The influence of the astrocyte field on neuronal dynamics and synchronization

Abstract

Astrocytes can sense local synaptic release of glutamate by metabotropic glutamate receptors. Receptor activation in turn can mediate transient increases of astrocytic intracellular calcium concentration through inositol 1,4,5-trisphosphate production. Notably, the perturbation of calcium concentration can propagate to other adjacent astrocytes. Astrocytic calcium signaling can therefore be linked to synaptic information transfer between neurons. On the other hand, astrocytes can also modulate neuronal activity by feeding back onto synaptic terminals in a fashion that depends on their intracellular calcium concentration. Thus, astrocytes can also be active partners in neuronal network activity. The aim of our study is to provide a computationally simple network model of mutual neuronastrocyte interactions, in order to investigate the possible roles of astrocytes in neuronal network dynamics. In particular, we focus on the information entropy of neuronal firing of the whole network, considering how it could be affected by neuron-glial interactions.

Modeling the contribution of neuron-astrocyte cross talk to slow blood oxygenation level-dependent signal oscillations

“…It should be realized that this does not imply that regular astrocytic Ca 2ϩ oscillations set uniformity on neuronal firing patterns. On the contrary, theoretical studies indicate that robust neuronal synchronization is effectively broken by neuron-astrocyte interactions, which however promote increased levels of complexity in the periodic fluctuations of neuroglial network (see Allegrini et al 2009). …”

Autaptic Modulation of Electrical Activity in a Network of Neuron-Coupled Astrocyte

“…In fact, most of the previous works about neurodynamics have discussed the neuron-coupled astrocyte model [30][31][32][33][34] and some results could be helpful to understand the occurrence of seizure-like behavior [35]. Based on the wellknown neuron models, networks with different topological connections have been set to investigate the synchronization stability [36,37], pattern selection, and mode transition in collective behaviors [38][39][40][41][42][43][44][45].…”

Alteration of Neuron-Glia Interactions in Neurodegeneration: Molecular Biomarkers and Therapeutic Strategy

“…Astroglial calcium signaling can be linked to synaptic transduction between neurons and neuronal-astroglial metabolic coupling (Allegrini et al, 2009). Cx43-formed gap junctions extensively couple neurons with glia (Nagy et al, 2004), and astrocytes represent the largest gap junction-coupled cellular network within the brain (Nakase & Naus, 2004).…”