Department of Human Anatomy and Histoembryology, Medical School, Southeast University, Nanjing, PR China.
J Neuropathol Exp Neurol. 2011 Sep;70(9):736-47. doi: 10.1097/NEN.0b013e31822830e5.
Glial cell line-derived neurotrophic factor (GDNF) and its receptor GFRα1 have been implicated in the survival of ventral midbrain dopaminergic (DA) neurons, but the molecular mechanisms bywhich GDNF generates DA neurons in grafted midbrain-derived neural stem cells (mNSCs) are not understood. Midbrain-derived neural stem cells isolated from rat embryonic mesencephalon (embryonic day 12) were treated with GDNF or in combination with GFRα1 small interfering RNA. Reverse transcription-polymerase chain reaction, Western blot, and immunocytochemistry were used totest the expression of the orphan nuclear receptor Nurr1 and thetranscription factor Pitx3 and newborn tyrosine hydroxylase (TH)-positive cells. Treatment of mNSCs with GDNF increased mNSCs' sphere diameter, reduced expression of caspase 3, and increased expression of Bcl-2. Glial cell line-derived neurotrophic factor-treated mNSCs enhanced Nurr1 and Pitx3 expression and the fraction of TH-, TH/Pitx3-, and TH/Nurr1-positive cells in culture. Grafted GDNF-treated mNSCs significantly decreased apomorphine-induced rotation behavior in 6-hydroxydopamine-lesioned rats. Glialcell line-derived neurotrophic factor-treated mNSCs showed increased numbers of TH/Pitx3- and TH/Nurr1-postivie cells. The effect elicited by GDNF was inhibited by small interfering RNA-mediated knockdown of GFRα1. Our data demonstrate the contribution of GDNF to DA neuron development and may also elucidate pathogenetic mechanisms in Parkinson disease and contribute to the development of novel therapies for the disorder.
胶质细胞源性神经营养因子（GDNF）及其受体 GFRα1 被认为与腹侧中脑多巴胺能（DA）神经元的存活有关，但 GDNF 如何在移植的中脑源性神经干细胞（mNSC）中产生 DA 神经元的分子机制尚不清楚。从大鼠胚胎中脑（胚胎第 12 天）分离的中脑源性神经干细胞用 GDNF 或与 GFRα1 小干扰 RNA 联合处理。逆转录-聚合酶链反应、Western blot 和免疫细胞化学用于检测孤儿核受体 Nurr1 和转录因子 Pitx3 的表达以及新生酪氨酸羟化酶（TH）阳性细胞。GDNF 处理 mNSC 增加了 mNSC 的球体直径，降低了 caspase 3 的表达，增加了 Bcl-2 的表达。GDNF 处理的 mNSC 增强了 Nurr1 和 Pitx3 的表达，以及培养物中 TH、TH/Pitx3 和 TH/Nurr1 阳性细胞的比例。移植的 GDNF 处理的 mNSC 显著减少了 6-羟多巴胺损伤大鼠的阿扑吗啡诱导的旋转行为。GDNF 处理的 mNSC 显示出更多的 TH/Pitx3 和 TH/Nurr1 阳性细胞。GFRα1 介导的小干扰 RNA 敲低抑制了 GDNF 引起的作用。我们的数据表明 GDNF 对 DA 神经元发育的贡献，也可能阐明帕金森病的发病机制，并为该疾病的新型治疗方法的发展做出贡献。
