許立松Li-Sung Hsu黃敬恩Jing-En生化暨生物科技研究所2026-10-289999-12-312011https://handle.ncl.edu.tw/11296/6auw7yhttps://scholars.csmu.edu.tw/handle/123456789/35718紫草素( Shikonin)是從中國傳統中草藥材紫草屬所萃取出來，為一種天然的萘醌類；早期研究發現shikonin 具有抗菌、抗發炎、抗腫瘤與抗人類免疫缺陷病毒 (anti-HIV)的特性，但紫草素對於人類胃癌細胞的作用尚未被報導。本研究探討紫草素對人類胃腺癌細胞株AGS之抗癌效果，首先以MTT測試紫草素對AGS細胞毒殺效果，結果顯示隨濃度 (0.25-4μM)與處理時間 (6-24hr)增加下，有明顯抑制胃腺癌細胞生長現象，其半致死率在6小時為2μM在24小時則為1μM。使用propidium iodide (PI)與AnnexinⅤ利用流式細胞儀與tunel assay觀察，發現處理紫草素6小時細胞呈現壞死，相對而言，處理紫草素24小時細胞同時呈現凋亡與壞死現象，利用JC-1測其粒線體膜電位，可清楚看到無論是處理紫草素6或24小時，膜電位均有下降趨勢；蛋白質表現方面，在24小時隨著紫草素濃度增加下，pro-Caspase3表現下降，PARP蛋白被切割；p-Akt、p-Erk減少，p-p38上升，使用N-acetylcystenin (NAC)前處理24小時組別中，發現無論是MTT、粒線體膜電位、蛋白表現量均有恢復的情況。而在6小時組別我們使用Necrostatin-1 (Nec-1)前處理細胞，發現可降低紫草素對AGS毒殺效果；綜合以上的結果顯示紫草素可能成為一種治療胃腺癌的抗癌藥物。Shikonin is a major component of zicao (dried root of Lithospermum erythrorhizon) medicine with various biological activity, has been reported to possess significant antimicrobial, anti-inflammatoryand antitumor, anti-HIV effects. However, Shikonin of gastric adenocarcinoma mechanisms are not yet clearly understood. In this study, we was investigated the effect of shikonin on human adenocarcinoma gastric cells (AGS) molecular mechanisms. Shikonin significantly reduced cell viability in a dose (0.25-4μM) - and treatment time (6-24h)-dependent manner, as measured by MTT assay. The IC50 at 6 h and 24 h for AGS cells were 2 and 1μM, respectively. Tunel assay and Flow cytometric analysis of shikonin-treated AGS cells showed that the ratio of the apoptotic DNA fragmentation increased in 24h was a treatment dose dependent manner, but in 6h was not increased. We also used AnnexinⅤ/ propidium iodide (PI) assay by Flow cytometry. More importantly, it is clear to see decline in mitochondrial membrane potential (MMP), rapid generation of reactive oxygen species (ROS),decreased extracellular signal-regulated kinase (p38, Erk1/2 and Akt) phosphorylation、and was by accompanied cleavage poly (ADP-ribose) polymerase(PARP).Pretreatment with the antioxidant agent N-acetylcystenin (NAC) not only return to the phenomenon of shikonin induced ROS generation and MMP but also rescued PARP, pro-caspase3 and recover Erk1/2, Akt, p38 phosphorylation. In addition, Necrostatin-1 (Nec-1) duplicate shikonin -induced necroptosis event by MTT assay. Our results indicate that shikonin exerts potent anti- proliferative and apoptosis-inducing effects on human gastric adenocarcinoma cells.thesis