Lipoxins inflammation resolution

Serhan C. N. (2005a). Lipoxins and aspirin-triggered 15-epi-lipoxins are the first lipid mediators of endogenous anti-inflammation and resolution. Prostaglandins Leukot. Essent. Fatty Acids 73 141-162. 

Lipoxins are a series of anti-inflammatory, nonclassic eicosanoids ( nonclassic in the sense that they are synthesised by oxygenation of 20-carbon fatty acids other than the classic eicosanoids) whose appearance in inflammation normally signals its resolution. At present two hpoxins have been identified lipoxin A4 (LXA4) and lipoxin B4 (LXB4). 

Fig. 1 Proposed homeostatic regulation of inflammation in effective host defence. The initial phase of inflammation is initiated by a host of pro-inflammatory cytokines and eicosanoids which subsequently become diminished with time, and are coupled with the likely activation of anti-inflammatory and pro-resolution mediators, including the lipoxins, resolvins and protectins. Typically, IL 13 up-regulates 15-LO gene expression of human blood monocytes for example (Nassar et al. 1994). The associated increase in enzyme activity results in an increase in LX generation which promotes the resolution phase of inflammation. IL, interleukin TNF-a, tumour necrosis factor-a MCP-1, monocyte chemotactic protein-1 RANTES, regulated upon activation, normal T-cell expressed and secreted TGF i, transforming growth factor...

This chapter summarizes recent findings involving the formation and biological roles of several new types of polyunsaturated anti-inflammatory and pro-resolving lipid mediators [1], such as lipoxins, resolvins, protectins, and maresins (MaR). These molecules are able to dampen the inflammatory response, promote the resolution of inflammation, and exhibit other beneficial actions at inflammatory sites [2-4]. 

El Kebir D., Jozsef L., Khreiss T., Pan W., Petasis N. A., Serhan C. N., Filep J. G. 2007. Aspirin-triggered lipoxins override the apoptosis-delaying action of serum amyloid A in human neutrophils A novel mechanism for resolution of inflammation, Immunology. 179(l) 616-622. 

Fierro, IM and Serhan, CN (2001) Mechanisms in anti-inflammation and resolution the role of lipoxins and aspirin-triggered lipoxins. Braz J Med Biol Res, 34, 555-566. 

Serhan, CN (2002) Lipoxins and aspirin-triggered 15-epi-lipoxin biosynthesis an update and role in anti-inflammation and pro-resolution. Prostaglandins Other Lipid Mediat, 68-69, 433 55. 

Serhan, CN and Chiang, N (2002) Lipid-derived mediators in endogenous anti-inflammation and resolution lipoxins and aspirin-triggered 15-epi-lipoxins. ScientificWorldJoumal, 2, 169-204. 

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