Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Food Chem Toxicol ; 190: 114787, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38838754

RESUMEN

Lignin-derivable bisguaiacols/bissyringols are viable alternatives to commercial bisphenols; however, many bisguaiacols/bissyringols (e.g., bisguaiacol F [BGF]) have unsubstituted bridging carbons between the aromatic rings, making them more structurally similar to bisphenol F (BPF) than bisphenol A (BPA) - both of which are suspected endocrine disruptors. Herein, we investigated the estrogenic activity (EA) and developmental toxicity of dimethyl-substituted bridging carbon-based lignin-derivable bisphenols (bisguaiacol A [BGA] and bissyringol A [BSA]). Notably, BSA showed undetectable EA at seven test concentrations (from 10-12 M to 10-6 M) in the MCF-7 cell proliferation assay, whereas BPA had detectable EA at five concentrations (from 10-10 M to 10-6 M). In silico results indicated that BSA had the lowest binding affinity with estrogen receptors. Moreover, in vivo chicken embryonic assay results revealed that lignin-derivable monomers had minimal developmental toxicity vs. BPA at environmentally relevant test concentrations (8.7-116 µg/kg). Additionally, all lignin-derivable compounds showed significantly lower expression fold changes (from ∼1.81 to ∼4.41) in chicken fetal liver tests for an estrogen-response gene (apolipoprotein II) in comparison to BPA (fold change of ∼11.51), which was indicative of significantly reduced estrogenic response. Altogether, the methoxy substituents on lignin-derivable bisphenols appeared to be a positive factor in reducing the EA of BPA alternatives.

2.
Food Chem ; 424: 136444, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37257281

RESUMEN

Resveratrol loaded nanoparticles (nano-resveratrol) containing a zein core surrounded by surfactant (Tween-NPs) or carboxymethyl chitosan (CMCS-NPs) shell were fabricated with different particle sizes, surface charges and colloidal stabilities. Changes of physicochemical properties for the two nano-resveratrols, as well as their antioxidant potentials and cytotoxicity were investigated during a static in vitro gastrointestinal tract (GIT) digestion. Results showed that the Tween-NPs had a much higher bioaccessibility (84.1 ± 19.2%) than that of CMCS-NPs (36.6 ± 4.2%) after the GIT digestion, which was expected due to the steric barrier of the CMCS coating. Both nano-resveratrols could sustained their antioxidant activities after digestion. However, the Tween-NPs had a significantly higher cytotoxicity against MCF-7 cells than CMCS-NPs and free resveratrol, while a reduction in cytotoxicity of Tween-NPs was observed after the digestion. The bioactivities results were well correlated with the physicochemical properties and dissolution of resveratrol under environmental stress.


Asunto(s)
Quitosano , Nanopartículas , Resveratrol/farmacología , Antioxidantes/farmacología , Polisorbatos , Nanopartículas/química , Biopolímeros , Digestión , Tamaño de la Partícula , Quitosano/farmacología , Quitosano/química
3.
Bioresour Technol ; 371: 128579, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36610484

RESUMEN

Via combination catalysis with deep eutectic solvent lactic acid:betaine (chemocatalyst) and HMFOMUT cell (biocatalyst: E. coli HMFOMUT whole-cell), one-pot manufacture of 2,5-furandimethanol from waste bioresource was constructed in a chemoenzymatic approach. With bread waste (50 g/L) as substrate, the 5-hydroxymethylfuran yield reached 44.2 Cmol% (based on bread waste) by lactic acid:betaine (15 wt%) at 180 °C for 15 min. With glucose as co-substrate, HMFOMUT could transform 5-hydroxymethylfurfural (150 mM) to 2,5-furandimethanol (84.5 % yield) after 1 day at 37 °C and pH 7.0. In lactic acid:betaine-H2O, HMFOMUT effectively converted bread-derived 5-hydroxymethylfurfural into 2,5-furandimethanol in a productivity of 700 kg 2,5-furandimethanol per kg 5-hydroxymethylfurfural (230 kg 2,5-furandimethanol per kg bread). In an eco-friendly lactic acid:betaine system, an effective one-pot chemoenzymatic strategy was firstly developed to convert bread waste into 2,5-furandimethanol, which would reduce the operation cost and has potential application value for valorizing waste food bioresource into value-added furan.


