Blood lipid peroxides

Ravikumar, P. and Anuradha, C.V. (1 999) Effect of fenugreek seeds on blood lipid peroxidation and antioxidants in diabetic rats. Phytotherapy Research 1 3(3), 1 97-201. 

Gaal, T., Mezes, M., Miskucza, O. Ribiczey-Szabo, P. 1993. Effect of fasting on blood lipid peroxidation parameters of sheep. Res. Vet. Sci., 55, 104-107. 

Daily administration of curcuminoids (0.5 g) to healthy human volunteers produced a 33% reduction in blood lipid peroxide levels (Soni and Kuttan 1992). This was accompanied by an increase in HDL cholesterol and a decrease in total serum cholesterol as a result of curcumin administration (500 mg/day for 7 days) (Quiles etal. 2002). The reduction in serum lipid peroxides and cholesterol suggests the potential of curcumin against arterial diseases. Supplementation with turmeric extract reduced oxidative stress and attenuated the development of atherosclerotic fatty streaks in rabbits fed on a high-cholesterol diet (Quiles etal. 2002). 

Oxidation of LDL plays an important role in the development of atherosclerosis. Turmeric extract decreased the susceptibility of LDL to lipid peroxidation, thus suggesting its value in the management of cardiovascular disease (Ramirez-Tortosa et al. 1999). In healthy hiunans, the daily intake of 200 mg of turmeric extract resulted in a decrease in total blood lipid peroxides as well as in HDL- and LDL-lipid peroxidation (Miquel et al. 2002). The beneficial influence of dietary curciunin on the susceptibility of LDL to oxidation was examined in an animal study. Dietary curcumin significantly inhibited the in vivo iron-induced LDL oxidation as well as copper-induced oxidation of LDL in vitro (Manjunatha and Srinivasan 2006). 

Selley et al. (1992) have recently employed gas chromatography combined with mass spectrometric detection to determine levels of the cytotoxic monounsaturated aldehyde 4-hydroxy-/7 t-2-nonenal in the blood plasma of healthy human subjects, and patients with rheumatoid and osteoarthritis. Intriguingly, this lipid peroxidation end-product is present at a concentration ofc. lx 10 mol/dm in healthy and osteoarthritic human plasma samples (but significantly elevated in those collected from rheumatoid arthritis patients). Although at least some of this could originate from the oxidative degradation of PUFAs invm, there may be a relationship existing between these levels and the frequency of thermally/... 

Frei, B., Stocker, R. and Ames, B.N. (1988). Antioxidant defences and lipid peroxidation in human blood plasma. Proc. Natl Acad. Sci. USA 85, 9748-9752. 

Duthie, G.G., Robertson, J.D., Maughan, RJ. and Mortice, P.C. (1990). Blood antioxidant status and erythrocyte lipid peroxidation following distance running. Arch. Biochem. Biophys. 282, 73-83. 

Cavaliere, F., Clemente, A., Vagnoni, S., Carducci, P., Aureli, V. and Lippa, S. (1989). Products of lipid peroxidation in the blood and respiratory secretions in patients with acute respiratory diseases. Minerva Anestesiol. 55, 283-286. 

Hepatic reperfusion injury is not a phenomenon connected solely to liver transplantation but also to situations of prolonged hypoperfusion of the host s own liver. Examples of this occurrence are hypovolemic shock and acute cardiovascular injur) (heart attack). As a result of such cessation and then reintroduction of blood flow, the liver is damaged such that centrilobular necrosis occurs and elevated levels of liver enzymes in the serum can be detected. Particularly because of the involvement of other organs, the interpretation of the role of free radicals in ischaemic hepatitis from this clinical data is very difficult. The involvement of free radicals in the overall phenomenon of hypovolemic shock has been discussed recently by Redl et al. (1993). More specifically. Poll (1993) has reported preliminary data on markers of free-radical production during ischaemic hepatitis. These markers mostly concerned indices of lipid peroxidation in the serum and also in the erythrocytes of affected subjects, and a correlation was seen with the extent of liver injury. The mechanisms of free-radical damage in this model will be difficult to determine in the clinical setting, but the similarity to the situation with transplanted liver surest that the above discussion of the role of XO activation, Kupffer cell activation and induction of an acute inflammatory response would be also relevant here. It will be important to establish whether oxidative stress is important in the pathogenesis of ischaemic hepatitis and in the problems of liver transplantation discussed above, since it would surest that antioxidant therapy could be of real benefit. 

As the superoxide radical is a precursor of the other reactive oxygen species and interacts with blood plasma components under physiological and pathological conditions as well, systems related to its generation are biologically relevant. It should be noted, however, that with respect to the initiation of lipid peroxidation as one of the main causes of oxidative cell damage, its own reactivity is very weak and that only in protonized form is its toxicity comparable to that of lipid peroxyl radicals [18]. 

It should be mentioned that the inhibition of superoxide overproduction and lipid peroxidation by lipoic acid has been recently shown in animal models of diabetes mellitus. The administration of LA to streptozotocin-diabetic rats suppressed the formation of lipid peroxidation products [213], In another study the supplementation of glucose-fed rats with lipoic acid suppressed aorta superoxide overproduction as well as an increase in blood pressure and insulin resistance [214]. 

Thus, the mechanism of MT antioxidant activity might be connected with the possible antioxidant effect of zinc. Zinc is a nontransition metal and therefore, its participation in redox processes is not really expected. The simplest mechanism of zinc antioxidant activity is the competition with transition metal ions capable of initiating free radical-mediated processes. For example, it has recently been shown [342] that zinc inhibited copper- and iron-initiated liposomal peroxidation but had no effect on peroxidative processes initiated by free radicals and peroxynitrite. These findings contradict the earlier results obtained by Coassin et al. [343] who found no inhibitory effects of zinc on microsomal lipid peroxidation in contrast to the inhibitory effects of manganese and cobalt. Yeomans et al. [344] showed that the zinc-histidine complex is able to inhibit copper-induced LDL oxidation, but the antioxidant effect of this complex obviously depended on histidine and not zinc because zinc sulfate was ineffective. We proposed another mode of possible antioxidant effect of zinc [345], It has been found that Zn and Mg aspartates inhibited oxygen radical production by xanthine oxidase, NADPH oxidase, and human blood leukocytes. The antioxidant effect of these salts supposedly was a consequence of the acceleration of spontaneous superoxide dismutation due to increasing medium acidity. 

Free radicals are supposed to have a significant role in the progression of acute pancreatitis. The involvement of free radicals was firstly demonstrated in many animal models [355,356], Later on, it has been shown that the levels of superoxide and lipid peroxides increased in the blood from patients with acute pancreatitis [357], Rahman et al. [358] found enhanced urinary nitrite excretion in patients with severe acute pacreatitis. It was suggested that this fact is not simply a reflection of systemic inflammation but probably a consequence of the endotoxin-mediated upregulation of inducible NO synthase. 

Nachtomi E, Alumot E. 1972. Comparison of ethylene dibromide and carbon tetrachloride toxicity in rats and chicks Blood and liver levels lipid peroxidation. Exp Mol Pathol 16 71-78. 

Minor chromosomal abnormalities Inhibition of intracellular hydrolytic enzymes of alveolar macrophages increased fraction of polymorphonuclear leukocytes Alterations in blood, including red-cell membrane and enzyme changes and increased serum vitamin E and lipid peroxides Decreased lung DNA synthesis Decreased electric response of specific areas of brain with evoked-response technique... 

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