stilbenes and caffeic-acid
stilbenes has been researched along with caffeic-acid* in 26 studies
Reviews
1 review(s) available for stilbenes and caffeic-acid
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Natural and synthetic α,β-unsaturated carbonyls for NF-κB inhibition.
The nuclear transcription factor NF-κB has gained considerable importance due to its major involvement in inflammation and constitutive activity in malignant cells. It is induced by a variety of stimuli and controls the expression of several proteins involved in biological processes. Numerous natural products and synthesized organic molecules have been reported to inhibit NF-κB and have played an integral role in identifying implicated pathways. Prominent among them are the sesquiterpene lactones, polyphenolic enones and other α,β-unsaturated carbonyl-containing molecules, particularly α-methylene-γ-butyrolactones.. This mini-review provides an introductory overview of some of the associated pathways involving NF-κB in cancer and discusses the structures and mode of action of natural α,β-unsaturated carbonyl-containing inhibitors and their synthetic counterparts. A review of the recent methods for the synthesis of α-alkylidene-γ-butyrolactones is also provided, with the aim of arousing the interest of synthetic chemists for the design and development of novel NF-κB inhibitors.. Modulating damaging effects without harming the inflammatory and immune responses are crucial parameters for developing NF-κB inhibitors. Examination of novel α,β-unsaturated carbonyls and the further discovery of simple methods to prepare such molecules should lead to the identification of site-specific inhibitors. Topics: Caffeic Acids; Flavonoids; NF-kappa B; Quinones; Sesquiterpenes; Stilbenes | 2009 |
Other Studies
25 other study(ies) available for stilbenes and caffeic-acid
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Stilbene content and expression of stilbene synthase genes in cell cultures of Vitis amurensis treated with cinnamic and caffeic acids.
It has previously been shown that exogenous application of p-coumaric acid (CA), a precursor of phenolic compounds, improved stilbene production in cell cultures of Vitis amurensis. This study examines the effect of cinnamic (Cin) and caffeic (Caf) acids, which are also phenolic precursors, on stilbene biosynthesis in the cell cultures. Five stilbenes, t-resveratrol diglucoside, t-piceid (t-resveratrol glucoside), t-resveratrol, t-ε-viniferin, and t-δ-viniferin, were found in the treated and untreated cells. Cin acid increased the total stilbene production in the grape cell cultures 2.3-3.5 times in comparison with that in the untreated cells. Caf acid increased the total stilbene production by 1.8- to 1.9-fold, but this increase was not considerably different from stilbene production in the untreated cells. Cin acid affected the total stilbene production via a marked increase in the content of t-resveratrol diglucoside (up to 2.2 times), t-piceid (up to three times), t-resveratrol (up to 5.1 times), t-ε-viniferin (up to eight times), and t-δ-viniferin (up to 9.2 times). Transcription levels of VaSTS5, 6, 7, 8, and 10 genes considerably increased under 0.1, 0.25, and 0.5 mM Cin acid. These results indicate that Cin acid increased stilbene production in V. amurensis calli via a selective enhancement of STS gene expression. Topics: Acyltransferases; Caffeic Acids; Cell Culture Techniques; Cinnamates; Gene Expression Regulation, Plant; Plant Proteins; Stilbenes; Vitis | 2018 |
Improved chemical stability and cellular antioxidant activity of resveratrol in zein nanoparticle with bovine serum albumin-caffeic acid conjugate.
In this study, bovine serum albumin (BSA)-caffeic acid (CA) conjugate was prepared with free radical-induced grafting method. The CA to BSA ratio of the conjugate was 115.7 mg/g. In vitro antioxidant activity assays suggested that BSA-CA conjugates had stronger antioxidant activity than BSA. Resveratrol-loaded zein encapsulated with BSA and BSA-CA conjugate core-shell nanoparticles were prepared with antisolvent method. Particle sizes were 206.3 nm, and 217.2 nm for BSA and BSA-CA, respectively. The encapsulation efficiencies (EEs) were 85.3% and 86.5% for zein-BSA and zein-BSA-CA nanoparticles, respectively. SEM results indicated that both nanoparticles were spherical with mean diameter approximately 200 nm and smooth surfaces. Both thermal and UV light stability of resveratrol was significantly improved after nanoencapsulation. BSA-CA conjugate showed remarkably greater protection than BSA against resveratrol degradation. Cellular antioxidant activity (CAA) study confirmed that resveratrol in both zein-BSA and zein-BSA-CA nanoparticles had significant higher antioxidant activities than resveratrol alone. Topics: Antioxidants; Caffeic Acids; Drug Stability; Nanoparticles; Particle Size; Resveratrol; Serum Albumin, Bovine; Stilbenes; Zein | 2018 |
Development and validation of a simple high performance thin layer chromatography method combined with direct 1,1-diphenyl-2-picrylhydrazyl assay to quantify free radical scavenging activity in wine.
