RESUMEN
Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.
Asunto(s)
Colon , Depsidos , Digestión , Fermentación , Ilex paraguariensis , Extractos Vegetales , Polifenoles , Ácido Rosmarínico , Rosmarinus , Animales , Humanos , Extractos Vegetales/metabolismo , Rosmarinus/química , Ratas , Ilex paraguariensis/química , Porcinos , Depsidos/metabolismo , Depsidos/análisis , Polifenoles/metabolismo , Polifenoles/análisis , Colon/metabolismo , Colon/microbiología , Masculino , Cinamatos/metabolismo , Cinamatos/análisis , Microbioma Gastrointestinal , Té/química , Ácido Quínico/análogos & derivados , Ácido Quínico/metabolismo , Ácido Quínico/análisis , Catequina/análogos & derivados , Catequina/metabolismo , Catequina/análisis , Cromatografía Líquida de Alta Presión , Camellia sinensis/químicaRESUMEN
Epicatechin is a polyphenol compound that promotes skeletal muscle differentiation and counteracts the pathways that participate in the degradation of proteins. Several studies present contradictory results of treatment protocols and therapeutic effects. Therefore, the objective of this systematic review was to investigate the current literature showing the molecular mechanism and clinical protocol of epicatechin in muscle atrophy in humans, animals, and myoblast cell-line. The search was conducted in Embase, PubMed/MEDLINE, Cochrane Library, and Web of Science. The qualitative analysis demonstrated that there is a commonness of epicatechin inhibitory action in myostatin expression and atrogenes MAFbx, FOXO, and MuRF1. Epicatechin showed positive effects on follistatin and on the stimulation of factors related to the myogenic actions (MyoD, Myf5, and myogenin). Furthermore, the literature also showed that epicatechin can interfere with mitochondrias' biosynthesis in muscle fibers, stimulation of the signaling pathways of AKT/mTOR protein production, and amelioration of skeletal musculature performance, particularly when combined with physical exercise. Epicatechin can, for these reasons, exhibit clinical applicability due to the beneficial results under conditions that negatively affect the skeletal musculature. However, there is no protocol standardization or enough clinical evidence to draw more specific conclusions on its therapeutic implementation.
Asunto(s)
Catequina , Animales , Humanos , Catequina/farmacología , Catequina/uso terapéutico , Catequina/metabolismo , Fibras Musculares Esqueléticas , Músculo Esquelético/metabolismo , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Proteína MioD/metabolismo , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Oxidative stress and inflammation play a key role in diverse pathological conditions such as cancer and metabolic disorders. The objective of this study was to determine the antioxidant and anti-inflammatory potentials of crude extract (CE) and phenolic-enriched extract (PHE) obtained from the seed coats (SCs) of black bean (BB) and pinto bean (PB) varieties. Delphinidin-3-O-glucoside (46 mg/g SC), malvidin-3-O-glucoside (29.9 mg/g SC), and petunidin-3-O-glucoside (7.5 mg/g SC) were found in major concentrations in the PHE-BB. Pelargonidin (0.53 mg/g SC) was only identified in the PHE-PB. PHE from both varieties showed antioxidant and radical scavenging capacities, with strong correlations associated with total phenolic content (TPC). Polyphenolics, including catechin, myricetin, kaempferol, quercetin, and isorhamnetin glucosides, were identified in the extracts. In terms of the anti-inflammatory potentials, PHE-PB had an IC50 of 10.5 µg dry extract/mL (µg DE/mL) for cyclooxygenase-2 (COX-2) inhibition. The inhibition values for cyclooxygenase-1 (COX-1) ranged from 118.1 to 162.7 µg DE/mL. Regarding inducible nitric oxide synthase (iNOS) inhibition, PHE-BB had an IC50 of 62.6 µg DE/mL. As determined via in silico analysis, pelargonidin showed binding affinities of -7.8 and -8.5 kcal/mol for COX-1 and iNOS, respectively, and catechin had a value of -8.3 kcal/mol for COX-2. Phenolic-enriched extracts from seed coats of black and pinto beans showed good antioxidant and anti-inflammatory potential that warrants in vitro and in vivo studies.
