Detection of 4-hydroxynonenal (HNE) as a physiological component in human plasma.

4-Hydroxynonenal (HNE) is a major aldehydic product formed by peroxidation of omega 6-unsaturated fatty acids and is regarded as a specific marker of lipid peroxidation. In this paper we demonstrate that there is a physiological steady-state concentration of HNE in human venous blood plasma. For the quantitative determination of HNE a modified version of an existing, but tedious and time-consuming HPLC method was developed. The extraction of aldehydic hydrazones from plasma was performed using an Extrelut column and the separation step by thin-layer chromatography was replaced by column chromatography on silica gel. The concentration of HNE in human blood plasma was in the same range as the concentration that was found to inhibit the proliferation of cells of the peripheral tissues, i.e., endothelial cells and fibroblasts in vitro. In an experiment with reduced peripheral blood flow a temporary significant increase of HNE was observed during reperfusion. It was concluded that lipid peroxidation occurs in peripheral tissues of humans following temporary congestion of venous blood flow.