The aim of this study was to: (a) develop a simple, high performance thin layer chromatographic (HPTLC) method combined with direct 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay to rapidly assess and compare free radical scavenging activity or anti-oxidant activity for major classes of polyphenolics present in wines; and (b) to investigate relationship between free radical scavenging activity to the total polyphenolic content (TPC) and total antioxidant capacity (TAC) in the wine samples. The most potent free radical scavengers that we tested for in the wine samples were found to be resveratrol (polyphenolic non-flavonoid) and rutin (flavonoid), while polyphenolic acids (caffeic acid and gallic acid) although present in all wine samples were found to be less potent free radical scavengers. Therefore, the total antioxidant capacity was mostly affected by the presence of resveratrol and rutin, while total polyphenolic content was mostly influenced by the presence of the less potent free radical scavengers gallic and caffeic acids. Topics: Antioxidants; Biphenyl Compounds; Caffeic Acids; Chromatography, Thin Layer; Free Radical Scavengers; Gallic Acid; Picrates; Polyphenols; Reproducibility of Results; Resveratrol; Rutin; Stilbenes; Wine | 2016 |
Dietary Phenolic Compounds Interfere with the Fate of Hydrogen Peroxide in Human Adipose Tissue but Do Not Directly Inhibit Primary Amine Oxidase Activity.
Resveratrol has been reported to inhibit monoamine oxidases (MAO). Many substrates or inhibitors of neuronal MAO interact also with other amine oxidases (AO) in peripheral organs, such as semicarbazide-sensitive AO (SSAO), known as primary amine oxidase, absent in neurones, but abundant in adipocytes. We asked whether phenolic compounds (resveratrol, pterostilbene, quercetin, and caffeic acid) behave as MAO and SSAO inhibitors. AO activity was determined in human adipose tissue. Computational docking and glucose uptake assays were performed in 3D models of human AO proteins and in adipocytes, respectively. Phenolic compounds fully inhibited the fluorescent detection of H2O2 generated during MAO and SSAO activation by tyramine and benzylamine. They also quenched H2O2-induced fluorescence in absence of biological material and were unable to abolish the oxidation of radiolabelled tyramine and benzylamine. Thus, phenolic compounds hampered H2O2 detection but did not block AO activity. Only resveratrol and quercetin partially impaired MAO-dependent [(14)C]-tyramine oxidation and behaved as MAO inhibitors. Phenolic compounds counteracted the H2O2-dependent benzylamine-stimulated glucose transport. This indicates that various phenolic compounds block downstream effects of H2O2 produced by biogenic or exogenous amine oxidation without directly inhibiting AO. Phenolic compounds remain of interest regarding their capacity to limit oxidative stress rather than inhibiting AO. Topics: Adipocytes; Adipose Tissue; Adolescent; Adult; Aged; Amine Oxidase (Copper-Containing); Anti-Inflammatory Agents; Antioxidants; Benzylamines; Caffeic Acids; Diet; Female; Fluorometry; Hexoses; Humans; Hydrogen Peroxide; Inflammation; Middle Aged; Molecular Docking Simulation; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Oxidative Stress; Oxygen; Phenols; Quercetin; Resveratrol; Stilbenes; Tyramine; Young Adult | 2016 |
Riboflavin Phototransformation on the Changes of Antioxidant Capacities in Phenolic Compounds.
Eight phenolic compounds including: p-coumaric acid, vanillic acid, caffeic acid, chlorogenic acid, trolox, quercetin, curcumin, and resveratrol were treated with riboflavin (RF) photosensitization and in vitro antioxidant capacities of the mixtures were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2' azino bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Mixtures containing p-coumaric acid and vanillic acid under RF photosensitization showed increases in ferric ion reducing ability and radical scavenging activity of DPPH, whereas mixtures of other compounds had decreases in both radical scavenging ability and ferric reducing antioxidant power. Hydroxycoumaric acid and conjugated hydroxycoumaric and coumaric acids were tentatively identified from RF photosensitized p-coumaric acid, whereas dimmers of vanillic acid were tentatively identified from RF photosensitized vanillic acid. RF photosensitization may be a useful method to enhance antioxidant properties like ferric ion reducing abilities of some selected phenolic compounds. Topics: Antioxidants; Benzothiazoles; Biphenyl Compounds; Caffeic Acids; Chlorogenic Acid; Chromans; Coumaric Acids; Curcumin; Light; Molecular Structure; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Propionates; Quercetin; Resveratrol; Riboflavin; Stilbenes; Sulfonic Acids; Vanillic Acid | 2016 |
Plausible anti-inflammatory mechanism of resveratrol and caffeic acid against chronic stress-induced insulin resistance in mice.
Stress is associated with many diseases and dysfunctions, such as depression, cardiovascular alterations, immunological function disorder, inflammation, obesity, and insulin resistance. Stress-induced inflammation is associated with the genesis of insulin resistance. Stress activates hypothalamic pituitary adrenal axis, Renin Angiotensin System pathway, and sympatho-adrenal system, all of which are involved in the production of cytokines, causing the negative downregulation of insulin signaling either by phosphorylating serine residues of IRS or by inhibiting the activity of Akt leading to insulin resistance. In this study, male LACA mice (20-30 g) were subjected to 2 h of chronic restraint stress daily for 30 days at variable time. Resveratrol, caffeic acid, glibenclamide, and their combinations were administered 45 min prior to restraint stress daily for 30 days and their anti-inflammatory effect was examined on CRS-induced behavioral, biochemical, and metabolic alterations. Induction of stress in mice was evident by increased corticosterone and decreased bodyweight. Chronic restraint stress for 30 days developed insulin resistance characterized by hyperglycemia, hyperinsulinemia, increased glycosylated haemoglobin (HbA1c), and homeostasis model assessment of insulin resistance index, hyperlipidemia, increased inflammatory cytokines, and TNF-α. Treatment with resveratrol, caffeic acid, and their combinations has attenuated stress-induced insulin resistance by reducing inflammation. Topics: Animals; Anti-Inflammatory Agents; Blood Glucose; Caffeic Acids; Corticosterone; Cytokines; Drug Therapy, Combination; Glyburide; Hypoglycemic Agents; Insulin Resistance; Male; Mice, Inbred Strains; Restraint, Physical; Resveratrol; Stilbenes; Stress, Psychological | 2016 |
Discovery of oral-available resveratrol-caffeic acid based hybrids inhibiting acetylated and phosphorylated STAT3 protein.