Asunto(s)
Catequina , Phaseolus , Phaseolus/química , Antioxidantes/química , Extractos Vegetales/química , Ciclooxigenasa 2/metabolismo , Catequina/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/metabolismo , Fenoles/análisis , Glucósidos/metabolismoRESUMEN
Our objective was to determine whether (-)-Epicatechin administered alone or simultaneously with topical Ketorolac decreased the relative expression of GFAP and modulated the response of Nrf2 in a mouse model with induced hyperglycemia. We found that GFAP and Nrf2 decreased in the groups that received treatments alone or simultaneous during 8 weeks; even when the effect on the Nrf2 was not pronounced, it showed a higher concentration when GFAP decreased. Our results suggest a protective effect of Ketorolac and (-) - Epicatechin, which seem to limit the preclinical retinal damage caused by inflammation in hyperglycemia.
Asunto(s)
Catequina , Hiperglucemia , Enfermedades de la Retina , Animales , Ratones , Catequina/farmacología , Catequina/uso terapéutico , Catequina/metabolismo , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/metabolismo , Ketorolaco/uso terapéutico , Ketorolaco/metabolismo , Ketorolaco/farmacología , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Retina/metabolismoRESUMEN
This review summarizes experimental evidence on the beneficial effects of ( -)-epicatechin (EC) attenuating major cardiometabolic risk factors, i.e., dyslipidemias, obesity (adipose tissue dysfunction), hyperglycemia (insulin resistance), and hypertension (endothelial dysfunction). Studies in humans are revised and complemented with experiments in animal models, and cultured cells, aiming to understand the molecular mechanisms involved in EC-mediated effects. Firstly, an assessment of EC metabolism gives relevance to both conjugated-EC metabolites product of host metabolism and microbiota-derived species. Integration and analysis of results stress the maintenance of redox homeostasis and mitigation of inflammation as relevant processes associated with cardiometabolic diseases. In these processes, EC appears having significant effects regulating NADPH oxidase (NOX)-dependent oxidant production, nitric oxide (NO) production, and energy homeostasis (mitochondrial biogenesis and function). The potential participation of cell membranes and membrane-bound receptors is also discussed in terms of direct molecular action of EC and EC metabolites reaching cells and tissues.
Asunto(s)
Factores de Riesgo Cardiometabólico , Catequina/farmacología , Animales , Catequina/química , Catequina/metabolismo , Catequina/uso terapéutico , Dislipidemias/tratamiento farmacológico , Humanos , Hiperglucemia/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Obesidad/tratamiento farmacológicoRESUMEN
Impairing osteoporosis progression is a challenge, and recently the role of antioxidants has been associated to bone metabolism. Green tea extract is rich in catechins, especially epigallocatechin gallate (EGCG), which may help control osteoporosis damage in bone tissue. This investigation evaluated the efficacy of green tea ingestion containing different concentrations of EGCG in calvaria bone repair of ovariectomized rats. Wistar rats (n=15) were ovariectomized and divided into 3 groups: ovariectomized (OVX), ovariectomized + GTE 15 % EGCG (OVX/GTE15), and ovariectomized + GTE 94 % EGCG (OVX/GTE94). Green tea extract was administered by gavage in the concentration of 50 mg/kg and sham group (n=5) received water. Bone defects were performed in the calvaria 60 days after ovariectomy followed by 4 weeks until euthanasia. Bone samples were collected to perform qualitative and quantitative histological analysis of bone formation. Data obtained were submitted to normality and ANOVA statistical test for p<0.05. The mean values of neoformed bone for Sham, OVX, OVX/GTE15 and OVX/GTE94 were respectively: 21.11 ± 3.91; 19.92 ± 2.20; 33.05 ± 1.26 e 34.75 ± 0.54 (p<0.05). Results show that continuous ingestion of green tea extract immediately after ovariectomy shows positive effects in the prevention of bone loss in osteoporosis, even with low concentrations of EGCG.
