Increase in fragmented phosphatidylcholine in blood plasma by oxidative stress

Bettina Frey,Renate Haupt,Sonja Alms,Gerhard Holzmann,Thomas König,Hartmut Kern,Wolfgang Kox,Bernd Rüstow,Michael Schlame

doi:10.1016/s0022-2275(20)32021-6

Abstract

Oxidatively modified phospholipids with fragmented acyl chains have attracted much interest because of their proinflammatory activity and their potential involvement in atherosclerosis. They can be formed in vitro by free radical treatment of unsaturated phospholipids but it is not known under which conditions they accumulate in vivo. We assayed one species of fragmented phosphatidylcholine (PC) in human blood plasma by high performance liquid chromatography after precolumn derivatization with chloromethylanthracene. Structural analysis suggested that fragmented PC was a diacyl species with a palmitoyl group and a short oxidized residue, which most likely had four carbons. The concentration of fragmented PC was higher in elderly individuals with coronary heart disease than in young healthy controls. Smoking one cigarette acutely increased the concentration of fragmented PC in healthy adults. Fragmented PC also increased in the reperfusion period after treatment with cardiopulmonary bypass. The increase coincided with a surge of circulating neutrophils. In rats, the plasma concentration of fragmented PC was elevated by vitamin E deficiency and exposure to high oxygen.The data demonstrate that fragmented PC increases in blood plasma in response to various forms of oxidative stress.

Highlights

Modified phospholipids with fragmented acyl chains have attracted much interest because of their proinflammatory activity and their potential involvement in atherosclerosis
Reactive oxygen species can induce peroxidation of lipids, a process that has been implicated in atherosclerosis [1,2,3], inflammation [1, 4], aging [5] and other diseases associated with oxidative stress [6, 7]
Fragmented phospholipids have been detected by bioassay in the blood plasma of hamsters exposed to cigarette smoke [21]

Summary

Introduction

Modified phospholipids with fragmented acyl chains have attracted much interest because of their proinflammatory activity and their potential involvement in atherosclerosis. The chemical structure of this activity is not known; several synthetic PCs with short acyl chains had stimulatory effects on neutrophils [16], platelets [19, 20], and monocytes [20]. Despite this evidence, it has been difficult to establish the presence of fragmented phospholipids in vivo. We developed a technique to quantify fragmented PC in blood plasma by high performance liquid chromatography (HPLC) with precolumn derivatization [22] This technique prevents assessment of bioactivity, it enabled us to determine the chemical concentration of one fragmented phospholipid species.

Methods

Results

Conclusion