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1.
Phytochemistry ; 214: 113789, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37482264

RESUMEN

In botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage in human health, we introduced the DESIGNER approach of Depleting and Enriching Selective Ingredients to Generate Normalized Extract Resources. The present study applied this concept to clinical Red Clover Extract (RCE) and combined phytochemical and biological methodology to help rationalize the utility of RCE supplements for symptom management in postmenopausal women. Previous work has demonstrated that RCE reduces estrogen detoxification pathways in breast cancer cells (MCF-7) and, thus, may serve to negatively affect estrogen metabolism-induced chemical carcinogenesis. Clinical RCE contains ca. 30% of biochanin A and formononetin, which potentially mask activities of less abundant compounds. These two isoflavonoids are aryl hydrocarbon receptor (AhR) agonists that activate P450 1A1, responsible for estrogen detoxification, and P450 1B1, producing genotoxic estrogen metabolites in female breast cells. Clinical RCE also contains the potent phytoestrogen, genistein, that downregulates P450 1A1, thereby reducing estrogen detoxification. To identify less abundant bioactive constituents, countercurrent separation (CCS) of a clinical RCE yielded selective lipophilic to hydrophilic metabolites in six enriched DESIGNER fractions (DFs 01-06). Unlike solid-phase chromatography, CCS prevented any potential loss of minor constituents or residual complexity (RC) and enabled the polarity-based enrichment of certain constituents. Systematic analysis of estrogen detoxification pathways (ERα-degradation, AhR activation, CYP1A1/CYP1B1 induction and activity) of the DFs uncovered masked bioactivity of minor/less abundant constituents including irilone. These data will allow the optimization of RCE with respect to estrogen detoxification properties. The DFs revealed distinct biological activities between less abundant bioactives. The present results can inspire future carefully designed extracts with phytochemical profiles that are optimized to increase in estrogen detoxification pathways and, thereby, promote resilience in women with high-risk for breast cancer. The DESIGNER approach helps to establish links between complex chemical makeup, botanical safety and possible efficacy parameters, yields candidate DFs for (pre)clinical studies, and reveals the contribution of minor phytoconstituents to the overall safety and bioactivity of botanicals, such as resilience promoting activities relevant to women's health.


Asunto(s)
Neoplasias de la Mama , Isoflavonas , Trifolium , Femenino , Humanos , Trifolium/química , Trifolium/metabolismo , Isoflavonas/farmacología , Isoflavonas/metabolismo , Estrógenos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Neoplasias de la Mama/tratamiento farmacológico
2.
Sci Rep ; 13(1): 8734, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37253812

RESUMEN

Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. Natural products such as hops (Humulus lupulus) and three pharmacopeial licorice (Glycyrrhiza) species have demonstrated estrogenic and chemopreventive properties, but little is known regarding their effects on aromatase expression and activity as well as pro-proliferation pathways in human breast tissue. We show that Gycyrrhiza inflata (GI) has the highest aromatase inhibition potency among these plant extracts. Moreover, phytoestrogens such as liquiritigenin which is common in all licorice species have potent aromatase inhibitory activity, which is further supported by computational docking of their structures in the binding pocket of aromatase. In addition, GI extract and liquiritigenin suppress aromatase expression in the breast tissue of high-risk postmenopausal women. Although liquiritigenin has estrogenic effects in vitro, with preferential activity through estrogen receptor (ER)-ß, it reduces estradiol-induced uterine growth in vivo. It downregulates RNA translation, protein biosynthesis, and metabolism in high-risk women's breast tissue. Finally, it reduces the rate of MCF-7 cell proliferation, with repeated dosing. Collectively, these data suggest that liquiritigenin has breast cancer prevention potential for high-risk postmenopausal women.


