Ketosis, Vascular Inflammation and Its Therapy in Type 1 Diabetic Patients

描述（由申请人提供）：本申请高度响应NIH的三个项目公告：PAR-06 - 457（糖尿病转化研究）、PA-01 - 114（铬作为糖尿病辅助治疗）和PA-01 - 071（医学中的金属）。1型糖尿病与心血管疾病（CVD）的过度发病率有关。促炎细胞因子白细胞介素（IL）-6和组织坏死因子（TNF）-α的血液水平升高是血管炎症的标志物，血管炎症是CVD的已知风险因素。除了高血糖症，1型糖尿病患者经常发生酮症。我们的初步研究表明，在使用U937单核细胞的细胞培养模型中，酮体乙酰乙酸酯（AA）可产生超氧自由基并增加IL-6和TNF-α的分泌;与正常酮血症的1型糖尿病患者相比，高酮血症的1型糖尿病患者血液中的氧化应激和IL-6和TNF-α水平更高;并且铬（Cr 3+）在细胞培养模型中抑制由AA引起的TNF-α和IL-6的分泌。这一提议有两个假设。首先，酮症增加了1型糖尿病患者血管炎症标志物的血液水平。第二，补充Cr3+可以预防/降低1型糖尿病患者血管炎症标志物的血液水平。这些假设将在1型糖尿病患者体内以及使用从受试者血液中分离的单核细胞和购买的人主动脉内皮细胞（HAEC）的体外研究中进行测试。在体内，将检查高酮血症和补充安慰剂（P）或Cr 3+对血管炎症标志物水平的影响。在体外，从补充P或Cr3+的患者或HAEC分离的单核细胞将与酮一起培养，以检查其对血管炎症标志物以及与单核细胞和HAEC中的细胞因子产生和粘附分子相关的基因表达的直接影响。这是一项新的研究，因为之前没有研究检查酮症或Cr3+对1型糖尿病血管炎症的影响。为了实现这些目标，将从1型糖尿病儿童中采集血液。患者（n = 141，年龄12 - 18岁）将补充P或200或500 μ g Cr 3 +-烟酸盐/天，持续3个月。将使用最先进的方法，如多重PCR。将对数据进行统计分析。糖尿病发病率已成为流行病，仍然是一个主要的公共卫生问题。长期目标是了解酮症在CVD中的作用，并发现一种相对低成本的膳食补充剂，可用作1型糖尿病CVD预防的辅助治疗。

DESCRIPTION (provided by applicant): This application is highly responsive to three program announcements of the NIH: PAR-06-457 (Translational Research in Diabetes), PA-01-114 (Chromium as Adjuvant Therapy in Diabetes), and PA-01- 071 (Metals in Medicine). Type-1 diabetes is associated with excessive incidence of cardiovascular disease (CVD). Elevated blood levels of the pro-inflammatory cytokines interleukin (IL)-6 and tissue necrosis factor (TNF)-a are markers of vascular inflammation, a known risk factor for CVD. In addition to hyperglycemia, type 1 diabetic patients frequently experience ketosis. Our preliminary studies have demonstrated that the ketone body acetoacetate (AA) can generate superoxide radicals and increase secretion of IL-6 and TNF-a in a cell culture model using U937 monocytes; that oxidative stress and levels of IL-6 and TNF-a are higher in the blood of hyperketonemic compared with normoketonemic type 1 diabetic patients; and that chromium (Cr3+) inhibits the secretion of TNF-a and IL-6 caused by AA in a cell culture model. This proposal has two hypotheses. The first is that ketosis increases blood levels of markers of vascular inflammation in type 1 diabetes. The second is that Cr3+ supplementation can prevent/lower blood levels of vascular inflammation markers in type 1 diabetes. These hypotheses will be tested both in vivo in type 1 diabetic patients as well as in vitro in studies using monocytes isolated from subject's blood and purchased human aortic endothelial cells (HAEC). In vivo, the effects of hyperketonemia, and supplementation with either placebo (P) or Cr3+ on the levels of markers of vascular inflammation will be examined. In vitro, monocytes isolated from P or Cr3+ supplemented patients or HAEC will be cultured with ketones to examine their direct effect on markers of vascular inflammation and gene expression related to cytokine production and adhesion molecules in monocytes and HAEC. This is a novel study because no prior study has examined the effect of ketosis or Cr3+ on vascular inflammation in type 1 diabetes. To accomplish these objectives, blood will be collected from type 1 diabetic children. Patients (n=141, ages 12- 18 yrs) will be supplemented with either P or 200 or 500¿g Cr3+-niacinate/day for 3 months. State of the art methodology, such as multiplex PCR, will be used. Data will be analyzed statistically. Diabetes incidence has become epidemic and remains a major public health issue. The long-term goal is to understand the role of ketosis in CVD and to discover a relatively low-cost dietary supplement that could be used as an adjuvant therapy for CVD prevention in type 1 diabetes.