An Approach to Dopamine Graft Augmentation

纹状体多巴胺（DA）的替代仍然是帕金森病（PD）治疗的主要目标。 左旋多巴疗法的许多治疗替代品正在测试中。其中，移植 来自胎儿供体或干细胞的未成熟DA神经元。这一做法继续 在概念上有吸引力，特别是对于晚期PD，其中依赖于剩余的可塑性的治疗， 神经元不太可能有效。与使用细胞植入物相关的主要问题是 移植后DA神经元存活不良和/或DA表型不稳定。过去 几年来，我们已经确定了几种分子，增加生存和功能的培养， 移植胎儿DA神经元。这些分子中的许多减轻了对DA的不同威胁的负面影响 神经元活力本提案的目标是系统地评估这些因素的组合， 制定一种疗法来优化移植的DA神经元的存活和功能。这种最佳方法将 允许减少治疗功效所需的细胞数量，改善移植物的标准化， 组合物和潜在地丰富与纹状体DA替代相关的DA神经元类型中的移植物。细胞 来自胎儿或干细胞来源的移植物含有中脑的主要DA神经元类型的混合物： A9型和A10型。最近的研究表明，只有A9型神经元能再支配纹状体 嫁接后。因此，我们对扩增效应的分析将集中在确定特定的 联合疗法特异性地富集相关A9细胞类型中的DA神经元群体。我们 先前的研究已经鉴定了以下分子在促进存活方面是单独有效的， 培养和移植的DA神经元的功能：SO 2A条件培养基（神经营养支持），血管 内皮生长因子（VEGF）（神经营养，刺激血管供应），褪黑激素（抗氧化剂），肌酸 （细胞能量）、促红细胞生成素（抗凋亡）和米诺环素（抗炎）。我们将使用一系列 在DA耗竭大鼠中利用细胞培养然后移植的实验， 促进移植的胎儿DA神经元和DA神经元中存活和稳定DA表型的方法 来源于人类胚胎干细胞。随着优化，细胞替代疗法可能成为一种 晚期PD的实用治疗选择。

Replacement of striatal dopamine (DA) remains the main goal of therapeutics for Parkinson's disease (PD). Many therapeutic alternatives to levodopa therapy are being tested. Among these is transplantation of immature DA neurons either derived from fetal donors or stem cells. This approach continues to be conceptually attractive, especially for late stage PD in which therapies that rely upon plasticity of remaining neurons are unlikely to be effective. The main problem associated with use of cell implants is the extremely poor survival of grafted DA neurons and/or the instability of DA phenotype after grafting. Over the past several years we have identified several molecules that augment survival and function of cultured and grafted fetal DA neurons. Many of these molecules ameliorate the negative impact of distinct threats to DA neuron viability. It is the goal of this proposal to systematically evaluate combinations of these factors to formulate a therapy to optimize survival and function of grafted DA neurons. Such an optimal approach will allow reduction in the number of cells required for therapeutic efficacy, improve standardization of graft composition and potentially enrich grafts in the DA neuron type relevant for striatal DA replacement. Cell grafts derived from fetal or stem cell sources contain a mixture of the major DA neuron types of the midbrain: A9 type and A10 type. It recently has been demonstrated that only A9 type neurons reinnervate the striatum after grafting. Thus, our analysis of augmentation effects will focus upon determining whether particular combination therapies specifically enrich the DA neuron population in the relevant A9 cell type. Our previous studies have identified the following molecules to be individually effective in promoting survival and function of cultured and grafted DA neurons: SO2A conditioned medium (neurotrophic support), vascular endothelial growth factor (VEGF)(neurotrophic, stimulates vascular supply), melatonin (anti-oxidant), creatine (cellular energy), erythropoeitin (anti-apoptotic), and minocycline (anti-inflammatory). We will use a series of experiments utilizing cell culture followed by grafting in DA-depleted rats to formulate a multi-factorial approach to promoting survival and stable DA phenotype in grafted fetal DA neurons and DA neurons derived from human embryonic stem cells. With optimization, cell replacement therapy could become a practical therapeutic option for late stage PD.