The oxidation of
lipids is important in many pathological conditions and lipid peroxidation products such as
4-hydroxynonenal (HNE) and other
aldehydes are commonly measured as
biomarkers of oxidative stress. However, it is often useful to
complement this with analysis of the original oxidized
phospholipid. Electrospray mass spectrometry (ESMS) provides an informative method for detecting oxidative alterations to
phospholipids, and has been used to investigate oxidative damage to cells, and
low-density lipoprotein, as well as for the analysis of oxidized
phosphatidylcholines present in
atherosclerotic plaque material. There is increasing evidence that intact oxidized
phospholipids have
biological effects; in particular, oxidation products of 1-palmitoyl-2-arachidonoyl-sn-glycerophosphocholine (PAPC) have been found to cause inflammatory responses, which could be potentially important in the progression of
atherosclerosis. The effects of chlorohydrin derivatives of
lipids have been much less studied, but it is clear that
free fatty acid chlorohydrins and
phosphatidylcholine chlorohydrins are toxic to cells at concentrations above 10 micromolar, a range comparable to that of HNE and oxidized PAPC. There is some evidence that
chlorohydrins have
biological effects that may be relevant to
atherosclerosis, but further work is needed to elucidate their pro-inflammatory properties, and to understand the mechanisms and balance of
biological effects that could result from oxidation of
complex mixtures of
lipids in a pathophysiological situation.