Astrocyte switch to the hyperactive mode

Glia, Journal Year: 2024, Volume and Issue: 72(8), P. 1418 - 1434

Published: April 9, 2024

Abstract Increasing pieces of evidence have suggested that astrocyte function has a strong influence on neuronal activity and plasticity, both in physiological pathophysiological situations. In epilepsy, astrocytes been shown to respond epileptic seizures; however, whether they can act as trigger for seizures not determined. Here, using the copper implantation method, spontaneous hyperactivity episodes were reliably induced during week following implantation. With near 24‐h continuous recording over 1 local field potential with vivo electrophysiology cytosolic Ca 2+ fiber photometry occurrences seizure captured. Approximately day after implantation, isolated aberrant events often observed before accompanied by hyperactivity, suggesting role epileptogenesis. Within single developed episode, increase preceded ~20 s, actions originating from could be occurrence seizures. Astrocyte‐specific stimulation channelrhodopsin‐2 or deep‐brain direct current was capable inducing hyperactivity. Injection an astrocyte‐specific metabolic inhibitor, fluorocitrate, able significantly reduce magnitude spontaneously occurring These results suggest triggering individual reciprocal astrocyte‐neuron interactions likely amplify exacerbate Therefore, future epilepsy treatment targeted at achieve control.

Language: Английский

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Dynamics of Neuronal and Astrocytic Energy Molecules in Epilepsy

Journal of Neurochemistry, Journal Year: 2025, Volume and Issue: 169(3)

Published: March 1, 2025

ABSTRACT The dynamics of energy molecules in the mouse brain during metabolic challenges induced by epileptic seizures were examined. A transgenic line expressing a fluorescence resonance transfer (FRET)‐based adenosine triphosphate (ATP) sensor, selectively expressed cytosol neurons, was used. An optical fiber inserted into hippocampus, and changes cytosolic ATP concentration estimated using photometry method. To induce neuronal hyperactivity, train electrical stimuli delivered to bipolar electrode placed alongside fiber. Although maintaining steady is crucial for cell survival, single episode hyperactivity drastically reduced levels. Interestingly, magnitude reduction did not increase with exacerbation epilepsy, but rather decreased. This suggests that primary consumption may be solely directed toward restoring Na + K ionic imbalance caused action potential bursts. Cytosolic reflects balance between supply consumption. investigate flux leading production, new FRET‐based pyruvate sensor developed astrocytes mice. Upon an astrocytic observed. Changes molecules, such as glucose oxygen, due blood vessel constriction or dilation, well alterations astrocyte function, contribute neurons. image

Language: Английский

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Repeated treatment with JWH-018 progressively increases motor activity and aggressiveness in male mice: involvement of CB1 cannabinoid and D1/D2 dopaminergic receptors

European Journal of Pharmacology, Journal Year: 2025, Volume and Issue: unknown, P. 177633 - 177633

Published: April 1, 2025

Language: Английский

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Astrocytes in Pain Perception: A Systems Neuroscience Approach

Advances in neurobiology, Journal Year: 2024, Volume and Issue: unknown, P. 193 - 212

Published: Jan. 1, 2024

Language: Английский

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Astrocytic determinant of the fate of long‐term memory

Glia, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 4, 2024

Abstract While some vivid memories are unyielding and unforgettable, others fade with time. Astrocytes recognized for their role in modulating the brain's environment have recently been considered integral to information processing memory formation. This suggests potential roles emotional perception In this study, we delve into impact of amygdala astrocytes on fear behaviors memory, employing astrocyte‐specific optogenetic manipulations mice. Our findings reveal that astrocytic photoactivation channelrhodopsin‐2 (ChR2) provokes aversive behavioral responses, while archaerhodopsin‐T (ArchT) diminishes perception. ChR2 amplifies encoding but obstructs its consolidation. On other hand, ArchT inhibits formation during intense stimuli, possibly due weakened However, it prevents decay remote over three weeks. Crucially, these effects were observed when coincided experience, indicating a deterministic states at exact moment experiences shaping long‐term memory. research underscores significant multifaceted perception, formation, modulation, suggesting sophisticated astrocyte‐neuron communication mechanism underlying basic state transitions brain.

Language: Английский

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