Role of SPARC on hippocampal function

CAMPOLONGO M; BENEDETTI L; PODHAJCER O; DEPINO A

Huerta Grande

Congreso; XXVI Congreso Annual de la Sociedad Argentina de Investigación en Neurociencia; 2011

Sociedad Argentina de Neurociencias

It is estimated that about 10% of the world population suffers from depression at some point in their lives. However, genetic and environmental factors that contribute to this disorder are only beginning to be found. SPARC (secreted protein acidic and rich in cysteine) is an extracellular matrix protein highly expressed in the developing brain and in the adult hippocampus after deafferentation. However, its expression and function in the brain has only begun to be understood. We observed that SPARC KO mice present high levels of anxiety-related behaviors, while they show low levels of depression-related behaviors. By injecting an adenoviral vector that expresses SPARC in the dentate gyrus (DG) of SPARC KO mice, we rescued the depression-related, but not the anxiety-related, phenotype. We hypothesized that alterations in neuronal activity during development in SPARC KO mice results in long-term alterations in the structure and function of the DG, which determine the alterations observed in behavior. We evaluated whether neuronal activity was altered in the KO DG by studying c-fos expression. Moreover, we studied whether SPARC levels in the DG can modulate neurogenesis. Our results show a role of hippocampal SPARC in the expression of depression-related behaviors.