147 resultados para Resveratrol


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Tissue repair after replantation of avulsed teeth is directly related to the extent of damage to the cells of the periodontal ligament. Thus, immediate replantation is the treatment of choice for avulsed permanent teeth. To achieve more favorable prognostics, adequate storage media must be used to preserve periodontal ligament cells. A series of storage media are studied and show good results, such as saliva, milk, Hank's balanced solution (HBSS) and ViaSpan. However, recent studies were performed using news and promising storage media. Resveratrol has been extensively studied because of its antioxidant properties and its ability to prolong life of many organisms from yeast to mammals. One of its limitations is its poor solubility in aqueous vehicles. For this reason, the aim of this study was to evaluate the healing repair process after replantation of teeth of rats kept in Resveratrol using dimethyl sulfoxide (DMSO) as a vehicle. This study was approved by the Ethics Committee on Research with Animals, of the School of Dentistry of Araçatuba, Univ. Estadual Paulista, UNESP, Araçatuba, SP, Brazil. Were used 40 male rats, under general anesthesia upper right incisor were extracted and replanted. Treatments were done, dividing in four groups, of 10 animals each. In group I, the teeth were be extracted and immediately replanted into their sockets of origin (positive control). In group II, the teeth were immersed in 50 mL of resveratrol in DMSO (0.0512 g / ml) for 60 minutes. In group III teeth were kept for 60 minutes in 50 ml of DMSO. In group IV, the teeth were kept in dry for the same period (negative control). Then the teeth of animals in Groups II, III and IV were replanted in their sockets. Systemic antibiotics were administrated in all groups, and 60 days post-operative the animals were euthanized. The specimens were processed and stained in HE for histomorphological analysis. The results showed that resveratrol as storage media, was not able to improve the rep

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Background: Over 6 million people die annually in the world because of cancer. Several groups are focused on studying cancer chemoprevention approaches. Resveratrol, a polyphenol, at high dosages, has been reported as antitumor and chemopreventive. However, it has a dose-dependent effect on cell death, even on some cancer cells. Objectives: Our aim was to investigate this dose-dependent effect on human bladder carcinoma ECV304 cells during oxidative stress condition. Methods: For this purpose. ECV304 cells incubated with different Resveratrol concentrations were analyzed as for their metabolic rate, membrane permeability, DNA fragmentation, anti/proapoptotic protein levels and phosphatidylserine exposure after oxidative stress. Results: Resveratrol induced cell death at high concentrations (>20 mu M), but not at low ones (0.1-20 mu M). Pretreatment with 2.5 mu M protected the cells from oxidative damage, whereas 50 mu M intensified the cell death and significantly increased Bad/Bcl-2 ratio (proapoptotic/antiapoptotic proteins). Resveratrol was able to modulate NO and PGE(2) secretion and performed an anti-adhesion activity of neutrophils on PMA-activated ECV304 cells. Conclusions: Resveratrol at high doses induces cell death of ECV304 cells whereas low doses induce protection. Modulation of Bcl-2 protein induced by Resveratrol could be mediating this effect. This information about the role of Resveratrol on cancer alerts us about its dose-dependent effects and could lead the design of future chemoprevention strategies. Published by Elsevier Ireland Ltd.

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This study evaluated the antioxidant activity of five resveratrol analogs by relating the activity of the molecule with its chemical structure. The five resveratrol analogs were synthesized and the antioxidant activity was evaluated using the DPPH method. The resveratrol was used as the reference standard. A descriptive statistical analysis and ANOVA followed by the Tukey test, with the aid of software. The antioxidant activity of resveratrol analogs was considered statistically different, with the analog A which showed activity superior to the others. The five analogs presented lower antioxidant activity than the reference standard (p <0.001). According to the findings, hydroxylation was the molecular modification that gave the best evaluated antioxidant activity result. Resveratrol analogs may have an important antioxidative activity, but with the one with the higher IC50 was presented by the natural compound.

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Objective: To investigate, in male Wistar rats, the effects of long-term moderate red wine (RW) consumption (equivalent to similar to 0.15 mg% resveratrol RS), or RS in low (L, 0.15 mg%) or high (H, 400 mg%) doses in chow. Background: Both RW and RS exhibit cardioprotection. RS extends lifespan in obese rats. It is unclear whether RW consumption or low-dose RS delay vascular aging and prolong life span in the absence of overt risk factors. Methods: Endpoints were aerobic performance, exercise capacity, aging biomarkers (p53,p16,p21, telomere length and telomerase activity in aortic homogenates), vascular reactivity. Data were compared with controls (C) given regular chow. Results: Expressions of p53 decreased similar to 50% similar to with RW and LRS (p < 0.05 vs. C), p16 by similar to 29% with RW (p < 0.05 vs. C) and p21 was unaltered. RW and LRS increased telomere length >6.5-fold vs. C, and telomerase activity increased with LRS and HRS. All treatments increased aerobic capacity (C 32.5 +/- 1.2, RW 38.7 + 1.7, LRS 38.5 + 1.6, HRS 38.3 + 1.8 mlO2 min(-1) kg(-1)), and RW or LRS also improved time of exercise tolerance vs. C (p < 0.05). Endothelium-dependent relaxation improved with all treatments vs. C. Life span, however, was unaltered with each treatment vs. C = 673 +/- 30 days, p = NS. Conclusions: RW and LRS can preserve vascular function indexes in normal rats, although not extending life span. These effects were translated into better aerobic performance and exercise capacity. (c) 2012 Elsevier Ireland Ltd. All rights reserved.

