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2.
Int J Pharm ; 520(1-2): 21-28, 2017 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-28130197

RESUMEN

In this work, curcumin (CURC)-encapsulating nanoparticles (NPs), made up of an amphiphilic blend of poloxamers and PLGA (PPC NPs) at different polymer concentrations, were prepared by nanoprecipitation. CURC was preliminarily complexed with (2-hydroxypropyl)-ß-cyclodextrin (HPßCD) to improve its loading efficiency. The formation of host-guest complexes of CURC with HPßCD (CD-CURC) was confirmed by means of 1HNMR studies and differential scanning calorimetry (DSC). Nanoprecipitation allowed to obtain NPs with a small size (90-120nm depending on the polymer concentration), a narrow size distribution and stable in water for 30days at 4°C and in RPMI-1640 cell culture medium up to 72h at 37°C. The in vitro release of CD-CURC, sustained up to 5days, was governed mainly by a diffusive mechanism. It was also found that the produced NPs were efficiently internalized by mesothelioma cells (MSTO-211H) in the cytoplasmic space, at an extent strongly dependent on NP size and polydispesity index, therefore pointing at the importance of NP preparation method in improving their uptake.


Asunto(s)
Curcumina/química , Curcumina/farmacología , Portadores de Fármacos/química , Nanopartículas/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Precipitación Química , Curcumina/administración & dosificación , Curcumina/farmacocinética , Liberación de Fármacos , Estabilidad de Medicamentos , Humanos , Ácido Láctico/química , Nanopartículas/metabolismo , Tamaño de la Partícula , Poloxámero/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
3.
Environ Sci Pollut Res Int ; 24(2): 1270-1282, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27771877

RESUMEN

The removal of methylparaben (MP), a well-known endocrine disruptor, from aqueous solutions using polyacrylonitrile (PAN) beads has been studied under batch conditions, at room temperature and at different initial MP concentrations. The kinetic and equilibrium results have been analyzed. Kinetic modeling analysis has been carried out with three different types of adsorption models: pseudo-first-order, pseudo-second-order, and Elovich model. Kinetic data analysis indicated that the adsorption was a second-order process. The MP adsorption by PAN was also quantitatively evaluated by using the equilibrium adsorption isotherm models of Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin and the applicability of the respective isotherm equations has been compared through the correlation coefficients. Adsorption data resulted well fitted by the Freundlich isotherm model. Data of MP adsorption have also been used to test different adsorption diffusion models. The diffusion rate equations inside particulate of Dumwald-Wagner and the intraparticle diffusion model have been used to calculate the diffusion rate. The actual rate-controlling step involved in the MB adsorption process was determined. The kinetic expression by Boyd gave the right indications. All together, our results indicate that PAN beads are a useful tool to remediate water bodies polluted by endocrine disruptors.


Asunto(s)
Resinas Acrílicas/química , Parabenos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Difusión , Concentración de Iones de Hidrógeno , Cinética , Soluciones , Termodinámica
4.
Mol Cell Endocrinol ; 422: 74-83, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26604029

RESUMEN

In recent years, impaired fertility and endometrium related diseases are increased. Many evidences suggest that environmental pollution might be considered a risk factor for endometrial physiopathology. Among environmental pollutants, endocrine disrupting chemicals (EDCs) act on endocrine system, causing hormonal imbalance which, in turn, leads to female and male reproductive dysfunctions. In this work, we studied the effects of triclosan (TCL) and bisphenol A (BPA), two widespread EDCs, on human endometrial stromal cells (ESCs), derived from endometrial biopsies from woman not affected by endometriosis. Cell proliferation, cell cycle, migration and decidualization mechanisms were investigated. Treatments have been performed with both the EDCs separately or in presence and in absence of progesterone used as decidualization stimulus. Both TCL and BPA did not affect cell proliferation, but they arrested ESCs at G2/M phase of cell cycle enhancing cell migration. TCL and BPA also increased gene expression and protein levels of some decidualization markers, such as insulin growth factor binding protein 1 (IGFBP1) and prolactin (PRL), amplifying the effect of progesterone alone. All together, our data strongly suggest that TCL and BPA might alter human endometrium physiology so affecting fertility and pregnancy outcome.


