鄭鈞文Chung-Wen Cheng吳靜怡生化暨生物科技研究所2026-10-289999-12-312007https://handle.ncl.edu.tw/11296/9b73mkhttps://scholars.csmu.edu.tw/handle/123456789/35418Diosgenin萃取於植物山藥的根是類固醇皂元 (steroidal sapogenin) 的一種，它已被報導具有不同的生物活性，包括:降血醣、合成類固醇荷爾蒙、抗氧化及抗發炎等效應。本篇研究，我們探討 diosgenin 對神經幹細胞分化之影響。從 14 天大白鼠的胚胎中獲得神經幹細胞以神經球方式 (neurospheres) 繁殖，在有或沒有處理 diosgenin 2 µM 不同情況下培養五天，與控制組相比， diosgenin 會明顯增加 microtubulin associated protein 2 (MAP2) 的比例。另外，結果顯示 diosgenin 會促進神經幹細胞分化成具有類神經纖維生長 (neurite outgrowth)、表現神經特定蛋白 Tuj1 及電感性鈣離子通道為特色的神經型態，更進一步， diosgenin 會誘導 ERK1/2 磷酸化的增加。若加入 U0126，其是選擇性 ERK1/2 kinase的抑制劑，會阻斷 ERK1/2 的磷酸化及 diosgenin 促進神經幹細胞分化成神經元的能力。 Diosgenin 結構相似於雌激素，本研究為了瞭解 diosgenin 誘導神經分化的過程中雌激素受體所扮演的角色，我們使用具高度專一性雌激素受體抑制劑 ICI182,780 阻斷雌激素受體相關路徑，結果發現ICI182,780並不能阻斷diosgenin 誘導神經分化。此結果指出 diosgenin 在誘導神經分化上不需要雌激素受體活化作用。綜合我們的實驗結果說明了diosgenin 誘導神經幹細胞分化是不需依賴雌激素受體路徑下，透過 ERK1/2 的活化所造成的。未來研究將更進一步探討 diosgenin 誘發神經幹細胞分化的詳細機轉。Diosgenin, a steroidal sapogenin is extracted from the root of wild yam (Dioscorea villosa). It has been reported to have various biological activites, including reducing blood sugar, synthesizing steroid hormone, antioxidant and anti-inflammatory effects. In this study, we examined the effect of diosgenin on neuronal differentiation of neural stem cells (NSCs). NSCs obtained from 14-day-old rat embryos were propagated as neurospheres and culture under differential conditions with or without diosgenin (2µM) for 5 days. Diosgenin significantly increased the percentage of microtubulin associated protein 2 (MAP2) in positive neurons compard with the control cells. In addition, these results show that diosgenin promote the differentiation of NSCs into a neuronal phenotype characterized by neurite outgrowth, the expression of neuronal marker protein Tuj1 and voltage-operated Ca2+ channel. Furthermore, diosgenin induced an increase in the phosphorylation of the extracellar signal regulated kinase 1/2 (ERK1/2). U0126, a selective ERK1/2 kinase inhibitor blocked both the phosphorylation of ERK1/2 and the ability of diosgenin to promote differentiation of NSCs into neuron. The structure of diosgenin is similar to that of estrogen. To investigate the possible role of the estrogen receptor (ER) in the course of a diosgenin-induced neurogenic effect, we used the highly specific ER antagonist ICI182,780 to blocked ER-related pathway. The addition of ICI182,780 did not alter diosgenin-induce neural differentiation. This data indicated that diosgenin does not require ER activation in neural differentiation. Taken together, our results suggest that diosgenin can induced NSCs differentiation through ERK1/2 activation in a ER-independent pathway. Future studies should evaluate the detailed mechanism during diosgenin-induced neural differentiation.thesis