Cellular transport could help spinal cord nerves recover from injury

Injuries to the spinal cord often lead to paralysis, markedly affecting sufferers and their families. One of the unsolved 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 the fibers of the peripheral nervous system (which innervate the limbs and organs of the body) have this ability to regenerate. 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) of 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 from dorsal root ganglia, structures with fibers that extend to the periphery of the body and to the spinal cord. Only peripheral fibers regenerate after an injury; fibers extending into the spinal cord do not have this ability. The team found that injured cells in the periphery experience increased transport of molecules and components of the cell along the fibers toward the injury site. Surprisingly, the same happens in the central fibers, which connect to the spinal cord.

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

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