Asunto(s)
Pan , Escherichia coli , Betaína , Ácido Láctico
4.
Theranostics ; 12(18): 7681-7698, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36451864

RESUMEN

Rationale: Increased lipid droplet (LD) formation has been linked to tumor metastasis, stemness, and chemoresistance in various types of cancer. Here, we revealed that LD formation is critical for the adaptation to sorafenib in hepatocellular carcinoma (HCC) cells. We aim to investigate the LD function and its regulatory mechanisms in HCC. Methods: The key proteins responsible for LD formation were screened by both metabolomics and proteomics in sorafenib-resistant HCC cells and further validated by immunoblotting and immunofluorescence staining. Biological function of AKR1C3 was evaluated by CRISPR/Cas9-based gene editing. Isotopic tracing analysis with deuterium3-labeled palmitate or carbon13-labeled glucose was conducted to investigate fatty acid (FA) and glucose carbon flux. Seahorse analysis was performed to assess the glycolytic flux and mitochondrial function. Selective AKR1C3 inhibitors were used to evaluate the effect of AKR1C3 inhibition on HCC tumor growth and induction of autophagy. Results: We found that long-term sorafenib treatment impairs fatty acid oxidation (FAO), leading to LD accumulation in HCC cells. Using multi-omics analysis in cultured HCC cells, we identified that aldo-keto reductase AKR1C3 is responsible for LD accumulation in HCC. Genetic loss of AKR1C3 fully depletes LD contents, navigating FA flux to phospholipids, sphingolipids, and mitochondria. Furthermore, we found that AKR1C3-dependent LD accumulation is required for mitigating sorafenib-induced mitochondrial lipotoxicity and dysfunction. Pharmacologic inhibition of AKR1C3 activity instantly induces autophagy-dependent LD catabolism, resulting in mitochondrial fission and apoptosis in sorafenib-resistant HCC clones. Notably, manipulation of AKR1C3 expression is sufficient to drive the metabolic switch between FAO and glycolysis. Conclusions: Our findings revealed that AKR1C3-dependent LD formation is critical for the adaptation to sorafenib in HCC through regulating lipid and energy homeostasis. AKR1C3-dependent LD accumulation protects HCC cells from sorafenib-induced mitochondrial lipotoxicity by regulating lipophagy. Targeting AKR1C3 might be a promising therapeutic strategy for HCC tumors.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Sorafenib/farmacología , Gotas Lipídicas , Neoplasias Hepáticas/tratamiento farmacológico , Ácidos Grasos , Glucosa , Miembro C3 de la Familia 1 de las Aldo-Ceto Reductasas
5.
Adv Sci (Weinh) ; : e2202642, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36382559

RESUMEN

Lacking a clear understanding of the molecular mechanism determining cancer cell sensitivity to oxidative phosphorylation (OXPHOS) inhibition limits the development of OXPHOS-targeting cancer treatment. Here, cancer cell lines sensitive or resistant to OXPHOS inhibition are identified by screening. OXPHOS inhibition-sensitive cancer cells possess increased OXPHOS activity and silenced nicotinamide N-methyltransferase (NNMT) expression. NNMT expression negatively correlates with OXPHOS inhibition sensitivity and functionally downregulates the intracellular levels of S-adenosyl methionine (SAM). Expression of DNA methyltransferase 1 (DNMT1), a SAM consumer, positively correlates with OXPHOS inhibition sensitivity. NNMT overexpression and DNMT1 inhibition render OXPHOS inhibition-sensitive cancer cells resistant. Importantly, treatments of OXPHOS inhibitors (Gboxin and Berberine) hamper the growth of mouse tumor xenografts by OXPHOS inhibition sensitive but not resistant cancer cells. What's more, the retrospective study of 62 tumor samples from a clinical trial demonstrates that administration of Berberine reduces the tumor recurrence rate of NNMTlow /DNMT1high but not NNMThigh /DNMT1low colorectal adenomas (CRAs). These results thus reveal a critical role of the NNMT-DNMT1 axis in determining cancer cell reliance on mitochondrial OXPHOS and suggest that NNMT and DNMT1 are faithful biomarkers for OXPHOS-targeting cancer therapies.

