Astrocytes reassessment - an evolving concept part one: embryology, biology, morphology and reactivity

Table 5 Reactive astrogliosis

Reactive astrogliois	Changes in astrocytes morphology	Changes in molecules expression
Reactive astrogliois	Changes in astrocytes morphology	Upregulated molecules	Upregulated or downregulated molecules
Mild to moderate astrogliosis	• Hypertrophy of cell body	• Structural elements: GFAP, nestin, vimentin	• Inflammatory cell regulators: cytokines, growth factors, glutathione
	• Astrocytes processes are are numerous and thicker	• Transcriptional regulators: STAT3, NFκB, Rheb-m TOR, cAMP, Olig2, SOX9 [61–65].	• Transporters and pumps: AQP4 and Na⁺/K⁺ transporters [61, 66–69]
	• Astrocytes processes are are numerous and thicker		• Glutamate transporter [70–73]
	• The non-overlapping domains of individual astrocytes are preserved		• Vascular regulators: PGE, NO [74, 75]
			• Energy provision: lactate [76]
			• Molecules implicated in synapse formation and
Severe astrogliosis and glial scar	• Intense hypertrophy of cell body		• Remodeling: thrombospondin and Complement C1q [77, 78]
	• Significant extension of processes		• Molecules implicated in oxidative stress and providing protection from oxidative stress: NO, NOS, SOD, Glutathione [67, 68, 79]
	• Proliferation
	• Overlapping of individual domains
	• Substantial reorganization of tissue architecture [60]