Asunto(s)
Neoplasias de la Mama , Glycyrrhiza , Femenino , Humanos , Neoplasias de la Mama/prevención & control , Neoplasias de la Mama/metabolismo , Aromatasa/metabolismo , Inhibidores de la Aromatasa/farmacología , Estrógenos/metabolismo , Glycyrrhiza/química , Receptor beta de Estrógeno/metabolismo , Biosíntesis de Proteínas
3.
ACS Appl Mater Interfaces ; 14(45): 50543-50556, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36331290

RESUMEN

The COVID-19 pandemic has revealed the importance of the detection of airborne pathogens. Here, we present composite air filters featuring a bioinspired liquid coating that facilitates the removal of captured aerosolized bacteria and viruses for further analysis. We tested three types of air filters: commercial polytetrafluoroethylene (PTFE), which is well known for creating stable liquid coatings, commercial high-efficiency particulate air (HEPA) filters, which are widely used, and in-house-manufactured cellulose nanofiber mats (CNFMs), which are made from sustainable materials. All filters were coated with omniphobic fluorinated liquid to maximize the release of pathogens. We found that coating both the PTFE and HEPA filters with liquid improved the rate at which Escherichia coli was recovered using a physical removal process compared to uncoated controls. Notably, the coated HEPA filters also increased the total number of recovered cells by 57%. Coating the CNFM filters did not improve either the rate of release or the total number of captured cells. The most promising materials, the liquid-coated HEPA, filters were then evaluated for their ability to facilitate the removal of pathogenic viruses via a chemical removal process. Recovery of infectious JC polyomavirus, a nonenveloped virus that attacks the central nervous system, was increased by 92% over uncoated controls; however, there was no significant difference in the total amount of genomic material recovered compared to that of controls. In contrast, significantly more genomic material was recovered for SARS-CoV-2, the airborne, enveloped virus, which causes COVID-19, from liquid-coated filters. Although the amount of infectious SARS-CoV-2 recovered was 58% higher, these results were not significantly different from uncoated filters due to high variability. These results suggest that the efficient recovery of airborne pathogens from liquid-coated filters could improve air sampling efforts, enhancing biosurveillance and global pathogen early warning.


Asunto(s)
Filtros de Aire , COVID-19 , Virus , Humanos , Pandemias , SARS-CoV-2 , COVID-19/prevención & control , Bacterias , Polvo , Politetrafluoroetileno
4.
ACS Appl Mater Interfaces ; 12(51): 57431-57440, 2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33306341

RESUMEN

Filamentous fungi have been considered as candidates to replace petroleum-based adhesives and plastics in novel composite material production, particularly those containing lignocellulosic materials. However, the nature of the role of surface mycelium in the adhesion between lignocellulosic composite components is not well-known. The current study investigated the functionality of surface mycelium for wood bonding by incubating Trametes versicolor on yellow birch veneers and compared the lap-shear strengths after hot-pressing to evaluate if the presence of surface mycelium can improve the interface between two wood layers and consequently improve bonding. We found that the lap-shear strength of the samples was enhanced by the increase of surface mycelium coverage up to 8 days of incubation (up to 1.74 MPa) without a significant wood weight loss. We provide evidence that the bottom surface of the mycelium layer is more hydrophilic, contains more small-scale filamentous structure and contains more functional groups, resulting in better bonding with wood than the top surface. These observations confirm and highlight the functionality of the surface mycelium layer for wood bonding and provide useful information for future developments in fully biobased composites manufacturing.