6.
ACS Omega ; 7(6): 4757-4768, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35187296

RESUMEN

Flavonoids are bioactive phenolic compounds widely present in plant food and used in various nutraceutical, pharmaceutical, and cosmetic products. However, recent studies showed rising concerns of endocrine disruptions and developmental toxicities for many flavonoids. To understand the impacts of flavonoid structure on toxicity, we used a new multitiered platform to investigate the toxicities of four common flavonoids, luteolin, apigenin, quercetin, and genistein, from flavone, flavonol, and isoflavone. Weak estrogenic activity was detected for four flavonoids (genistein, apigenin, quercetin, and luteolin) at 10-12 to 10-7 M by the MCF-7 cell proliferation assay, which agreed with the molecular docking results. Consistent with the simulation results of Toxicity Estimation Software Tool, genistein and luteolin showed high developmental toxicity in the chicken embryonic assay (45-477 µg/kg) with mortality rate up to 50%. Luteolin, quercetin, and apigenin showed signs of mutagenicity at 5 × 10-3 pmol/plate. The findings showed nonmonotonic dose responses for the chemicals.

7.
Carcinogenesis ; 42(5): 753-761, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-33677528

RESUMEN

Sorafenib is commonly used to treat advanced human hepatocellular carcinoma (HCC). However, clinical efficacy has been limited by drug resistance. In this study, we used label-free quantitative proteomic analysis to systematically investigate the underlying mechanisms of sorafenib resistance in HCC cells. A total of 1709 proteins were confidently quantified. Among them, 89 were differentially expressed and highly enriched in the processes of cell-cell adhesion, negative regulation of apoptosis, response to drug and metabolic processes involving in sorafenib resistance. Notably, folate receptor α (FOLR1) was found to be significantly upregulated in resistant HCC cells. In addition, in vitro studies showed that overexpression of FOLR1 decreased the sensitivity of HCC cells to sorafenib, whereas siRNA-directed knockdown of FOLR1 increased the sensitivity of HCC cells to sorafenib. Immunoprecipitation-mass spectrometry analysis suggested a strong link between FOLR1 and autophagy-related proteins. Further biological experiments found that FOLR1-related sorafenib resistance was accompanied by the activation of autophagy, whereas inhibition of autophagy significantly reduced FOLR1-induced cell resistance. These results suggest the driving role of FOLR1 in HCC resistance to sorafenib, which may be exerted through FOLR1-induced autophagy. Therefore, this study may provide new insights into understanding the mechanism of sorafenib resistance.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Receptor 1 de Folato/genética , Neoplasias Hepáticas/tratamiento farmacológico , Proteómica , Apoptosis/efectos de los fármacos , Autofagia/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Sorafenib/efectos adversos , Sorafenib/farmacología
8.
Food Chem Toxicol ; 150: 112038, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33571611

RESUMEN

Thymol and carvacrol are phenolic isomers with the potential developmental toxicity and endocrine disruptions (ED) at low concentrations. However, few reports estimated their toxicity and ED below 10-6 M (150 µg/L) (MW of thymol and carvacrol: 150 g/mol). In this study, both chemicals were determined for the developmental toxicity and potential ED at 500 µg/kg and 50 µg/kg using the chicken embryonic assay, potential estrogenic activity (EA) at 10-12 to 10-7 M (1.5 × 10-4 to 15 µg/L) by the MCF-7 cell proliferation assay, mutagenicity at 10-12 to 10-6 M (1.5 × 10-4 to 150 µg/L) by the Ames test, and an in silico method for ED. Carvacrol showed mutagenic risks at 10-7, 10-8, and 10-11 M (15, 1.5, and 0.0015 µg/L) while thymol at 10-6 and 10-8 M (150 and 1.5 µg/L). Carvacrol negatively impacted embryonic growth at 50 µg/kg, with weak EA at 10-8 M (1.5 µg/L). Carvacrol but not thymol had weak EA at 10-12 M (1.5 × 10-4 µg/L). Molecular docking to 14 types of hormone-related receptors revealed that carvacrol had higher binding affinities to two estrogen receptors and the mineralocorticoid receptor than those to thymol. Carvacrol and thymol varied in toxicities due to a different location of one phenolic hydroxyl group.


