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Turchi G, Alagona G, Lubrano V. Protective activity of plicatin B against human LDL oxidation induced in metal ion-dependent and -independent processes. Experimental and theoretical studies. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2009; 16:1014-1026. [PMID: 19427772 DOI: 10.1016/j.phymed.2009.03.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 02/10/2009] [Accepted: 03/24/2009] [Indexed: 05/27/2023]
Abstract
Oxidation of low-density lipoproteins (LDL) is thought to be a major factor in the pathophysiology of atherosclerosis. Natural antioxidants have been shown to protect LDL from oxidation and to inhibit atherogenic developments in animals. Structurally related prenylated pterocarpans, erybraedin C and bitucarpin A, and the prenylchalcone plicatin B were examined for their ability to inhibit LDL oxidation in vitro. The kinetic profile of peroxidation is characterized by the lag time of oxidation (t(lag)), the maximal rate of oxidation (V(max)) and the maximal accumulation of oxidation products (OD(max)). Specific variation of the set of kinetic parameters by antioxidants may provide important information about the mechanism of inhibitory action of a given compound. At equimolar concentrations (1 microM) the prenylated derivatives tested were found to inhibit 1 microM copper sulphate-induced oxidation of LDL (50 microg protein/ml) in accordance with the following order of activity: plicatin B>erybraedin Cbitucarpin A. Structural aspects, such as hydrogen-donating substituents, their number and arrangement in the aromatic ring moieties, and the prenyl and methoxy substituents, were investigated in order to explain the findings obtained. It is well known that the antioxidant activity of flavonoids is believed to be caused by a combination of transition metal chelation and free-radical-scavenging activities. To investigate these differences we comparatively studied the protective mechanism of plicatin B in copper-dependent or -independent LDL oxidation. The latter was mediated by 2,2'-azo-bis-(2-amidinopropane) dihydrochloride (ABAP). We measured the formation of conjugated dienes (OD(234 nm)). Plicatin B (0.2-1.5 microM) delayed the Cu(2+) (1 microM) promoted oxidation as conjugate diene formation (t(lag)) of the LDL by 45.2-123.5 min and reduced V(max) by 0.46-0.29 microM/min. In the ABAP (0.2mM) promoted LDL oxidation t(lag) increased by 67.2-110.2 min through plicatin B (0.5-2.5 microM). In experiments in which Cu(2+) concentrations increased (0.5 - 3 microM) and the amount of plicatin B (1 microM) was maintained constant, a significant decrease in t(lag) and an increase in V(max) was observed. In this study plicatin B appeared to exhibit a mixed mechanism, interfering with the formation of the radicals by chelating copper involved in the initiation/propagation reaction, but also by scavenging free hydroperoxyl radicals resulting from ABAP thermolysis. In addition, theoretical analysis indicated that plicatin B preferentially established the chelating complex with Cu(2+), because its affinity value is notably higher (by a factor of 5) than that for Cu(+).
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Affiliation(s)
- G Turchi
- Biochemistry and Mutagenesis in Somatic Cell Units, IBF - CNR, 56124 Pisa, Italy.
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Zhang Q, van der Klift EJ, Janssen HG, van Beek TA. An on-line normal-phase high performance liquid chromatography method for the rapid detection of radical scavengers in non-polar food matrixes. J Chromatogr A 2009; 1216:7268-74. [DOI: 10.1016/j.chroma.2009.08.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 08/13/2009] [Accepted: 08/17/2009] [Indexed: 10/20/2022]
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Castelo-Branco VN, Torres AG. Potential application of antioxidant capacity assays to assess the quality of edible vegetable oils. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/lite.200900035] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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105
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Gökmen V, Serpen A, Fogliano V. Direct measurement of the total antioxidant capacity of foods: the ‘QUENCHER’ approach. Trends Food Sci Technol 2009. [DOI: 10.1016/j.tifs.2009.03.010] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ugartondo V, Mitjans M, Torres JL, Vinardell MP. Biobased epicatechin conjugates protect erythrocytes and nontumoral cell lines from H2O2-induced oxidative stress. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:4459-4465. [PMID: 19361155 DOI: 10.1021/jf900240a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This paper reports the study of the protective action of epicatechin and epicatechin derivatives, obtained by depolymerizing polymeric flavanols in the presence of cysteine or cysteamine, on red blood cells (RBC) and nontumoral cell lines challenged by exogenous H(2)O(2). The epicatechin derivatives showed more effective antioxidant properties than epicatechin. Among them, 4β-(2-aminoethylthio)epicatechin 3-O-gallate showed the highest antioxidant activity against three markers of oxidative stress: hemolysis, lipid peroxidation, and cytotoxicity. Furthermore, as this compound lacks the pyrogallol group on the condensed flavanic structure, it might be safer than other potent gallocatechin-type polyphenols. These findings indicate that these epicatechin derivatives, which are byproducts of the agro-food industry show potential for application in the food and drug industries.
