Impact of an Extra Virgin Olive Oil-enriched Diet in Diabetic Dams on the Decidua of offspring Prone to Gestational Diabetes

Background During early pregnancy, the decidua supports embryo development and maternal adaptations to pregnancy. Maternal diabetes programs gestational diabetes mellitus (GDM) in offspring, and a pro-oxidant intrauterine environment has been implicated. Diets enriched with extra virgin olive oil (EVOO) can provide antioxidant effects. This study hypothesized that EVOO-enriched diets administered to pregestational diabetic pregnant rats (F0) would confer beneficial effects on the decidua of their early-pregnant offspring (F1), who are prone to developing GDM. Aims To evaluate signaling pathways and pro-oxidant state markers in the decidua of 9 d pregnant offspring of diabetic dams who either received or did not receive a 6% EVOO-enriched diet during the F0 pregnancy. Methods Rats with mild diabetes and controls were fed diets with or without 6% EVOO during F0 pregnancy, and their 9 d pregnant offspring were then evaluated. Markers of decidual function (prolactin, PPAR and mTOR pathways) and the pro-oxidant state were evaluated in the decidua. Results Despite normal maternal glycemia and progesterone levels, the decidua of 9 d pregnant offspring of diabetic dams exhibited reduced prolactin and mTOR pathway activity. PPAR levels decreased, while microRNAs that regulate their expression increased. These alterations were not prevented by the EVOO-enriched diet provided in the F0 generation. Levels of FABP4 (involved in decidualization and a marker of a pro-oxidant state) and lipoperoxidation were increased in the decidua of 9 d pregnant offspring of diabetic dams. The EVOO-enriched diet prevented these alterations. Conclusion Maternal diabetes programs impaired markers of decidualization and the pro-oxidant state in early-pregnancy offspring. These alterations were partially ameliorated by maternal diets enriched with EVOO.