台灣鄉土蔬菜 - 紅甘藷葉粗萃物對人類結直腸癌細胞之影響

Effect of crude extract from purple sweet potato leaves on human colorectal carcinoma cell

黃美子(Mei-Tzu Huang)

指導教授 ： 劉珍芳

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(2006年)

摘要

本研究以台灣地區鄉土蔬菜中多酚類含量較高之紅甘藷葉（purple sweet potato leaves, PSPL）進行探討，以瞭解其對結直腸癌是否具有影響。實驗設計係以細胞模式進行，選用人類結直腸癌細胞株（HT-29）作為實驗材料，給予HT-29細胞株不同濃度之紅甘藷葉粗萃物，在不同時間作用下，觀察其對HT-29細胞增生、分化及細胞凋亡（apoptosis）的影響。研究結果顯示，濃度為0.2、0.3、0.4、0.5、0.6及0.8 mg/mL之紅甘藷葉粗萃物，添加於細胞中48及72小時後，可明顯抑制HT-29細胞之生存率（p＜0.05）。在細胞分化部份，則有隨著濃度增加而增加細胞分化之趨勢。當以流式細胞儀分析細胞週期變化之結果顯示，於細胞中添加濃度為0.15、0.3及0.6 mg/mL之紅甘藷葉粗萃物48小時後，可增加sub G0 階段的細胞數量百分比（p＜0.05）。而以TUNEL螢光染色法分析細胞內DNA裂片（DNA fragmentation）時之結果顯示，濃度0.3 mg/mL及0.6 mg/mL之紅甘藷葉粗萃物可顯著增加DNA fragmentation之比例，代表具有誘發細胞凋亡之現象。以Annexin-V/PI 螢光染劑偵測細胞凋亡與細胞壞死之結果顯示，於細胞中添加濃度為0.3及0.6 mg/mL之紅甘藷葉粗萃物36小時後，確實可誘發細胞發生apoptosis，但於0.6 mg/mL濃度則同時會增加細胞necrosis。綜合以上結果得知，紅甘藷葉粗萃物對於人類結直腸癌細胞株（HT-29），具有抑制細胞生長及誘導細胞凋亡之現象產生。

關鍵字

紅甘藷葉 ； 多酚類物質 ； 結直腸癌細胞 ； 細胞凋亡

並列摘要

The aim of this study was to investigate the effects of crude extracts from indigenous vegetable - purple sweet potato leaf (PSPL) on the proliferation, differentiation and apoptosis of human colorectal carcinoma cell (HT-29 cell) The results obtained from MTS assay showed that PSPL crude extract (0.2, 0.3, 0.4, 0.5, 0.6 & 0.8 mg/mL) could inhibit HT-29 cell proliferation (p＜0.05）, but did not increase cell differentiation conspicuously. In addition, the flow cytometric analysis showed that after 48 hr treated with PSPL crude extract (0.15, 0.3 & 0.6 mg/mL) could increase sub G0 phase (apoptotic cells) cell numbers (p＜0.05）. The test of Annexin-Ⅴ/PI fluorescence showed that PSPL crude extract (0.3 & 0.6 mg/mL) could significantly induce the cell apoptosis after 36 hr treatment, but in high dose (0.6 mg/mL) of PSPL crude extract also could induce cell necrosis. In conclusion, the PSPL crude extract from indigenous vegetable -- purple sweet potato leaf would suppress colorectal carcinoma cell growth by induction of apoptosis, but in higher dose may also induce cell necrosis to mediate the growth inhibition.

並列關鍵字

purple sweet potato leaf ； polyphenol ； colorectal cancer ； apoptosis

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