title: [Assessment of Antimalarial Activity of Choline Derivatives against Plasmodium falciparum Growth in vitro by SYBR Green I Method].
abstract: OBJECTIVE
  To investigate the antimalarial activity of four choline derivatives against Plasmodium falciparum 3D7 strain growth in vitro.
  
  
  METHODS
  Four choline derivatives MD [N-dodecyl-N-(2-hydroxyethyl)-N,N- dimethyl ammonium bromide], ED [N-dodecyl-N-(2-hydroxyethyl)-N,N-diethyl ammonium bromide], MT [N-tetradecyl-N- (2-hydroxyethyl)-N,N-dimethyl ammonium bromide], and ET [N-tetradecyl-N-(2-hydroxyethyl)-N,N-diethyl ammonium bromide] were dissolved separately in DMSO at serial concentrations (1-10(5) µmol/L). The solutions were diluted by 1,000-fold with RPMI 1640 medium. 20 µl drug-containing medium and 80 µl P. falciparum-infected erythrocyte suspension (2% final hematocrit and 0.3%-0.5% parasitemia) were added to each well of microtiter plates. Drug effect on the in vitro growth of P. falciparum was measured by SYBR Green I method. The half maximal inhibitory concentration (IC50) was calculated from dose-response curves. Artemisinine served as positive control.
  
  
  RESULTS
  Artemisinine, MD, ED, MT, and ET showed different degrees of dose-dependent inhibition on P. falciparum growth. When the MD concentration was above 10 nmol/L, the inhibition rate increased significantly. Both ED and ET showed significant inhibitory effects at high concentrations, with inhibition rate of > 95% when their doses were > 10(4) nmol/L. The IC50 values of MD, ED, MT, and ET were 1 620, 33.9, 116, and 68.9 nmol/L, respectively, all significantly higher than that of artemisinine (5.7 nmol/L) (P < 0.05).
  
  
  CONCLUSIONS
  The four choline derivatives show certain antimalarial activity, which is lower than that of artemisinine. Among the four derivatives, ED has the strongest antimalarial activity against P. falciparum 3D7 strain.
authors.forename: Hui-fang
authors.initials: HF
authors.lastname: Cheng
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.forename: Juan
authors.initials: J
authors.lastname: Gao
authors.forename: Rui-li
authors.initials: RL
authors.lastname: Wang
authors.forename: Shu-qiu
authors.initials: SQ
authors.lastname: Zhang
mesh_terms: D000962:Antimalarials; D037621:Artemisinins; D052160:Benzothiazoles; D002794:Choline; D003959:Diamines; D006801:Humans; D016778:Malaria, Falciparum; D009930:Organic Chemicals; D010963:Plasmodium falciparum; D011804:Quinolines
chemical_list: D000962:Antimalarials; D037621:Artemisinins; D052160:Benzothiazoles; D003959:Diamines; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I; C031327:artemisinin; D002794:Choline