Brain endothelial cells are exquisite sensors of age-related circulatory cues [article]

Michelle B Chen, Hanadie Yousef, Andrew C Yang, Davis Lee, Benoit Lehallier, Nicholas Schaum, Stephen R Quake, Tony Wyss-Coray
2019 bioRxiv   pre-print
Brain endothelial cells (BECs) are key elements of the blood-brain barrier (BBB), protecting the brain from pathogens and restricting access to circulatory factors. Recent studies have demonstrated that the circulatory environment can modulate brain aging, yet, the underlying processes remain largely unknown. Given the BBB's intermediary position, we hypothesized that BECs sense, adapt to, and relay signals between the aging blood and brain. We sequenced single endothelial cells from the
more » ... lls from the hippocampus-a brain region key to learning, memory, and neurogenesis- of healthy young and aged mice as well as post-exposure to inflammatory and age-related circulatory factors. We discovered that aged capillary BECs, compared with arterial and venous cells, exhibit the greatest transcriptional changes, upregulating innate immunity, antigen presentation, TGF-beta signaling and oxidative stress response pathways. Remarkably, short-term infusions of aged plasma into young mice recapitulated key aspects of this aging transcriptome, while infusions of young plasma into aged mice reversed select aging signatures, essentially rejuvenating the BBB endothelium transcriptome. We identify candidate pathways mediating blood-borne brain rejuvenation by comparing age-upregulated genes with those modulated by plasma exposure. Together, these findings suggest that the transcriptional age of BECs is exquisitely sensitive to age-related circulatory cues and pinpoint the BBB itself as a promising therapeutic target to treat brain disease.
doi:10.1101/617258 fatcat:vtpc6f4zbjdrpg4dscxgx2dbaa