Constitutive activation of STAT3 has been found in a wide variety of cancers and demonstrated as a very attractive therapeutic target. Disrupting both acetylation and phosphorylation of STAT3 protein was hypothesized to greatly deactivate STAT3, therefore, treating cancers. To demonstrate the hypothesis, two series of novel resveratrol-caffeic acid hybrids were designed aiming to regulate both acetylation and phosphorylation of STAT3 protein, which is also the first report of the synthetic inhibitors simultaneously regulating two biological reactions of STAT3 to our knowledge. Most of these compounds were demonstrated with preferential antitumor activity with low IC Topics: Acetylation; Administration, Oral; Antineoplastic Agents; Apoptosis; Biological Availability; Caffeic Acids; Cell Line, Tumor; Cell Proliferation; Gene Expression Regulation, Neoplastic; Humans; Lysine; Molecular Docking Simulation; Molecular Targeted Therapy; Phosphorylation; Protein Conformation; Resveratrol; STAT3 Transcription Factor; Stilbenes | 2016 |
Analysis of phenolics in wine by high performance thin-layer chromatography with gradient elution and high resolution plate imaging.
Health benefits of wine, especially with red wine, have been linked to the presence of a wide range of phenolic antioxidants. Thus, the aim of this study was to develop a simple, high performance thin layer chromatographic (HPTLC) method combined with high resolution digital plate images to visually compare multiple wine samples simultaneously on a single chromatographic plate and to quantify levels of gallic acid, caffeic acid, resveratrol and rutin, as representatives of the four different classes of phenolics found in wines. We also wanted to investigate the contribution of the investigated phenolic compounds to the total polyphenolic content (TPC) and total antioxidant capacity (TAC) of the wine samples. The average concentrations of caffeic acid, gallic acid, resveratrol, and rutin in the red wines were 2.15, 30.17, 0.59 and 2.47 mg/L respectively with their concentration below limit of quantification in the white wine samples. The highest concentration of resveratrol and rutin is found in the Cabernet and Shiraz wine samples. The amounts of gallic acid are correlated with TPC (r=0.58). Italian wines have the highest correlation between TPC and TAC (r=0.99) although they do not contain detectable amounts of resveratrol, they contain significant amount of rutin. Therefore, antioxidant properties might be associated with the presence of flavanols in these wines. Topics: Antioxidants; Caffeic Acids; Chromatography, Thin Layer; Gallic Acid; Phenols; Resveratrol; Rutin; Stilbenes; Wine | 2015 |
Phenolic compounds, organic acids and antioxidant activity of grape juices produced in industrial scale by different processes of maceration.
The effect of maceration process on the profile of phenolic compounds, organic acids composition and antioxidant activity of grape juices from new varieties of Vitis labrusca L. obtained in industrial scale was investigated. The extraction process presented a high yield without pressing the grapes. The use of a commercial pectinase resulted in an increase on extraction yield and procyanidins B1 and B2 concentrations and a decrease on turbidity and concentration of catechins. The combination of 60 °C and 3.0 mL 100 kg(-1) of enzyme resulted in the highest extraction of phenolic compounds, reducing the content of acetic acid. The juices presented high antioxidant activity, related to the great concentration of malvidin, cyanidin, catechin and caffeic, cinnamic and gallic acids. Among the bioactive compounds, the juices presented high concentration of procyanidin B1, caffeic acid and trans-resveratrol, with higher levels compared to those reported in the literature. Topics: Anthocyanins; Antioxidants; Biflavonoids; Caffeic Acids; Catechin; Cinnamates; Food Handling; Fruit and Vegetable Juices; Gallic Acid; Phenols; Polygalacturonase; Principal Component Analysis; Proanthocyanidins; Resveratrol; Stilbenes; Temperature; Vitis | 2015 |
Phenolic composition and antioxidant activity in sparkling wines: modulation by the ageing on lees.
Sparkling wines (SW) have a special biological ageing on lees that is performed using two distinct methods: in the bottle (Champenoise) or in isobaric tanks (Charmat method). The objective of this study was to compare the levels of phenolic compounds, β-Glucosidase and antioxidant activity during the ageing on lees, in samples of SW produced at industrial scale by both methods. The β-Glucosidase activity has been constant over time, showing a close relationship with all the polyphenols studied (resveratrol, piceid, tyrosol, gallic, caffeic and ferulic acids), which were affected by the sur lie time. With these cross-reactions, the biological properties of the SW were also modulated. The results showed that the long period of ageing decreased the antioxidant potential in all samples. This work demonstrates that the sur lie is more important than the production method itself, due to its ability to modulate the necessary changes to achieve the specific objective. Topics: Antioxidants; beta-Glucosidase; Caffeic Acids; Coumaric Acids; Food Handling; Gallic Acid; Glucosides; Phenylethyl Alcohol; Polyphenols; Resveratrol; Stilbenes; Wine | 2014 |
Synergistic effects of polyphenols and methylxanthines with Leucine on AMPK/Sirtuin-mediated metabolism in muscle cells and adipocytes.
