TABLE 2.

The role of the different brain population to mechanical stimuli.

CNS cell population	Mechanical cue			References
	Topography	Stiffness	Shear forces
NSC	Topographical cues along with protein interactions determine the migration and morphology of NSCs	Stiff: OPC and astrocytic differentiation favored Soft: neuron differentiation favored	Static stretch induces differentiation toward neurons and astrocytes	Saha et al., 2008; Banerjee et al., 2009; Leipzig and Shoichet, 2009; Arulmoli et al., 2015; Czeisler et al., 2016
Neurons	Align their trajectories with topographic cues	Soft: favors neuron differentiation	–	Georges et al., 2006; Jiang et al., 2007; Rocha et al., 2014; Lantoine et al., 2016
Astrocytes	Nanofibers ameliorate astrogliosis	Stiff: best adhesion Intermediate stiffness: spread more, complex morphologies (astrogliosis like)	Static stretch induces astrocytic differentiation	Jiang et al., 2007; Moshayedi et al., 2010; Min et al., 2013; Rocha et al., 2015; Wilson et al., 2016
Oligodendrocytes	OPCs align along microstructured platforms	Differentiation occurs within a wide range of stiffnesses (0.1–70 kPa) OPC survival: 0.7–1 kPa OPC maturation and myelination: < 1 kPa	Static stretch induces OPC differentiation	Webb et al., 1995; Bauer and Ffrench-Constant, 2009; Kippert et al., 2009; Leipzig and Shoichet, 2009; Jagielska et al., 2012, 2017; Gibson et al., 2014
Microglia	Fibrous substrates: microglia with elongated processes Flat substrates: round shaped microglia	Migration toward stiff substrates	–	Bollmann et al., 2015; Pires et al., 2015

CNS, central nervous system; NSC, neural stem cell; OPC, oligodendrocyte precursor cell.