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Affiliation(s)
- Vanessa Ugartondo
- Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, 08028 Barcelona, Spain
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Waisundara VY, Hsu A, Tan BKH, Huang D. Baicalin improves antioxidant status of streptozotocin-induced diabetic Wistar rats. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:4096-4102. [PMID: 19364111 DOI: 10.1021/jf8028539] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This study investigated the antioxidant and antidiabetic effects of baicalin, as well as its effects in combination with the antidiabetic drug metformin. Three groups of streptozotocin-induced diabetic rats were given the following treatments for 30 days: (1) 500 mg/kg metformin; (2) 120 mg/kg baicalin; (3) 500 mg/kg metformin + 120 mg/kg baicalin. In addition, vehicle-treated diabetic and nondiabetic controls were used in the experiment. The rats treated with baicalin and metformin + baicalin had significantly elevated (p < 0.05) hepatic activities of superoxide dismutase, catalase, and glutathione peroxidase compared with the vehicle- and metformin-treated groups. Plasma and hepatic lipid peroxide concentrations of the baicalin- and baicalin + metformin-treated groups were significantly reduced (p < 0.05). In addition, baicalin significantly reduced plasma and hepatic triglycerides and cholesterol levels. The study thus showed that baicalin mitigated oxidative stress as well as enhanced the antidiabetic effect of metformin by improving the antioxidant status.
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Affiliation(s)
- Viduranga Y Waisundara
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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108
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Papoti VT, Tsimidou MZ. Impact of sampling parameters on the radical scavenging potential of olive (Olea europaea L.) leaves. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:3470-3477. [PMID: 19334682 DOI: 10.1021/jf900171d] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The impact of sampling parameters, that is, cultivar, leaf age, and sampling date, on the radical scavenging potential of olive leaf extracts was examined via the DPPH(*) and other assays. Total phenol content was estimated colorimetrically and by fluorometry, whereas phenol composition was assessed by RP-HPLC coupled with diode array, fluorometric, and MS detection systems. Oleuropein was not always the major leaf constituent. Considerable differences noted in individual phenol levels (hydroxytyrosol, oleuropein and other secoiridoids, verbascoside, and flavonoids) among samples were not reflected either in the total phenol content or in the radical scavenging potential of the extracts. It can be suggested that olive leaf is a robust source of radical scavengers throughout the year and that differentiation in the levels of individual components depends rather on sampling period than on cultivar or age. The latter does not present predictable regularity. Exploitation of all types of leaves expected in an olive tree shoot for the extraction of bioactive compounds is feasible.
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Affiliation(s)
- Vassiliki T Papoti
- Department of Chemistry, Laboratory of Food Chemistry and Technology, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
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Pun PBL, Gruber J, Tang SY, Schaffer S, Ong RLS, Fong S, Ng LF, Cheah I, Halliwell B. Ageing in nematodes: do antioxidants extend lifespan in Caenorhabditis elegans? Biogerontology 2009; 11:17-30. [PMID: 19350411 DOI: 10.1007/s10522-009-9223-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Accepted: 03/23/2009] [Indexed: 12/21/2022]
Abstract
Antioxidants are often investigated as a promising strategy for extending lifespan. Accordingly, there is significant interest in novel antioxidant compounds derived from natural sources such as plant extracts. However, because lifespan studies are laborious and expensive to conduct, candidate compounds are frequently selected based simply on their in vitro antioxidant efficacy, with the implicit assumption that in vitro antioxidants are also in vivo antioxidants, and that in vivo antioxidants will decrease functionally relevant oxidative damage and thereby extend lifespan. We investigated the validity of these assumptions in the model organism, Caenorhabditis elegans. Nematodes were exposed to 6 plant extracts, selected out of a total of 34 based on a simple in vitro antioxidant assay. We found no correlation between in vitro and in vivo antioxidant capacities. Antioxidant efficacies were also not predictive of lifespan benefits. Further studies into those extracts that produced significant lifespan extension indicated that a direct antioxidant effect is unlikely to be the main factor responsible for the modulation of nematode lifespan.
