151
|
Anter E, Thomas SR, Schulz E, Shapira OM, Vita JA, Keaney JF. Activation of endothelial nitric-oxide synthase by the p38 MAPK in response to black tea polyphenols. J Biol Chem 2004; 279:46637-43. [PMID: 15333638 DOI: 10.1074/jbc.m405547200] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Black tea improves endothelial function in patients with coronary artery disease. We sought to determine the responsible components of black tea and elucidate the underlying cell signaling mechanisms. We exposed porcine aortic endothelial cells to components of black tea and found that the polyphenol fraction acutely enhanced nitric oxide bioactivity. This effect involved endothelial nitric-oxide synthase (eNOS) phosphorylation at Ser-1177 and dephosphorylation at Thr-495, consistent with increased eNOS activity. These effects were calcium-dependent, as removal of extracellular calcium prevented eNOS phosphorylation at Ser-1177, whereas inhibition of intracellular calcium mobilization with TMB-8 blunted Thr-495 dephosphorylation. Black tea polyphenol-induced eNOS activation appeared dependent upon the phosphatidylinositol 3-kinase-Akt pathway, as it was significantly inhibited by LY294002 and a dominant negative Akt, respectively. Pharmacological inhibition of p38 mitogen-activated protein kinase (p38 MAPK) with either SB202190 or SB203580 as well as overexpression of a dominant negative p38 MAPKalpha attenuated both eNOS activation and phosphorylation changes in response to black tea polyphenols. Inhibition of p38 MAPKalpha also blunted Akt activation in response to black tea polyphenols, suggesting that p38alpha MAPK is upstream of Akt in this pathway. Finally, a constitutively active mutant of MKK6bE, an upstream kinase for p38 MAPK, enhanced both the basal and stimulated activity of Akt, leading to increased eNOS activity. Taken together, these data identify the p38 MAPK as an upstream component of Akt-mediated eNOS activation.
Collapse
Affiliation(s)
- Elad Anter
- Evans Memorial Department of Medicine, the Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachussetts 02118, USA
| | | | | | | | | | | |
Collapse
|
152
|
Kim JY, Han EH, Shin DW, Jeong TC, Lee ES, Woo ER, Jeong HG. Suppression of CYP1A1 expression by naringenin in murine Hepa-1c1c7 cells. Arch Pharm Res 2004; 27:857-62. [PMID: 15460448 DOI: 10.1007/bf02980179] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Naringenin, dietary flavonoid, is antioxidant constituents of many citrus fruits. In the present study, we investigated the effect of naringenin on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible CYP1A1 gene expression in mouse hepatoma Hepa-1c1c7 cells. Naringenin alone did not affect CYP1A1-specific 7-ethoxyresorufin O-deethylase (EROD) activity. In contrast, the TCDD-inducible EROD activities were markedly reduced upon concomitant treatment with TCDD and naringenin in a dose dependent manner. TCDD-induced CYP1A1 mRNA level was also markedly suppressed by naringenin. A transient transfection assay using dioxin-response element (DRE)-linked luciferase and electrophoretic mobility shift assay revealed that naringenin reduced transformation of the aryl hydrocarbons receptor(AhR) to a form capable of specifically binding to the DRE sequence in the promoter of the CYP1A1 gene. These results suggest the down regulation of the CYP1A1 gene expression by either naringenin in Hepa-1c1c7 cells might be antagonism of the DRE binding potential of nuclear AhR.
Collapse
Affiliation(s)
- Ji Young Kim
- Department of Pharmacy, College of Pharmacy, Research Center for Proteineous Materials, Chosun University, Kwangju 501-759, Korea
| | | | | | | | | | | | | |
Collapse
|
153
|
Ying CJ, Xu JW, Ikeda K, Takahashi K, Nara Y, Yamori Y. Tea polyphenols regulate nicotinamide adenine dinucleotide phosphate oxidase subunit expression and ameliorate angiotensin II-induced hyperpermeability in endothelial cells. Hypertens Res 2004; 26:823-8. [PMID: 14621186 DOI: 10.1291/hypres.26.823] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Out-of-control reactive oxygen species (ROS) signaling is one of the key events in the pathogenesis of endothelial dysfunction and essential hypertension. We observed that tea polyphenols decreased the production of ROS via regulation of the protein expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in bovine carotid artery endothelial cells (BCAECs). Both green tea polyphenols (GTP) and black tea polyphenols (BTP) down-regulated the expression of NADPH oxidase subunits p22phox and p67phox while up-regulating catalase expression (p < 0.05, respectively). Pre-treatment with GTP or BTP for 24 h significantly decreased the superoxide anion level (p < 0.05) and permeable fluorescence intensities in Ang II-stimulated BCAECs. A decrease in cell permeability was also observed by pre-treatment with diphenylene iodonium chloride (DPI) or vitamin E (p < 0.05, respectively). The result demonstrates that tea polyphenols alleviate angiotensin (Ang) II-induced hyperpermeability mainly by decreasing ROS production. Our results suggest that tea polyphenols regulate ROS-related protein expression and may be beneficial in preventing endothelial cell dysfunction and development of cardiovascular diseases, including hypertension.