Asunto(s)
Decidua/citología , Disruptores Endocrinos/efectos adversos , Endometrio/citología , Células del Estroma/efectos de los fármacos , Triclosán/efectos adversos , Adulto , Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Decidua/metabolismo , Endometrio/efectos de los fármacos , Endometrio/metabolismo , Femenino , Humanos , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Persona de Mediana Edad , Progesterona/farmacología , Prolactina/genética , Prolactina/metabolismo , Células del Estroma/citología , Células del Estroma/metabolismo , Regulación hacia Arriba
5.
J Mol Endocrinol ; 54(3): 289-303, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25878060

RESUMEN

Bisphenol A (BPA) is a xenobiotic endocrine-disrupting chemical. In vitro and in vivo studies have indicated that BPA alters endocrine-metabolic pathways in adipose tissue, which increases the risk of metabolic disorders and obesity. BPA can affect adipose tissue and increase fat cell numbers or sizes by regulating the expression of the genes that are directly involved in metabolic homeostasis and obesity. Several studies performed in animal models have accounted for an obesogen role of BPA, but its effects on human adipocytes - especially in children - have been poorly investigated. The aim of this study is to understand the molecular mechanisms by which environmentally relevant doses of BPA can interfere with the canonical endocrine function that regulates metabolism in mature human adipocytes from prepubertal, non-obese children. BPA can act as an estrogen agonist or antagonist depending on the physiological context. To identify the molecular signatures associated with metabolism, transcriptional modifications of mature adipocytes from prepubertal children exposed to estrogen were evaluated by means of microarray analysis. The analysis of deregulated genes associated with metabolic disorders allowed us to identify a small group of genes that are expressed in an opposite manner from that of adipocytes treated with BPA. In particular, we found that BPA increases the expression of pro-inflammatory cytokines and the expression of FABP4 and CD36, two genes involved in lipid metabolism. In addition, BPA decreases the expression of PCSK1, a gene involved in insulin production. These results indicate that exposure to BPA may be an important risk factor for developing metabolic disorders that are involved in childhood metabolism dysregulation.


Asunto(s)
Adipocitos/metabolismo , Compuestos de Bencidrilo/toxicidad , Disruptores Endocrinos/toxicidad , Fenoles/toxicidad , Transcriptoma/efectos de los fármacos , Adipocitos/efectos de los fármacos , Células Cultivadas , Niño , Estradiol/farmacología , Femenino , Humanos , Insulina/biosíntesis , Insulina/metabolismo , Secreción de Insulina , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/patología
6.
Eur J Pharm Biopharm ; 93: 37-45, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25794477

RESUMEN

The pharmacological potential of curcumin (CURC) is severely restricted because of its low water solubility/absorption, short half-life and poor bioavailability. To overcome these issues, CURC-loaded nanoparticles (NPs) were produced by a double emulsion technique. In particular, NPs were made up of an amphiphilic blend of poloxamers and PLGA to confer stealth properties to the NPs to take advantage of the enhanced permeability and retention (EPR) effect. Different surface properties of NPs made up of bare PLGA and PLGA/poloxamer blend were confirmed by the different interactions of these NPs with serum proteins and also by their ability to be internalized by mesothelioma cell line. The uptake of PLGA/poloxamer NPs induces a persistent block in G0/G1 phase of the cell cycle up to 72 h, thus overcoming the drug tolerance phenomenon, normally evidenced with free CURC.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Curcumina/farmacología , Portadores de Fármacos , Ácido Láctico/química , Mesotelioma/tratamiento farmacológico , Nanopartículas , Poloxámero/química , Ácido Poliglicólico/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Química Farmacéutica , Curcumina/química , Curcumina/metabolismo , Estabilidad de Medicamentos , Tolerancia a Medicamentos , Humanos , Cinética , Mesotelioma/patología , Nanomedicina , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Unión Proteica , Solubilidad , Propiedades de Superficie , Tecnología Farmacéutica/métodos
7.
J Hazard Mater ; 291: 129-35, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-25781217

