請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/63741
標題: | 硫化氫在剪力誘發內皮細胞訊息傳遞中之角色探討 The Role of Hydrogen Sulfide in Shear-induced Signal Transduction in Endothelial Cells |
作者: | Chia-Yu Hsiao 蕭嘉瑜 |
指導教授: | 謝學真(Hsyue-Jen Hsieh) |
關鍵字: | 剪力,硫化氫,內皮細胞,訊息傳遞,心血管保護,Akt,eNOS, shear stress,hydrogen sulfide,endothelial cells,signal transduction,cardioprotective,Akt,eNOS, |
出版年 : | 2012 |
學位: | 碩士 |
摘要: | 硫化氫 (hydrogen sulfide, H2S) 為近年來繼一氧化氮 (nitric oxide, NO) 與一氧化碳 (carbon monoxide) 發現的第三個氣體訊息傳遞分子 (gasotransmitter),其對心血管系統 (cardiovascular system) 有諸多保護作用。層流剪力 (laminar shear stress) 亦已被證實對心血管系統有保護作用,且其所引發的訊息傳遞與硫化氫所引發的訊息傳遞有類似之處,然而目前為止,硫化氫與剪力之間的關係尚未明朗。故本研究將探討剪力對體內硫化氫生成量的調控,以及硫化氫在剪力誘發訊息傳導中所扮演的角色。
在心血管系統中,剪力主要作用於血管內皮細胞 (vascular endothelial cell) 上,故本實驗以牛主動脈內皮細胞 (bovine aorta endothelial cell, BAECs) 與人類臍帶靜脈內皮細胞 (human umbilical vein endothelial cells , HUVECs) 為模式,觀察剪力刺激對硫化氫生成量變化的影響,並利用 siRNA 轉染技術 (transfection) 抑制與硫化氫生成有關的三種酵素,分別為:cystathionine-β-synthase (CBS)、cystathionine-γ-lyase (CSE) 及 3-mercapto-sulfurtransferase (3-MST),藉以探討硫化氫於剪力誘導訊息傳遞中所扮演的角色。實驗結果發現,在以剪力刺激 30 分鐘與 1 小時後,內皮細胞硫化氫的生成速率上升了約兩倍,顯示剪力可能透過增加硫化氫的生成對心血管系統產生保護作用。而在訊息傳導方面,以 CBS、CSE 與 3-MST siRNA 轉染抑制硫化氫生成的內皮細胞對剪力刺激之後所誘導的 Akt 磷酸化有抑制的情形,說明硫化氫的生成可能是細胞受到剪力之後 pAkt 上升的原因之一。而另一方面,eNOS 在剪力刺激後的磷酸化程度亦受到 CBS siRNA 與 CSE siRNA 的抑制,顯示硫化氫對 eNOS 可能有所交互作用。 綜合以上結果,本研究認為剪力可能透過增加硫化氫的產生進而對心血管系統產生保護作用,而在剪力誘導之訊息傳遞中,硫化氫亦扮演了重要的角色,並可能對 eNOS 有所影響。 Hydrogen sulfide (H2S) is a novel gasotransmitter in cardiovascular system and has been shown to exert various cardioprotective effects. Blood flow-induced laminar shear stress exerted on endothelial cells (ECs) is also essential for maintaining normal vasculature. Laminar shear stress applied to ECs triggers signaling mechanisms similar to those induced by H2S treatment. However, knowledge regarding the H2S production and its functional role in ECs under the influence of shear flow is not clear. In the present study, efforts were made to investigate the H2S production in ECs under shear flow and its potential role in shear-induced cell signaling. Human umbilical vein endothelial cells (HUVECs) and bovine aortic endothelial cells (BAECs) were subjected to shear stress in a well-defined parallel plate system. BAECs exposed to shear stress (12 dyn/cm2) for 30 minutes and 60 minutes increased the H2S production rate by 2-folds. To study the signaling role of H2S, ECs were treated with H2S donor (sodium sulfide). It was found that H2S treatment increased Akt activation in ECs. To further explore the role of H2S in shear-induced cellular responses, HUVECs with cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE) , 3-mercapto-sulfurtransferase (3-MST) knocked down by siRNAs were subjected to shear stress. Results showed that shear-induced Akt phosphorylation was attenuated in those ECs, indicating that H2S may play a role in shear-induced Akt signaling. Our findings strongly suggest that endogenous H2S levels in ECs can be enhanced by shear flow and this H2S production may contribute to the shear-induced signaling mechanisms such as Akt activation. Our results offer some insights into the physiological roles of H2S in regulating endothelial responses under shear stress. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/63741 |
全文授權: | 有償授權 |
顯示於系所單位: | 化學工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-101-1.pdf 目前未授權公開取用 | 3.49 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。