MOLECULAR DISSECTION OF REGIONAL ADIPOSITY

描述（由申请人提供）：肥胖是一个日益严重的国家健康问题，它与心血管疾病和糖尿病的合并症密切相关。基于人口的研究表明，多余脂肪组织的区域位置与健康影响之间存在很强的关联，其中腹内内脏肥胖导致最有害的影响。对人类和啮齿动物的研究表明，每个白色脂肪组织（WAT）贮库具有独特的生理和代谢特征。然而，这些表型差异背后的基因表达模式已经接受了非常有限的研究，并且还没有描述具有来自一个或另一个特定WAT贮库的脂肪细胞特有表达的基因。为了解决每个WAT贮库在转录上不同的假设，我们制备并差异筛选了小鼠WAT贮库消减文库，并进行了先导性滤膜DNA阵列杂交研究。使用小鼠作为模型系统，R21提案中的研究进一步描述了在四个不同的WAT库-网膜、皮下、附睾和腹膜后中发现的来自野生型和肥胖来源的脂肪细胞之间的基因表达差异。这些转录谱将产生关键的见解如何在不同的WAT仓库脂肪细胞的基因表达差异导致局部肥胖的病理生理。将有两个具体目标：（1）。利用DNA微阵列，消减克隆，和差异显示，我们将表征的白色脂肪细胞库特异性基因表达的配置文件。2.）将生成并验证用于WAT储库特异性基因表达高通量研究的体外细胞培养模型。本研究的长期目标是鉴定在体内WAT贮库特化和基因表达中起作用的DNA元件及其同源转录因子。这些知识将用于定义导致局部肥胖的病理生理学和共病的分子机制，并设计WAT库特异性启动子构建体以进行靶向消融研究。只有通过这种方式，才能在体内评估和调节特定WAT仓库对健康和疾病的贡献;使用当前的分子工具进行此类实验是不可行的。完成R21提案中的研究计划将是实现这些长期目标的关键一步。

DESCRIPTION (provided by applicant): Obesity is a growing national health concern and it is closely linked to comorbidities of cardiovascular disease and diabetes. Population-based studies have indicated a strong association between regional location of excess adipose tissue and health impact, with intra-abdominal visceral adiposity resulting in the most deleterious effects. Studies in humans and rodents indicate that each white adipose tissue (WAT) depot has unique physiological and metabolic profiles. However, the gene expression patterns underlying these phenotypic distinctions have received very limited study and no gene with expression exclusive to adipocytes from one or another particular WAT depot has been described. To address the hypothesis that each WAT depot is transcriptionally distinct, we have prepared and differentially screened a murine WAT depot subtracted library and conducted pilot filter DNA array hybridization studies. Using the mouse as a model system, studies in this R21 proposal further delineate the gene expression differences between adipocytes found in each of four distinct WAT depots - omental, subcutaneous, epididymal and retroperitoneal from wild type and obese sources. These transcriptional profiles will yield critical insights into how differences in gene expression of adipocytes in various WAT depots lead to pathophysiology of regional adiposity. Two specific aims will be conducted: 1.) Utilizing DNA microarray, subtracted cloning, and differential display, we will characterize profiles of white adipocyte depot-specific gene expression. 2.) In vitro cell culture models for the high throughput study of WAT depot specific gene expression will be generated and validated. The long-term goal of this research is to identify DNA elements and their cognate transcription factors that function in WAT depot specification and gene expression in vivo. This knowledge will be used to define the molecular mechanisms that result in pathophysiology and co-morbidities of regional obesity and to design WAT depot-specific promoter constructs to conduct targeted ablation studies. Only in this way can the contribution of a particular WAT depot to health and disease be assessed and modulated in vivo; such experiments are not feasible with current molecular tools. The completion of the research plan in this R21 proposal will be a critical step in achieving these long-term goals.