10,12-Octadecadienoic acid

Henry DY, Gueritte-Voegelein F, Insel PA, Ferry N, Bouguet J, Potier P, Hanoune J. Isolation and characterization of 9-hydroxy- 10-trans,12-cis-octadecadienoic acid, a novel regulator of platelet adenylate cyclase from Glechoma hederacea L. Labiatae. Eur J Biochem 1987 170 389-394. 

Hydroxy-10,12-octadecadienoic acid, which is formed by the reduction of 9-HPODE, was identified in the erythrocyte membrane phospholipid of diabetic patients [83]. It was suggested that this compound was formed as a result of glucose-induced oxidative stress in the reaction of hydroxyl radicals with linoleic acid. 

FIGURE 25.4 Mechanism of conversion of 13-hydroperoxy-9,ll-octadecadienoic acid (13-HPODE) into 4-hydroxynonenal (4-HNE). (Adapted from C Schneider, KA Tallman, NA Porter, AR Brash. J Biol Chem 276 20831-20838, 2001. With permission.)... 

It follows from the above that MPO may catalyze the formation of chlorinated products in media containing chloride ions. Recently, Hazen et al. [172] have shown that the same enzyme catalyzes lipid peroxidation and protein nitration in media containing physiologically relevant levels of nitrite ions. It was found that the interaction of activated monocytes with LDL in the presence of nitrite ions resulted in the nitration of apolipoprotein B-100 tyrosine residues and the generation of lipid peroxidation products 9-hydroxy-10,12-octadecadienoate and 9-hydroxy-10,12-octadecadienoic acid. In this case there might be two mechanisms of MPO catalytic activity. At low rates of nitric oxide flux, the process was inhibited by catalase and MPO inhibitors but not SOD, suggesting the MPO initiation. 

Inhibition and stimulation of LOX activity occurs as a rule by a free radical mechanism. Riendeau et al. [8] showed that hydroperoxide activation of 5-LOX is product-specific and can be stimulated by 5-HPETE and hydrogen peroxide. NADPH, FAD, Fe2+ ions, and Fe3+(EDTA) complex markedly increased the formation of oxidized products while NADH and 5-HETE were inhibitory. Jones et al. [9] also demonstrated that another hydroperoxide 13(5)-hydroperoxy-9,ll( , Z)-octadecadienoic acid (13-HPOD) (formed by the oxidation of linoleic acid by soybean LOX) activated the inactive ferrous form of the enzyme. These authors suggested that 13-HPOD attached to LOX and affected its activation through the formation of a protein radical. Werz et al. [10] showed that reactive oxygen species produced by xanthine oxidase, granulocytes, or mitochondria activated 5-LOX in the Epstein Barr virus-transformed B-lymphocytes. 

Dodecanoic acid Tetradecanoic acid Hexadecanoic acid Octadecanoic acid 9-Octadeceanoic acid 9,12-Octadecadienoic acid 9,12,15-Octadecatrienoic acid... 

Octacyanide ion, 17 26 Octacyanotungstate(IV), 7 578t 5,6-Octadecadienoic acid, physical properties, 5 33t... 

Systematic names cw-9-Octadecenoic acid cis.cis.-9,12-Octadecadienoic acid... 

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