Effect of artmether, hemin and Fe3+ on recombinant lactate dehydrogenase from Schistosoma japonicum

ObjectiveTo explore antischitosome effects of artemether, hemin and Fe3+ on Sj LDH.MethodsEnzyme activity of rSj LDH was assayed in the standard reaction system by adding different concentration of reagents (0.00-0.10 mM artemether, 0.00-0.02 mM hemin, 0.00-0.50 mM Fe3+). Same solvents of the each reagent were used as control.ResultsThere was no enzyme activity inhibition observed at 0.10 mM artemther; obivious inhibition for lactate oxidation reaction and pyruvate reduction reaction were detected at 0.002 mM and 0.004 mM of hemin, respectively; comparing with that of the control (P<0.05). The relative enzymatic activity inhibitions for pyruvate reduction reaction and lactate oxidation reaction at 0.02 mM hemin were 93.48% and 100.00%, respectively, comparing with that of the control (P<0.01); both pyruvate reduction and lactate oxidation reaction were inhibited completely at 0.50 mM Fe3+, comparing with that of the control (P<0.01).ConclusionsThe results implied that Sj LDH was not the direct molecular target of artemether. Hemin and Fe3+ are inhibitors of Sj LDH.