Collapse
Affiliation(s)
- Chen-Jiang Ying
- School of Human Environmental Science, Mukogawa Women's University, Nishinomiya, Japan
| | | | | | | | | | | |
Collapse
|
154
|
Bugianesi R, Salucci M, Leonardi C, Ferracane R, Catasta G, Azzini E, Maiani G. Effect of domestic cooking on human bioavailability of naringenin, chlorogenic acid, lycopene and ?-carotene in cherry tomatoes. Eur J Nutr 2004; 43:360-6. [PMID: 15309458 DOI: 10.1007/s00394-004-0483-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2003] [Accepted: 01/05/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND Epidemiological data showed that tomato and tomato product (sauce, paste) consumption is associated with a protective effect against the development of some chronic-degenerative diseases. Tomato antioxidant bioactive molecules such as carotenoids and polyphenols could be responsible, at least in part, for the healthy effect observed. The bioavailability of these compounds is an essential requirement to sustain their in vivo role. While it is well known that many factors can influence the bioaccessibility of carotenoids from the food matrix, there is little information about the factors affecting phenolic compounds' bioaccessibility. AIM OF THE STUDY This investigation was carried out to evaluate the effect of domestic cooking on the bioavailability in humans of antioxidant molecules after the administration of a test meal containing cherry tomatoes. METHODS A cross-over design was conducted. Subjects (3 females and 2 males) consumed experimental meals containing fresh and cooked cherry tomatoes. Blood collection was performed at different time intervals (0, 2, 4, 6, 8 and 24 h). RESULTS Carotenoid and phenol plasma concentrations were measured. Plasma levels of lycopene and beta-carotene were not significantly different with respect to the baseline after ingestion of both the test meals, while plasma concentrations of naringenin and chlorogenic acid increased significantly with respect to the baseline (P<0.05) after administration of cooked cherry tomatoes, but not after administration of fresh cherry tomatoes. CONCLUSIONS The present study indicated that domestically cooked tomatoes significantly increase naringenin and chlorogenic acid plasma levels. Considering that both naringenin and chlorogenic acid are widely studied for their potential healthy properties, evidence of their bioavailability and of the factors influencing their bioaccessibility is an important tool to sustain the possibility that these polyphenols play a biological role in human physiology.
Collapse
Affiliation(s)
- R Bugianesi
- Antioxidant Research Laboratory, Unit of Human Nutrition, National Institute for Food and Nutrition Research (INRAN), Via Ardeatina 546, 00178 Rome, Italy.
| | | | | | | | | | | | | |
Collapse
|
155
|
Kanaze FI, Kokkalou E, Georgarakis M, Niopas I. Validated high-performance liquid chromatographic method utilizing solid-phase extraction for the simultaneous determination of naringenin and hesperetin in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2004; 801:363-7. [PMID: 14751808 DOI: 10.1016/j.jchromb.2003.11.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Naringenin and hesperetin, the aglycones of the flavanone glucosides naringin and hesperidin occur naturally in citrus fruits. They exert a variety of pharmacological effects such as antioxidant, blood lipid-lowering, anticarcinogenic and inhibit selected cytochrome P-450 enzymes resulting in drug interactions. A specific, sensitive, precise, and accurate solid-phase extraction high-performance liquid chromatographic (HPLC) assay for the simultaneous determination of naringenin and hesperetin in human plasma was developed and validated. After addition of 7-ethoxycoumarin as internal standard, plasma samples were incubated with beta-glucuronidase/sulphatase, and the analytes were isolated from plasma by solid-phase extraction using C(18) cartridges and separated on a C(8) reversed phase column with methanol/water/acetic acid (40:58:2, v/v/v) as the eluent at 45 degrees C. The method was linear in the 10-300 ng/ml concentration range for both naringenin and hesperetin (r>0.999). Recovery for naringenin, hesperetin and internal standard was greater than 76.7%. Intra- and inter-day precision for naringenin ranged from 1.4 to 4.2% and from 1.9 to 5.2%, respectively, and for hesperetin ranged from 1.3 to 4.1% and from 1.7 to 5.1%, respectively. Accuracy was better than 91.5 and 91.3% for naringenin and hesperetin, respectively.
