LOUISIANA COBRE: P3: PPARGAMRNA IN HUMAN ADIPOSE TISSUE DERIVED ADULT STEM CELL

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。肥胖是2型糖尿病、代谢综合征和高血压等心血管疾病的主要危险因素。脂肪组织表达高水平的过氧化物酶体增殖物激活受体，PPARgamma，脂肪细胞形成的主开关。最近的研究表明，PPARgamma水平的调节可改善胰岛素敏感性，并防止与衰老相关的胰岛素抵抗。我们的研究表明，通过泛素-脯氨酸酶体系统对PPARgamma水平的调节与PPARgamma活性的控制有关。此外，我们还了解到，泛素样蛋白SUMO-1对N末端AF-1结构域中的PPARgamma的修饰会影响PPARgamma的稳定性和活性。这些研究表明，泛素和泛素样蛋白对PPARgamma活性的调节在脂肪形成和肥胖的发展中起重要作用。然而，这些研究使用了鼠3 T3-L1脂肪细胞系，并且有证据表明鼠和人系统之间的脂肪形成可能不同。在这项研究中，我们建议开始的PPARgainma活性和泛素-蛋白酶体依赖性降解之间的关系，使用成人干细胞分离的人吸脂吸出物。这些原代细胞培养物被鉴定为脂肪来源的成体干细胞（ADAS），是可以被可重复地诱导以经历脂肪生成的丰富资源。我们将采用这种原代细胞培养系统，以研究PPARgamma活性和ubiquitindependent营业额之间的关系，在人类为基础的，临床相关的细胞系。我们假设泛素依赖性降解是PPARgamma活性的重要调节因子，并且PPARgamma在人ADAS衍生的脂肪细胞中也被SUMO-1修饰。具体目标1将集中于检查基础和配体激活条件下PPARgamma的泛素化和SUMO化状态。具体目标2将侧重于检查源自皮下和内脏脂肪库的脂肪细胞中的PPARgamma周转。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Obesity is a primary risk factor for type 2 diabetes, metabolic syndrome and cardiovascular diseases such as hypertension. Adipose tissues express high levels of the peroxisome proliferator-activated receptor, PPARgamma, the master switch in adipose cell formation. Recent studies show that modulation of PPARgamma levels improves insulin sensitivity and protects against insulin resistance associated with aging. Our studies indicate that regulation of PPARgamma levels by the ubiquitin-proleasome system is linked to control of PPARgamma activity. In addition, we have learned that modification of PPARgamma in the Nterminal AF-1 domain by the ubiquitin-like protein, SUMO-1, affects PPARgamma stability and activity. These studies suggest that modulation of PPARgamma activity by ubiquitin and ubiquitin-like proteins plays an important role in adipogenesis and the development of obesity. However, these studies have used the murine 3T3-L1 adipocyte cell line and there is evidence that adipogenesis may differ between muririe and human systems. In this study, we propose to begin characterizing the relationship between PPARgainma activity and ubiquitin-proteasome-dependent degradation using adult stem cells isolated from human liposuction aspirates. These primary cell cultures, identified as Adipose Derived Adult Stem (ADAS) cells, are an abundant resource that can be reproducibly induced to undergo adipogenesis. We will employ this primary cell culture system to examine the relationship between PPARgamma activity and ubiquitindependent turnover in a human-based, clinically relevant cell line. We hypothesize that ubiquitin-dependent degradation is an important regulator of PPARgamma activity and that PPARgamma is also modified by SUMO-1 in the human ADAS-derived adipocyte. Specific aim 1 will focus on examining the ubiquitylation and SUMOylation status of PPARgamma under basal and ligand-activated conditions. Specific aim 2 will focus on examining PPARgamma turnover in adipocytes derived from subcutaneous and visceral fat depots.