Enzymatic lipid peroxidation

Sies, 1993). One might reasonably conclude, therefore, that it is unlikely that non-enzymatic lipid peroxidation could have any role to play in human disease (Father et al., 1990). 

In this chapter the generation of free radicals, mainly superoxide and nitric oxide, catalyzed by prooxidant enzymes will be considered. Enzymes are apparently able to produce some other free radicals (for example, HO and N02), although their formation is not always rigorously proved or verified. The reactions of such enzymes as lipoxygenase and cyclooxygenase also proceed by free radical mechanism, but the free radicals formed are consumed in their catalytic cycles and probably not to be released outside. Therefore, these enzymes are considered separately in Chapter 26 dedicated to enzymatic lipid peroxidation. 

Antioxidant effect. Alcohol (50%) extract of the ginger produced significant effect on enzymatic lipid peroxidation. The extract dose-dependently inhibited oxidation of fatty acid and linoleic acid in the presence... 

Formation of hybrid adducts with acetaldehyde and malondialdehyde (MAA adducts) has been shown to act in a synergistic manner and may be involved in the stabilisation of protein adducts in vivo. Malondialdehyde (HOCH=CH-CHO) is a highly reactive dialdehyde originating from the non-enzymatic lipid peroxidation of a variety of unsaturated fatty acids. 

Anti-inflammatory activity was studied on two labdane derivatives isolated from S. javalambrensis [122-124], that also contains other known diterpenoids [98,99,125]. These two products, ent-13-epi-12a-acetoxy-manoyloxide (76) and e t-8a-hydroxy-labda-13(16), 14-diene (98) were evaluated for anti-inflammatory action in vitro in the concentration range 10 7 M to 10 4 M and were compared with aspirin, sodium salicylate and indomethacine neither compound affected superoxide generation or scavenging and nor did inhibit non-enzymatic lipid peroxidation. These two natural products interact with the eicosanoid system, perhaps at the phospholipase level, but do not interfere with the other tested leukocyte functions or with reactive oxygen species, and are essentially non-toxic to... 

Inhibition of enzymatic and non enzymatic lipid peroxidation in microsomcs, rat liver and kidney, and induced by different agents [87, 108-113]... 

Nagababu, E. and Lakshmaiah, N., Inhibitory effect of eugenol on non-enzymatic lipid peroxidation in rat Ever mitochondria, Biochem. Pharmacol, 43,2393,1992. 

Yamamoto. S. Enzymatic lipid peroxidation, reactions of mammalians lipoxygenases. Free Radical Biology and Medicine, 10,149-159.1991. 

Musgrave ME, Gould SP, Ablett RF (1987) Enzymatic lipid peroxidation in the gonadal and hepatopancreatic microsomal fraction of cultivated mussels Mytilus edulis L.). J Food Sci 52 609-612... 

Yamamoto, S. (1991) Enzymatic lipid peroxidation reactions of mammalian lipoxygenases. Free Radical Biol. Med. 10, 149-159. 

Sddergren, E, Cederberg, J, Vessby, B and Basu, S (2001) Reduction of non-enzymatic and enzymatic lipid peroxidation with vitamin E supplementation in experimental hepatotox-icity. Eur JNutr, 40, 10-16. 

Narayan, M.S., Naidu, K.A., Ravishankar, G.A., Srinivas, L. Venkataraman, L.V (1999). Antioxidant effect of anthocyanin on enzymatic and non-enzymatic lipid peroxidation. Prostaglandins, Leukotrienes, and Essential Fatty Acids, 60, 1-4. 

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