Curcumin is the major phenolic compound found in turmeric, a dry
powder of rhizomes and roots of the plant, Curcuma longa L., which is widely used as spice and food colorant around the world, and in herbal medicinal practice in Asian countries. The present study reports the leishmanicidal activity of trans-
dibenzalacetone (DBA), a synthetic monoketone analog of
curcumin, against Leishmania donovani parasites. We for the first time report the antiproliferative effect of a
curcumin analog (DBA) on the intracellular amastigotes of L. donovani, the clinically more relevant stage of the parasite than its promastigotes stage. The leishmanicidal effect of DBA was further confirmed by scanning and transmission electron microscopies. Cell growth was arrested in G0/G1 phase with increased concentration of cytosolic
calcium and dissipation of mitochondrial membrane potential. Further, the unique
trypanothione/
trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by DBA. This economically synthesizable simple monoketone analog of
curcumin has the potential for field use against
visceral leishmaniasis which is currently widespread in tropical and subtropical developing countries of the world. In conclusion, we have identified an analog of
curcumin for potential applications against
leishmaniasis, based on its strong
antiparasitic activity and low toxicity. This
curcumin analog compares favorably, at least in vitro, with the existing medication
miltefosine.