Saturated and unsaturated fat diets impair hippocampal glutamatergic transmission in adolescent mice

Consumption of high-fat diets (HFD) has been associated with neuronal plasticity deficits and cognitive disorders linked to the alteration of glutamatergic disorders in the hippocampus. As young individuals are especially vulnerable to the effects of nutrients and xenobiotics on cognition, we studied the effect of chronic consumption of saturated (SOLF) and unsaturated oil-enriched foods (UOLF) on: i) spatial memory; ii) hippocampal synaptic transmission and plasticity; and iii) gene expression of glutamatergic receptors and hormone receptors in the hippocampus of adolescent and adult mice. Our results show that both SOLF and UOLF impair spatial short-term memory. Accordingly, hippocampal synaptic plasticity mechanisms underlying memory, and gene expression of NMDA receptor subunits are modulated by both diets. On the other hand, PPARγ gene expression is specifically down-regulated in adolescent SOLF individuals and up-regulated in adult UOLF mice. [Display omitted] •Spontaneous alternation is modulated by diets enriched either in saturated (SOLF) or in unsaturated fatty acids (UOLF).•SOLF and UOLF impair hippocampal glutamatergic transmission in a different manner.•SOLF and UOLF modulate the expression of the hippocampal glutamate receptors Grin2A and Grin2B, as well as of PPARϒ.