biostudies-literaturePopov ARussian Science Foundatione13334https://www.ebi.ac.uk/biostudies/studies/S-EPMC7963330biostudies-literatureUnknown20(3)Little is known about age-dependent changes in structure and function of astrocytes and of the impact of these on the cognitive decline in the senescent brain. The prevalent view on the 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 reorganisation of Ca²⁺ events in old astroAging cellAstrocyte dystrophy in ageing brain parallels impaired synaptic plasticity.PMC796333020‐14‐00241Verkhratsky APopov ABrazhe ADenisov PSemyanov ALi LLazareva NSutyagina OfalseAstrocyte dystrophy in ageing brain parallels impaired synaptic plasticity.Little is known about age-dependent changes in structure and function of astrocytes and of the impact of these on the cognitive decline in the senescent brain. The prevalent view on the 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 reorganisation of Ca²⁺ events in old astro2021-01-01T00:00:00Z2021 Mar2025-04-18T13:28:36.09Z2025-04-06T23:15:00.255ZS-EPMC79633303367556910.1111/acel.13334