RESUMEN

Serratia rubidiae, Pseudomonas aeruginosa and Escherichia coli K12 have been studied for their ability of Bisphenol A removal from aqueous systems and biofilm formation on activated granule carbon. Mathematical equations for biodegradation process have been elaborated and discussed. P. aeruginosa was found the best strain to be employed in the process of Bisphenol A removal. The yield in BPA removal of a P. aeruginosa biofilm grown on GAC and operating in a fluidized bed reactor has been evaluated. The results confirm the usefulness in using biological activated carbon (BAC process) to remove phenol compounds from aqueous systems.


Asunto(s)
Compuestos de Bencidrilo/aislamiento & purificación , Reactores Biológicos/microbiología , Fenoles/aislamiento & purificación , Pseudomonas aeruginosa/metabolismo , Adsorción , Biodegradación Ambiental , Biopelículas , Carbono , Carbón Orgánico/química , Contaminantes del Agua/aislamiento & purificación
8.
Chemosphere ; 119 Suppl: S115-23, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25011641

RESUMEN

The performance of S2O8(2-)/UV-C and H2O2/UV-C treatments was investigated for the degradation and detoxification of Bisphenol A (BPA). The acute toxicity of BPA and its degradation products was examined with the Vibrio fischeri bioassay, whereas changes in estrogenic activity were followed with the Yeast Estrogen Screen (YES) assay. LC and LC-MS/MS analyses were conducted to determine degradation products evolving during photochemical treatment. In addition, BPA-spiked real freshwater samples were also subjected to S2O8(2-)/UV-C and H2O2/UV-C treatment to study the effect of a real water matrix on BPA removal and detoxification rates. BPA removal in pure water was very fast (⩽7 min) and complete via both H2O2/UV-C and S2O8(2-)/UV-C treatment, accompanied with rapid and significant mineralization rates ranging between 70% and 85%. V.fischeri bioassay results indicated that degradation products being more toxic than BPA were formed at the initial stages of H2O2/UV-C whereas a rapid and steady reduction in toxicity was observed during S2O8(2-)/UV-C treatment in pure water. UV-C treatment products exhibited a higher estrogenic activity than the original BPA solution while the estrogenicity of BPA was completely removed during H2O2/UV-C and S2O8(2-)/UV-C treatments parallel to its degradation. 3-methylbenzoic and 4-sulfobenzoic acids, as well as the ring opening products fumaric, succinic and oxalic acids could be identified as degradation products. BPA degradation required extended treatment periods (>20 min) and TOC removals were considerably retarded (by 40%) in the raw freshwater matrix most probably due to its natural organic matter content (TOC=5.1 mg L(-1)). H2O2/UV-C and S2O8(2-)/UV-C treatment in raw freshwater did not result in toxic degradation products.


Asunto(s)
Compuestos de Bencidrilo , Estrógenos , Peróxido de Hidrógeno/química , Fenoles , Compuestos de Sodio/química , Sulfatos/química , Rayos Ultravioleta , Contaminantes Químicos del Agua , Aliivibrio fischeri/efectos de los fármacos , Aliivibrio fischeri/metabolismo , Compuestos de Bencidrilo/química , Compuestos de Bencidrilo/efectos de la radiación , Compuestos de Bencidrilo/toxicidad , Ácidos Carboxílicos/química , Cromatografía Liquida , Receptor alfa de Estrógeno/metabolismo , Estrógenos/química , Estrógenos/efectos de la radiación , Estrógenos/toxicidad , Agua Dulce , Oxidantes/química , Fenoles/química , Fenoles/efectos de la radiación , Fenoles/toxicidad , Saccharomyces cerevisiae/genética , Espectrometría de Masas en Tándem , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua/métodos
9.
Food Chem ; 160: 157-64, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24799222