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Oxidative DNA-Basenmodifikationen, wie 7,8-Dihydro-8-oxoguanin (8-oxoG), werden endogen in allen Zellen gebildet. Die beobachtbaren Spiegel ergeben sich aus dem Gleichgewicht zwischen der Bildung durch reaktive Sauerstoffspezies (ROS), sowie der gleichzeitigen Reparatur der DNA-Schäden. Durch ihr hohes mutagenes Potential, tragen oxidative DNA-Basenmodifikationen zur spontanen Mutationsrate bei. Der Ausfall wichtiger DNA-Reparaturmechanismen führt in Ogg1(-/-)Csb(-/-)-Knockout-Mäusen zu einem Anstieg von 8 oxoG und der spontanen Mutationsrate.rnIn dieser Arbeit sollte untersucht werden, ob die basalen Spiegel an oxidativen Basenmodifikationen und die spontanen Mutationsraten in vivo durch die orale Gabe von Resveratrol moduliert werden können. Resveratrol ist ein Pflanzeninhaltsstoff (u.a. aus Rotwein) mit einer Vielzahl von Wirkungen, der bereits in zahlreichen Studien ein chemopräventives Potential gezeigt hat und antioxidativ wirkt.rnAn verschiedenen Mausgenotypen wurden zum einen eine Kurzzeit-Behandlung (7 Tage mit 100 mg/kg per Gavage) und zum anderen eine Langzeit-Behandlung (3-9 Monate mit 0,04% ad libitum) mit Resveratrol durchgeführt. Die oxidativen DNA Schäden wurden in primären Maushepatozyten mit Hilfe einer modifizierten Alkalischen Elution, mit der bakteriellen Formamidopyrimidin-DNA Glykosylase als Sonde, bestimmt. Zur Analyse der Mutationsrate wurde der BigBlue® Mutationsassay mit anschließender Sequenzierung der Mutationen verwendet.rnDie Ergebnisse zeigen, dass die Kurzzeit- und die Langzeit-Behandlung mit Resveratrol die basalen Spiegel oxidativer DNA-Basenmodifikationen senken. Die Reduktion ist jeweils wesentlich ausgeprägter in den reparaturdefizienten Ogg1(-/-)Csb(-/-)-Mäusen zu erkennen. Auch die spontane Mutationsrate wird durch eine mehrmonatige Behandlung mit Resveratrol um ungefähr 20-30% reduziert.rnAnschließende mechanistische Untersuchungen zeigten, dass dieser Schutz wahrscheinlich auf einer Induktion der antioxidativen Schutzmechanismen begründet ist. So wurde gefunden, dass primäre Hepatozyten aus mit Resveratrol behandelten Mäusen wesentlich besser gegen exogen herbeigeführten oxidativen Stress geschützt sind, als Hepatozyten von unbehandelten Tieren. Ein weiterer Hinweis ist die Hochregulation der mRNA-Spiegel von verschiedenen antioxidativen Schutzenzymen, wie Superoxiddismutase 1 / 2, Hämoxygenase 1, Glutathionperoxidase 1, nach der Gabe von Resveratrol in Mäuselebern. Außerdem sind die oxidativen Markermutationen (GC->TA-Transversionen) stärker von der Reduktion der spontanen Mutationsrate betroffen, als andere Mutationen (z.B. GC->AT-Transitionen).rnDie Ergebnisse zeigen erstmalig, dass spontane Mutationen in vivo durch Fremdstoffe in der Nahrung reduziert werden können. Im Falle von Resveratrol wird diese Reduktion wahrscheinlich durch eine Stimulation der antioxidativen Schutzmechanismen ausgelöst.rn

