第二型糖尿病是屬於一種胰島素抵抗的代謝異常。活性氧類會抑制胰島素調控的回應，且導致胰島素抵抗。第十型葡萄糖轉運子為從SLC2A10 gene 轉譯的蛋白質，其為促進葡萄糖轉運蛋白家族第三類的成員。在本實驗室，先前研究發現第十型葡萄糖轉運子在脂肪細胞中，第十型葡萄糖轉運子經過胰島素刺激，會位於粒腺體，而無胰島素刺激則位於高基氏體。
在脂肪細胞中，第十型葡萄糖轉運子被證實做為粒腺體的脫氫抗壞血酸(DHA)的轉運子。脫氫抗壞血酸為抗壞血酸的氧化態。而抗壞血酸為俗稱的維他命C，可以抵抗氧化壓力和誘使活性氧類下降。因此當第十型葡萄糖轉運子經過胰島素刺激，移動到粒腺體，可減少粒腺體內的活性氧類。胰島素抵抗是一種細胞無法回應胰島素的症狀。先前研究已知，提高活性氧類的程度可以抑制胰島素訊息傳遞路徑和葡萄糖攝取。
因此我們將比較第十型葡萄糖轉運子在脂肪細胞中，有關於胰島素訊息傳遞路徑、葡萄糖攝取、以及活性氧清除者的所扮演的角色。

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by insulin resistance. Reactive oxygen species (ROS) can suppress the insulin response and contribute to insulin resistance in adipocyte. Glucose transporter 10 (GLUT10) encoded by the SLC2A10 gene is a member of the class III facilitative glucose transporter family.
In our lab, we found GLUT10 was localized in the mitochondria after insulin-stimulated in adipocyte. In the unstimulated adipocyte, GLUT10 was localized in the Golgi apparatus. GLUT10 is confirmed as a DHA transporter in mitochondria in aortic smooth muscle cell (A10) and insulin-stimulated adipocytes (3T3-L1). DHA is the oxidized form of ascorbic acid. Ascorbic acid (also called vitamin C) can against oxidative stress and induce to decreasing of ROS level in cell. When the GLUT10 targeted to mitochondria by insulin-stimulated, it can reduce ROS level. The cells fail to respond to insulin in insulin resistance. Previous studies have shown that elevated ROS level in mitochondria can inhibit insulin signal pathway and glucose uptake. Therefore, we will understand the role of GLUT10 in insulin signal pathway, glucose uptake and ROS scavenger in adipocyte.

中文摘要
Abstract
誌謝辭
List of contents
Abbreviations
I. Introduction
1. Type 2 diabetes mellitus associated with Glucose transporter 10 ……...P.1
2. The DHA transport role of GLUT10 in mitochondria is associated with oxidative stress in muscle cells and adipocytes …………………………..P.2
3. Specific aims ……………………………………………………………...P.4
II. Materials and methods
1. Cell Culture ……………………………………………………….….…...P.5
2. Adipogenesis ………………………………...……………….……..…… P.5
3. Oil-Red-O Staining ……...………………...……………….……………P.6
4. Transfection ………………………………………………………….…...P.7
5. Induction of Oxidative Stress and Insulin Stimulation by high glucose treatment ………………………………………………………….…........P.8
6. Primer Design …………………………………………………….…........P.9
7. Isolation of RNA ……………………………………………….…............P.9
8. Reverse transcription amplification reaction (RT-PCR) ……….…..........P.11
9. Real-time polymerase chain reaction (real time PCR) ...…….….............P.11
10. Statistical analysis ………………………………………………..........P.12
III. Result
1. Determine the role of GLUT10 in adipocytes under conditions of high glucose The differentiation of adipocytes….…………….…....................P.13
1.1 Expression of three antioxidant genes under high glucose condition
1.2 The gene expression of JNK-1 is reduced upon insulin stimulation
1.3 The transcription levels of genes involved in the insulin signal-transduction pathway under high glucose conditions in adipocytes
1.4 GLUT4 transcription level was not affected by translocation of GLUT10 to mitochondria during prolonged oxidative stress
2. Comparison of gene expression patterns between control and GLUT10 over-expressing adipocytes ………………………………………..…….P.18
2.1 Gene expression of catalase, SOD-1, and SOD-2 in GLUT10 over-expressing adipocytes
2.2 The gene expression of JNK-1 in GLUT10 over-expressing adipocytes
2.3 The transcription level of GLUT4 and of genes involved in the insulin-signaling pathway in GLUT10 over-expressing adipocytes
3. GLUT10 gene expression decreases following insulin stimulation …….P.21
Ⅳ. Discussion
1. Mitochondrial GLUT10 modulates antioxidants and JNK-1 under oxidative stress conditions ………………………………………………………...P.22
2. GLUT10 mitochondrial function affects GLUT4 and molecules involved in the insulin-signaling pathway under oxidative stress conditions …...…..P.24
3. GLUT10 over-expression modulates the gene expression of anti-oxidant molecules and molecules of the insulin-signaling pathway in adipocytes ……………………………………………………………….P.26
4. The regulation of GLUT10 expression in the presence of insulin or high glucose …………………………………………….…………...…......P.29
Reference …………………………………………….………………………….....P.30
Table …………………………………………….…………………………............P.35
Figures ………………………………………….…….……………………............P.37

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