Asunto(s)
Cimenos/toxicidad , Estrógenos/toxicidad , Timol/toxicidad , Animales , Embrión de Pollo , Cimenos/administración & dosificación , Cimenos/química , Estradiol/química , Estradiol/farmacología , Humanos , Células MCF-7 , Simulación del Acoplamiento Molecular , Estructura Molecular , Mutagénesis , Unión Proteica , Receptores de Estrógenos , Timol/administración & dosificación , Timol/química
9.
Food Chem ; 338: 127656, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32798821

RESUMEN

Bisguaiacols are promising lignin-derivable alternatives to bisphenol A (BPA), but limited bioassay data are available on their estrogenic activity (EA). Herein, we investigated the estrogen receptor alpha (ERα)-mediated EA of six newly synthesized bisguaiacols, which differed in the number and location of methoxy substituents, through in vitro assays: MCF-7 cell proliferation and VM7Luc4E2 transactivation. The six bisguaiacols had undetectable EA at concentrations less than 10-7 M, most importantly, with significantly lower EA than BPA over an environmentally relevant range of 10-10-10-7 M. Adding a single methoxy group led to significant reduction in EA in all cases, relative to BPA and one petroleum-derived BPA analogue (bisphenol F, BPF), and the incorporation of more methoxy groups had subtler, but pronounced, impacts on either ERα binding or MCF-7 cell proliferation. In short, the six lignin-inspired bisguaiacols presented herein are viewed as promising sustainable alternatives to BPA and BPF.


Asunto(s)
Compuestos de Bencidrilo/química , Estrógenos/química , Lignina/química , Fenoles/química , Compuestos de Bencidrilo/farmacología , Proliferación Celular/efectos de los fármacos , Estrógenos/metabolismo , Estrógenos/farmacología , Humanos , Células MCF-7 , Oxidación-Reducción , Fenoles/farmacología , Unión Proteica , Relación Estructura-Actividad , Activación Transcripcional/efectos de los fármacos
10.
J Exp Clin Cancer Res ; 38(1): 83, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30770740

RESUMEN

BACKGROUND: The bromodomain and extra-terminal domain (BET) inhibitor is a type of anti-tumor agent, currently being evaluated in phase I and II clinical trials for cancer therapy. It can decrease MYC expression levels and cause effective anti-tumor effects in diverse human cancers. However, its cytotoxic effect and related mechanisms of drug resistance are poorly understood in hepatocellular carcinomas (HCC). Here, we investigated the anti-tumor effects of BET inhibitor on HCC and the molecular mechanisms involved in its associated drug resistance. METHODS: We assessed the cytotoxicity of BET inhibitor on HCC cells compared with sorafenib by cell viability assay, metastasis assay and reproduced the anti-tumor effect in xenograft mouse model. In addition, the molecular mechanisms involved in drug resistance on JQ1-resistant HCC cells were revealed by western blotting, qRT-PCR, whole exome-sequencing and gene-editing technology. Finally, with specific inhibition of EGFR or ERK activity by interference RNAs or inhibitors, the efficacy of the synergistic treatment was investigated using cell viability assay, colony formation, apoptosis and xenograft mouse model. RESULTS: We found that JQ1, a commonly used BET bromo-domain inhibitor, offered a better anti-tumor response than sorafenib in MYC-positive HCC cells by inducing apoptosis in vitro and in vivo. Unlike sorafenib, JQ1 treatment significantly impaired mitochondrial respiration and glycolysis in HCC cells. Importantly, we revealed that MAPK activation by a previously undescribed activating mutation of EGFR-I645L, was critical for JQ1 sensitivity through stabilizing oncogenic MYC protein in JQ1-resistant HCC cells. Inhibition of either EGFR or ERK activity overcame the JQ1 resistance and significantly decreased MYC protein level in vitro and in vivo. CONCLUSION: Since MYC amplification is frequently identified in HCC, co-occurring with EGFR amplification, our findings suggest that targeting EGFR signaling might be essential for JQ1 therapy in advanced HCC.


Asunto(s)
Carcinoma Hepatocelular/patología , Resistencia a Antineoplásicos/fisiología , Neoplasias Hepáticas/patología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Animales , Antineoplásicos/farmacología , Azepinas/farmacología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Ratones , Proteínas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-myc/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Sorafenib/farmacología , Triazoles/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
11.
J Agric Food Chem ; 66(44): 11775-11783, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30284437

RESUMEN

Alternatives to bisphenol A (BPA), such as lignin-inspired bisguaiacol F (BGF), are of interest for food contact materials due to increasing evidence of estrogenic activity (EA) and exposure-correlated harmful effects of BPA and its analogues. BGF has similar thermal and mechanical properties to BPA, but contains additional methoxy substituents that may significantly reduce its endocrine disruption potential. In this study, the EA of four BGF samples with different regioisomer ratios was quantified relative to 17ß-estradiol at ten concentrations by using two in vitro assays: MCF-7 cell proliferation and VM7Luc4E2 transactivation (TA). The results suggest BGF mixtures with higher molar ratios of p, p'-BGF and o, p'-BGF regioisomers exhibited lower EA than BPA, while BGF samples containing higher molar ratios of m, p'-BGF had no detectable EA over a wide range of test concentrations. These findings suggest the potential of BGF as a viable alternative to BPA for use in more environmentally friendly materials.


