2018-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/651657摘要：糖尿病盛行全球，導致各種併發症，也是主要死因之一。進一步了解糖尿病的致病機轉，進而發展治療糖尿病的方法，將有助於人類的健康。Vascular adhesion protein-1 (VAP-1，不是vascular cellular adhesion molecule，也不是VCAM-1)是個發炎因子並具有酵素活性。我們先前的研究發現，人類血中VAP-1濃度可預測糖尿病併發症的發生。在動物模式中，我們發現抑制VAP-1可減少氧化壓力與發炎反應，進而預防與治療動脈硬化。在此實驗中我們意外發現，抑制VAP-1也可以降低血糖。然而，此結果與文獻中短期抑制VAP-1的結果不同。由於兩篇論文使用的抑制劑與時間不同、動物模式也不同，因此，我們將在本計畫中，利用VAP-1剔除小鼠，以糖尿病的動物模式來探討VAP-1在血糖調節的真正角色。此外，我們發現小鼠腸子VAP-1的表現量高，可能會影響腸內菌相、胃腸道荷爾蒙分泌、膽汁代謝與metabolic endotoxemia，進而透過脂肪組織上VAP-1的作用，影響脂肪組織發炎以及脂肪激素(adipokines)的分泌，導致血糖的變化。因此，本計畫將以diet-induced obesity model，比較wild-type與VAP-1剔除小鼠，在intraperitoneal glucose tolerance test、insulin tolerance test與hyperglycemic clamp等實驗的結果，並分析腸道菌叢，測定血中內毒素、胃腸道荷爾蒙與脂肪激素濃度，也將分析脂肪組織發炎與抗發炎指標，腸道與肝臟FXR的表現、腸道TGR5的表現、以及肝臟、脂肪組織與骨骼肌中與胰島素作用相關的蛋白表現。我們也將以streptozotocin-induced diabetes model，比較wild type與VAP-1剔除小鼠，血糖與胰島素敏感性是否有差異。此外，我們也將連續輸注內毒素來模擬metabolic endotoxemia，並比較wild-type與VAP-1剔除小鼠，脂肪組織發炎以及胰島素敏感性的差異。同時我們也將於細胞模式中，探討VAP-1對於提取葡萄糖的詳細機轉。此外，利用之前收錄的人類世代，我們也將探討人類血中VAP-1濃度，與肥胖指標、內臟與皮下脂肪的面積、胰島素敏感性、血糖、發炎指標與脂肪激素的關係。<br> Abstract: Diabetes is a prevalent disease all over the world, which results in various complications and is a major cause of death. Vascular adhesion protein-1 (VAP-1, NOT vascular cellular adhesion molecule, NOT VCAM-1) participates in inflammation and has an enzymatic activity. We have reported that plasma VAP-1 can predict the incidence of diabetic complications. In animal model, we found that inhibition of VAP-1 can reduce oxidative stress, inflammation and atherosclerosis. To our surprise, we found that inhibition of VAP-1 can also decrease plasma glucose. However, this finding is different from another report. Since these two studies used different inhibitors with different treatment durations in different animal models, we will use VAP-1 knockout mice in diabetes animal model to investigate the role of VAP-1 in glucose metabolism. In wild-type mice, we found a high VAP-1 expression in intestines. We hypothesize that intestinal VAP-1 may influence gut microbiome, secretion of gut hormones and incretins, bile acid metabolism and metabolic endotoxemia, which may affect adipose tissue inflammation and secretion of adipokines through VAP-1 in adipose tissue. All these mechanisms may result in an alteration of glucose metabolism. In this project, we will use diet-induced obesity model to compare the results of intraperitoneal glucose tolerance test, insulin tolerance test and hyperglycemic clamp in wild-type and VAP-1 knockout mice. We will measure their gut microbiome, plasma concentrations of lipopolysaccharide, peptide YY, incretins and adipokines. We will measure pro-inflammatory and anti-inflammatory markers in adipose tissue, FXR expression in intestine and liver, TGR4 expression in intestine, and insulin signaling proteins in liver, adipose tissue and skeletal muscles. We will use streptozotocin-induced diabetes model to compare plasma glucose and insulin sensitivity in wild-type and VAP-1 knockout mice. Besides, we will infuse lipopolysacchride continuously as a model for metabolic endotoxemia, and compare adipose inflammation and insulin sensitivity in this model in wild-type and VAP-1 knockout mice. We will investigate the mechanisms of VAP-1 on glucose uptake in hepatic and adipose cell models. Besides, we will use data and samples from a human cohort to explore the relationship between plasma VAP-1 concentrations, obesity measures, visceral and subcutaneous abdominal fat areas, insulin sensitivity, and plasma concentrations of glucose, inflammatory markers and adipokines.血管附著蛋白1糖尿病腸內菌相脂肪組織發炎Vascular adhesion protein-1diabetesgut microbiomeadipose inflammation