Research for blast induced traumatic brain injury

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K17050
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Emergency medicine
• Research Institution: Osaka University
• Principal Investigator: Matsuura Hiroshi 大阪大学, 医学部附属病院, 医員 (10791709)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 爆発 / 慢性外傷性脳症 / mild TBI / 衝撃波

Outline of Final Research Achievements

This study aimed to establish a rat model of behavioral abnormality caused by blast-induced mTBI and detect new findings.We used a bench-top blast wave generator. The blast wave was directed at the head of male Wistar rats. Peak shock wave pressure was 646.2 ± 70.3 kPa.After blast injury, mTBI rats did not show the findings of brain hemorrhage macroscopically and on hematoxylin-eosin-stained frozen sections. Behavioral experiments revealed short-term memory impairment at 2 weeks and depression-like behavior at 2 and 6 weeks. Diffusion-weighted ex vivo MRI showed high-intensity areas in layers of the bilateral hippocampus. Immunohistochemical analysis revealed accumulation of reactive microglia and GFAP-positive astrocytes in the same region and loss of NeuN-positive neurons in the hippocampal pyramidal cell layer.This model can reflect the pathophysiology of blast-induced mTBI and could potentially be used to develop therapeutic interventions in the future.

Free Research Field

救急医学

Academic Significance and Societal Importance of the Research Achievements

本研究は頭部局所の軽症爆傷モデルであり、ヒトで問題となっている急性期以降の症状を表現しているモデルを作成できた。そのモデルにおいて超高磁場MRIや免疫組織学的変化を捉えることができ、慢性的な炎症性変化が病態を形成していることが示唆され、今後のさらなる病態の解明や治療介入を試みるよいモデルになりうる。また、軽症頭部爆傷で生じる症状は、負傷者がさらに多い脳震盪など軽症頭部外傷でも見られ、類似点が多いため、本研究の成果は応用できる可能性がある。