La disminución en la progresión de la osteoporosis es un desafío, y recientemente el papel de los antioxidantes se ha asociado al metabolismo óseo. El extracto de té verde es rico en catequinas, especialmente el galato de epigalocatequina (EGCG), lo que puede ayudar a controlar el daño de la osteoporosis en el tejido óseo. Esta investigación evaluó la eficacia de la ingesta de té verde con diferentes concentraciones de EGCG en la reparación ósea de calvaria de ratas ovariectomizadas. Las ratas Wistar (n = 15) fueron ovariectomizadas y divididas en 3 grupos: ovariectomizadas (OVX), ovariectomizadas + GTE 15 % EGCG (OVX / GTE15), y ovariectomizadas + GTE 94 % EGCG (OVX / GTE94). El extracto de té verde se administró por sonda en una concentración de 50 mg/kg y el grupo simulado (n = 5) recibió agua. Los defectos óseos se realizaron en la calvaria 60 días después de la ovariectomía, seguido de 4 semanas hasta la eutanasia. Se obtuvieron muestras de hueso para realizar un análisis histológico cualitativo y cuantitativo de la formación ósea. Los datos obtenidos se sometieron a normalidad y prueba estadística ANOVA (p<0,05). Los valores medios de hueso neoformado para Sham, OVX, OVX / GTE15 y OVX / GTE94 fueron: 21,11 ± 3,91; 19,92 ± 2,20; 33,05 ± 1,26 y 34,75 ± 0,54 (p <0,05), respectivamente. Los resultados muestran que la ingesta continua de extracto de té verde, inmediatamente después de la ovariectomía, muestra efectos positivos en la prevención de la pérdida ósea ocurrida en la osteoporosis, incluso con concentraciones bajas de EGCG.
Asunto(s)
Animales , Femenino , Ratas , Té/química , Regeneración Ósea , Extractos Vegetales/farmacología , Catequina/análogos & derivados , Catequina/metabolismo , Osteoporosis/patología , Osteoporosis/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Ovariectomía , Ratas WistarRESUMEN
Small unilamellar and multilayered liposomes loaded with polymeric (epi)catechins up to pentamers were produced. The bioaccessibility, kinetic release profile, and degradation under in vitro gastrointestinal conditions were monitored by UHPLC-DAD-QTOF-MS/MS. The results show that all of the procyanidins underwent depolymerization and epimerization into small molecular oligomers and mainly to (epi)catechin subunits. Moreover, all of the liposome formulations presented higher bioaccessibility and antioxidant activity in comparison to their respective counterparts in non-encapsulated form. Similar results were obtained with procyanidins from cocoa extract-loaded liposomes. Namely, the bioaccessibility of dimer, trimer, and tetramer fractions from cocoa-loaded liposomes were 4.5-, 2.1-, and 9.3-fold higher than those from the non-encapsulated cocoa extract. Overall, the procyanidin release profile was dependent on their chemical structure and physicochemical interaction with the lipid carrier. These results confirmed that liposomes are efficient carriers to stabilize and transport procyanidins with the aim of enhancing their bioaccessibility at a controlled release rate.
Asunto(s)
Antioxidantes/metabolismo , Liposomas , Proantocianidinas/metabolismo , Proantocianidinas/farmacocinética , Disponibilidad Biológica , Proteínas de Unión al Calcio/química , Catequina/metabolismo , Fenómenos Químicos , Digestión , Estabilidad de Medicamentos , Cinética , Liposomas/química , Liposomas/metabolismo , Microscopía Electrónica de Transmisión , Estructura Molecular , Pancreatina/metabolismo , Pepsina A/metabolismo , Proantocianidinas/química , Factores de TranscripciónRESUMEN
Inflammation involves the activation of redox-sensitive transcription factors, e.g., nuclear factor κB (NF-κB). Administration of (-)-epicatechin to high-fructose-fed rats prevented NF-κB activation and up-regulation of the NADPH oxidase 4 (NOX4) in the kidney cortex. These results add mechanistic insights into the action of (-)-epicatechin diminishing inflammatory responses.
