Association between maternal diet, smoking, and the placenta MTHFR 677C/T genotype and global placental DNA methylation.

INTRODUCTION: The placenta provides nutrients to the fetus, and it has protective effects against harmful substances. Unhealthy maternal diets and toxic agents might increase free radical (FR) production. Elevated FR levels are associated with a high risk of oxidative stress, which may cause DNA damage. DNA might be oxidized in the placenta, occasionally affecting its methylation profile due to 8-hidroxy-2'-deoxyguanosine formation. METHODS: This study assessed 130 mothers and their children. The maternal's nutritional patterns were determined using the Food Frequency Questionnaire. Information on smoking and alcohol consumption was collected during the medical examination. Data on placental DNA were obtained to determine the MTHFR 677C/T genotype and the proportion of placental DNA methylation (pDNAm). RESULTS: Consumption of vitamins and folic acid was above 85%. The pDNAm was found to be correlated with gestational age and coffee intake. Mothers with a smoking history had a low pDNAm. Placentas with the TT genotype had a higher but not significant pDNAm. In the placentas with the CC/CT genotype, the pDNAm was positively associated with carbohydrate and biotin intake. However, the TT genotype was negatively associated with folate and vegetable intake. DISCUSSION: The pDNAm was positively associated with coffee intake, but not with macro-, and micronutrient intake. However, it was negatively associated with cigarette smoking. The placentas with the CC/CT genotype had a lower pDNAm than those with the TT genotype. In the placentas with the CC/CT or TT genotype, methylation was positively, and negatively associated with micro- or macronutrients, respectively.

Maternal obesity increases oxidative stress in the newborn.

OBJECTIVE: Obesity before pregnancy is associated with a greater risk for the offspring to develop obesity and diabetes in childhood and adulthood. The aim of the present study was to determine the association between maternal overweight or obesity before pregnancy and newborn oxidative stress (OS). METHODS: Seventy-two mother-child pairs were divided according to the pre-gestational body mass index (BMI) of the mothers as follows: eutrophic (n = 21), overweight (n = 32), and obese (n = 19). Malondialdehyde (MDA) and nitric oxide (NO) were measured in the plasma of a blood sample from the newborn's umbilical cord. RESULTS: The MDA levels of newborns increased with maternal BMI (P = 0.001), as did the levels of NO (P = 0.019). There was a direct correlation between MDA and NO levels in each of the three groups (eutrophic: R(2) = 0.59, P < 0.001; overweight: R(2) = 0.45, P < 0.001; and obese: R(2) = 0.26, P = 0.024). CONCLUSIONS: Maternal overweight and obesity before pregnancy are associated with increased OS in the offspring.