Asunto(s)
Compuestos de Bencidrilo/química , Disruptores Endocrinos/química , Estrógenos/análogos & derivados , Fenoles/química , Compuestos de Bencidrilo/farmacología , Bioensayo , Línea Celular , Proliferación Celular/efectos de los fármacos , Disruptores Endocrinos/farmacología , Estrógenos/farmacología , Humanos , Estructura Molecular , Fenoles/farmacología
12.
Appl Biochem Biotechnol ; 184(1): 350-365, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28688047

RESUMEN

Lignin accounts for 15-35% of dry biomass materials. Therefore, developing value-added co-products from lignin residues is increasingly important to improve the economic viability of biofuel production from biomass resources. The main objective of this work was to study the lignin extracts from corn stover residue obtained from a new and improved process for bioethanol production. Extraction conditions that favored high lignin yield were optimized, and antioxidant and antimicrobial activities of the resulting lignin were investigated. Potential estrogenic toxicity of lignin extracts was also evaluated. The corn stover was pretreated by low-moisture anhydrous ammonia (LMAA) and then subjected to enzymatic hydrolysis using cellulase and hemicellulase. The residues were then added with sodium hydroxide and extracted for different temperatures and times for enhancing lignin yield and the bioactivities. The optimal extraction conditions using 4% (w/v) sodium hydroxide were determined to be 50 °C, 120 min, and 1:8 (w:v), the ratio between corn stover solids and extracting liquid. Under the optimal condition, 33.92 g of lignin yield per 100 g of corn stover residue was obtained. Furthermore, the extracts produced using these conditions showed the highest antioxidant activity by the hydrophilic oxygen radical absorbance capacity (ORAC) assay. The extracts also displayed significant antimicrobial activities against Listeria innocua. Minimal estrogenic impacts were observed for all lignin extracts when tested using the MCF-7 cell proliferation assay. Thus, the lignin extracts could be used for antioxidant and antimicrobial applications, and improve the value of the co-products from the biomass-based biorefinery.


Asunto(s)
Amoníaco/química , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Celulasa/química , Glicósido Hidrolasas/química , Zea mays/química , Animales , Línea Celular , Hidrólisis , Ratones
13.
Mol Ther ; 25(6): 1408-1419, 2017 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-28528817

RESUMEN

It has long been believed that most female mammalian species lose the ability to generate oocytes in postnatal ovaries. Recent evidence has demonstrated the isolation and culture of female germline stem cells (FGSCs) from adult mice and humans. However, the process and mechanisms of FGSC differentiation in vivo following transplantation have not yet been studied. Here, we isolated and characterized FGSCs from a single EGFP-transgenic mouse, and traced the development and behavior of transplanted FGSCs (F-TFs) in vivo. Comparisons of folliculogenesis between recipients with FGSC transplantation and wild-type (WT) mice were performed by single follicle RNA-sequencing (RNA-seq). Results showed that FGSCs exhibited a homing ability and began to differentiate into early-stage oocytes only when they reached the edge of the ovarian cortex. The F-TFs restored function of premature ovarian failure (gdf9iCre; PtenloxP/loxP genotype) and generated offspring. Furthermore, results demonstrated that the developmental mechanisms of follicles derived from F-TFs were similar to that of WT follicles. Weighted gene co-expression network analysis identified two potential sub-networks and core genes that played a critical role in follicular development. These findings provide a theoretical basis and lay a technology platform for specific or personalized medical treatment of ovarian failure or other ovarian diseases.


