The mechanism of tagitinin D-induced apoptosis of HepG2 cells
(2.State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201)
【Abstract】Tagitinin D was identified as one of the main compounds present in plants of Asteraceae, which exhibited anti-tumor activities. To explore the mechanism of HepG2 cell apoptosis induced by tagitinin D, we used colony formation assay to detect the cell proliferation ability. Then, we determined the cell cycle and apoptosis by flow cytometry, the reactive oxygen species (ROS) level by DCFH-DA, and ER stress-related protein expression level by Western blot assay. The results showed that tagitinin D increased ROS levels, inhibited the cell proliferation, arrested the cell cycle in the G2/M phase, and induced apoptosis of HepG2 cells. The expression levels of proteins, such as PDI, Calnexin, Ero1-Lα, Bip, IRE1-Lα, and p-eIF2α, involved in ER stress signaling pathway were up-regulated. In summary, all the data suggested that tagitinin D induced ROS which further elicited the ER stress response and led to apoptosis of HepG2 cells.
【Keywords】 tagitinin D; ROS; apoptosis; ER stress signaling pathway;
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