Asunto(s)
Adhesivos/química , Micelio/química , Madera/química , Adhesivos/metabolismo , Ensayo de Materiales , Micelio/metabolismo , Polyporaceae/metabolismo , Resistencia al Corte , Propiedades de Superficie , Madera/metabolismo , Madera/microbiología
5.
Chem Res Toxicol ; 33(11): 2793-2803, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32986415

RESUMEN

Botanical dietary supplements (BDS) containing hops are sold as women's health supplements due to the potent hop phytoestrogen, 8-prenylnaringenin (8-PN), and the cytoprotective chalcone, xanthohumol. Previous studies have shown a standardized hop extract to beneficially influence chemical estrogen carcinogenesis in vitro by fostering detoxified 2-hydroxylation over genotoxic 4-hydroxylation estrogen metabolism. In this study, hop extract and its bioactive compounds were investigated for its mechanism of action within the chemical estrogen carcinogenesis pathway, which is mainly mediated through the 4-hydroxylation pathway catalyzed by CYP1B1 that can form gentoxic quinones. Aryl hydrocarbon receptor (AhR) agonists induce CYP1A1 and CYP1B1, while estrogen receptor alpha (ERα) inhibits transcription of CYP1A1, the enzyme responsible for 2-hydroxylated estrogens and the estrogen detoxification pathway. An In-Cell Western MCF-7 cell assay revealed hop extract and 6-prenylnaringenin (6-PN) degraded ERα via an AhR-dependent mechanism. Reverse transcription PCR and xenobiotic response element luciferase assays showed hop extract and 6-PN-mediated activation of AhR and induction of CYP1A1. A reduction in estrogen-mediated DNA (cytosine-5)-methyltransferase 1 (DNMT1) downregulation of CYP1A1 accompanied this activity in a chromatin immunoprecipitation assay. Ultimately, hop extract and 6-PN induced preferential metabolism of estrogens to their detoxified form in vitro. These results suggest that the standardized hop extract and 6-PN activate AhR to attenuate epigenetic inhibition of CYP1A1 through degradation of ERα, ultimately increasing 2-hydroxylated estrogens. A new mechanism of action rationalizes the positive influence of hop BDS and 6-PN on oxidative estrogen metabolism in vitro and, thus, potentially on chemical estrogen carcinogenesis. The findings underscore the importance of elucidating various biological mechanisms of action and standardizing BDS to multiple phytoconstituents for optimal resilience promoting properties.


Asunto(s)
Citocromo P-450 CYP1A1/antagonistas & inhibidores , Regulación hacia Abajo/efectos de los fármacos , Receptor alfa de Estrógeno/antagonistas & inhibidores , Estrógenos/efectos adversos , Flavonoides/farmacología , Humulus/química , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Flavonoides/química , Flavonoides/aislamiento & purificación , Humanos , Células Tumorales Cultivadas
6.
J Agric Food Chem ; 68(39): 10651-10663, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32945668

RESUMEN

Many botanicals used for women's health contain estrogenic (iso)flavonoids. The literature suggests that estrogen receptor beta (ERß) activity can counterbalance estrogen receptor alpha (ERα)-mediated proliferation, thus providing a better safety profile. A structure-activity relationship study of (iso)flavonoids was conducted to identify ERß-preferential structures, overall estrogenic activity, and ER subtype estrogenic activity of botanicals containing these (iso)flavonoids. Results showed that flavonoids with prenylation on C8 position increased estrogenic activity. C8-prenylated flavonoids with C2-C3 unsaturation resulted in increased ERß potency and selectivity [e.g., 8-prenylapigenin (8-PA), EC50 (ERß): 0.0035 ± 0.00040 µM], whereas 4'-methoxy or C3 hydroxy groups reduced activity [e.g., icaritin, EC50 (ERß): 1.7 ± 0.70 µM]. However, nonprenylated and C2-C3 unsaturated isoflavonoids showed increased ERß estrogenic activity [e.g., genistein, EC50 (ERß): 0.0022 ± 0.0004 µM]. Licorice (Glycyrrhiza inflata, [EC50 (ERα): 1.1 ± 0.20; (ERß): 0.60 ± 0.20 µg/mL], containing 8-PA, and red clover [EC50 (ERα): 1.8 ± 0.20; (ERß): 0.45 ± 0.10 µg/mL], with genistein, showed ERß-preferential activity as opposed to hops [EC50 (ERα): 0.030 ± 0.010; (ERß): 0.50 ± 0.050 µg/mL] and Epimedium sagittatum [EC50 (ERα): 3.2 ± 0.20; (ERß): 2.5 ± 0.090 µg/mL], containing 8-prenylnaringenin and icaritin, respectively. Botanicals with ERß-preferential flavonoids could plausibly contribute to ERß-protective benefits in menopausal women.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Epimedium/química , Receptor alfa de Estrógeno/química , Receptor beta de Estrógeno/química , Estrógenos/química , Estrógenos/metabolismo , Glycyrrhiza/química , Humanos , Humulus/química , Prenilación , Relación Estructura-Actividad
7.
Biointerphases ; 15(3): 030801, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32486650

