A-chlorofatty aldehyde

The characterization of the product of RCS targeting of plasmalogens led to several methods that were developed to both purify and quantify a-halofatty aldehyde. For example, thin-layer chromatography with silica gel G as a solid phase and petroleum ether/ethyl ether/acetic acid (90/10/1) separates a-chlorofatty aldehydes (/f =0.46) and a-bromofatty aldehydes (Rf= 0.58) (Albert et al. 2001, 2002). The confirmation of the structure of 2-chlorohexadecanal and 2-bromohexadecanal using GC-MS following derivatization to its pentafluorobenzyl oxime also proved to be an extremely... 

FIGURE 4.3 Metabolism of a-chlorofatty aldehyde. a-Chlorofatty aldehyde (a-ClFALD) a-chlorofatty alcohol (a-ClFOH) a-chlorofatty acid (a-ClFA) a-chlorodicarboxylic acid (a-ClDCA). 

While 2-chlorohexadecanal is produced in both atherosclerotic lesions and infarcted myocardium, it remains to be seen whether this aldehyde gives rise to chlorinated lipid metabolites as well as the putative incorporation of chlorinated aliphatic groups into complex lipids including triglycerides, phospholipids, and cholesteryl esters. Furthermore, these metabolites need to be assessed in experiments designed to demonstrate biological effects of a-chlorofatty aldehyde. 

While significant studies have focused on the biological roles of a-chlorofatty aldehyde, the roles of its metabolites need to be assessed, and the potential roles assigned to a-chlorofatty aldehyde that are actually mediated by its metabolites should be considered. Since both 2-chlorohexadecanal and 2-chlorohexadecanoic acid increase endothelial COX-2 levels, it is possible that 2-chlorohexadecanal does not directly elicit COX-2 expression, but rather its fatty add metabolite may be the mediator of this pathway (Anbukumar et al. 2010 Messner et al. 2008). It should be noted that the role of metabolites of both a-bromofatty aldehyde and a-iodofatty aldehyde remain to be examined. 

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