Multiomic survey of secondary senescence in peripheral tissues from atherosclerotic mice

National Institute On Aging

Investigators

Abstract

The benefit of a technique such as single nuclei multiome sequencing includes the use of frozen tissue; therefore, we have been able to begin testing nuclei isolation protocols on selected tissues, such as the brain and spleen, from our mouse tissue bank. In this study, we will employ single nuclei ATAC- and RNA-seq to determine the presence of senescent cells in various tissues and determine if there are any universal or unique senescent DNA or RNA elements that can be leveraged for developing therapeutics. We will then assess the same tissues for impaired function and further determine if suppressing the SASP from senescent cells improves not only atherosclerosis but all affected tissues. Thus far, we have first screened every organ we intend to use for multiome analysis for senescence markers by RT-qPCR. The results demonstrated that senescence markers were increased in the peripheral tissues of atherosclerotic mice, including the fat, spleen, kidney and lung. We next isolated nuclei from healthy and atherosclerotic mouse brains and livers and performed single nuclei ATAC- and RNA-seq. Preliminary results suggests brain nuclei can be used for clustering cell types, revealing 12 cell populations present in the brain of mice. We plan to compare the RNA changes with the ATAC results to determine if the transcriptome agrees with or is dissimilar from the chromatin accessibility, and whether a senescence signature can be obtained from this data for each tissue.