Promastigote Form Of Parasite Research Articles

Evaluation of leishmanicidal effect of Euphorbia petiolata extract by in vivo anti-leishmanial assay using promastigotes of Leishmania major

The extract of different species of Euphorbia has been successfully used as a remedy for treatment of cutaneous leishmaniasis. The aim of this study was to assess the in vitro leishmanicidal effect of Euphorbia petiolata (E. petiolata) extract. Ethanolic percolated and methanolic Soxhlet extract of E. petiolata on promastigotes of L. major at different concentrations of extracts, one positive control group and one negative control group as well as 1 solvent control were prepared and placed in 24-well plates that contained 40,000 parasites/well. Afterwards, plates were incubated at 25 ˚C for six days and number of parasites in each well were determined on days 2, 4 and 6 of the experiment. Both percolated and Soxhlet extracts in methanol and DMSO solvents had significant effects (equal to that of amphotericin B) on promastigote form of parasite at the concentration of 1 mg/ml. At lower concentrations, the extracts of E. petiolata had favorable leishmanicidal activity and killed L. major promastigotes dose-dependently. Our results support the possibility of E. petiolata extracts application as an anti-leishmanial agent with similar effects to amphotericin B.

Evidence for the existence of a surface receptor for ferriclactoferrin and ferrictransferrin associated with the plasma membrane of the protozoan parasite Leishmania donovani.

Previous work has demonstrated the ability of the promastigote form of the protozoan parasite Leishmania chagasi to utilize iron chelated to lactoferrin and transferrin for growth and metabolism. We have obtained evidence suggesting that the promastigote form of the parasite possesses specific binding sites for lactoferrin and transferrin. Lactoferrin binding appears to be: 1) independent of whether or not the protein contains iron; 2) not inhibited by transferrin; and 3) independent of whether the organism is in log or stationary phase of growth. Transferrin binding is: 1) markedly greater if the protein is iron loaded; 2) inhibited by the presence of lactoferrin; and 3) independent of whether the organism is in log or stationary growth phase. Preliminary ligand blot analyses are consistent with the presence of a protein or proteins which bind lactoferrin and/or transferrin. The relationship to these binding sites to those described in other protozoan species requires further investigation.