Peroxidation, lipids

Peroxide oxidation processes in human organism are one of based phenomena that is responsible for homeostasis. For this reason development and investigation of interaction mechanism between different biomacromolecules and lipids peroxide are important for forming complete picture of functioning of human being as biological system. 

Following the action of extraordinary stimulants (hypoxic hypoxia, hypoxia + hyperoxia, hypodynamia + hyperthermia), animals demonstrate an accumulation of malonic dialdehyde with a simultaneous fall of antiradical activity of the liver tissue. A preliminary introduction to rats of acetylene amine 3,4,5-tris(morpho-linopropynyl)-l-methylpyrazole 103 and also of tocopherol antioxidant and gutumine antihypoxant averts activation of the lipid peroxidation processes. The inhibition of peroxidation with this agent is mediated by stabilization of ly-zosomal and mitochondrial membranes. Unsaturated amines prevent destruction of the organelle membranes provoked by UV irradiation and incubation at 37°C (pH4.7)(78MIl). 

The acetylene aminopyrazole 103 was capable of inhibiting the processes of lipid peroxidation both in the enzymatic and nonenzymatic peroxidation system (76MI2). Finally, 4-[3-(l-methyl-l//-pyrazol-3-yl)-prop-2-ynyl]morpholine hydrochloride 104 was patented as a compound with high hypoxic activity (93MIP1). 

Py rrolostatin is a novel lipid peroxidation inhibitor, which is isolated from Sirepinmyces diresinmyceiiois. Its stnicnire consists of a pyrrole-3-carboxyiic acid v/ith a geranyl group at the 4-posidon. It is readily prepared by applying the Barton-Zard pyrrole synthesis, as shown inEq. 10.33. ... 

Vladimirov, Yu. A. Archakov, A. I. Lipid Peroxidation in Biological Membranes (in Russian), Nauka, Moscow, 1972... 

Balb c mice and Wistar rats were used in the experiments. The administration of single doses of 1, 2 and 2 caused mainly necrotic changes in the liver, measured by GPT and histopathology. The extent of necrosis depended on doses and on time of observation (1-4 days after injections). In shorter time interval (2-4 hrs) 1, 2 and 2 caused depletion of hepatic GSH (even up to 10 % of control). 4 and 5 did not generate necrotic changes. Increased GPT activity was observed after 3 doses of fi. Single doses of 4, 5 and fi mostly increased the level of malondialdehyde (MDA-indicator of lipid peroxidation) in the liver. Repeated injections (3-7) of the investigated compounds enhanced the activity of ALA-D or ALA-S in the liver and caused steatosis. 

Both compounds resulted in statistically significant increase of MDA level in the liver (Fig. 3), which can exemplify lipid peroxidation in the liver. 

Hasan M, Khan NA. 1985. Methyl parathion induced dose related alteration in lipid levels and lipid peroxidation in various regions of rat brain and spinal cord. Indian J Exp Biol 23 141-144. 

Kitada, M., Igarashi, K., Hirose, S. Kitagawa, H. (1979). Inhibition by polyamines of lipid peroxide formation in rat liver microsomes. Biochemical Biophysical Research Communications, 87, 388-92. 

Sandman, G. Boger, P. (1980). Copper mediated lipid peroxidation processes in photosynthetic membranes. Plant Physiology, 66, 797-800. 

Agarwal DK, Seth PK, Gupta PK. 1978. Effect of endosulfan on drug metabolizing enzymes and lipid peroxidation in rat. J Environ Sci Health C13(l) 49-62. 

Narayan S, Bajpai A, Chauhan SS, et al. 1985a. Lipid peroxidation in lung and liver of rats given DDT and endosulfan intratracheally. Bull Environ Contam Toxicol 34 63-67. 

Peroxidation of lipids is another factor which must be considered in the safety evaluation of liposome administration. Smith and coworkers (1983) demonstrated that lipid peroxides can play an important role in liver toxicity. Allen et al. (1984) showed that liposomes protected by an antioxidant caused less MPS impairment than liposomes subjected to mild oxidizing conditions. From the study of Kunimoto et al. (1981) it can be concluded that the level of peroxidation in freshly prepared liposome preparations and those on storage strongly depends both on the phospholipid fatty acid composition and on the head group of the phospholipid. Addition of appropriate antioxidants to liposomes composed of lipids which are liable to peroxidation and designed for use in human studies is therefore necessary. 

Kunimoto, M., Inoue, E., and Nojima, S. (1981). Effect of ferrous ion and ascorbated induced lipid peroxidation on liposomal membranes, Biochim. Biophys. Acta, 646, 169-178. 

Smith, M. T., Thor, H., and Orrenius, S. (1983). The role of lipid peroxidation in the toxicity of foreign compounds to liver cells, Biochem. Pharmacol., 32, 763-764. 

Figure 14-21. Lipid peroxidation. The reaction is initiated by an existing free radical (X ), by light, or by metal ions. Malondialdehyde is only formed by fatty acids with three or more double bonds and is used as a measure of lipid peroxidation together with ethane from the terminal two carbons ofcoB fatty acids and pentane from the terminal five carbons of cb6 fatty acids.

Benzie IFF Lipid peroxidation a review of causes, consequences, measurement and dietary influences. Int J Food Sci Nutr... 

The main function of vitamin E is as a chain-breaking, free radical trapping antioxidant in cell membranes and plasma lipoproteins. It reacts with the lipid peroxide radicals formed by peroxidation of polyunsaturated fatty acids before they can establish a chain reaction. The tocopheroxyl free radical product is relatively unreactive and ultimately forms nonradical compounds. Commonly, the tocopheroxyl radical is... 

Halliwell B, Chirico S Lipid peroxidation its mechanism, measurement, and significance. Am J Clin Nutr 1993 57(5 Suppl) 715S. 

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