The Neuroprotective Effect of HSP72 Induction in Experimental Glaucoma

描述（由申请人提供）：我们研究的长期目标是开发一种神经保护策略，以补充目前青光眼降低IOP的治疗。我们的假设是，长期药物诱导Hsp72（热休克蛋白70的诱导形式）表达可以保护RGCs免受青光眼损伤。这一假设是基于HSP72广泛的细胞保护能力，这可能是由于它能够抑制几种凋亡途径。该建议的具体目标是：目标1。确定Hsp72过表达对青光眼模型大鼠RGC存活的影响。携带HSP72基因（AAV-HSP72）的腺相关病毒（AAV，血清型5）载体将用于在RGCs中传递和表达相应的蛋白，这是神经保护的主要目标。HSP72在青光眼视网膜中的特异性过表达将使我们能够评估其神经保护作用。目标2。阐明HSP72抑制实验性青光眼细胞凋亡通路的机制。已知HSP72可抑制多种导致细胞死亡的途径，其抗凋亡功能与凋亡蛋白酶激活因子-1 （Apaf-1）、凋亡诱导因子（AIF）和c-Jun n -末端激酶（JNK）的结合有关。HSP72对实验性青光眼的RGC保护的参与以及其他可能的机制将被进一步研究。这些研究结果将有助于我们明确HSP72的神经保护机制，更好地了解青光眼RGC凋亡。目标3。评价HSP72药物诱导治疗青光眼的潜力。我们将研究GGA和阿利莫洛尔作为HSP72共诱导剂，在大鼠青光眼模型中作为保护RGCs的潜在治疗药物。HSP72在GGA和阿利莫洛尔介导的神经保护中的作用将通过设计用于降解HSP72 mRNA的小干扰RNA （siRNA）抑制HSP72的表达来分析。本研究旨在全面评价Hsp72在实验性青光眼中的神经保护作用，了解其在凋亡通路中的作用机制。我们认为，HSP72的细胞保护和抗凋亡特性以及在应激细胞中诱导该蛋白表达的可能性使其成为青光眼神经保护的一个有吸引力的治疗靶点。HSP72保护细胞免受各种应激刺激的能力是设计保护青光眼RGCs策略的重要因素，因为这种疾病的细胞损伤可能由不同的分子机制引起，这些分子机制具有共同的最终途径，即特征性视神经损伤和视力丧失。公共卫生相关性：视网膜神经节细胞（RGCs）变性是青光眼视力丧失的主要原因，全世界有7000多万人受其影响。本研究的主要目的是评价无毒药物诱导热休克蛋白72 （HSP72）对青光眼动物的RGC保护作用。众所周知，这种蛋白质可以保护不同类型的细胞，包括神经细胞，免受各种损害。我们的研究结果可能为考虑将HSP72诱导剂作为青光眼的潜在神经保护药物提供治疗支持。

DESCRIPTION (provided by applicant): The long-term objective of our research is to develop a neuroprotective strategy that will complement the current treatment of glaucoma with IOP reduction. Our hypothesis is that long-term pharmacological induction of Hsp72 (the inducible form of heat shock protein 70) expression can protect RGCs from glaucomatous damage. This hypothesis is based on the wide range of cytoprotective capacities of HSP72, which may be explained by its ability to inhibit several apoptotic pathways. Specific aims of the proposal are: Aim 1. Determine the effect of Hsp72 overexpression on RGC survival in a rat glaucoma model. Adeno- associated viral (AAV, serotype 5) based vectors carrying the HSP72 gene (AAV-HSP72) will be used to deliver and express the corresponding protein in RGCs, which is the primary target for neuroprotection. Specific overexpression of HSP72 in glaucomatous retinas will allow us to evaluate its neuroprotective effect. Aim 2. Elucidate the mechanisms of inhibition of apoptotic pathways by HSP72 in experimental glaucoma. HSP72 is known to inhibit multiple pathways leading to cell death and its anti-apoptotic functions are associated with binding to apoptosis protease activating factor-1 (Apaf-1), apotosis-inducing factor (AIF) and c-Jun N-terminal kinase (JNK). The involvement of these and other potential mechanisms of RGC protection by HSP72 in experimental glaucoma will be studied. The results of these studies will help us define HSP72 neuroprotective mechanisms and better understand RGC apoptosis in glaucoma. Aim 3. Evaluate the therapeutic potential of pharmacological induction of HSP72 for glaucoma. We will study GGA and arimoclomol, HSP72 co-inducers, as potential therapeutic agents for protection of RGCs in the rat glaucoma model. The role of HSP72 in GGA and arimoclomol mediated neuroprotection will be analyzed by inhibition of HSP72 expression with small interfering RNA (siRNA) designed to degrade HSP72 mRNA. The proposal is intended to comprehensively evaluate the Hsp72 neuroprotective effect in experimental glaucoma and understand the mechanisms of its action on apoptotic pathways. We believe that the cytoprotective and anti-apoptotic characteristics of HSP72 and the possibility to pharmacologically induce expression of this protein in cells experiencing stress make this protein an attractive therapeutic target for glaucoma neuroprotection. The ability of HSP72 to protect cells from a variety of stress stimuli is an important factor in designing a strategy to preserve RGCs in glaucoma, since the cellular damage in this disease may be caused by different molecular mechanisms that have a common final pathway of characteristic optic nerve damage and visual loss. PUBLIC HEALTH RELEVANCE: The degeneration of retinal ganglion cells (RGCs) is the primary cause of visual loss in glaucoma, which affects more than 70 million people worldwide. The main aim of the proposed study is the evaluation of the heat shock protein 72 (HSP72) induction with non-toxic drugs in RGC protection in animals with glaucoma. This protein is known to protect different types of cells, including neuronal cells, against various insults. The results of our studies may provide support for therapeutic consideration of HSP72 inducers as potential neuroprotective drugs for glaucoma.