Maternal low protein diet alters the development of reward circuits from childhood to adulthood by reshaping its function

Inadequate nutrition during pregnancy can lead to intrauterine growth retardation and low birth weight, which in turn increases the risk of developing metabolic disorders in adulthood, according to various epidemiological and clinical studies. The inclination of individuals born with low birth weight towards palatable foods indicates a possible modification in the hedonic aspect of their eating behavior. However, our understanding of the ontogenesis of structural organization and function within the brain’s reward circuits remains limited. Therefore, the objective of this research is to investigate the preferences for palatable food, molecular signatures of reward circuits, and functional properties of the nucleus accumbens (NAc) in a rat model of perinatal protein restriction (LP). Starting from weaning, continuing into adolescence and adulthood, a longitudinal analysis was conducted on rats born to mothers with protein-restricted diets during gestation and lactation (LP pups), comparing them to pups born from control dams (CD pups). The LP group exhibited an increased preference for palatable food at day 25 after birth (P25), followed by a decreased preference during adolescence (P50), and no significant difference in palatable food preference at P95 (young adult) compared to CD rats. Molecular and electrophysiological assessments of medium spiny neurons (MSN) in the NAc revealed a reorganization of reward circuits during crucial developmental periods, potentially influencing the attractiveness of palatable food for the LP group. This study represents the first exploration of how preferences for palatable food evolve throughout an individual’s lifespan and how these observations correlate with the remodeling of reward circuits. By shedding light on the molecular and functional aspects of reward circuits, we contribute to a better understanding of the link between perinatal nutrition, behavioral preferences, and the underlying neural mechanisms.