Cell transport may help spinal cord nerves recover from injuries

Spinal cord injuries often lead to paralysis, significantly affecting those who suffer from them and their families. One of the unresolved questions in neuroscience is why nerve fibers in the central nervous system (the brain and spinal cord) do not regenerate after injury. The mystery is made even more intriguing by the fact that fibers in the peripheral nervous system (which innervate the limbs and organs of the body) do have this capacity for regeneration. Thousands of scientists around the world are trying to solve this question. A team of researchers from the Institute of Molecular and Cellular Biology (IBMC) at the University of Porto now reveals that the transport of molecules and cellular components in the fibers is a potential target for the regeneration of the central nervous system.

In a study published in the Journal of Neuroscience, the team led by Mónica Sousa studied the behavior of cells in the dorsal root ganglia, structures with fibers that extend to the periphery of the body and to the spinal cord. Only peripheral fibers regenerate after injury; fibers that extend to the spinal cord do not have this ability. The team found that injured cells in the periphery show an increase in the transport of molecules and cell components along the fibers toward the site of injury. Surprisingly, the same happens in the central fibers, which connect to the spinal cord.

This phenomenon may explain why the central fibers of the dorsal root ganglia acquire the ability to regenerate: all the machinery and components necessary for injury regeneration are present and functioning. Manipulating transport in the fibers may pave the way for ways to increase the regenerative capacity of central nervous system fibers.

This study was funded by FCT through a Collaborative Research Grant project from the Harvard Medical School–Portugal Program.