Elemento)/administración & dosificación , Radio (Elemento)/uso terapéutico , Administración Oral , Animales , Cationes , Chlorella/metabolismo , Concentración de Iones de Hidrógeno , Masculino , Ratones , Ácido Fítico/química , Ácido Fítico/metabolismo , Radiactividad , Radioisótopos/administración & dosificación , Radioisótopos/uso terapéutico , Distribución Tisular , Zinc/farmacología
14.
Carbohydr Polym ; 241: 116269, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32507162

RESUMEN

Chitosan-based membranes are promising systems for guided bone regeneration. In this work, we used glycerylphytate as ionic crosslinker and osteinductor compound for the fabrication of chitosan membranes as supports for human mesenchymal stem cells. Three different glycerylphytate-crosslinked membranes were developed by changing the crosslinker concentration, from 2.5-10 wt-%, respect to chitosan. Physico-chemical characterization in terms of composition, morphology, and thermal behavior was further analyzed. Swelling degree, crosslinking density, and crosslinker release showed a glycerylphytate content-dependent behavior. Glycerylphytate suggested to improve osteointegration ability of chitosan surfaces by the formation of apatite-like aggregates after incubation in body simulated fluid. Stem cells cultured on the membranes increased their viability over time, and the incorporation of glycerylphytate improved osteogenic and osteoinductivity potential of chitosan by increasing calcium deposition and alkaline phosphatase (ALP) activity on cultured stem cells. These results demonstrated a potential application of glycerylphytate-crosslinked chitosan systems for promising bone tissue regeneration.


Asunto(s)
Regeneración Ósea , Quitosano/química , Reactivos de Enlaces Cruzados/química , Ácido Fítico/análogos & derivados , Ácido Fítico/química , Fosfatasa Alcalina/metabolismo , Adhesión Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Humanos , Membranas Artificiales , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ingeniería de Tejidos
15.
Carbohydr Polym ; 243: 116436, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32532389

RESUMEN

Methotrexate-loaded phytic acid-chitosan nanoparticles were synthesized by ionic gelation assisted by high-intensity sonication. The nanoparticles were characterized by particle size, polydispersity index, zeta potential (ZP) and encapsulation efficiency. Their physical stability was evaluated at 4 °C and 40 °C, whereas the in-vitro methotrexate release was assessed at pH 7.4. The data were heuristically fit to first-order, Higuchi, Peppas-Sahlin and Korsmeyer-Peppas models of release kinetics. Anticancer activity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay on HT-29 human colon adenocarcinoma cells. Physicochemical analysis showed that the nanoparticles presented positive ZP values, sizes less than <300 nm and low polydispersity, except for systems formed with low amplitude sonication. The nanoparticles exhibited an adequate physical stability and a capability to modify methotrexate release by a non-Fickian mechanism, resulting in a more pronounced cytotoxic effect than the free drug on HT-29 human colon adenocarcinoma cells.


Asunto(s)
Adenocarcinoma/patología , Antineoplásicos/farmacología , Neoplasias del Colon/patología , Portadores de Fármacos/química , Metotrexato/farmacología , Nanopartículas/química , Adenocarcinoma/tratamiento farmacológico , Quitosano/química , Neoplasias del Colon/tratamiento farmacológico , Liberación de Fármacos , Geles , Células HT29 , Humanos , Ácido Fítico/química
16.
ACS Appl Mater Interfaces ; 12(23): 26496-26508, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32406670

RESUMEN

Conductive hydrogel-based wearable strain sensors with tough, stretchable, self-recoverable, and highly sensitive properties are highly demanded for applications in electronic skin and human-machine interface. However, currently, hydrogel-based strain sensors put forward higher requirements on their biocompatibility, mechanical strength, and sensitivity. Herein, we report a poly(vinyl alcohol)/phytic acid/amino-polyhedral oligomeric silsesquioxane (PVA/PA/NH2-POSS) conductive composite hydrogel prepared via a facile freeze-thaw cycle method. Within this hydrogel, PA acts as a cross-linking agent and ionizes hydrogen ions to endow the material with ionic conductivity, while NH2-POSS acts as a second cross-linking agent by increasing the cross-linking density of the three-dimensional network structure. The effect of the content of NH2-POSS is investigated, and the composite hydrogel with 2 wt % NH2-POSS displays a uniform and dense three-dimensional (3D) network microporous structure, high conductivity of 2.41 S/m, and tensile strength and elongation at break of 361 kPa and 363%, respectively. This hydrogel is biocompatible and has demonstrated the application as a strain sensor monitoring different human movements. The assembled sensor is stretchable, self-recoverable, and highly sensitive with fast response time (220 ms) and excellent sensitivity (GF = 3.44).


Asunto(s)
Hidrogeles/química , Compuestos de Organosilicio/química , Ácido Fítico/química , Alcohol Polivinílico/química , Estrés Mecánico , Dispositivos Electrónicos Vestibles , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Línea Celular Tumoral , Conductividad Eléctrica , Humanos , Hidrogeles/síntesis química , Monitoreo Fisiológico/instrumentación , Movimiento , Porosidad , Resistencia a la Tracción
17.
Sci Rep ; 10(1): 5339, 2020 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-32210349

