胞內鈣離子變化在蘆薈大黃素導致小鼠胚胎凋亡所扮演的角色和調控機制

Roles and regulatory mechanisms of cytosolic calcium change in aloe-emodin-induced apoptosis in mouse embryos

陳子亮(Tzu-Liang Chen)

指導教授 ： 詹文雄

中原大學/工學院/生物科技研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200421

摘要

蘆薈大黃素是一種富含於蘆薈和大黄中的蒽醌類化合物，在中醫已被廣泛使用。一些研究證明蘆薈大黃素被當作一種抗氧化劑，抗發炎，抗癌藥物。近年來隨著越來越多的相關研究發現，蘆薈大黃素會抑制癌症細胞細胞週期的進行以及造成凋亡的現象，因此被廣為討論。由先前的研究結果已經證實處理蘆薈大黃素 (25 µM) 以上就會引起小鼠囊胚凋亡，亦會影響早期胚胎的發育，也使得胚胎內鈣離子濃度變化有所增加。但尚不清楚鈣離子在蘆薈大黃素導致胚胎凋亡的角色。因此，本研究的目的是探討鈣離子對於蘆薈大黃素誘導小鼠胚胎的細胞凋亡中之調控機制。之後更進一步的發現到胚胎內鈣離子隨著處理蘆薈大黃素濃度的升高而有所增加，而且經過蘆薈大黃素處理後，會增加胚胎內一氧化氮 (NO) 的生成。從實驗結果發現，鈣離子主要是透過胞器的釋放而不是以細胞膜上的鈣離子通道為主。此外，我們使用50 μM BAPTA-AM鈣離子螯合劑處理30分鐘去抑制胞內鈣離子濃度的變化，與蘆薈大黃素共培養12小時後，經由胚胎凋亡分析發現小鼠囊胚細胞凋亡數量有顯著的減少。綜合以上結果，我們推論蘆薈大黃素通過鈣離子依賴性途徑誘導細胞凋亡。

關鍵字

鈣離子 ； 蘆薈大黃素 ； 凋亡 ； 小鼠胚胎

並列摘要

Aloe-emodin (AE) is one of anthraquinone derivatives extracted from aloe leaves. It has been widely used in traditional Chinese medicines, such as laxatives, detoxifying agent, and beauty care product. Several studies demonstrated AE as an anti-oxidant, anti-inflammation, and anti-cancer agent. Conversely, it has been reported that AE could trigger cell apoptosis in mouse blastocyst. Previous study showed that apoptosis and a cytosolic calcium change could be induced by at least 25 μM AE in mouse blastocyst. Thus, the objective of this study is to investigate the regulatory mechanism of calcium change and Nitric oxide (NO) generation in Aloe-emodin-induced apoptosis and developmental injury in mouse embryos. The result showed that the major calcium change through the organelle but not the plasma membrane calcium channels. Furthermore, we used BAPTA-AM, known as intracellular calcium chelator, to inhibit calcium oscillation. Using TUNEL assay, we found that 30 minutes 50 μM BAPTA-AM pretreatment prior to 12 hours AE treatment can reduce significantly apoptotic cell number in mouse blastocyst. In conclusion, we suggest that Aloe-emodin-induced apoptosis through a calcium-dependent pathway.

並列關鍵字

calcium ； aloe-emodin ； apoptosis ； mouse embryo

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