RESUMEN

The most common bulk acoustic wave device used in biosensing applications is the quartz crystal microbalance (QCM), in which a resonant pure shear acoustic wave is excited via electrodes on both major faces of a thin AT-cut quartz plate. For biosensing, the QCM is used to detect the capture of a target by a target-capture film. The sensitivity of the QCM is typically based solely on the detection of mechanical property changes, as electrical property change detection is limited by the electrode on its sensing surface. A modification of the QCM called the lateral field excited (LFE) QCM (LFE-QCM) has been developed with a bare sensing surface as both electrodes are now on a single face of the quartz plate. Compared to the QCM, the LFE-QCM exhibits significantly higher sensitivity to both electrical and mechanical property changes. This paper presents theoretical and experimental aspects of LFE-QCMs. In particular, the presence and strength of the usual and newfound LFE-QCM modes depend on the electrical properties of the film and/or sensing environment. This work also presents examples of experimental setups for measuring the response of an LFE-QCM, followed by results of LFE-QCMs used to detect liquid electrical and mechanical properties, chemical targets, and biological targets. Finally, details are given about the attachment of various target-capture films to the LFE-QCM surface to capture biomarkers associated with diseases such as cancer.


Asunto(s)
Técnicas Biosensibles , Tecnicas de Microbalanza del Cristal de Cuarzo , Acústica , Biomarcadores/análisis , Conductividad Eléctrica , Modelos Teóricos
8.
Cancer Prev Res (Phila) ; 11(12): 819-830, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30287522

RESUMEN

Women are increasingly using botanical dietary supplements (BDS) to reduce menopausal hot flashes. Although licorice (Glycyrrhiza sp.) is one of the frequently used ingredients in BDS, the exact plant species is often not identified. We previously showed that in breast epithelial cells (MCF-10A), Glycyrrhiza glabra (GG) and G. inflata (GI), and their compounds differentially modulated P450 1A1 and P450 1B1 gene expression, which are responsible for estrogen detoxification and genotoxicity, respectively. GG and isoliquiritigenin (LigC) increased CYP1A1, whereas GI and its marker compound, licochalcone A (LicA), decreased CYP1A1 and CYP1B1 The objective of this study was to determine the distribution of the bioactive licorice compounds, the metabolism of LicA, and whether GG, GI, and/or pure LicA modulate NAD(P)H quinone oxidoreductase (NQO1) in an ACI rat model. In addition, the effect of licorice extracts and compounds on biomarkers of estrogen chemoprevention (CYP1A1) as well as carcinogenesis (CYP1B1) was studied. LicA was extensively glucuronidated and formed GSH adducts; however, free LicA as well as LigC were bioavailable in target tissues after oral intake of licorice extracts. GG, GI, and LicA caused induction of NQO1 activity in the liver. In mammary tissue, GI increased CYP1A1 and decreased CYP1B1, whereas GG only increased CYP1A1 LigC may have contributed to the upregulation of CYP1A1 after GG and GI administration. In contrast, LicA was responsible for GI-mediated downregulation of CYP1B1 These studies highlight the polypharmacologic nature of botanicals and the importance of standardization of licorice BDS to specific Glycyrrhiza species and to multiple constituents.


