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 的三个计划公告：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) 的高发病率有关。促炎细胞因子白细胞介素 (IL)-6 和组织坏死因子 (TNF)-a 的血液水平升高是血管炎症的标志，血管炎症是 CVD 的已知危险因素。除了高血糖之外，1 型糖尿病患者还经常出现酮症。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（AA）可以产生超氧自由基并增加IL-6和TNF-a的分泌；与正常酮血症 1 型糖尿病患者相比，高酮血症患者血液中的氧化应激以及 IL-6 和 TNF-a 水平较高；在细胞培养模型中，铬 (Cr3) 可以抑制 AA 引起的 TNF-a 和 IL-6 的分泌。该提案有两个假设。首先，酮症会增加 1 型糖尿病血管炎症标志物的血液水平。其次，补充 Cr3 可以预防/降低 1 型糖尿病患者血液中血管炎症标志物的水平。这些假设将在 1 型糖尿病患者的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，将检查高酮血症以及补充安慰剂 (P) 或 Cr3 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 中分离出的单核细胞将与酮一起培养，以检查它们对血管炎症标志物以及与单核细胞和 HAEC 中细胞因子产生和粘附分子相关的基因表达的直接影响。这是一项新颖的研究，因为之前没有研究检验过酮症或 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 型糖尿病儿童身上采集血液。患者（n = 141，年龄 12-18 岁）将每天补充 P 或 200 或 500 克 Cr3 -烟酸，持续 3 个月。将使用最先进的方法，例如多重 PCR。将对数据进行统计分析。糖尿病发病率已成为流行病，并且仍然是一个重大的公共卫生问题。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 预防的辅助疗法。

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.