The AMPK-Sirt1 pathway is an important regulator of energy metabolism and therefore a potential target for prevention and therapy of metabolic diseases. We recently demonstrated leucine and its metabolite β-hydroxy-β-methylbutyrate (HMB) to synergize with low-dose resveratrol (200 nM) to activate sirtuin signaling and stimulate energy metabolism. Here we show that leucine exerts a direct effect on Sirt1 kinetics, reducing its Km for NAD(+) by >50% and enabling low doses of resveratrol to further activate the enzyme (p = 0.012). To test which structure elements of resveratrol are necessary for synergy, we assessed potential synergy of structurally similar and dissimilar polyphenols as well as other compounds converging on the same pathways with leucine using fatty acid oxidation (FAO) as screening tool. Dose-response curves for FAO were constructed and the highest non-effective dose (typically 1-10 nM) was used with either leucine (0.5 mM) or HMB (5 µM) to treat adipocytes and myotubes for 24 h. Significant synergy was detected for stilbenes with FAO increase in adipocytes by 60-70% (p<0.05) and in myotubes >2000% (p<0.01). Sirt1 and AMPK activities were stimulated by ∼65% (p<0.001) and ∼50% (p<0.03), respectively. Similarly, hydroxycinnamic acids and derivatives (chlorogenic, cinnamic, and ferulic acids) combined with leucine/HMB increased FAO (300-1300%, p<0.01), AMPK activity (50-150%, p<0.01), and Sirt1 activity (∼70%, p<0.001). In contrast, more complex polyphenol structures, such as ellagic acid and epigallocatechin gallate required higher concentrations (>1 µM) and exhibited little or no synergy. Thus, the six-carbon ring structure bound to a carboxylic group seems to be a necessary element for leucine/HMB synergy with other stilbenes and hydroxycinnamic acids to stimulate AMPK/Sirt1 dependent FAO; these effects occur at concentrations that produce no independent effects and are readily achievable via oral administration. Topics: 3T3-L1 Cells; Adipocytes; AMP-Activated Protein Kinases; Animals; Caffeic Acids; Chlorogenic Acid; Ellagic Acid; Fatty Acids; Humans; Leucine; Mice; Muscle Cells; NAD; Oxidation-Reduction; Phosphodiesterase Inhibitors; Polyphenols; Protein Kinase Inhibitors; Resveratrol; Sirtuin 1; Stilbenes; Valerates; Xanthines | 2014 |
A common fungal associate of the spruce bark beetle metabolizes the stilbene defenses of Norway spruce.
Norway spruce (Picea abies) forests suffer periodic fatal attacks by the bark beetle Ips typographus and its fungal associate, Ceratocystis polonica. Norway spruce protects itself against fungal and bark beetle invasion by the production of terpenoid resins, but it is unclear whether resins or other defenses are effective against the fungus. We investigated stilbenes, a group of phenolic compounds found in Norway spruce bark with a diaryl-ethene skeleton with known antifungal properties. During C. polonica infection, stilbene biosynthesis was up-regulated, as evidenced by elevated transcript levels of stilbene synthase genes. However, stilbene concentrations actually declined during infection, and this was due to fungal metabolism. C. polonica converted stilbenes to ring-opened, deglycosylated, and dimeric products. Chromatographic separation of C. polonica protein extracts confirmed that these metabolites arose from specific fungal enzyme activities. Comparison of C. polonica strains showed that rapid conversion of host phenolics is associated with higher virulence. C. polonica is so well adapted to its host's chemical defenses that it is even able to use host phenolic compounds as its sole carbon source. Topics: Acyltransferases; Adaptation, Physiological; Animals; Ascomycota; Caffeic Acids; Carbon; Coleoptera; Glucosides; Host-Pathogen Interactions; Picea; Plant Bark; Plant Diseases; Stilbenes | 2013 |
Moderate red wine and grape juice consumption modulates the hydrolysis of the adenine nucleotides and decreases platelet aggregation in streptozotocin-induced diabetic rats.