RESUMEN

A method based on solid-phase extraction followed by liquid chromatography, coupled to UV-visible and fluorescence spectrophotometry, has been developed for determination of bisphenol A (BPA) in canned tomatoes. The limit of quantification (LOQ) of the procedure used is 0.03 µM (0.26 µg BPA/kg tomato). For each of three different tomato based products (peeled, cherry and concentrated paste), 16 samples belonging to six commercial brands, retailed in Italian markets, were tested for migration of BPA epoxy-coating cans. All the tomato samples exhibited migration levels below 0.4 µg/kg, while samples subjected to heating process and/or can's damage by denting, exhibited a significant increase in the migration levels. In any case, no sample contained BPA exceeding the European Union limit for migration, set at 600 µg/kg of food. By comparing the results for each brand, no relevant difference in BPA concentration was found depending on the kind of tomato products.


Asunto(s)
Compuestos de Bencidrilo/análisis , Conservación de Alimentos/métodos , Alimentos en Conserva/análisis , Fenoles/análisis , Solanum lycopersicum/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Unión Europea , Contaminación de Alimentos/análisis , Italia , Concentración Máxima Admisible , Extracción en Fase Sólida/métodos , Temperatura
10.
Sci Total Environ ; 470-471: 1272-80, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24252200

RESUMEN

The capacity of a hybrid constructed wetland (CW) system consisting of two vertical flow (VF) CWs working alternatively (3m(2)), one horizontal flow (HF) CW (2m(2)) and one surface flow (FWS) CW (2m(2)) in series to eliminate 13 emerging organic contaminants (EOCs) under three different hydraulic loading rates (HLRs) (0.06, 0.13 and 0.18 m d(-1) considering the area of the two VF beds) was studied through a continuous injection experiment. General toxicity, dioxin-like activity, antimicrobial activity and estrogenicity were also measured under the highest hydraulic loading rate. The hybrid system was highly efficient on the removal of total injected EOCs (except for antibiotics, 43 ± 32%) at all three HLRs (87 ± 10%). The removal efficiency in the hybrid CW system showed to decrease as the HLR increased for most compounds. The VF wetlands removed most of the injected EOCs more efficiently than the other two CWs, which was attributable to the predominant aerobic degradation pathways of the VF beds (70 ± 21%). General toxicity was reduced up to 90% by the VF beds. Estrogenicity and dioxin-like activity were similarly reduced by the VF and the HF wetlands, whereas antimicrobial activity was mainly removed by the FWS wetland. Bearing this in mind, this injection study has demonstrated that the use of hybrid CW systems is a suitable wastewater technology for removing EOCs and toxicity even at high HLRs.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/toxicidad , Humedales , Biodegradación Ambiental , Movimientos del Agua , Contaminantes Químicos del Agua/análisis
11.
J Hazard Mater ; 248-249: 337-46, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23416477

RESUMEN

A fluidized bed reactor, filled with laccase-based beads, has been employed to bioremediate aqueous solutions polluted by endocrine disruptors belonging to the alkylphenols (APs) class. In particular Octylphenol and Nonylphenol have been studied. The catalytic activity of free and immobilized laccase from Trametes versicolor has been characterized as a function of pH, temperature and substrate concentration in the reaction medium. In view of practical applications for each substrate concentration the removal efficiency (RE), the time to halve the initial concentration (τ50), and the tc=0, i.e. the time to reach complete pollutant removal, have been calculated. The immobilized laccase exhibited a lower affinity for octylphenol (Km=1.11mM) than for Nonylphenol (Km=0.72mM), but all the other parameters of applicative interest resulted more significant for octylphenol. For example, the times to reach the complete removal of octylphenol compared to those for nonylphenol at the same concentration is shorter of about 15% (at low concentrations) up to 40% (at high concentrations). The study of cell proliferation with MPP89 cells, a human mesothelioma cell line, and the assay with the YES test indicated the loss of estrogenic activity of the APs solutions after laccase treatment.


