Effect of growth restriction on early brain development: a MRI quantitative assessment

BARBEITO ANDRES J.; BERNAL V; HALLGRIMSSON B; GONZALEZ P

Congreso; Segundo Congreso de la Federacion de América Latina y el Caribe de Sociedades de Neurociencias; 2016

Intrauterine growth restriction (IUGR) is a condition where fetus reaches suboptimal values for body weight and other parameters due to a chronic reduction of oxygen and nutrients. Under these adverse conditions, brain growth is relatively preserved in comparison to other organs and tissues, although it is less clear how different brain substructures are affected. Here, we experimentally reproduced IUGR using a maternal undernutrition model in mice. Samples consisted of adult mice whose mothers were fed either control, low calorie-protein or low protein diets during pregnancy and lactation. Magnetic resonance images of brains were obtained and different cortical and subcortical regions of interest (ROIs) were segmented. Absolute and relative ROIs volumes were compared between experimental groups and their allometric patterns were analyzed to test if restricted groups follow the pattern found among small and large brains in controls. Results indicated that brain volume had a general reduction in both restriction treatments. The magnitude of reduction in volume varied across brain regions, suggesting that smaller brains in restricted groups are not an isometrically-scaled version of the control brains. Those ROIs that resulted more affected by maternal malnutrition are characterized by a slow rate of prenatal growth, while structures displaying early rapid increase of size remain mostly unaffected. Some exceptions to this pattern could be linked to adaptive mechanisms that unfold during pregnancy.