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1.
The aim of this study was to evaluate the antiatherosclerotic effect of commercially available phenolic-rich extracts from grape seeds (ExGrape seeds, EGS; grape seed extract, GSE) and marc (ExGrape total, EGT) in cholesterol-fed hamsters and to investigate possible operating mechanisms. These extracts fed at a moderate dose mimicking two glasses of red wine per meal reduced plasma cholesterol (-11% on average) but did not affect plasma antioxidant capacity of hamsters. The extracts prevented the development of aortic atherosclerosis by 68% (EGS), 63% (EGT), and 34% (GSE). Elsewhere, in an ex vivo experiment using rat aortic rings, EGS (7 microg/mL) induced 77% endothelium-dependent relaxation, whereas EGT and GSE (30 microg/mL) induced 84 and 72%, respectively. These results suggests that phenolic extracts from grape seeds and marc are beneficial in inhibiting atherosclerosis by indirect mechanism(s).  相似文献   

2.
The effect of addition of grape seed tannins on the phenolic composition, chromatic characteristics, and antioxidant activity of red wine was studied. Two highly pure commercial grape seed tannins (GSE100 and GSE300) were selected, and their phenolic compositions were determined. Two types of red wines were made with Castela?o/Tinta Miu?da (3/2, w/w) grapevine varieties by fermentation on skin using two different maceration times, which correspond to the wines rich and poor in polyphenols, respectively. Each of these wines was used for experimentation with the addition of GSE100 and GSE300 before and immediately after alcoholic fermentation. Phenolic composition, chromatic characteristics, and antioxidant activity of the finished red wines were analyzed by HPLC-DAD, CIElab 76 convention, and DPPH radical test, respectively. The results showed that the addition of grape seed tannins had obvious effects of increasing color intensity and antioxidant activity only in the wines poor in polyphenols. Although GSE300 contained much higher amounts of di- and trimer procyanidins and a lower amount of polymeric proanthocyanidins, it provided effects of increasing the color intensity and antioxidant activity of the wines poor in polyphenols similar to those of GSE100. Furthermore, GSE100 released more gallic acid to wines than GSE300, although no gallic acid was detected in GSE100. Tannins added after alcoholic fermentation had a better effect on phenolic composition of red wine than tannins added before alcoholic fermentation.  相似文献   

3.
Dietary antioxidants may provide a cost-effective strategy to promote health in obesity by targeting oxidative stress and inflammation. We recently found that the antioxidant-rich grape skin extract (GSE) also exerts a novel anti-hyperglycemic activity. This study investigated whether 3-month GSE supplementation can improve oxidative stress, inflammation, and hyperglycemia associated with a Western diet-induced obesity. Young diet-induced obese (DIO) mice were randomly divided to three treatment groups (n = 12): a standard diet (S group), a Western high fat diet (W group), and the Western diet plus GSE (2.4 g GSE/kg diet, WGSE group). By week 12, DIO mice in the WGSE group gained significantly more weight (24.6 g) than the W (20.2 g) and S groups (11.2 g); the high fat diet groups gained 80% more weight than the standard diet group. Eight of 12 mice in the W group, compared to only 1 of 12 mice in the WGSE group, had fasting blood glucose levels above 140 mg/dL. Mice in the WGSE group also had 21% lower fasting blood glucose and 17.1% lower C-reactive protein levels than mice in the W group (P < 0.05). However, the GSE supplementation did not affect oxidative stress in diet-induced obesity as determined by plasma oxygen radical absorbance capacity, glutathione peroxidase, and liver lipid peroxidation. Collectively, the results indicated a beneficial role of GSE supplementation for improving glycemic control and inflammation in diet-induced obesity.  相似文献   

