Journal ArticleDOI
Local Ca2+ detection and modulation of synaptic release by astrocytes
Maria Amalia Di Castro,Julien Chuquet,Nicolas Liaudet,Khaleel Bhaukaurally,Mirko Santello,David Bouvier,Pascale Tiret,Andrea Volterra +7 more
TLDR
Evidence is provided that astrocytes are integrated in local synaptic functioning in adult brain through GTP- and inositol-1,4,5-trisphosphate–dependent signaling and is relevant for basal synaptic function.Abstract:
Astrocytes communicate with synapses by means of intracellular calcium ([Ca(2+)](i)) elevations, but local calcium dynamics in astrocytic processes have never been thoroughly investigated. By taking advantage of high-resolution two-photon microscopy, we identify the characteristics of local astrocyte calcium activity in the adult mouse hippocampus. Astrocytic processes showed intense activity, triggered by physiological transmission at neighboring synapses. They encoded synchronous synaptic events generated by sparse action potentials into robust regional (∼12 μm) [Ca(2+)](i) elevations. Unexpectedly, they also sensed spontaneous synaptic events, producing highly confined (∼4 μm), fast (millisecond-scale) miniature Ca(2+) responses. This Ca(2+) activity in astrocytic processes is generated through GTP- and inositol-1,4,5-trisphosphate-dependent signaling and is relevant for basal synaptic function. Thus, buffering astrocyte [Ca(2+)](i) or blocking a receptor mediating local astrocyte Ca(2+) signals decreased synaptic transmission reliability in minimal stimulation experiments. These data provide direct evidence that astrocytes are integrated in local synaptic functioning in adult brain.read more
Citations
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Age-related changes in brain support cells: Implications for stroke severity
TL;DR: The hypothesis that stroke severity in the aging brain may be associated with reduced functional capacity of critical support cells is discussed, which focuses on astrocytes, that are critical for detoxification of the brain microenvironment and endothelial cells, which play a crucial role in maintaining the blood brain barrier.
Journal ArticleDOI
Astrocyte, a Promising Target for Mood Disorder Interventions.
TL;DR: It is argued that astrocyte dysfunction affects the monoaminergic system, excitatory–inhibitory balance and neurotrophic states of local networks, and the focus from neurons to glial cells and the interactions between the two is changed to understand newly proposed mechanisms underlying mood disorders.
Journal ArticleDOI
GABAergic-astrocyte signaling: A refinement of inhibitory brain networks.
Sara Mederos,Gertrudis Perea +1 more
TL;DR: Current data supporting the existence of dynamic GABAergic‐astrocyte communication and its impact on the inhibitory‐regulated brain responses are highlighted, bringing new perspectives on the ways astrocytes might contribute to efficient neuronal coding.
Journal ArticleDOI
Connexin and pannexin signaling pathways, an architectural blueprint for CNS physiology and pathology?
Elke Decrock,Marijke De Bock,Nan Wang,Geert Bultynck,Christian Giaume,Christian C. Naus,Colin R. Green,Luc Leybaert +7 more
TL;DR: Current knowledge on Cxs and Panxs' multifaceted contribution to brain development and to specific processes in the NGVU are discussed, including synaptic transmission and plasticity, glial signaling, vasomotor control, and blood–brain barrier integrity in the mature CNS.
Journal ArticleDOI
The role of astrocytes in CNS tumors: pre-clinical models and novel imaging approaches.
TL;DR: The role of astrogliosis in both primary and secondary brain tumors is reviewed and the potential for the use of novel imaging modalities in research and clinical settings is outlined, with the potential to enhance the understanding of the local host response to tumor progression in the brain.
References
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Journal ArticleDOI
Tripartite synapses: astrocytes process and control synaptic information
TL;DR: There is an emerging view, which is reviewed herein, in which brain function actually arises from the coordinated activity of a network comprising both neurons and glia, rather than the classically accepted paradigm that brain function results exclusively from neuronal activity.
Journal ArticleDOI
Control of synapse number by glia.
TL;DR: It is shown that few synapses form in the absence of glial cells and that the fewsynapses that do form are functionally immature, and that CNS synapse number can be profoundly regulated by nonneuronal signals.
Journal ArticleDOI
Long-term potentiation depends on release of d -serine from astrocytes
Christian Henneberger,Thomas Papouin,Thomas Papouin,Stéphane H. R. Oliet,Stéphane H. R. Oliet,Dmitri A. Rusakov +5 more
TL;DR: It is demonstrated that Ca2+-dependent release of d-serine from an astrocyte controls NMDAR-dependent plasticity in many thousands of excitatory synapses nearby.
Journal ArticleDOI
Definition of the Readily Releasable Pool of Vesicles at Hippocampal Synapses
TL;DR: It is found that hypertonic solutions do not act through changes in intracellular calcium, which means that the synaptic release probability depends on the size of the readily releasable pool.
Journal ArticleDOI
Neuronal Synchrony Mediated by Astrocytic Glutamate through Activation of Extrasynaptic NMDA Receptors
TL;DR: The results reveal a distinct mechanism for neuronal excitation and synchrony and highlight a functional link between astrocytic glutamate and extrasynaptic NMDA receptors.