Influence of Maternal Nutrient Restriction during the Period of Embryonic and Maximal Placental Growth on Organ Development in the Adult Sheep

Abstract

Objective: It is apparent that maternal under nutrition at specific period during pregnancy has differential effects on placental and fetal development, such that the resulting offspring is programmed to be at risk of disease in later life. The study investigated the influence of restricted maternal nutrition during the period of embryonic and maximal placental growth (i.e. 0 – 95 days gestation; term ≈147 days) on the developmental and programming of mitochondrial voltage dependent anion channel (VDAC) and cytochrome c in the lung of the resulting ovine adult. Materials and Methods: Singleton bearing ewes were nutrient restricted between 0 and 95 days of pregnancy and lung weight, the abundance of VDAC and cytochrome c were determined in the resulting adult at 3 years of age, using immunoblotting. Nutrient restricted ewes were fed 50% of their metabolisable energy (ME) requirements (4.0 MJ/day), and diet consisted of 250g hay/day and 210g/day of dried grass pellets (2.2 MJ/day). All diets contained adequate amount of vitamins and minerals. Results: Maternal nutrient restriction had no effect on lung weight, protein and total mitochondrial protein; but caused a significant reduction (P<0.05) in VDAC and cytochrome c abundance. Kidney weight was not affected but cytochrome c abundance was significantly (P<0.05) down regulated. Liver weight was significantly (P<0.05) reduced by nutrient restriction, but no effect on VDAC and cytochrome c abundance. Conclusion: Although maternal nutrient restriction over the period of embryonic and maximal placental growth has no effect on lung weight, it reduces the production of mitochondrial VDAC and cytochrome c at 3 years of age and this may affect the adaptation of the adult sheep.

Key words: Maternal, nutrient restriction, pregnancy, placenta, organ, development, Sheep