Ken Kakuya, Assistant Professor of the Graduate School of Medicine, University of Hokkaido, has collaborated with Professor Mark Tuszynski's group at the University of California, San Diego, and Professor Su-Chun Zhang's group at the University of Wisconsin. He announced that he had succeeded in improving the delicate motor function of the paralyzed upper limbs by regenerating a neural circuit called the spinal tract after the spinal cord injury.The results of this research were published in Nature Medicine.
The neural circuit that controls fine movements (voluntary and delicate movements) like using fingers is called the corticospinal tract, which connects the cerebrum and spinal cord.Regeneration of the corticospinal tract is important for recovery of motor paralysis after spinal cord injury, but there has been no effective regeneration method so far.
This time, it was found that the corticospinal tract is vigorously regenerated by transplanting spinal cord-derived neural stem cells into the injured part of the spinal cord and reconstructing the nerve defect with new spinal cord tissue using rats.However, when reconstructed with nerve tissue other than the spinal cord, the corticospinal tract did not regenerate, and it was shown that the degree of regeneration was poor.In addition, regeneration of the corticospinal tract by this method improved the skillful motor function of the upper limbs of the paralyzed rat.Furthermore, it was confirmed that when similar neural stem cells were prepared from human iPS cells and transplanted into rats, they had a similar corticospinal tract regeneration effect.
The development of a regeneration method for the corticospinal tract is said to lead to research to elucidate the regeneration mechanism of the central nervous system and development research of new treatment methods.In addition, neural stem cell transplantation is expected to improve motor function in patients with SCI.