4.
Recent studies dramatically showed that the removal of circulating modified low-density lipoprotein (LDL) results in complete prevention of atherosclerosis. The gastrointestinal tract is constantly exposed to food, some of it containing oxidized compounds. Lipid oxidation in the stomach was demonstrated by ingesting heated red meat in rats. Red wine polyphenols added to the rats' meat diet prevented lipid peroxidation in the stomach and absorption of malondialdehyde (MDA) in rat plasma. In humans, postprandial plasma MDA levels rose by 3-fold after a meal of red meat cutlets. MDA derived from meat consumption caused postprandial plasma LDL modification in human. The levels of plasma MDA showed a 75% reduction by consumption of red wine polyphenols during the meat meal. Locating the main biological site of action of polyphenols in the stomach led to a revision in the understanding of how antioxidants work in vivo and may help to elucidate the mechanism involved in the protective effects of polyphenols in human health.  相似文献   

5.
Proteomics analysis of rat brain protein modulations by grape seed extract   总被引：6，自引：0，他引：6  
Dietary supplements such as grape seed extract (GSE) enriched in proanthocyanidins (PA) (oligomeric polyphenols) have been suggested to have multiple health benefits, due to antioxidant and other beneficial activities of the PA. However, a systematic analysis of the molecular basis of these benefits has not been demonstrated. Because the brain is vulnerable to age-related oxidative damage and other insults including inflammation, it was hypothesized that rats ingesting GSE would experience changes in expression or modifications of specific brain proteins that might protect against pathologic events. Normal adult female rats were fed diets supplemented with 5% GSE for 6 weeks. Proteomics analysis (2D electrophoresis and mass spectrometry) of brain homogenates from these animals identified 13 proteins that were altered in amount and/or charge. Because many of these changes were quantitatively in the opposite direction from previous findings for the same proteins in either Alzheimer disease or mouse models of neurodegeneration, the data suggest that these identified proteins may mediate the neuroprotective actions of GSE. This is the first identification and quantitation of specific proteins in mammalian tissues modulated by a dietary supplement, as well as the first to demonstrate links of such proteins with any disease.  相似文献   

6.
Oxidative modification of low-density lipoprotein (LDL) particles is a key event in the development of atherosclerosis. Oxidized LDL induces oxidative stress and modifies gene expression in endothelial cells. Berries constitute a rich dietary source of phenolic antioxidants. We found that the endemic Chilean berry Aristotelia chilensis (ach) has higher phenol content and scores better for total radical-trapping potential and total antioxidant reactivity in in vitro antioxidant capacity tests, when compared to different commercial berries. The juice of ach is also effective in inhibiting copper-induced LDL oxidation. In human endothelial cell cultures, the addition of ach juice significantly protects from hydrogen peroxide-induced intracellular oxidative stress and is dose-dependent. The aqueous, anthocyanin-rich fraction of ach juice accounts for most of ach's antioxidant properties. These results show that ach is a rich source of phenolics with high antioxidant capacity and suggest that it may have antiatherogenic properties.  相似文献   

7.
Grape seed extract (GSE) has been reported to exert protective effects on various forms of cardiac disorders. The cardiovascular protective effects of GSE are believed to be ascribed to its antioxidative properties. A series of studies have demonstrated that polyphenols are instrumental for the antioxidative properties of GSE. This study was undertaken to investigate whether two major polyphenols isolated from GSE (catechin and proanthocyanidin B4) could increase the endogenous antioxidant enzymes in cardiomyocytes, and whether such increased cellular defenses could provide protection against oxidative cardiac cell injury. Incubation of cardiac H9C2 cells with micromolar concentrations of catechin or proanthocyanidin B4 resulted in a significant induction of cellular antioxidant enzymes in a concentration-dependent fashion. Furthermore, catechine or proanthocyanidin B4 pretreatment led to a marked reduction in xanthine oxidase (XO)/xanthine-induced intracellular reactive oxygen species (ROS) accumulation and cardiac cell apoptosis. These results indicated that grape seed polyphenols (GSP) could protect against cardiac cell apoptosis via the induction of endogenous antioxidant enzymes. This may be an important mechanism underlying the protective effects of GSE observed with various forms of cardiovascular disorders.  相似文献   

