Institute of Neurobiology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200032, China.
Institute of Neurobiology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200032, China.
Biochem Biophys Res Commun. 2014 Jul 18;450(1):378-83. doi: 10.1016/j.bbrc.2014.05.131. Epub 2014 Jun 2.
Although previous studies implied that cerebellar stem cells exist in some adult mammals, little is known about whether these stem cells can produce new neurons and astrocytes. In this study by bromodeoxyuridine (BrdU) intraperitoneal (i.p.) injection, we found that there are abundant BrdU(+) cells in adult mouse cerebellum, and their quantity and density decreases significantly over time. We also found cell proliferation rate is diversified in different cerebellar regions. Among these BrdU(+) cells, very few are mash1(+) or nestin(+) stem cells, and the vast majority of cerebellar stem cells are quiescent. Data obtained by in vivo retrovirus injection indicate that stem cells do not produce neurons and astrocytes in adult mouse cerebellum. Instead, some cells labeled by retrovirus are Iba1(+) microglia. These results indicate that very few stem cells exist in adult mouse cerebellum, and none of these stem cells contribute to neurogenesis and astrogenesis under physiological condition.
虽然先前的研究表明一些成年哺乳动物的小脑存在干细胞，但对于这些干细胞是否能产生新的神经元和星形胶质细胞知之甚少。在这项通过腹腔内注射溴脱氧尿苷（BrdU）的研究中，我们发现成年小鼠小脑中有大量 BrdU(+)细胞，并且随着时间的推移，其数量和密度显著下降。我们还发现，不同小脑区域的细胞增殖率存在差异。在这些 BrdU(+)细胞中，很少有 mash1(+)或巢蛋白(+)的干细胞，而绝大多数小脑干细胞处于静止状态。通过体内逆转录病毒注射获得的数据表明，成年小鼠小脑的干细胞不会产生神经元和星形胶质细胞。相反，一些被逆转录病毒标记的细胞是 Iba1(+)小胶质细胞。这些结果表明，成年小鼠小脑的干细胞数量很少，而且在生理条件下，这些干细胞都不会促进神经发生和星形胶质细胞发生。
