title: [Apoptosis of multiple myeloid cells induced by polysaccharides extracts from Hedyotis diffusa and its mechanism].
abstract: OBJECTIVE
  To explore the proliferation inhibition and apoptosis effects of polysaccharides extracts from Hedyotis diffusa (PEHD) on multiple myeloma (MM) cell line RPMI 8226 cells in vitro, so as to provide experimental theory for the clinical application in the treatment of MM.
  
  
  METHODS
  MTT assay was used to examine the effects of PEHD on cell growth. The apoptotic cells were analyzed by flow cytometry with AnnexinⅤ/PI staining. Hoechst staining was used to observe the morphological changes of RPMI 8226 cell apoptosis. The expression levels of caspase-3,-8,-9, PARP, nucleoprotein NF-κB protein and other channel protein were assayed by Western blotting method.
  
  
  RESULTS
  The growth of RPMI 8226 cells were suppressed after treatment with PEHD, the highest inhibition rate reached to 92.3%, the results in the doses from 1 to 4 mg/ml showed a dose-and-time-dependent manner. The proportion of apoptotic cells in 1, 2 and 3 mg/ml PEHD treatment groups for 24 h were 22.52%, 62.31% and 69.94%, respectively, and significantly higher than that of control 8.93%. After treated with PEHD, apoptotic body appeared in RPMI 8226 cells nucleus and the number of apoptotic body increased in a dose-dependent manner. With the increasing of PEHD concentration, the expression of caspase-8,-9,-3 and PARP protein increased. The expression of Mcl-1, Bcl-xl, Bid and Bim protein decreased gradually, but the expression of Bax, Bak and Bad protein increased, and the expression of p-AKT protein (60 kDa) and NF-κB obviously decreased.
  
  
  CONCLUSIONS
  PEHD could inhibited the growth of RPMI 8226 cells and displayed a dose-and-time-dependent manner, its mechanism may involve cell apoptosis induction, which was associated with the activation of caspase-8, caspase-9, and caspase-3 protein and the down-regulation of p-AKT and NF-κB protein expression.
authors.affiliation: Department of Hematology, the First Affiliated Hospital of Zhejiang University of Traditional Chinese Medicine, Hangzhou, China.
authors.forename: Sheng-yun
authors.initials: SY
authors.lastname: Lin
authors.forename: Chu-yun
authors.initials: CY
authors.lastname: Shen
authors.forename: Jian-ping
authors.initials: JP
authors.lastname: Jiang
authors.forename: Li-qiang
authors.initials: LQ
authors.lastname: Wu
authors.forename: Tie-ying
authors.initials: TY
authors.lastname: Dai
authors.forename: Wen-bing
authors.initials: WB
authors.lastname: Qian
authors.forename: Hai-tao
authors.initials: HT
authors.lastname: Meng
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D032064:Hedyotis / Q000737:chemistry*; D006801:Humans; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology*; D016328:NF-kappa B / Q000378:metabolism; D011134:Polysaccharides / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism
chemical_list: D016328:NF-kappa B; D011134:Polysaccharides; D051057:Proto-Oncogene Proteins c-akt; C505407:CASP3 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9