AAV MEDIATED NEUROTROPHIC FACTOR GENE DELIVERY TO BRAIN

这项修订后的补助金的目标仍然是测试几个假设的亲神经因子体细胞基因转移到隔海马系统。 这些研究使用含有神经元特异性烯醇化酶（NSE）启动子的腺相关病毒（AAV）重组载体来驱动神经生长因子（NGF）或脑源性神经营养因子（BDNF）的表达。 初步研究表明，稳健的表达标记基因绿色荧光蛋白（GFP）在隔膜和海马的延长间隔后转导已扩展到观察营养因子的表达，胆碱能标记物和trk受体密度的水平在这条途径。 在研究的每个区域中表达是神经特异性的。 在海马中，神经元亚群也有一定程度的趋向性，但在隔区则不然。 我们的赠款计划测试：1）不同海马和隔区神经元中是否存在NSE驱动的GFP表达的剂量和时间依赖性表达：2）完整隔区和海马中BDNF和NGF的异位表达是否在不改变GABA能活性的情况下升高胆碱能和trk标记物;第三章如果将BDNF和NGF基因转移到隔中，则优先保护轴突切断的胆碱能神经元，其方式与海马中的任何类似基因转移都没有观察到或GABA能神经元：4）海马和隔区营养因子基因转移是否能改善穹窿部分损伤动物的记忆相关行为：5）隔区神经生长因子或脑源性神经营养因子基因转移是否能克服记忆相关行为和乙酰胆碱释放的年龄相关缺陷; 6）如果衰老对转基因NGF表达的干扰大于对BDNF表达的干扰，正如衰老过程中内源营养因子调节研究所预测的那样。 这些研究可能最终导致基因治疗试验与隔海马胆碱能缺陷，如阿尔茨海默氏病。

The goal of this revised grant continues to be testing several hypotheses about neurotropic factor somatic gene transfer into the septohippocampal system. These studies use adeno-associated virus (AAV) recombinant vectors containing the neuron specific enolase (NSE) promoter to drive expression of nerve growth factor (NGF) or brain derived neurotrophic factor (BDNF). Initial studies demonstrating robust expression of the marker gene green fluorescent protein (GFP) in septum and hippocampus for extended intervals after transduction have been extended to observations about trophic factor expression, levels of cholinergic markers and trk-receptor density in this pathway. Expression is neuro-specific in each region studied. Some degree of tropism for subpopulations o neurons is also apparent in hippocampus, though not so in septum. Our grant proposes to test: 1) whether there are dose- and time-dependent expressions of NSE-driven GFP expression in different hippocampal and septal neurons: 2) if ectopic BDNF and NGF expression in intact septum and hippocampus elevates cholinergic and trk markers without altering GABAergic activity; 3) if BDNF and NGF gene transfer into septum preferentially protects axotomized cholinergic neurons in a manner not seen with either similar gene transfer in hippocampus or with GABAergic neurons: 4) whether both hippocampal and septal trophic factor gene transfer can improve memory-related behaviors in animals receiving partial fornix lesions; 5) whether age-related deficits in memory-related behaviors and acetylcholine release can be overcome with septal NGF or BDNF gene transfer; and 6) if aging interferes with the expression of transgenic NGF more than that of BDNF, as predicted from studies of endogenous trophic factor regulation during senescence. These studies may lead eventually to gene therapy trials for conditions associated with septohippocampal cholinergic deficits such as Alzheimer's disease.