Asunto(s)
Rastreo Celular/métodos , Células Germinativas/citología , Células Germinativas/metabolismo , Trasplante de Células Madre , Células Madre/citología , Células Madre/metabolismo , Animales , Biomarcadores , Femenino , Técnica del Anticuerpo Fluorescente , Expresión Génica , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Genes Reporteros , Ratones , Ratones Transgénicos , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Ovario/citología , Ovario/fisiología
14.
Food Microbiol ; 57: 135-43, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27052712

RESUMEN

Raspberries have served as vehicles for transmission of foodborne pathogens through fecal-oral route and have resulted in 11 outbreaks in the United States from 1983 through 2013. However, because of its dedicated structures and perishability, water based sanitizer washing cannot be used for raspberry decontamination. As a non-thermal technique, pulsed light (PL) may have the potential to maintain both safety and quality of fresh raspberries. The first objective of our study was to investigate Salmonella and Escherichia coli O157:H7 inactivation efficacy of pulsed light (PL) on fresh raspberries during 10 days storage at 4 °C. The qualities of raspberries after PL treatment, including color, texture, total phenolic content (TPC), total anthocyanin content (TAC), total bacteria count (TBC) as well as total yeast and mold count (TYMC), have also been evaluated during the 10 days storage. Compared with the untreated control, all the PL treatments (5 s, 15 s and 30 s) maintained lower pathogen survival population during 10 days refrigerated storage. At day 10, all PL treated raspberries maintained significantly lower TBC and TYMC than the control. Although PL treatment for 30 s (with fluence of 28.2 J/cm(2)) reduced most Salmonella and E. coli O157:H7 right after treatment, by 4.5 and 3.9 log 10 CFU/g respectively, it failed to maintain its advantage during storage. In addition, color and texture of these raspberries changed negatively after 10 days storage. PL 30 s provided the lowest TBC and TYMC at day 0, but failed to maintain its advantage during storage. To consider both safety and quality of fresh raspberries as well as the treatment feasibility, 5 s PL treatment with fluence of 5.0 J/cm(2) was recommended for decontamination. The second objective was to study attachment of bacteria as well as decontamination effect of PL on raspberries. Under the scanning electron microscopy (SEM), PL showed severe damage to the cell membrane on smooth surface. Surface structure of raspberries affected the attachment of bacterial cells and the surface roughness provided protection for pathogenic bacteria. Our research demonstrated for the first time that successful PL processing of raspberries should be evaluated for its impacts on both produce safety and quality during the storage. PL with fluence of 5.0 J/cm(2) maintained both safety and quality of fresh raspberries during the refrigerated storage.


Asunto(s)
Adhesión Bacteriana/efectos de la radiación , Descontaminación/métodos , Escherichia coli O157/efectos de la radiación , Conservación de Alimentos/métodos , Frutas/microbiología , Rubus/microbiología , Salmonella/efectos de la radiación , Descontaminación/instrumentación , Escherichia coli O157/crecimiento & desarrollo , Escherichia coli O157/fisiología , Contaminación de Alimentos/prevención & control , Conservación de Alimentos/instrumentación , Luz , Salmonella/crecimiento & desarrollo , Salmonella/fisiología
15.
Mol Hum Reprod ; 20(3): 271-81, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24258451

RESUMEN

Germline stem cell lines possess the abilities of self-renewal and differentiation, and have been established from both mouse and human ovaries. Here, we established a new female germline stem cell (FGSC) line from post-natal rats by immunomagnetic sorting for Fragilis, which showed a normal karyotype, high telomerase activity, and a consistent gene expression pattern of primordial germ cells after 1 year of culture. Using an in vitro differentiation system, the FGSC line could differentiate into oocytes. After liposome-based transfection with green fluorescent protein (GFP) or fat-1 vectors, the FGSCs were transplanted into the ovaries of infertile rats. The transplanted FGSCs underwent oogenesis, and the rats produced offspring carrying the GFP or fat-1 transgene after mating with wild-type male rats. The efficiency of gene transfer was 27.86-28.00%, and 2 months was needed to produce transgenic rats. These findings have implications in biomedical research and potential applications in biotechnology.