Asunto(s)
Estrógenos/química , Lacasa/química , Fenoles/química , Contaminantes Químicos del Agua/química , Reactores Biológicos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Disruptores Endocrinos/química , Receptor alfa de Estrógeno/genética , Genes Reporteros , Humanos , Elementos de Respuesta , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Soluciones , Trametes/enzimología , Contaminantes Químicos del Agua/farmacología , Purificación del Agua
12.
Biodegradation ; 22(3): 673-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21125313

RESUMEN

The biodegradation of waters polluted by some bisphenols, endowed with endocrine activity, has been studied by means of laccase or tyrosinase immobilized on polyacrylonitrile (PAN) beads. Bisphenol A (BPA), Bisphenol B (BPB), Bisphenol F (BPF) and Tetrachlorobisphenol A (TCBPA) have been used. The laccase-PAN beads system has been characterized as a function of pH, temperature and substrate concentration. The biochemical parameters so obtained have been compared with those of the free enzyme to evidence the modification induced by the immobilization process. Once characterized, the laccase-PAN beads have been employed in a fluidized bed reactor to determine for each of the four bisphenols the degradation rate constant (k); the τ(50), i.e., the time to obtain the 50% of degradation, and the removal efficiency (RE(90)) after 90 min of enzyme treatment. The same parameters have been measured for each of the four pollutants with the same fluidized bed bioreactor loaded with tyrosinase-PAN beads. The internal comparison, i.e., in each of the two catalytic systems, has shown that both enzymes exhibit a removal efficiency in the following order BPF>BPA>BPB>TCBPA. The external comparison, i.e., the comparison between the two catalytic system, has shown that the catalytic power of laccase were higher than that of tyrosinase. The operational stability of both catalytic systems resulted excellent, since they maintained more than 80% of the initial activity after 30 days of work.


Asunto(s)
Enzimas Inmovilizadas/química , Proteínas Fúngicas/química , Lacasa/química , Monofenol Monooxigenasa/química , Fenoles/química , Resinas Acrílicas/química , Agaricales/enzimología , Compuestos de Bencidrilo , Biodegradación Ambiental , Cinética , Trametes/enzimología
13.
Gen Comp Endocrinol ; 168(3): 318-25, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20350546

RESUMEN

Endometriosis is a chronic gynecological disease characterized by the growth of endometrial tissue outside the uterine cavity. Exposure to endocrine disruptors during critical period of development causes long-lasting effects, being the genital system one of the targets. This study describes the effects on female genital system caused by developmental exposure to the endocrine-disrupting chemical bisphenol A (BPA) during pre- and peri-natal development in mice. To this end, timed pregnant Balb-C mice were treated from day 1 of gestation to 7 days after delivery with BPA (100, or 1000 microg/kg/day). After delivery, pups were held for 3 months; then, pelvic organs were analyzed in their entirety and livers of both pups and moms were studied for the presence of BPA. We found in the adipose tissue surrounding the genital tracts of a consistent number of treated animals, endometriosis-like structure with the presence of both glands and stroma and expressing both estrogen receptor and HOXA-10. Moreover, cystic ovaries, adenomatous hyperplasia with cystic endometrial hyperplasia and atypical hyperplasia were significantly more frequent in treated animals respect to the controls. Finally, BPA was found in the livers of exposed moms and female offspring. In conclusion, we describe for the first time an endometriosis-like phenotype in mice, elicited by pre-natal exposition to BPA. This observation may induce to thoroughly reconsider the pathogenesis and treatment of endometriosis, considering the high incidence of endometriosis and the problems caused by associated infertility.


