SRA

Aging and increased amyloid burden are major risk factors for cognitive diseases such as Alzheimer''s Disease (AD). An effective therapy does not yet exist. Here we use mouse models for age-associated memory impairment and amyloid deposition to study transcriptome and cell type-specific epigenome plasticity at the systems level in the brain and in peripheral organs. We show that at the level of epigenetic gene-expression aging and amyloid pathology are associated with inflammation and impaired synaptic function in the hippocampal CA1 region. While inflammation is associated with increased gene-expression that is linked to a subset of transcription factors, de-regulation of plasticity genes is mediated via different mechanisms in the amyloid and the aging model. Amyloid pathology impairs histone-acetylation and decreases expression of plasticity genes while aging affects differential splicing that is linked to altered H4K12 acetylation at the intron-exon junction in neurons but not in non-neuronal cells. We furthermore show that oral administration of the clinically approved histone deacetylase inhibitor Vorinostat not only restores spatial memory, but also exhibits an anti-inflammatory action and reinstates epigenetic balance and transcriptional homeostasis at the level of gene expression and exon usage. This is the first systems-level investigation of transcriptome plasticity in the hippocampal CA1 region in aging and AD models and of the effects of an orally dosed histone deacetylase inhibitor. Our data has important implications for the development of minimally invasive and cost-effective therapeutic strategies against age-associated cognitive decline. In fact, our data strongly suggest to test Vorinostat in patients suffering from AD. Overall design: Examination of H4K12 acetylation in neuronal and non-neuronal nuclei of young/old animals and WT/APP/PS1-21 animals. Inputs are also provided.