Arachidonate cascade

In cell free systems or isolated cells, some enzymes of the arachidonate cascade can also recognize AEA and 2-AG as substrates, thereby producing the corresponding lipoxygenase and cyclooxygenase-2 derivatives. However, these metabolites have not yet been isolated from tissues and their biological relevance is still unknown. 

Okhura. Effects of sho-saiko-to on cytokine cascade and arachidonic cascade. Adv Exp Med Biol 1992 319 309-317. 

Some (Kis et ah, 1999 Verrotti et ah, 1999), but not all (Tanindi et ah, 1996), studies show that DVP may prolong bleeding time in pediatric patients. The mechanism of the DVP-induced platelet dysfunction has not yet been elucidated. Inhibition of the secondary phase of platelet aggregation (Verrotti et ah, 1999) and the platelet arachidonate cascade (Kis et ah, 1999) have been postulated as potential mechanisms contributing to the platelet-function alterations caused by DVP. Drug discontinuation may not be necessary (Kis et ah, 1999). 

The fatty acid-like leukotrienes derived from the addition of glutathione to products of the lipoxygenase branch of the arachidonic cascade are closely associated with manifestations of asthma. Many compounds designed to antagonize leukotrienes at the receptor level incorporate long alkyl chains to mimic the leukotrienes backbone in addition to the sulfur-containing moieties that stand in for glutathione. The reaction... 

Lipid peroxidation has often been regarded simply as an undesirable side reaction, but it is also a normal part of metabolism. Initiated by enzymatically generated radicals, peroxidation occurs as specific metabolic pathways, such as the arachidonate cascade, which leads to a variety of local hormones and other substances (Eq. 21-16).254 2563... 

Prostaglandins have been implicated both in the induction of inflammation and in its relief. In inflammation small blood vessels become dilated, and fluid and proteins leak into the interstitial spaces to produce the characteristic swelling (edema). Many polymorphonuclear leukocytes attracted by chemotactic factors that include LTB4309 (Chapter 19) migrate into the inflamed area, engulfing dead tissue and bacteria. In this process lysosomes of the leukocytes release phospholipase A, which hydrolyzes phospholipids and initiates the arachidonate cascade. The leukotrienes that are formed promote the inflammatory response. However, cAMP can suppress inflammation, and PGE2 has a similar effect. Indeed, E prostaglandins, when inhaled in small amounts, relieve asthma. 

Roland I., de Leval X., Evrard B., Pirotte B., Dogne J. M., and Delattre L. (2004). Modulation of the arachidonic cascade with omega 3 fatty acids or analogues Potential therapeutic benefits. Mini-Rev. Medicin. Chem. 4 659-668. 

The precise mode of action is unknown. Sulfasalazine has an immunomodulatory effect as well as an antibacterial action. It also has influences on the arachidonic cascade and alters the activity of enzymes involved in the inflammatory process. 

Monterrey-Rodrigues et al., 2002). Because bromelian in papaya and pineapple modulates the arachidonate cascade, INR rates are also increased with concomitant use of warfarin (Shaw et al., 1997). In contrast, the vitamin K in a variety of green vegetables, particularly broccoli, in large amounts can act as an antagonist to the effects of anti-coagulant therapy (D Arcy, 1993) in warfarin overdose, vitamin K is used to normalize the INR. 

Maccarrone M, Salvati S, Bari M, Finazzi-Agro A (2000b) Anandamide and 2-arachidonoyl-glycerol inhibit fatty acid amide hydrolase by activating the lipoxygenase pathway of the arachidonate cascade. Biochem Biophys Res Commun 278 576-583... 

The arachidonate cascade includes the COX pathway to form prostanoids and the lipoxygenase (LOX) pathway to generate several oxygenated fatty acids, collectively called eicosanoids. While the exact mechanism remains unknown, it has been shown that eicosanoids play a dual role in regulating both cell survival and apoptosis in various types of cells [81]. One recent study, for example, demonstrated that arachidonic acid metabolites are involved in the regulation of apoptosis in human polymorphonuclear neutrophil granulocytes [82],... 

The release of arachidonafe and initiation of the arachidonate cascade is induced by hormones, various inflammatory and immunological stimuli, and even mechanical agitation. Tissues do not all behave the same in response to the arachidonate cascade.2 ... 

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