8.
Native propolis was defined as propolis powder collected from the continental part of Croatia and prepared according to a patented process that preserves all the propolis natural nutritional and organoleptic qualities. Nine phenolic compounds (out of thirteen tested) in propolis sample were detected by high performance liquid chromatography (HPLC) analysis. Among them chrysin was the most abundant (2478.5 microg/g propolis). Contrary to moderate antioxidant activity of propolis examined in vitro (ferric reduction antioxidant power; FRAP-assay), propolis as a food supplement modulated antioxidant enzymes (AOE) and significantly decreased lipid peroxidation processes (LPO) in plasma, liver, lungs, and brain of mice. The effect was dose- and tissue-dependent. The lower dose (100 mg/kg bw) protected plasma from oxidation, whereas the higher dose (300 mg/kg bw) was pro-oxidative. Hyperoxia (long-term normobaric 100% oxygen) increased LPO in all three organs tested. The highest vulnerability to oxidative stress was observed in lungs where hyperoxia was not associated with augmentation of AOE. Propolis protected lungs from hyperoxia by increased catalase (CAT) activity. This is of special importance for lungs since lungs of adult animals are highly vulnerable to oxidative stress because of their inability to augment AOE activity. Because of its strong antioxidant and scavenging abilities, native propolis might be used as a strong plant-based antioxidant effective not only in physiological conditions but also in cases that require prolonged high concentration of oxygen.  相似文献   

9.
Lower antioxidant activity in white wines in comparison to red wines lies in the low grape-skin-derived polyphenol content. This paper reports the analysis of the antioxidant capacities of white wine samples obtained along two different processing procedures directed to enrich the wine with polyphenols. White wine samples derived from whole squeezed grapes stored for increasing periods of time (up to 18 h) contained increasing concentrations of polyphenols (from 0.35 to 0.55 mmol/L) and, in parallel, exhibited increased capacity to scavenge free radicals and to inhibit copper ion-induced low-density lipoprotein (LDL) oxidation. However, addition of increasing concentrations of alcohol (up to 18%) to the whole squeezed grapes remarkably augmented the extraction of grape skin polyphenols into the wine up to 1.25 mmol/L, resulting in an increased capacity of the wine to scavenge free radicals and to inhibit LDL oxidation, to an extent similar to that of red wine. The extent of LDL oxidation inhibition was directly related to the wine polyphenolic content (r = 0.986). It is concluded that processing white wine by imposing a short period of grape skin contact in the presence of alcohol leads to extraction of grape skin polyphenols and produces polyphenol-rich white wine with antioxidant characteristics similar to those of red wine.  相似文献   

10.
Paracetamol is an antipyretic analgesic widely used globally. It has been recurrently found in water bodies and is known to elicit toxic effects in aquatic species; however, its potential ability to induce oxidative stress in sentinel species remains unknown The objective was to establish a methodology to evaluate the toxicity elicited on the sentinel species Hyalella azteca by paracetamol-enriched sediment using oxidative stress tests. Concentrations used in assays were determined using the previously obtained median lethal concentration (72?h LC50). The following oxidative stress biomarkers were evaluated: lipid peroxidation (LPO), protein carbonyl content (PCC) in order to determine oxidized protein content, and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). LPO and PCC increased significantly while SOD, CAT, and GPX decreased significantly (p?<?0.05) with respect to controls. Paracetamol induces oxidative stress on H. azteca, and the set of tests employed is helpful in evaluating the toxicity of this group of pharmaceuticals on aquatic species.  相似文献   