Collapse
Affiliation(s)
- Feras Imad Kanaze
- Department of Pharmacy, School of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | | | | | | |
Collapse
|
156
|
Marnewick JL, Joubert E, Swart P, Van Der Westhuizen F, Gelderblom WC. Modulation of hepatic drug metabolizing enzymes and oxidative status by rooibos (Aspalathus linearis) and Honeybush (Cyclopia intermedia), green and black (Camellia sinensis) teas in rats. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:8113-8119. [PMID: 14690405 DOI: 10.1021/jf0344643] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Rooibos and honeybush teas significantly (P < 0.05) enhanced the activity of cytosolic glutathione S-transferase alpha. A significant (P < 0.05) to marginal (P < 0.1) increase in the activity of the microsomal UDP-glucuronosyl transferase was obtained with unprocessed rooibos and honeybush teas, respectively. Oxidized glutathione (GSSG) levels were significantly (P < 0.05) reduced in the liver of all tea treated rats while reduced glutathione (GSH) was markedly increased in the liver of the herbal tea treated rats. These changes resulted in a significant (P < 0.05) increase in the GSH/GSSG ratio by the unprocessed, processed rooibos and unprocessed honeybush teas. Green and black teas markedly to significantly decreased the oxygen radical absorbance capacity in liver homogenates, respectively. Modulation of phase II drug metabolizing enzymes and oxidative status in the liver may be important events in the protection against adverse effects related to mutagenesis and oxidative damage.
Collapse
Affiliation(s)
- Jeanine L Marnewick
- PROMEC Unit, Medical Research Council, P.O. Box 19070, Tygerberg, 7505 South Africa.
| | | | | | | | | |
Collapse
|
157
|
Choi EJ, Chee KM, Lee BH. Anti- and prooxidant effects of chronic quercetin administration in rats. Eur J Pharmacol 2003; 482:281-5. [PMID: 14660033 DOI: 10.1016/j.ejphar.2003.09.067] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The present study was performed to investigate the effects of chronic administration of quercetin on lipid peroxidation and glutathione concentration in rat liver. Male Sprague-Dawley rats were divided into two groups, one of which was fed a normal diet and the other a vitamin E-free diet. Each of these groups was divided further into three subgroups and treated with quercetin administered orally at either 2 or 20 mg/day or with vehicle for 4 weeks. The concentrations of alpha-tocopherol in serum and liver increased following quercetin treatment, and these increases were significantly greater in rats maintained on a vitamin E-free diet. Quercetin significantly decreased the concentration of malondialdehyde (an indicator of lipid peroxidation) in the liver and this decrease was more pronounced in vitamin E-deprived rats than in those maintained on a normal diet (55-60% and 25-35% decrease in malondialdehyde concentrations, respectively). Quercetin treatment decreased the glutathione concentration and glutathione reductase activity (40 and 34%, respectively) in the liver significantly and to a similar extent in vitamin E-deprived and -undeprived rats. Collectively, these results suggest that quercetin may act not only as an antioxidant, but also as a prooxidant in rats.
Collapse
Affiliation(s)
- Eun Jeong Choi
- Department of Biotechnology, Korea University, Anamdong, Sungbuk, Seoul 136-701, South Korea
| | | | | |
Collapse
|
158
|
Harmon AW, Patel YM. Naringenin inhibits phosphoinositide 3-kinase activity and glucose uptake in 3T3-L1 adipocytes. Biochem Biophys Res Commun 2003; 305:229-34. [PMID: 12745063 DOI: 10.1016/s0006-291x(03)00720-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Previous studies have shown that flavonoids inhibit glucose uptake in cultured cells. In this report, we show that the grapefruit flavanone naringenin inhibited insulin-stimulated glucose uptake in 3T3-L1 adipocytes in a dose-dependent manner. Naringenin acts by inhibiting the activity of phosphoinositide 3-kinase (PI3K), a key regulator of insulin-induced GLUT4 translocation. Although naringenin did not alter the phosphotyrosine status of the insulin receptor, insulin receptor substrate proteins, or PI3K, it did inhibit the phosphorylation of the downstream signaling molecule Akt. In an in vitro kinase assay, naringenin inhibited PI3K activity. A physiologically attainable dose of 6 microM naringenin reduced insulin-stimulated glucose uptake by approximately 20%. This inhibitory effect remained 24h after the removal of naringenin from the culture medium. Collectively, our findings suggest that the regular consumption of naringenin in grapefruit may exacerbate insulin resistance in susceptible individuals via impaired glucose uptake in adipose tissue.
