The neurogenerating capacity of olfactory stem cells in spinal cord lesion

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K01378
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Rehabilitation science/Welfare engineering
• Research Institution: Ibaraki Prefectural University of Health Science
• Principal Investigator: SASAKI Sei-Ichi 茨城県立医療大学, 保健医療学部, 教授 (50153987)
• Co-Investigator(Kenkyū-buntansha): 冨田 和秀 茨城県立医療大学, 保健医療学部, 教授 (00389793)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 脊髄損傷 / 嗅粘膜上皮 / 呼吸運動 / 脊髄 / 機能回復

Outline of Final Research Achievements

We examined olfactory mucosa cells transplantation in spinal cord leision results in functional recoveries of respiratory movements and axon sprouting after spinal cord injury. Spinal cord had been hemisected at the cervical spinal cord three months in advance. The recovery of discharge activities after 3 months with the phrenic nerve was confirmed in inspiratory phase. Extracelluar spikes were recorded from inspiratory neuros in the brainstem. Antidromic activation was not induced by elecrical stimulation below the spinal lebel of lesion. No respiratory interneurons were recorded in the area of spinal cord lesion. Our findings indicate that olfactory mucosa cells do not survive after transplantation and suggest that olfactory mucosa cells have mechanisms that promote a supportive environment for axon regeneration after spinal cord injury.

Free Research Field

脊髄損傷後の呼吸運動回復に関わる脳幹－脊髄の神経機構の修復過程の研究

Academic Significance and Societal Importance of the Research Achievements

実験の結果は嗅粘膜上皮細胞を脊髄損傷部へ移植した脊髄では延髄呼吸ニューロンの軸索は切断面を超えないことが示された。また、半切部では呼吸リズムを持つ介在ニューロンの活動も記録できなかった。脊髄損傷からの機能回復は嗅粘膜上皮細胞自体が神経細胞に分化し機能回復の主体となることは考えにくく、脊髄損傷からの機能回復は脊髄内の既存の神経回路の可塑的な変化が必要であることが示唆された。移植医療を進める際に移植された組織自体が分化して神経回路に組み込まれるのではないことは移植による神経回路の修復を目指す脊髄損傷の治療の概念を再考する必要がある。