Requirement for Glucocorticoids for Adipogenesis in vivo.

体内脂肪生成对糖皮质激素的需求。

• 批准号: 8280390
• 负责人: Charles A Harris
• 金额: $ 4.9万
• 依托单位: J. DAVID GLADSTONE INSTITUTES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8280390
• 关键词: 3T3-L1 Cells; Address; Adipocytes; Adipose tissue; Birth; Cell Line; Cell Transplants; Cells; Cues; Cyclic AMP; Dexamethasone; Diabetes Mellitus; Embryo; Environment; Epidemic; Fatty acid glycerol esters; Fibroblasts; Glucocorticoid Receptor; Glucocorticoids; Histology; Hormonal; Image; In Vitro; Insulin; Insulin Resistance; Knockout Mice; Learning; Ligands; Light; Lipids; Literature; Luciferases; Modeling; Mus; Non-Insulin-Dependent Diabetes Mellitus; Obesity; Outcome; Pathogenesis; Peroxisome Proliferator-Activated Receptors; Phosphodiesterase Inhibitors; Process; Property; Role; Signal Transduction; Stem cell transplant; Stem cells; Techniques; Testing; Transplantation; adipocyte differentiation; cell type; in vivo; in vivo Model; interest; lipid biosynthesis; molecular marker; non-invasive monitor; receptor; transcription factor

DESCRIPTION (provided by applicant): Both excess adipose tissue and insufficient adipose tissue result in insulin resistance and diabetes. Therefore understanding the processes by which adipocytes form is of great interest. Much of what we have learned of this process has come from 30 years of analysis of 3T3-L1 cells differentiating in vitro when given an adipogenic cocktail of dexamethasone (glucocorticoid), IBMX (raises intracellular cAMP levels) and insulin. This cocktail has been shown to induce adipogenic transcription factors such as C/EBPs and PPAR-3. These transcription factors have been shown to be required for adipogenesis in vivo in mice, but the cues that induce them in vivo during adipogenesis are unknown. There is evidence from the literature to suggest that the cues for adipogenesis in vivo may differ from those used in vitro. For example, mouse embryonic fibroblasts from lipoatrophic mice with no fat differentiate competently into lipid-laden adipocytes. It is not possible to assess the requirement for GR in adipogenesis in GR-null mice because they die at birth prior to adipogenesis in vivo. To address this problem this proposal will use transplantation of adipose stem cells in mice. Aim 1 To establish a model of adipose stem cell transplantation to study adipogenesis in vivo. An array of potential adipogenic stem cell types (from mice with the unique property of activating luciferase upon forming adipocytes) will be transplanted into host mice. Aim 2 To determine the requirement for glucocorticoids in adipogenesis in vivo. Adipogenic stem cells will be transplanted into adrenalectomized or control host mice. Adipogenesis will be assessed by bioluminescent in vivo imaging. Aim 3 To determine the role of GR in adipogenesis in vivo. Adipogenic cells that are GR-null or GR-wildtype control will be transplanted into host mice and their potential to undergo adipogenesis assessed by molecular markers and histology. These Aims should answer the question as to whether glucocorticoid ligand and receptor are required for adipogenesis in vivo.

描述（由申请人提供）：过量的脂肪组织和脂肪组织不足会导致胰岛素抵抗和糖尿病。因此，了解脂肪细胞形成的过程引起了极大的兴趣。我们了解了这一过程的大部分内容来自30年的分析3T3-L1细胞，当给予地塞米松（糖皮质激素），IBMX（提高细胞内营地）和胰岛素的脂肪鸡尾酒时，在体外区分了体外。该鸡尾酒已被证明会诱导掺杂转录因子，例如C/EBP和PPAR-3。这些转录因子已被证明是小鼠体内脂肪形成所必需的，但是在掺杂过程中诱导它们的体内的提示尚不清楚。文献中有证据表明，体内脂肪形成的提示可能与体外使用的线索不同。例如，来自无脂肪的脂肪小鼠的小鼠胚胎成纤维细胞有效地分化为富含脂质的脂肪细胞。无法评估Gr-null小鼠脂肪形成中GR的需求，因为它们在体内脂肪形成之前在出生时死亡。为了解决这个问题，该建议将使用小鼠中脂肪干细胞的移植。目标1建立脂肪干细胞移植模型以研究体内脂肪形成。一系列潜在的脂肪形成干细胞类型（来自具有激活荧光素酶在形成脂肪细胞时具有独特特性的小鼠）将被移植到宿主小鼠中。目标2以确定体内脂肪形成中糖皮质激素的需求。脂肪生成干细胞将被移植到肾上腺切除术或对照宿主小鼠中。脂肪形成将通过体内成像的生物发光评估。目标3确定GR在体内脂肪形成中的作用。 GR-NULL或GR-WILDTYPE控制的成脂细胞将被移植到宿主小鼠中，并通过分子标记和组织学评估的脂肪形成潜力。这些目标应回答有关糖皮质激素配体和受体是否需要体内脂肪形成的问题。