我国科研人员在神经干细胞研究领域取得重要进展，由复旦大学脑科学研究院杨振纲副教授领衔的课题组通过大鼠实验，发现了神经干细胞在神经再生中的独特行为方式。这一结果提示，神经干细胞移植需要进行干预，才能起到有效治疗脑部疾病的作用，从而为神经干细胞用于脑损伤修复指明了新的道路。
这一研究成果4月23日发表在国际知名学术期刊《神经科学杂志》上，并被选为亮点文章重点介绍。
科学研究已经证实，人脑内终生都有神经干细胞，在脑内能够不断产生新的神经元，但是遗憾的是，受损伤的人脑并不能因此成功自我修复。主流观点认为，这是因为脑内神经干细胞的数量太少，因此，全世界众多科研人员大多聚焦于想方设法地扩增神经干细胞的数量。
复旦大学脑科学研究院的科研人员利用脑中风的大鼠模型，发现极易受损伤的脑区是脑部纹状体，纹状体内90％以上的神经元都是投射神经元，它们“个头”中等，浑身上下长满了“刺”，而研究发现大鼠脑部自身的神经干细胞产生的新生神经元“个头”很小，身上几乎没有“刺”，不能满足修复纹状体的要求。
研究领衔者、复旦大学脑科学研究院神经干细胞和神经发育研究组组长杨振纲副教授指出：不论是胚胎时期还是成年后，脑部神经干细胞都只能产生一定种类的神经元。大脑内有近1000亿个神经元，其中分为近1万种不同类型，神经干细胞在胚胎发育时就已经分工明确，在成人脑内找不到一种能分化出所有类型神经元的“全能干细胞”。
在这一研究的基础上，未来科学家将有望利用各种遗传学干预手段，去诱导人脑部神经干细胞分化出特定功能的神经元，治疗阿尔茨海默病、帕金森病等多种神经退行性疾病。据悉，相关探索已经在复旦大学脑科学研究院神经干细胞和神经发育研究组展开，并获得了教育部和国家自然科学基金委的课题资助。（生物谷Bioon.com）
生物谷推荐原始出处：
The Journal of Neuroscience, April 22, 2009, 29(16):5075-5087; doi:10.1523/JNEUROSCI.0201-09.2009
Brain Injury Does Not Alter the Intrinsic Differentiation Potential of Adult Neuroblasts
Fang Liu,1 * Yan You,1 * Xiaosu Li,1 Tong Ma,1 Yanzhen Nie,1 Bin Wei,1 Tiejun Li,2 Huanbing Lin,3 and Zhengang Yang1
1Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, 200032 Shanghai, People's Republic of China, 2Department of Pharmacology, School of Pharmacy, Second Military Medical University, 200433 Shanghai, People's Republic of China, and 3Department of Pharmacology, School of Pharmaceutical Sciences, Southern Medical University, 510515 Guangzhou, People's Republic of China
Correspondence should be addressed to Dr. Zhengang Yang, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, 138 Yi Xue Yuan Road, 200032 Shanghai, People's Republic of China.
Neuroblasts produced by the neural stem cells of the adult subventricular zone (SVZ) migrate into damaged brain areas after stroke or other brain injuries, and previous data have suggested that they generate regionally appropriate new neurons. To classify the types of neurons produced subsequent to ischemic injury, we combined BrdU or virus labeling with multiple neuronal markers to characterize new cells at different times after the induction of stroke. We show that SVZ neuroblasts give rise almost exclusively to calretinin-expressing cells in the damaged striatum, resulting in the accumulation of these cells during long term recovery after stroke. The vast majority of SVZ neuroblasts as well as newly born young and mature neurons in the damaged striatum constitutively express the transcription factor Sp8, but do not express transcription factors characteristic of medium-sized spiny neurons, the primary striatal projection neurons lost after stroke. Our results suggest that adult neuroblasts do not alter their intrinsic differentiation potential after brain injury.