This study investigated the ex vivo effects of the moderate red wine (RW) and grape juice (GJ) consumption, and the in vitro effects of the resveratrol, caffeic acid, gallic acid, quercetin, and rutin on NTPDase (nucleoside triphosphate diphosphohydrolase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), 5'-nucleotidase, and adenosine deaminase (ADA) activities in platelets and platelet aggregation from streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 10): control/saline, control/GJ, control/RW, diabetic/saline, diabetic/GJ, and diabetic/RW. RW and GJ were administered for 45 days; after this period, the blood was collected for experimental determinations. Results showed that NTPDase, E-NPP, 5'-nucleotidase, and ADA activities as well as platelet aggregation were increased in the diabetic/saline group compared to the control/saline group. Treatment with RW and GJ increased ectonucleotidases activities and prevented the increase in the ADA activity in the diabetic/GJ and diabetic/RW groups. Platelet aggregation was also decreased by the treatment with RW and GJ in the diabetic/GJ and diabetic/RW groups. In the in vitro tests, resveratrol, caffeic acid, and gallic acid increased ATP, ADP, and AMP hydrolysis, while quercetin and rutin decreased the hydrolysis of these nucleotides in platelets of diabetic rats. The ADA activity and platelet aggregation were reduced in platelets of diabetic rats in the presence of all polyphenols tested in vitro. These findings suggest that RW, GJ, and all polyphenols tested were able to modulate the ectoenzymes activities. Moreover, a decrease in the platelet aggregation was observed and it could contribute to the prevention of platelet abnormality, and consequently vascular complications in diabetic state. Topics: 5'-Nucleotidase; Adenine Nucleotides; Adenosine Deaminase; Animals; Antioxidants; Beverages; Blood Platelets; Caffeic Acids; Diabetes Mellitus, Experimental; Dose-Response Relationship, Drug; Hydrolysis; Male; Plant Preparations; Platelet Aggregation; Pyrophosphatases; Quercetin; Rats; Rats, Wistar; Resveratrol; Rutin; Stilbenes; Vitis; Wine | 2013 |
Amyloid aggregation of lysozyme: the synergy study of red wine polyphenols.
The amyloidoses are diseases associated with nonnative folding of proteins and characterized by the presence of protein amyloid aggregates. The ability of quercetin, resveratrol, caffeic acid, and their equimolar mixtures to affect amyloid aggregation of hen egg white lysozyme in vitro was detected by Thioflavin T fluorescence assay. The anti-amyloid activities of tested polyphenols were evaluated by the median depolymerization concentrations DC50 and median inhibition concentrations IC50 . Single substances are more efficient (by at least one order) in the depolymerization of amyloid aggregates assay than in the inhibition of the amyloid formation with IC50 in 10(-4) to 10(-5) M range. Analyzed mixture samples showed synergic or antagonistic effects in both assays. DC50 values ranged from 10(-5) to 10(-8) M and IC50 from 10(-5) to 10(-9) M, respectively. We observed that certain mixtures of studied polyphenols can synergistically inhibit production of amyloids aggregates and are also effective in depolymerization of the aggregates. Synergic or antagonistic effects of studied mixtures were correlated with protein-small ligand docking studies and AFM results. Differences in these activities could be explained by binding of each polyphenol to a different amino acid sequence within the protein. Our results indicate that synergic/antagonistic anti-amyloid effects of studied mixtures depend on the selective binding of polyphenols to the known amyloidogenic sequences in the lysozyme chain. Our findings of the effective reduction of amyloid aggregation of lysozyme by polyphenol mixtures in vitro are of the utter physiological relevance considering the bioavailability and low toxicity of tested phenols. Topics: Amyloid; Animals; Antioxidants; Caffeic Acids; Chickens; Models, Molecular; Muramidase; Polyphenols; Quercetin; Resveratrol; Stilbenes; Wine | 2013 |
Natural polyphenols may ameliorate damage induced by copper overload.
The effect of the simultaneous exposure to transition metals and natural antioxidants frequently present in food is a question that needs further investigation. We aimed to explore the possible use of the natural polyphenols caffeic acid (CA), resveratrol (RES) and curcumin (CUR) to prevent damages induced by copper-overload on cellular molecules in HepG2 and A-549 human cells in culture. Exposure to 100μM/24h copper (Cu) caused extensive pro-oxidative damage evidenced by increased TBARS, protein carbonyls and nitrite productions in both cell types. Damage was aggravated by simultaneous incubation with 100μM of CA or RES, and it was also reflected in a decrease on cellular viability explored by trypan blue dye exclusion test and LDH leakage. Co-incubation with CUR produced opposite effects demonstrating a protective action which restored the level of biomarkers and cellular viability almost to control values. Thus, while CA and RES might aggravate the oxidative/nitrative damage of Cu, CUR should be considered as a putative protective agent. These results could stimulate further research on the possible use of natural polyphenols as neutralizing substances against the transition metal over-exposure in specific populations such as professional agrochemical sprayers and women using Cu-intrauterine devices. Topics: Antioxidants; Caffeic Acids; Cell Line, Tumor; Copper; Curcumin; Enzyme Inhibitors; Humans; Polyphenols; Resveratrol; Stilbenes | 2012 |
In vitro antioxidant activities of three red wine polyphenols and their mixtures: an interaction study.
The well-known antioxidant activity of red wine is explained mostly by its polyphenols content, where the final effect is based on the wine components' interaction. The aim of our work was the study of the interaction of three red wine polyphenols--quercetin, resveratrol and caffeic acid--alone and in their equimolar binary and ternary mixtures in different antioxidant/scavenging assays (inhibition of 2-deoxy-D-ribose degradation by hydroxyl radical, FRAP, Fe(III) reducing power, DPPH, ABTS and NO scavenging, respectively). Interaction analysis, based on median effect equation, was performed for the determination of synergy and/or antagonism. The obtained results indicate that the mutual interactions of tested polyphenols in their mixtures are markedly different from each other, depending on the reaction mechanism of the assay used. The measured antioxidant activity of individual polyphenols is not a constant value when other substances are present in the mixture with this polyphenol. Interactions can cause the finally observed synergy/antagonism/additive effects without any possibility of predicting them from the known activities of single compounds. This “unpredictability” claim based on in vitro assay results should be very important in multiple systems and processes in Nature, where the interactions among compounds in mixtures need to be take into account. Topics: Antioxidants; Caffeic Acids; Deoxyribose; Ferric Compounds; Oxidation-Reduction; Polyphenols; Quercetin; Resveratrol; Stilbenes; Wine | 2012 |
Bioconversion of grape and chokeberry wine polyphenols during simulated gastrointestinal in vitro digestion.
