Dietary supplementation with polyunsaturated fatty acid during pregnancy modulates DNA methylation at <i>IGF2/H19</i> imprinted genes and growth of infants

다국어 초록 (Multilingual Abstract)

<P>Epigenetic regulation of imprinted genes is regarded as a highly plausible explanation for linking dietary exposures in early life with the onset of diseases during childhood and adulthood. We sought to test whether prenatal dietary supplementation with docosahexaenoic acid (DHA) during pregnancy may modulate epigenetic states at birth. This study was based on a randomized intervention trial conducted in Mexican pregnant women supplemented daily with 400 mg of DHA or a placebo from gestation <I>week 18–22</I> to parturition. We applied quantitative profiling of DNA methylation states at <I>IGF2</I> promoter 3 (<I>IGF2</I> P3), <I>IGF2</I> differentially methylated region (DMR), and <I>H19</I> DMR in cord blood mononuclear cells of the DHA-supplemented group (<I>n</I> = 131) and the control group (<I>n</I> = 130). In stratified analyses, DNA methylation levels in <I>IGF2</I> P3 were significantly higher in the DHA group than the control group in preterm infants (<I>P</I> = 0.04). We also observed a positive association between DNA methylation levels and maternal body mass index; <I>IGF2</I> DMR methylation was higher in the DHA group than the control group in infants of overweight mothers (<I>P</I> = 0.03). In addition, at <I>H19</I> DMR, methylation levels were significantly lower in the DHA group than the control group in infants of normal weight mothers (<I>P</I> = 0.01). Finally, methylation levels at <I>IGF2/H19</I> imprinted regions were associated with maternal BMI. These findings suggest that epigenetic mechanisms may be modulated by DHA, with potential impacts on child growth and development.</P>