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1.
Regul Toxicol Pharmacol ; 68(1): 59-69, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24262411

RESUMEN

In order to match the composition of human breast milk more closely, it is now possible to supplement commercial infant formula (IF) with synthesised oligosaccharides that are chemically identical to human milk oligosaccharides. The safety data generated on a new human-identical milk oligosaccharide (HiMO), 2'-O-Fucosyllactose (2'FL), are presented. Standard in vitro genotoxicity tests were performed. To investigate the toxicological profile in a model representative of the intended target population, 2'FL was administered via gavage in a juvenile adapted sub-chronic rat study at dose levels of 0, 2000, 5000 and 6000 mg/kgbw/day. Fructooligosaccharide (FOS), currently acknowledged as safe and approved for use in IF, was used as a reference high-dose control at 6000 mg/kgbw/day. 2'FL was non-mutagenic in the in vitro assays. Oral administration up to 5000 mg/kgbw/day to rats over 90 days was not associated with any adverse effects based on clinical observations, body weight gain, food consumption, ophthalmoscopy, clinical pathology, organ weights and histopathology findings. Based on this 90-day study, a No Observed Adverse Effect Level (NOAEL) of 5000 mg/kgbw/day for both male and female rats was established for 2'FL. These findings support the safety of synthetic 2'FL for possible use in infant food.


Asunto(s)
Trisacáridos/toxicidad , Animales , Animales Recién Nacidos , Línea Celular Tumoral , Femenino , Humanos , Fórmulas Infantiles , Masculino , Ratones , Leche Humana , Pruebas de Mutagenicidad , Ratas , Ratas Wistar , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Pruebas de Toxicidad Subaguda , Pruebas de Toxicidad Subcrónica
2.
Mutat Res ; 692(1-2): 42-8, 2010 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-20709087

RESUMEN

Coffee is among the most frequently consumed beverages worldwide and epidemiological studies indicate that its consumption is inversely related to the incidence of diseases in which reactive oxygen species (ROS) are involved (liver cirrhosis, certain forms of cancer and neurodegenerative disorders). It has been postulated that antioxidant properties of coffee may account for this phenomenon. To find out if consumption of paper filtered coffee which is the most widely consumed form in Central Europe and the US protects humans against oxidative DNA-damage, a controlled intervention trial with a cross-over design was conducted in which the participants (n=38) consumed 800ml coffee or water daily over 5 days. DNA-damage was measured in peripheral lymphocytes in single cell gel electrophoresis assays. The extent of DNA-migration attributable to formation of oxidised purines (formamidopyrimidine glycosylase sensitive sites) was decreased after coffee intake by 12.3% (p=0.006). Biochemical parameters of the redox status (malondialdehyde, 3-nitrotyrosine and the total antioxidant levels in plasma, glutathione concentrations in blood, intracellular ROS levels and the activities of superoxide dismutase and glutathione peroxidase in lymphocytes) were not markedly altered at the end of the trial, also the urinary 8-isoprostaglandine F2α concentrations were not affected. Overall, the results indicate that coffee consumption prevents endogenous formation of oxidative DNA-damage in human, this observation may be causally related to beneficial health effects of coffee seen in earlier studies.


Asunto(s)
Antioxidantes/farmacología , Café , Daño del ADN , Estrés Oxidativo , Adulto , Ensayo Cometa , Femenino , Filtración , Humanos , Masculino
3.
Mol Nutr Food Res ; 54(12): 1722-33, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20589860

RESUMEN

SCOPE: Coffee is among the most frequently consumed beverages. Its consumption is inversely associated to the incidence of diseases related to reactive oxygen species; the phenomenon may be due to its antioxidant properties. Our primary objective was to investigate the impact of consumption of a coffee containing high levels of chlorogenic acids on the oxidation of proteins, DNA and membrane lipids; additionally, other redox biomarkers were monitored in an intervention trial. METHODS AND RESULTS: The treatment group (n=36) consumed instant coffee co-extracted from green and roasted beans, whereas the control consumed water (800 mL/P/day, 5 days). A global statistical analysis of four main biomarkers selected as primary outcomes showed that the overall changes are significant. 8-Isoprostaglandin F2α in urine declined by 15.3%, 3-nitrotyrosine was decreased by 16.1%, DNA migration due to oxidized purines and pyrimidines was (not significantly) reduced in lymphocytes by 12.5 and 14.1%. Other markers such as the total antioxidant capacity were moderately increased; e.g. LDL and malondialdehyde were shifted towards a non-significant reduction. CONCLUSION: The oxidation of DNA, lipids and proteins associated with the incidence of various diseases and the protection against their oxidative damage may be indicative for beneficial health effects of coffee.