The primary objective of the present study was to assess the qualitative and quantitative changes of wine polyphenols during in vitro digestion process conducted in a gastrointestinal tract model. Wines selected for these experiments were red grape, white grape and chokeberry wines. Following the stages of in vitro digestion-stomach, small and large intestine-qualitative and quantitative changes particularly in phenolic acids were monitored. Decomposition of resveratrol and chlorogenic acid, secretion of caffeic acid and formation of other derivatives characterized with high antioxidant activity were determined. As a second focus of this work the evaluation of interactions between human fecal microflora (Enterobacteriaceae, Lactobacillus, Enterococcus and Bifidobacterium) and polyphenolic compounds and their derivatives secreted during the digestion were performed. Topics: Antioxidants; Bacteria; Caffeic Acids; Chlorogenic Acid; Feces; Flavonoids; Gastrointestinal Tract; Humans; Models, Biological; Phenols; Photinia; Plant Extracts; Polyphenols; Resveratrol; Stilbenes; Vitis; Wine | 2011 |
Profiling of resveratrol oligomers, important stress metabolites, accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola.
In the Vitaceae, viniferins represent a relatively restricted group of trans-resveratrol oligomers with antifungal properties, thus enabling plants to cope with pathogen attack. The aim of this study was to perform isolation and structural characterization of the whole class of viniferins accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola . Infected leaves of resistant plants were collected 6 days after infection, extracted with methanol, and prepurified by flash chromatography using ENV+ and Toyopearl HW 40S resins. Further fractionation using normal-phase preparative chromatography and then reversed-phase preparative chromatography allowed isolation of 14 peaks. The isolated compounds were identified using advanced mass spectrometry techniques and extensive one- and two-dimensional nuclear magnetic resonance measurements, UV, CD, optical properties, and molecular mechanic calculations. The results demonstrated the presence in infected leaves of seven dimers (six stilbenes and one stilbenoid), of which four were new in grapevine (ampelopsin D, quadrangularin A, E-ω-viniferin, and Z-ω-viniferin), four trimers (three stilbenes and one stilbenoid), of which two (Z-miyabenol C and E-cis-miyabenol C) were new in grapevine, three tetramer stilbenoids, all new in grapevine, isohopeaphenol, ampelopsin H, and a vaticanol C-like isomer. The isolation of a dimer deriving from the condensation of (+)-catechin with trans-caffeic acid also indicated that other preformed phenolics are structurally modified in tissues infected with P. viticola. Topics: Caffeic Acids; Catechin; Dimerization; Genotype; Hybridization, Genetic; Oomycetes; Plant Diseases; Plant Leaves; Resveratrol; Stilbenes; Vitis | 2011 |
An in vitro screening cascade to identify neuroprotective antioxidants in ALS.
Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease, characterized by progressive dysfunction and death of motor neurons. Although evidence for oxidative stress in ALS pathogenesis is well described, antioxidants have generally shown poor efficacy in animal models and human clinical trials. We have developed an in vitro screening cascade to identify antioxidant molecules capable of rescuing NSC34 motor neuron cells expressing an ALS-associated mutation of superoxide dismutase 1. We have tested known antioxidants and screened a library of 2000 small molecules. The library screen identified 164 antioxidant molecules, which were refined to the 9 most promising molecules in subsequent experiments. Analysis of the in silico properties of hit compounds and a review of published literature on their in vivo effectiveness have enabled us to systematically identify molecules with antioxidant activity combined with chemical properties necessary to penetrate the central nervous system. The top-performing molecules identified include caffeic acid phenethyl ester, esculetin, and resveratrol. These compounds were tested for their ability to rescue primary motor neuron cultures after trophic factor withdrawal, and the mechanisms of action of their antioxidant effects were investigated. Subsequent in vivo studies can be targeted using molecules with the greatest probability of success. Topics: Amyotrophic Lateral Sclerosis; Animals; Antioxidants; Apoptosis; Blood-Brain Barrier; Caffeic Acids; Cell Culture Techniques; Cell Line; Central Nervous System; Humans; Mice; Mice, Inbred C57BL; Motor Neurons; Mutation; Oxidative Stress; Resveratrol; Small Molecule Libraries; Stilbenes; Superoxide Dismutase; Superoxide Dismutase-1; Transgenes; Umbelliferones | 2009 |
Plant catechols and their S-glutathionyl conjugates as antinitrosating agents: expedient synthesis and remarkable potency of 5-S-glutathionylpiceatannol.
