Laboratory of Molecular Neurosurgery, Department of Stereotactic and Functional Neurosurgery, Neurocenter, Albert-Ludwigs-University, Breisacher Str. 64, D-79106 Freiburg, Germany.
Exp Cell Res. 2010 Mar 10;316(5):737-46. doi: 10.1016/j.yexcr.2010.01.001. Epub 2010 Jan 11.
Parkinson's disease (PD) is a neurodegenerative disorder with motor symptoms caused by the loss of dopaminergic (DA) cells and consequently dopamine release in the nigrostriatal system. In vivo and in vitro 6-hydroxydopamine (6-OHDA) PD models are widely used to study the effect of striatal dopamine depletion as well as novel neuroprotective or restorative therapeutic strategies for PD. In the present study, we investigated in vitro the toxicity of 6-OHDA on DA neurons derived from E14 rat ventral mesencephalon (VM) and the neuroprotective efficiency of erythropoietin (Epo) on VM-derived cell cultures against 6-OHDA toxicity. Using E14 VM-derived DA-rich primary cultures, we could demonstrate that 6-OHDA toxicity works in a time-and concentration-dependent way, and leads to cell death not only in DA cells but also in non-DA cells in direct relation to concentration and incubation times. In addition, we found that 6-OHDA toxicity induces caspase-3 activation and an increment of intracellular reactive oxygen species (ROS) in VM-derived cultures. When 6-OHDA-treated VMs were cultured in the presence of the anti-apoptotic protein erythropoietin (Epo), the total neuronal population, including the DA neurons, was protected. However, untreated VM cultures exposed to Epo showed an increase in the total neuronal population, but not an additional increase in DA neuron cell number. These findings suggest that 6-OHDA toxicity is time and concentration-dependent and does not exclusively affect DA neurons. In high concentration and long incubation times, 6-OHDA influences the survival of other neuronal and non-neuronal cell populations derived from the VM cultures. 6-OHDA toxicity induces caspase-3 activation, indicating cell death via the apoptotic pathway which could be restricted or even prevented by pre-exposure to Epo, known to interact via the apoptotic pathway. Our results support and expand on previous findings showing that Epo is an interesting candidate molecule to mediate neuroprotective effects on DA neurons in PD. Furthermore, it could be used in promoting the survival of DA neurons after transplantation in clinical trials.
帕金森病(PD)是一种神经退行性疾病,其运动症状是由黑质纹状体系统中多巴胺能(DA)细胞的丧失和多巴胺释放引起的。体内和体外 6-羟多巴胺(6-OHDA)PD 模型被广泛用于研究纹状体多巴胺耗竭以及 PD 的新型神经保护或恢复治疗策略的效果。在本研究中,我们研究了 6-OHDA 对源自 E14 大鼠中脑腹侧(VM)的 DA 神经元的体外毒性,以及促红细胞生成素(Epo)对 VM 衍生细胞培养物对抗 6-OHDA 毒性的神经保护效率。使用源自 E14 VM 的富含 DA 的原代培养物,我们可以证明 6-OHDA 毒性以时间和浓度依赖性的方式起作用,并且不仅导致 DA 细胞死亡,而且还与浓度和孵育时间直接相关,导致非 DA 细胞死亡。此外,我们发现 6-OHDA 毒性诱导 caspase-3 激活和 VM 衍生培养物中细胞内活性氧(ROS)的增加。当用抗凋亡蛋白促红细胞生成素(Epo)处理 6-OHDA 处理的 VM 时,包括 DA 神经元在内的总神经元群体得到保护。然而,未经处理的 VM 培养物暴露于 Epo 时,总神经元群体增加,但 DA 神经元数量没有增加。这些发现表明 6-OHDA 毒性是时间和浓度依赖性的,并且不会专门影响 DA 神经元。在高浓度和长时间孵育的情况下,6-OHDA 会影响源自 VM 培养物的其他神经元和非神经元细胞群体的存活。6-OHDA 毒性诱导 caspase-3 激活,表明通过细胞凋亡途径导致细胞死亡,而通过已知通过细胞凋亡途径相互作用的 Epo 预先暴露可以限制甚至预防这种死亡。我们的结果支持并扩展了先前的发现,表明 Epo 是一种有趣的候选分子,可以介导 PD 中 DA 神经元的神经保护作用。此外,它可用于促进临床试验中 DA 神经元移植后的存活。