Table 2.

Overview of signaling pathways and their associated molecules.

Signaling pathways	Composition structure	Signal molecules	Activation paths	Clinical effects
NF-κB	NF-κB1, NF-κB2, NF-κB3, et al.	IL-6, iNOS, ICAM1, MMP-9, COX-2, et al.	Enhances M1 activation, attenuates M2 response	Inhibits inflammatory response and increases neuroprotection
JAK – STAT	JAKs and STAT1–6	INF-γ, LPS, IL-10, IL-4	Selectively activate M1 and M2	Reduce the release of inflammatory factors and accelerate the repair of damaged nerves
Notch	Four Notch receptors (Notch 1–4) and five Notch ligands (Delta type 1, 3, 4, sawtooth 1, 2)	unknow	Inhibit transition for M1–M2	Promote the release of inflammatory transmitters and aggravate nerve tissue damage
TLRs	a C-terminal TIR domain, a transmembrane region and an extracellular N-terminal	Pathogen-associated moleculars	Activation signaling pathways of NF-κB and MAPK	Increases pro-inflammatory factors and aggravates nerve damage

IL, interleukin; ICAM1, intercellular cell adhesion molecule-1; MMP-9, Matrix Metalloproteinase 9; COX-2, Cyclooxygenase-2; INF-γ, Interferon-γ; LPS, Lipopolysaccharide; MAPK, Mitogen-activated protein kinase.