Collapse
Affiliation(s)
- Anne W Harmon
- Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, NC 27599, USA
| | | |
Collapse
|
159
|
van Haaften RIM, Haenen GRMM, Evelo CTA, Bast A. Effect of vitamin E on glutathione-dependent enzymes. Drug Metab Rev 2003; 35:215-53. [PMID: 12959415 DOI: 10.1081/dmr-120024086] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Reactive oxygen species and various electrophiles are involved in the etiology of diseases varying from cancer to cardiovascular and pulmonary disorders. The human body is protected against damaging effects of these compounds by a wide variety of systems. An important line of defense is formed by antioxidants. Vitamin E (consisting of various forms of tocopherols and tocotrienols) is an important fat-soluble, chain-breaking antioxidant. Besides working as an antioxidant, this compound possesses other functions with possible physiological relevance. The glutathione-dependent enzymes form another line of defense. Two important enzymes in this class are the free radical reductase and glutathione S-transferases (GSTs). The GSTs are a family of phase II detoxification enzymes. They can catalyze glutathione conjugation with various electrophiles. In most cases the electrophiles are detoxified by this conjugation, but in some cases the electrophiles are activated. Antioxidants do not act in isolation but form an intricate network. It is, for instance, known that vitamin E, together with glutathione (GSH) and a membrane-bound heat labile GSH-dependent factor, presumably an enzyme, can prevent damaging effects of reactive oxygen species on polyunsaturated fatty acids in biomembranes (lipid peroxidation). This manuscript reviews the interaction between the two defense systems, vitamin E and glutathione-dependent enzymes. On the simplest level, antioxidants such as vitamin E have protective effects on glutathione-dependent enzymes; however, we will see that reality is somewhat more complicated.
Collapse
Affiliation(s)
- Rachel I M van Haaften
- Department of Pharmacology and Toxicology, Faculty of Medicine, Universiteit Maastricht, Maastricht, The Netherlands.
| | | | | | | |
Collapse
|
160
|
Bugianesi R, Catasta G, Spigno P, D'Uva A, Maiani G. Naringenin from cooked tomato paste is bioavailable in men. J Nutr 2002; 132:3349-52. [PMID: 12421849 DOI: 10.1093/jn/132.11.3349] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Naringenin has been shown to exert antiestrogenic, cholesterol-lowering and antioxidant activities, as well as an indirect modulation on the metabolism of many xenobiotics. It is one of the most abundant polyphenols in tomato. Given the widespread consumption of tomato (Lycopersicum esculentum) and tomato-based products, this study was designed to determine whether plasma levels of naringenin were detectable in five men after consumption of a test meal containing 150 mg of cooked tomato paste. Naringenin intake with the test meal was 3.8 mg. Blood was drawn from fasting subjects and 2, 4, 6, 8 and 24 h after the meal. To compare the results with a control, the same meal without tomato paste (control meal) was administered to the same subjects 2 wk later. Analyses were performed using high-performance liquid chromatography coupled with a CoulArray electrochemical detector. The peak plasma concentration was 0.12 +/- 0.03 micro mol/L 2 h after the meal. Unconjugated naringenin was not detected. Naringenin was not detected in plasma at any time after consumption of the control meal. In addition to naringenin, we detected rutin and chlorogenic acid in tomato paste, but these polyphenols and their derivatives (quercetin and caffeic acid) were not detected in plasma at any time. To the best of our knowledge, this is the first study demonstrating naringenin bioavailability in humans after consumption of a meal containing cooked tomato paste.
