Expression of Ambra1 in mouse brain during physiological and Alzheimer type aging.

Autophagy is a major protein degradation pathway, essential for stress-induced and constitutive protein turnover. In the nervous tissue, autophagy is constitutively active and crucial to neuronal survival. The efficiency of the autophagic pathway reportedly undergoes age-related decline, and autophagy defects are observed in neurodegenerative diseases. Since Ambra1 plays a fundamental role in regulating the autophagic process in the developing nervous tissue, we investigated the expression of this protein in mature mouse brain and during physiological and Alzheimer type aging. The present study, while accomplishing the first complete map of Ambra1 protein distribution in the various brain areas, highlights differential expression in neuronal/glial cell populations. Differences in Ambra1 content are possibly related to specific neuronal features and properties, particularly concerning susceptibility to neurodegeneration. Furthermore, the analysis of Ambra1 expression in physiological and pathological brain aging supports important, though conflicting, functions of autophagy in neurodegenerative processes. Thus, novel therapeutic approaches, based on autophagy modulation, should also take into account the age-dependent roles of this mechanism in establishing, promoting or counteracting neurodegeneration.