11.
To determine the stomach bioreactor capability for food oxidation or antioxidation, rats were fed red turkey meat cutlets (meal A) or red turkey meat cutlets and red wine concentrate (meal B). The hydroperoxides (LOOH) and malondialdehyde (MDA) levels of the stomach contents were evaluated during and after digestion; the postprandial plasma MDA level was also evaluated. In independently fed rats, the stomach LOOH concentration fell substantially 90 min following the meal, and the addition of red wine polyphenols enhanced LOOH reduction 3-fold. A similar trend was obtained for MDA. After pyloric ligation, the stomach contents of rats fed red meat homogenate showed >2-fold increases in LOOH and MDA accumulation. The postprandial plasma MDA level increased significantly by 50% following meal A and was maintained or even fell by 34% below basal level following meal B. The findings show that consumption of partially oxidized food could increase lipid peroxidation in the stomach and the absorption of cytotoxic lipid peroxidation products into the body. The addition of antioxidants such as red wine polyphenols to the meal may alter these outcomes. These findings explain the potentially harmful effects of oxidized fats in foods and the important benefit of consuming dietary polyphenols during the meal.  相似文献   

12.
Cranberry products and especially cranberry juice (CJ) have been consumed for health reasons primarily due to their effect on urinary tract infections. We investigated the quantity of both free and total (after hydrolysis) phenolic antioxidants in cranberry products using the Folin assay. The order of amount of total polyphenols in cranberry foods on a fresh weight basis was as follows: dried > frozen > sauce > jellied sauce. On a serving size basis for all cranberry products, the order was as follows: frozen > 100% juice > dried > 27% juice > sauce > jellied sauce. High fructose corn syrup (HFCS) is a major source of sugar consumption in the U.S. and contains both glucose and fructose, potential mediators of oxidative stress. We investigated the effect of the consumption of HFCS and ascorbate with CJ antioxidants or without CJ (control) given to 10 normal individuals after an overnight fast. Plasma antioxidant capacity, glucose, triglycerides, and ascorbate were measured 6 times over 7 h after the consumption of a single 240 mL serving of the two different beverages. The control HFCS caused a slight decrease in plasma antioxidant capacity at all time points and thus an oxidative stress in spite of the presence of ascorbate. CJ produced an increase in plasma antioxidant capacity that was significantly greater than control HFCS at all time points. Postprandial triglycerides, due to fructose in the beverages, were mainly responsible for the oxidative stress and were significantly correlated with the oxidative stress as measured by the antioxidant capacity. Cranberries are an excellent source of high quality antioxidants and should be examined in human supplementation studies.  相似文献   

13.
Orange juice is a source of antioxidants that might afford in vivo protection from oxidative stress. To test this hypothesis, we carried out a human intervention study with blood orange juice containing high amounts of vitamin C, anthocyanins, and carotenoids. Sixteen healthy female volunteers were enrolled in a crossover study and were given 600 mL/day of blood orange juice or a diet without juice for 21 days. Before and after each intervention period, plasma vitamin C, cyanidin-3-glucoside, and carotenoids were quantified. Furthermore, plasma antioxidant capacity, malondialdehyde concentration in plasma, 11-dehydrotromboxane B(2) urinary excretion, and lymphocyte DNA damage were evaluated as biomarkers of oxidative stress. Blood orange juice consumption determined a significant increase in plasma vitamin C, cyanidin-3-glucoside, beta-cryptoxanthin, and zeaxanthin. Also, lymphocyte DNA resistance to oxidative stress was improved whereas no effect was observed on the other markers that we analyzed. In turn, these results suggest that blood orange juice is a bioavailable source of antioxidants, which might moderately improve the antioxidant defense system; however, the long-term effects of its consumption are to be further investigated.  相似文献   

