Docosahexaenoic Acid (DHA) Supplementation Benefits Pregnancy Complicated with Gestational Diabetes Mellitus (GDM)

Abstract

GDM, characterized by an alteration of glucose regulation which is first detected during pregnancy, is associated with elevated blood glucose, insulin resistance, pro‐inflammatory agents, and increased nitric oxide (NO) synthesis. Our purpose was to assess supplementation of mothers with GDM with 600 mg/day DHA (randomized to receive DHA or placebo, corn oil) (week 24 of pregnancy‐delivery, GDM mothers, n=31). Blood samples were collected at weeks 24 and 36 in pregnancy. At delivery, blood from the mother and umbilical cord were collected to assess transfer of DHA from mother to fetus and placental tissue for NO synthesis. DHA supplementation significantly increased maternal red blood cell (RBC) DHA concentration but not fetal RBC DHA. Supplementation reduced fasting glucose in GDM compared to controls and insulin resistance tended to decrease substantially more in supplemented mothers than controls. Inflammatory markers were not different between the groups, likely explained on the basis of small sample size. Placental endothelial cells from controls had increased L‐arginine utilization and elevated NO synthesis compared to the DHA supplementation group. We hypothesize that DHA decreased expression of L‐arginine transport protein and/or diminished activity of endothelial NO synthase. In conclusion, DHA supplementation of women with GDM demonstrated favorable effects regarding glucose metabolism and the NO synthetic pathway compared to controls, underscoring the importance of this n‐3 long chain fatty acid in pregnancy complicated by diabetes. (Fondo Nacional de Innovacion en Salud de Chile and Nestle)