Asunto(s)
Suplementos Dietéticos , Estrógenos/metabolismo , Glycyrrhiza/química , Extractos Vegetales/administración & dosificación , Administración Oral , Animales , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Femenino , Sofocos/dietoterapia , Hígado/metabolismo , Hígado/patología , Glándulas Mamarias Animales/metabolismo , Glándulas Mamarias Animales/patología , Modelos Animales , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Extractos Vegetales/farmacocinética , Extractos Vegetales/normas , Ratas , Ratas Endogámicas ACI , Distribución Tisular , Regulación hacia Arriba , Útero/metabolismo , Útero/patología
9.
Chem Res Toxicol ; 30(11): 2084-2092, 2017 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-28985473

RESUMEN

Many women consider botanical dietary supplements (BDSs) as safe alternatives to hormone therapy for menopausal symptoms. However, the effect of BDSs on breast cancer risk is largely unknown. In the estrogen chemical carcinogenesis pathway, P450 1B1 metabolizes estrogens to 4-hydroxylated catechols, which are oxidized to genotoxic quinones that initiate and promote breast cancer. In contrast, P450 1A1 catalyzed 2-hydroxylation represents a detoxification pathway. The current study evaluated the effects of red clover, a popular BDS used for women's health, and its isoflavones, biochanin A (BA), formononetin (FN), genistein (GN), and daidzein (DZ), on estrogen metabolism. The methoxy estrogen metabolites (2-MeOE1, 4-MeOE1) were measured by LC-MS/MS, and CYP1A1 and CYP1B1 gene expression was analyzed by qPCR. Nonmalignant ER-negative breast epithelial cells (MCF-10A) and ER-positive breast cancer cells (MCF-7) were derived from normal breast epithelial tissue and ER+ breast cancer tissue. Red clover extract (RCE, 10 µg/mL) and isoflavones had no effect on estrogen metabolism in MCF-10A cells. However, in MCF-7 cells, RCE treatments downregulated CYP1A1 expression and enhanced genotoxic metabolism (4-MeOE1/CYP1B1 > 2-MeOE1/CYP1A1). Experiments with the isoflavones showed that the AhR agonists (BA, FN) preferentially induced CYP1B1 expression as well as 4-MeOE1. In contrast, the ER agonists (GN, DZ) downregulated CYP1A1 expression likely through an epigenetic mechanism. Finally, the ER antagonist ICI 182,780 potentiated isoflavone-induced XRE-luciferase reporter activity and reversed GN and DZ induced downregulation of CYP1A1 expression. Overall, these studies show that red clover and its isoflavones have differential effects on estrogen metabolism in "normal" vs breast cancer cells. In breast cancer cells, the AhR agonists stimulate genotoxic metabolism, and the ER agonists downregulate the detoxification pathway. These data may suggest that especially breast cancer patients should avoid red clover and isoflavone based BDSs when making choices for menopausal symptom relief.


Asunto(s)
Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/metabolismo , Suplementos Dietéticos/efectos adversos , Estrógenos/metabolismo , Isoflavonas/efectos adversos , Receptores de Hidrocarburo de Aril/metabolismo , Trifolium/metabolismo , Mama/efectos de los fármacos , Mama/metabolismo , Neoplasias de la Mama/genética , Carcinogénesis/metabolismo , Línea Celular , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1/genética , Suplementos Dietéticos/análisis , Femenino , Humanos , Isoflavonas/análisis , Isoflavonas/metabolismo , Células MCF-7
10.
Proc Natl Acad Sci U S A ; 113(42): 11676-11681, 2016 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-27688761

