title: [Comparative study of cytotoxicity induced by two kinds of bentonite particles in vitro].
abstract: OBJECTIVE
  To study comparatively the cytotoxicity induced by acid bentonite and organic bentonite.
  
  
  METHODS
  The cytotoxicity of two kinds of bentonite was detected using CCK8 assay, neutral red uptake (NRU) assay, lactate dehydrogenase (LDH) leakage assay, apoptosis assay and hemolysis assay. In hemolysis assay human erythrocytes served as target cells and were exposed to the two kinds of bentonite at the doses of 0, 0.3125, 0.6250, 1.2500 and 2.5000 mg/ml for ten min. In other four assays, human B lymphoblast cells (HMy2.CIR) served as target cells and were exposed to the two kinds of bentonite at the doses of 0, 10, 20, 30, 60, 120 and 180 microg/ml for four h.
  
  
  RESULTS
  In hemolysis assay, the hemolysis rates induced by two kinds of bentonite at all doses were significantly higher than that of control (P<0.05); in CCK-8 assay, the cellular activities in acid bentonite group at the doses > or =30 microg/ml and in organic bentonite group at the doses > or =20 microg/ml were significantly lower than that of control (P<0.01); the similar results appeared in NRU assay and LDH assay, and the dose-effect relationship was observed in above 4 assays. In apoptosis assay, the early apoptosis cell rates in acid bentonite group at the dose of 180 microg/ml and in organic bentonite group at the doses of 120,180 microg/ml were significantly higher than that of control (P<0.05). Moreover, the results of five in vitro assays indicated the cytotoxicity induced by organic bentonite was higher than that induced by acid bentonite.
  
  
  CONCLUSIONS
  Two kinds of bentonite could induce cytotoxicity, such as apoptosis and damage of cell membrane. The cytotoxicity of organic bentonite is higher than that of acid bentonite due to the different industrial treatment and characteristics of two kinds of bentonite particles.
authors.affiliation: Institute of Environmental Medicine, Medical School, Zhejiang University, Hangzhou, Zhejiang Province 310058, China.
authors.forename: Ye-Zhen
authors.initials: YZ
authors.lastname: Lu
authors.forename: Mei-Bian
authors.initials: MB
authors.lastname: Zhang
authors.forename: Xiao-Xue
authors.initials: XX
authors.lastname: Li
authors.forename: Song-Xue
authors.initials: SX
authors.lastname: Yan
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
authors.forename: Ming-Luan
authors.initials: ML
authors.lastname: Xing
authors.forename: Hua
authors.initials: H
authors.lastname: Zou
authors.forename: Ji-Liang
authors.initials: JL
authors.lastname: He
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001546:Bentonite / Q000633:toxicity*; D002460:Cell Line; D003601:Cytotoxicity Tests, Immunologic; D004912:Erythrocytes / Q000187:drug effects / Q000473:pathology; D006461:Hemolysis / Q000187:drug effects*; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000473:pathology
chemical_list: D001546:Bentonite