臨床神経学

<シンポジウム(1)―1―2>脳卒中:脳保護研究の現状と展望(Neuroprotection-Update)

虚血性白質障害の分子機構と新たな防御戦略

卜部 貴夫

順天堂大学医学部附属浦安病院脳神経内科〔〒279―0021 千葉県浦安市富岡2―1―1〕

Brain white matter lesions (WMLs), which are often observed in patients with ischemic cerebrovascular diseases, contribute to cognitive decline. We analyzed the pathologic and regenerative processes in brain white matter lesions of patients diagnosed with vascular dementia. There was a significant increase in the number of oligodendrocyte progenitor cells (OPCs) in the brains of patients with vascular dementia as well as in rats with cerebral hypoperfusion. WMLs can be induced experimentally by bilateral common carotid artery ligation (BCCAL) of rats to cause chronic cerebral ischemia. After chronic cerebral hypoperfusion injury, oxygen free radicals and activated microglia acting as inflammatory elements contribute to chronic cerebral hypoperfusion-induced WMLs. The cell death of oligodendrocytes (OLGs) contributes directly to WMLs. The activation for intracellular signaling pathway of cAMP responsive element binding protein (CREB) phosphorylation in the white matter was suppressed after BCCAL. Type III phosphodiesterase inhibitor (PDE3-I) has potential therapeutic and brain-protective effects based on multitarget mechanism through cell signaling pathway of CREB phosphorylation. The OPCs subsequently underwent cell death and the number of OLGs decreased. In the rat model, PDE3-I prevented cell death, markedly increased the mature OLGs, and promoted restoration of white matter and recovery of cognitive decline.
Full Text of this Article in Japanese PDF (232K)

(臨床神経, 52:908−910, 2012)
key words:虚血性白質障害,慢性脳低灌流,オリゴデンドロサイト前駆細胞,細胞内シグナル伝達系,CREBリン酸化

(受付日:2012年5月23日)