Increased susceptibility to undergo lipid peroxidation of chylomicrons and low-density lipoprotein in celiac disease.

ABSTRACT

Gastrointestinal injury involves oxidative damage as the result of oxygen-derived free radicals which are formed during the inflammatory reactions. Chylomicrons which are synthesized by the intestine can thus be exposed to lipid peroxidation in celiac disease. Similarly, low-density lipoprotein (LDL) propensity to oxidation may be enhanced as a result of a direct or indirect effect of the oxidative process. To resolve these possibilities, plasma chylomicrons and LDL were isolated from a patient with celiac disease and from a control healthy subject before and 3 h after a fat-rich meal, and their propensity to copper-induced lipid peroxidation was then analyzed. The patient's chylomicrons, its LDL that was obtained before the fat-rich meal and its LDL that was obtained after the meal demonstrated 220, 39 and 48% elevation in their content of thiobarbituric-acid-reactive substances in comparison with the control lipoproteins. After a complete recovery of the patient's intestine, the susceptibility of the patient lipoproteins to in vitro oxidation returned toward normal levels. In the patient LDL fraction (obtained either before or after the fat-rich meal), but not in the patient's chylomicrons, the carotenoid content was reduced by 70%, vitamin E by 45%, and the LDL content of arachidonic acid was increased by 70% in comparison with the control lipoproteins. On recovery of the patient and return of the intestine to its normal morphology, normalization of all of these constituents was achieved.