Asunto(s)
Efecto Fundador , Oocitos/citología , Ovario/citología , Ratas Transgénicas/genética , Células Madre/citología , Animales , Animales Recién Nacidos , Diferenciación Celular , Femenino , Expresión Génica , Genes Reporteros , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Cariotipificación , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Oocitos/metabolismo , Oogénesis/genética , Ovario/metabolismo , Ratas , Trasplante de Células Madre , Células Madre/metabolismo , Telomerasa/genética , Telomerasa/metabolismo
16.
Food Chem ; 141(3): 1923-33, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23870911

RESUMEN

The reduced incidence of prostate cancer (PCa) in Asia countries has been attributed to high soy diets, and major soy isoflavones, in particular daidzein and genistein, are thought to be the source of the beneficial and anti-cancer effects of soy foods. However, attention has been drawn to the safety of using high levels of soy isoflavones in humans, which is especially the concern for consumers taking regular soy isoflavone dietary supplements. The main objective of this study is thus to identify a soy isoflavone combination with lower levels of daidzein and genistein to be a more efficacious and safer chemo-preventive agent for PCa. The anticancer effects of daidzein and genistein, and their combinations on early-stage androgen-dependent PCa cells (LNCaP) and bone metastatic LNCaP-derivative PCa cells (C4-2B) were compared. Cells were treated with varying concentrations of daidzein, genistein (25-200 µM) or their combinations (25 or 50 µM) and cell proliferation, apoptosis, cell cycles and cellular uptakes of the isoflavones were measured after 48 h. Daidzein and genistein showed a synergistic effect on inhibiting cell proliferation and inducing apoptosis of both PCa cells. Twenty-five µM daidzein/50 µM genistein and 50 µM daidzein/50 µM genistein significantly increased the apoptotic effects on C4-2B cells although they did not show any effect when used individually. Except 50 µM daidzein/50 µM genistein, all other combinations had no impacts on cell cycles. For treatment with soy isoflavone combination, genistein was always better taken up than daidzein by both LNCaP and C4-2B cells.


Asunto(s)
Genisteína/farmacología , Glycine max/química , Isoflavonas/farmacología , Extractos Vegetales/farmacología , Neoplasias de la Próstata/prevención & control , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sinergismo Farmacológico , Humanos , Masculino , Neoplasias de la Próstata/fisiopatología
17.
Antiviral Res ; 98(1): 76-84, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23403209

RESUMEN

In this study, RNA polymerase I expressed replicons containing EGFP and luciferase reporter genes controlled by influenza vRNA or cRNA promoters were compared side-by-side in the ability to detect influenza RNA-dependent RNA polymerase activity as an indicator of influenza replication. Results showed the vRNA based Luc reporter was more sensitive to early detection of influenza virus at 6h post infection (p<0.05), and at 10-fold lower titer (MOI=0.001). Lower sensitivity of cRNA based Luc reporter constructs was due to its background expression, 2-fold lower expression, and around 4h delay in expression of luciferase. Despite these differences, both cRNA- and vRNA-based reporters demonstrated strong correlation between MOI and luciferase signal, and can be used for effective and early detection of influenza infection in vitro. Further, we demonstrated that these reporters can be used successfully to study the kinetics of antiviral drugs including siRNA. Our results also suggest that progeny vRNAs might participate not only in secondary transcription but also in secondary replication. The developed cRNA and vRNA reporters may help with further elucidation of the replication model of influenza A virus.


Asunto(s)
Virus de la Influenza A/genética , Gripe Humana/virología , Regiones Promotoras Genéticas , ARN Complementario/genética , ARN Viral/genética , Replicación Viral , Línea Celular Tumoral , Genes Reporteros , Humanos , Virus de la Influenza A/enzimología , Virus de la Influenza A/fisiología , ARN Polimerasa I/genética , ARN Polimerasa I/metabolismo , ARN Complementario/metabolismo , ARN Viral/metabolismo , Transcripción Genética , Proteínas Virales/genética , Proteínas Virales/metabolismo
18.
Neural Regen Res ; 8(3): 197-207, 2013 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-25206589

RESUMEN

Buyang Huanwu Decoction fraction extracted from Buyang Huanwu Decoction contains saponins of Astragalus, total paeony glycoside and safflower flavones. The aim of this study was to demonstrate the neuroprotective effect and mechanism of Buyang Huanwu Decoction fraction on ischemic injury both in vivo and in vitro. In vivo experiments showed that 50-200 mg/kg Buyang Huanwu Decoction fraction reduced infarct volume and pathological injury in ischemia/reperfusion rats, markedly inhibited expression of nuclear factor-κB and tumor necrosis factor-α and promoted nestin protein expression in brain tissue. Buyang Huanwu Decoction fraction (200 mg/kg) exhibited significant effects, which were similar to those of 100 mg/kg Ginkgo biloba extract. In vitro experimental results demonstrated that 10-100 mg/L Buyang Huanwu Decoction fraction significantly improved cell viability, decreased the release of lactate dehydrogenase and malondialdehyde levels, and inhibited the rate of apoptosis in HT22 cells following oxygen-glucose deprivation. Buyang Huanwu Decoction fraction (100 mg/L) exhibited significant effects, which were similar to those of 100 mg/L Ginkgo biloba extract. These findings suggest that Buyang Huanwu Decoction fraction may represent a novel, protective strategy against cerebral ischemia/reperfusion injury in rats and oxygen-glucose deprivation-induced damage in HT22 cells in vitro by attenuating the inflammatory response and cellular apoptosis.

