Oxidative stress and maternal obesity: feto-placental unit interaction

Abstract

Objective: To determine oxidative stress markers in maternal obesity during pregnancy and to evaluate feto-placental unit interaction, especially predictors of fetal metabolic alterations.

Patients and methods: 40 obese pregnant women (prepregnancy BMI > 30 kg/m²) were compared to 50 control pregnant women. Maternal, cord blood and placenta samples were collected at delivery. Biochemical parameters (total cholesterol and triglycerides) and oxidative stress markers (malondialdehyde, carbonyl proteins, superoxide anion expressed as reduced Nitroblue Tetrazolium, nitric oxide expressed as nitrite, reduced glutathione, catalase, superoxide dismutase) were assayed by biochemical methods.

Results: Maternal, fetal and placental triglyceride levels were increased in obese group compared to control. Maternal malondialdehyde, carbonyl proteins, nitric oxide and superoxide anion levels were high while reduced glutathione concentrations and superoxide dismutase activity were low in obesity. In the placenta and in newborns of these obese mothers, variations of redox balance were also observed indicating high oxidative stress. Maternal and placental interaction constituted a strong predictor of fetal redox variations in obese pregnancies.

Discussion: Maternal obesity compromised placental metabolism and antioxidant status which strongly impacted fetal redox balance. Oxidative stress may be one of the key downstream mediators that initiate programming of the offspring.

Conclusion: Maternal obesity is associated with metabolic alterations and dysregulation of redox balance in the mother-placenta - fetus unit. These perturbations could lead to maternal and fetal complications and should be carefully considered.

Keywords: Mother; Newborn; Obesity; Oxidative stress; Placenta; Pregnancy.