Perinatal protein malnutrition-induced anhedonia is associated to a reduced hippocampal dendritic spine density and BDNF levels in the adult offspring

Villa Carlos Paz, Córdoba

Congreso; XXXIV Reunión Anual SAN; 2019

SAN

Previously we demonstrated that early protein undernutrition facilitates depressive-like behaviours in adult rats. A core symptom of depressive disorder is anhedonia or inability of experiencing pleasure. In order to elucidate possible molecular and morphological alterations associated to this symptom, adult animals submitted to a perinatal protein deprivation schedule (D-rats) and well-nourished animals (C-rats) were subjected to the sucrose preference test. Bearing in mind that it has been suggested that alterations on BDNF could contribute to the onset of depressive-like behaviour, we evaluated the levels of BDNF in different structures. After the behavioural test, animals from the different experimental groups were sacrificed and the nucleus accumbens and hippocampus dissected to determine by ELISA the levels of BDNF. Moreover, a lot of evidence associated depressive disorder with alterations in the morphology and density of dendritic spines. To evaluate whether an early nutritional insult induces changes in dendritic spiny number of CA1 hippocampal neurons, the different groups of rats were perfused for dendritic spine analysis immediately after the sucrose preference test. According to previous results, D-rats showed significantly decreased sucrose preference compared to C-rats. We also observed in D-animals increased levels of BDNF in NAc and decreased levels in hippocampus. What is more, D-animals exhibited a lower density of total dendritic spines in hippocampal neurons, particularly mature ones, than C-rats. These findings suggest that early protein undernutrition-induced anhedonia could be associated to regional differences in BDNF levels and that the down regulation of this factor could mediate the decreased dendritic spine density in hippocampal neurons. It has been suggested that alterations on BDNF in different structures could contribute to the onset of depressive-like behaviour. Moreover, a lot of evidence associated depressive disorder with alterations in the morphology and density of dendritic spines. Previously we demonstrated that early protein undernutrition facilitates depressive-like behaviours in adult rats. A core symptom of depression is anhedonia, a totally or partially lost on the capacity of experiencing pleasure. In order to elucidate possible molecular and morphological alterations associated to this symptom, adult animals submitted to a perinatal protein deprivation schedule (D-rats) and well-nourished animals (C-rats) were subjected to the sucrose preference test. After this behavioural test animals from the different experimental groups were sacrificed and the NAc and hippocampus dissected to determine by ELISA the levels of BDNF in these structures. Another group of rats, immediately after sucrose preference test, were perfused for dendritic spine analysis to evaluate whether an early nutritional insult induces changes in dendritic spiny number of CA1 hippocampal neurons. According to previous results, D-rats showed significantly decreased sucrose preference compared to C-rats. We also observed in D-animals increased levels of BDNF in NAc and decreased levels in hippocampus. What is more, D-animals exhibited a lower density of total dendritic spines in hippocampal neurons, particularly mature ones, than C-rats. These findings suggest that early protein undernutrition-induced anhedonia could be associated to regional differences in BDNF levels and that the down regulation of this factor could mediate the decreased dendritic spine density in hippocampal neurons.