瑞典卡羅林斯卡醫(yī)學(xué)院研究人員最新發(fā)現(xiàn),人類大腦在中風(fēng)后,,其室管膜細(xì)胞也在發(fā)揮修復(fù)受損傷部位的作用,。
醫(yī)學(xué)界一直認(rèn)為,大腦在受中風(fēng)創(chuàng)傷后,,只有一種干細(xì)胞負(fù)責(zé)進(jìn)行自我修復(fù),,即通過這種干細(xì)胞分化新的神經(jīng)細(xì)胞來修復(fù)受損部位。
現(xiàn)在,,卡羅林斯卡醫(yī)學(xué)院的研究人員以老鼠為對(duì)象進(jìn)行的動(dòng)物實(shí)驗(yàn)證實(shí),,大腦中風(fēng)后室管膜細(xì)胞也在幫助受損部位產(chǎn)生新的神經(jīng)細(xì)胞,而在正常情況下,,這種細(xì)胞并不發(fā)揮這一功能,。
這一研究成果發(fā)表在最新一期英國《自然神經(jīng)學(xué)》雜志上。研究人員在報(bào)告中說,,醫(yī)學(xué)界可以根據(jù)他們的這一發(fā)現(xiàn)改進(jìn)目前的中風(fēng)治療方案,。但他們也表示,這一發(fā)現(xiàn)僅處于開始階段,,還需要進(jìn)行大量研究和探索,,才可能真正應(yīng)用于臨床治療。(生物谷Bioon.com)
生物谷推薦原始出處:
Nature Neuroscience Published online: 22 February 2009 | doi:10.1038/nn.2268
Forebrain ependymal cells are Notch-dependent and generate neuroblasts and astrocytes after stroke
Marie Carlén1,7, Konstantinos Meletis1,7, Christian G?ritz1, Vladimer Darsalia2,3, Emma Evergren4, Kenji Tanigaki5, Mario Amendola6, Fanie Barnabé-Heider1, Maggie S Y Yeung1, Luigi Naldini6, Tasuku Honjo5, Zaal Kokaia2,3, Oleg Shupliakov4, Robert M Cassidy1, Olle Lindvall2,3 & Jonas Frisén1
Abstract
Neurons are continuously generated from stem cells in discrete regions in the adult mammalian brain. We found that ependymal cells lining the lateral ventricles were quiescent and did not contribute to adult neurogenesis under normal conditions in mice but instead gave rise to neuroblasts and astrocytes in response to stroke. Ependymal cell quiescence was actively maintained by canonical Notch signaling. Inhibition of this pathway in uninjured animals allowed ependymal cells to enter the cell cycle and produce olfactory bulb neurons, whereas forced Notch signaling was sufficient to block the ependymal cell response to stroke. Ependymal cells were depleted by stroke and failed to self-renew sufficiently to maintain their own population. Thus, although ependymal cells act as primary cells in the neural lineage to produce neurons and glial cells after stroke, they do not fulfill defining criteria for stem cells under these conditions and instead serve as a reservoir that is recruited by injury.
1 Department of Cell and Molecular Biology, Medical Nobel Institute, Karolinska Institute, SE-171 77 Stockholm, Sweden.
2 Wallenberg Neuroscience Center, University Hospital, SE-221 84 Lund, Sweden.
3 Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, University Hospital, SE-221 84 Lund, Sweden.
4 Department of Neuroscience, Karolinska Institute, SE-171 77 Stockholm, Sweden.
5 Department of Medical Chemistry, Graduate School of Medicine, Kyoto University, Konoecho, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
6 Telethon Institute for Gene Therapy, San Raffaele Institute, via Olgettina 58, 20132 Milan, Italy.
7 Present address: Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.