Among the most challenging areas of regeneration research is nerve regeneration/repair after injury. This is especially an issue in the central nervous system, in which axons display far less regenerative capacity than those in the peripheral nervous system. The most tragic case of this is spinal cord injury, which the medical community has never been able to effectively treat, other than to stabilize the patient. This problem has classically been considered one mainly of environment, as the central nervous system normally contains molecules that are deleterious to axonal regeneration, and even more such molecules are produced after injury. A "glial scar" forms after the spinal cord is injured wherein activated microglia induce the manufacture of chondroitin sulfate proteoglycans, which strongly deter axonal growth/regeneration. Recent studies suggest, however, that intrinsic factors in adult neurons limit the growth potential of mature axons after injury compared to the axons of developing neurons. Various strategies have been proposed to augment the capacity of injured axons to regenerate, such as treating the neurons with cocktails of growth factors and/or enzymatically digesting components of the glia scar, but such approaches have thus far not lived up to the hope that they would enable human patients to regenerate injured nerves in the central nervous system. When the regeneration field was younger, a good deal of the research centered on axonal transport and cytoskeleton, but a dead end was reached in terms of translating the conclusions of these studies into therapy. More recently, however, there has been a resurgence of attention on microtubules as an avenue to augment nerve regeneration (with quite hopeful results produced in experimental platforms), but still nothing readily translated to the clinic. Our results with nanoparticles suggest that this approach, readily translatable to the clinic, can produce profoundly positive results when our target genes are knocked down.
A primary impediment to recovery after spinal cord injury is the "glial scar," formed by reactive astrocytes that release factors which inhibit axon regrowth towards their appropriate targets. MicroCures Enhancer technology promotes axon growth through the glial scar.