Non pharmacological strategies to promote spinal cord regeneration: A view on some individual or combined approaches

Spinal cord injury (SCI) is a complex condition that can result in functional impairment and paralysis, and occurs more frequently in young men. Several studies tested diverse treatments; however none achieved effective neuronal regeneration or improvement in neural function. Current research is being performed in areas such as cellular therapy (Schwann cells, embryonic stem cells, pluripotent stem cells, mesenchymal stem cells and olfactory cells), growth factors (BDNF), inhibitory molecules, fibroglial scar, gene therapies, etc. Some strategies have provided encouraging results by themselves, others have been tested as a combination, showing an improved out-come after SCI. Combined strategies could be more effective than individual therapies; for instance, co transplantation of cells at the injury site to maximize their effect has been used, and it has demonstrated a greater efficacy in comparison to grafts of stem cells or of a particular cell type. The combination of neurotrophic factors such as BDNF and NT-3 enhances axonal regeneration and myelination; other therapies include the use of biological matrices in combination with inhibitors of glial scar formation. Chondroitinase ABC (ChABC) has shown synergistic effects with other strategies, specifically to improve regeneration and functional recovery after SCI. Experimental evidence suggests that it is possible to obtain better results with a combination of strategies, which justifies further research for therapeutic approaches. This review intends to compile the most relevant information about available up-to-date therapeutic strategies that are administered alone or in combination with others, and have offered the best results in neural regeneration after spinal cord injury.