Transcriptional and epigenetic landscape of the mouse intestine during aging identifies key molecular drivers of aging -associated dysfunctions and diseases [scRNA-seq].

Aging is a complex multifactorial process leading to the loss of tissue/organ functionality and to an increase in disease risk. Aging-related intestinal dysfunctions include loss of barrier integrity, altered stress responses, nutrient malabsorption, and cancer formation. Many molecular mechanisms related to dysfunction and diseases are well-known (e.g. in cancer), however how aging impact on them before the occurrence of dysfunctions and diseases is poorly understood. In this study, we applied a multi-layered omics-approach to characterize the transcriptional and the epigenetic landscape of mouse intestinal epithelium during aging. We found gender and cell-type specific transcriptional and epigenetic alterations on key pathways and genes linked to intestinal dysfunctions, stem cell aging, organismal lifespan and cancer. Moreover, we identified a switch in the composition of the old intestinal stem cell subpopulations, represented by a drift towards a more secretory lineage committed (and less stem) state accompanied by functional epigenetic alterations. Overall design: Transcriptional and epigenetic landscape of the mouse intestine during aging.