Les biomarqueurs de la peroxydation lipidique

UMR 585 Inserm/Insa de Lyon Laboratoire de physiopathologie des lipides et membranes Bât. Louis Pasteur 69621 Villeurbanne, France 04 72 43 85 24

^* michel.guichardant@insa-lyon.fr

Abstract

Different biomarkers related to lipid peroxidation are available to assess an oxidative stress. They are more or less specific and sensitive. For instance malondialdehyde (MDA) or conjugated diene are easily measured in different matrix. Their measurements provide only a rough indication assessing an oxidative stress. But sometimes information is wrong due to artefacts. Some markers such as isoprostanes are specific of arachidonic acid only, and they require expensive equipment such as GC-MS/MS. They are mainly dedicated to clinical investigation. We present here new markers of oxidative stress which allow to discriminate between the oxidation of polyunsaturated fatty acid families. They are 4-hydroxynonenal (4-HNE) and 4-hydroxy-hexenal (4-HHE) which represent the peroxidation of the n-6 and n-3 polyunsaturated fatty acids, respectively and 4-hydroxy-dodecadienal (4-HDDE) which derives from the breakdown of 12-HpETE and mainly reflects the 12 lipoxygenation of arachidonic acid. Those markers can be easily measured with a high sensitivity by GC-MS in plasma. Their urinary carboxylic oxidized end-products, namely 4-HNA, 4-HHA and 4-HDDA may also be measured by GC-MS. The choice between these different biomarkers is not easy. It depends on which information is required.