RESUMEN

Bouillon cubes are widely consumed and when fortified with iron could contribute in preventing iron deficiency. We report the development (part I) and evaluation (current part II) of a novel ferric phytate compound to be used as iron fortificant in condiments such as bouillon. Ferric pyrophosphate (FePP), is the compound of choice due to its high stability in foods, but has a modest absorption in humans. Our objective was to assess iron bioavailability from a novel iron fortificant consisting of ferric iron complexed with phytic acid and hydrolyzed corn protein (Fe-PA-HCP), used in bouillon with and without an inhibitory food matrix. In a randomised single blind, cross-over study, we measured iron absorption in healthy adult women (n = 22). In vitro iron bioaccessibility was assessed using a Caco-2 cell model. Iron absorption from Fe-PA-HCP was 1.5% and 4.1% in bouillon with and without inhibitory matrix, respectively. Relative iron bioavailability to FeSO4 was 2.4 times higher than from FePP in bouillon (17% vs 7%) and 5.2 times higher when consumed with the inhibitory meal (41% vs 8%). Similar results were found in vitro. Fe-PA-HCP has a higher relative bioavailability versus FePP, especially when bouillon is served with an inhibitory food matrix.


Asunto(s)
Compuestos Férricos/farmacocinética , Alimentos Fortificados , Hierro/farmacocinética , Ácido Fítico/química , Adulto , Células CACO-2 , Estudios Cruzados , Femenino , Compuestos Férricos/química , Ferritinas/sangre , Humanos , Hidrólisis , Radioisótopos de Hierro/farmacocinética , Proteínas de Vegetales Comestibles/química , Método Simple Ciego , Adulto Joven , Zea mays/química
18.
Anal Chem ; 92(2): 1940-1947, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31887020

RESUMEN

In view of the size and hydrophilicity of glycopeptides, materials having suitable channels (size-exclusion) and strong hydrophilic surface (hydrophilic interaction) are preferred to enrich the glycopeptides in biological samples. Metal-organic frameworks (MOFs) are good candidates. However, their smaller microporous channels and low chemical stability have limited the application. Herein, a facile strategy was established to construct hydrophilic mesoporous MOF via synergistic etching and surface functionalization by using phytic acid (PA). Besides, polyvinylpyrrolidone (PVP) was added during MOF synthesis to enhance the water stability of the MOF. Owing to the expanded hydrophilic mesoporous channels, the PA-modified Ce-MOF effectively and selectively captured 422 glycopeptides from 155 glycoproteins in tryptic digests of human serum (2 µL). The present work sheds light on the easy fabrication of hydrophilic mesoporous materials, and this established material holds unique advantages for glycopeptides analysis in biological samples.


Asunto(s)
Glicopéptidos/sangre , Estructuras Metalorgánicas/química , Cromatografía Liquida , Glicoproteínas/sangre , Glicoproteínas/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Estructuras Metalorgánicas/síntesis química , Ácido Fítico/química , Porosidad , Povidona/química , Proteolisis , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tripsina/química
19.
AAPS PharmSciTech ; 20(8): 319, 2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31641892

RESUMEN

Colorectal cancer has become the third most frequent reason of cancer death in men and women. Currently, natural compounds are being looked up to, for subversion and deterrence of cancers. Inositol hexaphosphate (IP6) is one such naturally occurring phosphorylated carbohydrate present in most legumes and cereals which acts as a potential antineoplastic agent and can be used effectively to prevent and treat colon carcinomas. Despite the immense potential, due to the prevalence of high charge and ability to form salts and chelates with various divalent metals, it gets excreted out quickly from the body. On reaching the colon in its original form, it can serve as an effective anticancer agent. Therefore, a suitable dosage form that can prevent the drugs from being absorbed from the upper gastrointestinal tract is required to be prepared, to target it to the colon. Thus, microspheres of IP6 using a biodegradable polymer that degrades in the colon were attempted using the solvent evaporation method. The formulation was investigated for percentage yield, encapsulation efficiency, particle size distribution modification, and release rate. Optimized formulation showed particle size of 92 ± 0.76 µm, entrapment efficiency of 67.26% ± 0.75, percent drug loading of 15.74%, and in vitro drug release 82.36 ± 0.51. The results of the in vivo study divulged that IP6 loaded pectin microspheres showed significant positive modulation of biomarker levels and restoration of colonic architecture to almost normal as observed through histopathology and scanning electron microscopy studies in DMH-induced colon tumors in Albino Wistar rats.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Ácido Fítico/química , Animales , Biomarcadores , Neoplasias del Colon/patología , Liberación de Fármacos , Femenino , Humanos , Masculino , Microesferas , Tamaño de la Partícula , Ácido Fítico/uso terapéutico , Ratas , Ratas Wistar
20.
Bioorg Chem ; 92: 103240, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31525525

RESUMEN

Phytic acid (IP6) is an ingredient in cereals and legumes, and limited amounts of this compound are considered to enter the cell and exert anti-cancer effects. These effects have been seen by studying cells treated with around 1-5 mM IP6. However, such a large amount of IP6 chelates metals and changes the pH in cell culture medium. To overcome this problem, we synthesized a prodrug of IP6 (Pro-IP6) and elucidated generation of IP6 from Pro-IP6 in cells. Cellular experiments using Pro-IP6 demonstrated selective anti-cancer effects including apoptosis and inhibition of Akt activation. Furthermore, an in vivo study using mice with adult T-cell leukemia also showed that Pro-IP6 reduced the size of the cancer. Taken together, Pro-IP6 is a useful biological tool and may lead to development of new anti-cancer drugs.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Ácido Fítico/farmacología , Profármacos/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Células Jurkat , Células K562 , Leucemia de Células T/tratamiento farmacológico , Ratones , Estructura Molecular , Ácido Fítico/química , Ácido Fítico/metabolismo , Profármacos/química , Profármacos/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
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