title: Crude extract of Rheum palmatum L induced cell death in LS1034 human colon cancer cells acts through the caspase-dependent and -independent pathways.
abstract: Crude extract of Rheum palmatum L (CERP) has been used to treat different diseases in the Chinese population for decades. In this study, we investigated the effects of CERP on LS1034 human colorectal cancer cells in vitro and also examined possible mechanisms of cell death. Flow cytometric assays were used to measure the percentage of viable cells, cell cycle distribution including the sub-G1 phase (apoptosis), the activities of caspase-8, -9, and -3, reactive oxygen species (ROS) and Ca(2+) levels, and mitochondrial membrane potential (ΔΨm). DNA damage, nuclei condensation, protein expression, and translocation were examined by Comet assay, 4'-6-diamidino-2-phenylindole (DAPI) staining, Western blotting, and confocal laser system microscope, respectively. CERP induced apoptosis as seen by DNA fragmentation and DAPI staining in a concentration- and time-dependent manner in cancer cells. CERP was associated with an increase in the Bax/Bcl-2 protein ratio and CERP promoted the activities of caspase-8, -9, and -3. Both ROS and Ca(2+) levels were increased by CERP but the compound decreased levels of ΔΨm in LS1034 cells. Laser confocal microscope also confirmed that CERP promoted the expressions of AIF, Endo G, cytochrome c, and GADD153 to induce apoptosis through mitochondrial-dependent pathway.
authors: Graduate Institute of Chinese Medicine, China Medical University, Taichung 404, Taiwan; Department of Chinese Medicine, Changhua Hospital, Department of Health, Executive Yuan, Changhua 513, Taiwan.
authors: Yi-Shih
authors: YS
authors: Ma
authors: Shu-Chun
authors: SC
authors: Hsu
authors: Shu-Wen
authors: SW
authors: Weng
authors: Chien-Chih
authors: CC
authors: Yu
authors: Jai-Sing
authors: JS
authors: Yang
authors: Kuang-Chi
authors: KC
authors: Lai
authors: Jing-Pin
authors: JP
authors: Lin
authors: Jaung-Geng
authors: JG
authors: Lin
authors: Jing-Gung
authors: JG
authors: Chung
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D020169:Caspases / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000201:enzymology / Q000473:pathology*; D020552:Comet Assay; D045304:Cytochromes c / Q000378:metabolism; D004249:DNA Damage; D006801:Humans; D007211:Indoles / Q000737:chemistry; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D021381:Protein Transport; D017382:Reactive Oxygen Species / Q000378:metabolism; D012250:Rheum / Q000737:chemistry*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D007211:Indoles; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C007293:DAPI; D045304:Cytochromes c; D020169:Caspases; D002118:Calcium
keywords: apoptosis; crude extract of Rheum palmatum L; human colon cancer LS1034 cells; mitochondrial