Gene Therapy, Stress and Hippocampal Function

描述(申请人提供)：已经研究了海马体的突触可塑性，在认知中的作用，以及发生在成人海马体中的神经发生。随之而来的是对海马体功能的内分泌调节器的欣赏。具体地说，糖皮质激素(GC)，应激期间分泌的肾上腺类固醇，破坏[或]损害突触可塑性和认知方面，并抑制神经发生。相比之下，雌激素可以增强可塑性、认知能力和神经发生。在使用病毒载体向中枢神经系统运送转基因方面也取得了进展。我们将在基因治疗策略中使用单纯疱疹病毒1载体来保护海马体免受GC和应激的干扰，并将其中一些GC效应转移到有益的雌激素效应。我们已经构建并希望探索表达a)降解GC的酶；b)显性的负GC受体；c)与GC结合但具有雌激素受体的基因组作用的嵌合类固醇受体的保护潜力。在目标1中，我们将改变这些载体，使它们可以被压力和GC诱导，作为一种手段，使它们的表达被侮辱触发。然后，我们将描述它们的表达方式。然后，我们将检查这些载体的保护潜力，检查前两个备用神经元是否免受不良GC效应的影响，以及嵌合载体在暴露于GC时是否也产生有益的雌激素效应。在目标2中，终点将是来自不同死前GC暴露或应激制度的大鼠产生的海马片的长期增强。在目标3中，我们将研究GC、应激和这些载体对海马区依赖的认知任务的影响。在目标4中，我们将研究体外和成人海马区的神经发生。我们将描述糖皮质激素、应激和雌激素对它的影响。然后，我们将确定这些载体是否可以保护神经发生免受GC的抑制作用，并且在嵌合载体的情况下，利用这一点来产生刺激性雌激素效应。

DESCRIPTION (provided by applicant): The hippocampus has been studied for its synaptic plasticity, role in cognition, and the neurogenesis that occurs in the adult hippocampus. With this has come an appreciation of endocrine modulators of hippocampal function. Specifically, glucocorticoids (GCs), adrenal steroids secreted during stress, disrupt [or] impair facets of synaptic plasticity and cognition, and inhibit neurogenesis. Estrogen, in contrast, enhances plasticity, cognition and neurogenesis. There has also been progress in the use of viral vectors to deliver transgenes into the CNS. We will use herpes simplex virus-1 vectors in a gene therapy strategy to protect the hippocampus from the disruptive effects of GCs and of stress, and to divert some of those GC effects into salutary estrogenic ones. We have constructed and wish to explore the protective potential of vectors expressing a) an enzyme which degrades GCs; b) a dominant negative GC receptor; c) a chimeric steroid receptor which binds GCs but has the genomic actions of an estrogen receptor. In Aim 1, we will alter these vectors to make them inducible by stress and GCs, as a means to have their expression triggered by insults. We will then characterize their patterns of expression. We will then examine the protective potential of these vectors, examining if the first two spare neurons from adverse GC effects, and if the chimeric vector also generates the salutary estrogenic effects when exposed to GCs. In Aim 2, the endpoint will be long-term potentiation in hippocampal slices generated from rats with differing pre-mortem regimes of GC exposure or stress. In Aim 3, we will study the effects of GCs, stress, and these vectors upon a hippocampal-dependent cognitive task. In Aim 4, we will study neurogenesis in vitro and in the adult hippocampus. We will characterize the effects of GCs, stress and estrogen upon it. We will then determine whether these vectors can protect neurogenesis from the inhibitory effects of GCs and, in the case of the chimeric vector, harness this to produce stimulatory estrogenic effects.