14.
The effect of a single oral administration of proanthocyanidins, oligomeric and polymeric polyhydroxyflavan-3-ol units, on the antioxidative potential of blood plasma was studied in rats. Proanthocyanidin-rich extract from grape seeds was administered by intragastric intubation to fasted rats at 250 mg/kg of body weight. The plasma obtained from water- or proanthocyanidin-administered rats was oxidized by incubation with copper sulfate or 2, 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) at 37 degrees C, and the formation of cholesteryl ester hydroperoxides (CE-OOH) was followed. The plasma obtained from proanthocyanidin-administered rats was significantly more resistant against both copper ion-induced and AAPH-induced formation of CE-OOH than that from control rats. The lag phase in the copper ion-induced oxidation of rat plasma was remarkably increased at 15 min after administration of proanthocyanidins and reached a maximum level at 30 min. When the plasma from proanthocyanidin-administered rat was hydrolyzed by sulfatase and beta-glucuronidase following analysis by high-performance liquid chromatography with electrochemical detection, metabolites of proanthocyanidins occurred in rat plasma at 15 min after administration, three peaks of which were identified as gallic acid, (+)-catechin, and (-)-epicatechin. These results suggest that the intake of proanthocyanidins, the major polyphenols in red wine, increases the resistance of blood plasma against oxidative stress and may contribute to physiological functions of plant food including wine through their in vivo antioxidative ability.  相似文献   

15.
为探讨葡萄籽提取物(GSE)对采后猕猴桃接种青霉菌后青霉病的防治效果,本试验以贵长猕猴桃为试材,通过测定猕猴桃果实发病率、病斑直径以及与果实抗病相关物质的含量和防御相关酶的活性,研究GSE对采后猕猴桃果实青霉菌的作用效果。结果表明,GSE处理延迟了猕猴桃在损伤接种扩展青霉(Penicillium expansum)后果实发病率的上升,抑制了果实病斑直径的扩大。同时,GSE处理极显著提高了猕猴桃果实总酚和总类黄酮含量,降低了膜降解标志性代谢产物丙二醛(MDA)含量以及脂氧合酶(LOX)活性,提高了猕猴桃果实几丁质酶(CHI)、β-1,3葡聚糖酶(GLU)和过氧化物酶(POD)活性。接种扩展青霉后,接种前期GSE处理显著提高了果实的多酚氧化酶(PPO)活性,接种后期GSE处理显著提高了苯丙氨酸氨解酶(PAL)活性。综上,GSE处理通过激活抗氧化防御代谢从而提高了猕猴桃果实对青霉病的抗性。本研究为利用GSE防治青霉病研究提供了理论指导和技术参考。  相似文献   

16.
Antioxidants such as vitamin C, vitamin E, and carotenoids have been reported to prevent the progression of experimentally induced cataracts. However, little is known of the effect of procyanidins, a powerful antioxidant, on cataract formation. This paper investigates the anticataract activity of grape seed extract (GSE, which contains 38.5% procyanidins) in hereditary cataractous rats (ICR/f rats). The ICR/f rats were fed a standard diet containing 0 or 0.213% GSE [0.082% procyanidins in the diet (w/w)] for 27 days. The GSE significantly prevented and postponed development of cataract formation by evaluation of slit lamp observations of the rats' eyes. Lens weight and malondialdehyde concentration in the lens and plasma cholesteryl ester hydroperoxide (ChE-OOH) level induced by CuSO4 were significantly lower in the GSE group compared with the control group. The rats were also fed for 14 days either the diet containing 0.085% procyanidin dimer to tetramer fraction (0.085% as the procyanidins), the diet containing 0.090% procyanidin pentamer to heptamer fraction (0.085% as the procyanidins), or the diet containing 0.093% procyanidin oligomers more than decamer fraction (0.085% as the procyanidins). The ChE-OOH levels in the procyanidin pentamer to heptamer and procyanidin oligomers more than decamer groups were significantly lower than in the procyanidin dimer to tetramer group. These results suggested that procyanidins and their antioxidative metabolites prevented the progression of cataract formation by their antioxidative action. The larger molecular procyanidins in the GSE might contribute this anticataract activity.  相似文献   

