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bioRxiv · 10.1101/2020.08.05.237420

Astrocytes dystrophy in ageing brain parallels impaired synaptic plasticity

Popov, A.·Brazhe, A.·Denisov, P.·Sutyagina, O.·Lazareva, N.·Verkhratsky, A.·Semyanov, A.
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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.

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Popov, A., Brazhe, A., Denisov, P., Sutyagina, O., Lazareva, N., Verkhratsky, A., Semyanov, A.. 2020-08-05. Astrocytes dystrophy in ageing brain parallels impaired synaptic plasticity. https://doi.org/10.1101/2020.08.05.237420

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