| 摘要: | 肥胖症是世界上常見的疾病，它增加了許多和代謝症候群相關疾病的風險，例如糖尿病，高血壓和心血管疾病。肥胖症的特徵是增加脂肪細胞的大小與數量，即分化與有絲分裂。由於白色脂肪細胞儲存過多能量，有利於肥胖的發展，而米色和棕色脂肪細胞消耗能量產生熱能，這有利於對抗肥胖，本篇論文的目的是研究來自檳榔或綠茶或丹蔘的天然和合成化合物對脂肪細胞分化的影響。使用3T3-L1白色脂肪細胞，我們發現檳榔鹼Arecoline，但不是Arecaidine或Guvacine，在12天分化期間處理100 μM抑制前脂肪細胞分化成脂肪細胞，從三酸甘油脂的累積減少所示。這表明檳榔對白色脂肪細胞的脂肪生成有生物鹼特異性作用。使用X9、D12和D16米色脂肪細胞，我們發現50 μM的綠茶表沒食子兒茶素沒食子酸酯（EGCG）傾向於減少8天分化過程中的細胞數和三酸甘油脂積累，而D12細胞對EGCG的反應比其他兩種米色脂肪細胞類型更敏感。這表明EGCG對米色脂肪細胞有細胞類型依賴性作用。使用HIB1B棕色脂肪細胞，我們發現EGCG、表兒茶素沒食子酸酯（ECG）、表沒食子兒茶素（EGC）和沒食子酸（Gallic acid），而不是表兒茶素（EC），可以在分化8天期間減少細胞數量和三酸甘油脂的積累，並且EGCG比其他綠茶兒茶素更有效。這表明兒茶素的特異性作用。此外，天然丹蔘二萜，如二氫丹蔘酮I（Dihydrotanshinone I，DHT-I），隱丹蔘酮（Cryptotanshinone）和丹蔘酮IIA（Tanshinone IIA），在HIB1B細胞分化過程中劑量依賴性的抑制細胞數和三酸甘油脂積累，而DHT-I比其他兩種化合物更有效。這表明丹蔘二萜的類型依賴性作用。合成的丹蔘化合物，例如化合物4、5和6，它們在處理10和50 μM後會抑制三酸甘油脂積累，並且前兩種化合物比最後一種化合物更有效。而根據濃度，在HIB1B棕色脂肪細胞中發現化合物4、5和6，改變脂肪細胞分化標記基因：脂肪細胞蛋白-2（adipocyte protein-2）、脂聯素（adiponectin）、PR domain containing (PRDM)-16、抵抗素（resistin）和解偶聯蛋白-1（uncoupling protein-1）的表達。總之，這些數據表明草藥化合物對脂肪細胞分化的影響隨處理劑量、天然和合成化合物的化學結構、脂肪形成基因和使用脂肪細胞系的類型而改變，並且提供兒茶素、檳榔生物鹼和丹蔘二萜類化合物用於預防和治療脂肪細胞相關疾病的可能性。;Obesity is a common disease in the world and increases the risk of many metabolic syndrome related diseases, such as diabetes, hypertension, and cardiovascular disease. It is characterized by increased sizes and numbers of adipocytes so-called differentiation and mitogenesis. As white adipocytes store too much energy, which favors development of obesity, and beige and brown adipocytes consume energy to produce heat, which favors anti-obesity, the overall objective of this thesis was designed to investigate the effects of natural and synthetic compounds derived from betel nuts, green tea, or danshen on adipogenic differentiation of fat cells. Using 3T3-L1 white fat cells, we discovered that betel nut arecoline, but not arecaidine or quvacine, inhibited the 12-day differentiation of preadipocytes into adipocytes after 100 μM of treatment, as indicated by reduced triglyceride accumulation. This suggests the alkaloid-specific effect of betel nut on white fat cell adipogenesis. Using X9, D12, and D16 beige fat cells, we discovered that green tea epigallocatechin-3-gallate (EGCG) at 50 μM tended to reduce the number of cells and triglyceride accumulation during the 8-day differentiation and that D12 cells were more sensitive to respond to EGCG than other two fat cell types. This suggests beige cell type-dependent effect of EGCG. Using HIB1B brown fat cells, we discovered that EGCG, epicatechin gallate, epigallocatechin, gallic acid, but not epicatechin, could reduce the number of cells and triglyceride accumulation during the 8-day period of differentiation and that EGCG was more effective than other tea catechins. This indicates the catechin-specific effect. In addition, native danshen diterpenoids, such as dihydrotanshinone I (DHT-I), cryptotanshinone, and tanshinone IIA, were found to dose-dependently inhibit cell number and triglyceride accumulation during HIB1B cell differentiation and DHT-I was more effective than other two compounds. This indicates diterpenoid type-dependent effect of danshen. When synthetic danshen compounds, such as compounds 4, 5, and 6, were examined, they could inhibit triglyceride accumulation after 10 and 50 μM of treatment and the former two compounds were more effective than the last one compound. Moreover, depending on the concentrations, compounds 4, 5, and 6 were found in HIB1B brown fat cells to differentially alter the expressions of adipogenic differentiation marker genes, adipocyte protein (aP)-2, adiponectin, PR domain containing (PRDM)-16, resistin, and uncoupling protein (Ucp)-1. Taken together, these data suggest that the effect of the herbal compounds on the differentiation of fat cells varies with doses of treatment, chemical structures of native and synthetic compounds, adipogenic genes, and types of fat cell lines used, as well as may provide possible uses of tea catechin, betel nut alkaloid, and danshen diterpenoid for prevention and cure of fat cell-related diseases. |