Collapse
Affiliation(s)
- Rossana Bugianesi
- Antioxidant Research Laboratory, National Institute for Food and Nutrition Research, 546-00178 Rome, Italy.
| | | | | | | | | |
Collapse
|
161
|
Cosentino F, Volpe M. Antihypertensive effect and end-organ protection of flavonoids: some insights, more questions. J Hypertens 2002; 20:1721-4. [PMID: 12195110 DOI: 10.1097/00004872-200209000-00013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
162
|
Erlund I, Silaste ML, Alfthan G, Rantala M, Kesäniemi YA, Aro A. Plasma concentrations of the flavonoids hesperetin, naringenin and quercetin in human subjects following their habitual diets, and diets high or low in fruit and vegetables. Eur J Clin Nutr 2002; 56:891-8. [PMID: 12209378 DOI: 10.1038/sj.ejcn.1601409] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2001] [Revised: 12/13/2001] [Accepted: 12/14/2001] [Indexed: 11/09/2022]
Abstract
OBJECTIVES To determine the fasting plasma concentrations of quercetin, hesperetin and naringenin in human subjects consuming their habitual diets, and diets either high or low in fruit and vegetables. To investigate whether plasma concentrations of flavanones can serve as biomarkers of their intake. DESIGN This was a cross-over, strictly controlled dietary intervention consisting of a 2 week baseline period, and two 5 week dietary periods with a 3 week wash-out period in between. The low-vegetable diet contained few fruit and vegetables and no citrus fruit. The high-vegetable diet provided various fruits and vegetables daily including on average one glass of orange juice, one-half orange and one-half mandarin. SUBJECTS Thirty-seven healthy females. RESULTS The high-vegetable diet provided 132 mg of hesperetin and 29 mg of naringenin. The low-vegetable diet contained no flavanones. The mean plasma hesperetin concentration increased from 12.2 nmol/l after the low-vegetable diet to 325 nmol/l after the high-vegetable diet. The respective increase for naringenin was from <73.5 nmol/l for all subjects to a mean value of 112.9 nmol/l. The mean plasma quercetin concentration was 52 nmol/l after the baseline period, during which habitual diets were consumed, and it did not change significantly during the intervention. Interindividual variation in the plasma levels of hesperetin and naringenin was marked and, after the baseline and wash-out periods, and the low-vegetable diet, a majority of the samples had plasma flavanone levels below the limit of detection. After the high-vegetable diet, hesperetin and naringenin were detectable in 54 and 22% of all samples. Quercetin was detectable in nearly all samples after all study periods. CONCLUSION Hesperetin, naringenin and quercetin are bioavailable from the diet, but the plasma concentrations of hesperetin and naringenin are poor biomarkers of intake.
Collapse
Affiliation(s)
- I Erlund
- Biomarker Laboratory, National Public Health Institute (KTL), Helsinki, Finland.
| | | | | | | | | | | |
Collapse
|
163
|
Lee MK, Bok SH, Jeong TS, Moon SS, Lee SE, Park YB, Choi MS. Supplementation of naringenin and its synthetic derivative alters antioxidant enzyme activities of erythrocyte and liver in high cholesterol-fed rats. Bioorg Med Chem 2002; 10:2239-44. [PMID: 11983521 DOI: 10.1016/s0968-0896(02)00059-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The antioxidative effects of naringenin (1) and its synthetic derivative, naringenin 7-O-cetyl ether (2), were tested. Male rats were fed a 1 g/100 g high-cholesterol diet for 6 weeks with supplements of either 1 or 2 (0.073 mmol/100 g diet) to study the effects on the antioxidant enzyme activities in the erythrocyte and liver. The erythrocyte catalase (CAT) and superoxide dismutase (SOD) activities were significantly higher in the compounds 1 or 2 supplemented groups than in the control group, whereas the hepatic SOD and CAT activities were significantly lower in the compound 2 supplemented group. The compounds 1 and 2 supplements to a high cholesterol diet lowered or tended to lower the plasma TBARS levels, that is, lipid peroxide products, while enhancing the plasma paraoxonase activity. These results indicate that the supplementation of 1 and 2 was effective in improving the antioxidant capacity of the erythrocyte and liver, plus the synthetic functional compound 2 appeared to be as potent as 1 in enhancing the antioxidant defense system.
