Protective Effects of Stearic Acid on Gestational and Acquired Diabetes Mellitus

描述(申请人提供)：假设。这一建议的中心假设是CD36、ABCD2和mitoNEET介导了硬脂酸对妊娠期糖尿病和后代获得性糖尿病的保护作用。基本原理。这项建议的目的是验证新的假设，即硬脂酸通过CD36、ABCD2和mitoNEET三种蛋白质改善妊娠期糖尿病(GDM)母亲的后代以及随后的糖尿病。我们将使用在怀孕16天左右发育成GDM的CSTBLKS/J-Lep/*‘*小鼠。我们将研究硬脂酸对妊娠期糖尿病患者CD36、ABCD2和mitoNEET表达和功能的影响机制，以及对db/+DAMs子代的长期代谢和心血管结局的影响。最后，我们将使用每种蛋白质的单独基因敲除模型来确定每种蛋白质在GDM和后代糖尿病中介导硬脂酸作用的程度。这种方法的独特性和潜在的临床相关性是对一种可能的方法的机制分析，该方法既可以治疗妊娠期糖尿病，也可以治疗后代获得的继发性糖尿病。我们提出的体内研究可以通过分离组织和细胞的体外研究来进一步剖析，这将使我们能够深入探讨硬脂酸的保护作用机制。1.探讨硬脂酸对妊娠期糖尿病发生发展及程度的影响。DB/+DAMS将用于通过测量口服葡萄糖耐量、血管反应性和脂肪细胞功能来检查硬脂酸是否影响GDM的发展。CD36、ABCD2和mitoNEET在脂肪中的表达和亚细胞定位将通过脂肪酸生物化学(p-氧化、脂肪酸组成和血管紧张素II分泌)的测量来量化和评估蛋白质的功能。类似地，我们还将检查只喂给db/+DAMs的硬脂酸治疗对后代糖尿病程度的影响。最后，我们将深入研究硬脂酸对胰岛素抵抗3T3-L1脂肪细胞脂肪酸生化的作用机制。这一目标很重要，因为我们将机械地评估对妊娠期糖尿病及其后代伴随的糖尿病的潜在姑息干预。2.确定硬脂酸改善db/db小鼠糖尿病表型的持续时间。Db/db子代将用硬脂酸处理，并调查保护作用的持续时间和程度。此外，还将研究停用硬脂酸对干预的持久效益的影响。我们将测量血压、血管反应性、体重和血糖。我们将通过测定CD36、ABCD2和mitoNEET在脂肪中的表达和亚细胞定位，并通过脂肪脂肪酸生化测量来评估每种蛋白质的功能，来研究硬脂酸的作用机制。这一目标很重要，因为它将提供关于硬脂酸干预的心血管益处和可持续性的数据。3.确定硬脂酸的有益作用是否由CD36、ABCD2和/或mitoNEET介导。我们将CD36、ABCD2或mitoNEET缺失的小鼠与db/+小鼠杂交，评估硬脂酸在改善GDM以及随后缺乏每个单独基因的双杂交db/db后代的糖尿病表型方面的有效性。我们将在db/+dam中测量OGTT、血管反应性和脂肪脂肪酸生化。此外，我们将评估单个基因敲除对硬脂酸影响db/db小鼠糖尿病发展的能力的影响。这将通过测量体重、血糖、胰岛素、血压和血管反应性来实现。从机理上讲，基因消融的影响将通过对分离的初级脂肪生物化学的综合分析来剖析。这一目标是至关重要的，因为每个双杂交小鼠品系都将提供关于每种蛋白质在调节硬脂酸有益效果中所起作用的明确的机制数据。

DESCRIPTION (provided by applicant): Hypothesis. The central hypothesis of this proposal is that CD36, ABCD2, and mitoNEET mediate the protective effects of stearic acid on gestational diabetes and on the acquired diabetes of the progeny. Rationale. The goal of this proposal is to test the novel hypothesis that stearic acid ameliorates gestational diabetes mellitus (GDM) and subsequent diabetes in the progeny of GDM mothers through a triad of CD36, ABCD2, and mitoNEET proteins. We will use the CSTBLKS/J-Lep/*'* mouse that develops GDM around day 16 of gestation. We will examine the mechanisms of stearic acid on CD36, ABCD2, and mitoNEET expression and function in both GDM and on long-term metabolic and cardiovascular outcomes in the progeny of the db/+ dams. Finally, we will use individual genetic knockout models for each protein to determine the extent to which each protein mediates the action of stearic acid in both GDM and diabetes of the progeny. The uniqueness and potential clinical relevance of this approach is the mechanistic analysis of a possible means for treatment of both GDM and pursuant diabetes mellitus acquired by the offspring. We propose in vivo studies that can be further dissected by in vitro studies with isolated tissues and cells, which will enable us to thoroughly explore the protective mechanism of action of stearic acid. 1. To determine the impact of stearic acid on the development and extent of GDM. Db/+ dams will be used to examine whether stearic acid affects the development of GDM by measuring oral glucose tolerance, vascular responsiveness, and adipocyte function. The expression and subcellular localization of CD36, ABCD2, and mitoNEET in adipose will be quantified and functionality of the proteins assessed through measurements of fatty acid biochemistry (p-oxidation, fatty acid composition, and angiotensin II secretion). Similarly, we will also examine the effect of stearic acid treatment fed exclusively to the db/+ dams on the extent of diabetes in the offspring. Finally, we will thoroughly examine the mechanism of action of stearic acid on fatty acid biochemistry in insulin resistant 3T3-L1 adipocytes. This aim is important because we will mechanistically evaluate a potential palliative intervention for both GDM and the accompanying diabetes of the offspring. 2. To determine the duration which stearic acid improves the diabetic phenotype in db/db mice. Db/db progeny will be treated with stearic acid and the duration and extent of the protective effect investigated. The effect of withdrawal of stearic acid on the lasting benefit of the intervention will also be examined. We will measure blood pressure, vascular responsiveness, weight and glucose. We will examine the mechanisms of stearic acid action by determining the expression and subcellular location of CD36, ABCD2, and mitoNEET in adipose and assessing function of each protein through measurements of adipose fatty acid biochemistry. This aim is important because it will provide data on the cardiovascular benefit and sustainability of stearic acid intervention. 3. To determine whether the beneficial effects of stearic acid are mediated by CD36, ABCD2, and/or mitoNEET. We will cross mice null for CD36, ABCD2, or mitoNEET with db/+ mice and assess the efficacious effects of stearic acid in ameliorating GDM and the ensuing diabetic phenotype of the double crossed db/db progeny lacking each individual gene. We will measure OGTT, vascular responsiveness, and adipose fatty acid biochemistry in db/+ dams. Furthermore, we will assess the effect of individual gene knockout on the ability of stearic acid to affect the development of diabetes in the db/db mice. This will be accomplished through measurements of weight, glucose, insulin, blood pressure, and vascular responsiveness. Mechanistically, the effects of gene ablation will be dissected through comprehensive analyses of isolated primary adipose biochemistry. This aim is critical because each double crossed mouse line will provide the definitive mechanistic data regarding the role of each protein in mediating the beneficial effects of stearic acid.