Title : Long-term effects of perinatal undernutrition in the brain and behavioral gustatory development of the rat
Gestational and lactating period is a time of rapid development for the mammals. The effects of restriction of nutrients in these periods produce alterations in fetal neurogenesis, morphogenesis, synaptogenesis; and during the lactating period interferes migration, synaptogenesis, networks and behavior of the progeny. These effects can be permanent at long-term in the acquisition of cognitive development that includes alterations in attention, learning, memory and inhibition control. In the other hand, these periods are essential for normal development including food behavior, because is concurrent in a period of transition between maternal milk to solid food in which different mechanisms are conjugated to obtain selfselection and self-gratification diet. In this study we evaluate the long-term impact of the undernutrition on some gustatory structures including, tongue, papillae, taste buds, morphological and neuronal activation in the nucleus of the solitary tract in the brain of developing rats. Pregnant dams were undernourished by giving 50% of a balanced diet from G6 to G12, 60% from G13-G18, and 100% from G19-G21. On postpartum day 1, prenatally underfed (UG) pups continued the undernourishment by remaining 12h with a foster dam and 12h with a nipple-ligatted mother. The results show consistent effects associated with age and diet; undernutrition in early life leads to irreversible damage, including body and brain weight and decreased offspring birth weight. In the rat model the undernutrition in gestation and lactation period affect the development in circumvallate papillae, affecting the size and morphology, the number of taste buds and the number of apoptotic cells. Undernutrition alters the pattern of neuronal induction by sweet and sour stimuli at the second postnatal week in the nucleus of the solitary tract, particularly in the caudal and medial areas that are involved in the gustatory reflex. The early restriction in nutriments alters the social transmission in food preference showing decreased social interaction and alterations in food recognition and preferences. These data suggest that perinatal undernutrition affects the basic component of the gustatory system necessary to produce the early responses, and possibly interfering with the integration of taste input to produce the food intake interfering with food learning and the hedonic aspects of the gustatory stimuli’s.
This information is useful to know the damage suffered in early life that leads to permanent impairment in the gustatory system affecting future generations. This information would be helpful to asses in health and educational programs. In the other hand, undernutrition is responsible for the highest mortality rate in children and has long-lasting effects including, insulin resistance in adulthood, hypertension, dyslipidemia and reduce de capacity for cognitive work and possibly to understand transgenerational effects.