Yang Hao, Liu Yang, Hai Yanan, Guo Ying, Yang Shi, Li Zheng, Gao Wei-Qiang, He Zuping
State Key Laboratory of Oncogenes and Related Genes, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
Department of Urology, Shanghai Human Sperm Bank, Shanghai Institute of Andrology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shangdong Road, Shanghai, 200001, China.
Mol Neurobiol. 2015 Dec;52(3):1654-1669. doi: 10.1007/s12035-014-8966-4. Epub 2014 Nov 6.
Parkinson's disease (PD) is a common neurodegenerative syndrome characterized by loss of midbrain dopaminergic (DA) neurons. Generation of functional dopaminergic (DA) neurons is of unusual significance for treating Parkinson's disease (PD). However, direct conversion of spermatogonial stem cells (SSCs) to functional DA neurons without being reprogrammed to a pluripotent status has not been achieved. Here, we report an efficient approach to obtain morphological, phenotypic, and functional DA neurons from SSCs using a specific combination of olfactory ensheathing cell-conditioned medium (OECCM) and several defined growth factors (DGF). By following the current protocol, direct conversion of SSCs (both SSC line and primary SSCs) to neural cells and DA neurons was demonstrated by expression of numerous phenotypic genes and proteins for neural cells, as well as cell morphological features. More significantly, SSCs-derived DA neurons acquired neuronal functional properties such as synapse formation, electrophysiology activity, and dopamine secretion. Furthermore, PI3K/Akt pathway and p21/Nolz1 cascades were activated whereas Smurf2 was inactivated, leading to cell cycle exit during the conversion of SSCs into DA neurons. Collectively, this study could provide sufficient neural cells from SSCs for applications in the treatment of PD and offers novel insights into mechanisms underlying neural system development from the line of germ cells.
帕金森病（PD）是一种常见的神经退行性综合征，其特征是中脑多巴胺能（DA）神经元丧失。功能性多巴胺能（DA）神经元的产生对治疗帕金森病（PD）具有非凡的意义。然而，精原干细胞（SSCs）直接转化为功能性DA神经元而不被重编程为多能状态尚未实现。在此，我们报告了一种有效的方法，使用嗅鞘细胞条件培养基（OECCM）和几种特定的生长因子（DGF）的特定组合，从SSCs获得形态、表型和功能上的DA神经元。按照当前方案，通过众多神经细胞表型基因和蛋白质的表达以及细胞形态特征，证明了SSCs（包括SSC系和原代SSCs）直接转化为神经细胞和DA神经元。更重要的是，SSCs来源的DA神经元获得了神经元功能特性，如突触形成、电生理活动和多巴胺分泌。此外，PI3K/Akt信号通路和p21/Nolz1级联被激活，而Smurf2失活，导致SSCs向DA神经元转化过程中细胞周期退出。总之，本研究可为治疗PD提供足够的来自SSCs的神经细胞，并为生殖细胞系神经系统发育的潜在机制提供新的见解。