Collapse
Affiliation(s)
- Mi-Kyung Lee
- Department of Food Science and Nutrition, Kyungpook National University, Taegu, South Korea
| | | | | | | | | | | | | |
Collapse
|
164
|
Lee JC, Lim KT, Jang YS. Identification of Rhus verniciflua Stokes compounds that exhibit free radical scavenging and anti-apoptotic properties. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1570:181-91. [PMID: 12020808 DOI: 10.1016/s0304-4165(02)00196-4] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Rhus verniciflua Stokes (RVS) is a widely used herbal plant with various biological properties. Our previous study using cultured neuronal cells showed that an ethanol extract of RVS had strong antioxidant properties. In this study, we characterized the antioxidant activity of the RVS ethanol extract and identified the active compounds responsible for this activity. From the RVS ethanol extract, we derived three water-eluted fractions and another three fractions eluted by organic solvents, and determined that the water-eluted fractions are what protect against reactive oxygen species (ROS) generated by iron and enzymes. Water-eluted fraction F(2) was the most efficient antioxidant. Moreover, DNA fragmentation and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining experiments revealed that F(2) also protects against thymocyte apoptosis mediated by hydroxyl radicals. Finally, EI-MS, (1)H-NMR, and (13)C-NMR spectra signals confirmed that the fraction contained flavonoid derivatives, including fustin, quercetin, butein, and sulfuretin. These results suggest that the flavonoid derivatives in F(2) are the compounds in the RVS ethanol extract that act as antioxidants.
Collapse
Affiliation(s)
- Jeong-Chae Lee
- Division of Biological Sciences and The Research Center for Bioactive Materials, Chonbuk National University, Chonju 561-756, South Korea
| | | | | |
Collapse
|
165
|
Bestwick CS, Milne L. Quercetin modifies reactive oxygen levels but exerts only partial protection against oxidative stress within HL-60 cells. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1528:49-59. [PMID: 11514098 DOI: 10.1016/s0304-4165(01)00167-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Quercetin may contribute to the protection afforded by fruit- and vegetable-rich diets against diseases for which excess production of reactive oxygen species (ROS) has been implicated as a causal or contributory factor. We examine the effect of short term (90 min) quercetin (1-100 microM) exposure on the progress of menadione induced oxidative stress within HL-60 cells. 2',7'-dichlorofluorescein and rhodamine-123 fluorescence, resulting from oxidation of the ROS-sensitive dyes dichlorodihydrofluorescein and dihydrorhodamine-123 respectively, were utilised as indicators of general ROS levels. Ethidium fluorescence, resulting from oxidation of dihydroethidium, was used as a potentially more specific indicator of O(2)(-). Exposure to quercetin alone induced a decrease in DCF and rhodamine fluorescence. Conversely, ethidium fluorescence was enhanced by treatment with >or=40 microM quercetin. Incubation with 1-100 microM quercetin reduced the extent of menadione-induced increase in DCF and rhodamine fluorescence but the menadione-induced increase in ethidium fluorescence was further elevated for cells treated with >or=25 microM quercetin. Exposure to >or=10 microM quercetin abrogated menadione-induced DNA single-strand breaks but, paradoxically, quercetin exacerbated membrane damage and failed to enhance the viability of menadione-challenged cells. In conclusion, quercetin exerts only site-specific protection against oxidative stress.
Collapse
Affiliation(s)
- C S Bestwick
- Antioxidant and DNA Damage Group, Cellular Integrity Programme, Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
| | | |
Collapse
|
166
|
Abstract
In aqueous solution, ascorbate potently prevents bleaching of cytochrome c on exposure to excess H2O2 or t-butyl hydroperoxide. Ascorbate failed to protect cytochrome c in the presence of liposomes of mitochondrial membranelike composition. Like the redox mediator N,N,N,'N'-tetramethyl-p-phenylenediamine (TMPD), however, the bioflavonoids epicatechin and quercetin restored the protection afforded by ascorbate in the presence of liposomes and gave further protection. The quercetin glycoside, rutin, was much less effective, as was the vitamin E analog Trolox. In the presence of liposomes, quercetin alone was relatively ineffective, but cooperated with ascorbate to extend protection synergistically. The results bear specific implications in antioxidant protection of cytochrome c and in moderation of its hydroperoxidase activities in biological membranes. The data also reveal a situation where ascorbate is without effect except in the presence of a bioflavonoid, and substantiate a possibly vital role for certain bioflavonoids in mediating electron transfer from ascorbate into a hydrophobic environment.