With a view to elucidating the structural requisites for effective antinitrosating properties in plant polyphenolics and their metabolites, we have undertaken a comparative investigation of the nitrite scavenging effects of representative catechol derivatives of dietary relevance in the 2,3-diaminonaphthalene (DAN) nitrosation and tyrosine nitration assays. Compounds tested included caffeic acid (1), chlorogenic acid (2), piceatannol (3), hydroxytyrosol (4), and the corresponding S-glutathionyl conjugates 5-8, which were prepared using either tyrosinase (5 and 6) or a novel, o-iodoxybenzoic acid (IBX)-based oxygenation/ conjugation methodology (7b and 8). In the DAN nitrosation assay at pH 4.0, the rank order of inhibitory activities was found to be 5-S-glutathionylpiceatannol (7b) > 3 > 1 > 2 > 2-S-glutathionylcaffeic acid (5) > 2-S-glutathionylchlorogenic acid (6) > 4 approximately 5-S-glutathionylhydroxytyrosol (8). Quite unexpectedly, in the tyrosine nitration assay in 0.5 M HCl, 2 was the most efficient inhibitor followed by 1 > 4 > 3 > 7b approximately 5 > 8 > 6. Under the assay conditions, the glutathionyl conjugates were usually consumed at faster rates than the parent catechols (decomposition rates: 3 > 1 > 4 > 2). The 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) assay indicated that the most effective hydrogen donors were 4 > 7b > 1 approximately 3. Overall, these results indicated that catechol compounds and their glutathionyl conjugates may exhibit profoundly different inhibitory properties depending on the specific conditions of the assay, including especially pH, and that their antinitrosating properties do not correlate tout-court with their hydrogen donor capacity. The glutathionyl-piceatannol conjugate 7b was found to be one of the most potent inhibitors in the physiologically relevant DAN assay and may provide a new structural lead for the design of effective antinitrosating agents based on dietary polyphenolic compounds. Topics: 2-Naphthylamine; Caffeic Acids; Catechols; Chlorogenic Acid; Free Radical Scavengers; Glutathione; Nitrosation; Phenylethyl Alcohol; Plant Extracts; Reactive Nitrogen Species; Stilbenes | 2008 |
The catecholic antioxidant piceatannol is an effective nitrosation inhibitor via an unusual double bond nitration.
Piceatannol (1) was found to be more effective than caffeic acid, an established antinitrosating agent, in inhibiting N-nitrosation of 2,3-diaminonaphthalene. Product analysis of the reaction mixture of 1 (20 microM) with nitrite ions (80 microM) at pH 3.0 and at 37 degrees C showed conversion to a single major nitration product, (E)-3,3',4,5'-tetrahydroxy-beta-nitrostilbene (2) (68% yield). This would result from an unexpected nitration at the double bond sector via the 4-phenoxyl radical, which was analyzed at the unrestricted DFT level. Topics: Antioxidants; Caffeic Acids; Catechols; Ions; Molecular Conformation; Naphthalenes; Nitrates; Nitrites; Nitrosation; Phenols; Plant Oils; Stilbenes | 2006 |
Biosynthesis of plant-specific stilbene polyketides in metabolically engineered Escherichia coli.
Phenylpropanoids are the precursors to a range of important plant metabolites such as the cell wall constituent lignin and the secondary metabolites belonging to the flavonoid/stilbene class of compounds. The latter class of plant natural products has been shown to function in a wide range of biological activities. During the last few years an increasing number of health benefits have been associated with these compounds. In particular, they demonstrate potent antioxidant activity and the ability to selectively inhibit certain tyrosine kinases. Biosynthesis of many medicinally important plant secondary metabolites, including stilbenes, is frequently not very well understood and under tight spatial and temporal control, limiting their availability from plant sources. As an alternative, we sought to develop an approach for the biosynthesis of diverse stilbenes by engineered recombinant microbial cells.. A pathway for stilbene biosynthesis was constructed in Escherichia coli with 4-coumaroyl CoA ligase 1 4CL1) from Arabidopsis thaliana and stilbene synthase (STS) cloned from Arachis hypogaea. E. coli cultures expressing these enzymes together converted the phenylpropionic acid precursor 4-coumaric acid, added to the growth medium, to the stilbene resveratrol (>100 mg/L). Caffeic acid, added in the same way, resulted in the production of the expected dihydroxylated stilbene, piceatannol (>10 mg/L). Ferulic acid, however, was not converted to the expected stilbene product, isorhapontigenin. Substitution of 4CL1 with a homologous enzyme, 4CL4, with a preference for ferulic acid over 4-coumaric acid, had no effect on the conversion of ferulic acid. Accumulation of tri- and tetraketide lactones from ferulic acid, regardless of the CoA-ligase expressed in E. coli, suggests that STS cannot properly accommodate and fold the tetraketide intermediate to the corresponding stilbene structure.. Phenylpropionic acids, such as 4-coumaric acid and caffeic acid, can be efficiently converted to stilbene compounds by recombinant E. coli cells expressing plant biosynthetic genes. Optimization of precursor conversion and cyclization of the bulky ferulic acid precursor by host metabolic engineering and protein engineering may afford the synthesis of even more structurally diverse stilbene compounds. Topics: Acyltransferases; Arabidopsis; Arabidopsis Proteins; Arachis; Biotransformation; Caffeic Acids; Cloning, Molecular; Coenzyme A Ligases; Coumaric Acids; Escherichia coli; Genetic Engineering; Kinetics; Resveratrol; Stilbenes | 2006 |
Protection of lipids from oxidation by epicatechin, trans-resveratrol, and gallic and caffeic acids in intestinal model systems.
