SAN2020

Early obesity has been related to changes in the normal structure and function of the brain. Environmental stimulus can intensify or attenuate these changes. We analyzed the effects of an early obesity model, and the later exposure to an enriched environment (EE), over metabolic parameters, mRNA expression of key brain genes, and cognitive performance. For that, litters of Wistar rats were kept unchanged (Normal Litter, NL) or reduced to 3/4 male pups (Small Litter; SL). At postnatal day 21 (PND21), a group of NL and SL rats were sacrificed to evaluate short-term changes. The remaining animals were divided into EE and standard environment (SE) conditions, and at PND90 they were tested in the Episodic-like memory (ELM) and Locomotion activity (LA) tests, and then sacrificed to evaluate medium-term changes. CA1, CA3, and GD areas were isolated from the rat brain by micropunch technique, and gene expression of BDNF and VEGF was evaluated by Rt-qPCR. In PND21, SL showed an increase in adiposity and levels of glucose, cholesterol, and triglycerides (p <0.05). In PND90, the SL-SE group showed lower performance in the ELM test compared to SL-EE, NL-SE, and NL-EE (p<0.05). In the LA test, NL-EE showed a higher frequency of rearing compared to NL-SE, SL-SE, and SL-EE (p<0.05). Gene expression is still under study. These results show that early obesity could affect metabolic parameters and cognition in the short and medium-term, while EE could attenuate these changes.