Collapse
Affiliation(s)
- B Bandy
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, SP, Brazil.
| | | |
Collapse
|
167
|
Duffy SJ, Keaney JF, Holbrook M, Gokce N, Swerdloff PL, Frei B, Vita JA. Short- and long-term black tea consumption reverses endothelial dysfunction in patients with coronary artery disease. Circulation 2001; 104:151-6. [PMID: 11447078 DOI: 10.1161/01.cir.104.2.151] [Citation(s) in RCA: 354] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Epidemiological studies suggest that tea consumption decreases cardiovascular risk, but the mechanisms of benefit remain undefined. Endothelial dysfunction has been associated with coronary artery disease and increased oxidative stress. Some antioxidants have been shown to reverse endothelial dysfunction, and tea contains antioxidant flavonoids. Methods and Results-- To test the hypothesis that tea consumption will reverse endothelial dysfunction, we randomized 66 patients with proven coronary artery disease to consume black tea and water in a crossover design. Short-term effects were examined 2 hours after consumption of 450 mL tea or water. Long-term effects were examined after consumption of 900 mL tea or water daily for 4 weeks. Vasomotor function of the brachial artery was examined at baseline and after each intervention with vascular ultrasound. Fifty patients completed the protocol and had technically suitable ultrasound measurements. Both short- and long-term tea consumption improved endothelium- dependent flow-mediated dilation of the brachial artery, whereas consumption of water had no effect (P<0.001 by repeated-measures ANOVA). Tea consumption had no effect on endothelium-independent nitroglycerin-induced dilation. An equivalent oral dose of caffeine (200 mg) had no short-term effect on flow-mediated dilation. Plasma flavonoids increased after short- and long-term tea consumption. CONCLUSIONS Short- and long-term black tea consumption reverses endothelial vasomotor dysfunction in patients with coronary artery disease. This finding may partly explain the association between tea intake and decreased cardiovascular disease events.
Collapse
Affiliation(s)
- S J Duffy
- Evans Department of Medicine and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
| | | | | | | | | | | | | |
Collapse
|
168
|
Satterfield M, Brodbelt JS. Structural characterization of flavonoid glycosides by collisionally activated dissociation of metal complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2001; 12:537-549. [PMID: 11349951 DOI: 10.1016/s1044-0305(01)00236-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Collisionally activated dissociation is used for structural characterization of a series of flavonoid glycosides. Dissociation of transition metal/flavonoid binary complexes of the type [MII(L - H+)]+ and transition metal/2,2'-bipyridine/flavonoid ternary complexes of the type [MII(L - H+)bpy]+ give fragmentation patterns that are complementary and more diagnostic than those of the protonated, deprotonated, or sodium-cationized flavonoids. Analysis of fragmentation patterns of the [MII(L - H+)bpy]- complexes permits determination of the disaccharide as a rutinose or neohesperidose and the relative placement of the disaccharide (i.e., 3 vs. 7 positions).
Collapse
Affiliation(s)
- M Satterfield
- Department of Chemistry and Biochemistry, University of Texas at Austin, 78712, USA
| | | |
Collapse
|
169
|
Csala M, Szarka A, Margittai E, Mile V, Kardon T, Braun L, Mandl J, Bánhegyi G. Role of Vitamin E in Ascorbate-Dependent Protein Thiol Oxidation in Rat Liver Endoplasmic Reticulum. Arch Biochem Biophys 2001; 388:55-9. [PMID: 11361140 DOI: 10.1006/abbi.2000.2260] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Addition of ascorbate or its generation from gulonolactone causes the oxidation of protein thiols and a simultaneous dehydroascorbate formation in rat liver microsomes. The participation of vitamin E in the phenomenon was studied. We measured ascorbate and protein thiol oxidation and lipid peroxidation in vitamin E deficient liver microsomes. Vitamin E deficiency partly uncoupled the two processes: ascorbate oxidation increased, while protein thiol oxidation decreased. These changes were accompanied with an accelerated lipid peroxidation in the vitamin E-deficient microsomes, which indicates the accumulation of reactive oxygen species. All these effects were reduced by the in vitro addition of vitamin E to the deficient microsomes, supporting its direct role in the process. The results demonstrate that vitamin E is a component of the protein thiol oxidizing machinery in the hepatic endoplasmic reticulum transferring electrons from the thiol groups towards oxygen.
