Figure 1.
Chemical structures of edelfosine, miltefosine, perifosine and erucylphosphocholine.
Figure 2.
In vitro effects of APLs on the viability of S. mansoni adult worms measured by MTT assay.
Couples of adult worms were treated with edelfosine (EDLF), miltefosine (MILTE), perifosine (PERI) or erucylphosphocholine (ErPC) at the indicated concentrations for 168 h. Data are means ± SEM of three separate experiments. Asterisks represent statistical significance with respect to control-live group. (*) P<0.05; (***) P<0.001.
Table 1.
In vitro effects of APLs on 56-day-old S. mansoni worms upon 168 h of culture.
Figure 3.
In vitro effects of edelfosine (EDLF) on the viability of S. mansoni adult worms measured by MTT assay.
Couples of adult worms were treated with EDLF at the indicated concentrations for 24 h, 48 h and 74 h. Data are means ± SEM of three separate experiments. Asterisks represent statistical significance with respect to control-live group. (**) P<0.01; (***) P<0.001.
Figure 4.
In vitro effects of edelfosine (EDLF) on the viability of S. mansoni adult worms measured by propidium iodide (PI) permeabilization and in vitro effects of edelfosine on egg production.
Couples of adult worms were treated with EDLF at the indicated concentrations for 24 h (A) or 168 h (B), and then analyzed for membrane permeabilization using PI staining (A) and for the number of laid eggs, monitored using an inverted microscope (B). RFU, relative fluorescence units. Data are means ± SEM of three separate experiments. Asterisks represent statistical significance with respect to control-live group. (**) P<0.01; (***) P<0.001.
Figure 5.
Distribution of the fluorescent edelfosine analog in S. mansoni adult female worms.
A) Control of autofluorescence in a female cultured in RPMI-1640 only. B) Female incubated with the fluorescent edelfosine analog. Arrows show a slightly increased staining at the tegument. Scale bar, 0.2 mm.
Figure 6.
Edelfosine-induced apoptosis-like death as assessed by TUNEL assay.
Adult worms were untreated (Control) or treated with 20 µM edelfosine (EDLF) for 12 h, 48 h and 72 h. Worms were analyzed by fluorescence microscopy for propidium iodide (PI) staining and TUNEL assay, as well as for DAPI staining (nuclei) and light microscopy morphology. Merging of PI and TUNEL panels (Merge) shows the apoptotic nuclei in yellow. Data shown are representative of four independent experiments. Histograms indicate the percentage of TUNEL-positive cells, as an estimate of cells undergoing apoptosis. For each experiment, at least 100 cells were analyzed. Data are means ± SEM of three separate experiments. Asterisks represent statistical significance with respect to control-live group. (***) P<0.001. Scale bar, 100 µm.
Figure 7.
Morphological changes in S. mansoni adult worms following praziquantel or edelfosine treatments.
H&E stained sections of freshly recovered male parasites that were untreated (Control) or treated with 10 µM praziquantel (PZQ) or 20 µM edelfosine (EDLF) for 2 days. Tubercle collapse (arrow), damages of the tegument surface, vacuolization of the subtegumental cells (asterisk) and destruction of muscle layers (arrowhead) were observed after treatment with PZQ or EDLF.
Figure 8.
Effect on adult worm and egg burdens after treatment of S. mansoni-infected mice with praziquantel (PZQ) or edelfosine (EDLF).
(A) male and female worm burdens. (B) egg burden in liver. Infected mice were treated with 500 mg/kg (x2) PZQ or 45 mg/kg (x10) EDLF. Each point represents data from an individual mouse. Horizontal bars indicate average values. (*) P<0.05. (**) P<0.01.