Asunto(s)
Endometriosis/inducido químicamente , Endometriosis/etiología , Fenoles/toxicidad , Animales , Compuestos de Bencidrilo , Endometriosis/metabolismo , Femenino , Genitales Femeninos/efectos de los fármacos , Genitales Femeninos/embriología , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Fenoles/administración & dosificación , Embarazo , Efectos Tardíos de la Exposición Prenatal , Útero/efectos de los fármacos , Útero/embriología
14.
J Transl Med ; 7: 48, 2009 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-19538739

RESUMEN

BACKGROUND: BPA (bisphenol A or 2,2-bis(4-hydroxy-phenol)propane) is present in the manufacture of polycarbonate plastic and epoxy resins, which can be used in impact-resistant safety equipment and baby bottles, as protective coatings inside metal food containers, and as composites and sealants in dentistry. Recently, attention has focused on the estrogen-like and carcinogenic adverse effects of BPA. Thus, it is necessary to investigate the cytotoxicity and apoptosis-inducing activity of this compound. METHODS: Cell cycle, apoptosis and differentiation analyses; western blots. RESULTS: BPA is able to induce cell cycle arrest and apoptosis in three different acute myeloid leukemias. Although some granulocytic differentiation concomitantly occurred in NB4 cells upon BPA treatment, the major action was the induction of apoptosis. BPA mediated apoptosis was caspase dependent and occurred by activation of extrinsic and intrinsic cell death pathways modulating both FAS and TRAIL and by inducing BAD phosphorylation in NB4 cells. Finally, also non genomic actions such as the early decrease of both ERK and AKT phosphorylation were induced by BPA thus indicating that a complex intersection of regulations occur for the apoptotic action of BPA. CONCLUSION: BPA is able to induce apoptosis in leukemia cells via caspase activation and involvement of both intrinsic and extrinsic pathways of apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Leucemia Mieloide Aguda/patología , Fenoles/farmacología , Compuestos de Bencidrilo , Antígeno CD11c/metabolismo , Caspasas/metabolismo , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Factores de Tiempo , Células Tumorales Cultivadas , Proteína Letal Asociada a bcl/metabolismo , Receptor fas/metabolismo
15.
J Agric Food Chem ; 56(23): 11471-7, 2008 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-18986151

RESUMEN

The catalytic behavior of a mixture of pectic enzymes, covalently immobilized on different supports (glass microspheres, nylon 6/6 pellets, and PAN beads), was analyzed with a pectin aqueous solution that simulates apple juice. The following parameters were investigated: the rate constant at which pectin hydrolysis is conducted, the time (tau(50)) in which the reduction of 50% of the initial viscosity is reached, and the time (tau(comp,dep)) required to obtain complete depectinization. The best catalytic system was proven to be PAN beads, and their pH and temperature behavior were determined. The yields of two bed reactors, packed or fluidized, using the catalytic PAN beads, were compared to the circulation flow rate of real apple juice. The experimental conditions were as follows: pH 4.0, T = 50 degrees C, and beads volume = 20 cm(3). The initial pectin concentration was the one that was present in our apple juice sample. No differences were observed at low circulation rates, while at higher recirculation rates, the time required to obtain complete pectin hydrolysis into the fluidized reactor was found to be 0.25 times smaller than in the packed bed reactor: 131 min for the packed reactors and 41 min for the fluidized reactors.


