HISTOLOGICAL-FINDINGS AND EVIDENCE OF LIPID CONJUGATED DIENES AND MALONYLDIALDEHYDE IN HUMAN FETAL AORTAS

Recent evidence strongly suggests that peroxidative modification of li pids may play a significant role in atherogenesis. In our present rese arch, we investigated if the oxidative stress mediated by oxygen free radicals was a pathophysiologic condition that occurred in the early s tages of human development. Thus the aim of this research was to exami ne lipid peroxidation in human fetal aortas. Human fetal aortas and pr oximal iliac arteries (n = 8) were obtained from fetuses aged 7 +/- 2 months, immediately after autopsy. Lipids from the initial fatty strea k lesions (LFS) and the vessels uninvolved (LUV) were extracted by the chloroform/methanol method. Lipid peroxidation levels were measured b y two different methods: determination of lipid conjugate dienes (the spectrum trend was recorded from 320 to 200 nm with a spectrophotomete r) and malonyldialdehyde (MDA) content (TBA method). We observed that lipid conjugated dienes were present in LFS, but not in LUV, with a ch aracteristic absorption peak at 233 nm. In addition, MDA levels were s ignificantly higher when the LFS = 3.85 +/- 0.91 nmol than when the LU V = 0.41 +/- 0.12 nmol (p < 0.001 versus LUV). The presence of lipid p eroxidation in our samples could be mediated by free radical productio n in the first stages of human development. Thus these data suggest th at LFS peroxidation mediated by free radicals occurs in the vascular c irculation in the early stages of human development. This could influe nce the progression of vascular damage and atherosclerotic disease.