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Affiliation(s)
- Pamela Boon Li Pun
- Department of Biochemistry, Ageing/Neurobiology Programme, Centre for Life Sciences, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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Time course of changes in serum oxidant/antioxidant status in overfed obese rats and their offspring. Clin Sci (Lond) 2009; 116:669-80. [DOI: 10.1042/cs20080413] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The aim of the present study was to determine the time course of changes in oxidant/antioxidant status, as well as serum glucose, insulin, leptin and lipid levels, liver adipose tissue and muscle lipid and protein contents, in cafeteria-diet-fed dams during gestation and lactation, and in their offspring throughout adulthood. Food intake was also evaluated. The cafeteria diet induced a significant increase in maternal body and relative adipose tissue weights, daily energy intake, and plasma glucose, insulin, leptin and lipid levels at parturition (day 0) and at the end of lactation (day 21). Plasma total antioxidant status [ORAC (oxygen radical absorbance capacity)], erythrocyte catalase and SOD (superoxide dismutase) activities were lower, whereas plasma hydroperoxide and carbonyl protein levels were higher in cafeteria-diet-fed mothers compared with control mothers at days 0 and 21. Pups from cafeteria-diet-fed dams, both males and females, also had consistently higher body and relative adipose tissue weights, and plasma glucose, insulin, leptin, triacylglycerol (triglyceride) and cholesterol levels at birth (day 0), weaning (day 21) and 3 months of age (day 90). These offspring had significantly lower ORAC and catalase activity, and higher plasma hydroperoxide and carbonyl protein levels and SOD activity at birth, at days 21 and 90 compared with control offspring. In conclusion, excessive maternal fat and energy intake can play an important role in the development of metabolic disorders in the offspring. Maternal oxidative stress may be among the responsible factors. Fetal oxidative stress may present an additional confounding influence and probably contributes to additional disorders, aggravating features of the metabolic syndrome. An improvement in maternal oxidant/antioxidant status during pregnancy and lactation, with adequate nutrition, could have beneficial effects on the progeny.
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Ulrich-Merzenich G, Zeitler H, Vetter H, Kraft K. Synergy research: vitamins and secondary plant components in the maintenance of the redox-homeostasis and in cell signaling. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2009; 16:2-16. [PMID: 19118991 DOI: 10.1016/j.phymed.2008.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2008] [Accepted: 11/20/2008] [Indexed: 05/27/2023]
Abstract
The maintenance of the redox-homeostasis is an essential task of antioxidants. Reactive oxygen species (ROS) formed during oxidative stress can potentially damage the normal cellular functions and support pathological processes like atherosclerosis in vessels or malignant growth in other tissues, but also the aging process. However, recent findings link ROS also to cell survival and/or proliferation, which revolutionises the age-old dogmatic view of ROS being exclusively involved in cell damage and death. Low concentrations of hydrogenperoxide e.g. are involved in cell signaling and can activate mitogen-activated kinases (MAPK) to initiate cell growth. Nutritional antioxidants like vitamin C or E can promote endothelial cell growth, but can also inhibit growth of muscle cells, and influence MAPK. Thus, keeping the redox-homeostasis in a steady state especially in the context of tissue regeneration appears to be more important than previously known and seems to be a controlled synergistic action of antioxidants and ROS. The present review summarizes the properties and functions of ROS and nutritional antioxidants like the vitamins C and E, and polyphenols in redox-homeostasis. Their relevance in the treatment of various diseases is discussed in the context of a multitarget therapy with nutraceuticals and phytotherapeutic drugs.
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Paula FS, Kabeya LM, Kanashiro A, de Figueiredo AS, Azzolini AEC, Uyemura SA, Lucisano-Valim YM. Modulation of human neutrophil oxidative metabolism and degranulation by extract of Tamarindus indica L. fruit pulp. Food Chem Toxicol 2009; 47:163-70. [DOI: 10.1016/j.fct.2008.10.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Revised: 10/08/2008] [Accepted: 10/26/2008] [Indexed: 12/01/2022]
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