Topology Drives Calcium Wave Propagation in 3D Astrocyte Networks

Glial cells are non-neuronal cells that constitute the majority of cells in the human brain and significantly modulate information processing via permanent cross-talk with the neurons. Astrocytes are also themselves inter-connected as networks and communicate via chemical wave propagation. How astrocyte wave propagation depends on the local prop- erties of the astrocyte networks is however unknown. In the present work, we investigate the influence of the character- istics of the network topology on wave propagation. Using a model of realistic astrocyte networks (> 1000 cells em- bedded in a 3d space), we show that the major classes of propagations reported experimentally can be emulated by a mere variation of the topology. Our study indicates that calcium wave propagation is favored when astrocyte connec- tions are limited by the distance between the cells, which means that propagation is better when the mean-shortest path of the network is larger. This unusual property sheds new light on consistent reports that astrocytes in vivo tend to restrict their connections to their nearest neighbors