Fig. 4

Mechanisms of oxidative damage to LDL-c and HDL-c lipoproteins of newborns from women with preeclampsia. Both lipoproteins have damage to lipids; there are molecular products resulting from lipoperoxidation, such as conjugated dienes (mild damage) (a), lipohydroperoxides (moderate damage) (b), and malondialdehyde (severe damage (c). Lipohydroperoxides can be hydrolysed by the PON-I enzyme. When the activity of this enzyme decreases (d), malondialdehyde levels increase. Additionally, this process can damage proteins through the formation of adducts that induce carbonyl groups (f). Other protein oxidation indicators are through the formation of orthoquinones that can reduce the NBT compound and/or by the formation of dityrosines (e). In newborns from women with preeclampsia, these last two mechanisms of damage do not occur, probably due to the increase in total systemic antioxidant capacity. Non-protein antioxidants, such as uric acid, ascorbic acid, glutathione, and alpha-tocopherol, and protein antioxidants, such as bilirubin and albumin, protect against damage (g)