The Role and Modulation of the Oxidative Balance in Pregnancy

Abstract

Oxidative processes exert a fundamental regulatory function during pregnancy. It depends on the influence of oxygen, nitric oxide, reactive oxygen species and reactive nitrogen species metabolic pathways upon the vascular changes in the maternal organism, as well as on the regulation of uterine and cervical tone throughout gestation and delivery. These functions are strictly linked with the mediators of the inflammatory pathway. At the beginning of pregnancy, when a certain grade of inflammatory change is necessary to the trophoblast invasion of maternal tissue, the activation of the process by nitric oxide and reactive nitrogen species is welcome. Indeed, these products modulate the metalloproteinases, which are responsible for the remodelling of uterine extracellular matrix. At this stage estrogens are involved as well in the regulation of the delicate balance of pro-oxidant and anti-oxidant effects. Furthermore, reactive oxygen and nitrogen species appear to play an important role both in normal and pathologic embryogenesis. During advanced pregnancy, a derangement of the oxidative balance can lead to the improper activation of inflammatory changes, thus triggering premature labour as well as other complications, such as foetal growth restriction and preeclampsia. Although a number of pro- and anti-oxidant agents are available to influence the above-mentioned processes, there is no way to adequately measure the oxidative needs in single cases, in order to modulate the oxidative balance in clinical practice. Pharmacological research should be addressed to the development of new drugs, as well as to selective methods of delivery to the gestational tissues.

Proteomic analysis of porcine endometrial tissue during peri-implantation period reveals altered protein abundance

“…Acute phase proteins are synthesized in mammals at the onset of inflammation regardless of how the inflammation is caused [47]. Pregnancy has been reported to be associated with inflammation [48,49] and oxidative stress [50][51][52]. The expression of ceruloplasmin, a multifunctional copper-containing protein, was higher on Day 12 than Day 9 irrespective of pregnancy status with the highest levels in the pregnant endometrium on Day 12.…”

Nitric oxide metabolite levels and assessment of cervical length in the prediction of preterm delivery among women undergoing symptomatic preterm labor

“…Although the source of this local NOx production is unknown, both infiltrating inflammatory cells and cells of the uterine cervix may be responsible. Given that NOx can activate matrix metalloproteinases [11,12] and induce apoptotic cell death [13,14], overproduction of NOx could be involved in cervical ripening, fragility of membranes, and subsequent premature delivery. In addition, elevated plasma NOx levels have been reported to show an association with PTL and PTD [15].…”

Effect of Antioxidants and Nitric Oxide on Activity of Peritoneal Macrophages in Albino Rats during Normal Pregnancy

“…Phagocytosis activation in normal pregnancy can be explained, on the one hand, by the oxidative damage to erythrocyte membranes and intensive erythropoiesis under these conditions; on the other hand, by changes in hormone concentrations, and composition, topography, and metabolism of macrophage membrane phospholipids [2], which produce a stimulating effect on the cells. In group 1 rats, addition of trolox and SOD to the incubation medium did not affect phagocytosis (Table 1).…”