Developmental docosahexaenoic and arachidonic acid supplementation improves adult learning and increases resistance against excitotoxicity in the brain.

Through metabolic imprinting mechanisms a number of bioactive molecules including polyunsaturated fatty acids affect brain functions in the developmental age and longer-lasting beneficial effects are expected. In this study pregnant rats were offered diets either containing no docosahexaenoic acid (DHA) and arachidonic acid (AA) (Placebo diet) or an excess amount of these long chain polyunsaturated fatty acids (LC-PUFA) (Supplement diet) up to the time of weaning. Bilateral N-methyl-D-aspartate (NMDA) induced neurodegeneration in the entorhinal cortex of offspring in the age of 4 months was used as a tool to investigate the neuroprotective property of the developmentally supplemented DHA and AA treatments. Hippocampus-dependent spatial learning was measured in Morris water maze and the extent of neuronal lesion in the injected brain area was evaluated. Under baseline condition, in intact or sham-lesioned rats, the Morris water maze performance was superior in the supplemented group compared to the placebo controls. NMDA-lesion in the entorhinal cortex area decreased spatial learning in the supplement-treated rats while insignificantly diminished it in the placebo controls. The same supplementation attenuated the lesion size induced by the NMDA injection into the entorhinal and ventral hippocampal areas. We concluded that LC-PUFA supplementation during fetal and early postnatal development results in long-term enhancement of spatial learning ability of the offspring and offers resistance against excitotoxic brain lesion which lasts up to the adult age.

Perinatal polyunstaurated fatty acids supplementation causes alterations in fuel homeostasis in adult male rats but does not offer resistance against STZ-induced diabetes.

Maternal factors can have major imprinting effects on homeostatic mechanisms in the developing fetus and newborn. Here we studied whether supplemented perinatal polyunsaturated fatty acids (PUFAs) influence energy balance and fuel homeostasis later in life. Between day 10 after conception and day 10 after delivery, female rats were subjected to chow enriched with 10% fish-oil (FO-rich). Fish oil contains high concentrations of n-3 biosynthesis endpoint products, which may have caused the increased membrane phospholipid incorporation (particularly derived from the long-chain 20 +:n-3 PUFAs) in 10-day old pup brains. Adult male offspring of FO-rich fed rats had reduced body weight (- 20%) at 3 months, and had lower levels of plasma leptin (- 54%), insulin (- 41%), triglycerides (- 65%), and lactate (- 46%) than controls. All differences between groups were lost 48 h after streptozotocin (STZ) treatment. At 4.5 months of age, body weights of FO-rich were still lower (- 6%) than controls, but were associated with increased food intake, and increased insulin sensitivity (following intraperitoneal injection) to lower blood glucose levels relative to controls. We concluded that perinatal FO supplementation has lasting effects on body weight homeostasis and fuel metabolism in male offspring, but does not offer resistance against STZ-induced diabetes.