Collapse
Affiliation(s)
- M Csala
- Department of Medical Chemistry, Semmelweis University, Budapest, Hungary
| | | | | | | | | | | | | | | |
Collapse
|
170
|
van Haaften RI, Evelo CT, Haenen GR, Bast A. No reduction of alpha-tocopherol quinone by glutathione in rat liver microsomes. Biochem Pharmacol 2001; 61:715-9. [PMID: 11266656 DOI: 10.1016/s0006-2952(01)00545-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The cell membrane is protected against lipid peroxidation by endogenous antioxidants such as vitamin E (alpha-tocopherol). The oxidised form of alpha-tocopherol (alpha-tocopherol quinone) does not have this antioxidant function. However, the literature indicates that alpha-tocopherol quinone can be reduced to alpha-tocopherol in vivo and thereby will add to the total antioxidant potential (Moore AN, Ingold KU. Free Radic Biol Med 1997;22:931-4). We found that GSH (reduced glutathione) did not mediate the reduction of alpha-tocopherol quinone, either directly in solution or in rat liver microsomes fortified with alpha-tocopherol quinone. This renders GSH a less likely candidate for alpha-tocopherol quinone reduction in vivo. In addition, alpha-tocopherol quinone did not enhance GSH-dependent protection against lipid peroxidation, either in control microsomes, or in vitamin E-extracted microsomes. Indeed, alpha-tocopherol quinone blocked GSH-dependent protection against lipid peroxidation in vitamin E-extracted microsomes. This indicates that alpha-tocopherol quinone can act as a pro-oxidant.
Collapse
Affiliation(s)
- R I van Haaften
- Department of Pharmacology and Toxicology, Faculty of Medicine, Universiteit Maastricht, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | | | | | | |
Collapse
|
171
|
Cesquini M, Tenor A, Torsoni M, Stoppa G, Pereira A, Ogo S. Quercetin Diminishes the Binding of Hemoglobin to the Red Blood Cell Membrane. ACTA ACUST UNITED AC 2001. [DOI: 10.1089/109454501750225695] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- M. Cesquini
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - A.C. Tenor
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - M.A. Torsoni
- Universidade Braz Cubas, Mogi das Cruzes, SP, Brasil
| | - G.R. Stoppa
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - A.L. Pereira
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| | - S.H. Ogo
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brasil
| |
Collapse
|
172
|
Erlund I, Meririnne E, Alfthan G, Aro A. Plasma kinetics and urinary excretion of the flavanones naringenin and hesperetin in humans after ingestion of orange juice and grapefruit juice. J Nutr 2001; 131:235-41. [PMID: 11160539 DOI: 10.1093/jn/131.2.235] [Citation(s) in RCA: 347] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The flavanones naringenin and hesperetin exhibit estrogenic, anticarcinogenic and antioxidative properties. Orange juice and grapefruit juice contain high amounts of these compounds, and therefore their intake from the diet can be relatively high. No data are available regarding plasma concentrations or plasma kinetics of flavanones. The objectives of this study were to develop methods allowing the analysis of naringenin and hesperetin from plasma and urine and to study their plasma kinetics and urinary excretion. We also wanted to assess whether plasma or urine flavanone concentrations can be used as biomarkers of intake. Healthy volunteers ingested orange juice (five women and three men) or grapefruit juice (two women and three men) once (8 mL/kg). Eleven blood samples and urine were collected between 0 and 24 h after juice administration. Flavanones were analyzed by HPLC with electrochemical detection. Naringenin and hesperetin were bioavailable from the studied juices, but interindividual variation in bioavailability was remarkable. The resulting plasma concentrations were comparatively high, and the peak plasma concentrations (C(max)) were 0.6 +/- 0.4 micromol/L (means +/- SD) for naringenin from orange juice and 6.0 +/- 5.4 micromol/L for naringenin from grapefruit juice. The corresponding value for hesperetin from orange juice was 2.2 +/- 1.6 micromol/L. The elimination half-lives were between 1.3 and 2.2 h, and therefore plasma concentrations reflect short-term intake. The relative urinary excretion varied depending on the flavanone source and dose and was 30.2 +/- 25.5% and 1.1 +/- 0.8% for naringenin from grapefruit juice and orange juice, respectively, and 5.3 +/- 3.1% for hesperetin from orange juice. The considerable difference in the relative urinary excretion of naringenin from the two juices was most likely caused by dose-dependent renal clearance rather than differences in bioavailability (as indicated by the similar C(max)-to-dose ratios). The results indicate that urine flavanone concentrations are not good biomarkers of dietary intake. We conclude that because of the relatively high concentrations of flavanones in plasma after ingestion of orange juice or grapefruit juice, considerable health effects could ensue in individuals consuming them regularly.
Collapse
Affiliation(s)
- I Erlund
- Department of Nutrition, National Public Health Institute (KTL), Mannerheimintie 166 F, FIN-00300 Helsinki, Finland.
| | | | | | | |
Collapse
|