RESUMEN

Camera-guided instruments, such as endoscopes, have become an essential component of contemporary medicine. The 15-20 million endoscopies performed every year in the United States alone demonstrate the tremendous impact of this technology. However, doctors heavily rely on the visual feedback provided by the endoscope camera, which is routinely compromised when body fluids and fogging occlude the lens, requiring lengthy cleaning procedures that include irrigation, tissue rubbing, suction, and even temporary removal of the endoscope for external cleaning. Bronchoscopies are especially affected because they are performed on delicate tissue, in high-humidity environments with exposure to extremely adhesive biological fluids such as mucus and blood. Here, we present a repellent, liquid-infused coating on an endoscope lens capable of preventing vision loss after repeated submersions in blood and mucus. The material properties of the coating, including conformability, mechanical adhesion, transparency, oil type, and biocompatibility, were optimized in comprehensive in vitro and ex vivo studies. Extensive bronchoscopy procedures performed in vivo on porcine lungs showed significantly reduced fouling, resulting in either unnecessary or ∼10-15 times shorter and less intensive lens clearing procedures compared with an untreated endoscope. We believe that the material developed in this study opens up opportunities in the design of next-generation endoscopes that will improve visual field, display unprecedented antibacterial and antifouling properties, reduce the duration of the procedure, and enable visualization of currently unreachable parts of the body, thus offering enormous potential for disease diagnosis and treatment.


Asunto(s)
Materiales Biocompatibles Revestidos , Endoscopía/instrumentación , Endoscopía/normas , Campos Visuales , Broncoscopía/instrumentación , Broncoscopía/métodos , Broncoscopía/normas , Materiales Biocompatibles Revestidos/análisis , Materiales Biocompatibles Revestidos/química , Endoscopios/normas , Endoscopía/métodos , Diseño de Equipo , Humanos
11.
Chem Res Toxicol ; 29(7): 1142-50, 2016 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-27269377

RESUMEN

Humulus lupulus L. (hops) is a popular botanical dietary supplement used by women as a sleep aid and for postmenopausal symptom relief. In addition to its efficacy for menopausal symptoms, hops can also modulate the chemical estrogen carcinogenesis pathway and potentially protect women from breast cancer. In the present study, an enriched hop extract and the key bioactive compounds [6-prenylnarigenin (6-PN), 8-prenylnarigenin (8-PN), isoxanthohumol (IX), and xanthohumol (XH)] were tested for their effects on estrogen metabolism in breast cells (MCF-10A and MCF-7). The methoxyestrones (2-/4-MeOE1) were analyzed as biomarkers for the nontoxic P450 1A1 catalyzed 2-hydroxylation and the genotoxic P450 1B1 catalyzed 4-hydroxylation pathways, respectively. The results indicated that the hop extract and 6-PN preferentially induced the 2-hydroxylation pathway in both cell lines. 8-PN only showed slight up-regulation of metabolism in MCF-7 cells, whereas IX and XH did not have significant effects in either cell line. To further explore the influence of hops and its bioactive marker compounds on P450 1A1/1B1, mRNA expression and ethoxyresorufin O-dealkylase (EROD) activity were measured. The results correlated with the metabolism data and showed that hop extract and 6-PN preferentially enhanced P450 1A1 mRNA expression and increased P450 1A1/1B1 activity. The aryl hydrocarbon receptor (AhR) activation by the isolated compounds was tested using xenobiotic response element (XRE) luciferase construct transfected cells. 6-PN was found to be an AhR agonist that significantly induced XRE activation and inhibited 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced XRE activity. 6-PN mediated induction of EROD activity was also inhibited by the AhR antagonist CH223191. These data show that the hop extract and 6-PN preferentially enhance the nontoxic estrogen 2-hydroxylation pathway through AhR mediated up-regulation of P450 1A1, which further emphasizes the importance of standardization of botanical extracts to multiple chemical markers for both safety and desired bioactivity.


