The Astrocytic Microdomain as a Generative Mechanism for Local Plasticity

Polykretis, Ioannis; Иванов, В. А.; Michmizos, Konstantinos P.

doi:10.1007/978-3-030-05587-5_15

Cited by 6 publications

(6 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We modified our 2-dimensional astrocytic model replicating the stellate structure of astrocytes and emulating the spatial allocation of the subcellular organelles in different compartments [17], [18]. Briefly, our model comprised of a somatic compartment, which extended to a number of thick branches ( Fig.…”

Section: Methodsmentioning

confidence: 99%

Computational Astrocyence: Astrocytes encode inhibitory activity into the frequency and spatial extent of their calcium elevations

Polykretis

Иванов

Michmizos

2019

2019 IEEE EMBS International Conference on Biomedical &Amp; Health Informatics (BHI)

Self Cite

View full text Add to dashboard Cite

Deciphering the complex interactions between neurotransmission and astrocytic Ca 2+ elevations is a target promising a comprehensive understanding of brain function. While the astrocytic response to excitatory synaptic activity has been extensively studied, how inhibitory activity results to intracellular Ca 2+ waves remains elusive. In this study, we developed a compartmental astrocytic model that exhibits distinct levels of responsiveness to inhibitory activity. Our model suggested that the astrocytic coverage of inhibitory terminals defines the spatial and temporal scale of their Ca 2+ elevations. Understanding the interplay between the synaptic pathways and the astrocytic responses will help us identify how astrocytes work independently and cooperatively with neurons, in health and disease.

show abstract

Section: Methodsmentioning

confidence: 99%

Computational Astrocyence: Astrocytes encode inhibitory activity into the frequency and spatial extent of their calcium elevations

Polykretis

Иванов

Michmizos

2019

2019 IEEE EMBS International Conference on Biomedical &Amp; Health Informatics (BHI)

Self Cite

View full text Add to dashboard Cite

show abstract

“…Given that oscillations and synchronization are fundamental components of information processing in the brain [16], understanding the role that neuronal and non-neuronal cells have in higher cognitive functions is crucial. This challenges the long-held notion of glial passivity in information processing and reveals potential roles for non-neuronal cells proposed by us and others [18,19]. For instance, since oligodendrocytes are now known to adaptively affect AP velocity, through actively restructuring white matter [1,17], this study paves the way for computationally studying the interaction of neuronal and nonneuronal cells in brain health and disease.…”

Section: Discussionmentioning

confidence: 79%

Axonal Conduction Velocity Impacts Neuronal Network Oscillations

Иванов

Polykretis

Michmizos

2019

2019 IEEE EMBS International Conference on Biomedical &Amp; Health Informatics (BHI)

Self Cite

View full text Add to dashboard Cite

Increasing experimental evidence suggests that axonal action potential conduction velocity is a highly adaptive parameter in the adult central nervous system. Yet, the effects of this newfound plasticity on global brain dynamics is poorly understood. In this work, we analyzed oscillations in biologically plausible neuronal networks with different conduction velocity distributions. Changes of − (ms) in network mean signal transmission time resulted in substantial network oscillation frequency changes ranging in − (Hz). Our results suggest that changes in axonal conduction velocity may significantly affect both the frequency and synchrony of brain rhythms, which have well established connections to learning, memory, and other cognitive processes.

show abstract

“…This molecular functionalization process might involve individual or small groups of synapses covered by thin (nanometer scale) or thick (∼10-15 μm 2 ) microdomains, respectively (31,47,48). It is worthy of note that the dimensions of thick microdomains coincide with the reported maximum distance between functionally related spines (49). Studies on neurons in the visual cortex have recently reported that dendritic spines, within less than ±10 m 2 distance, tend to share receptive field properties, while more distant spines are functionally uncorrelated (50).…”

Section: Discussionmentioning

confidence: 80%

Astrocytic Microdomains Confine A “molecular Memory” Enabling Long-Term Information Storage for Memory Consolidation

Vignoli

Sansevero

Sasi

et al. 2021

Preprint

View full text Add to dashboard Cite

Memory consolidation requires astrocytic microdomains for protein recycling; but whether this lays a mechanistic foundation for long-term information storage remains enigmatic. Here we demonstrate that persistent synaptic strengthening invited astrocytic microdomains to convert initially internalized (pro)-brain-derived neurotrophic factor (proBDNF) into active prodomain (BDNFpro) and mature BDNF (mBDNF) for synaptic re-use. While mBDNF activates TrkB, we uncovered a previously unsuspected function for the cleaved BDNFpro, which increases TrkB/SorCS2 receptor complex at post-synaptic sites. Astrocytic BDNFpro release reinforced TrkB phosphorylation to sustain long-term synaptic potentiation and to retain memory in the novel object recognition behavioral test. Thus, the switch from one inactive state to a multi-functional one of the proBDNF provides post-synaptic changes that survive the initial activation (molecular memory). This molecular asset confines local information storage in astrocytic microdomains to selectively support memory circuits.

show abstract

The Astrocytic Microdomain as a Generative Mechanism for Local Plasticity

Cited by 6 publications

References 48 publications

Computational Astrocyence: Astrocytes encode inhibitory activity into the frequency and spatial extent of their calcium elevations

Computational Astrocyence: Astrocytes encode inhibitory activity into the frequency and spatial extent of their calcium elevations

Axonal Conduction Velocity Impacts Neuronal Network Oscillations

Astrocytic Microdomains Confine A “molecular Memory” Enabling Long-Term Information Storage for Memory Consolidation

Contact Info

Product

Resources

About