Asunto(s)
Catequina/metabolismo , Fructosa/metabolismo , Corteza Renal/enzimología , NADPH Oxidasa 1/metabolismo , NADPH Oxidasa 4/metabolismo , FN-kappa B/metabolismo , Animales , Corteza Renal/metabolismo , Masculino , NADPH Oxidasa 1/genética , NADPH Oxidasa 2/genética , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/genética , FN-kappa B/genética , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismoRESUMEN
Liposomes containing theobromine, caffeine, catechin, epicatechin, and a cocoa extract were fabricated using microfluidization and sonication. A high encapsulation efficiency and good physicochemical stability were obtained by sonication (75% amplitude, 7 min). Liposomes produced at pH 5.0 had mean particle diameter ranging from 73.9 to 84.3 nm. The structural and physicochemical properties of the liposomes were characterized by transmission electron microscopy, confocal fluorescence microscopy, and antioxidant activity assays. The release profile was measured by ultra-high performance liquid chromatography coupled to diode array detection. The bioaccessibility of the bioactive compounds encapsulated in liposomes was determined after exposure to a simulated in vitro digestion model. Higher bioaccessibilities were measured for all catechins-loaded liposome formulations as compared to nonencapsulated counterparts. These results demonstrated that liposomes are capable of increasing the bioaccessibility of flavan-3-ols, which may be important for the development of nutraceutical-enriched functional foods.
Asunto(s)
Alcaloides/química , Cacao/química , Catequina/química , Liposomas/química , Extractos Vegetales/química , Alcaloides/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Catequina/metabolismo , Digestión , Flavonoides/química , Flavonoides/metabolismo , Humanos , Liposomas/metabolismo , Modelos Biológicos , Extractos Vegetales/metabolismoRESUMEN
Grape pomace extract (GPE) is a rich and relatively low-cost source of phenolic compounds. However, little is known about the main GPE metabolites in mammals, which could help explain the observed health-promoting effects. This study investigated the presence of parent compounds from flavanol, flavonol and stilbene families and their metabolites in rat plasma and tissues after an acute intake of GPE in doses of 300 and 600â¯mgâ¯kg/body weight. The measurement of free compounds and their metabolites was performed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results showed the presence of epicatechin, epicatechin methyl-glucuronide, epicatechin methyl-sulphate, catechin, catechin-glucuronide, quercetin methyl-glucuronide, resveratrol-3-glucuronide, resveratrol-4-glucuronide and resveratrol-3-sulphate in plasma, which was dose dependent. The most abundant measured compound in plasma was epicatechin-glucuronide. The presence of glucuronidated and methyl-glucuronidated forms of catechin were observed in the liver at both doses, while epicatechin-glucuronide and methyl-glucuronide were detected only upon intake of 600â¯mg GPE/kg body weight. At this dose epicatechin-glucuronide and methyl-glucuronide were also detected in muscle, and catechin methyl-glucuronide in adipose tissue. Results show the main GPE metabolites present in rat tissues after oral consumption, contributing to better understand the health benefits of GPE and its potential utilization as a functional ingredient.
Asunto(s)
Flavonoides/sangre , Flavonoides/metabolismo , Fenoles/sangre , Fenoles/metabolismo , Extractos Vegetales/metabolismo , Vitis/metabolismo , Animales , Catequina/análisis , Catequina/sangre , Catequina/metabolismo , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Masculino , Fenoles/análisis , Extractos Vegetales/administración & dosificación , Quercetina/análisis , Quercetina/sangre , Quercetina/metabolismo , Ratas Wistar , Resveratrol/análisis , Resveratrol/sangre , Resveratrol/metabolismo , Espectrometría de Masas en TándemRESUMEN
Grapes are widely produced in northwestern Mexico, generating many wood trimmings (vineyard prunings) that have no further local use. This makes vineyard prunings a very attractive alternative for the cultivation of white-rot medicinal mushrooms such as Lentinus edodes. This type of wood can also offer a model for the evaluation of oxidative enzyme production during the fermentation process. We tested the effect of wood from vineyard prunings on the vegetative growth of and production of ligninolytic enzymes in L. edodes in solid-state fermentation and with wheat straw as the control substrate. The specific growth rate of the fungus was 2-fold higher on vineyard pruning culture (µM = 0.95 day-1) than on wheat straw culture (µM = 0.47 day-1). Laccase-specific production was 4 times higher in the vineyard prunings culture than on wheat straw (0.34 and 0.08 mU · mg protein-1 · ppm CO2-1, respectively), and manganese peroxidase production was 3.7 times higher on wheat straw culture than on vineyard prunings (2.21 and 0.60 mU · mg protein-1 · ppm CO2-1, respectively). To explain accurately these differences in growth and ligninolytic enzyme activity, methanol extracts were obtained from each substrate and characterized. Resveratrol and catechins were the main compounds identified in vineyard prunings, whereas epigallocatechin was the only one detected in wheat straw. Compounds susceptible to enzymatic oxidation are more bioavailable in vineyard prunings than in wheat straw, and thus the highest L. edodes growth rate is associated with the presence of these compounds.
