Reorganization of descending motor pathways connecting the brain and spinal cord

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H02590
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 46020:Anatomy and histopathology of nervous system-related
• Research Institution: Niigata University
• Principal Investigator: Ueno Masaki 新潟大学, 脳研究所, 教授 (40435631)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 運動下行路 / 皮質脊髄路 / 脳梗塞 / 神経回路 / 再編

Outline of Final Research Achievements

This study aimed to understand the reorganization pattern of descending motor pathways connecting the brain and spinal cord, and their connections and functions after brain injury. Spared neural circuits undergoing plastic changes contribute to functional recovery after brain injury. However, the pattern of reorganization across various lesion sites and the neural basis of functional recovery remain poorly understood. In this study, we established mouse stroke models inducing damage to distinct cortical areas and revealed that the axons of the corticospinal tract derived from different cortical areas were reorganized differently based on the location and size of the lesions. We further found that the reorganized axons connected to specific spinal neurons in the cervical cord and contributed to motor recovery. Collectively, this study elucidated the principle of reorganization in different conditions of injuries and the structure and function of the circuit that lead to motor recovery.

Free Research Field

神経解剖学・病理学

Academic Significance and Societal Importance of the Research Achievements

本研究は、脳障害の部位や大きさ別に、異なる運動下行路が再編する機序と原理を体系化し、再編する回路網の接続と機能回復への寄与の実体を、システム-神経細胞種のレベルで明らかにしたものである。この成果は、脳卒中や脊髄損傷など、さまざまな部位や程度で皮質脊髄路をはじめとする神経回路が障害される疾患において、どのような神経回路の修復や再建が機能回復へ必要であるのか、治療標的とすべき神経基盤の理解に大きく貢献すると期待される。