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Die Pathogenese chronisch inflammatorischer Erkrankungen ist von einer Dysregulation der pro-inflammatorischen Genexpression geprägt. Dieser liegen wahrscheinlich pathologische Veränderungen der Aktivität von verschiedenen Transkriptionsfaktoren und RNA-bindenden Proteinen zugrunde. In dieser Arbeit konnte die Regulation der KSRP-Expression in einem murinen Modell der rheumatoiden Arthritis (RA) nachgewiesen werden. In humanen Chondrozyten führte eine erhöhte KSRP-Expression zu einer Reduktion der Expression von bekannten KSRP-Zielgenen. Der Vergleich von verschiedenden Microarray-Analysen aus den verwendeten humanen und murinen Modellen der RA führte zur Identifikation von pro-inflammatorischen und pro-angiogenetischen Faktoren (SPARC, MMP2, MMP3, PLA2G2D, GZMA, HPSE, TNMD und IL-18-R), die in der RA eine Rolle spielen und höchstwahrscheinlich durch eine erhöhte KSRP-Expression reguliert werden. Daher könnte eine Modulation der KSRP-Expression bei der Therapie von Autoimmunerkrankungen von Bedeutung sein. In diesem Zusammenhang ist die Detektion der Bindung des cardioprotektiven und anti-inflammatorisch wirkenden Naturstoffs Resveratrol an KSRP zu nennen. Diese spezifische Interaktion führte zu einer Reduktion der p38-MAPK-vermittelten Thr-Phosphorylierung des KSRP-Proteins (in situ und in vivo), was eine Aktivierung der KSRP-vermittelten Mechanismen zur Folge hatte. Somit konnte in situ die mRNA-Stabilität der iNOS reduziert und die miR-155-Expression erhöht werden. Im murinen Atherosklerosemodell führte die Behandlung mit Resveratrol zu einer verringerten Expression bekannter KSRP-Ziel-mRNAs. rnNeben diesem post-translationalen Regulationsmechanismus von KSRP durch Resveratrol konnte die Modulation der KSRP-Expression auf transkriptioneller Ebene durch KSRP selbst gezeigt werden. Dies geschieht möglicherweise über die Bindung von KSRP an das FUSE-analoge Element innerhalb des KSRP-Promotors, welches eine positive Autoregulation der KSRP-Expression bewirkt. Bei der Analyse der post-transkriptionellen Regulation der KSRP-Expression interagierten die mRNA-bindenden Proteine HuR, PABP und die AUF-1-Isoformen p40, p42 und p45 in vitro mit der KSRP-3’UTR. Dabei konnte in Expressionsanalysen nachgewiesen werden, dass die KSRP-mRNA durch PABP positiv und durch p42 negativ reguliert wird.rnZusammenfassend ist zu sagen, dass die KSRP-Expression neben post-translationalen Mechanismen auch auf transkriptioneller und post-transkriptioneller Ebene moduliert wird. Zusätzlich wurde eine Regulation der KSRP-Expression innerhalb entzündlicher Erkrankungen nachgewiesen, die Bedeutung dieser Modulation für die pro-inflammatorischen Genexpression diskutiert und ein möglicher therapeutischer Angriffspunkt durch Resveratrol identifiziert.

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Background: Among grape skin polyphenols, trans-resveratrol (RES) has been reported to slow the development of cardiac fibrosis and to affect myofibroblast (MFB) differentiation. Because MFBs induce slow conduction and ectopic activity following heterocellular gap junctional coupling to cardiomyocytes, we investigated whether RES and its main metabolites affect arrhythmogenic cardiomyocyte-MFB interactions. Methods: Experiments were performed with patterned growth strands of neonatal rat ventricular cardiomyocytes coated with cardiac MFBs. Impulse propagation characteristics were measured optically using voltage-sensitive dyes. Long-term video recordings served to characterize drug-related effects on ectopic activity. Data are given as means ± S.D. (n = 4–20). Results: Exposure of pure cardiomyocyte strands to RES at concentrations up to 10 µmol/L had no significant effects on impulse conduction velocity (θ) and maximal action potential upstroke velocities (dV/dtmax). By contrast, in MFB-coated strands exhibiting slow conduction, RES enhanced θ with an EC50 of ~10 nmol/L from 226 ± 38 to 344 ± 24 mm/s and dV/dtmax from 48 ± 7 to 69 ± 2%APA/ms, i.e., to values of pure cardiomyocyte strands (347 ± 33 mm/s; 75 ± 4%APA/ms). Moreover, RES led to a reduction of ectopic activity over the course of several hours in heterocellular preparations. RES is metabolized quickly in the body; therefore, we tested the main known metabolites for functional effects and found them similarly effective in normalizing conduction with EC50s of ~10 nmol/L (3-OH-RES), ~20 nmol/L (RES-3-O-β-glucuronide) and ~10 nmol/L (RES-sulfate), respectively. At these concentrations, neither RES nor its metabolites had any effects on MFB morphology and α-smooth muscle actin expression. This suggests that the antiarrhythmic effects observed were based on mechanisms different from a change in MFB phenotype. Conclusions: The results demonstrate that RES counteracts MFB-dependent arrhythmogenic slow conduction and ectopic activity at physiologically relevant concentrations. Because RES is rapidly metabolized following intestinal absorption, the finding of equal antiarrhythmic effectiveness of the main RES metabolites warrants their inclusion in future studies of potentially beneficial effects of these substances on the heart.