Asunto(s)
Fermentación , Fitoquímicos/metabolismo , Hongos Shiitake/crecimiento & desarrollo , Disponibilidad Biológica , Catequina/análogos & derivados , Catequina/aislamiento & purificación , Catequina/metabolismo , Lacasa/análisis , México , Oxidación-Reducción , Peroxidasas/análisis , Fitoquímicos/aislamiento & purificación , Tallos de la Planta/metabolismo , Tallos de la Planta/microbiología , Resveratrol , Hongos Shiitake/enzimología , Hongos Shiitake/metabolismo , Estilbenos/aislamiento & purificación , Estilbenos/metabolismo , Triticum/metabolismo , Triticum/microbiología , Vitis/metabolismo , Vitis/microbiologíaRESUMEN
The interaction of enterodiol and the well-described polyphenol epigallocatechin gallate (EGCG) with hepatic membranes has been matter of interest in the last few years. On one hand, EGCG is only able to bind to the phospholipid polar head groups, as it has been already described in synthetic lipid bilayers and erythrocyte membranes but cannot get inserted into the hydrophobic core or be transported into the lumen of membrane vesicles. On the other, enterodiol has no interaction with non-energized membranes either, but it is able to interact and even be transported upon addition of ATP. In fact, the ATPase activity undergoes a twofold increase in the presence of enterodiol but not in the presence of EGCG. This is the first report on the transport of enterodiol by liver membranes, and it may help explain the rather high blood concentrations of this estrogenic enterolignan compared to EGCG, which is extensively metabolized by the intestine and the liver. The present results suggest that a fraction of enterodiol may escape the liver inactivation by being pumped out from the hepatocytes to the bloodstream.
Asunto(s)
Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/metabolismo , Membrana Celular/metabolismo , Lignanos/metabolismo , Membrana Dobles de Lípidos/química , Hígado/metabolismo , Polifenoles/química , Polifenoles/metabolismo , Animales , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , RatasRESUMEN
The production of nitric oxide (NO) by nitric oxide synthases (NOS) depends on the bioavailability of L-arginine as NOS competes with arginase for this common substrate. As arginase activity increases, less NO is produced and adverse cardiovascular consequences can emerge. (-)-Epicatechin (EPI), the most abundant flavonoid in cacao, has been reported to stimulate endothelial and neuronal NOS expression and function leading to enhanced vascular function and cardioprotective effects. However, little is known about the effects of EPI on myocardial arginase activity. The aim of the present study was to determine if EPI is able to interact and modulate myocardial arginase and NOS expression and activity. For this purpose, in silico modeling, in vitro activity assays and a rat model of ischemia/reperfusion injury were used. In silico and in vitro results demonstrate that EPI can interact with arginase and significantly decrease its activity. In vivo, 10 days of EPI pretreatment reduces ischemic myocardium arginase expression while increasing NOS expression and phosphorylation levels. Altogether, these results may partially account for the cardioprotective effects of EPI.
