title: Role of mitochondrial permeability transition in human hepatocellular carcinoma Hep-G2 cell death induced by rhein.
abstract: Rhein, a compound found as a glucoside in the root of rhubarb, is currently a subject of interest for its antitumor properties. The apoptosis of tumor cell lines induced by rhein was observed, and the involvement of mitochondria was established; however, the role of mitochondrial permeability transition (MPT) remains unknown. Here we report that MPT plays an important role in the apoptosis of human hepatocellular carcinoma Hep-G2 cells induced by rhein. After adding rhein to the isolated hepatic mitochondria, swelling effects and the leakage of Ca(2+) were observed. These alterations were suppressed by cyclosporin A (CsA), an MPT inhibitor. Furthermore, in Hep-G2 cells, the decrease of ATP production, the loss of mitochondrial transmembrane potential (MTP), the release of cytochrome c (Cyto c), and the activation of caspase 3 were also observed. These toxic effects of rhein can also be attenuated by CsA as well. Moreover, TUNEL assay confirmed that in the presence of CsA, rhein-induced apoptosis was largely inhibited. These results suggest that MPT plays a critical role in the pathogenesis of Hep-G2 cell injury induced by rhein, and imply that MPT may contribute to the anti-cancer activity of rhein.
authors.affiliation: Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Du
authors.affiliation: Department of Pharmacy, Luwan Branch of Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Pharmacy, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Xiao-Lan
authors.initials: XL
authors.lastname: Bian
authors.affiliation: Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
authors.forename: Xiao-Le
authors.initials: XL
authors.lastname: Xu
authors.affiliation: Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhu
authors.affiliation: Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China. Electronic address: miguelboyu@msn.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.affiliation: Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China. Electronic address: zhaiqing63@hotmail.com.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhai
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000880:Anthraquinones / Q000494:pharmacology* / Q000627:therapeutic use; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D016572:Cyclosporine / Q000494:pharmacology; D045304:Cytochromes c / Q000378:metabolism; D056945:Hep G2 Cells; D006801:Humans; D020287:In Situ Nick-End Labeling; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects*; D010539:Permeability / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D012250:Rheum / Q000737:chemistry*
chemical_list: D000880:Anthraquinones; D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D016572:Cyclosporine; D000255:Adenosine Triphosphate; D045304:Cytochromes c; D053148:Caspase 3; C020491:rhein
keywords: 2-[4-(2-Hydroxyethyl)-1-piperazine] ethanesulfonic acid; 6-Diamidino-2-phenylindole; Cell death; CsA; Cyclosporine A; Cyto c; Cytochrome c; DAPI 4′; FITC; Fluorescein isothiocyanate; GAPDH; Glyceraldehyde-3-phosphate dehydrogenase; HEPES; HRP; Hep-G2; Horseradish peroxidase; MPT; MTP; Mitochondrial permeability transition; Mitochondrial transmembrane potential; PBS; Phosphate-buffered saline; ROS; Reactive oxygen species; Rhein; SDS–PAGE; Sodium dodecyl sulfate–polyacrylamide gel electrophoresis; TBS; Tris-buffered saline