Consumption of polyphenols is associated with health promotion through diet, although many are poorly absorbed in animals and humans alike. Lipid peroxides may reach the intestine and initiate deleterious oxidation. Here we measured inhibition of the oxidation of linoleic acid (LA) in authentic fluid from rat small intestine (RIF) by two dietary polyphenols, a flavonoid, epicatechin (EC), and a stilbene, resveratrol (RV), and by gallic (GA) and caffeic (CA) acids, and their partition coefficients. Both polyphenols inhibited 80%, and CA inhibited 65%, of the production of hexanal. GA was the weakest antioxidant in this assay. Interestingly, measuring peroxides production in RIF showed that only epicatechin inhibited the first stage of oxidation. The oxidizing agent, the antioxidant comound, the solution pH and lipophilicity are known to affect the total antioxidative activity. We suggest that the mechanism of this activity changes in accord with the environment: i.e., RV may act as a free radial scavenger, but here, in protecting lipids in intestinal fluid from oxidation, it acts as a hydrogen atom donor. Since the concentration of phenolics is much higher in the intestinal fluid than is ever achieved in plasma or other body tissues, it is suggested that their antioxidant activity could be exerted in the gastrointestinal tract (GIT), breaking the propagation of lipid peroxides oxidation and production of toxic compounds. Topics: Animals; Antioxidants; Body Fluids; Caffeic Acids; Catechin; Gallic Acid; Intestinal Mucosa; Linoleic Acids; Lipid Peroxidation; Male; Models, Biological; Rats; Rats, Sprague-Dawley; Resveratrol; Stilbenes | 2006 |
Plant-derived anti-inflammatory compounds affect MIF tautomerase activity.
The cytokine macrophage migration inhibitory factor (MIF) has recently emerged as a crucial factor in the pathogenesis of rheumatoid arthritis (RA). It is debated whether the MIF mediated tautomeric conversion of either phenylpyruvate or of its other phenolic substrates is implicated in the pro-inflammatory action of this cytokine. Traditional herbal remedies have been used for centuries to alleviate inflammatory ailments of many kinds including arthritis. Several of their active ingredients identified are mono- or poly-phenol derivatives. In the present study the effect of some anti-inflammatory plant phenols on MIF mediated tautomerism of phenylpyruvate was investigated. Curcumin and caffeic acid were found to be the most potent inhibitors, exhibiting IC(50) values in the submicromolar range in the ketonase assay. Resveratrol and umbelliferon were almost as potent inhibitors as the antipyretic-analgetic drug acetaminophen. Our results reveal MIF as a possible target for the herbal anti-rheumatic agents. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis, Rheumatoid; Caffeic Acids; Cattle; Curcumin; Enzyme Inhibitors; Humans; In Vitro Techniques; Intramolecular Oxidoreductases; Kidney; Macrophage Migration-Inhibitory Factors; Phenols; Phenylpyruvic Acids; Phloretin; Phytotherapy; Plants, Medicinal; Resveratrol; Stilbenes | 2005 |
Do wine polyphenols modulate p53 gene expression in human cancer cell lines?
The p53 gene is an established tumor suppressor and an inducer of apoptosis. We here attempt to determine whether the putative anticarcinogenic properties attributed to red wine and its polyphenolic constituents depend, at least in part, upon their ability to modulate p53 expression in cancer cells.. Three human breast cancer cell lines (MCF-7, T47D; MDA-MB-486) and one human colon cancer cell line [Colo 320 HSR (+)] were treated for 24-h with each of four polyphenols [quercetin; (+)-catechin, trans-resveratrol; caffeic acid] at concentrations ranging from 10(-7) M to 10(-4) M, after which, p53 concentrations were measured in cell lysates by a time-resolved fluorescence immunoassay.. None of the polyphenols tested affected p53 expression in the breast cancer cell lines T-47D and MDA-MB-486. p53 content of MCF-7 breast cancer cells (wild-type) was increased by caffeic acid, decreased by resveratrol, and showed a twofold increase with catechin, that reached borderline statistical significance; however, none of these effects were dose-responsive. Colo 320 HSR (+) cells (with a mutant p53 gene) had lower p53 content upon stimulation, reaching borderline statistical significance, but without being dose-responsive, in the presence of caffeic acid and resveratrol. Apart from toxicity at 10(-4) M, quercetin had no effect upon these four cell lines.. The observed p53 concentration changes upon stimulation by polyphenols are relatively small, do not follow a uniform pattern in the four cell lines tested, and do not exhibit a dose-response effect. For these reasons, we speculate that the putative anticarcinogenic properties of wine polyphenols are unlikely to be mediated by modulation of p53 gene expression. Topics: Antioxidants; Breast Neoplasms; Caffeic Acids; Catechin; Colonic Neoplasms; Flavonoids; Fluoroimmunoassay; Gene Expression Regulation, Neoplastic; Genes, p53; Humans; Models, Structural; Phenols; Polymers; Quercetin; Resveratrol; Stilbenes; Time Factors; Tumor Cells, Cultured; Wine | 2001 |