Asunto(s)
Arginasa/antagonistas & inhibidores , Cardiotónicos/farmacología , Catequina/farmacología , Inhibidores Enzimáticos/farmacología , Daño por Reperfusión/enzimología , Daño por Reperfusión/prevención & control , Animales , Arginasa/química , Arginasa/metabolismo , Catequina/metabolismo , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/metabolismo , Simulación del Acoplamiento Molecular , Miocardio/enzimología , Óxido Nítrico Sintasa/metabolismo , Conformación ProteicaRESUMEN
Maternal deprivation (MD) in early life affects the development of the brain, causing cognitive losses in adulthood. Oxidative imbalance may be one of the factors that trigger these deficits. Therapies with antioxidant components, like green tea from Camellia sinensis (GT) has been used to treat or prevent memory deficits in a variety of conditions related to oxidative stress. Here we demonstrate that memory deficits caused by MD can be prevented by GT antioxidant activity in hippocampus. Pregnant female rats were used. Her puppies were submitted to MD and intake of GT. Recognition and aversive memory were evaluated, as well as hippocampal oxidative status. Data showed that MD prejudice short and long-term recognition and aversive memory and that GT protected memory. Hippocampal reactive oxygen species levels were increased in MD rats; this increase was avoided by GT supplementation. GSH was decreased on hippocampus MD rats. GT did not avoid GSH decrease, but promote the increase of total antioxidant capacity in MD rats' hippocampus. In conclusion, GT protects against memory deficits related to MD, and one of the implicated mechanism seems to be the antioxidant effects of GT.
Asunto(s)
Camellia sinensis/metabolismo , Privación Materna , Trastornos de la Memoria/etiología , Trastornos de la Memoria/prevención & control , Acetilcolinesterasa/metabolismo , Factores de Edad , Análisis de Varianza , Animales , Animales Recién Nacidos , Camellia sinensis/química , Catequina/metabolismo , Cromatografía Líquida de Alta Presión , Conducta Exploratoria/fisiología , Femenino , Glutatión/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Umbral del Dolor/fisiología , Embarazo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Reconocimiento en Psicología/fisiologíaRESUMEN
Natural variation of Andean potato was used to study the biosynthesis of phenolic compounds. Levels of phenolic compounds and corresponding structural gene transcripts were examined in flesh and skin of tubers. Phenolic acids, mainly chlorogenic acid (CGA), represent the major compounds, followed by anthocyanins and flavan-3-ols. High-anthocyanin varieties have high levels of CGA. Both metabolite and transcript levels were higher in skin than in flesh and showed a good correspondence. Two hydroxycinnamoyl-CoA transferases (HCT/HQT) have been involved in CGA production, of which HCT reflects CGA levels. Catechin was found in pigmented tissues whereas epicatechin was restricted to tuber skin. Transcripts of leucoanthocyanidin reductase (LCR), which generates catechin, could not be detected. Anthocyanidin reductase (ANR) transcripts, the enzyme responsible for epicatechin production, showed similar levels among samples. These data suggest that the biosynthesis of flavan-3-ols in potato tuber would require ANR but not LCR and that an epimerization process is involved.
Asunto(s)
Antocianinas/biosíntesis , Ácido Clorogénico/metabolismo , Flavonoides/biosíntesis , Tubérculos de la Planta/metabolismo , Solanum tuberosum/metabolismo , Antocianinas/análisis , Argentina , Catequina/análisis , Catequina/metabolismo , Ácido Clorogénico/análisis , Flavonoides/análisis , Fenoles/análisis , Fenoles/metabolismo , Tubérculos de la Planta/química , Polifenoles/análisis , Polifenoles/metabolismo , Solanum tuberosum/químicaRESUMEN
Tea leaves are rich in plant secondary phenolics, especially flavonoids. Catechins are considered to be the most valuable flavonoids, and the catechin content in tea is an important trait for determining its quality. We have developed cleaved amplified polymorphic sequence (CAPS)-based markers for evaluating total catechin content that target two important secondary metabolite pathway genes, PAL (phenylalanine ammonia-lyase) and CHS (chalcone synthase). Catechin content levels in the tea samples tested ranged from 9 to 33 mg/mg. The CAPS technique identified clones with the homozygous profile PRc1, which has relatively lower catechin content than clones with the heterozygous profile PRc2. A significant difference (t = 16.85) in the level of catechin content was also detected between heterozygotes and homozygotes in the tea seed stock TS379. We found a polynomial relationship between the marker developed for CHS2 and catechin content in these tea samples with R2 = 0.9788. Moreover, PAL has less of a relationship with catechin content. Therefore, we recommend tea clones with heterozygous CAPS profiles for the gene CHS2+RcaI for the further improvement in these clones.