Asunto(s)
Ácido Clorogénico/análisis , Café/química , Daño del ADN , Sustancias Macromoleculares/toxicidad , Estrés Oxidativo , Adulto , Antioxidantes/metabolismo , Ensayo Cometa , Dinoprost/análogos & derivados , Dinoprost/orina , Femenino , Humanos , Peroxidación de Lípido , Linfocitos/metabolismo , Masculino , Malondialdehído/análisis , Persona de Mediana Edad , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Tirosina/análogos & derivados , Tirosina/análisis , Adulto Joven
4.
Mol Nutr Food Res ; 54(2): 195-207, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19943261

RESUMEN

In chemical safety assessment, information on adverse effects after chronic exposure to low levels of hazardous compounds is essential for estimating human risks. Results from in vitro studies are often not directly applicable to the in vivo situation, and in vivo animal studies often have to be performed at unrealistic high levels of exposure. Physiologically based biokinetic (PBBK) modeling can be used as a platform for integrating in vitro metabolic data to predict dose- and species-dependent in vivo effects on biokinetics, and can provide a method to obtain a better mechanistic basis for extrapolations of data obtained in experimental animal studies to the human situation. Recently, we have developed PBBK models for the bioactivation of the alkenylbenzene estragole to its DNA binding ultimate carcinogenic metabolite 1'-sulfooxyestragole in both rat and human, as well as rat and human PBBK models for the bioactivation of coumarin to its hepatotoxic o-hydroxyphenylacetaldehyde metabolite. This article presents an overview of the results obtained so far with these in silico methods for PBBK modeling, focusing on the possible implications for risk assessment, and some additional considerations and future perspectives.


Asunto(s)
Anisoles/farmacocinética , Anisoles/toxicidad , Carcinógenos/toxicidad , Biología Computacional/métodos , Cumarinas/farmacocinética , Cumarinas/toxicidad , Sistemas Especialistas , Derivados de Alilbenceno , Animales , Biotransformación , Carcinógenos/metabolismo , Humanos , Modelos Biológicos , Mutágenos/metabolismo , Mutágenos/toxicidad , Plantas Comestibles/química , Plantas Medicinales/química , Medición de Riesgo/métodos , Especificidad de la Especie
5.
J Agric Food Chem ; 50(5): 1200-6, 2002 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-11853504

RESUMEN

Recent model studies on trigonelline decomposition have identified nonvolatile alkylpyridiniums as major reaction products under certain physicochemical conditions. The quaternary base 1-methylpyridinium was isolated from roasted and ground coffee and purified by ion exchange and thin-layer chromatography. The compound was characterized by nuclear magnetic resonance spectroscopy ((1)H, (13)C) and mass spectrometry techniques. A liquid chromatography-electrospray ionization tandem mass spectrometry method was developed to quantify the alkaloid in coffee by isotope dilution mass spectrometry. The formation of alkylpyridiniums is positively correlated to the roasting degree in arabica coffee, and highest levels of 1-methylpyridinium, reaching up to 0.25% on a per weight basis, were found in dark roasted coffee beans. Analyses of coffee extracts also showed the presence of dimethylpyridinium, at concentrations ranging from 5 to 25 mg/kg. This is the first report on the isolation and quantification of alkylpyridiniums in coffee. These compounds, described here in detail for the first time, may have an impact on the flavor/aroma profile of coffee directly (e.g., bitterness), or indirectly as precursors, and potentially open new avenues in the flavor/aroma modulation of coffee.


Asunto(s)
Café/química , Compuestos de Piridinio/análisis , Manipulación de Alimentos/métodos , Hidrógeno , Espectroscopía de Resonancia Magnética , Espectrometría de Masas
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