A rapid decrease in parasitaemia remains the major goal for new antimalarial drugs
and thus, in vivo models must provide precise results concerning parasitaemia
modulation. Hydroxyethylamine comprise an important group of alkanolamine compounds
that exhibit pharmacological properties as proteases inhibitors that has already been
proposed as a new class of antimalarial drugs. Herein, it was tested the antimalarial
property of new nine different hydroxyethylamine derivatives using the green
fluorescent protein (GFP)-expressing Plasmodium berghei strain. By
comparing flow cytometry and microscopic analysis to evaluate parasitaemia
recrudescence, it was observed that flow cytometry was a more sensitive methodology.
The nine hydroxyethylamine derivatives were obtained by inserting one of the
following radical in the para position: H, 4Cl, 4-Br, 4-F, 4-CH3,
4-OCH3, 4-NO2, 4-NH2 and 3-Br. The antimalarial test showed that the compound that
received the methyl group (4-CH3) inhibited 70% of parasite growth. Our results
suggest that GFP-transfected P. berghei is a useful tool to study the recrudescence
of novel antimalarial drugs through parasitaemia examination by flow cytometry.
Furthermore, it was demonstrated that the insertion of a methyl group at the
para position of the sulfonamide ring appears to be critical for
the antimalarial activity of this class of compounds.