Asunto(s)
Aciltransferasas/genética , Camellia sinensis/genética , Catequina/aislamiento & purificación , Fenilanina Amoníaco-Liasa/genética , Té/genética , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Catequina/genética , Catequina/metabolismo , Flavonoides/aislamiento & purificación , Flavonoides/metabolismo , Marcadores Genéticos , India , Fenotipo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Té/crecimiento & desarrollo , Té/metabolismoRESUMEN
Parkinson's disease is a neurodegenerative disorder characterized by movement alterations caused by reduced dopaminergic neurotransmission in the nigrostriatal pathway, presumably by oxidative stress (OS). MPP(+) intrastriatal injection leads to the overproduction of free radicals (FR). The increasing formation of FR produces OS, a decline in dopamine (DA) content, and behavioral disorders. Epicatechin (EC) has shown the ability to be FR scavenger, an antioxidant enzyme inductor, a redox state modulator, and transition metal chelator. Acute administration of 100 mg/kg of EC significantly prevented (P < 0.05) the circling MPP(+)-induced behavior (10 µg/8 µL). Likewise, EC significantly (P < 0.05) reduced the formation of fluorescent lipid products caused by MPP(+). MPP(+) injection produced (P < 0.05) increased enzymatic activity of the constitutive nitric oxide synthase (cNOS). This effect was blocked with acute EC pretreatment. Cu/Zn-dependent superoxide dismutase (Cu/Zn-SOD) activity was significantly (P < 0.05) reduced as a consequence of MPP(+) damage. EC produced a slight increase (≈20%) in Cu/Zn-SOD activity in the control group. Such effects persisted in animals injured with MPP(+). The results show that EC is effective against MPP(+)-induced biochemical and behavioral damage, which is possible by an increase in Cu/Zn-SOD activity.
Asunto(s)
1-Metil-4-fenilpiridinio/toxicidad , Catequina/metabolismo , Cobre/metabolismo , Zinc/metabolismo , Animales , Catequina/farmacología , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas WistarRESUMEN
The aim of this study was to determine the protective effect of quercetin, epigallocatechingallate, resveratrol, and rutin against the disruption of epithelial integrity induced by indomethacin in Caco-2 cell monolayers. Indomethacin decreased the transepithelial electrical resistance and increased the permeability of the monolayers to fluorescein-dextran. These alterations were abolished by all the tested polyphenols but rutin, with quercetin being the most efficient. The protective effect of quercetin was associated with its capacity to inhibit the redistribution of ZO-1 protein induced in the tight junction by indomethacin or rotenone, a mitochondrial complex-I inhibitor, and to prevent the decrease of ZO-1 and occludin expression induced by indomethacin. The fact that the antioxidant polyphenols assayed in this study differ in their protective capacity against the epithelial damage induced by indomethacin suggests that this damage is due to the ability of this agent to induce not only oxidative stress but also mitochondrial dysfunction.
