Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.05.237420v1?rss=1 Authors: Popov, A., Brazhe, A., Denisov, P., Sutyagina, O., Lazareva, N., Verkhratsky, A., Semyanov, A. Abstract: Little is known about age-dependent changes in structure and function of astrocytes and of the impact of these into the cognitive decline in the senescent brain. The prevalent view on age-dependent increase in reactive astrogliosis and astrocytic hypertrophy requires scrutiny and detailed analysis. Using two-photon microscopy in conjunction with 3D reconstruction, Sholl and volume fraction analysis we demonstrate a significant reduction in the number and the length of astrocytic processes, in astrocytic territorial domains and in astrocyte-to-astrocyte coupling in the aged brain. Probing physiology of astrocytes with patch-clamp and Ca2+ imaging revealed deficits in K+ and glutamate clearance, and spatiotemporal reorganization of Ca2+ events in old astrocytes. These changes paralleled impaired synaptic long-term potentiation (LTP) in hippocampal CA1 in old mice. Our findings may explain astroglial mechanisms of age-dependent decline in learning and memory. Copy rights belong to original authors. Visit the link for more info