Asunto(s)
Bebidas/análisis , Reactores Biológicos , Enzimas Inmovilizadas/química , Industria de Procesamiento de Alimentos , Malus/química , Poligalacturonasa/química , Adsorción , Catálisis , Cinética , Pectinas/química , Viscosidad
16.
IUBMB Life ; 60(12): 843-52, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18767177

RESUMEN

A wide variety of environmental contaminants exert estrogenic actions in wildlife, laboratory animals, and in human beings through binding to nuclear estrogen receptors (ERs). Here, the mechanism(s) of bisphenol A (BPA) to induce cell proliferation and the occurrence of its bioremediation by treatment with laccase are reported. BPA, highly present in natural world and considered as a model of environmental estrogen action complexity, promotes human cancer cell proliferation via ERalpha-dependent signal transduction pathways. Similar to 17beta-estradiol, BPA increases the phosphorylation of both extracellular regulated kinase and AKT. Specific inhibitors of these kinase completely block the BPA effect on cancer cell proliferation. Notably, high BPA concentrations (i.e., 0.1 and 1 mM) are cytotoxic even in ERalpha-devoid cancer cells, indicating that an ERalpha-independent mechanism participates to BPA-induced cytotoxicity. On the other hand, BPA oxidation by laccase impairs the binding of this environmental estrogen to ERalpha loosing at all ERalpha-dependent effect on cancer cell proliferation. Moreover, the laccase-catalyzed oxidation of BPA reduces the BPA cytotoxic effect. Thus, laccase appears to impair BPA action(s), representing an invaluable bioremediation enzyme.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Receptor alfa de Estrógeno/metabolismo , Estrógenos no Esteroides/farmacología , Lacasa/metabolismo , Fenoles/farmacología , Transducción de Señal/efectos de los fármacos , Compuestos de Bencidrilo , Células HeLa/efectos de los fármacos , Humanos , Immunoblotting , Espectrometría de Masas , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Neoplasias/patología , Fosforilación/efectos de los fármacos , Plásmidos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transfección
17.
Int J Biochem Cell Biol ; 39(10): 1902-14, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17604209

RESUMEN

Curative properties of some medicinal plants such as the Feijoa sellowiana Bert. (Myrtaceae), have been often claimed, although the corresponding molecular mechanism(s) remain elusive. We report here that the Feijoa acetonic extract exerts anti-cancer activities on solid and hematological cancer cells. Feijoa extract did not show toxic effects on normal myeloid progenitors thus displaying a tumor-selective activity. In the Feijoa acetonic extract, fractionation and subsequent purification and analyses identified Flavone as the active component. Flavone induces apoptosis which is accompanied by caspase activation and p16, p21 and TRAIL over-expression in human myeloid leukemia cells. Use of ex vivo myeloid leukemia patients blasts confirms that both the full acetonic Feijoa extract and its derived Flavone are able to induce apoptosis. In both cell lines and myeloid leukemia patients blasts the apoptotic activity of Feijoa extract and Flavone is accompanied by increase of histone and non-histone acetylation levels and by HDAC inhibition. Our findings show for the first time that the Feijoa apoptotic active principle is the Flavone and that this activity correlates with the induction of HDAC inhibition, supporting the hypothesis of its epigenetic pro-apoptotic regulation in cancer systems.


Asunto(s)
Feijoa/química , Flavonoides/farmacología , Flavonoides/uso terapéutico , Inhibidores de Histona Desacetilasas , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Flavonas , Células HeLa , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Modelos Biológicos , Neoplasias/patología , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Células Tumorales Cultivadas , Células U937
18.
Recenti Prog Med ; 96(10): 474-7, 2005 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-16491768

RESUMEN

The prodromal stage of atherosclerotic lesions is already formed during human fetal development. The presence of infections during childhood may increase synergistically the progression of atherogenesis. After delivery, especially those children exposed to severe maternal hypercholesterolemia should be followed up for the onset and development of acute and chronic infections and be included in clinical and noninvasive examinations of vascular function.


Asunto(s)
Aterosclerosis/etiología , Endotelio Vascular/fisiopatología , Infecciones/complicaciones , Niño , Preescolar , Enfermedad Crónica , Endotelio Vascular/microbiología , Endotelio Vascular/patología , Femenino , Desarrollo Fetal , Humanos , Hipercolesterolemia/complicaciones , Infecciones/patología , Infecciones/fisiopatología , Intercambio Materno-Fetal , Embarazo , Factores de Riesgo
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