Ascorbic acid and copper in linoleate oxidation. II. Ascorbic acid and copper as oxidation catalysts

Haase, G.; Dunkley, W.L.

doi:10.1016/s0022-2275(20)43050-0

Cited by 53 publications

(3 citation statements)

References 26 publications

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“…Stimulation of lipid peroxidation by a high concentration of vitamin C is well documented (Haase and Dunkley, 1969;Dumelin and Tappel, 1977). Further increase of peroxidation in erythrocytes by high vitamin C supplementation of animals that could be counterbalanced by more vitamin E was recently reported by Chen (1981).…”

Section: Discussionmentioning

confidence: 87%

Vitamin C and E: an antioxidative system against herbicide-induced lipid peroxidation in higher plants

Finckh¹,

Kunert²

1985

J. Agric. Food Chem.

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Section: Discussionmentioning

confidence: 87%

Vitamin C and E: an antioxidative system against herbicide-induced lipid peroxidation in higher plants

Finckh¹,

Kunert²

1985

J. Agric. Food Chem.

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“…In living cells these can originate from metal ions or from enzymatic reactions which involve NADPH and electron transport. This may explain the view expressed by some authors that in certain instances lipid peroxidation is an enzymatic process (Warner & Lands 1961;Ansell & Spanner 1965;May & McCay 1968), while in other systems peroxidation is known to he dependent only on the presence of trace elements (Barber 1963;Haase & Dunkley 1969). Ferrous iron is strongly catalytic because of the ease with which it donates electrons; ascorbate functions presumably by maintaining iron in the reduced state.…”

Section: Discussionmentioning

confidence: 92%

Lipid peroxides in spermatozoa; formation, r‏‏‏‏‏ôle of plasmalogen, and physiological significance

Jones

Mann

1976

Proc. R. Soc. Lond. B.

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In view of the high content of unsaturated fatty acids in the phospholipids of mammalian spermatozoa, the possibility was investigated that during aerobic incubation of spermatozoa these fatty acids, in particular arachidonic (20:4) and docosahexanoic (22:6) acid, undergo peroxidation, which in turn is responsible for the decline in viability of spermatozoa. The formation of lipid peroxides was followed by the thiobarbituric acid (TBA) reaction, iodometry and fluorimetry; it was found that during aerobic incubation of washed ram spermatozoa at 37 °C in the presence of ascorbic acid (0.1 mg/ml) and ferrous iron (2.8 μg Fe/ml), peroxides became detectable after 30 min incubation and their level reached a maximum after 60 min. Coincident with the formation of peroxides motility declined and the spermatozoa became agglutinated, but their oxygen uptake was not grossly different from that of motile spermatozoa in mixtures free of ascorbic acid or Fe. Peroxide formation could be prevented by the addition of either chelating agents, such as EDTA and sodium citrate, or antioxidants, such as tocopherol and butylated hydroxyanisole, to the incubation medium. Conclusive evidence that the substrate for the peroxidation reaction is a lipid, was obtained by extracting lipids from spermatozoa with chloroform: methanol and incubating aerobically in the presence of catalytic amounts of ascorbate and Fe, two fractions: the extracted lipid and the ‘defatted’ sperm residue; very high peroxide values were recorded in the former, but not the latter fraction. Examination by thin-layer and gas-liquid chromatography of the phospholipid and neutral lipid fractions obtained from spermatozoa, revealed that peroxidation caused a loss of approximately 50% in the content of plasmalogens, 20:4 and 22:6 fatty acids, and palmitaldehyde. Changes in the other phospholipids and their bound fatty acids were relatively small, but there was some increase in the amount of a substance which behaved chromatographically as lysolecithin. The content of cholesterol and glycerides in the neutral lipid fraction was not appreciably different in non-peroxidized and peroxidized spermatozoa, but the latter contained a higher proportion of free fatty acids. Our results indicate that under aerobic conditions the lipids in spermatozoa, in particular the plasmalogens, are susceptible to peroxidation. The peroxidation reaction apparently takes place within the lipoprotein, and is associated with a decline in the viability of spermatozoa. This decline could be due either to an increase in cellular permeability resulting from changes in membrane-bound lipids, or to a direct toxic effect of lipid peroxides on spermatozoa. Development of means for the prevention of adverse effects of the peroxidation reaction, may be of practical importance in relation to the problem of long-term storage of semen for artificial insemination.

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“…Linoleic acid peroxidation is widely studied in different model systems, including liposomes [ 31 ], but in most cases the rate of lipid peroxidation is estimated from the kinetics of formation of lipid peroxidation products [ 32 , 33 , 34 , 35 ]. Several other techniques have been previously used to estimate the initiation rate of lipid peroxidation, but in most cases these also relied on the detection of the products, for example, conjugated lipid hydroperoxides [ 36 ].…”

Section: Introductionmentioning

confidence: 99%

Antioxidant Activity of Deferasirox and Its Metal Complexes in Model Systems of Oxidative Damage: Comparison with Deferiprone

et al. 2021

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Deferasirox is an orally active, lipophilic iron chelating drug used on thousands of patients worldwide for the treatment of transfusional iron overload. The essential transition metals iron and copper are the primary catalysts of reactive oxygen species and oxidative damage in biological systems. The redox effects of deferasirox and its metal complexes with iron, copper and other metals are of pharmacological, toxicological, biological and physiological importance. Several molecular model systems of oxidative damage caused by iron and copper catalysis including the oxidation of ascorbic acid, the peroxidation of linoleic acid micelles and the oxidation of dihydropyridine have been investigated in the presence of deferasirox using UV-visible and NMR spectroscopy. Deferasirox has shown antioxidant activity in all three model systems, causing substantial reduction in the rate of oxidation and oxidative damage. Deferasirox showed the greatest antioxidant activity in the oxidation of ascorbic acid with the participation of iron ions and reduced the reaction rate by about a 100 times. Overall, deferasirox appears to have lower affinity for copper in comparison to iron. Comparative studies of the antioxidant activity of deferasirox and the hydrophilic oral iron chelating drug deferiprone in the peroxidation of linoleic acid micelles showed lower efficiency of deferasirox in comparison to deferiprone.

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Ascorbic acid and copper in linoleate oxidation. II. Ascorbic acid and copper as oxidation catalysts

Cited by 53 publications

References 26 publications

Vitamin C and E: an antioxidative system against herbicide-induced lipid peroxidation in higher plants

Vitamin C and E: an antioxidative system against herbicide-induced lipid peroxidation in higher plants

Lipid peroxides in spermatozoa; formation, r‏‏‏‏‏ôle of plasmalogen, and physiological significance

Antioxidant Activity of Deferasirox and Its Metal Complexes in Model Systems of Oxidative Damage: Comparison with Deferiprone

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