Departments of 1Physical Medicine & Rehabilitation, 2Neurobiology, and 3Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
4School of Science, Technology and Engineering Management, St. Thomas University, Miami Gardens, FL, USA

Abstract 

Spinal cord injury (SCI) in mammals results in functional deficits that are mostly permanent due in part to the inability of severed axons to regenerate. Several types of growth-inhibitory molecules expressed at the injury site contribute to this regeneration failure. The responses of axons to these inhibitors vary greatly within and between organisms, reflecting axons’ characteristic intrinsic propensity for regeneration. In the zebrafish (Danio rerio) many but not all axons exhibit successful regeneration after SCI. This review presents and compares the intrinsic and extrinsic determinants of axonal regeneration in the injured spinal cord in mammals and zebrafish. A better understanding of the molecules and molecular pathways underlying the remarkable individualism among neurons in mature zebrafish may support the development of therapies for SCI and their translation to the clinic.

Keywords

spinal cord injury; axonal regeneration; growth inhibition; functional recovery; zebrafish

[SpringerLink]