Albert Katrina, Voutilainen Merja H, Domanskyi Andrii, Airavaara Mikko
Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.
Genes (Basel). 2017 Feb 8;8(2):63. doi: 10.3390/genes8020063.
Gene delivery using adeno-associated virus (AAV) vectors is a widely used method to transduce neurons in the brain, especially due to its safety, efficacy, and long-lasting expression. In addition, by varying AAV serotype, promotor, and titer, it is possible to affect the cell specificity of expression or the expression levels of the protein of interest. Dopamine neurons in the substantia nigra projecting to the striatum, comprising the nigrostriatal pathway, are involved in movement control and degenerate in Parkinson's disease. AAV-based gene targeting to the projection area of these neurons in the striatum has been studied extensively to induce the production of neurotrophic factors for disease-modifying therapies for Parkinson's disease. Much less emphasis has been put on AAV-based gene therapy targeting dopamine neurons in substantia nigra. We will review the literature related to targeting striatum and/or substantia nigra dopamine neurons using AAVs in order to express neuroprotective and neurorestorative molecules, as well as produce animal disease models of Parkinson's disease. We discuss difficulties in targeting substantia nigra dopamine neurons and their vulnerability to stress in general. Therefore, choosing a proper control for experimental work is not trivial. Since the axons along the nigrostriatal tract are the first to degenerate in Parkinson's disease, the location to deliver the therapy must be carefully considered. We also review studies using AAV-a-synuclein (a-syn) to target substantia nigra dopamine neurons to produce an α-syn overexpression disease model in rats. Though these studies are able to produce mild dopamine system degeneration in the striatum and substantia nigra and some behavioural effects, there are studies pointing to the toxicity of AAV-carrying green fluorescent protein (GFP), which is often used as a control. Therefore, we discuss the potential difficulties in overexpressing proteins in general in the substantia nigra.
使用腺相关病毒(AAV)载体进行基因递送是一种广泛应用于转导大脑神经元的方法,特别是因其安全性、有效性和持久表达特性。此外,通过改变AAV血清型、启动子和滴度,可以影响目的蛋白的表达细胞特异性或表达水平。投射到纹状体的黑质多巴胺神经元,构成黑质纹状体通路,参与运动控制,在帕金森病中会发生退化。基于AAV的基因靶向这些神经元在纹状体中的投射区域已被广泛研究,以诱导产生神经营养因子用于帕金森病的疾病修饰治疗。基于AAV的针对黑质多巴胺神经元的基因治疗受到的关注则少得多。我们将综述与使用AAV靶向纹状体和/或黑质多巴胺神经元以表达神经保护和神经修复分子以及建立帕金森病动物疾病模型相关的文献。我们将讨论靶向黑质多巴胺神经元的困难以及它们一般对压力的易感性。因此,为实验工作选择合适的对照并非易事。由于沿黑质纹状体束的轴突在帕金森病中最先退化,所以必须仔细考虑治疗的递送位置。我们还将综述使用AAV - α - 突触核蛋白(α - syn)靶向黑质多巴胺神经元以在大鼠中产生α - syn过表达疾病模型的研究。尽管这些研究能够在纹状体和黑质中产生轻度多巴胺系统退化以及一些行为效应,但有研究指出携带绿色荧光蛋白(GFP)的AAV的毒性,而GFP常被用作对照。因此,我们将讨论在黑质中一般过表达蛋白的潜在困难。