Table 2.

Injury Phenotypes of Mice Deficient in MMP.

MMP Knock-Out Mice	Model	Mechanism	Phenotype	References
MMP-2 -/-	SCI	Elimination of MMP-2; compensatory increase in MMP-9	Reduced white matter sparing and fewer serotonergic fibers, widespread reactive astrogliosis, and impairment in locomotor recovery.	[17]
MMP-12 -/-	SCI	Elimination of MMP-12	Improved functional recovery, attenuation of barrier disruption, and reduces microglial/macrophages.	[19]
MMP-9 -/-	SCI	Elimination of MMP-9	Improved function recovery and reduced barrier disruption, neutrophil infiltration, neuropathic pain and inflammatory pain.	[5, 43]
Candidate Therapeutics
MMP-2/MMP-9 inhibitor, subcutaneous	SCI	Inhibit MMPs, especially MMP-9 and MMP-2	Reduced apoptosis in neurons and glia.	[32]
GM6001, intraperitoneal	Spinal nerve crush		Increased cell survival and attenuation of mechanical allodynia, degradation of myelin basic protein, macrophage influx, and glial activation.	[44]
Inhibitor I, intrathecal	Spinal nerve ligation	Inhibit MMP-9	Ameliorated early neuropathic pain behavior	[43]
Inhibitor-III, intrathecal	Spinal nerve ligation	Inhibit MMP-2	Ameliorated late neuropathic pain behavior	[43]
SB-3CT, intrathecal	SCI	Inhibit MMPs, especially MMP-9 and MMP-2	Reduced MMP activity, barrier disruption, and apoptosis.	[6]

MMP = matrix metalloproteinases; SCI = spinal cord injury.