Asunto(s)
Citocromo P-450 CYP1A1/biosíntesis , Estrógenos/metabolismo , Flavonoides/farmacología , Extractos Vegetales/farmacología , Línea Celular Tumoral , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Femenino , Humanos , Humulus/química , Hidroxilación , ARN Mensajero/genética
12.
Sci Rep ; 6: 26109, 2016 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-27189419

RESUMEN

Tissue engineering using whole, intact cell sheets has shown promise in many cell-based therapies. However, current systems for the growth and release of these sheets can be expensive to purchase or difficult to fabricate, hindering their widespread use. Here, we describe a new approach to cell sheet release surfaces based on silicone oil-infused polydimethylsiloxane. By coating the surfaces with a layer of fibronectin (FN), we were able to grow mesenchymal stem cells to densities comparable to those of tissue culture polystyrene controls (TCPS). Simple introduction of oil underneath an edge of the sheet caused it to separate from the substrate. Characterization of sheets post-transfer showed that they retain their FN layer and morphology, remain highly viable, and are able to grow and proliferate normally after transfer. We expect that this method of cell sheet growth and detachment may be useful for low-cost, flexible, and customizable production of cellular layers for tissue engineering.


Asunto(s)
Fibronectinas/metabolismo , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Línea Celular , Células Madre Mesenquimatosas/fisiología , Ratones , Aceites
13.
Nat Commun ; 6: 8649, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26482559

RESUMEN

Formation of unwanted deposits on steels during their interaction with liquids is an inherent problem that often leads to corrosion, biofouling and results in reduction in durability and function. Here we report a new route to form anti-fouling steel surfaces by electrodeposition of nanoporous tungsten oxide (TO) films. TO-modified steels are as mechanically durable as bare steel and highly tolerant to compressive and tensile stresses due to chemical bonding to the substrate and island-like morphology. When inherently superhydrophilic TO coatings are converted to superhydrophobic, they remain non-wetting even after impingement with yttria-stabilized-zirconia particles, or exposure to ultraviolet light and extreme temperatures. Upon lubrication, these surfaces display omniphobicity against highly contaminating media retaining hitherto unseen mechanical durability. To illustrate the applicability of such a durable coating in biofouling conditions, we modified naval construction steels and surgical instruments and demonstrated significantly reduced marine algal film adhesion, Escherichia coli attachment and blood staining.


Asunto(s)
Incrustaciones Biológicas/prevención & control , Galvanoplastia , Óxidos/química , Acero , Tungsteno/química , Interacciones Hidrofóbicas e Hidrofílicas , Nanoporos
14.
Fundam Clin Pharmacol ; 28(5): 551-82, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24612223

RESUMEN

Kinase inhibitors (KIs) represent an important group of anticancer drugs, and many of them are substrates and inhibitors of human cytochrome P450s (CYPs), raising the potential of harmful drug interactions. This study investigated the effect of a library of KIs (n = 91) including 11 FDA-approved KIs on human CYP1A2, 2D6, 2C9, and 3A4 using high-throughput screening kits and the binding modes with CYPs using the Discovery Studio program 3.1. The KIs exhibited differential inhibitory effect on CYP1A2, 2D6, 2C9, and 3A4, while some of them showed activating effect on CYP2C9 and 3A4. For example, SP 600125 was a potent inhibitor for CYP1A2, but enhanced the activity of CYP2C9 fourfolds. Among the 80 KIs that are not used clinically, about 13% showed significant inhibition to CYPs. Nilotinib, sunitinib, and imatinib were found to be potent CYP1A2 inhibitor. Our docking studies have demonstrated the importance of multiple amino acid residues in the active sites of CYP1A2, 2C9, 2D6, and 3A4 in binding with various KIs. Finally, the in vitro data were used to predict potential KI-drug interactions. These findings indicate that many KIs can serve as CYP inhibitors, and further studies are needed to examine the clinical impact.


Asunto(s)
Inhibidores del Citocromo P-450 CYP1A2/metabolismo , Interacciones Farmacológicas , Inhibidores de Proteínas Quinasas/metabolismo , Humanos , Técnicas In Vitro , Funciones de Verosimilitud
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