17.
Among the most extensively used compounds for the pest control in Argentinean crops is the organochlorine endosulfan. The sublethal effects of the commercial endosulfan formulation on hematology and lipid peroxidation (LPO) of the neotropical fish Prochilodus lineatus were investigated. Firstly, we calculated acute toxicity (LC50) in order to define sublethal concentrations (0, 1.2, and 2.4 ??g L?1). Hematological and oxidative stress responses were assessed at 24, 48, and 96 h. Endosulfan exposure significantly diminished the hemoglobin concentration, mean cell hemoglobin, and total plasma protein and increased white blood cells count and plasma glucose after 96 h. Exposed fish showed an alteration of the differential leukocytes count, evidenced by more thrombocytes and monocytes and less lymphocytes and neutrophils. Endosulfan increased LPO levels in intestine, liver, and brain in both sublethal concentrations. The present results suggest that endosulfan produces biochemical and physiological alterations, including immunological disorders, and it is a good inductor of oxidative stress in P. lineatus.  相似文献   

18.
Antioxidative activity of green tea polyphenol in cholesterol-fed rats   总被引：17，自引：0，他引：17  
This study investigated the effects of green tea polyphenol on the serum antioxidative activity and cholesterol levels of cholesterol-fed rats and compared them with those of probucol, an antioxidant hypocholesterolemic agent. To evaluate the antioxidative activity, the susceptibility to oxidative modification of low-density lipoprotein (LDL) isolated from the serum of cholesterol-fed rats was measured, as was the serum antioxidative activity using the spontaneous autoxidation system of brain homogenate. Administration of green tea polyphenol effectively inhibited LDL oxidation and elevated serum antioxidative activity to the same degree as probucol. However, higher amounts of polyphenol than probucol needed to be administered to reduce the total, free, and LDL cholesterol levels. Furthermore, green tea polyphenol increased the levels of high-density lipoprotein (HDL) cholesterol, leading to dose-dependent improvement of the atherogenic index, an effect that was not seen with probucol. Thus, green tea polyphenol may exert an antiatherosclerotic action by virtue of its antioxidant properties and by increasing HDL cholesterol levels.  相似文献   

19.
Gladiolus corms were grown in media contaminated with cadmium (Cd) (50 mg kg?1) and supplemented with silicon (Si) and potassium (K). The role of Si and K for mitigation of Cd toxicity was evaluated. Cd-induced stress generated significantly increased level of oxidative stress markers including hydrogen peroxide (H2O2), and malondialdehyde (MDA) in gladiolus. The application of K and Si improved the production of protein and proline in the treated plants. Moreover, K and Si supplemented plants exhibited an improvement in the activity of antioxidant enzymes and a reduction in the level of MDA, H2O2 and Cd uptake under Cd stress. Application of K and Si also enhanced the uptake of mineral nutrients including calcium (Ca), magnesium (Mg), manganese (Mn), sulfur (S) and K. The plants supplemented with K and Si exhibited a higher amount of total phenolics and flavonoids. The combined effect of Si and K was more pronounced regarding beneficial effects on gladiolus plants compared to individual effect of these elements under Cd stress. The current research reveals that Si and K may improve gladiolus growth by decreasing the oxidative stress and Cd uptake and by increasing the activity of antioxidant defense enzymes, the quantity of secondary metabolites and plant nutrition.  相似文献   

20.
We evaluated the protective potential of anthocyanins from purple sweet potato Ipomoea batatas cultivar Ayamurasaki (APSP) against low-density lipoprotein (LDL) oxidation in vitro and atherosclerotic lesion development in apolipoprotein E-deficient mice given a cholesterol- and fat-enriched diet with or without 1% APSP for 4 weeks. APSP protected LDL against oxidation more potently than other anthocyanins and l-ascorbic acid in vitro. In mice, APSP significantly lowered the atherosclerotic plaque area to about half of the control, the liver level of thiobarbituric acid-reactive substances as an oxidative stress marker, and the plasma level of soluble vascular cell adhesion molecule-1 (sVCAM-1). However, APSP showed no effects on body weight and cholesterol and lipid levels in the plasma. The results suggest that APSP can suppress the development of atherosclerotic lesions and both enhancements of oxidative stress and sVCAM-1 independently of the changes in cholesterol and lipid levels in mice.  相似文献   

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