P311 mediated adipogenesis, adipocyte plasticity and metabolic regulation

摘要 三分之一的美国人临床上患有肥胖症，这种情况会增加患慢性病的风险，比如 2型糖尿病(DM)、心脏病和癌症。脂肪细胞功能障碍(AD)是糖尿病的主要特征 代谢失调，增加患胰岛素抵抗(IR)、糖尿病和高血压的风险。 在脂肪细胞肥大的同时，白色脂肪组织的巨噬细胞浸润(WAT)与 肥胖、阿尔茨海默病和胰岛素抵抗的病理生理学，尽管潜在的分子机制尚不清楚。我们 首先在WAT、棕色脂肪组织(BAT)和米色脂肪组织中发现了P311的存在。这个 P311基因敲除(KO)小鼠的WAT驻留巨噬细胞减少，细胞动力学降低， 包括自噬和细胞凋亡的减少。这可能会导致脂肪细胞肥大，进而 由于年龄和遗传消融介导的P311表达导致高血糖，导致过度工作和 耗竭性脂肪细胞P311KO或低表达P311的脂肪细胞与野生型比较。就像研究一样 一项新的研究表明，在脂肪组织发育的早期，有限的驻留巨噬细胞可以改变脂肪细胞的功能 需要探索的机制。我们还将探索脂肪细胞的关键细胞凋亡过程和 自噬/脂噬，这可能影响P311 KO小鼠体内脂肪细胞的周转，导致脂肪细胞 肥大和功能障碍，因此代谢失调。 拟议中的项目将测试年龄和遗传消融介导的P311水平发挥作用的中心假设 在白色、棕色和米色脂肪细胞的发育、可塑性和功能以及代谢中起关键作用 监管。此外，我们将研究P311在细胞过程中的作用(即Wat棕色和BAT 美白)及其对脂肪细胞功能和血糖控制的影响，因为P311 KO小鼠是高血糖的。我们 还将评估P311通过PPAR和PPAR调节脂肪生物学和代谢调节的能力 UCP1的调控，以及myo1C与GLUT4的结合。我们将培育脂肪细胞特异性的P311 KO条件性小鼠 使用新的CRISPR技术评估脂肪细胞特异性P311的作用。因此，当前项目将 使P311成为脂肪细胞生物学和代谢调节的新参与者。我们的试验性策略将 使用经典的细胞生物学、分子生物学、生化、免疫分析和 影像方法研究。我们的发现将加深对P311介导的脂肪细胞发育的理解 和功能及脂肪体积的膨胀。我们正在进行的研究表明，P311可能调节新陈代谢 通过脂肪细胞的动力学、功能和可塑性(一种通过 水的褐变)；调节驻留和渗透的巨噬细胞；以及控制脂肪细胞 流程。这些研究是新的，与现有资金没有重叠。

Summary One third of the US population is clinically obese, a condition which increases the risk for chronic diseases like type 2 diabetes mellitus (DM), heart disease and cancers. Adipocyte dysfunction (AD) is cardinal feature of metabolic dysregulation and increases the risk for developing insulin resistance (IR), DM, and hypertension. Along with adipocyte hypertrophy, macrophage infiltration of white adipose tissue (WAT) is associated with the pathophysiology of obesity, AD and IR, albeit the underlying molecular mechanisms are uncharacterized. We were first to show the presence of P311 in WAT, brown adipose tissue (BAT) and beige adipose tissue. The WAT of P311 knockout (KO) mice has fewer resident macrophages and decreased cellular dynamics, including decreased autophagy and apoptosis. This is potentially leading to adipocyte hypertrophy that in turn causes hyperglycemia due to age- and genetic ablation-mediated P311 expression leading to overworked and exhausted adipocytes in P311 KOs or low P311 expressing adipocytes compared to wild types. As studies are limited, resident macrophages could alter adipocyte function early in adipose tissue development, a novel mechanism requiring exploration. We will also explore key adipocyte cellular processes of apoptosis and autophagy/lipophagy, which may affect adipocyte turnover in the WAT of P311 KO mice, leading to adipocyte hypertrophy and dysfunction, and thus metabolic deregulation. The proposed project will test the central hypothesis that age- and genetic ablation-mediated P311 levels play a key role in white, brown and beige adipocyte development, plasticity and function, as well as in metabolic regulation. Further, we will investigate the role of P311 in cellular processes (i.e., WAT browning and BAT whitening) and its effect on adipocyte function and glycemic control, as P311 KO mice are hyperglycemic. We will also evaluate the ability of P311 to modulate adipose biology and metabolic regulation through PPAR and UCP1 regulation; and myo1C binding to GLUT4. We will develop adipocyte-specific P311 KO conditional mice using novel CRISPR technology to evaluate the adipocyte-specific P311 roles. The current project will thereby establish P311 as a new player in adipocyte biology and metabolic regulation. Our experimental strategy will incorporate transgenic animals using classic cell biology, molecular biology, biochemical, immunoassays and imaging methods studies. Our findings will enhance the understanding of P311 mediated fat cell development and function and fat mass expansion. Our ongoing studies indicate that P311 potentially regulates metabolism through adipocyte dynamics, function and plasticity (a novel approach to targeting metabolic disorders through browning of WAT); regulating resident and infiltrating macrophages; and controlling adipocyte cellular processes. These studies are new and do not overlap with existing funding.