19.
Food Chem ; 135(3): 1643-52, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22953905

RESUMEN

Previous laboratory and animal studies reported that soy isoflavones were major bioactive compounds in soy to exert chemoprotection of prostate cancer. However, these studies cannot reflect the realistic effects that soy may induce through diets, and little is known about the bioavailability of isoflavones from whole soy food and their bioactivities after cooking and digestion. In this study, cooking and in vitro digestion were used to prepare soy extracts and the effects of cooking and digestion on the isoflavone contents and bioactivities of the whole soy extracts were examined. The cooking procedure generally increased the amount of daidzin, genistin and daidzein, but decreased that of genistein. Digestion process significantly lowered contents of daidzin and genistin in 60min cooked sample, while increased the contents of daidzin and daidzein and decreased the content of genistein in the uncooked sample. Antioxidant activities of soy extracts increased after cooking and in vitro digestion, while no consistent increase of the four soy isoflavones was determined. The apoptotic effects of soy extracts on both LNCaP and C4-2B cells were generally in a dose-dependent manner. Compared to purified single isoflavones, cooked and digested soy were more effective on induction of prostate cancer cell apoptosis, which indicated synergistic interactions between various bioactive compounds in the whole soy.


Asunto(s)
Apoptosis/efectos de los fármacos , Glycine max/química , Isoflavonas/farmacología , Extractos Vegetales/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Culinaria , Digestión , Humanos , Isoflavonas/química , Isoflavonas/metabolismo , Masculino , Modelos Biológicos , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/fisiopatología , Glycine max/metabolismo
20.
J Food Prot ; 73(12): 2270-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21219747

RESUMEN

In recent years, multistate outbreaks of Salmonella enterica serovars were traced to tomatoes and resulted in serious economic loss for the tomato industry and decreased consumer confidence in the safety of tomato produce. Purified compounds derived from essential oils such as thymol and carvacrol had wide inhibitory effects against foodborne pathogens including Salmonella. The objective of this study was to determine the antimicrobial activities of thymol, carvacrol, and thyme oil against Salmonella on grape tomatoes. Surface-inoculated grape tomatoes were washed with 4% ethanol, 200 ppm of chlorine, or one of six washing solutions (thymol [0.2 and 0.4 mg/ml], thyme oil [1 and 2 mg/ml], and carvacrol [0.2 and 0.4 mg/ml]) for 5 or 10 min. There was no significant difference in the reduction of S. enterica serovars when different washing times were used (P > 0.05). Thymol (especially at the concentration of 0.4 mg/ml) was the most effective (P < 0.05) among the three natural antimicrobial agents, which achieved >4.1-log reductions of S. enterica serovars Typhimurium, Kentucky, Senftenberg, and Enteritidis on grape tomatoes after a 5-min washing and >4.3-log reductions after a 10-min washing. A >4.6-log reduction in the S. enterica populations in comparison to control was observed with the use of thymol solutions. The uses of these antimicrobial agents achieved significant log reductions of Salmonella on inoculated grape tomatoes and decreased dramatically the risk of potential transmission of pathogens from tomatoes to washing solutions. None of these antimicrobial agents decreased the total phenolic and ascorbic acid content, nor did any of them change the color and pH values or affect the taste, aroma, or visual quality of grape tomatoes. Therefore, 0.4 mg/ml thymol has great potential to be an alternative to chlorine-based washing solution for fresh produce.


Asunto(s)
Conservación de Alimentos/métodos , Conservantes de Alimentos/farmacología , Salmonella enterica/efectos de los fármacos , Solanum lycopersicum/microbiología , Cloro/farmacología , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Cimenos , Relación Dosis-Respuesta a Droga , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Humanos , Monoterpenos/farmacología , Aceites de Plantas/farmacología , Salmonella enterica/crecimiento & desarrollo , Timol/farmacología , Thymus (Planta)/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA