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1.
FASEB J ; 36(11): e22534, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36183361

RESUMEN

The solute carrier 26 family member A9 (SLC26A9) is an epithelial anion transporter that is assumed to contribute to airway chloride secretion and surface hydration. Whether SLC26A9 or CFTR is responsible for airway Cl- transport under basal conditions is still unclear, due to the lack of a specific inhibitor for SLC26A9. In the present study, we report a novel potent and specific inhibitor for SLC26A9, identified by screening of a drug-like molecule library and subsequent chemical modifications. The most potent compound S9-A13 inhibited SLC26A9 with an IC50 of 90.9 ± 13.4 nM. S9-A13 did not inhibit other members of the SLC26 family and had no effects on Cl- channels such as CFTR, TMEM16A, or VRAC. S9-A13 inhibited SLC26A9 Cl- currents in cells that lack expression of CFTR. It also inhibited proton secretion by HGT-1 human gastric cells. In contrast, S9-A13 had minimal effects on ion transport in human airway epithelia and mouse trachea, despite clear expression of SLC26A9 in the apical membrane of ciliated cells. In both tissues, basal and stimulated Cl- secretion was due to CFTR, while acidification of airway surface liquid by S9-A13 suggests a role of SLC26A9 for airway bicarbonate secretion.


Asunto(s)
Cloruros , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Animales , Antiportadores/metabolismo , Bicarbonatos/metabolismo , Cloruros/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Células Epiteliales/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Ratones , Protones , Transportadores de Sulfato/genética , Transportadores de Sulfato/metabolismo
2.
Int J Mol Sci ; 22(11)2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-34070942

RESUMEN

Among mammals, serotonin is predominantly found in the gastrointestinal tract, where it has been shown to participate in pathway-regulating satiation. For the stomach, vascular serotonin release induced by gastric distension is thought to chiefly contribute to satiation after food intake. However, little information is available on the capability of gastric cells to synthesize, release and respond to serotonin by functional changes of mechanisms regulating gastric acid secretion. We investigated whether human gastric cells are capable of serotonin synthesis and release. First, HGT-1 cells, derived from a human adenocarcinoma of the stomach, and human stomach specimens were immunostained positive for serotonin. In HGT-1 cells, incubation with the tryptophan hydroxylase inhibitor p-chlorophenylalanine reduced the mean serotonin-induced fluorescence signal intensity by 27%. Serotonin release of 147 ± 18%, compared to control HGT-1 cells (set to 100%) was demonstrated after treatment with 30 mM of the satiating amino acid L-Arg. Granisetron, a 5-HT3 receptor antagonist, reduced this L-Arg-induced serotonin release, as well as L-Arg-induced proton secretion. Similarly to the in vitro experiment, human antrum samples released serotonin upon incubation with 10 mM L-Arg. Overall, our data suggest that human parietal cells in culture, as well as from the gastric antrum, synthesize serotonin and release it after treatment with L-Arg via an HTR3-related mechanism. Moreover, we suggest not only gastric distension but also gastric acid secretion to result in peripheral serotonin release.


Asunto(s)
Arginina/farmacología , Ácido Gástrico/metabolismo , Células Parietales Gástricas/efectos de los fármacos , Protones , Serotonina/biosíntesis , Línea Celular Tumoral , Fenclonina/farmacología , Expresión Génica , Granisetrón/farmacología , Humanos , Concentración de Iones de Hidrógeno , Células Parietales Gástricas/citología , Células Parietales Gástricas/metabolismo , Inhibidores de Proteasas/farmacología , Receptores de Serotonina 5-HT3/genética , Receptores de Serotonina 5-HT3/metabolismo , Antagonistas de la Serotonina/farmacología , Estómago/citología , Estómago/efectos de los fármacos , Técnicas de Cultivo de Tejidos , Triptófano Hidroxilasa/antagonistas & inhibidores , Triptófano Hidroxilasa/genética , Triptófano Hidroxilasa/metabolismo
3.
Proc Natl Acad Sci U S A ; 114(30): E6260-E6269, 2017 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-28696284

RESUMEN

Caffeine, generally known as a stimulant of gastric acid secretion (GAS), is a bitter-tasting compound that activates several taste type 2 bitter receptors (TAS2Rs). TAS2Rs are expressed in the mouth and in several extraoral sites, e.g., in the gastrointestinal tract, in which their functional role still needs to be clarified. We hypothesized that caffeine evokes effects on GAS by activation of oral and gastric TAS2Rs and demonstrate that caffeine, when administered encapsulated, stimulates GAS, whereas oral administration of a caffeine solution delays GAS in healthy human subjects. Correlation analysis of data obtained from ingestion of the caffeine solution revealed an association between the magnitude of the GAS response and the perceived bitterness, suggesting a functional role of oral TAS2Rs in GAS. Expression of TAS2Rs, including cognate TAS2Rs for caffeine, was shown in human gastric epithelial cells of the corpus/fundus and in HGT-1 cells, a model for the study of GAS. In HGT-1 cells, various bitter compounds as well as caffeine stimulated proton secretion, whereby the caffeine-evoked effect was (i) shown to depend on one of its cognate receptor, TAS2R43, and adenylyl cyclase; and (ii) reduced by homoeriodictyol (HED), a known inhibitor of caffeine's bitter taste. This inhibitory effect of HED on caffeine-induced GAS was verified in healthy human subjects. These findings (i) demonstrate that bitter taste receptors in the stomach and the oral cavity are involved in the regulation of GAS and (ii) suggest that bitter tastants and bitter-masking compounds could be potentially useful therapeutics to regulate gastric pH.


Asunto(s)
Cafeína/farmacología , Ácido Gástrico/metabolismo , Células Parietales Gástricas/fisiología , Flavonas/farmacología , Humanos , Células Parietales Gástricas/metabolismo , Receptores Acoplados a Proteínas G/fisiología , Gusto
4.
Molecules ; 25(6)2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197426

RESUMEN

Background: In order to identify potential activities against periodontal diseases, eighteen dihydrochalcones and structurally related compounds were tested in an established biological in vitro cell model of periodontal inflammation using human gingival fibroblasts (HGF-1 cells). Methods: Subsequently to co-incubation of HGF-1 cells with a bacterial endotoxin (Porphyromonas gingivalis lipopolysaccharide, pgLPS) and each individual dihydrochalcone in a concentration range of 1 µM to 100 µM, gene expression of interleukin-8 (IL-8) was determined by qPCR and cellular interleukin-8 (IL-8) release by ELISA. Results: Structure-activity analysis based on the dihydrochalcone backbone and various substitution patterns at its aromatic ring revealed moieties 2',4,4',6'-tetrahydroxy 3-methoxydihydrochalcone (7) to be the most effective anti-inflammatory compound, reducing the pgLPS-induced IL-8 release concentration between 1 µM and 100 µM up to 94%. In general, a 2,4,6-trihydroxy substitution at the A-ring and concomitant vanilloyl (4-hydroxy-3-methoxy) pattern at the B-ring revealed to be preferable for IL-8 release inhibition. Furthermore, the introduction of an electronegative atom in the A,B-linker chain led to an increased anti-inflammatory activity, shown by the potency of 4-hydroxybenzoic acid N-vanillylamide (13). Conclusions: Our data may be feasible to be used for further lead structure designs for the development of potent anti-inflammatory additives in oral care products.


Asunto(s)
Antiinflamatorios , Chalconas , Fibroblastos/metabolismo , Encía/metabolismo , Interleucina-8/biosíntesis , Plomo , Antiinflamatorios/química , Antiinflamatorios/farmacología , Línea Celular , Chalconas/química , Chalconas/farmacología , Fibroblastos/patología , Encía/patología , Humanos , Plomo/química , Plomo/farmacología , Lipopolisacáridos/toxicidad , Enfermedades Periodontales/inducido químicamente , Enfermedades Periodontales/tratamiento farmacológico , Enfermedades Periodontales/metabolismo , Enfermedades Periodontales/patología , Porphyromonas gingivalis/química
5.
Matern Child Nutr ; 16(1): e12856, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31183951

RESUMEN

Child malnutrition remains persistently high in Rwanda. Complementary foods play a key role in young child nutrition. This study explores the quality and safety of complementary food products available in the Rwandan market. Ten of the most consumed porridge-type complementary food products in Rwanda have been analysed. Mean values of macronutrient and micronutrient contents were compared against three international standards and evaluated against label claims. Mean mycotoxin, microbiological, and pesticide contamination were compared with maximum tolerable limits. Mean energy density (385 kcal/100 g) and total fat content (7.9 g/100 g) were lower than all three international benchmarks. The mean fibre content of 8.5 g/100 g was above the maximum recommended amount of Codex Alimentarius and more than double the amount claimed on labels. Mean levels of vitamin A (retinyl palmitate, 0.54 mg/100 g) and vitamin E (α-tocopherol, 3.7 mg/100 g) fell significantly short of all three standards, whereas calcium and zinc requirements were only partially met. Average iron content was 12.1 mg/100 g. The analysis revealed a mean aflatoxin contamination of 61 µg/kg, and high mold and yeast infestation. Escherichia coli and pesticide residues were found, whereas no heavy metals could be quantitated. Overall, complementary food products in Rwanda show inadequate nutrient contents and high aflatoxin and microbial contamination levels. Improved regulation and monitoring of both local and imported products are needed to improve the quality and safety of complementary foods in Rwanda.


Asunto(s)
Contaminación de Alimentos , Alimentos Fortificados/análisis , Alimentos Fortificados/normas , Fenómenos Fisiológicos Nutricionales del Lactante , Valor Nutritivo , Escherichia coli , Etiquetado de Alimentos/normas , Alimentos Fortificados/microbiología , Hongos , Humanos , Lactante , Micronutrientes/análisis , Micotoxinas/análisis , Nutrientes/análisis , Necesidades Nutricionales , Plaguicidas , Rwanda , Levaduras
6.
Allergy ; 74(10): 1956-1968, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31102539

RESUMEN

BACKGROUND: The oligosaccharide galactose-α-1,3-galactose (α-Gal), present in mammalian proteins and lipids, causes an unusual delayed allergic reaction 3 to 6 hours after ingestion of mammalian meat in individuals with IgE antibodies against α-Gal. To better understand the delayed onset of allergic symptoms and investigate whether protein-bound or lipid-bound α-Gal causes these symptoms, we analyzed the capacity of α-Gal conjugated proteins and lipids to cross a monolayer of intestinal cells. METHODS: Extracts of proteins and lipids from beef were prepared, subjected to in vitro digestions, and added to Caco-2 cells grown on permeable supports. The presence of α-Gal in the basolateral medium was investigated by immunoblotting, thin-layer chromatography with immunostaining and ELISA, and its allergenic activity was analyzed in a basophil activation test. RESULTS: After addition of beef proteins to the apical side of Caco-2 cells, α-Gal containing peptides were not detected in the basolateral medium. Those peptides that crossed the Caco-2 monolayer did not activate basophils from an α-Gal allergic patient. Instead, when Caco-2 cells were incubated with lipids extracted from beef, α-Gal was detected in the basolateral medium. Furthermore, these α-Gal lipids were able to activate the basophils of an α-Gal allergic patient in a dose-dependent manner. CONCLUSION: Only α-Gal bound to lipids, but not to proteins, is able to cross the intestinal monolayer and trigger an allergic reaction. This suggests that the slower digestion and absorption of lipids might be responsible for the unusual delayed allergic reactions in α-Gal allergic patients and identifies glycolipids as potential allergenic molecules.


Asunto(s)
Enterocitos/inmunología , Enterocitos/metabolismo , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/metabolismo , Inmunoglobulina E/inmunología , Metabolismo de los Lípidos , Lípidos , Alérgenos/química , Alérgenos/inmunología , Células CACO-2 , Glucolípidos/metabolismo , Glicoproteínas/metabolismo , Humanos , Unión Proteica , Carne Roja/efectos adversos , Carne Roja/análisis
7.
Molecules ; 24(22)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739445

RESUMEN

The Western diet is characterized by a high consumption of heat-treated fats and oils. During deep-frying processes, vegetable oils are subjected to high temperatures which result in the formation of lipid peroxidation products. Dietary intake of oxidized vegetable oils has been associated with various biological effects, whereas knowledge about the effects of structurally-characterized lipid peroxidation products and their possible absorption into the body is scarce. This study investigates the impact of linoleic acid, one of the most abundant polyunsaturated fatty acids in vegetable oils, and its primary and secondary peroxidation products, 13-HpODE and hexanal, on genomic and metabolomic pathways in human gastric cells (HGT-1) in culture. The genomic and metabolomic approach was preceded by an up-to-six-hour exposure study applying 100 µM of each test compound to the apical compartment in order to quantitate the compounds' recovery at the basolateral side. Exposure of HGT-1 cells to either 100 µM linoleic acid or 100 µM 13-HpODE resulted in the formation of approximately 1 µM of the corresponding hydroxy fatty acid, 13-HODE, in the basolateral compartment, whereas a mean concentration of 0.20 ± 0.13 µM hexanal was quantitated after an equivalent application of 100 µM hexanal. An integrated genomic and metabolomic pathway analysis revealed an impact of the linoleic acid peroxidation products, 13-HpODE and hexanal, primarily on pathways related to amino acid biosynthesis (p < 0.05), indicating that peroxidation of linoleic acid plays an important role in the regulation of intracellular amino acid biosynthesis.


Asunto(s)
Aminoácidos/metabolismo , Genómica/métodos , Ácido Linoleico/metabolismo , Metabolómica/métodos , Hexanos/metabolismo , Humanos , Peroxidación de Lípido , Oxidación-Reducción
8.
J Cell Biochem ; 119(3): 2731-2741, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29052845

RESUMEN

Advanced glycation end products (AGEs), comprising a highly diverse class of Maillard reaction compounds formed in vivo and during heating processes of foods, have been described in the progression of several degenerative conditions such as Alzheimer's disease and diabetes mellitus. Nϵ -Carboxymethyllysine (CML) represents a well-characterized AGE, which is frequently encountered in a Western diet and is known to mediate its cellular effects through binding to the receptor for AGEs (RAGE). As very little is known about the impact of exogenous CML and its precursor, glyoxal, on intestinal cells, a genome-wide screening using a customized microarray was conducted in fully differentiated Caco-2 cells. After verification of gene regulation by qPCR, functional assays on fatty acid uptake, glucose uptake, and serotonin release were performed. While only treatment with glyoxal showed a slight impact on fatty acid uptake (P < 0.05), both compounds reduced glucose uptake significantly, leading to values of 81.3% ± 22.8% (500 µM CML, control set to 100%) and 68.3% ± 20.9% (0.3 µM glyoxal). Treatment with 500 µM CML or 0.3 µM glyoxal increased serotonin release (P < 0.05) to 236% ± 111% and 264% ± 66%, respectively. Co-incubation with the RAGE antagonist FPS-ZM1 reduced CML-induced serotonin release by 34%, suggesting a RAGE-mediated mechanism. Similarly, co-incubation with the SGLT-1 inhibitor phloridzin attenuated serotonin release after CML treatment by 32%, hinting at a connection between CML-stimulated serotonin release and glucose uptake. Future studies need to elucidate whether the CML/glyoxal-induced serotonin release in enterocytes might stimulate serotonin-mediated intestinal motility.


Asunto(s)
Productos Finales de Glicación Avanzada/farmacología , Glioxal/farmacología , Lisina/análogos & derivados , Serotonina/metabolismo , Células CACO-2 , Humanos , Lisina/farmacología
9.
Inorg Chem ; 57(13): 7925-7931, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-29926720

RESUMEN

In the current investigation, the reaction of Fe2(CO)9 with the ligand precursor 2-chloro-N1,N3-bis(diisopropylphosphanyl)-N1,N3-diethylbenzene-1,3-diamine (P(C-Cl)PNEt- iPr) (1) was investigated. When a suspension of Fe2(CO)9 and 1 in CH3CN was transferred in a sealed microwave glass vial and stirred for 18 h at 110 °C the complex [Fe(PCPNEt- iPr)(CO)2Cl] (2) was obtained. In an attempt to prepare the hydride Fe(II) complex [Fe(PCPNEt- iPr)(CO)2H] (3), 2 was reacted with 1 equiv of Li[HBEt3] in THF. Instead of ligand substitution, this complex underwent a one electron reduction which led to the formation of the low-spin d7 Fe(I) complex [Fe(PCPNEt- iPr)(CO)2] (4). Exposure of a benzene solution of 4 to NO gas (1 bar) at room temperature affords the diamagnetic complex [Fe(PCPNEt- iPr)(CO)(NO)] (5). This is the first iron PCP nitrosyl complex. Protonation of 5 with HBF4·Et2O affords the cationic Fe(0) complex [Fe(κ3 P,CH,P-P(CH)PNEt- iPr)(CO)(NO)]BF4 (6) which features an η2-Caryl-H agostic bond. Even with relatively weak bases such as NEt3 the agostic C-H bond can be deprotonated with reformation of the starting material 5. Therefore, protonation of 5 is completely reversible.

10.
Molecules ; 23(1)2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29351234

RESUMEN

The antioxidant activity of tocopherols in vegetable oils was shown to chiefly depend on the amount and the tocopherol homolog present. However, the most effective ratio of tocopherol homologs with regard to the antioxidant capacity has not been elucidated so far. The present study analyzed the effect of different tocopherol concentrations, homologs and ratios of homologs on markers of lipid oxidation in the most commonly consumed vegetable oils (canola, sunflower, soybean oil) stored in a 12 h light/dark cycle at 22 ± 2 °C for 56 days under retail/household conditions. After 56 days of storage, the α-tocopherol-rich canola and sunflower oil showed the strongest rise in lipid peroxides, yielding 25.1 ± 0.03 meq O2/kg (+25.3-fold) and 24.7 ± 0.05 meq O2/kg (+25.0-fold), respectively. ESR experiments, excluding effects of the oils' matrices and other minor constituents, confirmed that a food representative tocopherol ratio of (γ + δ)/α = 4.77, as represented in soybean oil, led to a more pronounced delay of lipid oxidation than a lower ratio in canola (1.39) and sunflower oil (0.06). An optimum (γ + δ)/α -tocopherol ratio contributing to the oxidative quality of vegetable oils extending their shelf life has to be investigated.


Asunto(s)
Oxidación-Reducción , Aceites de Plantas/química , Tocoferoles/química , Aldehídos/química , Antioxidantes/química , Antioxidantes/farmacología , Ácidos Grasos/química , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Peroxidación de Lípido , Temperatura , Tocoferoles/farmacología
11.
J Sci Food Agric ; 98(3): 1240-1247, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29095495

RESUMEN

BACKGROUND: The oxidative deterioration of vegetable oils is commonly measured by the peroxide value, thereby not considering the contribution of individual lipid hydroperoxide isomers, which might have different bioactive effects. Thus, the formation of 9- and 13-hydroperoxy octadecadienoic acid (9-HpODE and 13- HpODE), was quantified after short-term heating and conditions representative of long-term domestic storage in samples of linoleic acid, canola, sunflower and soybean oil, by means of stable isotope dilution analysis-liquid chromatography-mass spectroscopy. RESULTS: Although heating of pure linoleic acid at 180 °C for 30 min led to an almost complete loss of 9-HpODE and 13-HpODE, heating of canola, sunflower and soybean oil resulted in the formation of 5.74 ± 3.32, 2.00 ± 1.09, 16.0 ± 2.44 mmol L-1 13-HpODE and 13.8 ± 8.21, 10.0 ± 6.74 and 45.2 ± 6.23 mmol L-1 9-HpODE. An almost equimolar distribution of the 9- and 13-HpODE was obtained during household-representative storage conditions after 56 days, whereas, under heating conditions, an approximately 2.4-, 2.8- and 5.0-fold (P ≤ 0.001) higher concentration of 9-HpODE than 13-HpODE was detected in canola, soybean and sunflower oil, respectively. CONCLUSION: A temperature-dependent distribution of HpODE regioisomers could be shown in vegetable oils, suggesting their application as markers of lipid oxidation in oils used for short-term heating. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Aditivos Alimentarios/química , Ácidos Linoleicos/química , Ácidos Linolénicos/química , Aceites de Plantas/química , Culinaria , Almacenamiento de Alimentos , Calor , Oxidación-Reducción , Estereoisomerismo
12.
J Cell Biochem ; 117(10): 2413-22, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27137869

RESUMEN

Advanced glycation endproducts, formed in vivo, but also by the Maillard reaction upon thermal treatment of foods, have been associated with the progression of pathological conditions such as diabetes mellitus. In addition to the accumulation with age, exogenous AGEs are introduced into the circulation from dietary sources. In this study, we investigated the effects of addition of free N(ϵ) -carboxymethyllysine (CML), a well-characterized product of the Maillard reaction, on adipogenesis in 3T3-L1 preadipocytes. Treatment with 5, 50, or 500 µM CML resulted in increased lipid accumulation to similar extents, by 11.5 ± 12.6%, 12.9 ± 8.6%, and 12.8 ± 8.5%, respectively. Long-term treatment with 500 µM CML during adipogenesis resulted in increases in miR-103 and miR-143 levels, two miRNAs described to be involved in impaired glucose homeostasis and increased lipid accumulation. Furthermore, the expression of genes associated with these miRNAs, consisting of Akt1, PI3k, and Cav1 was regulated by CML. Short-term treatment of mature 3T3-L1 adipocytes with CML resulted in decreased basal glucose uptake. These results, indicate that the addition of protein-free CML to 3T3-L1 cells influence parameters associated with adipogenesis and glucose homeostasis at transcriptional, and functional level; this indicates that free CML derived from exogenous sources, in addition to protein-bound CML may be relevant in this context. J. Cell. Biochem. 117: 2413-2422, 2016. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.


Asunto(s)
Adipocitos/metabolismo , Adipogénesis/fisiología , Ácidos Grasos/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Lisina/análogos & derivados , MicroARNs/genética , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular/efectos de los fármacos , Glucosa/metabolismo , Humanos , Lisina/farmacología , Ratones , MicroARNs/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal
13.
J Nanobiotechnology ; 14: 14, 2016 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-26936369

RESUMEN

BACKGROUND: DNA microarrays are a core element of modern genomics research and medical diagnostics, allowing the simple and simultaneous determination of the relative abundances of hundreds of thousands to millions of genomic DNA or RNA sequences in a sample. Photolithographic in situ synthesis, using light projection from a digitally-controlled array of micromirrors, has been successful at both commercial and laboratory scales. The advantages of this synthesis method are its ability to reliably produce high-quality custom microarrays with a very high spatial density of DNA features using a compact device with few moving parts. The phosphoramidite chemistry used in photolithographic synthesis is similar to that used in conventional solid-phase synthesis of oligonucleotides, but some unique differences require an independent optimization of the synthesis chemistry to achieve fast and low-cost synthesis without compromising microarray quality. RESULTS: High microarray quality could be maintained while reducing coupling time to a few seconds using DCI activator. Five coupling activators were compared, which resulted in microarray hybridization signals following the order ETT > Activator 42 > DCI â‰« BTT â‰« pyridinium chloride, but only the use of DCI led to both high signal and highly uniform feature intensities. The photodeprotection time was also reduced to a few seconds by replacing the NPPOC photolabile group with the new thiophenyl-NPPOC group. Other chemical parameters, such as oxidation and washing steps were also optimized. CONCLUSIONS: Highly optimized and microarray-specific phosphoramidite chemistry, along with the use of the very photosensitive thiophenyl-NPPOC protecting group allow for the synthesis of high-complexity DNA arrays using coupling times of 15 s and deprotection times of 9 s. The resulting overall cycle time (coupling to coupling) of about 50 s, results in a three-fold reduction in synthesis time.


Asunto(s)
ADN/química , Oligonucleótidos/química , Células CACO-2 , Línea Celular Tumoral , Humanos , Luz , Hibridación de Ácido Nucleico/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Compuestos Organofosforados/química , Fotoquímica/métodos , Técnicas de Síntesis en Fase Sólida/métodos
14.
Biochim Biophys Acta ; 1840(1): 95-105, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24035785

RESUMEN

BACKGROUND: Resveratrol is a key component of red wine that has been reported to have anti-carcinogenic and anti-aging properties. Additional studies conducted in vitro and in animal models suggested anti-inflammatory properties. However, data from primary human immune cells and in vivo studies are limited. METHODS: A pilot study was performed including 10 healthy volunteers. Plasma cytokine levels were measured over 48h after oral application of 5g resveratrol. To verify the in vivo findings, cytokine release and gene expression in human peripheral blood mononuclear cells (PBMC) and/or monocytes was assessed after treatment with resveratrol or its metabolites and stimulation with several toll-like receptor (TLR)-agonists. Additionally, the impact on intracellular signaling pathways was analyzed using a reporter cell line and Western blotting. RESULTS: Resveratrol treated individuals showed a significant increase in tumor necrosis factor-α (TNF-α) levels 24h after treatment compared to baseline. Studies using human PBMC or isolated monocytes confirmed potentiation of TNF-α production with different TLR agonists, while interleukin (IL)-10 was inhibited. Moreover, we observed significantly enhanced nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NF-κB) activation using a reporter cell line and found increased phosphorylation of p105, which is indicative of alternative NF-κB pathway activation. GENERAL SIGNIFICANCE: By administering resveratrol to healthy humans and utilizing primary immune cells we were able to detect TNF-α enhancing properties of the agent. In parallel, we found enhanced alternative NF-κB activation. We report on a novel pro-inflammatory property of resveratrol which has to be considered in concepts of its biologic activity.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Proliferación Celular/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Monocitos/metabolismo , Estilbenos/administración & dosificación , Factor de Necrosis Tumoral alfa/metabolismo , Administración Oral , Adolescente , Adulto , Antiinflamatorios no Esteroideos/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Células Cultivadas , Citocinas/metabolismo , Voluntarios Sanos , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/microbiología , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/inmunología , Monocitos/microbiología , FN-kappa B/genética , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , Proyectos Piloto , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Resveratrol , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología , Factor de Necrosis Tumoral alfa/genética , Adulto Joven
15.
J Cell Biochem ; 116(6): 1153-63, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25704235

RESUMEN

Red pepper and its major pungent principle, capsaicin (CAP), have been shown to be effective anti-obesity agents by reducing energy intake, enhancing energy metabolism, decreasing serum triacylglycerol content, and inhibiting adipogenesis via activation of the transient receptor potential cation channel subfamily V member 1 (TRPV1). However, the binding of CAP to the TRPV1 receptor is also responsible for its pungent sensation, strongly limiting its dietary intake. Here, the effects of a less pungent structural CAP-analog, nonivamide, on adipogenesis and underlying mechanisms in 3T3-L1 cells were studied. Nonivamide was found to reduce mean lipid accumulation, a marker of adipogenesis, to a similar extent as CAP, up to 10.4% (P < 0.001). Blockage of the TRPV1 receptor with the specific inhibitor trans-tert-butylcyclohexanol revealed that the anti-adipogenic activity of nonivamide depends, as with CAP, on TRPV1 receptor activation. In addition, in cells treated with nonivamide during adipogenesis, protein levels of the pro-adipogenic transcription factor peroxisome-proliferator activated receptor γ (PPARγ) decreased. Results from miRNA microarrays and digital droplet PCR analysis demonstrated an increase in the expression of the miRNA mmu-let-7d-5p, which has been associated with decreased PPARγ levels.


Asunto(s)
Adipogénesis/efectos de los fármacos , Capsaicina/análogos & derivados , MicroARNs/metabolismo , PPAR gamma/metabolismo , Células 3T3-L1 , Animales , Capsaicina/farmacología , Ratones , Canales Catiónicos TRPV/metabolismo
16.
Croat Med J ; 56(2): 94-103, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25891868

RESUMEN

AIM: To assess the impact of prenatal exposure to Maillard reaction products (MRPs) -rich diet and postnatal Coca-Cola consumption on metabolic status of female rats. Diet rich in MRPs and consumption of saccharose/fructose sweetened soft drinks is presumed to impose increased risk of development of cardiometabolic afflictions, such as obesity or insulin resistance. METHODS: At the first day of pregnancy, 9 female Wistar rats were randomized into two groups, pair-fed either with standard rat chow (MRP-) or MRPs-rich diet (MRP+). Offspring from each group of mothers was divided into two groups and given either water (Cola-) or Coca-Cola (Cola+) for drinking ad libitum for 18 days. Oral glucose tolerance test was performed, and circulating markers of inflammation, oxidative stress, glucose and lipid metabolism were assessed. RESULTS: MRP+ groups had higher weight gain, significantly so in the MRP+/Cola- vs MRP-/Cola-. Both prenatal and postnatal intervention increased carboxymethyllysine levels and semicarbazide-sensitive amine oxidase activity, both significantly higher in MRP+/Cola + than in MRP-/Cola-. Total antioxidant capacity was lower in MRP+ groups, with significant decrease in MRP+/Cola + vs MRP-/Cola+. Rats drinking Coca-Cola had higher insulin, homeostatic model assessment of insulin resistance, heart rate, advanced oxidation of protein products, triacylglycerols, and oxidative stress markers measured as thiobarbituric acid reactive substances compared to rats drinking water, with no visible effect of MRPs-rich diet. CONCLUSION: Metabolic status of rats was affected both by prenatal and postnatal dietary intervention. Our results suggest that combined effect of prenatal MRPs load and postnatal Coca-Cola drinking may play a role in development of metabolic disorders in later life.


Asunto(s)
Bebidas Gaseosas , Dieta , Reacción de Maillard , Enfermedades Metabólicas/etiología , Efectos Tardíos de la Exposición Prenatal/etiología , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Femenino , Prueba de Tolerancia a la Glucosa , Metabolismo de los Lípidos , Enfermedades Metabólicas/sangre , Estrés Oxidativo , Embarazo , Fenómenos Fisiologicos de la Nutrición Prenatal , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
17.
Arch Anim Nutr ; 69(5): 378-98, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26305386

RESUMEN

The aim of the present study was to evaluate the influence of native, fermented and extruded wheat bran on the performance and intestinal morphology of piglets. Additionally, short-chain fatty acids (SCFA), biogenic amines, ammonia, lactic acid, pH as well as E. coli and lactic acid bacterial counts were analysed in digesta samples from three gut sections. Furthermore, the antioxidant potential in blood samples was evaluated based on the lipid radicals formed. For this purpose, 48 newly weaned piglets (28 d old) were allocated to one of the four different dietary treatment groups: no wheat bran (Control), native wheat bran, fermented wheat bran as well as extruded wheat bran. Wheat bran variants were included at 150 g/kg into the diets. All diets were mixed to reach the calculated isonitrogenic nutrient contents. Gut tissue and digesta samples were collected from the proximal jejunum, the terminal ileum and the colon ascendens, blood samples directly at slaughter. Although none of the dietary interventions had an impact on performance parameters, the amount of goblet cells in the ileum was increased upon feeding native and extruded wheat bran, compared to fermented bran (p < 0.05). The E. coli counts in colonic chyme were significantly lower (p < 0.05) in the Control group compared to the groups fed with wheat bran. The concentration of SCFA showed differences for minor compounds (p < 0.05), while linear contrast analyses revealed a reduced concentration of total SCFA in the colon following the feeding of modified wheat bran compared to native wheat bran. This may suggest that several compounds are more easily digested already in the ileum, resulting in a reduced nutrient flow into the large intestine and therefore less unexploited digesta is available as substrate for the microorganisms there. Fermentation also resulted in a significant decrease of methylamine in the colon (p < 0.05), while other biogenic amines in the ileum and colon showed no statistically significant differences. The formation of lipid radicals was decreased (p < 0.05) after feeding native wheat bran compared to the Control group. These results suggest that fermentation and extrusion of wheat bran exert some different impact regarding their physiological mode of action.


Asunto(s)
Alimentación Animal/análisis , Fibras de la Dieta/metabolismo , Tracto Gastrointestinal/efectos de los fármacos , Sus scrofa/anatomía & histología , Sus scrofa/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Fibras de la Dieta/deficiencia , Fermentación , Tracto Gastrointestinal/anatomía & histología , Sus scrofa/crecimiento & desarrollo
18.
Angew Chem Int Ed Engl ; 54(29): 8555-9, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26036777

RESUMEN

Light as an external trigger is a valuable and easily controllable tool for directing chemical reactions with high spatial and temporal accuracy. Two o-nitrobenzyl derivatives, benzoyl- and thiophenyl-NPPOC, undergo photo-deprotection with significantly improved efficiency over that of the commonly used NPPOC group. The two- and twelvefold increase in photo-deprotection efficiency was proven using photolithograph synthesis of microarrays.


Asunto(s)
Nitrobencenos/química , Luz , Análisis por Micromatrices , Fotólisis
19.
Hum Psychopharmacol ; 29(6): 537-43, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25087849

RESUMEN

BACKGROUND: Oxidative stress can result in damage to the brain and other organs. To protect from oxidative damage, the human body possesses molecular defense systems, based on the activity of antioxidants, and enzymatic defense systems, including the enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). Although pre-clinical research has shown that stimulant use is associated with oxidative damage, oxidative stress and the antioxidant defense systems have not been evaluated in clinical samples of stimulant-dependent patients. OBJECTIVES: This study aimed to investigate the link between stimulant dependence and oxidative stress. METHODS: Peripheral blood samples from 174 methamphetamine (n = 48) and/or cocaine-dependent (n = 126) participants as well as 30 normal control participants were analyzed for the enzyme activities of CAT, SOD, and GSH-Px in the erythrocytes and the total antioxidant capacity and the malondialdehyde concentration in the plasma. RESULTS: We could show an association of stimulant dependence with a depletion of total antioxidant capacity to 54.6 ± 4.7%, which correlates with a reduced activity of the SOD to 71.3 ± 0.03% compared with healthy control participants (100%). CONCLUSION: Stimulant-dependent patients had significantly lower antioxidant capacity relative to controls, suggesting that they may be at greater risk for oxidative damage to the brain and other organs.


Asunto(s)
Trastornos Relacionados con Anfetaminas/sangre , Trastornos Relacionados con Cocaína/sangre , Estrés Oxidativo , Adulto , Catalasa/sangre , Estimulantes del Sistema Nervioso Central/administración & dosificación , Cocaína/administración & dosificación , Eritrocitos/efectos de los fármacos , Eritrocitos/enzimología , Femenino , Glutatión Peroxidasa/sangre , Humanos , Masculino , Malondialdehído/sangre , Metanfetamina/administración & dosificación , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Superóxido Dismutasa/sangre
20.
Int J Food Sci Nutr ; 65(2): 219-25, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24111510

RESUMEN

Advanced glycation end products (AGEs) are stable end products of the Maillard reaction. Effects of food extracts are often initially analysed in cellular test systems and it is not clear how different cell culture conditions might influence the results. Therefore, we compared the effects of two models for AGE-rich food, bread crust and coffee extract (CE) on WI-38 human lung fibroblasts under different cell culture conditions (sub-confluent versus confluent cells, with and without serum). WI-38 cells responded to coffee and bread crust extract (BCE) with a rapid phosphorylation of PKB (AKT), p42/44 MAPK (ERK 1/2) and p38 MAPK, strongly depending on culture conditions. BCE resulted in increased cell numbers, whereas CE appeared to be cytotoxic. When cell numbers under all culture conditions and treatments were correlated with kinase phosphorylation, the relation between phospho-p38 MAPK and phospho-AKT represented a good, cell culture condition-independent predictor of cell survival.


Asunto(s)
Pan , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Café , Fibroblastos/efectos de los fármacos , Productos Finales de Glicación Avanzada , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Línea Celular , Células Cultivadas , Humanos , Pulmón/citología , Pulmón/efectos de los fármacos , Reacción de Maillard , Fosforilación , Preparaciones de Plantas/farmacología
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