Lipid peroxidation and oxidative

In summary, unoxidized lycopene can act as a lipid and a DNA antioxidant at physiological concentrations but oxidized lycopene or high concentrations of lycopene, and depending upon the oxidizing conditions, may increase lipid peroxidation and oxidative DNA damage. Furthermore, the pro-oxidant effects may result in an increased apoptosis and a decreased cell viability, which should be kept in mind as studies on proliferation and apoptosis are reviewed. 

Matos, HR, P Di Mascio, and MHG Medieros. 2000. Protective effect of lycopene on lipid peroxidation and oxidative DNA damage in cell culture. Arch Biochem Biophys 383(1) 56—59. 

The superoxide anion (O2 ) exhibits numerous physiological toxic effects including endothelial cell damage, increased microvascular permeability, formation of chemotactic factors such as leukotriene B4, recruitment of neutrophils at sites of inflammation, lipid peroxidation and oxidation, release of cytokines, DNA singlestrand damage, and formation of peroxynitrite anion (ONOO-), a potent cytotoxic and proinflammatory molecule generated according to equation 7.210 ... 

Therefore, the metabolite interferes with mitochondrial function and decreases the production of ATP and other important cofactors such as NADH and FADH. Therefore, after repeated use of the drug, mitochondrial integrity is reduced and cellular and overall liver fat oxidation is inhibited. Consequently, fat accumulates, seen as microvesicular steatosis. Electron microscopy shows swollen mitochondria and damaged mitochondrial structures. The accumulated lipid may encourage lipid peroxidation and oxidative stress to occur, causing further damage. 

Ames, B.N., Hollstein, M.C. Cathcart, R. (1981) Lipid peroxidation and oxidative damage to DNA. In Yagi K., ed.. Lipid Peroxide in Biology and Medicine, New York, Academic Press, pp. 339-351... 

Abuja, P.M. andAlbertini, R. (2001) Methods for monitoring oxidative stress, lipid peroxidation and oxidation resistance of lipoproteinOn. Chim. Acta, 306 1-17. 

Fig. 7.3 Reactions showing the generation of ROS during lipid peroxidation and oxidative stress. Hydroxyl radical ( OH) lipid radical ( lipid), peroxyl radical (lipid-OO ) lipid peroxide (lipid-OOH) nitric oxide ( NO) nitrogen dioxide (N02) peroxynitrite anion (ONOO-) hypochlorous acid (HOC1), and hydrogen peroxide (H202)...

Dipyridamole has also been shown to have antioxidant effects (19). Antioxidants act to remove harmful reactive-oxygen species and protect low-density lipoproteins (LDL) from oxidation oxidized LDL plays a key role in the development and propagation of atherosclerosis. The antioxidant effects of dipyridamole may be both direct (by scavenging oxygen and hydroxyl radicals, inhibiting lipid peroxidation and oxidative modification of LDL) (20-22) and indirect (via adenosine, which reduces superoxide anion generation). Dipyridamole has been shown to be a more effective anioxidant than ascorbic acid, alpha-tocopherol, or probucol (22). 

In addition to cytochrome P-450 induction, other diet induced metabolic effects are likely to be involved in carcinogenesis. High temperature processing or long-term storage of foods with attendant exposure to oxygen can lead to the formation of lipid peroxides and oxidized sulfur amino acids in the food. The partially oxidized S-amino acids cystine monoxide (CMO) and methionine sulfoxide (MSO) are nutritionally available, but require in vivo conversion to the reduced amino acids at the... 

Hart, C. M., Tolson, J. K., and Block, E. R., 1991, Supplemental fatty adds alter lipid peroxidation and oxidant injury in endothelial cells, Am. J. Physiol. 260 L481-488. 

It is well known that lipid peroxidation, DNA singlestrand breaks, and other forms of DNA damage occur in response to oxidative stress (Ames et al, 1982). Depletion of reduced glutathione also commonly precedes or accompanies lipid peroxidation and oxidative stress (Muldoon and Stohs, 1991 Omar et al, 1990). In an in vivo study, the effects of ricin administered orally on hepatic lipid peroxidation, nonprotein sulfhydryl content, and DNA singlestrand breaks were assessed in mice (Muldoon et al, 1992). The incidence of hepatic DNA damage increased 2.9-, 2.8-, and 2.4-fold relative to control values at 24, 36, and 48 h post-treatment with ricin, respectively. Hepatic nonprotein sulfhydryl concentration decreased significantly from 51 to 65% to control values at 24, 36, and 48 h post-treatment (Figures 25.2 and 25.3). 

Crocus sativus (Saffron, Safranal). Saffron (Crocus sativus) and its active metabolite safranal display neuropharmacological effects with anxiolytic, anticonvulsant, and neuroprotective activity. Safranal decreases quinolinic acid-induced lipid peroxidation and oxidative DNA damage, and prevents the decrease of hippocampal thiol redox and antioxidant status produced by quinolinic acid [242],... 

The formation of Fe(IV) = 0 Lb suggests that the Fe(III) center is oxidized by only one of the two oxidizing equivalents from the peroxide. The fate of the second equivalent has been the subject of much study. In early work, in which the ability of Fe(III) Lb/H202 mixtures to initiate lipid peroxidation and oxidation of organic molecules was examined, it was postulated that the second oxidizing equivalent was released as a hydroxyl radical ... 

There is also intriguing evidence that (co-3) fatty acids induce apo B degradation via mechanisms that do not involve the conventional proteasomal or lysosomal degradation pathways. In the presence of (cu-3) fatty acids, apo B degradation was shown to occur in a post-ER, pre-secretion process (E.A. Fisher, 2004). Lipid peroxidation and oxidative stress mechanisms were implicated in the increased degradation and decreased secretion of apo... 

Mercury induces lipid peroxidation and oxidative stress and involves changes in the glutathione level (Fukino et al., 1984 Rana et al., 1995). 

E. Isoprostanes as Indicators of Lipid Peroxidation and Oxidant Injury... 

ROS can initiate embryonic-fetal lipid peroxidation and oxidatively damage proteins and DNA, all or any one of which could adversely affect embryonic-fetal... 

Ascorbic acid is the major water-soluble antioxidant present in cells and plasma. It will quench reactive oxygen species as 02 (Nishikimi 1975), HO (Bielski et aL 1975), and O2 (Bodannes and Chan 1979). On the other hand, it reduces Fe to Fe and thus will stimulate Fenton catalysis of H2O2 —> HO. Hydroperoxide-dependent lipid peroxidation in rat liver microsomes was enhanced by ascorbic acid (Laudicina and Marnett 1990). Ascorbic acid protected cardiac microsomes against lipid peroxidation and oxidative damage (Mukhopadhyay et al. 1993). It diminished both luminol- and lucigenin-amplified H2O2 derived chemiluminescence in concentrations > 10" (Klinger et al. 1996). 

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