PRESSURE REGULATION OF HUMAN TRABECULAR MESHWORK GENES

人类小梁网基因的压力调节

• 批准号: 6702361
• 负责人: Teresa Borras
• 金额: $ 22.13万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6702361
• 关键词: extracellular matrix; free radical oxygen; gene expression; gene induction /repression; genetic library; genetic regulation; homeostasis; human tissue; interleukin 6; intraocular aqueous flow; intraocular pressure; microarray technology; nucleic acid hybridization; organ culture; polymerase chain reaction; postmortem; substance P; trabecular meshwork; transfection /expression vector

Cells of the human trabecular meshwork (TM) are constantly exposed to fluid mechanical forces generated by the intraocular pressure/flow of aqueous humor. Exposure to these forces can modulate the expression of many genes involved in aqueous humor physiology and pathophysiology. Elevated intraocular pressure (IOP), present in most forms of glaucoma, is known to affect structure and function of the TM. After 6 h elevated IOP, we found eleven genes to be consistently up-regulated in the human TM: interleukin-6, preprotachykinin-1, secretogranin-II, cathepsin-L, stromelysin-1, thymosin-beta4, alpha-tubulin, alphaB-crystallin, glyceraldehyde-3-phosphate dehydrogenase, metallothionein and Cu/Zn superoxide dismutase. The gene encoding TIGR/MYOC was up-regulated after 7 days. Our general hypothesis is that regulation of IOP is governed in part by the coordinated expression of TM genes. Specifically, we hypothesize that early response to elevated IOP would induce genes involved in maintaining homeostatic mechanisms of outflow regulation whereas sustained elevation of IOP would induce genes whose adverse products would be associated with pathological mechanisms. Finally, we hypothesize that the products of genes induced at 6 h predict mechanisms regulating outflow resistance that might be similar to those regulating vascular permeability. To test these hypotheses we propose to identify human TM/Schlemm's canal (SC) genes that are differentially expressed after 1 h, 48 h and 7 days exposure to an elevated pressure insult. We also propose to examine mechanisms of cellular permeability in human outflow cells and organ cultures under conditions of elevated pressure and over/under expression of selected genes. Our strategy includes perfused human anterior segment cultures, exponential amplification libraries, high- density cDNA arrays and adenoviral technology. This approach provides adequate mechanical stimulus (pressure drop), genetic homogeneity (paired eyes), libraries with small amounts of tissue and efficient gene delivery system. Even if some of the selected genes or mechanisms would appear to be not of primary relevance on the regulation of IOP, the identification of human TM/SC genes in the arrays will provide important new information on the coordinated gene expression of the outflow system under mechanical stress.

人类小梁网 (TM) 的细胞不断暴露于由眼内压/房水流动产生的流体机械力。 暴露于这些力可以调节涉及房水生理学和病理生理学的许多基因的表达。 大多数青光眼中都存在眼压升高 (IOP)，已知它会影响 TM 的结构和功能。 眼压升高 6 小时后，我们发现人类 TM 中有 11 个基因持续上调：白介素-6、前原速激肽-1、分泌颗粒素-II、组织蛋白酶-L、基质溶解素-1、胸腺素-β4、α-微管蛋白、αB -晶状体蛋白、3-磷酸甘油醛脱氢酶、金属硫蛋白和铜/锌超氧化物歧化酶。 7天后编码TIGR/MYOC的基因上调。我们的一般假设是 IOP 的调节部分由 TM 基因的协调表达控制。 具体来说，我们假设对眼压升高的早期反应将诱导参与维持流出调节稳态机制的基因，而眼压持续升高将诱导其不良产物与病理机制相关的基因。 最后，我们假设 6 小时诱导的基因产物预测了调节流出阻力的机制，该机制可能类似于调节血管通透性的机制。为了检验这些假设，我们建议鉴定人类 TM/施累姆氏管 (SC) 基因，这些基因在暴露于高压损伤 1 小时、48 小时和 7 天后差异表达。 我们还建议检查在高压和选定基因过度/不足表达的条件下人类流出细胞和器官培养物的细胞通透性机制。 我们的策略包括灌注人类眼前节培养物、指数扩增文库、高密度 cDNA 阵列和腺病毒技术。 这种方法提供了足够的机械刺激（压降）、遗传同质性（配对眼睛）、具有少量组织的文库和高效的基因传递系统。即使某些选定的基因或机制似乎与 IOP 的调节不具有主要相关性，阵列中人类 TM/SC 基因的鉴定也将提供有关机械条件下流出系统协调基因表达的重要新信息。压力。