Asunto(s)
Antiinflamatorios no Esteroideos/antagonistas & inhibidores , Antioxidantes/metabolismo , Enterocitos/metabolismo , Alimentos Funcionales/análisis , Indometacina/antagonistas & inhibidores , Ocludina/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Antiinflamatorios no Esteroideos/efectos adversos , Antioxidantes/análisis , Células CACO-2 , Catequina/análogos & derivados , Catequina/análisis , Catequina/metabolismo , Enterocitos/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Indometacina/efectos adversos , Ocludina/agonistas , Ocludina/antagonistas & inhibidores , Ocludina/genética , Permeabilidad/efectos de los fármacos , Polifenoles/análisis , Polifenoles/metabolismo , Transporte de Proteínas/efectos de los fármacos , Quercetina/análisis , Quercetina/metabolismo , Resveratrol , Estilbenos/análisis , Estilbenos/metabolismo , Uniones Estrechas/efectos de los fármacos , Proteína de la Zonula Occludens-1/agonistas , Proteína de la Zonula Occludens-1/antagonistas & inhibidores , Proteína de la Zonula Occludens-1/genéticaRESUMEN
Amyloid-beta is involved in neurodegeneration in Alzheimer's disease. The Amyloid-beta fraction 25-35 (Amyloid-beta 25-35) is believed to cause neurotoxicity through oxidative stress. We evaluated the antioxidant effects of Epicatechin on the Abeta25-35-caused hippocampal toxicity in vivo. Biochemical and histological evaluations, and learning and memory tasks, were assessed. Amyloid-beta 25-35 (100 microM/microL) or vehicle was injected into the CA1 hippocampal region of the rat 5 h after a single oral dose of Epicatechin (30 mg/kg). Lipid peroxidation and reactive oxygen species formation were measured in Amyloid-beta- and Amyloid-beta-Epicatechin-treated groups at 2 h and 24 h after dosing and formation of the lesion. There was an increase in lipid peroxidation and reactive oxygen species formation at 2-h and 24-h postlesion. Learning and memory tests were made 27-30 days after surgery in independent groups under the same experimental conditions. Immunohistochemical detection of glial-fibrilar acidic protein (GFAP) was evaluated in hippocampal tissues from the animals 30-days postsurgery. Amyloid-beta 25-35 caused a significant increase in lipid peroxidation and reactive oxygen species and a decrease in memory skills. In addition, hippocampal tissues from Amyloid-beta 25-35-treated animals showed an increased immunoreactivity against GFAP. In contrast, animals pretreated with Epicatechin had a significant decrease in lipid peroxidation and reactive oxygen species and an improvement in memory skills. GFAP immunoreactivity was also decreased. Our results showed that Amyloid-beta 25-35-caused oxidative damage of the hippocampus was blocked by the administration of Epicatechin.
Asunto(s)
Péptidos beta-Amiloides/toxicidad , Antioxidantes/farmacología , Catequina/farmacología , Hipocampo/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Animales , Antioxidantes/metabolismo , Catequina/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/metabolismo , Hipocampo/metabolismo , Inmunohistoquímica , Peroxidación de Lípido/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The nitric oxide-mediated actions are mostly due to cyclic GMP (cGMP) formation, but cGMP-independent mechanisms, such as tyrosine nitration, have been suggested as potential signaling pathways modulating the NO-induced responses. However, the mechanisms that lead to tyrosine nitration in platelets are poorly studied, and the protein targets of nitration have not been identified in these cells. Therefore, we have used the model of platelet adhesion to fibrinogen-coated plates to investigate the cGMP-independent mechanisms of the NO-donor sodium nitroprusside (SNP) that leads to inhibition of platelet adhesion. SNP concentration-dependently inhibited platelet adhesion, as observed at 15-min and 60-min adhesion. Additionally, SNP markedly increased the cGMP levels, and the soluble guanylate inhibitor ODQ nearly abolished the SNP-mediated cGMP elevations in all experimental conditions used. Nevertheless, ODQ failed to affect the adhesion inhibition obtained with 1.0 mM SNP at 15 min. On the other hand, superoxide dismutase or peroxynitrite (ONOO(-)) scavenger epigallocatechin gallate significantly reversed the inhibition of platelet adhesion by SNP (1 mM, 15 min). Western blot analysis in SNP (1 mM, 15 min)-treated platelets showed a single tyrosine-nitrated protein with an apparent mass of approximately 105 kDa. Nanospray LC-MS/MS identified the human alpha-actinin 1 cytoskeletal isoform (P12814) as the protein contained in the nitrated SDS gel band. Thus, tyrosine nitration of alpha-actinin, through ONOO(-) formation, may be a key modulatory mechanism to control platelet adhesion.