| 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。
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. |
