title: Isoorientin from Gypsophila elegans induces apoptosis in liver cancer cells via mitochondrial-mediated pathway.
abstract: BACKGROUND
  Gypsophila elegans has been used as a traditional herbal medicine for treating immune disorders and chronic liver diseases in China. The aim of this study is to isolate an active ingredient from this herb and investigate its anti-tumor activity.
  
  
  METHODS
  An active ingredient was isolated from the ethanol extract using bioassay-guided screening. And its anti-tumor activity was analyzed by testing the cytotoxicity, lactate dehydrogenase (LDH) release, clonogenecity and migration in HepG2 cells. To investigate its potential mechanism, cell apoptosis, cell cycle arrest, reactive oxygen species (ROS), cytochrome c, mitochondria membrane potential (MMP) and caspase level were determined in liver cancer cell line HepG2.
  
  
  RESULTS
  A flavonoid glycoside, i.e., G. elegans isoorientin (GEI), was isolated from this herb and identified as Isoorientin-2″-O-α-l-arabinopyranosyl. Our results showed that GEI significantly inhibited the viability and proliferation of HepG2 cells in a dose- and time-dependent manner, and its cytotoxic effect was also confirmed by the elevated level of LDH. GEI treatment could markedly inhibit the clonogenicity and migration of HepG2 cells. Moreover, GEI induced remarkable apoptotic death of HepG2 cells through cell cycle arrest at G1 phase via the regulation of cell cycle-related genes, such as cyclin D, cyclin E and CDK2. Further study showed that GEI treatment significantly elevated ROS formation, followed by attenuation of MMP via up-regulation of Bax and down-regulation of Bcl-2, accompanied by cytochrome c release to the cytosol. In addition, GEI treatment resulted in a significant dose-dependent increase in caspase-3 and -9 proteolytic activities.
  
  
  CONCLUSIONS
  The present study demonstrates that the ability of GEI to induce apoptosis against HepG2 cells mediated by mitochondrial-mediated pathway.
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Lin
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Jinbin
authors.initials: J
authors.lastname: Wei
authors.affiliation: Guangxi Medical University, Nanning 530021, China; The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning 530023, China.
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Ping
authors.initials: P
authors.lastname: He
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Shimei
authors.initials: S
authors.lastname: Tan
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Jinlan
authors.initials: J
authors.lastname: Nie
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Shengjuan
authors.initials: S
authors.lastname: Lu
authors.affiliation: Guangxi Medical University, Nanning 530021, China.
authors.forename: Min
authors.initials: M
authors.lastname: He
authors.affiliation: The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning 530023, China; Department of Biochemistry, University of Arkansas Medical School, 4301 W. Markham, Little Rock, AR 72205-7199, USA.
authors.forename: Zhongpeng
authors.initials: Z
authors.lastname: Lu
authors.affiliation: The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning 530023, China. Electronic address: hqf00@126.com.
authors.forename: Quanfang
authors.initials: Q
authors.lastname: Huang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D029748:Caryophyllaceae; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D056741:Cyclin D / Q000235:genetics; D019927:Cyclin E / Q000235:genetics; D051357:Cyclin-Dependent Kinase 2 / Q000235:genetics; D056945:Hep G2 Cells; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D047311:Luteolin / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000502:physiology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics
chemical_list: D000970:Antineoplastic Agents; C494826:BAX protein, human; D056741:Cyclin D; D019927:Cyclin E; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C057912:homoorientin; D007770:L-Lactate Dehydrogenase; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; D020169:Caspases; D047311:Luteolin
keywords: Cytotoxicity; Gypsophila elegans; Isoorientin; Mitochondrial-mediated pathway; Reactive oxygen species