RESUMO
PURPOSE: Dietary supplementation with probiotics during pregnancy has been suggested to decrease the risk for obesity in women after delivery and to minimize excessive weight gain in their children. Epigenetic DNA methylation has been proposed to impact on gene activity, thereby providing a plausible molecular mechanism for a broad range of biological processes and diseases. This pilot study aimed to evaluate whether probiotic supplementation during pregnancy could modify the DNA methylation status of the promoters of obesity and weight gain-related genes in mothers and their children. METHODS: A sample of 15 pregnant women was taken from a prospective, randomized mother and infant nutrition and probiotic study. Seven women received the probiotic supplementation and eight served as controls. The women's and their children's DNA methylation status of obesity (623 genes) and weight gain-related (433) gene promoters were analyzed from blood samples at the mean of 9.8 months (range 6.1-12.7 months) postpartum. RESULTS: Probiotic supplementation led to significantly decreased levels of DNA methylation in 37 gene promoters and increased levels of DNA methylation in one gene promoter in women. In their children, 68 gene promoters were significantly affected consistently with a lower level of DNA methylation in the probiotic group. CONCLUSIONS: On the basis of our pilot study, we suggest that probiotic supplementation during pregnancy may affect the DNA methylation status of certain promoters of obesity and weight gain-related genes both in mothers and their children, thereby providing a potential mechanism for long-lasting health effects.